Publications by authors named "Kim Collins"

The highly reactive compound methylglyoxal (MG) can cause direct damage to cells and tissues by reacting with cellular macromolecules. MG has been identified as a biomarker associated with increased sepsis-induced mortality. Patients undergoing septic shock have significantly elevated circulating MG levels compared to postoperative patients and healthy controls.

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The strong, long-range electrostatic forces described by Coulomb's law disappear for ions in water, and the behavior of these ions is instead controlled by their water affinity - a weak, short-range force which arises from their charge density. This was established experimentally in the mid-1980s by size-exclusion chromatography on carefully calibrated Sephadex® G-10 (which measures the effective volume and thus the water affinity of an ion) and by neutron diffraction with isotopic substitution (which measures the density and orientation of water molecules near the diffracting ion and thus its water affinity). These conclusions have been confirmed more recently by molecular dynamics simulations, which explicitly model each individual water molecule.

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Injury to a fetus or neonate during delivery can be due to several factors involving the fetus, placenta, mother, and/or instrumentation. Birth asphyxia results in hypoxia and ischemia, with global damage to organ systems. Birth trauma, that is mechanical trauma, can also cause asphyxia and/or morbidity and mortality based on the degree and anatomic location of the trauma.

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As one of the leading causes of traumatic deaths in newborns, infants, and young children, there is no anatomic or microscopic feature that is pathognomonic for asphyxial deaths. Instead, pathologists rely on investigation information, including confessions and/or witness statements, and potential evidence at the scene. Twenty cases of homicidal newborn, infant, and young children asphyxial deaths were reviewed, which included death and police investigation reports and autopsy reports, as well as histology slides of lung sections.

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The phenol-phenolate anionic complex was studied in vacuo by negative ion photoelectron spectroscopy using 193 nm photons and by density functional theory (DFT) computations at the ωB97XD/6-311+G(2d,p) level. We characterize the phenol-phenolate anionic complex as a proton-coupled phenolate pair, i.e.

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The debate over the possible role of strong, low-barrier hydrogen bonds in stabilizing reaction intermediates at enzyme active sites has taken place in the absence of an awareness of the upper limits to the strengths of low-barrier hydrogen bonds involving amino acid side chains. Hydrogen bonds exhibit their maximal strengths in isolation, i.e.

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May-Thurner syndrome results from long-standing compression of the left common iliac vein (LCIV) and is characterized by the formation of intraluminal spurs leading to obstruction of blood flow and deep vein thrombosis (DVT). Increased intraluminal pressures may occur as a consequence of venous obstruction, which when coupled with other factors thought to further weaken venous wall integrity (ie, inflammation or hormonal imbalances) may produce spontaneous (nontraumatic) and potential lethal venous rupture.We report a case of DVT in a woman with previously undiagnosed May-Thurner syndrome and heterozygosity for factor V Leiden mutation on exogenous hormone therapy, with subsequent spontaneous rupture of the LCIV leading to fatal hemoperitoneum.

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Methamphetamine is a synthetic stimulant that can adversely affect the central nervous system and the immune system. Through various mechanisms, methamphetamine is toxic to neurons, endothelial cells, lymphocytes, granulocytes, and macrophages resulting in systemic damage. Reported is the sudden demise of an otherwise healthy 31-year-old woman with a history of stimulant abuse.

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Continuum electrostatics models for ions in water provide apparent long range electrostatic explanations for the forces on ions. However the electro-chemical free energy of solvation of ions resides largely in the first two water layers, which control the interfacial behavior of the ions and require explicit modeling to capture their distinctive behaviors. The resulting short range forces produce such surprising charge density-dependent behaviors as ion adsorption onto nonpolar surfaces, like charge aggregation of ions, and substantial ion pairing preferences, which arise largely from the affinity of specific ions for individual water molecules.

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Sudden cardiac deaths because of acute myocardial infarction (MI) constitute a significant percentage of the caseload for death investigators, coroners, and forensic pathologists. Clinicians use cardiac markers, highly sensitive and specific for myocardial damage, to screen living patients for acute MI; however, to this point, the utility of these markers in the autopsy setting has not been fully established. The current study included 10 decedents, five who died of acute MI, and five subjects who died of noncardiac disease.

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The majority of cardiac related deaths are due to ischemic heart disease, with the most common clinical scenario being severe coronary artery atherosclerosis resulting in left ventricular myocardial infarction. However, infarction of other cardiac chambers does occur, and often has specific clinical associations. We report a case of a 70-year-old man who suffered from left atrial infarction that resulted in a transmural rupture of his left atrium.

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Molecular dynamics simulations show significant like-charge pairing of guanidinium side chains in aqueous poly-arginine, while this effect is absent in aqueous poly-lysine containing ammonium-terminated side chains. This behavior of the guanidinium group is revealed also by protein database searches, having important biochemical implications. Combination of molecular dynamics simulations with explicit solvent and ab initio calculations employing a polarizable continuum model of water allows one to rationalize the formation of contact ion pairs between guanidinium cations in terms of individual interactions at the molecular level.

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In Drosophila oocytes achiasmate homologs are faithfully segregated to opposite poles at meiosis I via a process referred to as achiasmate homologous segregation. We observed that achiasmate homologs display dynamic movements on the meiotic spindle during mid-prometaphase. An analysis of living prometaphase oocytes revealed both the rejoining of achiasmate X chromosomes initially located on opposite half-spindles and the separation toward opposite poles of two X chromosomes that were initially located on the same half spindle.

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Ludwig angina is a rapidly progressing submaxillary, submandibular, and sublingual necrotizing cellulitis of the floor of the mouth that can have lethal consequences due to airway obstruction. Various aerobic and anaerobic microorganisms, and less often fungi, have been implicated to cause Ludwig angina, including oral flora such as streptococci and staphylococci. Early recognition and the use of parenteral antibiotics can prevent mortality and morbidity.

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The pediatric population has received considerable attention in the forensic community; the youth assailant of homicide, however, is understudied. The authors retrospectively reviewed all cases referred to the Forensic Pathology Section of the Medical University of South Carolina between January 1991 and May 2006. Cases included in the study were homicides in which 1 or more assailants were 19 years of age or younger.

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Elder neglect, one of the 6 forms of elder maltreatment, is difficult to diagnose and is underreported both in the scientific literature and to law enforcement. Recognizing fatal neglect is even more challenging especially with concurrent organic disease. Many entities can mimic elder neglect, and many age-related changes can result in pathology that may be confused with maltreatment.

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The fetus is subjected to mechanical forces during labor and delivery, which may result in traumatic injuries. Such injuries include intracranial hemorrhage, spinal cord lesions, cephalhematoma, cranial or peripheral nerve palsies, intraabdominal organ rupture, or bony fractures. Risk for perinatal trauma and mortality is increased in primigravidas, multiple gestations, abnormal presentations, maternal-fetal disproportion, oligohydramnios, forceps or vacuum extractions, and internal version maneuvers.

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Neuroleptic malignant syndrome (NMS) is a diagnosis of exclusion difficult to make due to a lack of pathognomonic features. Diagnosing NMS by postmortem examination becomes increasingly challenging when possible underlying brain pathology is obscured. The diagnosis is based on clinical history and laboratory findings.

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