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    Feng Chen

    Algal-virus-specific PCR primers were used to amplify DNA polymerase gene (pol) fragments (683 to 689 bp) from the virus-sized fraction (0.02 to 0.2 microns) concentrated from inshore and offshore water samples collected from the Gulf of... more
    Algal-virus-specific PCR primers were used to amplify DNA polymerase gene (pol) fragments (683 to 689 bp) from the virus-sized fraction (0.02 to 0.2 microns) concentrated from inshore and offshore water samples collected from the Gulf of Mexico. Algal-virus-like DNA pol genes were detected in five samples collected from the surface and deep chlorophyll maximum. PCR products from an offshore station were cloned, and the genetic diversity of 33 fragments was examined by restriction fragment length polymorphism and sequence analysis. The five different genotypes or operational taxonomic units (OTUs) that were identified on the basis of restriction fragment length polymorphism banding patterns were present in different relative abundances (9 to 34%). One clone from each OTU was sequenced, and phylogenetic analysis showed that all of the OTUs fell within the family Phycodnaviridae. Four of the OTUs fell within a group of viruses (MpV) which infect the photosynthetic picoplankter Micromon...
    Orthology detection is critically important for accurate functional annotation, and has been widely used to facilitate studies on comparative and evolutionary genomics. Although various methods are now available, there has been no... more
    Orthology detection is critically important for accurate functional annotation, and has been widely used to facilitate studies on comparative and evolutionary genomics. Although various methods are now available, there has been no comprehensive analysis of performance, due to the lack of a genomic-scale 'gold standard' orthology dataset. Even in the absence of such datasets, the comparison of results from alternative methodologies contains useful information, as agreement enhances confidence and disagreement indicates possible errors. Latent Class Analysis (LCA) is a statistical technique that can exploit this information to reasonably infer sensitivities and specificities, and is applied here to evaluate the performance of various orthology detection methods on a eukaryotic dataset. Overall, we observe a trade-off between sensitivity and specificity in orthology detection, with BLAST-based methods characterized by high sensitivity, and tree-based methods by high specificity...
    A novel isolate of infectious bursal disease virus (IBDV) was designated GX-NN-L. The GX-NN-L IBDV was a very virulent infectious bursal disease virus (vvIBDV) isolated from broiler flocks in Guangxi province, China, in 2011. The GX-NN-L... more
    A novel isolate of infectious bursal disease virus (IBDV) was designated GX-NN-L. The GX-NN-L IBDV was a very virulent infectious bursal disease virus (vvIBDV) isolated from broiler flocks in Guangxi province, China, in 2011. The GX-NN-L IBDV caused high mortality, immunosuppression, low weight gain, and bursal atrophy in commercial broilers. Here, we report the complete genome sequence of the GX-NN-L IBDV, a reassortment strain with segments A and B derived from very virulent strains and attenuated IBDV, respectively. These findings from this study provide additional insights into the genetic exchange between attenuated and very virulent strains of IBDV and continuous monitoring of the spread of the virus in chicken.
    In 2010 and 2011, several devastating Newcastle disease (ND) outbreaks occurred in China, affecting broilers, layers, and breeders. The CK-JSX1-201005 virus was isolated from broiler breeder flocks vaccinated with the classical ND virus... more
    In 2010 and 2011, several devastating Newcastle disease (ND) outbreaks occurred in China, affecting broilers, layers, and breeders. The CK-JSX1-201005 virus was isolated from broiler breeder flocks vaccinated with the classical ND virus (NDV) vaccine program, but laying rate decreased from 80% to 30 to 40% in the clinic. Here, we report the complete genome sequence and molecular characteristic of the CK-JSX1-201005 NDV. These findings provide additional insights into the genetic variation of NDV circulating in China and are useful for vaccine development for NDV.
    Arabidopsis is emerging as a model system to study the biochemistry, biological functions, and evolution of plant terpene secondary metabolism. It was previously shown that the Arabidopsis genome contains over 30 genes potentially... more
    Arabidopsis is emerging as a model system to study the biochemistry, biological functions, and evolution of plant terpene secondary metabolism. It was previously shown that the Arabidopsis genome contains over 30 genes potentially encoding terpene synthases (TPSs). Here we report the characterization of a monoterpene synthase encoded by two identical, closely linked genes, At3g25820 and At3g25830. Transcripts of these genes
    Accumulative evidence suggests that low folate intake is associated with increased risk of breast cancer. Polymorphisms in genes involved in folate metabolism may influence DNA methylation, nucleotide synthesis, and thus individual... more
    Accumulative evidence suggests that low folate intake is associated with increased risk of breast cancer. Polymorphisms in genes involved in folate metabolism may influence DNA methylation, nucleotide synthesis, and thus individual susceptibility to cancer. Thymidylate synthase (TYMS) is a key enzyme that participates in folate metabolism and catalyzes the conversion of dUMP to dTMP in the process of DNA synthesis. Two potentially functional polymorphisms [a 28-bp tandem repeat in the TYMS 5'-untranslated enhanced region (TSER) and a 6-bp deletion/insertion in the TYMS 3'-untranslated region (TS 3'-UTR)] were suggested to be correlated with alteration of thymidylate synthase expression and associated with cancer risk. To test the hypothesis that polymorphisms of the TYMS gene are associated with risk of breast cancer, we genotyped these two polymorphisms in a case-control study of 432 incident cases with invasive breast cancer and 473 cancer-free controls in a Chinese po...
    Chicken anemia virus (CAV) is an important pathogen that causes severe immunosuppression in young chickens. We have characterized 13 CAVs isolated from different commercial farms in southern China between 2011 and 2012. We discovered 92... more
    Chicken anemia virus (CAV) is an important pathogen that causes severe immunosuppression in young chickens. We have characterized 13 CAVs isolated from different commercial farms in southern China between 2011 and 2012. We discovered 92 variable residues compared to 37 other CAV complete genome sequences from other parts of the world listed in GenBank; these residues have not been previously observed. All of the Chinese CAV genomes that were characterized in this study had a glutamine at position 394, a hallmark of highly pathogenic CAVs. We also discovered that intra-group genetic recombination plays a role in generating genetic diversity in natural populations of CAV. The GD-J-12 isolate was a possible recombinant between GD-C-12 and GD-M-12 in the genomic region that encompassed both the coding and non-coding regions.
    A multiresidue analytical method was developed for the determination of 9 endocrine disrupting chemicals (EDCs) and 19 pharmaceuticals and personal care products (PPCPs) including acidic and neutral pharmaceuticals in water and soil... more
    A multiresidue analytical method was developed for the determination of 9 endocrine disrupting chemicals (EDCs) and 19 pharmaceuticals and personal care products (PPCPs) including acidic and neutral pharmaceuticals in water and soil samples using rapid resolution liquid chromatography-tandem mass spectrometry (RRLC-MS/MS). Solid phase extraction (SPE), and ultrasonic extraction combined with silica gel purification were applied as pretreatment methods for water and soil samples, respectively. The extracts of the EDCs and PPCPs in water and soil samples were then analyzed by RRLC-MS/MS in electrospray ionization (ESI) mode in three independent runs. The chromatographic mobile phases consisted of Milli-Q water and acetonitrile for EDCs and neutral pharmaceuticals, and Milli-Q water containing 0.01 % acetic acid (v/v) and acetonitrile: methanol (1:1, v/v) for acidic pharmaceuticals at a flow rate of 0.3 mL/min. Most of the target compounds exhibited signal suppression due to matrix eff...
    Avian influenza virus (H9N2) infection is a major problem of product performance in poultry worldwide. Vaccination is used to limit spread, but more knowledge is needed on the epidemiology of virus subtypes to improve vaccine design. In... more
    Avian influenza virus (H9N2) infection is a major problem of product performance in poultry worldwide. Vaccination is used to limit spread, but more knowledge is needed on the epidemiology of virus subtypes to improve vaccine design. In this study, 40 H9N2 subtype avian influenza viruses (AIVs) were isolated from vaccinated poultry flocks in China from 2010 to 2011. Hemagglutinin (HA) from different virus strains was sequenced and analyzed. We found that the HA genes of these strains shared nucleotide and deduced amino acid homologies that ranged from 90.1 to 92.9 and 91.4 to 95.0 %, respectively, when compared with vaccine strains. Phylogenetic analysis showed that the strains tested could be divided into two major groups. Group I consisted of 24 strains isolated mainly from Eastern and Central China. Group II consisted of 20 strains isolated from Southern China. The cleavage site within the HA protein contained two basic motifs, PSRSSR↓GLF for group I, and PARSSR↓GLF for group II....
    In this study, we attenuated a Chinese QX-like nephropathogenic infectious bronchitis virus (IBV) strain, YX10, by passaging through fertilized chicken eggs. The 90th passage strain (YX10p90) was selected as the live-attenuated vaccine... more
    In this study, we attenuated a Chinese QX-like nephropathogenic infectious bronchitis virus (IBV) strain, YX10, by passaging through fertilized chicken eggs. The 90th passage strain (YX10p90) was selected as the live-attenuated vaccine candidate strain. YX10p90 was found to be safe in 7-day-old specific pathogen free chickens without induction of morbidity or mortality. YX10p90 provided nearly complete protection against QX-like (CH I genotype) strains and partial protection against other two major Chinese genotype strains. YX10p90 also showed no reversion to virulence after five back passages in chickens. An IBV polyvalent vaccine containing YX10p90 was developed and showed that it could provide better protection against major Chinese IBV virulent strains than commercial polyvalent vaccines. In addition, the complete genome sequence of YX10p90 was sequenced. Multiple-sequence alignments identified 38 nucleotide substitutions in the whole genome which resulted in 26 amino acid subst...
    Early childhood caries (ECC) has become a prevalent public health problem among Chinese preschool children. The bacterial microflora is considered to be an important factor in the formation and progress of dental caries. However,... more
    Early childhood caries (ECC) has become a prevalent public health problem among Chinese preschool children. The bacterial microflora is considered to be an important factor in the formation and progress of dental caries. However, high-throughput and large-scale studies of the primary dentition are lacking. The present study aimed to compare oral microbial profiles between children with severe ECC (SECC) and caries-free children. Both saliva and supragingival plaque samples were obtained from children with SECC (n = 20) and caries-free children (n = 20) aged 3 to 4 years. The samples were assayed using the Human Oral Microbe Identification Microarray (HOMIM). A total of 379 bacterial species were detected in both the saliva and supragingival plaque samples from all children. Thirteen (including Streptococcus) and two (Streptococcus and Actinomyces) bacterial species in supragingival plaque and saliva, respectively, showed significant differences in prevalence between the two groups. ...
    This study investigated the occurrence of 43 emerging contaminants including 9 endocrine-disrupting chemicals and 34 pharmaceuticals in three sites in Hebei Province, north China. Each site has a wastewater irrigated plot and a separate... more
    This study investigated the occurrence of 43 emerging contaminants including 9 endocrine-disrupting chemicals and 34 pharmaceuticals in three sites in Hebei Province, north China. Each site has a wastewater irrigated plot and a separate groundwater irrigated plot for comparison purpose. The results showed that the concentrations of the target compounds in the wastewater irrigated soils were in most cases higher than those in the groundwater irrigated soils. Among the 43 target compounds, nine compounds bisphenol-A, triclocarban, triclosan, 4-nonylphenol, salicylic acid, oxytetracycline, tetracycline, trimethoprim and primidone were detected at least once in the soils. Preliminary environmental risk assessment showed that triclocarban might pose high risks to terrestrial organisms while the other detected compounds posed minimal risks. Irrigation with wastewater could lead to presence or accumulation of some emerging contaminants to some extent in irrigated soils.
    Mutations in the transmembrane receptor patched homolog 1 (Homo sapiens) (ptch1) are responsible for nevoid basal cell carcinoma syndrome (NBCCS), an autosomal dominant disorder that causes developmental abnormalities and predisposes the... more
    Mutations in the transmembrane receptor patched homolog 1 (Homo sapiens) (ptch1) are responsible for nevoid basal cell carcinoma syndrome (NBCCS), an autosomal dominant disorder that causes developmental abnormalities and predisposes the affected individuals to cancer. Many of these mutations, including mutations in the C-terminus of the large intracellular loop (ICL) of ptch1 (p.C727VfsX745 and p.S733IfsX736), result in the premature truncation of the protein. The ptch1‑C727VfsX745 and ptch1-S733IfsX736 mutations have been identified in patients with NBCCS‑associated keratocystic odontogenic tumors (KCOTs). In the present study, we found that the molecular mechanisms regulated by the non-canonical Hedgehog (Hh) signaling pathway through cyclin B1 are involved in the pathogenesis of NBCCS-associated KCOTs. In contrast to wild-type ptch1, ptch1-C727VfsX745 and ptch1‑S733IfsX736 clearly exhibited reduced binding to cyclin B1. Moreover, the cells expressing these two mutations demonstr...
    Today, exosome-related studies have become a focus in science and technology. Recently, three scientists won the Nobel Prize for determining the mechanisms of exosomal transport, making exosomes a promising biomarker system for disease... more
    Today, exosome-related studies have become a focus in science and technology. Recently, three scientists won the Nobel Prize for determining the mechanisms of exosomal transport, making exosomes a promising biomarker system for disease diagnosis and treatment. This review provides a general introduction of exosomes and explores the recent progress on the function, application, isolation, and identification of exosomes as biomarkers in blood and other body fluids, especially in saliva. Detailed information of exosomal proteins and RNAs is discussed in the paper because of their ability to determine the function of exosomes. Due to their noninvasive assessment for quick and convenient diagnosis of diseases, salivary exosomes may well be promising biomarkers.
    The correlation between exposure to lead (PB) and sperm concentrations and testes weight are important in risk assessment of metal toxicity to male reproductive functions. The authors carried out two systematic reviews and meta-analyses... more
    The correlation between exposure to lead (PB) and sperm concentrations and testes weight are important in risk assessment of metal toxicity to male reproductive functions. The authors carried out two systematic reviews and meta-analyses of rats. In addition, a meta-regression analysis was taken to explore a dose-response relationship between the mean difference of testes weight (MDtestes) and available confounding factors.
    A cross-sectional study using the snowball sampling method was conducted in May 2008 to investigate human immunodeficiency virus (HIV) infection status and related high risk factors among men who have sex with men (MSM) in Suzhou city of... more
    A cross-sectional study using the snowball sampling method was conducted in May 2008 to investigate human immunodeficiency virus (HIV) infection status and related high risk factors among men who have sex with men (MSM) in Suzhou city of Jiangsu province. The researchers carried out a face-to-face questionnaire interview among MSM, and collected their blood samples to test for HIV and other sexually transmitted diseases (STDs). Among the 280 respondents, 91.1% had homosexual acts in the past 6 months and 87.5% had multiple homosexual partners; 46.4% had heterosexual sex in the past 6 months and 33.1% had multiple heterosexual partners. The rate of continued condom use was 44.3% in homosexual sex in the past 6 months, while the rate in heterosexual sex was 33.9%. Laboratory test results showed that the prevalences of HIV and syphilis were 7.1% (20/280) and 15.0% (42/280), respectively, but no HCV-positive person was found. In the multivariate logistic regression model, subjects with ...
    The chicken anemia virus (CAV), is a known member of the genus Gyrovirus and was first isolated from chickens in Japan in 1979. Some reports have also demonstrated that CAV can be identified in human stool specimens. In this study, a... more
    The chicken anemia virus (CAV), is a known member of the genus Gyrovirus and was first isolated from chickens in Japan in 1979. Some reports have also demonstrated that CAV can be identified in human stool specimens. In this study, a variant of CAV was detected using PCR with CAV-based primers in fecal samples of stray cats. The genome of CAV variant was sequenced and the results suggest that it could be a recombinant viral strain from parental CAV strains JQ690762 and AF311900. Recombination is an important evolutionary mechanism that contributes to genetic diversification. These findings indicate that CAV variant might have originated from CAV-infected chickens. The epidemiology and pathogenesis of this novel virus remains to be elucidated. This study underscores the importance of CAV surveillance and it presents the first evidence suggesting the possibility of CAV homologous recombination in cat.
    Bacillus tusciae Bonjour & Aragno 1994 is a hydrogen-oxidizing, thermoacidophilic spore former that lives as a facultative chemolithoautotroph in solfataras. Although 16S rRNA gene sequencing was well established at the time of the... more
    Bacillus tusciae Bonjour & Aragno 1994 is a hydrogen-oxidizing, thermoacidophilic spore former that lives as a facultative chemolithoautotroph in solfataras. Although 16S rRNA gene sequencing was well established at the time of the initial description of the organism, 16S sequence data were not available and the strain was placed into the genus Bacillus based on limited chemotaxonomic information. Despite the now obvious misplacement of strain T2 as a member of the genus Bacillus in 16S rRNA-based phylogenetic trees, the misclassification remained uncorrected for many years, which was likely due to the extremely difficult, analysis-hampering cultivation conditions and poor growth rate of the strain. Here we provide a taxonomic re-evaluation of strain T2T (= DSM 2912 = NBRC 15312) and propose its reclassification as the type strain of a new species, Kyrpidia tusciae, and the type species of the new genus Kyrpidia, which is a sister-group of Alicyclobacillus. The family Alicyclobacill...
    Gestational diabetes mellitus (GDM) is a frequent medical condition during pregnancy. Early diagnosis and treatment of GDM are crucial for both the mother and the baby. In the present study, we aimed to identify specific biomarkers to... more
    Gestational diabetes mellitus (GDM) is a frequent medical condition during pregnancy. Early diagnosis and treatment of GDM are crucial for both the mother and the baby. In the present study, we aimed to identify specific biomarkers to assist in the early detection of GDM and give some clues to the possible causes of GDM by comparing serum peptide profile differences between GDM patients and healthy controls. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was used in combination with weak cation exchange magnetic bead (WCX-MB). Levels of four peptides (4418.9, 2219.7, 2211.5, and 1533.4 Da) were significantly different. Interestingly, three of them (4418.9, 2211.5, and 1533.4 Da) were identified when GDM patients with two degrees of glucose intolerance were compared. Additionally, peptides 2211.5 and 1533.4 Da showed a decreasing trend as glucose intolerance increased, while peptide 4418.9 Da exhibited the reverse tendency. In conclusion, ...
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    Populus trees face constant challenges from the environment during their life cycle. To ensure their survival and reproduction, Populus trees deploy various types of defenses, one of which is the production of a myriad of secondary... more
    Populus trees face constant challenges from the environment during their life cycle. To ensure their survival and reproduction, Populus trees deploy various types of defenses, one of which is the production of a myriad of secondary metabolites. Compounds derived from the shikimate-phenylpropanoid pathway are the most abundant class of secondary metabolites synthesized in Populus. Among other major classes of secondary
    The present study investigated the dissipation behaviors of 4 typical personal care products (PCPs)-triclocarban (TCC), triclosan (TCS), tonalide (AHTN), and galaxolide (HHCB)- in soils amended with biosolids under field conditions in... more
    The present study investigated the dissipation behaviors of 4 typical personal care products (PCPs)-triclocarban (TCC), triclosan (TCS), tonalide (AHTN), and galaxolide (HHCB)- in soils amended with biosolids under field conditions in North China. The results showed that the 4 target compounds were detected in all biosolids-amended soils at levels of a few nanograms per gram to thousands of nanograms per gram (dry wt). The residual concentrations of the 4 PCPs were found in the following order: TCC > TCS > AHTN > HHCB. Significant dissipation of the 4 PCPs was observed in the biosolids-amended soils, with half-lives ranging from 26 d to 133 d. Furthermore, repeated biosolids applications and a higher biosolids application rate could lead to higher accumulation of the 4 PCPs in the agricultural soils. Based on the detected concentrations in the field trial and limited ecotoxicity data, high risks to soil organisms are expected for TCC, whereas low to medium risks are expecte...
    Keratocystic odontogenic tumors (KCOTs) are cystic epithelial neoplasms with a high recurrence rate. The molecular mechanisms underlying the initiation and progression of KCOTs are still largely unknown. Previous research showed that... more
    Keratocystic odontogenic tumors (KCOTs) are cystic epithelial neoplasms with a high recurrence rate. The molecular mechanisms underlying the initiation and progression of KCOTs are still largely unknown. Previous research showed that specific ablation of Smad4 in odontoblasts and dental epithelia resulted in spontaneous KCOTs in mice, and that constitutively activated Hedgehog (Hh) signaling was detected in the cyst epithelia of both Smad4(Co/Co) OC-Cre and Smad4(Co/Co) K5-Cre mice. Here, we ablated Smad4 in mouse odontoblasts and dental epithelia and compared the sizes and numbers of KCOTs. Both the number and size of KCOTs in Smad4(Co/Co) OC-Cre mice were larger than those in Smad4(Co/Co) K5-Cre mice, suggesting that paracrine signals from root odontoblasts play a more important role than those from Hertwig's epithelial root sheath (HERS) cells. Copyright © 2015. Published by Elsevier Inc.
    Objective: To investigate the differential salivary protein expression profiles between children with severe early childhood caries (S-ECC) and caries-free (CF) children at the age of 3 years. Methods: We used matrix-assisted laser... more
    Objective: To investigate the differential salivary protein expression profiles between children with severe early childhood caries (S-ECC) and caries-free (CF) children at the age of 3 years. Methods: We used matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) combined with weak cation exchange magnetic beads, and peptide mass fingerprints were created by scanning mass spectrometry signals. Salivary samples from 20 children were analyzed (10 for each group). Results: Eleven protein peaks were significantly different (p < 0.05) between the two groups. Eight of these peaks were higher in the S-ECC group and three were higher in the CF group. To establish a diagnostic model for discrimination between the two groups, we chose three peptides (3,186.2, 3,195.8 and 3,324.8 Da) that exhibited the best fitted curve, by which the two groups were better separated when compared with other combinations. Conclusions: The salivary biomarkers identified r...
    Functional evaluation of potentially damaged lungs donated after cardiac death is crucial for widespread clinical transplantation. To date, the mean weight of animals used in studies of ex vivo lung perfusion (EVLP) has been 60 kg;... more
    Functional evaluation of potentially damaged lungs donated after cardiac death is crucial for widespread clinical transplantation. To date, the mean weight of animals used in studies of ex vivo lung perfusion (EVLP) has been 60 kg; however, in the clinical setting, donor weight may be greater. To investigate EVLP using lungs from large pigs (mean weight, 115 kg) to simulate human adult lungs donated after cardiac death. Five heart-lung blocks were obtained at 20 minutes after death at the slaughterhouse. The lungs were flushed and preserved on ice for 6 hours before being connected to an ex vivo lung circuit, and were perfused for at least 2 hours. In all cases, perfusion was sustained for at least 2 hours. Mean (SEM) final flow rate was 4.9 (0.1) L/min, pulmonary artery pressure was 14.8 (1.7) mm Hg, and oxygen tension/fraction of inspired oxygen was 518.0 (18.0) mm Hg. The shunt fraction was 20.5% (4.0%). Histologic analysis demonstrated no significant pulmonary edema at the end of perfusion. We successfully completed EVLP using lungs from large pigs.
    It has been widely demonstrated that the hedgehog pathway is strongly associated with basal cell carcinoma of the skin (NBCCS). To assess potential DNA alterations related to keratocystic odontogenic tumors (KCOTs), we sequenced... more
    It has been widely demonstrated that the hedgehog pathway is strongly associated with basal cell carcinoma of the skin (NBCCS). To assess potential DNA alterations related to keratocystic odontogenic tumors (KCOTs), we sequenced smoothened (SMO) genes in 12 sporadic KCOTs.
    Neural epidermal growth factor-like (NEL)-like protein 1 (NELL-1) has been identified as an osteoinductive differentiation factor that promotes mesenchymal stem cell (MSC) osteogenic differentiation. In addition to full-length NELL-1,... more
    Neural epidermal growth factor-like (NEL)-like protein 1 (NELL-1) has been identified as an osteoinductive differentiation factor that promotes mesenchymal stem cell (MSC) osteogenic differentiation. In addition to full-length NELL-1, there are several NELL-1-related transcripts reported. We used rapid amplification of cDNA ends (RACE) to recover potential cDNA of NELL-1 isoforms. A NELL-1 isoform with the N-terminal 240 amino acid (aa) residues truncated was identified. While full-length NELL-1 that contains 810 aa residues (NELL-1810) plays an important role in embryologic skeletal development, the N-terminal-truncated NELL-1 isoform (NELL-1570) was expressed post-natally. Similar to NELL-1810, NELL-1570 induced MSC osteogenic differentiation. In addition, NELL-1570 significantly stimulated MSC proliferation in multiple MSC-like populations such as murine C3H10T1/2 MSC cell line, mouse primary MSCs, and perivascular stem cells (PSCs), which is a type of stem cells proposed as the ...
    Objective: To detect changes in the microbial richness of dental plaque and oral behaviors during caries development in young Chinese children. Methods: Supragingival plaque samples and a survey of oral behaviors of 130 children aged 3 at... more
    Objective: To detect changes in the microbial richness of dental plaque and oral behaviors during caries development in young Chinese children. Methods: Supragingival plaque samples and a survey of oral behaviors of 130 children aged 3 at baseline were analyzed at 6 months and 12 months. Total DNA was isolated from all samples and PCR-denaturing gradient gel electrophoresis analysis was conducted. Results: In the follow-up, 44 children had caries or cavity fillings at 6 months, a further 28 children had caries or cavity fillings at 12 months. The other 58 children remained caries-free at 12 months. According to the changes in caries status at the 12-month follow-up, all participants were divided into three groups: caries-free, caries at 6 months and caries at 12 months. The changes in oral behaviors during the 12-month follow-up were not significantly different in the three groups. The frequency of eating sweets and eating sweets before sleeping was significantly different among the...
    To clarify the effects of the association between combined oral contraceptives (COC) use and ACE/AGT gene on stroke risk, and to undertake a preliminarily study of the molecular mechanism of the association between COC exposure and... more
    To clarify the effects of the association between combined oral contraceptives (COC) use and ACE/AGT gene on stroke risk, and to undertake a preliminarily study of the molecular mechanism of the association between COC exposure and predisposing genes of hypertension on the increased risk of stroke. This study was a multi-center case-control study based on the population of 25 towns in the surveillance regions of Jiangsu province, China. (i) The univariate analysis of the frequency of the DD genotype of ACE insert/delete (I/D) polymorphism between the cases and controls indicated its significant association with the stroke (P<0.01), especially for hemorrhagic stroke (P<0.01). (ii) Women with COC exposure and ACE I/D genotype had an increased risk for all strokes [adjusted odds ratio 5.63; 95% confidence interval (CI), 2.20, 15.68], and an increased risk for hemorrhagic stroke (adjusted odds ratio 31.53; 95% CI, 3.54, 281.14) after adjustment for education and occupation. (iii) Multivariate analyses showed that hypertension was the most important risk factor for hemorrhagic stroke and ischemic stroke. COC use was a significant risk factor for hemorrhagic stroke. The combined effects of COC use, for 15 years and above, and ACE I/D polymorphism increased the risk of all strokes by more than eight times, and the risk of hemorrhagic stroke by more than 15 times. Hypertension was a most important risk factor for stroke incidence. The D allele of ACE I/D polymorphism may be a potential risk allele for stroke. COC users carried the ID+DD genotype that may further increase the risk of stroke, especially for hemorrhagic stroke.
    Gestational diabetes mellitus (GDM) is a frequent medical condition during pregnancy. Early diagnosis and treatment of GDM are crucial for both the mother and the baby. In the present study, we aimed to identify specific biomarkers to... more
    Gestational diabetes mellitus (GDM) is a frequent medical condition during pregnancy. Early diagnosis and treatment of GDM are crucial for both the mother and the baby. In the present study, we aimed to identify specific biomarkers to assist in the early detection of GDM and give some clues to the possible causes of GDM by comparing serum peptide profile differences between GDM patients and healthy controls. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was used in combination with weak cation exchange magnetic bead (WCX-MB). Levels of four peptides (4418.9, 2219.7, 2211.5, and 1533.4 Da) were significantly different. Interestingly, three of them (4418.9, 2211.5, and 1533.4 Da) were identified when GDM patients with two degrees of glucose intolerance were compared. Additionally, peptides 2211.5 and 1533.4 Da showed a decreasing trend as glucose intolerance increased, while peptide 4418.9 Da exhibited the reverse tendency. In conclusion, ...
    Mass spectrometry (MS) enables rapid and sensitive qualitative and quantitative analyses of biomolecules (proteins, peptides, oligosaccharides, lipids, DNA, and RNA), drugs, and metabolites. MS has become an essential tool in modern... more
    Mass spectrometry (MS) enables rapid and sensitive qualitative and quantitative analyses of biomolecules (proteins, peptides, oligosaccharides, lipids, DNA, and RNA), drugs, and metabolites. MS has become an essential tool in modern biomedical research, including the analysis of DNA methylation. DNA methylation has been reported in many cancers, suggesting that it can be utilized as an early biomarker to improve the early diagnosis rate. Using matrix-assisted laser desorption/ionization time-of-flight MS and MassCLEAVE reagent, we compared Nell-1 hypermethylation levels among tumor tissues, paracarcinoma tissues, and normal tissues from gastric cancer patients. Almost 80% of the CpG sites in the amplicons produced were covered by the analysis. Our results indicate a significant difference in methylation status between gastric cancer tissue (a higher level) and normal tissue. The same trend was identified in gastric cancer tissue versus paracarcinoma tissue. We also detected lower relative expression of Nell-1 by real-time PCR. Furthermore, immunohistochemical analyses revealed that Nell-1 staining was less intense in cancer tissue relative to normal tissue and that the tumor cells had spread to the muscle layer. These findings may serve as a guide for the early diagnosis of gastric cancer.
    The key properties of microalgal biodiesel are largely determined by the composition of its fatty acid methyl esters (FAMEs). The gas chromatography (GC) based techniques for fatty acid analysis involve energy-intensive and time-consuming... more
    The key properties of microalgal biodiesel are largely determined by the composition of its fatty acid methyl esters (FAMEs). The gas chromatography (GC) based techniques for fatty acid analysis involve energy-intensive and time-consuming procedures and thus are less suitable for high-throughput screening applications. In the present study, a novel quantification method for microalgal fatty acids was established based on the near-infrared spectroscopy (NIRS) technique. The lyophilized cells of oleaginous Chlorella containing different contents of lipids were scanned by NIRS and their fatty acid profiles were determined by GC-MS. NIRS models were developed based on the chemometric correlation of the near-infrared spectra with fatty acid profiles in algal biomass. The optimized NIRS models showed excellent performances for predicting the contents of total fatty acids, C16:0, C18:0, C18:1 and C18:3, with the coefficient of determination (R2) being 0.998, 0.997, 0.989, 0.991 and 0.997, ...
    Fusarium contamination is considered a major agricultural problem, which could not only significantly reduce yield and quality of agricultural products, but produce mycotoxins that are virulence factors responsible for many diseases of... more
    Fusarium contamination is considered a major agricultural problem, which could not only significantly reduce yield and quality of agricultural products, but produce mycotoxins that are virulence factors responsible for many diseases of humans and farm animals. One strategy to identify toxigenic Fusarium species is the use of modern molecular methods, which include the analysis of DNA target regions for differentiation of the Fusarium species, particularly the mycotoxin-producing Fusarium species such as F. verticillioides and F. graminearum. Additionally, polymerase chain reaction assays are used to determine the genes involved in the biosynthesis of the toxins in order to facilitate a qualitative and quantitative detection of Fusarium-producing mycotoxins. Also, it is worth mentioning that some factors that modulate the biosynthesis of mycotoxins are not only determined by their biosynthetic gene clusters, but also by environmental conditions. Therefore, all of the aforementioned f...
    Water-dispersible CaF2 and Yb(3+)/Er(3+) codoped CaF2 (CaF2:Yb(3+)/Er(3+)) nanocrystals with different sizes and different Yb(3+) and Er(3+) dopant concentrations were synthesized using ionic liquid 1-n-butyl-3-methyl imidazolium... more
    Water-dispersible CaF2 and Yb(3+)/Er(3+) codoped CaF2 (CaF2:Yb(3+)/Er(3+)) nanocrystals with different sizes and different Yb(3+) and Er(3+) dopant concentrations were synthesized using ionic liquid 1-n-butyl-3-methyl imidazolium tetrafluoroborate as a fluorine source by the rapid microwave-assisted solvothermal method. It was found that the morphology, size and crystallinity of CaF2:Yb(3+)/Er(3+) nanocrystals could be adjusted by using adenosine 5'-triphosphate disodium salt (ATP). Yb(3+) and Er(3+) ions were doped into CaF2 nanocrystals to enable upconversion luminescence emission, and the as-prepared CaF2:Yb(3+)/Er(3+) samples exhibited upconversion luminescence upon excitation at 980 nm. Confocal laser scanning microscopy images showed that the CaF2:Yb(3+)/Er(3+) nanocrystals could be used for efficient labeling of human gastric carcinoma cells. Moreover, in vitro cytotoxicity experiments indicated that the as-prepared CaF2:Yb(3+)/Er(3+) nanocrystals had essentially little c...
    Amorphous calcium phosphate (ACP) microspheres with a porous and hollow structure have been prepared using an aqueous solution containing CaCl2 as a calcium source, adenosine triphosphate disodium salt (Na2ATP) as a phosphorus source in... more
    Amorphous calcium phosphate (ACP) microspheres with a porous and hollow structure have been prepared using an aqueous solution containing CaCl2 as a calcium source, adenosine triphosphate disodium salt (Na2ATP) as a phosphorus source in the presence of a block copolymer methoxyl poly(ethylene glycol)-block-poly(d,l-lactide) (mPEG-PLA) by the microwave-assisted hydrothermal method. The effects of microwave hydrothermal temperature and the concentrations of CaCl2 and Na2ATP on the crystal phase and morphology of the product are investigated. The as-prepared ACP porous hollow microspheres have a relatively high specific surface area of 232.9m(2)g(-1) and an average pore size of 9.9nm. A typical anticancer drug, docetaxel, is used to evaluate the drug loading ability and drug release behavior of ACP porous hollow microspheres in phosphate buffered saline (PBS) with different pH values of 4.5 and 7.4. The experiments reveal that the ACP porous hollow microspheres have a high drug loading...
    To achieve the accurate diagnosis and efficient in situ therapy of malignant tumors is encouraging but still remains a big challenge. The integration of upconversion nanoparticles and mesoporous silica that can combine the... more
    To achieve the accurate diagnosis and efficient in situ therapy of malignant tumors is encouraging but still remains a big challenge. The integration of upconversion nanoparticles and mesoporous silica that can combine the diagnostic/therapeutic functions within a single platform, may provide a more advanced way for the efficient theranostics of cancer. In this study, sub-80 nm rattle-structured multifunctional Gd-UCNPs core/mesoporous silica shell nanotheranostics (UCMSNs) were successfully constructed for the co-delivery of a radio-/photo-sensitizer hematoporphyrin (HP) and a radiosensitizer/chemodrug docetaxel (Dtxl). Upon NIR excitation and X-ray irradiation, the complete tumor elimination has been achieved by the synergetic chemo-/radio-/photodynamic tri-modal therapy under the assistance of simultaneous magnetic/upconversion luminescent (MR/UCL) bimodal imaging. To the best of our knowledge, this study is the first example of achieving tri-modal synergetic therapy in one singl...

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