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11 pages, 715 KiB  
Article
Effect of Neutrophil–Platelet Interactions on Cytokine-Modulated Expression of Neutrophil CD11b/CD18 (Mac-1) Integrin Complex and CCR5 Chemokine Receptor in Stable Coronary Artery Disease: A Sub-Study of SMARTool H2020 European Project
by Silverio Sbrana, Stefano Salvadori, Rosetta Ragusa, Elisa Ceccherini, Adrian Florentin Suman, Antonella Cecchettini, Chiara Caselli, Danilo Neglia, Gualtiero Pelosi and Silvia Rocchiccioli
Hearts 2024, 5(3), 410-420; https://doi.org/10.3390/hearts5030029 (registering DOI) - 16 Sep 2024
Viewed by 92
Abstract
Atherosclerosis is an inflammatory disease wherein neutrophils play a key role in plaque evolution. We observed that neutrophil CD11b was associated with a higher necrotic core volume in coronary plaques. Since platelets modulate neutrophil function, we explored the influence of neutrophil–platelet conjugates on [...] Read more.
Atherosclerosis is an inflammatory disease wherein neutrophils play a key role in plaque evolution. We observed that neutrophil CD11b was associated with a higher necrotic core volume in coronary plaques. Since platelets modulate neutrophil function, we explored the influence of neutrophil–platelet conjugates on the cytokine-modulated neutrophil complex CD11b/CD18 and CCR5 receptor expression. In 55 patients [68.53 ± 7.95 years old (mean ± SD); 71% male], neutrophil positivity for CD11b, CD18 and CCR5 was expressed as Relative Fluorescence Intensity (RFI) and taken as a dependent variable. Cytokines and chemokines were assessed by ELISA. Following log-10-based logarithmic transformation, they were used as independent variables in Model 1 of multiple regression together with Body Mass Index and albumin. Model 1 was expanded with the RFI of neutrophil CD41a+ (model 2). The RFI of neutrophil CD41a+ correlated positively and significantly with CD11b, CD18, and CCR5. In Model 2, CCR5 correlated positively only with the RFI of neutrophil CD41a+. Albumin maintained its positive effect on CD11b in both models. These observations indicate the complexity of neutrophil phenotypic modulation in stable CAD. Despite limitations, these findings suggest there is a role played by neutrophil–platelet interaction on the neutrophil cytokine-modulated expression of adhesive and chemotactic receptors. Full article
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<p>Representative example of flow cytometry quantification of complexes neutrophil-CD41a+ (NPAs, neutrophil–platelet aggregates). (<b>A</b>) Neutrophil cluster identification (region R1) based on its low CD14 expression (FL3) and side-scattering (SSC) morphological characteristics. (<b>B</b>) The R1-based histogram’s subtraction analysis [positive events (continuous line) minus isotype control (dotted line)] was used to quantify both the percentage of complexes CD41a+ (percentage of events in M1 marker) and their RFI (median of M1 gray histogram minus median of the isotype control).</p>
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<p>Schematic representation of the main soluble effector molecules involved in the platelet-mediated modulation model of circulating neutrophil phenotypes proposed in our study.</p>
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14 pages, 4894 KiB  
Article
Preparation of Polyclonal Antibodies to Barley Granule-Bound Amylopectin Synthase Ia and Their Application in the Characterization of Interacting Proteins
by Qiyan Zhou, Boai Xi, Noman Shoaib, Yan Gao, Zhenbin Cheng, Rizwan Ali Kumbhar, Zongyun Feng, Yajie Liu, Hui Zhao and Guowu Yu
Agronomy 2024, 14(9), 2058; https://doi.org/10.3390/agronomy14092058 - 9 Sep 2024
Viewed by 315
Abstract
The production of amylose is facilitated by granule-bound starch synthase (GBSS). Despite its importance, the specific protein interactions involving barley grain-bound starch synthase Ia (HvGBSSIa) remain poorly understood. To elucidate this, we engineered a pET-32a-HvGBSSIa prokaryotic expression vector for specific expression in E. [...] Read more.
The production of amylose is facilitated by granule-bound starch synthase (GBSS). Despite its importance, the specific protein interactions involving barley grain-bound starch synthase Ia (HvGBSSIa) remain poorly understood. To elucidate this, we engineered a pET-32a-HvGBSSIa prokaryotic expression vector for specific expression in E. coli Rosetta cells. A rabbit anti-HvGBSSIa polyclonal antibody was generated and employed to enrich HvGBSSIa-binding proteins from barley grains through immunoprecipitation. The isolated complexes were then resolved through SDS-PAGE, and the constituent proteins were identified using mass spectrometry coupled with database searches. Our results confirmed the successful preparation of a highly specific polyclonal antibody against HvGBSSI. Furthermore, differential expression of HvGBSSIa was assessed across various barley tissues and developmental stages of the grain, revealing peak expression at 25 days post-flowering. Proteins interacting with HvGBSSIa, including sucrose synthase and starch branching enzyme, were identified through co-immunoprecipitation. This study lays the groundwork for further detailed analyses of the HvGBSSIa protein complex in barley. Full article
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<p>Prediction of signal peptide, hydrophobicity, transmembrane structural domains, phosphorylation sites, and functional structural domains of HvGBSSIa protein. (<b>A</b>) Prediction of signal peptide of HvGBSSIa protein (neural network approach). S, C, and Y scores are represented by three curves, which comprehensively indicate the presence or absence of signal peptide and cleavage site of the protein; (<b>B</b>) affinity water analysis of HvGBSSIa protein; (<b>C</b>) transmembrane region of HvGBSSIa protein. The purple line represents the transmembrane region; (<b>D</b>) prediction of phosphorylation sites of HvGBSSIa protein; (<b>E</b>) functional domain prediction of HvGBSSIa protein.</p>
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<p>Comparison of major crops with HvGBSSIa sequences. (<b>A</b>) Comparison of predicted HvGBSSIa amino acid sequences with GBSSI homologs (HvGBSSIa: 1aa-589aa), red boxes are identical amino acids; (<b>B</b>) phylogenetic analysis of HvGBSSIa in major crops; (<b>C</b>) sequence structure analysis. Exons are indicated by bold yellow boxes, and introns are indicated by black lines; (<b>D</b>) conserved motif analysis of HvGBSSIa protein; (<b>E</b>) amino acid sequences of 10 motifs are conserved, and the amino acid letters highly reflect the degree of conserved sites. Symbols include Ta, <span class="html-italic">Triticum aestivum</span> (accession id: XP_044437438.1); Zm, <span class="html-italic">Zea mays</span> (accession id: NP_001358937.1); Os, <span class="html-italic">Oryza sativa</span> (accession id: NP_001389652.1); At, <span class="html-italic">Arabidopsis thaliana</span> (accession id: NP_001358937).</p>
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<p>Expression and purification of <span class="html-italic">HvGBSSIa</span>. (<b>A</b>) Total RNA from barley leaves was extracted and analyzed via agarose gel electrophoresis, revealing 28S and 18S rRNA bands; (<b>B</b>) the cDNA was synthesized from the extracted RNA, confirming successful reverse transcription; (<b>C</b>) the <span class="html-italic">HvGBSSIa</span> gene was amplified using specific primers, yielding an 1827 bp product; (<b>D</b>) cloning of <span class="html-italic">HvGBSSIa</span> into the pET-32a(+) vector was confirmed using restriction digestion, resulting in an 1827 bp fragment; (<b>E</b>) schematic representation of the recombinant pET-32a-HvGBSSIa plasmid; (<b>F</b>) SDS-PAGE analysis of <span class="html-italic">E. coli</span> Rosetta (DE3) cells expressing the recombinant protein, collected at different time points post-IPTG induction (0, 2, 4, 6 h), showing increased expression of the protein over time (indicated by the arrow); (<b>G</b>) purification of HvGBSSIa (indicated by the arrow) using affinity chromatography, with fractions labeled as FT (flow-through), W1–W3 (wash fractions), and E1–E5 (elution fractions), confirming the successful purification of the protein.</p>
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<p>HvGBSSIa rabbit antiserum specificity assay and validation of HvGBSSIa antibody in barley tissues. (<b>A</b>) SDS-PAGE to determine the concentration of HIS-HvGBSSIa antigen; (<b>B</b>) antigen gradient dilution western blotting assay to detect the specificity of prokaryotic expression of HvGBSSIa protein (antibody dilution ratio of 1:400); (<b>C</b>) antibody with different dilution ratios western blotting assay to detect the specificity of 1 μg of HvGBSSIa protein specificity of prokaryotic expression; (<b>D</b>) SDS-PAGE electropherograms of total protein of “Tongxi” barley kernels at different times after pollination; (<b>E</b>) western blotting assay to detect the specificity of HvGBSSIa protein in barley; (<b>F</b>) image J software to analyze the relative expression of HvGBSSIa in different tissues of barley and at different developmental periods of the kernel at the protein levels; (<b>G</b>) analysis of HvGBSSIa transcript expression levels in different tissues of barley and after different days of pollination. Total protein 30 µg. The dilution ratio of the HvGBSSIa antibody is 1:500. lane M: protein marker (10–180 kDa). In all cases, the error bars show SD. Data are shown as the mean ± SE (<span class="html-italic">n</span> = 3), one-way ANOVA **** show <span class="html-italic">p</span>-value &lt;0.0001.</p>
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<p>SDS-PAGE analysis of immunoprecipitation eluates. (<b>A</b>) SDS-PAGE of HvGBSSIa anti-body immunoprecipitation; input is 5% of total protein. (<b>B</b>) Western blot detection of HvGBSSIa antibody immunoprecipitation from 25 DAP barley seeds; (<b>C</b>) mass spectrometry matching to the number of peptides of HvGBSSIa (b: An ionic fragment formed from the process of breaking the N-terminal bond of a peptide chain; y: An ionic fragment formed from the process of breaking the C-terminal bond of a peptide chain). Black arrows indicate HvGBSSIa protein target bands, lane M: protein labeling (10–180 kDa).</p>
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21 pages, 1549 KiB  
Review
AI-Driven Deep Learning Techniques in Protein Structure Prediction
by Lingtao Chen, Qiaomu Li, Kazi Fahim Ahmad Nasif, Ying Xie, Bobin Deng, Shuteng Niu, Seyedamin Pouriyeh, Zhiyu Dai, Jiawei Chen and Chloe Yixin Xie
Int. J. Mol. Sci. 2024, 25(15), 8426; https://doi.org/10.3390/ijms25158426 - 1 Aug 2024
Viewed by 1430
Abstract
Protein structure prediction is important for understanding their function and behavior. This review study presents a comprehensive review of the computational models used in predicting protein structure. It covers the progression from established protein modeling to state-of-the-art artificial intelligence (AI) frameworks. The paper [...] Read more.
Protein structure prediction is important for understanding their function and behavior. This review study presents a comprehensive review of the computational models used in predicting protein structure. It covers the progression from established protein modeling to state-of-the-art artificial intelligence (AI) frameworks. The paper will start with a brief introduction to protein structures, protein modeling, and AI. The section on established protein modeling will discuss homology modeling, ab initio modeling, and threading. The next section is deep learning-based models. It introduces some state-of-the-art AI models, such as AlphaFold (AlphaFold, AlphaFold2, AlphaFold3), RoseTTAFold, ProteinBERT, etc. This section also discusses how AI techniques have been integrated into established frameworks like Swiss-Model, Rosetta, and I-TASSER. The model performance is compared using the rankings of CASP14 (Critical Assessment of Structure Prediction) and CASP15. CASP16 is ongoing, and its results are not included in this review. Continuous Automated Model EvaluatiOn (CAMEO) complements the biennial CASP experiment. Template modeling score (TM-score), global distance test total score (GDT_TS), and Local Distance Difference Test (lDDT) score are discussed too. This paper then acknowledges the ongoing difficulties in predicting protein structure and emphasizes the necessity of additional searches like dynamic protein behavior, conformational changes, and protein–protein interactions. In the application section, this paper introduces some applications in various fields like drug design, industry, education, and novel protein development. In summary, this paper provides a comprehensive overview of the latest advancements in established protein modeling and deep learning-based models for protein structure predictions. It emphasizes the significant advancements achieved by AI and identifies potential areas for further investigation. Full article
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<p>The flowchart of this review paper. It shows the overall flow of this paper, including the sequence of sections and their interconnections.</p>
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<p>Sample FASTA file for protein (PDB ID 7SF8 [<a href="#B78-ijms-25-08426" class="html-bibr">78</a>]) with 4 chains.</p>
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<p>Four levels of protein structures. (<b>A</b>) The primary structure is shown as 3-letter codes, unlike <a href="#ijms-25-08426-f002" class="html-fig">Figure 2</a>. The sequence is randomly written as a demonstration. (<b>B</b>–<b>D</b>) The secondary structure shows alpha helices as an example. Secondary, tertiary, and quaternary structures are visualized in PyMOL [<a href="#B80-ijms-25-08426" class="html-bibr">80</a>], a visualization tool for molecules, and macromolecules like proteins. The PDB ID used is 7SF8 [<a href="#B78-ijms-25-08426" class="html-bibr">78</a>].</p>
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<p>Comparison of experimental structure of protein (PDB ID 7SF8 [<a href="#B78-ijms-25-08426" class="html-bibr">78</a>]) and predicted structure by AlphaFold2. (<b>A</b>) PDB file of 7SF8 [<a href="#B78-ijms-25-08426" class="html-bibr">78</a>] shown in PyMOL [<a href="#B80-ijms-25-08426" class="html-bibr">80</a>]. (<b>B</b>) Predicted structure by AlphaFold2 with confidence scores using protein sequence (PDB ID 7SF8 [<a href="#B78-ijms-25-08426" class="html-bibr">78</a>]). A higher score means the model is more confident in the correctness of the predictions. (<b>C</b>) Figures (<b>A</b>) and (<b>B</b>) are shown together in PyMOL [<a href="#B80-ijms-25-08426" class="html-bibr">80</a>]. Purple is the AlphaFold2 prediction. (<b>D</b>–<b>F</b>) The zoomed-in area where AlphaFold2 has low confidence scores. There are some significant differences in these areas.</p>
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7 pages, 628 KiB  
Brief Report
Effectiveness of Combination of Tibolone and Lactobacilli Plus Lactoferrin in Postmenopausal Women with Vulvar Vestibular Pain: A Preliminary Report
by Vincenzo De Leo, Laura Governini, Rosetta Ponchia, Dario Recalcati and Filippo Murina
Nutrients 2024, 16(14), 2378; https://doi.org/10.3390/nu16142378 - 22 Jul 2024
Viewed by 956
Abstract
Background: Postmenopausal dyspareunia and vulvar pain are common complaints, affecting about 60% of women within a few years after hormone levels begin to decline (such as estrogen and androgen). Atrophic changes mainly located in the vulvar vestibule and vulnerability to vulvovaginal infections in [...] Read more.
Background: Postmenopausal dyspareunia and vulvar pain are common complaints, affecting about 60% of women within a few years after hormone levels begin to decline (such as estrogen and androgen). Atrophic changes mainly located in the vulvar vestibule and vulnerability to vulvovaginal infections in postmenopause could be predisposing factors to the development of vulvar burning/pain and introital dyspareunia (vestibulodynia secondary to atrophy). Tibolone is the most effective and safe alternative for treating menopausal symptoms. The role of Lactobacilli and lactoferrin shows its effectiveness in the treatment of vaginal microbiota dysbiosis. The aim of the present study was to assess the efficacy of the combination of tibolone and an oral-specific Lactobacilli mixture in combination with bovine lactoferrin as synergistic therapy for the treatment of vestibulodynia related to atrophy. Methods: In this study, we included 35 postmenopausal women with at least 1 year of amenorrhea, affected by vulvar burning/pain and introital dyspareunia. All participants received treatment with open-label, oral Tibolone 2.5 mg and Lactobacilli mixture (5 × 109 CFU per capsule) in combination with bovine lactoferrin (Respecta®). Each product was taken once daily for 90 days. Results: After 90 d of therapy with TIB+ Respecta®, in 30 women that completed the treatment, there was a statistically significant decrease from the baseline in the mean of the Visual Analog Scale for vulvar burning/pain and a reduction in scores in the pain evaluation test. Conclusions: This study provides evidence that the combination of TIB+ Respecta® was effective in reducing symptoms related to vestibular pain and hypersensitivity in a postmenopausal setting. Full article
(This article belongs to the Section Prebiotics and Probiotics)
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<p>Visual Analog Scale (VAS). (<b>A</b>) Histograms show the mean values ± SD at T0 (light gray) and T1 (dark gray), after 90 d of treatment. *** <span class="html-italic">p</span> &lt; 0.01. (<b>B</b>) Stacked line chart shows a comparison of pre- and post-treatment individual scores of the intervention patient group.</p>
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<p>Cotton swab test—vaginal vestibular tissue sensitivity evaluation. (<b>A</b>) Histograms show the mean values ± SD at T0 (light gray) and T1 (dark gray), after 90 d of treatment. *** <span class="html-italic">p</span> &lt; 0.01. (<b>B</b>) Stacked line chart shows comparison of pre- and post-treatment individual scores of the intervention patient group.</p>
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13 pages, 275 KiB  
Article
The Impact of Three White-Rot Fungi on Nutrient Availability, Greenhouse Gas Emissions, and Volatile Fatty Acid Production in Myceliated Sorghum
by Lydia K. Olagunju, Omoanghe S. Isikhuemhen, Peter A. Dele, Felicia N. Anike, Joel O. Alabi, Kelechi A. Ike, Yasmine Shaw, Rosetta M. Brice, Oluteru E. Orimaye, Michael Wuaku, Nkese S. Udombang and Uchenna Y. Anele
Foods 2024, 13(14), 2199; https://doi.org/10.3390/foods13142199 - 12 Jul 2024
Viewed by 744
Abstract
Our study employed Pleurotus ostreatus, P. djamor, and Trametes versicolor (white rot fungi = WRF) in the process of solid-state fermentation (SSF) to convert sorghum grains into myceliated sorghum (MS). The MS was then used for in vitro studies to assess [...] Read more.
Our study employed Pleurotus ostreatus, P. djamor, and Trametes versicolor (white rot fungi = WRF) in the process of solid-state fermentation (SSF) to convert sorghum grains into myceliated sorghum (MS). The MS was then used for in vitro studies to assess changes in nutrient content compared to untreated sorghum (control). The results demonstrated a significant (p < 0.001) increase in dry matter (DM), crude protein (CP), ash, neutral detergent fiber (NDF), and acid detergent fiber (ADF) contents of MS. Specifically, CP and ash values saw a remarkable increase from 68 to 330% and 40 to 190% in MS, respectively. Additionally, NDF and ADF degradability values increased significantly (p < 0.001) by 81.5% and 56.2% in P. djamor-treated MS at 24 h post-incubation. The treatment × time interaction was also significant (p < 0.001) for greenhouse gas (GHG) emissions. T. versicolor MS exhibited the highest total volatile fatty acid (TVFA) and propionate production. The use of WRF in the SSF process led to a significant improvement in the nutritional value of sorghum. Despite the varying effects of different WRF on the nutritional parameters in MS, they show potential for enhancing the feed value of sorghum in animal feed. Full article
9 pages, 449 KiB  
Article
Influence of Safety Warnings on the Prescribing Attitude of JAK Inhibitors for Rheumatoid Arthritis in Italy
by Marino Paroli, Andrea Becciolini, Alberto Lo Gullo, Simone Parisi, Elena Bravi, Romina Andracco, Valeria Nucera, Francesca Ometto, Federica Lumetti, Antonella Farina, Patrizia Del Medico, Matteo Colina, Viviana Ravagnani, Palma Scolieri, Maddalena Larosa, Marta Priora, Elisa Visalli, Olga Addimanda, Rosetta Vitetta, Alessandro Volpe, Alessandra Bezzi, Francesco Girelli, Aldo Biagio Molica Colella, Rosalba Caccavale, Eleonora Di Donato, Giuditta Adorni, Daniele Santilli, Gianluca Lucchini, Eugenio Arrigoni, Ilaria Platè, Natalia Mansueto, Aurora Ianniello, Enrico Fusaro, Maria Chiara Ditto, Vincenzo Bruzzese, Dario Camellino, Gerolamo Bianchi, Francesca Serale, Rosario Foti, Giorgio Amato, Francesco De Lucia, Ylenia Dal Bosco, Roberta Foti, Massimo Reta, Alessia Fiorenza, Guido Rovera, Antonio Marchetta, Maria Cristina Focherini, Fabio Mascella, Simone Bernardi, Gilda Sandri, Dilia Giuggioli, Carlo Salvarani, Maria Ilenia De Andres, Veronica Franchina, Francesco Molica Colella, Giulio Ferrero, Bernd Raffeiner and Alarico Arianiadd Show full author list remove Hide full author list
J. Clin. Med. 2024, 13(13), 3929; https://doi.org/10.3390/jcm13133929 - 4 Jul 2024
Viewed by 1117
Abstract
Background/Objectives: The Janus kinase inhibitors (JAKi) tofacitinib (TOFA), baricitinib (BARI), upadacitinib (UPA), and filgotinib (FILGO) are effective drugs for the treatment of rheumatoid arthritis. However, the US Food and Drug Administration (FDA) raised concerns about the safety of TOFA after its approval. This [...] Read more.
Background/Objectives: The Janus kinase inhibitors (JAKi) tofacitinib (TOFA), baricitinib (BARI), upadacitinib (UPA), and filgotinib (FILGO) are effective drugs for the treatment of rheumatoid arthritis. However, the US Food and Drug Administration (FDA) raised concerns about the safety of TOFA after its approval. This prompted the European Medicines Agency (EMA) to issue two safety warnings for limiting TOFA use, then extended a third warning to all JAKi in patients at high risk of developing serious adverse effects (SAE). These include thrombosis, major adverse cardiac events (MACE), and cancer. The purpose of this work was to analyze how the first two safety warnings from the EMA affected the prescribing of JAKi by rheumatologists in Italy. Methods: All patients with rheumatoid arthritis who had been prescribed JAKi for the first time in a 36-month period from 1 July 2019, to 30 June 2022 were considered. Data were obtained from the medical records of 29 Italian tertiary referral rheumatology centers. Patients were divided into three groups of 4 months each, depending on whether the JAKi prescription had occurred before the EMA’s first safety alert (1 July–31 October 2019, Group 1), between the first and second alerts (1 November 2019–29 February 2020, Group 2), or between the second and third alerts (1 March 2021–30 June 2021, Group 3). The percentages and absolute changes in the patients prescribed the individual JAKi were analyzed. Differences among the three groups of patients regarding demographic and clinical characteristics were also assessed. Results: A total of 864 patients were prescribed a JAKi during the entire period considered. Of these, 343 were identified in Group 1, 233 in Group 2, and 288 in Group 3. An absolute reduction of 32% was observed in the number of patients prescribed a JAKi between Group 1 and Group 2 and 16% between Group 1 and Group 3. In contrast, there was a 19% increase in the prescription of a JAKi in patients between Group 2 and Group 3. In the first group, BARI was the most prescribed drug (227 prescriptions, 66.2% of the total), followed by TOFA (115, 33.5%) and UPA (1, 0.3%). In the second group, the most prescribed JAKi was BARI (147, 63.1%), followed by TOFA (65, 27.9%) and UPA (33, 11.5%). In the third group, BARI was still the most prescribed JAKi (104 prescriptions, 36.1%), followed by UPA (89, 30.9%), FILGO (89, 21.5%), and TOFA (33, 11.5%). The number of patients prescribed TOFA decreased significantly between Group 1 and Group 2 and between Group 2 and Group 3 (p ˂ 0.01). The number of patients who were prescribed BARI decreased significantly between Group 1 and Group 2 and between Group 2 and Group 3 (p ˂ 0.01). In contrast, the number of patients prescribed UPA increased between Group 2 and Group 3 (p ˂ 0.01). Conclusions: These data suggest that the warnings issued for TOFA were followed by a reduction in total JAKi prescriptions. However, the more selective JAKi (UPA and FILGO) were perceived by prescribers as favorable in terms of the risk/benefit ratio, and their use gradually increased at the expense of the other molecules. Full article
(This article belongs to the Special Issue Rheumatoid Arthritis: Clinical Updates on Diagnosis and Treatment)
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<p>Variation over time in the number of patients prescribed a given JAKi.</p>
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12 pages, 787 KiB  
Article
Does Antrum Size Matter in Sleeve Gastrectomy? Volume II—A Retrospective Multicentric Study with Long-Term Follow-Up
by Claudio Gambardella, Simona Parisi, Salvatore Tolone, Francesco Saverio Lucido, Gianmattia del Genio, Luigi Brusciano, Rosetta Esposito, Domenico de Vito, Ludovico Docimo and Francesco Pizza
J. Clin. Med. 2024, 13(13), 3912; https://doi.org/10.3390/jcm13133912 - 3 Jul 2024
Viewed by 683
Abstract
Background: Laparoscopic sleeve gastrectomy (LSG) is the most widespread bariatric procedure due to its safety and efficacy. Despite continuous refinement, achieving a globally standardized procedure remains challenging. Moreover, due to its wide adoption, numerous studies have focused on complications associated with the technique, [...] Read more.
Background: Laparoscopic sleeve gastrectomy (LSG) is the most widespread bariatric procedure due to its safety and efficacy. Despite continuous refinement, achieving a globally standardized procedure remains challenging. Moreover, due to its wide adoption, numerous studies have focused on complications associated with the technique, such as gastroesophageal reflux disease (GERD). This study evaluates the impact of antrum size (wide antrectomy versus small antrectomy) in LSG on long-term anthropometric outcomes and complications in patients with morbid obesity. Methods: Body mass index (BMI), percentage of excess weight loss (%EWL) at a 5-year follow-up, GERD Health-Related Quality-of-Life (GERD-HRQL) scores, and obesity-related diseases of patients undergoing LSG with gastric resections starting 2 cm and 6 cm from the pylorus were retrospectively evaluated. Results: Between January 2015 and November 2019, 597 patients who met the criteria for LSG were included in the study. Group A (241 patients) underwent wide antrectomy, while Group B (356 patients) underwent small antrectomy. Weight, BMI, %EWL, and %TWL significantly improved at 6 and 12 months in the wide-antrectomy group. However, these differences diminished by 24 months, with no significant long-term differences in weight loss outcomes between the two groups at 5 years. Conversely, GERD-HRQL scores were significantly better in the small-antrectomy group until 24 months; thereafter, results were comparable between groups over the long term. Conclusions: Therefore, while wide antrectomy may offer superior short-term anthropometric outcomes, both techniques yield similar long-term results regarding weight management and GERD incidence. Larger prospective studies are needed to further address this issue. Full article
(This article belongs to the Special Issue Ulcers after Bariatric Surgery)
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<p>Study flowchart.</p>
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21 pages, 8245 KiB  
Review
Applications of Ground-Penetrating Radar in Asteroid and Comet Exploration
by Wei Guan, Yan Su, Jiawei Li, Shun Dai, Chunyu Ding and Yuhang Liu
Remote Sens. 2024, 16(12), 2188; https://doi.org/10.3390/rs16122188 - 17 Jun 2024
Cited by 1 | Viewed by 880
Abstract
Nowadays, asteroid and comet exploration is one of the most important components of deep space exploration. Through asteroid and comet exploration missions, it is possible to reveal the history of the formation and evolution of the solar system, to understand the origin and [...] Read more.
Nowadays, asteroid and comet exploration is one of the most important components of deep space exploration. Through asteroid and comet exploration missions, it is possible to reveal the history of the formation and evolution of the solar system, to understand the origin and evolution of the planets, and to improve scientific models and instruments. As a payload with the advantages of non-destructive, penetrating, and polarizing characteristics, ground-penetrating radar (GPR) has been widely used in lunar and Mars exploration, and will play an important role in planned asteroid and comet exploration missions. In this study, statistics on asteroid and comet exploration missions, scientific results, and space-based ground-penetrating radar (SB-GPR) utilization are presented for the three phases to date. According to the statistics, SB-GPR will play an important role in future Phase 2 and 3 missions. The focus of this study is on analyzing the mission flow, SB-GPR parameters, scientific objectives, and scientific results of the missions that have carried SB-GPR and those that are planned to carry SB-GPR, including the Hera, Rosetta, Castalia, and Tianwen-2 missions. On this basis, the development trends of asteroid and comet exploration missions, as well as the future development trends of SB-GPR design and signal interpretation, are discussed. Full article
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<p>(<b>a</b>) Pictures of 951 Gaspra and 243 Ida taken by Galileo (from NASA/JPL-Caltech); (<b>b</b>) 4179 Toutatis image taken by Chang’e 2 (from [<a href="#B21-remotesensing-16-02188" class="html-bibr">21</a>]); (<b>c</b>) schematic of the NEAR-Shoemaker spacecraft rendezvous with 433 Eros (from NASA); (<b>d</b>) the sample from asteroid Bennu (from NASA/Erika Blumenfeld and Joseph Aebersold).</p>
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<p>(<b>a</b>) Pictures of 951 Gaspra and 243 Ida taken by Galileo (from NASA/JPL-Caltech); (<b>b</b>) 4179 Toutatis image taken by Chang’e 2 (from [<a href="#B21-remotesensing-16-02188" class="html-bibr">21</a>]); (<b>c</b>) schematic of the NEAR-Shoemaker spacecraft rendezvous with 433 Eros (from NASA); (<b>d</b>) the sample from asteroid Bennu (from NASA/Erika Blumenfeld and Joseph Aebersold).</p>
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<p>(<b>a</b>) Schematic of the International Cometary Explorer spacecraft (from NASA); (<b>b</b>) images of Comet Halley’s nucleus were obtained by the Halley Multicolour Camera on board the Giotto spacecraft (from ESA/MPAe Lindau); (<b>c</b>) schematic of the Deep Impact spacecraft; (<b>d</b>) schematic diagram of the Rosetta mission deploying the Philae lander on comet 67P/Churyumov–Gerasimenko (from ESA/ATG medialab).</p>
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<p>The flow of the AIDA mission (from the ESA—Science Office). The NASA part is the DART mission, and the ESA part is the Hera mission.</p>
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<p>(<b>a</b>) Hera spacecraft; (<b>b</b>) Juventas CubeSat and four JuRa antennas (from [<a href="#B48-remotesensing-16-02188" class="html-bibr">48</a>]).</p>
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<p>The flow of the Rosetta mission (from ESA/ATG medialab): launched in March 2004; flew by asteroid 2867 Steins in May 2008; flew by asteroid 21 Lutetia in July 2010; arrived at comet 67P in August 2014; ended mission in September 2016.</p>
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<p>(<b>a</b>) The Rosetta orbiter; (<b>b</b>) the Philae lander (from ESA/ATG medialab).</p>
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<p>Propagation of signals from Philae on the nucleus to Rosetta in its orbit. The class of the signal is color-coded in green for strong SNR and good synchronization, yellow for acceptable SNR without synchronization, orange for low SNR, and red for absence of signal (from [<a href="#B55-remotesensing-16-02188" class="html-bibr">55</a>]).</p>
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<p>The flow of the Castalia mission: (1) launch; (2) Mars gravity assist; (3) optional cruise fly-bys; (4) target acquisition; (5) MBC phase; (6) tail excursion; (7) optional landing (EOM) (from [<a href="#B45-remotesensing-16-02188" class="html-bibr">45</a>]).</p>
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<p>SSR antennas and electronics box (from [<a href="#B45-remotesensing-16-02188" class="html-bibr">45</a>]).</p>
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<p>The flow of the Tianwen-2 mission (modified from [<a href="#B12-remotesensing-16-02188" class="html-bibr">12</a>]).</p>
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<p>Block diagram of ACSR (from [<a href="#B63-remotesensing-16-02188" class="html-bibr">63</a>]).</p>
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<p>(<b>a</b>) Low-surface-complexity asteroid model; (<b>b</b>) high-surface-complexity asteroid model.</p>
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<p>Radar observation mode.</p>
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<p>Echoes of low-surface-complexity asteroid models. (<b>a</b>) First-channel data-matched filter image; (<b>c</b>) all-channel data-matched filter image; (<b>e</b>) BP algorithm image; echoes of high-surface-complexity asteroid models; (<b>b</b>) 1st-channel data-matched filter image; (<b>d</b>) all-channel data-matched filter image; (<b>f</b>) BP algorithm image.</p>
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21 pages, 4164 KiB  
Systematic Review
Outcomes and Follow-Up Trends in Adrenal Leiomyosarcoma: A Comprehensive Literature Review and Case Report
by Federico Maria Mongardini, Maddalena Paolicelli, Antonio Catauro, Alessandra Conzo, Luigi Flagiello, Giusiana Nesta, Rosetta Esposito, Andrea Ronchi, Alessandro Romano, Renato Patrone, Ludovico Docimo and Giovanni Conzo
J. Clin. Med. 2024, 13(12), 3499; https://doi.org/10.3390/jcm13123499 - 14 Jun 2024
Viewed by 701
Abstract
Background: Leiomyosarcoma (LMS) originating from the adrenal gland is exceedingly rare, constituting a minute fraction of soft tissue sarcomas. Due to its rarity, with less than 50 documented cases in English medical literature, the diagnosis and management of adrenal LMS remain challenging. [...] Read more.
Background: Leiomyosarcoma (LMS) originating from the adrenal gland is exceedingly rare, constituting a minute fraction of soft tissue sarcomas. Due to its rarity, with less than 50 documented cases in English medical literature, the diagnosis and management of adrenal LMS remain challenging. The aim of this study was to perform a review of the literature, in order to evaluate the prognosis of these rare cancers and report our specific case. Methods: A systematic review of the literature was conducted using PubMed, Web of Science, Google Scholar, and Scopus databases, up to December 2020. The search utilized MeSH terms such as “Adrenal Gland Neoplasms,” “Leiomyosarcoma,” “Adrenalectomy,” and “Smooth Muscle Tumor.” The inclusion criteria focused on studies reporting patients with a histopathological diagnosis of adrenal leiomyosarcoma. The PRISMA guidelines were followed to ensure a comprehensive analysis. Results: Out of 63 identified studies, 43 met the inclusion criteria and were reviewed. These studies highlighted the rarity and aggressive behavior of adrenal leiomyosarcoma. Surgical excision remains the cornerstone of treatment, often complemented by adjuvant therapies. The reviewed case involved a 52-year-old woman who underwent a right laparoscopic adrenalectomy for a 9 × 7 × 6 cm grade 3 leiomyosarcoma. Despite subsequent adjuvant chemotherapy, hepatic metastases were detected, illustrating the aggressive nature of the disease. The literature underscores the importance of histopathological analysis and long-term surveillance for managing disease progression. Conclusions: Optimal management of adrenal leiomyosarcoma requires a multidisciplinary approach and meticulous follow-up. The rarity of the disease poses challenges for standardizing treatment, but surgical excision and tailored adjuvant therapies show promise. Further research is essential to refine treatment strategies and improve prognosis for this rare malignancy. Full article
(This article belongs to the Special Issue Current Management of Adrenal Tumors)
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<p>CT scan image: The right adrenal mass demonstrated adjacency to but no infiltration of the inferior vena cava, with venous drainage observed in the right ovarian vein. The yellow arrow indicates the 55 × 50 mm solid formation with a necrotic core and irregular peripheral enhancement in the right adrenal lodge.</p>
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<p>Intraoperative adrenal mass.</p>
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<p>Laparoscopic adrenalectomy, dissection from the residual adhesions.</p>
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<p>Histological findings. (<b>A</b>) Spindle cells neoplasms with expansive growth (Hematoxylin and eosin stain, original magnification 100×). (<b>B</b>) Coagulative necrosis (yellow arrow) (Hematoxylin and eosin stain, original magnification 100×). (<b>C</b>) Hyalinization of the stroma (red arrow) (Hematoxylin and eosin stain, original magnification 100×). (<b>D</b>) Neoplastic cells with nuclear atypia and mitotic figures (Hematoxylin and eosin stain, original magnification 200×). (<b>E</b>) Immunohistochemical positivity for smooth muscle actin (Immunohistochemical stain, original magnification 100×). (<b>F</b>) Immunohistochemical positivity for desmin (Immunohistochemical stain, original magnification 100×).</p>
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<p>Postoperative Abdominal CT: Non postoperative complications at the surgical site.</p>
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<p>PET-CT whole body: hepatic metastasis with a SUV of 14.3.</p>
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<p>Abdominal CT: hepatic metastasis identified with green arrows.</p>
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<p>PRISMA Statement: Flow-Chart. Diagram of the systematic review of the iterate performed in 4 databases from January 2000 up to December 2020. Search terms included: adrenal tumor, Leiomyosarcomas, mesenchymal tumor”. Inclusion criteria are shown in the central box. Major reasons for exclusion were duplicated papers from the different databases (n = 15), the language of the manuscripts included (n = 4). Further reasons for exclusion were primary location of the tumor in the Adrenal site (n = 1). This led to the final selection of 43 studies which fulfilled the inclusion criteria.</p>
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14 pages, 2381 KiB  
Article
Extending Polymer Opal Structural Color Properties into the Near-Infrared
by Giselle Rosetta, Matthew Gunn, John J. Tomes, Mike Butters and Chris E. Finlayson
Micro 2024, 4(2), 387-400; https://doi.org/10.3390/micro4020024 - 5 Jun 2024
Viewed by 790
Abstract
We report the fabrication and characterisation of near-IR reflecting films and coatings based on shear-assembled crystalline ensembles of polymer composite microspheres, also known as “polymer opals”. Extension of the emulsion polymerisation techniques for synthesis of tractable larger core-interlayer-shell (CIS) particles, of up to [...] Read more.
We report the fabrication and characterisation of near-IR reflecting films and coatings based on shear-assembled crystalline ensembles of polymer composite microspheres, also known as “polymer opals”. Extension of the emulsion polymerisation techniques for synthesis of tractable larger core-interlayer-shell (CIS) particles, of up to half a micron diameter, facilitates the engineering and processing of thin-film synthetic opals, with a tunable photonic stopband spanning an extended spectral range of λ ≈ 700–1600 nm. Samples exhibit strong “scattering cone” interactions, with considerable angular dependence and angle tuning possible, as measured with a goniometric technique. These intense optical resonances in the near-IR, particularly within the important region around λ ~ 800 nm, combined with an appreciable translucency within the visible light spectrum, is indicative of the potential applications in coatings technologies and solar cells. Full article
(This article belongs to the Special Issue Advances in Micro- and Nanomaterials: Synthesis and Applications)
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<p>(<b>a</b>) The core-interlayer-shell structure of polymer opal nanoparticles, with particle diameters scaling from around 330 to 510 nm in this study. (<b>b</b>) The Bending-Induced Oscillatory Shear (BIOS) pipeline, where the disordered base material is laminated between rigid PET sheets and shear is applied across heated rollers; the vector <math display="inline"><semantics> <mover accent="true"> <mi>p</mi> <mo stretchy="false">^</mo> </mover> </semantics></math> shows the film processing direction. The inset illustrates how errant particles are arranged into ordered structures by the melt-shearing technique. The photographic images, compare films before (left) and following (right) BIOS viewed under room lights; common scale bar (left) is 2 cm.</p>
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<p>(<b>a</b>) Scanning Electron Microscopy of the edge/slice of a 0-BIOS opal from Sample 2. (<b>b</b>) the surface of the 0-BIOS opal with the {111} direction out of the page, with random hcp, showing multiple distinct domains of order with auto-correlation function (inset). (<b>c</b>) a cleaved section of a 40 BIOS opal slice, and (<b>d</b>) the surface of the corresponding 40 BIOS opal from Sample 2, with auto-correlation analysis (inset). (<b>e</b>) radial distribution function analysis of the Fast-Fourier Transform of (<b>d</b>) which shows a single extracted peak in spatial frequency at around 2.8 μm<sup>−1</sup>. (<b>f</b>) shows a layer-by-layer dynamic light scattering (DLS) analysis of the growth of core-interlayer-shell particles, giving a final diameter of ≈350nm.</p>
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<p>Broadband normal incidence Vis-NIR spectra for PO thin-film samples spanning the core-interlayer-shell (CIS) diameter range of 330 to 510 nm, with increasing size from top (Sample 1) to bottom (Sample 5). The positions of the transmission-dip features are indicated by arrow in (<b>c</b>,<b>d</b>) for clarity. The film thicknesses, as measured with a Vernier external micro-meter, are indicated in the insets.</p>
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<p>(<b>a</b>) The transmission spectra across the visible and NIR of an 80 µm thick infrared polymer opal on 100 µm PET substrate with a normal incidence (<math display="inline"><semantics> <mrow> <msub> <mi>θ</mi> <mi>I</mi> </msub> </mrow> </semantics></math> = 0) bandgap around 800 nm (Sample 2). This is seen to blue-shift with increasing incidence angle from the normal, as shown by the legend. (<b>b</b>) The commensurate reflectivity spectra of samples processed 40-BIOS cycles are, illustrating the angular tuning and anisotropy with ±<math display="inline"><semantics> <mrow> <msub> <mi>θ</mi> <mi>I</mi> </msub> </mrow> </semantics></math> (see legend).</p>
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<p>The scattering cones of reflectance for (<b>a</b>) 5, (<b>b</b>) 10, (<b>c</b>) 20, and (<b>d</b>) 40 BIOS shear pass polymer opals (Sample 2). Light is incident normal to the surface (<math display="inline"><semantics> <mrow> <msub> <mi>θ</mi> <mi>I</mi> </msub> </mrow> </semantics></math> = 0), with the BIOS direction vector <math display="inline"><semantics> <mover accent="true"> <mi>p</mi> <mo stretchy="false">^</mo> </mover> </semantics></math> aligned parallel to the illumination plane. Viewing is in the plane <math display="inline"><semantics> <mrow> <msub> <mi>φ</mi> <mi>m</mi> </msub> </mrow> </semantics></math>= 0°, which lies perpendicular to the illumination and ĝ direction. Measurements of viewing angle spectra (<math display="inline"><semantics> <mrow> <msub> <mi>θ</mi> <mi>m</mi> </msub> </mrow> </semantics></math>) are given in 10° increments. Reflectance is given on the z-axis as a percentage for a common scale, inset in (<b>a</b>).</p>
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<p>A schematic diagram of the bespoke goniometric set-up, with key components indicated. The shaded detectors illustrate potential placements, with full 360° capabilities. The shear-processing direction is indicated by the vector <math display="inline"><semantics> <mover accent="true"> <mi>p</mi> <mo stretchy="false">^</mo> </mover> </semantics></math>. Inset: the spherical co-ordinate system, defining illumination angle from the normal in the plane of incidence (<math display="inline"><semantics> <mrow> <msub> <mi>θ</mi> <mi>I</mi> </msub> </mrow> </semantics></math>), detection azimuth relative the plane of incidence (<math display="inline"><semantics> <mrow> <msub> <mi>φ</mi> <mi>m</mi> </msub> </mrow> </semantics></math>) and detection angle from the normal (<math display="inline"><semantics> <mrow> <msub> <mi>θ</mi> <mi>m</mi> </msub> </mrow> </semantics></math>).</p>
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<p>The scattering cones of 40 BIOS shear pass polymer opals with a normal incidence stopband at approximately 800 nm. This is seen to tune for illumination (<math display="inline"><semantics> <mrow> <msub> <mi>θ</mi> <mi>I</mi> </msub> </mrow> </semantics></math>) at 15° (<b>a</b>–<b>d</b>) and 30° (<b>e</b>–<b>h</b>) displaced from the zenith, for a range of azimuthal viewing planes (<math display="inline"><semantics> <mrow> <msub> <mi>φ</mi> <mi>m</mi> </msub> </mrow> </semantics></math>) close to the forward scattering cone centred on <math display="inline"><semantics> <mrow> <msub> <mi>φ</mi> <mi>m</mi> </msub> </mrow> </semantics></math> = 90°.</p>
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19 pages, 2954 KiB  
Protocol
Optimizing Recombinant Cas9 Expression: Insights from E. coli BL21(DE3) Strains for Enhanced Protein Purification and Genome Editing
by Shilpi Agrawal, Made Harumi Padmaswari, Abbey L. Stokes, Daniel Maxenberger, Morgan Reese, Adila Khalil and Christopher E. Nelson
Biomedicines 2024, 12(6), 1226; https://doi.org/10.3390/biomedicines12061226 - 31 May 2024
Viewed by 1698
Abstract
The CRISPR-Cas9 system is a revolutionary tool in genetic engineering, offering unprecedented precision and efficiency in genome editing. Cas9, an enzyme derived from bacteria, is guided by RNA to edit DNA sequences within cells precisely. However, while CRISPR-Cas9 presents notable benefits and encouraging [...] Read more.
The CRISPR-Cas9 system is a revolutionary tool in genetic engineering, offering unprecedented precision and efficiency in genome editing. Cas9, an enzyme derived from bacteria, is guided by RNA to edit DNA sequences within cells precisely. However, while CRISPR-Cas9 presents notable benefits and encouraging outcomes as a molecular tool and a potential therapeutic agent, the process of producing and purifying recombinant Cas9 protein remains a formidable hurdle. In this study, we systematically investigated the expression of recombinant SpCas9-His in four distinct Escherichia coli (E. coli) strains (Rosetta2, BL21(DE3), BL21(DE3)-pLysS, and BL21(DE3)-Star). Through optimization of culture conditions, including temperature and post-induction time, the BL21(DE3)-pLysS strain demonstrated efficient SpCas9 protein expression. This study also presents a detailed protocol for the purification of recombinant SpCas9, along with detailed troubleshooting tips. Results indicate successful SpCas9 protein expression using E. coli BL21(DE3)-pLysS at 0.5 mM IPTG concentration. Furthermore, the findings suggest potential avenues for further enhancements, paving the way for large-scale Cas9 production. This research contributes valuable insights into optimizing E. coli strains and culture conditions for enhanced Cas9 expression, offering a step forward in the development of efficient genome editing tools and therapeutic proteins. Full article
(This article belongs to the Section Molecular and Translational Medicine)
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<p>Comparative depiction of competent cells used in this study, including (<b>A</b>) BL21(DE3), (<b>B</b>) BL21(DE3)-Star, (<b>C</b>) Rosetta2, and (<b>D</b>) BL21(DE3)-pLysS.</p>
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<p>(<b>A</b>) Genetic map of pET-28b-Cas9-His obtained from Addgene. (<b>B</b>) Transcriptional unit of SpCas9-NLS-6His.</p>
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<p>Schematic representation illustrating the sequential steps involved in the purification of SpCas9-His protein using Ni-Sepharose resin and an imidazole gradient.</p>
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<p>In vitro analysis of RNP (Ribonucleoprotein) complex assembly.</p>
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<p>Evaluation of the effects of IPTG concentration and induction temperature on the expression of SpCas9-His protein in BL21(DE3)-pLysS strain of <span class="html-italic">E. coli</span>. (<b>A</b>) SDS-PAGE analysis of the expression of SpCas9-His protein at 0.5 mM IPTG at 18 °C overnight. (<b>B</b>) SDS-PAGE analysis of the expression of SpCas9-His protein at 30 °C but at different IPTG concentrations (lane 1—0.5 mM IPTG, lane 2—protein ladder, lane 3—1 mM IPTG conc); (<b>C</b>) Expression of SpCas9-His protein at different induction temperatures (18, 25, 30, and 37 °C).</p>
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<p>Assessment of SpCas9-His protein expression in BL21(DE3)-pLysS, BL21(DE3)-Star, Rosetta2, and BL21(DE3) cells induced with 0.5 mM IPTG at 30 °C for 6 h in LB medium. Legend—1 and 4: Cell lysate before induction; 2 and 5: Cell lysate post-induction; 3—Protein marker.</p>
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<p>Evaluation of SpCas9-His protein expression in BL21(DE3)-pLysS induced with 0.5 mM IPTG. (<b>A</b>) Protein purification profile of SpCas9-His using Ni-Sepharose affinity chromatography. 1: protein ladder; 2—fraction from the wash step; 3—first 5 mL of the fraction from the elution step. This is an important step as it gets rid of the lower contamination and 4—remaining fraction from the elution step. (<b>B</b>) SDS PAGE gel after buffer exchange to ensure pure protein. 1: protein ladder; 2—pure protein after buffer exchange. (<b>C</b>) Western blot analysis of SpCas9-His expression. Legend: SpCas9-His protein and pre-stained protein MW marker.</p>
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<p>(<b>A</b>) In vitro cleavage assay. Only a complex of SpCas9 and gRNA could digest the plasmid DNA. “C” represents commercial Cas9, while “IH” represents in-house Cas9. The numbers 30 and 60 denote the ratio of gRNA:SpCas9:DNA. For instance, 30 corresponds to a ratio of 30:30:1 (nM), and 60 corresponds to a ratio of 60:60:1 (nM). (<b>B</b>) The densitometric analysis of in vitro digestion assay of the cleaved DNA (784 bp) band, as monitored by agarose gel electrophoresis.</p>
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25 pages, 7113 KiB  
Article
LidPose: Real-Time 3D Human Pose Estimation in Sparse Lidar Point Clouds with Non-Repetitive Circular Scanning Pattern
by Lóránt Kovács, Balázs M. Bódis and Csaba Benedek
Sensors 2024, 24(11), 3427; https://doi.org/10.3390/s24113427 - 26 May 2024
Cited by 1 | Viewed by 988
Abstract
In this paper, we propose a novel, vision-transformer-based end-to-end pose estimation method, LidPose, for real-time human skeleton estimation in non-repetitive circular scanning (NRCS) lidar point clouds. Building on the ViTPose architecture, we introduce novel adaptations to address the unique properties of NRCS lidars, [...] Read more.
In this paper, we propose a novel, vision-transformer-based end-to-end pose estimation method, LidPose, for real-time human skeleton estimation in non-repetitive circular scanning (NRCS) lidar point clouds. Building on the ViTPose architecture, we introduce novel adaptations to address the unique properties of NRCS lidars, namely, the sparsity and unusual rosetta-like scanning pattern. The proposed method addresses a common issue of NRCS lidar-based perception, namely, the sparsity of the measurement, which needs balancing between the spatial and temporal resolution of the recorded data for efficient analysis of various phenomena. LidPose utilizes foreground and background segmentation techniques for the NRCS lidar sensor to select a region of interest (RoI), making LidPose a complete end-to-end approach to moving pedestrian detection and skeleton fitting from raw NRCS lidar measurement sequences captured by a static sensor for surveillance scenarios. To evaluate the method, we have created a novel, real-world, multi-modal dataset, containing camera images and lidar point clouds from a Livox Avia sensor, with annotated 2D and 3D human skeleton ground truth. Full article
(This article belongs to the Section Optical Sensors)
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<p>Point cloud sample recorded on the same scene with different integration times using the NRCS lidar. The sparse point cloud can be seen on the left, while a denser cloud is visible on the right. Note that while increased integration time brings more density, it also introduces motion blur on dynamic objects, as shown with the moving pedestrian marked with the red rectangle. The pedestrian’s points are colored with the lidar intensity, the background is colored by the y-axis value.</p>
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<p>Non-repetitive circular scanning (NRCS) lidar point cloud with 100 ms integration time represented as a 2D range image overlaid on a sample camera image. NRCS lidar point cloud is colored by the distance: the lighter the point’s color, the greater its distance.</p>
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<p><span class="html-italic">LidPose</span> end-to-end solution. Lidar data: full lidar point cloud. Select RoI: selects the 3D points in the vicinity of the observed human. Projection stores the 3D point cloud in a 2D array. Input types: 3D XYZ coordinates (<tt>XYZ</tt>), depth (<tt>D</tt>), and intensity (<tt>I</tt>). LidPose network: both <span class="html-italic">LidPose–2D</span> and <span class="html-italic">LidPose–3D</span> use our patch-embedding module and the encoder backbone visible in blue. <span class="html-italic">LidPose–2D</span> and <span class="html-italic">LidPose–3D</span> use the corresponding decoder head and <span class="html-italic">LidPose–2D+</span> is calculated from the 2D prediction and the input point cloud.</p>
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<p>Predicted human poses of the <span class="html-italic">LidPose</span> variants, overlaid on the input data. (<b>a</b>) LidPose–2D: 2D predicted skeleton (red) over the 2D lidar point cloud representation (colored based on 3D coordinate value). (<b>b</b>) LidPose–2D+: 2D predicted skeleton (red) is extended to the 3D space using the lidar points (gray) where they are available. Points where lidar measurements are not available are highlighted in blue. (<b>c</b>) LidPose–3D: 3D predicted skeleton (red) over the lidar point cloud (gray).</p>
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<p>Distribution of the joints recorded in the <span class="html-italic">LidPose dataset</span>, based on the local emergence angle of the lidar sensor.</p>
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<p>Distribution of the joints in the <span class="html-italic">LidPose dataset</span>, based on the depth coordinate (<span class="html-italic">X</span>) of the 3D joints.</p>
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<p>Distribution of 2D joint coordinate positions in the test dataset overlaid on a sample camera image.</p>
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<p>Distribution of joint positions in the <span class="html-italic">LidPose dataset</span>, displayed on the ground plane <math display="inline"><semantics> <msub> <mrow> <mo>(</mo> <mi>X</mi> <mo>,</mo> <mi>Y</mi> <mo>)</mo> </mrow> <mrow> <mn>3</mn> <mi>D</mi> </mrow> </msub> </semantics></math> from a bird’s-eye view.</p>
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<p><span class="html-italic">LidPose–2D</span>: Percentage of correct keypoints for the different 2D networks with different joint-correspondence threshold acceptance values. Model <span class="html-italic">2D–4</span>, which is trained on 3D coordinates + lidar intensity, has the best PCK curve.</p>
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<p>Example training batch of input data with the randomly applied augmentations (horizontal mirroring, scaling, rotation, half-body transform). The camera images are shown for visual reference only.</p>
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<p><span class="html-italic">LidPose–2D</span> prediction examples are shown in subfigures (<b>a</b>–<b>f</b>) for different samples from the dataset. The predictions are shown in red, overlaid on the input lidar point cloud (right). The corresponding camera frame, and the ground truth is shown in green (left). The prediction and the ground truth are shown together overlaid on the camera image (middle).</p>
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<p>2D average distance error (ADE) of the selected <span class="html-italic">2D–4</span> model, overlaid on a sample camera image.</p>
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<p>PCK and AUC-PCK values of the 3D predictions by LidPose–3D and LidPose–2D+ networks evaluated in 3D space with 3D metrics. The <span class="html-italic">AUC-PCK</span> was calculated on the [0, 0.5]-meter interval, as shown in <a href="#sensors-24-03427-f014" class="html-fig">Figure 14</a>.</p>
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<p><span class="html-italic">LidPose–3D</span>: percentage of correct keypoints (PCK) in the 3D space for the different 3D (and 2D+) networks with different joint-correspondence threshold distance acceptance values. <span class="html-italic">Model 3D-9</span>, which has been trained on 3D coordinates + lidar intensity with SSIM-based depth loss, has the best PCK curve.</p>
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<p>Distribution of average distance error (ADE) of the predicted joints in bird’s eye view using the selected <span class="html-italic">3D–09</span> model. Only cells with more than 24 annotated joints are shown.</p>
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<p><span class="html-italic">LidPose3D</span> prediction examples are shown in subfigures (<b>a</b>–<b>d</b>) for different samples from the dataset, using the <span class="html-italic">3D–09</span> model. Red skeleton: 3D prediction. Green skeleton: ground truth. Gray points: NRCS lidar points.</p>
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13 pages, 5016 KiB  
Article
Cloning, Expression, Purification, and Characterization of Lactate Dehydrogenase from Plasmodium knowlesi: A Zoonotic Malaria Parasite
by Jae-Won Choi, Min-Ji Choi, Yeon-Jun Kim and So Yeon Kim
Int. J. Mol. Sci. 2024, 25(11), 5615; https://doi.org/10.3390/ijms25115615 - 22 May 2024
Viewed by 869
Abstract
Plasmodium knowlesi is the only Plasmodium that causes zoonotic disease among the Plasmodium that cause infection in humans. It is fatal due to its short asexual growth cycle within 24 h. Lactate dehydrogenase (LDH), an enzyme that catalyzes the final step of glycolysis, [...] Read more.
Plasmodium knowlesi is the only Plasmodium that causes zoonotic disease among the Plasmodium that cause infection in humans. It is fatal due to its short asexual growth cycle within 24 h. Lactate dehydrogenase (LDH), an enzyme that catalyzes the final step of glycolysis, is a biomarker for diagnosing infection by Plasmodium spp. parasite. Therefore, this study aimed to efficiently produce the soluble form of P. knowlesi LDH (PkLDH) using a bacterial expression system for studying malaria caused by P. knowlesi. Recombinant pET-21a(+)-PkLDH plasmid was constructed by inserting the PkLDH gene into a pET-21a(+) expression vector. Subsequently, the recombinant plasmid was inserted into the protein-expressing Escherichia coli Rosetta(DE3) strain, and the optimal conditions for overexpression of the PkLDH protein were established using this strain. We obtained a yield of 52.0 mg/L PkLDH from the Rosetta(DE3) strain and confirmed an activity of 483.9 U/mg through experiments. This methodology for high-efficiency PkLDH production can be utilized for the development of diagnostic methods and drug candidates for distinguishing malaria caused by P. knowlesi. Full article
(This article belongs to the Special Issue Recombinant Proteins, Protein Folding and Drug Discovery)
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<p>Amino acid identity of major <span class="html-italic">Plasmodium</span> spp. LDH. (<b>a</b>) Table comparing amino acid sequence (316 amino acids) of PfLDH and PvLDH with those of PkLDH, respectively. Red boxes indicate areas where PkLDH differs from the amino acids of PfLDH and PvLDH. (<b>b</b>) Percent identity of amino acid sequence of PkLDH with PfLDH and PvLDH. PfLDH and PvLDH exhibited 90.51% and 95.25% identity with PkLDH, respectively. PfLDH, <span class="html-italic">Plasmodium falciparum</span> lactate dehydrogenase; PvLDH, <span class="html-italic">Plasmodium vivax</span> lactate dehydrogenase; PkLDH, <span class="html-italic">Plasmodium knowlesi</span> lactate dehydrogenase.</p>
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<p>Construction of pET-21a(+)-<span class="html-italic">PkLDH</span> for recombinant PkLDH production. (<b>a</b>) Plasmid map of pET-21a(+)-<span class="html-italic">PkLDH</span>. <span class="html-italic">PkLDH</span> gene from the pUC-IDT-<span class="html-italic">PkLDH</span> was inserted into the <span class="html-italic">Xho</span>I and <span class="html-italic">Eco</span>RI restriction sites of pET-21a(+). Recombinant plasmid was introduced into DH5α strain for subcloning. (<b>b</b>) An agarose gel image of digested plasmid construct from DH5α strain with <span class="html-italic">Xho</span>I and <span class="html-italic">Eco</span>RI restriction enzymes. Gel electrophoresis was performed on a 0.8% agarose gel. (<b>c</b>) An agarose gel image of PCR product of plasmid construct using DH5α strain with <span class="html-italic">PkLDH</span>-specific primers. Electrophoresis was performed on a 1.2% agarose gel.</p>
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<p>Overexpression pattern of PkLDH according to temperature and IPTG concentration. (<b>a</b>) A polyacrylamide gel image after sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of lysate from the transformed <span class="html-italic">E. coli</span> Rosetta(DE3) induced at 18 °C for 16 h. (<b>b</b>) A polyacrylamide gel image of lysate from the transformed <span class="html-italic">E. coli</span> Rosetta(DE3) induced at 24 °C for 12 h. (<b>c</b>) A polyacrylamide gel image of lysate from transformed <span class="html-italic">E. coli</span> Rosetta(DE3) induced at 30 °C for 4 h. All three experiments were performed under same SDS-PAGE conditions. Overexpression of PkLDH was induced using different concentrations of IPTG (0, 0.001, 0.005, 0.01, 0.05, 0.1, 0.5, and 1 mM). SDS-PAGE was performed on a 12% separating gel. Arrow to the right of each gel indicates overexpressed PkLDH protein.</p>
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<p>Overexpression pattern of PkLDH according to time at different temperatures. (<b>a</b>) A polyacrylamide gel image after SDS-PAGE of lysate from the transformed <span class="html-italic">E. coli</span> Rosetta(DE3) induced at 18 °C for 16 h. Bacterial cells collected hourly. (<b>b</b>) A polyacrylamide gel image of lysate from the transformed <span class="html-italic">E. coli</span> Rosetta(DE3) induced at 24 °C for 12 h. Bacterial cells were collected every hour. (<b>c</b>) A polyacrylamide gel image of lysate from transformed <span class="html-italic">E. coli</span> Rosetta(DE3) induced at 30 °C for 4 h. Bacterial cells were collected every 20 min. All three experiments were performed under the same SDS-PAGE conditions. Overexpression of PkLDH was induced using 0.1 mM of IPTG. SDS-PAGE was performed on a 12% separating gel. Arrow to right of each gel indicates the overexpressed PkLDH protein.</p>
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<p>Purification process of recombinant PkLDH by affinity chromatography using a Ni-NTA resin. SDS-PAGE results for all fractions of affinity chromatography starting from sample preparation process for purification of recombinant PkLDH. Gel images show differences in PkLDH overexpression pre-induction (Pre) and post-induction (Post) sample. Additionally, pellet and supernatant (Sup) obtained by centrifugation after bacterial lysis show that most of the PkLDH is present in the supernatant. FT represents the flow-through fraction obtained by loading a bacteria lysate sample. W1 to W30 represent washing fractions that were sequentially passed through Ni-NTA resin by adding washing buffer. E1 to E9 represent elution fractions that were sequentially passed through Ni-NTA resin by adding elution buffer. In all gels, SDS-PAGE was performed on a 12% separating gel under denaturation conditions.</p>
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<p>Polyacrylamide gel electrophoresis for confirmation of PkLDH purity and tetramer formation. (<b>a</b>) A polyacrylamide gel image confirming the monomer form and purity of PkLDH. SDS-PAGE was performed on a 12% separating gel under denaturation (reducing) conditions. (<b>b</b>) A polyacrylamide gel image confirming tetramer formation and molecular weight of the PkLDH tetramer. At this time, PkLDH was prepared under native (non-reducing) conditions in a buffer without SDS. PAGE was performed on a 10% separating gel without SDS.</p>
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<p>Colorimetric assay for measurement of PkLDH activity. (<b>a</b>) Standard curve by mixing different amounts of NADH (0, 2.5, 5.0, 7.5, 10.0, and 12.5 nmole) and substrate mixture. The total reaction volume was 100 μL and absorbance was measured at 450 nm and 37 °C. Inset image shows the yellow product according to different amounts of NADH, and the greater the amount of NADH, the more products there are, so the yellow color becomes darker. (<b>b</b>) Colorimetric LDH assay according to different final concentrations of PkLDH (0, 0.01, 0.02, 0.03, 0.06, 0.13, 0.25, and 0.50 nM). Total reaction volume was 100 μL, and absorbance was measured at 450 nm and 37 °C. Absorbance was measured at 10 min and 30 min after reaction for each concentration in triplicates.</p>
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14 pages, 4941 KiB  
Article
Characterization of Escherichia coli Strains for Novel Production of Plasmodium ovale Lactate Dehydrogenase
by Jae-Won Choi, Sang-Oh Ha, Yeon-Jun Kim, Jun-Seop Shin, Min-Ji Choi, Si-Eun Yu, Junghun Han, Eun-Ji Park, Kyoung Sik Park and Jung Hoon Kang
Microorganisms 2024, 12(5), 876; https://doi.org/10.3390/microorganisms12050876 - 27 Apr 2024
Cited by 1 | Viewed by 930
Abstract
Malaria is one of the most prevalent diseases worldwide with high incidence and mortality. Among the five species that can infect humans, Plasmodium ovale morphologically resembles Plasmodium vivax, resulting in misidentification and confusion in diagnosis, and is responsible for malarial disease relapse [...] Read more.
Malaria is one of the most prevalent diseases worldwide with high incidence and mortality. Among the five species that can infect humans, Plasmodium ovale morphologically resembles Plasmodium vivax, resulting in misidentification and confusion in diagnosis, and is responsible for malarial disease relapse due to the formation of hypnozoites. P. ovale receives relatively less attention compared to other major parasites, such as P. falciparum and P. vivax, primarily due to its lower pathogenicity, mortality rates, and prevalence rates. To efficiently produce lactate dehydrogenase (LDH), a major target for diagnosing malaria, this study used three Escherichia coli strains, BL21(DE3), BL21(DE3)pLysS, and Rosetta(DE3), commonly used for recombinant protein production. These strains were characterized to select the optimal strain for P. ovale LDH (PoLDH) production. Gene cloning for recombinant PoLDH production and transformation of the three strains for protein expression were performed. The optimal PoLDH overexpression and washing buffer conditions in nickel-based affinity chromatography were established to ensure high-purity PoLDH. The yields of PoLDH expressed by the three strains were as follows: BL21(DE3), 7.6 mg/L; BL21(DE3)pLysS, 7.4 mg/L; and Rosetta(DE3), 9.5 mg/L. These findings are expected to be highly useful for PoLDH-specific diagnosis and development of antimalarial therapeutics. Full article
(This article belongs to the Special Issue Advances in Microbial Cell Factories, 2nd Edition)
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Graphical abstract

Graphical abstract
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<p>Plasmid construction for recombinant PoLDH production. (<b>a</b>) Schematic diagram of plasmid construction with <span class="html-italic">PoLDH</span> cDNA. The <span class="html-italic">PoLDH</span> gene obtained through PCR from pUC-IDT-<span class="html-italic">PoLDH</span> was introduced through the multiple cloning site of the expression vector pET-21a(+). Through digestion with restriction enzymes (<span class="html-italic">Bam</span>HI and <span class="html-italic">Xho</span>I) and ligation with T4 ligase, recombinant pET-21a(+)-<span class="html-italic">PoLDH</span> was constructed to produce recombinant PoLDH. (<b>b</b>) Identification of purified recombinant pET-21a(+)-<span class="html-italic">PoLDH</span> extracted from the DH5α strain. An agarose gel image of the purified plasmid extracted from the DH5α strain after digestion with both restriction enzymes (<span class="html-italic">Bam</span>HI and <span class="html-italic">Xho</span>I). Gel electrophoresis was performed on a 0.7% agarose gel.</p>
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<p>Optimization of IPTG concentration for PoLDH expression. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) images of PoLDH expressed from (<b>a</b>) BL21(DE3), (<b>b</b>) BL21(DE3)pLysS, and (<b>c</b>) Rosetta(DE3) according to IPTG concentration. All three experiments were conducted at IPTG concentrations of 0, 0.001, 0.005, 0.01, 0.05, 0.1, 0.5, and 1 mM and incubation conditions at 18 °C and 200 rpm for 16 h. Arrows on the right side of the gel indicate overexpressed PoLDH. PL, protein ladder.</p>
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<p>Expression patterns of PoLDH according to IPTG induction time for the three <span class="html-italic">E. coli</span> strains. SDS-PAGE images of PoLDH expressed from (<b>a</b>) BL21(DE3), (<b>b</b>) BL21(DE3)pLysS, and (<b>c</b>) Rosetta(DE3) according to IPTG induction time. All three experiments were conducted with an IPTG concentration of 0.1 mM and incubation conditions of 18 °C and 200 rpm for 16 h. Arrows on the right side of the gel indicate overexpressed PoLDH. PL, protein ladder.</p>
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<p>Elution patterns of PoLDH according to the concentration of imidazole in the washing buffer. SDS-PAGE images of the elution fractions with (<b>a</b>) 10 mM, (<b>b</b>) 20 mM, (<b>c</b>) 30 mM, and (<b>d</b>) 40 mM imidazole in washing buffer. Otherwise, all experiments were performed under the same conditions. The eluted PoLDH was expressed from the Rosetta(DE3) strain. SDS-PAGE was performed on a 12% polyacrylamide gel. Arrows on the right side of the gel indicate PoLDH present in the elution fractions. PL, protein ladder.</p>
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<p>Analysis of fractions obtained from the purification process of PoLDH expressed from the three <span class="html-italic">E. coli</span> strains. SDS-PAGE images of fractions from the purification of PoLDH expressed from (<b>a</b>) BL21(DE3), (<b>b</b>) BL21(DE3)pLysS, and (<b>c</b>) Rosetta(DE3). All experiments were performed under the same conditions. SDS-PAGE was performed on a 12% polyacrylamide gel. PL, protein ladder; Pre-Ind, pre-induction; Post-Ind, post-induction; Sup, supernatant; FT, flow-through.</p>
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<p>PAGE analysis to confirm the purity and tetramer formation of purified PoLDH. (<b>a</b>) SDS-PAGE image confirming the monomer formation and purity of PoLDH. SDS-PAGE was performed on a 12% polyacrylamide gel. (<b>b</b>) Native PAGE image confirming the tetramer formation of PoLDH. The purified PoLDH was mixed with an SDS-free sample buffer and loaded onto an SDS-free 10% polyacrylamide gel. PL, protein ladder.</p>
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<p>Analysis of the purified PoLDH enzyme activity. (<b>a</b>) Standard curve of different amounts of NADH (0, 2.5, 5.0, 7.5, 10.0, and 12.5 nmole). The upper left inset image shows color change with the amount of NADH. (<b>b</b>) Absorbance measurement for each time unit (10 and 30 min) at different final concentrations of PoLDH (0, 0.02, 0.03, 0.06, 0.13, 0.25, and 0.50 nM). Absorbance was measured at a wavelength of 450 nm, 10 min and 30 min after the reaction at 37 °C.</p>
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<p>Amino acid sequence homology analysis of PoLDH, PfLDH, and PvLDH. (<b>a</b>) The amino acid sequences of PoLDH, PfLDH, and PvLDH. PoLDH consists of 310 amino acids, while PfLDH and PvLDH consist of 316 amino acids each. When the same amino acid exists at the same position, it is highlighted in purple, and the homology was analyzed using the UniProt homology analysis tool. (<b>b</b>) The homology matrix for PoLDH, PfLDH, and PvLDH. PoLDH showed 90.32% homology with PfLDH and 98.06% homology with PvLDH.</p>
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17 pages, 2436 KiB  
Article
An Approach for Engineering Peptides for Competitive Inhibition of the SARS-COV-2 Spike Protein
by Ana Paula de Abreu, Frederico Chaves Carvalho, Diego Mariano, Luana Luiza Bastos, Juliana Rodrigues Pereira Silva, Leandro Morais de Oliveira, Raquel C. de Melo-Minardi and Adriano de Paula Sabino
Molecules 2024, 29(7), 1577; https://doi.org/10.3390/molecules29071577 - 1 Apr 2024
Cited by 1 | Viewed by 1225
Abstract
SARS-CoV-2 is the virus responsible for a respiratory disease called COVID-19 that devastated global public health. Since 2020, there has been an intense effort by the scientific community to develop safe and effective prophylactic and therapeutic agents against this disease. In this context, [...] Read more.
SARS-CoV-2 is the virus responsible for a respiratory disease called COVID-19 that devastated global public health. Since 2020, there has been an intense effort by the scientific community to develop safe and effective prophylactic and therapeutic agents against this disease. In this context, peptides have emerged as an alternative for inhibiting the causative agent. However, designing peptides that bind efficiently is still an open challenge. Here, we show an algorithm for peptide engineering. Our strategy consists of starting with a peptide whose structure is similar to the interaction region of the human ACE2 protein with the SPIKE protein, which is important for SARS-COV-2 infection. Our methodology is based on a genetic algorithm performing systematic steps of random mutation, protein–peptide docking (using the PyRosetta library) and selecting the best-optimized peptides based on the contacts made at the peptide–protein interface. We performed three case studies to evaluate the tool parameters and compared our results with proposals presented in the literature. Additionally, we performed molecular dynamics (MD) simulations (three systems, 200 ns each) to probe whether our suggested peptides could interact with the spike protein. Our results suggest that our methodology could be a good strategy for designing peptides. Full article
(This article belongs to the Topic Bioinformatics in Drug Design and Discovery—2nd Edition)
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Figure 1

Figure 1
<p>Interface interactions between ACE2 (cyan cartoon) and the spike receptor (green cartoon). Residues from ACE2 closer to the spike are shown as orange sticks (PDB ID: 6M0J). Blue: nitrogen atoms; red: oxygen atoms. The figure was generated using Open-Source PyMOL Version 2.5 (Schrödinger, LLC, New York, NY, USA).</p>
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<p>POTTER algorithm overview using the following parameters: G = 5, M = 6, and R = 3.</p>
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<p>Frames 0 (0 ns), 5000 (100 ns), and 9999 (200 ns) from the three MD simulations: spike complexed with the peptide template (<b>top</b>); spike complexed with the LDS peptide (<b>middle</b>); and spike complexed with the HO peptide (<b>bottom</b>).</p>
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<p>The hydrogen bonds are formed between the peptide template and the receptor, as well as between the manually curated peptide and the receptor. Figure generated using ChimeraX version 1.4.</p>
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<p>Best peptide selected by generation for case studies 1, 2, and 3. The generation in which each best peptide is obtained is highlighted by a red arrow.</p>
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<p>2D-RMSD, RMDS, and RMSF line plots for the three MD simulations: spike complexed with the peptide template (<b>A</b>,<b>D</b>,<b>G</b>, respectively); spike complexed with the LDS peptide (<b>B</b>,<b>E</b>,<b>H</b>, respectively); and spike complexed with the HO peptide (<b>C</b>,<b>F</b>,<b>I</b>, respectively).</p>
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<p>POTTER method workflow.</p>
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