The anterior cervical vertebrae form the skeletal connection between the cranial and postcranial ... more The anterior cervical vertebrae form the skeletal connection between the cranial and postcranial skeletons in higher tetrapods. As a result, the morphology of the atlas-axis complex is likely to be shaped by selection pressures acting on either the head or neck. The neoceratopsian (Reptilia:Dinosauria) syncervical represents one of the most highly modified atlas-axis regions in vertebrates, being formed by the complete coalescence of the three most anterior cervical vertebrae. In ceratopsids, the syncervical has been hypothesized to be an adaptation to support a massive skull, or to act as a buttress during intraspecific head-to-head combat. Here we test these functional/adaptive hypotheses within a phylogenetic framework, and critically examine the previously proposed methods for quantifying relative head size in the fossil record for the first time. Results indicate that neither the evolution of cranial weaponry nor large head size correlates with the origin of cervical fusion in ceratopsians, and we, therefore, reject both adaptive hypotheses for the origin of the syncervical. Anterior cervical fusion has evolved independently in a number of amniote clades, and further research on extant groups with this peculiar anatomy is needed to understand the evolutionary basis for cervical fusion in Neoceratopsia. This article is protected by copyright. All rights reserved.
Spectacularly preserved non-avian dinosaurs with integumentary filaments/feathers have revolution... more Spectacularly preserved non-avian dinosaurs with integumentary filaments/feathers have revolutionized dinosaur studies and fostered the suggestion that the dinosaur common ancestor possessed complex integumentary structures homologous to feathers. This hypothesis has major implications for interpreting dinosaur biology, but has not been tested rigorously. Using a comprehensive database of dinosaur skin traces, we apply maximum-likelihood methods to reconstruct the phylogenetic distribution of epidermal structures and interpret their evolutionary history. Most of these analyses find no compelling evidence for the appearance of protofeathers in the dinosaur common ancestor and scales are usually recovered as the plesiomorphic state, but results are sensitive to the outgroup condition in pterosaurs. Rare occurrences of ornithischian filamentous integument might represent independent acquisitions of novel epidermal structures that are not homologous with theropod feathers.
World journal of gastrointestinal endoscopy, Jan 16, 2015
The intentional ingestion of foreign objects (IIFO) is described more commonly in prison populati... more The intentional ingestion of foreign objects (IIFO) is described more commonly in prison populations than in the general population, with an estimated annual incidence of 1 in 1900 inmates in our state correctional facilities. Incidents often involve ingestion of small metal objects (e.g., paperclips, razor blades) or other commonly available items like pens or eating utensils. Despite ingestion of relatively sharp objects, most episodes can be clinically managed with either observation or endoscopy. Surgery should be reserved for those with signs or symptoms of gastrointestinal perforation or obstruction. For those with a history of IIFO, efforts should focus on prevention of recurrence as subsequent episodes are associated with higher morbidity, significant healthcare and security costs. The pattern of IIFO is often repetitive, with escalation both in frequency of ingestions and in number of items ingested. Little is known about successful prevention strategies, but efforts to mon...
The well-sampled Late Cretaceous fossil record of North America remains the only high-resolution ... more The well-sampled Late Cretaceous fossil record of North America remains the only high-resolution dataset for evaluating patterns of dinosaur diversity leading up to the terminal Cretaceous extinction event. Hadrosaurine hadrosaurids (Dinosauria: Ornithopoda) closely related to Edmontosaurus are among the most common megaherbivores in latest Campanian and Maastrichtian deposits of western North America. However, interpretations of edmontosaur species richness and biostratigraphy
Non-avian dinosaurs went extinct 66 million years ago, geologically coincident with the impact of... more Non-avian dinosaurs went extinct 66 million years ago, geologically coincident with the impact of a large bolide (comet or asteroid) during an interval of massive volcanic eruptions and changes in temperature and sea level. There has long been fervent debate about how these events affected dinosaurs. We review a wealth of new data accumulated over the past two decades, provide updated and novel analyses of long-term dinosaur diversity trends during the latest Cretaceous, and discuss an emerging consensus on the extinction’s tempo and causes. Little support exists for a global, long-term decline across non-avian dinosaur diversity prior to their extinction at the end of the Cretaceous. However, restructuring of latest Cretaceous dinosaur faunas in North America led to reduced diversity of large-bodied herbivores, perhaps making communities more susceptible to cascading extinctions. The abruptness of the dinosaur extinction suggests a key role for the bolide
Unintentionally retained items feature prominently among surgical "never events." Our k... more Unintentionally retained items feature prominently among surgical "never events." Our knowledge of these rare occurrences, including natural history and intraoperative safety omission or variance (SOV) profile, is limited. We sought to bridge existing knowledge gaps by presenting a secondary analysis of a multicenter study focused on these important aspects of retained surgical items (RSIs). This is a post hoc analysis of results from a multicenter retrospective study of RSIs between January 2003 and December 2009. After excluding previously reported intravascular RSIs (n = 13), a total of 71 occurrences were analyzed for (1) item location and type; (2) time to presentation and/or discovery; (3) presenting signs and symptoms; (4) procedure and incision characteristics; (5) pathology reports; and (6) patterns of SOVs abstracted from medical and operative records. These SOV were then grouped into individual vs team errors and single- vs multifactorial occurrences. Among 71 c...
The open abdominal (OA) approach is a management strategy used in the most severely injured traum... more The open abdominal (OA) approach is a management strategy used in the most severely injured trauma patients. In addition to the morbidity and mortality, a major challenge is the gradual development of dense adhesions that make reoperations progressively more difficult. This randomized, prospective, proof-of-concept study was conducted to determine the effect of carboxymethylcellulose sodium hyaluronate adhesion barrier (CMHAB; Seprafilm, Genzyme Biosurgery, Bridgewater, NJ) on abdominal adhesions and wound characteristics in trauma open abdomens. A prospective, randomized, controlled study of wound and adhesion characteristics with or without CMHAB was conducted at 5 level I trauma centers. Consenting patients were randomized to either CMHAB or no adhesion barrier (NAB) groups. We evaluated patient demographics, injury characteristics/severity, reason for OA management, wound sizes (transverse/longitudinal), Zuhlke adhesion score, abdominal contamination score, hospital/intensive ca...
Drug metabolism and disposition: the biological fate of chemicals, 2015
The metabolic fate of adrenocorticotropic hormone (ACTH) fragment 4-10 (4-10) was evaluated follo... more The metabolic fate of adrenocorticotropic hormone (ACTH) fragment 4-10 (4-10) was evaluated following incorporation of a nonradioactive (127)I-tag and with selective detection of I(+) at m/z 127 by inductively coupled plasma mass spectrometry (ICP-MS). (127)I has all the advantages of radioactive (125)I as a metabolite tracer and, together with its detection in the femtogram range, has led to a successful metabolite profiling of (127)I-ACTH (4-10) in vitro. The observed metabolic stability of this peptide in tissue preparations from human was plasma > kidney S9…
Clearance of cervical spine injury (CSI) in the obtunded or comatose blunt trauma patient remains... more Clearance of cervical spine injury (CSI) in the obtunded or comatose blunt trauma patient remains controversial. In patients with unreliable physical examination and no evidence of CSI on computed tomography (CT), magnetic resonance imaging of the cervical spine (CS-MRI) is the typical follow-up study. There is a growing body of evidence suggesting that CS-MRI is unnecessary with negative findings on a multi-detector CT (MDCT) scan. This review article systematically analyzes current literature to address the controversies surrounding clearance of CSI in obtunded blunt trauma patients. A literature search through MEDLINE database was conducted using all databases on the National Center for Biotechnology Information (NCBI) website (www.ncbi.nlm.nih.gov) for keywords: "cervical spine injury,"…
Trauma dogma dictates that the physiologic response to injury is blunted by beta-blockers and oth... more Trauma dogma dictates that the physiologic response to injury is blunted by beta-blockers and other cardiac medications. We sought to determine how the pre-injury cardiac medication profile influences admission physiology and post-injury outcomes. Trauma patients older than 45 evaluated at our center were retrospectively studied. Pre-injury medication profiles were evaluated for angiotensin-converting enzyme inhibitors / angiotensin receptor blockers (ACE-I/ARB), beta-blockers, calcium channel blockers, amiodarone, or a combination of the above mentioned agents. Multivariable logistic regression or linear regression analyses were used to identify relationships between pre-injury medications, vital signs on presentation, post-injury complications, length of hospital stay, and mortality. Records of 645 patients were reviewed (mean age 62.9 years, Injury Severity Score >10, 23%). Our analysis demonstrated no effect on systolic and diastolic blood pressures from beta-blocker, ACE-I/A...
Canadian journal of surgery. Journal canadien de chirurgie, 2014
Many trauma survivors face challenges of impaired functioning, limited activities and reduced par... more Many trauma survivors face challenges of impaired functioning, limited activities and reduced participation. Recovery from injury after acute care, therefore, becomes an important public health issue. This commentary discusses a framework for evaluating outcomes of acute care.
Inferior vena cava collapsibility index (IVC-CI) has been shown to correlate with both clinical a... more Inferior vena cava collapsibility index (IVC-CI) has been shown to correlate with both clinical and invasive assessment of intravascular volume status, but has important limitations such as the requirement for advanced sonographic skills, the degree of difficulty in obtaining those skills, and often challenging visualization of the IVC in the postoperative patient. The current study aims to explore the potential for using femoral (FV) or internal jugular (IJV) vein collapsibility as alternative sonographic options in the absence of adequate IVC visualization. A prospective, observational study comparing IVC-CI and Fem- and/or IJV-CI was performed in two intensive care units (ICU) between January 2012 and April 2014. Concurrent M-mode measurements of IVC-CI and FV- and/or IJV-CI were collected during each sonographic session. Measurements of IVC were obtained using standard technique. IJV-CI and FV-CI were measured using high-frequency, linear array ultrasound probe placed in the cor...
The relevance of new-onset atrial fibrillation (AF) after esophagectomy remains poorly defined. T... more The relevance of new-onset atrial fibrillation (AF) after esophagectomy remains poorly defined. This study's primary goal is to better define the incidence, clinical patterns, and outcomes associated with the development of AF after esophagectomy. The study is a retrospective review of patients undergoing esophagectomy at a single academic center between May 1996 and December 2007. Patients with new-onset AF were evaluated by univariate and multivariate analyses for risk factors associated with AF onset and outcomes. New-onset AF was noted in 32 of 156 (20.5%) patients after esophagectomy. Most (16/32, 50%) developed AF within 48 h, and 28 of 32 (87.5%) developed new AF within 72 h of surgery. Pulmonary complications were more frequent in patients with AF than those without AF (59.4% vs. 15.3%, P < 0.01) and usually immediately preceded or occurred concurrently with AF. Anastomotic leaks were significantly more common in patients with AF than those without (28.1% vs. 6.45%, P…
International journal of critical illness and injury science, 2011
One of the hallmarks of modern medicine is the improving management of chronic health conditions.... more One of the hallmarks of modern medicine is the improving management of chronic health conditions. Long-term control of chronic disease entails increasing utilization of multiple medications and resultant polypharmacy. The goal of this study is to improve our understanding of the impact of polypharmacy on outcomes in trauma patients 45 years and older. Patients of age ≥45 years were identified from a Level I trauma center institutional registry. Detailed review of patient records included the following variables: Home medications, comorbid conditions, injury severity score (ISS), Glasgow coma scale (GCS), morbidity, mortality, hospital length of stay (LOS), intensive care unit (ICU) LOS, functional outcome measures (FOM), and discharge destination. Polypharmacy was defined by the number of medications: 0-4 (minor), 5-9 (major), or ≥10 (severe). Age- and ISS-adjusted analysis of variance and multivariate analyses were performed for these groups. Comorbidity-polypharmacy score (CPS) wa...
The polymorphonuclear neutrophil (PMN) has been implicated in the pathogenesis of endothelial cel... more The polymorphonuclear neutrophil (PMN) has been implicated in the pathogenesis of endothelial cell (EC) damage and organ injury following hemorrhagic shock. Pentastarch (PTS), a low substituted medium molecular weight (MW) colloid, improves hemodynamics in hypovolemic shock and cardiac surgery. No data exist comparing the immunomodulation of PTS and Ringer&#39;s lactate (RL) on the activation of PMN in hemorrhagic shock in vivo. Using an in vivo murine hemorrhagic shock model (blood withdrawal to maintain 50 mmHg x 45 min), circulating PMN were observed every 15 minutes using intravital microscopy on cremaster muscle. EC-PMN interactions (videorecorded and subsequently analyzed blindly), vessel leakage (live epifluorescence after injection of 50 mg/kg fluorescent albumin) and PMN expression of L-selectin (immunofluorescent monoclonal antibodies and flow cytometry) were evaluated in three resuscitation groups: PTS (7.14 mL/kg 10% pentastarch/0.9% NaCl + shed blood, n = 13), RL (RL [2 x shed blood volume] + shed blood, n = 13) and SHAM (0 hemorrhage, 0 resuscitation, n = 9). Significance was evaluated by ANOVA with Bonferroni correction. PMN rolling was significantly diminished in PTS and SHAM as compared to RL animals at all time points. Similar differences were found in PMN adherence to EC at most time points onwards from 15 minutes following resuscitation. In vivo vessel permeability was lowest in SHAM and PTS animals (mean 0.274 +/- 0.07 and 0.356 +/- 0.15, respectively, p &gt; 0.05) and highest in RL animals (0.667 +/- 0.09, p &lt; 0.001 vs PTS or SHAM). PMN L-selectin expression tended to be higher in the RL group than either SHAM and PTS groups. There were no flow-mechanics differences between groups (vessel diameter, mean red cell velocity, shear stress, shear rate). 10% pentastarch reduces RL-associated EC-PMN interactions and vessel leakage following hemorrhagic shock. These results support the use of low MW starches to resuscitate hemorrhagic shock, potentially reducing PMN-mediated tissue injury.
The anterior cervical vertebrae form the skeletal connection between the cranial and postcranial ... more The anterior cervical vertebrae form the skeletal connection between the cranial and postcranial skeletons in higher tetrapods. As a result, the morphology of the atlas-axis complex is likely to be shaped by selection pressures acting on either the head or neck. The neoceratopsian (Reptilia:Dinosauria) syncervical represents one of the most highly modified atlas-axis regions in vertebrates, being formed by the complete coalescence of the three most anterior cervical vertebrae. In ceratopsids, the syncervical has been hypothesized to be an adaptation to support a massive skull, or to act as a buttress during intraspecific head-to-head combat. Here we test these functional/adaptive hypotheses within a phylogenetic framework, and critically examine the previously proposed methods for quantifying relative head size in the fossil record for the first time. Results indicate that neither the evolution of cranial weaponry nor large head size correlates with the origin of cervical fusion in ceratopsians, and we, therefore, reject both adaptive hypotheses for the origin of the syncervical. Anterior cervical fusion has evolved independently in a number of amniote clades, and further research on extant groups with this peculiar anatomy is needed to understand the evolutionary basis for cervical fusion in Neoceratopsia. This article is protected by copyright. All rights reserved.
Spectacularly preserved non-avian dinosaurs with integumentary filaments/feathers have revolution... more Spectacularly preserved non-avian dinosaurs with integumentary filaments/feathers have revolutionized dinosaur studies and fostered the suggestion that the dinosaur common ancestor possessed complex integumentary structures homologous to feathers. This hypothesis has major implications for interpreting dinosaur biology, but has not been tested rigorously. Using a comprehensive database of dinosaur skin traces, we apply maximum-likelihood methods to reconstruct the phylogenetic distribution of epidermal structures and interpret their evolutionary history. Most of these analyses find no compelling evidence for the appearance of protofeathers in the dinosaur common ancestor and scales are usually recovered as the plesiomorphic state, but results are sensitive to the outgroup condition in pterosaurs. Rare occurrences of ornithischian filamentous integument might represent independent acquisitions of novel epidermal structures that are not homologous with theropod feathers.
World journal of gastrointestinal endoscopy, Jan 16, 2015
The intentional ingestion of foreign objects (IIFO) is described more commonly in prison populati... more The intentional ingestion of foreign objects (IIFO) is described more commonly in prison populations than in the general population, with an estimated annual incidence of 1 in 1900 inmates in our state correctional facilities. Incidents often involve ingestion of small metal objects (e.g., paperclips, razor blades) or other commonly available items like pens or eating utensils. Despite ingestion of relatively sharp objects, most episodes can be clinically managed with either observation or endoscopy. Surgery should be reserved for those with signs or symptoms of gastrointestinal perforation or obstruction. For those with a history of IIFO, efforts should focus on prevention of recurrence as subsequent episodes are associated with higher morbidity, significant healthcare and security costs. The pattern of IIFO is often repetitive, with escalation both in frequency of ingestions and in number of items ingested. Little is known about successful prevention strategies, but efforts to mon...
The well-sampled Late Cretaceous fossil record of North America remains the only high-resolution ... more The well-sampled Late Cretaceous fossil record of North America remains the only high-resolution dataset for evaluating patterns of dinosaur diversity leading up to the terminal Cretaceous extinction event. Hadrosaurine hadrosaurids (Dinosauria: Ornithopoda) closely related to Edmontosaurus are among the most common megaherbivores in latest Campanian and Maastrichtian deposits of western North America. However, interpretations of edmontosaur species richness and biostratigraphy
Non-avian dinosaurs went extinct 66 million years ago, geologically coincident with the impact of... more Non-avian dinosaurs went extinct 66 million years ago, geologically coincident with the impact of a large bolide (comet or asteroid) during an interval of massive volcanic eruptions and changes in temperature and sea level. There has long been fervent debate about how these events affected dinosaurs. We review a wealth of new data accumulated over the past two decades, provide updated and novel analyses of long-term dinosaur diversity trends during the latest Cretaceous, and discuss an emerging consensus on the extinction’s tempo and causes. Little support exists for a global, long-term decline across non-avian dinosaur diversity prior to their extinction at the end of the Cretaceous. However, restructuring of latest Cretaceous dinosaur faunas in North America led to reduced diversity of large-bodied herbivores, perhaps making communities more susceptible to cascading extinctions. The abruptness of the dinosaur extinction suggests a key role for the bolide
Unintentionally retained items feature prominently among surgical "never events." Our k... more Unintentionally retained items feature prominently among surgical "never events." Our knowledge of these rare occurrences, including natural history and intraoperative safety omission or variance (SOV) profile, is limited. We sought to bridge existing knowledge gaps by presenting a secondary analysis of a multicenter study focused on these important aspects of retained surgical items (RSIs). This is a post hoc analysis of results from a multicenter retrospective study of RSIs between January 2003 and December 2009. After excluding previously reported intravascular RSIs (n = 13), a total of 71 occurrences were analyzed for (1) item location and type; (2) time to presentation and/or discovery; (3) presenting signs and symptoms; (4) procedure and incision characteristics; (5) pathology reports; and (6) patterns of SOVs abstracted from medical and operative records. These SOV were then grouped into individual vs team errors and single- vs multifactorial occurrences. Among 71 c...
The open abdominal (OA) approach is a management strategy used in the most severely injured traum... more The open abdominal (OA) approach is a management strategy used in the most severely injured trauma patients. In addition to the morbidity and mortality, a major challenge is the gradual development of dense adhesions that make reoperations progressively more difficult. This randomized, prospective, proof-of-concept study was conducted to determine the effect of carboxymethylcellulose sodium hyaluronate adhesion barrier (CMHAB; Seprafilm, Genzyme Biosurgery, Bridgewater, NJ) on abdominal adhesions and wound characteristics in trauma open abdomens. A prospective, randomized, controlled study of wound and adhesion characteristics with or without CMHAB was conducted at 5 level I trauma centers. Consenting patients were randomized to either CMHAB or no adhesion barrier (NAB) groups. We evaluated patient demographics, injury characteristics/severity, reason for OA management, wound sizes (transverse/longitudinal), Zuhlke adhesion score, abdominal contamination score, hospital/intensive ca...
Drug metabolism and disposition: the biological fate of chemicals, 2015
The metabolic fate of adrenocorticotropic hormone (ACTH) fragment 4-10 (4-10) was evaluated follo... more The metabolic fate of adrenocorticotropic hormone (ACTH) fragment 4-10 (4-10) was evaluated following incorporation of a nonradioactive (127)I-tag and with selective detection of I(+) at m/z 127 by inductively coupled plasma mass spectrometry (ICP-MS). (127)I has all the advantages of radioactive (125)I as a metabolite tracer and, together with its detection in the femtogram range, has led to a successful metabolite profiling of (127)I-ACTH (4-10) in vitro. The observed metabolic stability of this peptide in tissue preparations from human was plasma > kidney S9…
Clearance of cervical spine injury (CSI) in the obtunded or comatose blunt trauma patient remains... more Clearance of cervical spine injury (CSI) in the obtunded or comatose blunt trauma patient remains controversial. In patients with unreliable physical examination and no evidence of CSI on computed tomography (CT), magnetic resonance imaging of the cervical spine (CS-MRI) is the typical follow-up study. There is a growing body of evidence suggesting that CS-MRI is unnecessary with negative findings on a multi-detector CT (MDCT) scan. This review article systematically analyzes current literature to address the controversies surrounding clearance of CSI in obtunded blunt trauma patients. A literature search through MEDLINE database was conducted using all databases on the National Center for Biotechnology Information (NCBI) website (www.ncbi.nlm.nih.gov) for keywords: "cervical spine injury,"…
Trauma dogma dictates that the physiologic response to injury is blunted by beta-blockers and oth... more Trauma dogma dictates that the physiologic response to injury is blunted by beta-blockers and other cardiac medications. We sought to determine how the pre-injury cardiac medication profile influences admission physiology and post-injury outcomes. Trauma patients older than 45 evaluated at our center were retrospectively studied. Pre-injury medication profiles were evaluated for angiotensin-converting enzyme inhibitors / angiotensin receptor blockers (ACE-I/ARB), beta-blockers, calcium channel blockers, amiodarone, or a combination of the above mentioned agents. Multivariable logistic regression or linear regression analyses were used to identify relationships between pre-injury medications, vital signs on presentation, post-injury complications, length of hospital stay, and mortality. Records of 645 patients were reviewed (mean age 62.9 years, Injury Severity Score >10, 23%). Our analysis demonstrated no effect on systolic and diastolic blood pressures from beta-blocker, ACE-I/A...
Canadian journal of surgery. Journal canadien de chirurgie, 2014
Many trauma survivors face challenges of impaired functioning, limited activities and reduced par... more Many trauma survivors face challenges of impaired functioning, limited activities and reduced participation. Recovery from injury after acute care, therefore, becomes an important public health issue. This commentary discusses a framework for evaluating outcomes of acute care.
Inferior vena cava collapsibility index (IVC-CI) has been shown to correlate with both clinical a... more Inferior vena cava collapsibility index (IVC-CI) has been shown to correlate with both clinical and invasive assessment of intravascular volume status, but has important limitations such as the requirement for advanced sonographic skills, the degree of difficulty in obtaining those skills, and often challenging visualization of the IVC in the postoperative patient. The current study aims to explore the potential for using femoral (FV) or internal jugular (IJV) vein collapsibility as alternative sonographic options in the absence of adequate IVC visualization. A prospective, observational study comparing IVC-CI and Fem- and/or IJV-CI was performed in two intensive care units (ICU) between January 2012 and April 2014. Concurrent M-mode measurements of IVC-CI and FV- and/or IJV-CI were collected during each sonographic session. Measurements of IVC were obtained using standard technique. IJV-CI and FV-CI were measured using high-frequency, linear array ultrasound probe placed in the cor...
The relevance of new-onset atrial fibrillation (AF) after esophagectomy remains poorly defined. T... more The relevance of new-onset atrial fibrillation (AF) after esophagectomy remains poorly defined. This study's primary goal is to better define the incidence, clinical patterns, and outcomes associated with the development of AF after esophagectomy. The study is a retrospective review of patients undergoing esophagectomy at a single academic center between May 1996 and December 2007. Patients with new-onset AF were evaluated by univariate and multivariate analyses for risk factors associated with AF onset and outcomes. New-onset AF was noted in 32 of 156 (20.5%) patients after esophagectomy. Most (16/32, 50%) developed AF within 48 h, and 28 of 32 (87.5%) developed new AF within 72 h of surgery. Pulmonary complications were more frequent in patients with AF than those without AF (59.4% vs. 15.3%, P < 0.01) and usually immediately preceded or occurred concurrently with AF. Anastomotic leaks were significantly more common in patients with AF than those without (28.1% vs. 6.45%, P…
International journal of critical illness and injury science, 2011
One of the hallmarks of modern medicine is the improving management of chronic health conditions.... more One of the hallmarks of modern medicine is the improving management of chronic health conditions. Long-term control of chronic disease entails increasing utilization of multiple medications and resultant polypharmacy. The goal of this study is to improve our understanding of the impact of polypharmacy on outcomes in trauma patients 45 years and older. Patients of age ≥45 years were identified from a Level I trauma center institutional registry. Detailed review of patient records included the following variables: Home medications, comorbid conditions, injury severity score (ISS), Glasgow coma scale (GCS), morbidity, mortality, hospital length of stay (LOS), intensive care unit (ICU) LOS, functional outcome measures (FOM), and discharge destination. Polypharmacy was defined by the number of medications: 0-4 (minor), 5-9 (major), or ≥10 (severe). Age- and ISS-adjusted analysis of variance and multivariate analyses were performed for these groups. Comorbidity-polypharmacy score (CPS) wa...
The polymorphonuclear neutrophil (PMN) has been implicated in the pathogenesis of endothelial cel... more The polymorphonuclear neutrophil (PMN) has been implicated in the pathogenesis of endothelial cell (EC) damage and organ injury following hemorrhagic shock. Pentastarch (PTS), a low substituted medium molecular weight (MW) colloid, improves hemodynamics in hypovolemic shock and cardiac surgery. No data exist comparing the immunomodulation of PTS and Ringer&#39;s lactate (RL) on the activation of PMN in hemorrhagic shock in vivo. Using an in vivo murine hemorrhagic shock model (blood withdrawal to maintain 50 mmHg x 45 min), circulating PMN were observed every 15 minutes using intravital microscopy on cremaster muscle. EC-PMN interactions (videorecorded and subsequently analyzed blindly), vessel leakage (live epifluorescence after injection of 50 mg/kg fluorescent albumin) and PMN expression of L-selectin (immunofluorescent monoclonal antibodies and flow cytometry) were evaluated in three resuscitation groups: PTS (7.14 mL/kg 10% pentastarch/0.9% NaCl + shed blood, n = 13), RL (RL [2 x shed blood volume] + shed blood, n = 13) and SHAM (0 hemorrhage, 0 resuscitation, n = 9). Significance was evaluated by ANOVA with Bonferroni correction. PMN rolling was significantly diminished in PTS and SHAM as compared to RL animals at all time points. Similar differences were found in PMN adherence to EC at most time points onwards from 15 minutes following resuscitation. In vivo vessel permeability was lowest in SHAM and PTS animals (mean 0.274 +/- 0.07 and 0.356 +/- 0.15, respectively, p &gt; 0.05) and highest in RL animals (0.667 +/- 0.09, p &lt; 0.001 vs PTS or SHAM). PMN L-selectin expression tended to be higher in the RL group than either SHAM and PTS groups. There were no flow-mechanics differences between groups (vessel diameter, mean red cell velocity, shear stress, shear rate). 10% pentastarch reduces RL-associated EC-PMN interactions and vessel leakage following hemorrhagic shock. These results support the use of low MW starches to resuscitate hemorrhagic shock, potentially reducing PMN-mediated tissue injury.
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Papers by David C. Evans
(comet or asteroid) during an interval of massive volcanic eruptions and changes in temperature and sea level.
There has long been fervent debate about how these events affected dinosaurs. We review a wealth of new data
accumulated over the past two decades, provide updated and novel analyses of long-term dinosaur diversity
trends during the latest Cretaceous, and discuss an emerging consensus on the extinction’s tempo and causes.
Little support exists for a global, long-term decline across non-avian dinosaur diversity prior to their extinction
at the end of the Cretaceous. However, restructuring of latest Cretaceous dinosaur faunas in North America led
to reduced diversity of large-bodied herbivores, perhaps making communities more susceptible to cascading
extinctions. The abruptness of the dinosaur extinction suggests a key role for the bolide
(comet or asteroid) during an interval of massive volcanic eruptions and changes in temperature and sea level.
There has long been fervent debate about how these events affected dinosaurs. We review a wealth of new data
accumulated over the past two decades, provide updated and novel analyses of long-term dinosaur diversity
trends during the latest Cretaceous, and discuss an emerging consensus on the extinction’s tempo and causes.
Little support exists for a global, long-term decline across non-avian dinosaur diversity prior to their extinction
at the end of the Cretaceous. However, restructuring of latest Cretaceous dinosaur faunas in North America led
to reduced diversity of large-bodied herbivores, perhaps making communities more susceptible to cascading
extinctions. The abruptness of the dinosaur extinction suggests a key role for the bolide