Miracle-dz/UniFAR-FTUs huggingface dataset:
Mechanism of Inhibitory Action on Platelet Activation of a Phospholipase A2 Isolated from Lachesis muta (Bushmaster) Snake Venom

Summary Crude venom from Lachesis muta exhibited procoagulant, proteolytic and phospholipase A2 activities. A phospholipase A2, denoted LM-PLA2 was purified from L. muta venom to homogeneity, through a combination of chromatographic steps involving gel-filtration on Sephacryl S-200 HR and reverse phase chromatography on a C2/C18 column. LM-PLA2 presented a single polypeptide chain with an isoelectric point at pH 4.7 and apparent molecular weight of 17 kDa. Partial aminoacid sequence indicated a high degree of homology for LM-PLA2 with other PLA2 from different sources. LM-PLA2 displayed a potent enzymatic activity as measured by indirect hemolysis of red blood cells but it was neither lethal when injected i.p. into mice nor did it present anticoagulant activity. Furthermore, LM-PLA2 displayed a moderate inhibitory activity on the aggregation of rabbit platelets induced by low levels of ADP, thrombin and arachidonate. In contrast, platelet aggregation induced by high doses of collagen was strongly inhibited by LM-PLA2 as well as ATP-release. Treatment of the protein with p-bromophenacyl bromide or 2-mercapto-ethanol, as well as thermal inactivation studies, suggested that the platelet inhibitory effect of LM-PLA2 is dependent on its enzymatic activity. Thus, the platelet inhibitory activity of LM-PLA2 was shown to be dependent on the hydrolysis of plasma phospholipids and/or lipoproteins, most probably those rich in phosphatidylcholine. Surprisingly, lyso-phosphatidylcholine released by LM-PLA2 from plasma was shown to preferentially inhibited collagen-induced platelet aggregation, in contrast to other PLA2s, whose plasma hydrolytic products indistinctly affect platelet’s response to several agonists.
Optimization of continuous in vivo DOPA production and studies on ectopic DA synthesis using rAAV5 vectors in Parkinsonian rats

Viral vector‐mediated gene transfer is emerging as a novel therapeutic approach with clinical utility in treatment of Parkinson’s disease. Recombinant adeno‐associated viral (rAAV) vector in particular has been utilized for continuous l‐3,4 dihydroxyphenylalanine (DOPA) delivery by expressing the tyrosine hydroxylase (TH) and GTP cyclohydrolase 1 (GCH1) genes which are necessary and sufficient for efficient synthesis of DOPA from dietary tyrosine. The present study was designed to determine the optimal stoichiometric relationship between TH and GCH1 genes for ectopic DOPA production and the cellular machinery involved in its synthesis, storage, and metabolism. For this purpose, we injected a fixed amount of rAAV5‐TH vector and increasing amounts of rAAV5‐GCH1 into the striatum of rats with complete unilateral dopamine lesion. After 7 weeks the animals were killed for either biochemical or histological analysis. We show that increasing the availability of 5,6,7,8‐tetrahydro‐l‐biopterin (BH4) in the same cellular compartment as the TH enzyme resulted in better efficiency in DOPA synthesis, most likely by hindering inactivation of the enzyme and increasing its stability. Importantly, the BH4 synthesis from ectopic GCH1 expression was saturable, yielding optimal TH enzyme functionality between GCH1 : TH ratios of 1 : 3 and 1 : 7.
Clonogrouping, a Rapid Multiplex PCR Method for Identification of Major Clones of Listeria monocytogenes

ABSTRACT Three multiplex PCR assays were developed to identify the 11 most common Listeria monocytogenes clones in clinical and food samples; 270 (95.7%) of 282 strains of serogroups IVb, IIb, IIa, and IIc were identified accurately. This novel tool is a rapid and efficient alternative to multilocus sequence typing for identification of L. monocytogenes clones.
Reverse Mismatch Pattern in Cardiac 18F-FDG Viability PET/CT Is Not Associated With Poor Outcome of Revascularization: A Retrospective Outcome Study of 91 Patients With Heart Failure

Purpose Revascularization strategies in patients with ischemic heart failure (HF) should be based on evidence of reversible perfusion defects and myocardial viability. Myocardial viability assessment is preferably based on dual isotope PET using perfusion and metabolism tracers. However, in a nonnegligible subset of HF patients, reverse mismatch (RM) pattern (reduced glucose uptake relative to perfusion) of unknown origin is observed. We aimed to investigate determinants of RM and the impact of RM on the subsequent improvement in left ventricular function by revascularization. Patients and Methods Ninety-one patients (12 women, 25 with diabetes) with HF undergoing 82Rb perfusion PET and hyperinsulinemic-euglycemic clamp 18F-FDG viability PET were retrospectively reviewed. Results Follow-up time was 12 to 33 months. In 30 of 91 patients, hypometabolic myocardium exceeded the percentage of hypoperfused myocardium; however, only in 12 of 91 patients was the RM considered significant (percentage RM in the left ventricle, 42.5 ± 12.9 [reverse patients] vs 14.1 ± 8.6 [scar and hibernation patients]; P < 0.001). Diabetes status per se did not predict RM, but a significant inverse correlation between insulin sensitivity and RM was observed. The frequency of hospitalization, cardiac death, and myocardial infarctions were not significantly higher in RM patients. Reverse mismatch patients benefited from revascularization to the same extent as patient with normal metabolic patterns. Conclusions Reverse mismatch is common among HF patients (~15%) and is inversely correlated to insulin sensitivity. It is not, however, associated with increased cardiac morbidity and mortality and does not predict a worse outcome after revascularization.
Approaches to quality assurance: the federal role.

T HE federal government began paying directly for medical services in the late 1960s. Since that time, some form of quality assurance has been required for patients whose care is government funded. During the 20 years since the implementation of Medicare both the organization and the methods of medical quality assurance have changed dramatically. Most commentary on the federal role has focused on organizational issues: movement from Utilization Review to Professional Standards Review Organizations to Professional Review Organizations. This paper describes a parallel evolution in how quality assurance is conducted. The evolution in quality assurance methods, dramatic in scope and impact, has been closely linked to organizational change. The methods of quality assurance now available could not have developed without such things as Professional Standards Review Organizations and Professional Review Organizations. Both modern quality assurance and future innovations in this field depend heavily on areawide data sets for an analytic base and on an organization able to use areawide information. Quality assurance in medical care has passed through three distinct phases since the passage of Medicare: a period during which measurement of capacity was the primary tool available; a period when emphasis shifted to criteria-based quality assurance; and the eventual adoption of a statistical approach to quality assurance. As new methods have appeared, the old have survived so that all three types of efforts can currently be found in operation. Future advances in quality assurance can be anticipated in the potential integration of the statistical approach with epidemiologic data, thus permitting population-based rather than institution-based analyses of the effects of care.
The structural basis for the recognition of acetylated histone H4 by the bromodomain of histone acetyltransferase Gcn5p

The bromodomain is an ∼110 amino acid module found in histone acetyltransferases and the ATPase component of certain nucleosome remodelling complexes. We report the crystal structure at 1.9 Å resolution of the Saccharomyces cerevisiae Gcn5p bromodomain complexed with a peptide corresponding to residues 15–29 of histone H4 acetylated at the ζ‐N of lysine 16. We show that this bromodomain preferentially binds to peptides containing an N‐acetyl lysine residue. Only residues 16–19 of the acetylated peptide interact with the bromodomain. The primary interaction is the N‐acetyl lysine binding in a cleft with the specificity provided by the interaction of the amide nitrogen of a conserved asparagine with the oxygen of the acetyl carbonyl group. A network of water‐mediated H‐bonds with protein main chain carbonyl groups at the base of the cleft contributes to the binding. Additional side chain binding occurs on a shallow depression that is hydrophobic at one end and can accommodate charge interactions at the other. These findings suggest that the Gcn5p bromodomain may discriminate between different acetylated lysine residues depending on the context in which they are displayed.
Fourteen-band hysteresis controller of the fifteen-level packed U cells converter

In this paper, authors propose a novel fourteen-band hysteresis technique to control the fifteen level packed U cells (PUC) converter. This topology was first introduced in [1]. It combines advantages of the flying capacitor and the cascaded H-bridge topologies. The study of the novel converter allows the establishment of the switches gates signals equations. In case of rectifier operation, the proposed fourteen-band controller is designed to draw a sinusoidal line current with a unity power factor. Harmonics contents of line current and rectifier input voltage are then very reduced which permits the reduction of the rating of active and passive filters resulting on a very high energetic efficiency and a reduced installation cost. The fifteen level PUC transformerless inverter has the advantage to operate with a single DC source. A fourteen-band technique is performed to control the auxiliary DC buses and to draw a nearly sinusoidal load current. The proposed concepts were verified by simulations performed in the Matlab Simulink and SimPowerSystem environments.
Quantitative characterization of meiotic chromosome organization

Sexual reproduction relies on a specialized program of cell division called meiosis to generate haploid gametes from diploid germ cells. In order for chromosome segregation to occur accurately, homologous chromosomes must pair, synapse, and undergo crossover recombination. These physical and biochemical interactions occur in coordination with large-scale reorganization of meiotic chromosomes. To understand the relationship between chromosome organization and the regulation of recombination, we developed an automated image analysis pipeline that combines the throughput of population-based biochemical assays with the temporal and contextual information provided by cytological methods. This new technique enables us to monitor temporal changes in the distribution of meiotic double strand breaks (DSBs) on a chromosome-wide basis and to correlate that distribution with features of meiotic chromosome organization. We applied this technique to meiotic chromosomes in the nematode Caenorhabditis elegans and observed that the distribution of DSBs is dynamic during prophase and shifts from a distribution that mirrors the distribution of crossovers to one that is more uniform. This shift correlates with isotropic, recombination-independent elongation of chromosomes along the axis and is insensitive to defects in recombination, variation in the number of DSBs, and variation in chromosome axis length. This work reveals a novel dynamic aspect of meiotic DSB formation and quantifies, for the first time, statistical features of meiotic chromosome organization in C. elegans.
Lack of lipid phosphate phosphatase‐3 in embryonic stem cells compromises neuronal differentiation and neurite outgrowth

Background: Bioactive lipids such as lysophosphatidic acid (LPA) and sphingosine‐1‐phosphate (S1P) have been recently described as important regulators of pluripotency and differentiation of embryonic stem (ES) cells and neural progenitors. Due to the early lethality of LPP3, an enzyme that regulates the levels and biological activities of the aforementioned lipids, it has been difficult to assess its participation in early neural differentiation and neuritogenesis. Results: We find that Ppap2b−/− (Lpp3−/−) ES cells differentiated in vitro into spinal neurons show a considerable reduction in the amount of neural precursors and young neurons formed. In addition, differentiated Lpp3−/− neurons exhibit impaired neurite outgrowth. Surprisingly, when Lpp3−/− ES cells were differentiated, an unexpected appearance of smooth muscle actin‐positive cells was observed, an event that was partially dependent upon phosphorylated sphingosines. Conclusions: Our data show that LPP3 plays a fundamental role during spinal neuron differentiation from ES and that it also participates in regulating neurite and axon outgrowth. Developmental Dynamics 241:953–964, 2012. © 2012 Wiley Periodicals, Inc.
Nanoporous gold–alumina core–shell films with tunable optical properties

Tuning of the localized surface plasmon resonance (LSPR) of nanoporous metals is at the heart of manipulating light within extremely small volumes for the implementation of optical devices at the nanoscale. In this work, nanoporous gold–alumina core–shell films with fixed gold skeletons and different thicknesses of alumina shells are fabricated using chemical corrosion and subsequent atomic layer deposition. Optical transmission of the nanoporous composite films can be tailored through LSPR excitations of the three-dimensional gold skeleton and the alterable alumina shells as the covering dielectric. A 92 nanometer red-shift of the LSPR band is attained via its dielectric medium dependence and the comparable decay length with pore size. The widely tunable optical transmission and significantly improved stability thus suggest incorporating nanoporous gold–alumina into promising nano-devices with reliable performance. Low temperature surface decoration (<100 °C) provides a universal route to tune the optical properties while retaining the spatial geometry of the metallic nanostructures.
Numerical study of the cerebrospinal fluid (CSF) dynamics under quasistatic condition during a cardiac cycle

We present a method to perform a numerical simulation of the flow dynamics of cerebrospinal fluid (CSF) based on anatomical magnetic resonance images (MRI). The computational fluid dynamics (CFD) software, written in language C, integrates different numerical schemes to solve the governing equations. The time derivatives were discretized using the Crank-Nicolson scheme. The equation of continuity was modified by introducing an artificial compressibility and discretized by a finite difference scheme. The meshed boundary of the CSF was immersed in a marker-and-cell staggered grid to take into account the fluid-structure interactions. Equations of hydrodynamics were solved with an iterative method under different quasi-static conditions. The anatomical basis of our simulations was generated from individual MRI scans. The surface of the anatomical flow channels of interest was extracted by segmentation and triangulated. In parallel to the acquisition of the anatomical data, CSF flow has been measured by MRI. To characterize a whole cardiac cycle, sixteen equidistant velocity measurements have been performed. In addition, a home made software was implemented to visualize computed data (velocities, pressure).
Stumbling Corrective Responses During Treadmill‐Elicited Stepping in Human Infants

This study examined stumbling corrective (tripping) responses to mechanical disturbances applied to the foot during stepping in healthy human infants, in whom independent walking had not yet developed. During treadmill‐elicited stepping, a foam‐padded baton instrumented with a force transducer was used to deliver light touches to either the dorsum or the side of the foot at various times of the step cycle. Disturbances to the dorsum of the foot during the swing phase resulted in a general enhancement of flexor activity, including a significant facilitation in the tibialis anterior muscle and an increase in knee flexion during swing. There was also an increase in step cycle duration. Stance phase disturbances resulted in a significant inhibitory effect in the quadriceps muscle and after early stance disturbances, a significant prolongation of the stance phase duration. Disturbances applied to the side of the foot during the swing phase of forward stepping did not result in any effect on the kinematic pattern. If the infant was stepping sideways, however, disturbances to the side of the foot resulted in an increase in flexion during the swing phase. The results show that infants have a phase‐dependent reflex response to light touches applied to the foot. Furthermore, the reflex response is location specific and task specific. Thus, much of the sophistication necessary for controlling sensory inputs in walking is present well before the onset of independent walking.
An analysis of the primary cardiovascular reflex effects of stimulation of the carotid body chemoreceptors in the dog

It has been shown previously that stimulation of the carotid body chemoreceptors in dogs breathing spontaneously causes variable changes in heart rate (Bernthal, Greene & Revzin, 1951; Daly & Scott, 1958, 1959, 1962). A detailed study revealed that the change in heart rate was dependent upon at least two mechanisms. The first of these is a primary cardiac reflex arising from the chemoreceptors themselves, which causes slowing of the heart. The other mechanism was identified as occurring secondarily to the concomitant reflex increase in respiratory minute volume and causes an increase in heart rate. This secondary effect is due, at least in part, to a stretch reflex from the lungs and to a lowering of the arterial blood PCO2, and may be excluded by maintaining pulmonary ventilation constant by means of a pump (Daly & Scott, 1958, 1959). When pulmonary ventilation is maintained constant in this way during chemoreceptor stimulation, the primary cardiac reflex response becomes apparent (Daly & Scott, 1958). The purpose ofthe present investigation was to discover the mechanisms by which the primary cardiac response was brought about and to make observations on the changes in vascular resistance resulting from stimulation of the carotid bodies. Our results have been reported briefly elsewhere (Daly & Scott, 1961, 1962).
The Influence of Socioeconomic and Environmental Factors on Health and Obesity in Rural Appalachia

A recursive system of ordered self assessed health (SAH) and a binary indicator of obesity were used to investigate the impact of socioeconomic and environmental factors on health and obesity in the predominantly rural Appalachian state of West Virginia. Behavioral Risk Factor Surveillance System (BRFSS) data together with county specific socioeconomic and built environment indicators were used in estimation. Results indicate that an individual’s risk of being obese increases at a decreasing rate with per capita income and age. Marginal impacts show that as the level of education attainment increases, the probability of being obese decreases by 3%. Physical inactivity increases the risk of being obese by 9%, while smoking reduces the risk of being obese by 14%. Fruit and vegetable consumption lowers the probability of being obese by 2%, while each hour increase in commuting time raises the probability of being obese by 2.4%. In addition, individuals living in economically distressed counties are less likely to have good health. Intervention measures which stimulate human capital development and better land use planning are essential policy elements to improving health and reducing the incidence of obesity in rural Appalachia.
Radiation therapy for advanced and metastatic melanoma

Radiation therapy (RT) is an important modality in cancer treatment. However, the general perception is that melanoma is radio‐resistant. High quality clinical trials are helping to establish the place of RT in select scenarios of advanced disease at primary, regional, and distant sites. New RT techniques need to be integrated with effective new systemic therapies within a multidisciplinary environment to ensure optimum patient outcomes. It is important that radiation oncologists embrace this opportunity. J. Surg. Oncol. 2014 109:370–375. © 2013 Wiley Periodicals, Inc.
Instructive role of M‐CSF on commitment of bipotent myeloid cells involves ERK‐dependent positive and negative signaling

M‐CSF and G‐CSF are instructive cytokines that specifically induce differentiation of bipotent myeloid progenitors into macrophages and granulocytes, respectively. Through morphology and colony assay studies, flow cytometry analysis of specific markers, and expression of myeloid transcription factors, we show here that the Eger/Fms cell line is composed of cells whose differentiation fate is instructed by M‐CSF and G‐CSF, thus representing a good in vitro model of myeloid bipotent progenitors. Consistent with the essential role of ERK1/2 during macrophage differentiation and defects of macrophagic differentiation in native ERK1−/− progenitors, ERK signaling is strongly activated in Eger/Fms cells upon M‐CSF‐induced macrophagic differentiation but only to a very small extent during G‐CSF‐induced granulocytic differentiation. Previous in vivo studies indicated a key role of Fli‐1 in myeloid differentiation and demonstrated its weak expression during macrophagic differentiation with a strong expression during granulocytic differentiation. Here, we demonstrated that this effect could be mediated by a differential regulation of protein kinase Cδ (PKCd) on Fli‐1 expression in response to M‐CSF and G‐CSF. With the use of knockdown of PKCd by small interfering RNA, we demonstrated that M‐CSF activates PKCd, which in turn, inhibits Fli‐1 expression and granulocytic differentiation. Finally, we studied the connection between ERK and PKCd and showed that in the presence of the MEK inhibitor U0126, PKCd expression is decreased, and Fli‐1 expression is increased in response to M‐CSF. Altogether, we demonstrated that in bipotent myeloid cells, M‐CSF promotes macrophagic over granulocytic differentiation by inducing ERK activation but also PKCd expression, which in turn, down‐regulates Fli‐1 expression and prevents granulocytic differentiation.
Energy system contributions in middle-distance running events.

The aim of this study was to estimate the energy contributions in middle-distance running events for male and female university athletes. The oxygen uptake (VO2) response during high-speed running was measured directly during exhaustive treadmill tests. Muscle mass was estimated using anthropometry. Each athlete completed an average of three races over 400 m, 800 m or 1500 m. Five minutes after each race, they provided a blood sample for determination of blood lactate concentration. For each race, energy cost, which was expressed as oxygen equivalents, was calculated as the sum of the aerobic and anaerobic components. The aerobic contribution was calculated as the sum of oxygen stores (2.3 ml O2.kg body mass-1) and total VO2 (based on the VO2 response to treadmill running). The anaerobic contribution was calculated as the sum of the energy available from phosphocreatine stores (37 ml O2.kg muscle mass-1) and the energy from glycolysis (3.0 ml O2.kg body mass-1 per mmol.l-1 increase in blood lactate concentration). For the women, the anaerobic energy contributions for the 400 m, 800 m and 1500 m averaged 62%, 33% and 17%, respectively. For the men, the anaerobic contributions averaged 63%, 39% and 20%, respectively. This information will help coaches and sport scientists to design and implement individualized training programmes.