bluuebunny/crossref_metadata_2025_split huggingface dataset:
COMPARATIVE EVALUATION OF PHAMACODYNAMICS AND NEURONAL OXIDATIVE STRESS ELICITED BY LARGE DOSES OF ARTESUNATE IN COMBINATION WITHMEFLOQUINE OR AMODIAQUINE IN Plasmodium berghei INFECTED MICE
Authors: Wilson Francis Daniel Temitope 
Published: June 2021

Background: Artemisinins in combination with other conventional antimalarials have been found to elicit greater schizonticidal and gametocidal activity than other antimalarial drugs. However, their pharmacokinetic misfit has raised substantial concerns over their future pharmacodynamic potentials, which include restoration of neutrophil function during covalescence or at full recovery.Method: A total of forty‐five mice (Mean weight = 22.1g) intraperitoneally infected with P. berghei at a dose of 5 × 107 parasitized erythrocytes, were randomized into 3 treatment groups of 15 mice per dosing regimen. The animals were scored for mortality, clearance of parasitaemia and pigmented neutrophils. .Results: Administration of escalated doses of artesunate‐amodiaquine and artesunate – mefloquine resulted in dose‐dependent but non significant (P < 0.05) decreases in parasite clearance time (12 – 28.8 h for artesunate + amodiaquine; 16.5 – 27 h for artesunate + mefloquine) and parasite reduction rate (0.65 – 074 % parasite/h and 0.64 −0.78 % parasite/h). While parasitaemia correlated positively but non‐significantly (r = 0.065; P < 0.05), the neutropenia (4472.3 ± 240 vs. 1709.5 ± 17.8 cells/mm3; P < 0.05) and pigmented neutrophils (308.2±2.4 cells/mm3) elicited by P. berghei infection was also not corrected by the two artesunate – based regimens.Conclusion: Based on the results of this study, it can be concluded that the artesunate based combination therapies lack neutrophil restoration ability and oxidative stress corrective function in spite of their antiparasitic efficacy.
The divergent role of epoxyeicosatrienoic acids in the regulation of renal function in normotensive and two‐kidney one‐clip Goldblatt hypertensive rats
Authors: Kopkan Libor , Walkowska Agnieszka , Thumova Monika , Skaroupkova Petra , Imig John D. , Cervenka Ludek 
Published: June 2021

To assess the renal function in anesthetized Hannover Sprague‐Dawley rats with induced renovascular hypertension for 27 days (2K1C) and normotensive sham operated control rats during acute inhibition of epoxyeicosatrienoic acids (EETs) generation in the kidney, epoxygenase inhibitor, methylsulfonyl‐6‐(2‐propargyloxyphenyl) hexanamide (MS‐PPOH, 12 μmol/L), was continuously administered directly into the nonclipped kidney at a rate 0.3 mL/hour for over 60 minutes. Glomerular filtration rate (GFR) and renal plasma flow (RPF) were determined by Inulin and PAH clearance, respectively.Basal renal function of the nonclipped kidney was not different (GFR 0.79±0.07 vs. 0.74 ±0.03 mL/min/g; RPF 2.03±0.09 vs. 2.04 ±0.13 mL/min/g and sodium excretion 1.85±0.31 vs. 1.51 ±0.29 μmol/min/g) in hypertensive 2K1C rats (n=8) compare to sham operated control rats (n=8). Although administration of MS‐PPOH caused significant decreases in GFR (15±3%), RPF (18±4%) and sodium excretion (42±9%) in sham operated rats, MS‐PPOH did not significantly alter renal function in the nonclipped kidney of 2K1C rats.These data further support the notion that EETs contribute in modulation of renal vasodilatation and natriuresis which might be impaired in 2K1C rats due to deficiency of intrarenal EETs in this hypertensive model.
Hyperpolarized 3He magnetic resonance imaging of ventilation after bacterial lipopolysaccharide exposure in mice
Authors: Thomas Abraham , Voltz James , Fubara Boma , Driehuys Bastiaan , Zeldin Darryl 
Published: June 2021

Introduction: Traditional lipopolysaccharide (LPS) inhalation studies focus on histology, lung function and inflammatory mediator release. This study utilizes hyperpolarized (HP) 3He MRI to elucidate regional differences in ventilation following LPS exposure in mice.Methods: C57BL/6 mice were intratracheally dosed with high dose LPS (50 μg, N=2), low dose LPS (15–30 μg, N=7) or normal saline (NS) (N=2) and then imaged by HP 3He MRI.Results: There is proximal (2nd or 3rd order) bronchial tree distension in 50 μg LPS dosed mice that is not evident at lower doses (Table 1). Preliminary results indicate subsegmental ventilation defects (VD) are distributed evenly throughout the lungs of LPS dosed mice. Further, VD number is dose dependent (Table 1).Conclusions:LPS induced VD and proximal bronchial tree distension are dose dependent. As proximal bronchi distend in LPS dosed mice, airway hyperresponsiveness likely results from more distal airway constriction.Funding: NIEHS/NIH Division of Intramural Research and NCRR/NCI national resource funding.
Effectiveness of the Hybrid Model of Case Based Teaching in a Medical Pharmacology Class
Authors: Rajasekaran Senthil Kumar , Vaithilingam Andy , Armstrong Elizabeth 
Published: June 2021

An alternative pedagogical strategy to the routine didactic format of lectures has long been sought after by instructors in medical schools. We designed this study to investigate the effectiveness of our hybrid model of case based teaching by comparing it with the traditional didactic form of delivery of lecture material. Students were divided into two groups and the study was conducted for two weeks. On week‐I group A students were taught a topic using the case based teaching methodology while group B students were taught the same topic using the didactic lecture format. On week‐II, the groups were crossed over in terms of teaching strategies. The learning outcome was measured by a MCQ test. As indicated in table‐1, the use of a hybrid model of case based teaching methodology showed a significantly enhanced student academic performance compared to the traditional didactic lecture format. As evidenced in table‐2 this performance appeared to be independent of subject matter, student group composition, order and type of topics presented. Students appreciated the significance of clinical application of basic science concepts in accordance with the Kolb's theory of experimental learning.We conclude that such a hybrid format of delivering pharmacology content has greatly improved the learning outcome.
An investigation of learning styles in undergraduate students studying physiology.
Authors: Kay Ian Stuart , Kaur Raminder 
Published: June 2021

It is well established that students learn in a variety of ways– visual (V), auditory (A), read/write (R) and kinaesthetic (K). Determining the preferred style of learning of an individual student can be assessed using a VARK questionnaire. VARK questionnaires were administered to 220 first year students reading for a degree in Biological or Biomedical Science (BS/BMS) and 60 students reading for a degree in Speech Therapy (ST) – completion rates were 44.5% (n=100) for the BS/BMS cohort and 60% (n=40) for the ST cohort.Of the BS/BMS cohort, 64% were multimodal learners (67% were bimodal, 30% trimodal and 3% quadmodal) whilst 36% preferred a single learning style. For those who expressed a single preferred learning style, V learners accounted for 8%, A learners for 14%, R learners 25% whilst the remaining 53% were K learners.Analysis of the ST cohort showed similar results to those of the BMS cohort – 65% were multimodal (54% were bimodal, 38% trimodal and 8% quadmodal) whilst 35% expressed the preference of a single mode. Of those who expressed preference for a single style, 31% were V learners, 23% A, 38% R whilst the remaining 8% were K. This data suggests differences in learning styles between these two cohorts of students, which requires consideration when they are taught physiology.
Changes in zygapophysial (Z) joint synovial folds following induced segmental hypomobility in the rat
Authors: Cramer Gregory D. , Little Joshua W. , Henderson Charles N.R. , Daley Clover J. 
Published: June 2021

Synovial folds (SFs) are part of the normal anatomy of the Z joints. Although degenerative changes and adhesions have been identified in hypomobile Z joints, putative changes in SFs have not been previously studied. Using an established, IACUC approved, rat model, 3 contiguous segments (L4, L5, L6) were fixed with a specially engineered, surgically implanted, vertebral fixation device. Spinal segments of control rats (n=24 animals, 88 joints) were compared with those of animals with 4, 8, 12, or 16 weeks of fixation (n=16 animals, 54 joints). At the end of the experimental period, deep anesthesia was induced, followed by transcardial perfusion with fixative. Tissue was embedded in paraffin, sectioned, stained, and examined and photomicrographed using bright field microscopy. The number of Z joint quadrants with SFs was determined for each joint (left and right L4/L5 and L5/L6). Average number of quadrants with SFs was calculated for each group. Results: SFs were found in all joints. Significant differences were found among and between groups (ANOVA, p<0.001) with joints of control animals of each time period having larger synovial folds than fixation animals of the same time period (Tukey post hoc, wks: 4, p<0.05; 8, p<0.001; 12, p<0.005; 16, p<0.001). We conclude that hypomobility of rat Z joints results in regression of synovial folds.Support: NCMIC administered by FCER (Grant # 97‐10‐18).
TATA box binding protein (TBP) recruitment to the U1 gene promoter is disrupted by substituting a U6 proximal sequence element (PSEA) for the U1 PSEA
Authors: Barakat Nermeen , Stumph William E. 
Published: June 2021

Most of the spliceosomal small nuclear RNAs (U1, U2, U4, and U5) are synthesized by RNA polymerase II, but U6 snRNA is synthesized by RNA polymerase III. In Drosophila melanogaster. transcription of all snRNA genes requires a unique proximal promoter element, the PSEA. Surprisingly, the RNA polymerase specificity of the snRNA genes is determined by a few nucleotide differences between the PSEAs in the two classes of genes. In both classes, the PSEA is recognized by the small nuclear RNA activating protein complex (DmSNAPc). Previous transfection assays demonstrated that Pol II was unable to initiate transcription from a U1 promoter that contained the U6 PSEA. We have now used chromatin immunoprecipitation assays to determine at which step Pol II pre‐initiation complex assembly is disrupted when the U1 promoter contains a U6 PSEA. Interestingly, we found that DmSNAPc stably assembled on a U1 promoter that contained either the U1 or the U6 PSEA. However, although TBP was recruited to the wild type U1 promoter, TBP failed to assemble in vivo on the U1 promoter that contained the U6 PSEA. These results indicate that changing the U1 PSEA to a U6 PSEA had no effect on the binding of DmSNAPc, but it instead suggests that DmSNAPc is in the wrong conformation when bound to a U6 PSEA to recruit TBP to the U1 promoter.N.B. is a recipient of the Arne N. Wick Predoctoral Research Fellowship from the California Metabolic Research Foundation.
A simple assay for detection of small‐molecule redox activity
Authors: Lor Leng Anne , Schneck Jessica , McNulty Dean E , Diaz Elsie , Brandt Martin , Thrall Sara H. , Schwartz Benjamin 
Published: June 2021

In our research, we found that high throughput screens against certain targets, such as cysteine proteases and metal containing enzymes, often yield undevelopable hits because of their lack of specificity and irreversible nature. Weeding through these undesirable hits to get to those of interest can often be difficult, negatively impacting the chance of success in drug discovery. In order to better understand the mechanism of this inhibition, LC/MS/MS analysis was performed with cathepsin L (cat L), a cysteine protease. Incubation of these undesirable compounds with cat L resulted in specific oxidation of the active site cysteine. Based on this mechanism of inhibition, a surrogate high throughput fluorescence assay was developed to measure the tendency of compounds to oxidize enzyme targets. In this assay, reactive compounds catalyze two 1 electron transfers from DTT to resazurin, resulting in the formation of the fluorescent resorufin. Using this assay, we were able to show that a fluorescence increase was observed only with suspected redox inhibitors, and not with known tool compounds. Finally, we tested 400 compounds from a recent drug discovery project, and compared their reactivity in this assay against their potency with the target of interest. Compounds that clearly inhibit via this mechanism could easily be picked out from those that specifically inhibit the target. Hence this detection assay serves as a valuable tool for quickly triaging redox active compounds from HTS campaigns.GlaxoSmithKline Pharmaceuticals, Collegeville PA
Comparison of Protein‐Protein Interactions between BLIP and Class A Beta‐Lactamases
Authors: Nguyen Toan D , Wang Jihong , Mai Tu T , Pham Ngoc , Zhang Zhen , Palzkill Timothy , Chow Dar‐Chone 
Published: June 2021

The goal of our project is to determine and compare the binding thermodynamics of the interaction between β‐lactamase Inhibitor Protein (BLIP) mutants and Class A β‐Lactamases using ITC. We have previously determined the thermodynamics of binding interactions between TEM‐1, class A β‐lactamase family, and a set of alanine substituted contact residue mutants of BLIP (Wang J., et al. JBC. 2007; 282:17676–84). We have extended our approach to other members of class A β‐lactamases. Here, we report the binding thermodynamics between the inactive TEM‐1 mutant (S70A) and BLIP. We find that the alanine substitution of the active site Ser70 of TEM‐1 results in the lowering of the iso‐enthalpic temperature, which is more enthalpically favorable. The binding between BLIP and Bla1, another class A β‐lactamase, is dominated by an entropy driven force with an extrapolated iso‐enthalpic temperature of 42oC. Its binding heat capacity change is ∼ −450 cal/mol.K (∼ 20% less negative than that of BLIP/TEM‐1). However, the BLIP mutant W150A interaction with Bla1 shows a non‐linear relationship between the binding enthalpy and temperature with a positive binding heat capacity change at low temperature and a negative binding heat capacity change at high temperature, which is contrary to the general observation that the heat capacity change is negative for protein‐protein interactions.Support from AHA & UH to D.C. and NIH AI32956 to T.P.
Cell Adhesion and Fibrosis Affect the Mechanical and Electrical Coupling Of Cardiomyocytes in Human Atrial Fibrillation
Authors: Bodi Ilona , Jessen Walter , D'souza Karen , Koch Sheryl , Akhter Shahab , Wolf Randall , Schwartz Arnold , Aronow Bruce 
Published: June 2021

Background: Atrial fibrillation (AF) is the most common sustained arrhythmia. Long term AF leads to extensive structural remodeling with progressive contractile and electrophysiological dysfunction and system‐wide sequelae. We compared gene expression profiles of left atrial appendages from patients suffering from AF to normal atrial tissue from patients without history of AF.Methods and Results: The study consisted of three groups of patients; those with no history of AF in sinus rhythm (SR) and patients undergoing cardiac Mini‐Maze surgery for paroxysmal AF (PAF) and chronic AF (CAF). Gene expression analysis was carried out using Affymetrix microarrays and confirmed by western‐blot. Relative to SR controls, PAF and CAF samples showed statistically significant increases in the expression of genes associated with TGF‐β signaling and focal adhesion, including BMP6, CTGF, DPT, FN1, FST, JAM2, POSTN, SMAD7 and TNFAIP6. Increased expression of POSTN has also been implicated in myocyte hypertrophy in human ventricle during end‐stage heart failure. Dysregulated expression of TRDN, HDAC9, MYL2, TPM3 and TNNI3, significantly associated with calcium signaling, was only identified in patients with CAF. A key biomarker of inflammation, IFNG, was significantly upregulated between PAF and CAF. Conclusions: Our results strongly support the hypothesis that therapeutic measures designed to limit the extent of TGF‐β signaling and fibrosis such as the use of the ACEI losartan which induces regression of severe myocardial fibrosis, may be highly effective at limiting long‐term electromechanical dysfunction.
The functional analysis for the association of ALOX5 polymorphisms with asthma
Authors: Chang Hun‐Soo , Park Se‐Min , Park Jong Sook , Jang An‐Soo , Park Sung Woo , Park Byung Lae , Shin Hyoung Doo , Park Choon‐Sik 
Published: June 2021

The leukotrienes constitute a group of arachidonic acid‐derived compounds suggesting important roles in inflammation and immediate hypersensitivity. ALOX5 is a key enzyme required for the production of the cysteinyl‐leukotrienes.We genotyped five SNPs among these polymorphisms in a Korean population. The ratio of major allele homozygote of −754C>G and +21757G>A, which were located on promoter region and intron 3 of ALOX5, respectively, were higher in asthmatics than those in normal subjects (p = 0.001). In haplotype analysis, the frequency of ht1 were significantly higher in asthmatics (p = 0.001), and that of ht5 were lower in asthmatics (p = 0.007). Using reporter assay and Real time‐PCR, we revealed that genotypes on −754C>G affected the promoter activity followed by mRNA expression. Furthermore, we found genotypes on +21757G>A affected on the production of a novel alternatively spliced variant of ALOX5 resulting protein which lack lipoxygenase domain. And we revealed that genotypes on +21757 G>A affected by mRNA expression.Our results suggest that the ALOX5 polymorphisms may affect on the gene expression and/or alternative splicing of ALOX5 and are associated with the development of asthma.* This study was supported by a grant of the Korean Health 21 R&D project, Ministry of Health & Welfare, Republic of Korea (01‐PJ10‐PG6‐01GN14‐0003).
Why does a defect in choline kinase beta cause muscular dystrophy in mice?
Authors: Wu Gengshu , Vance Dennis 
Published: June 2021

Muscular dystrophies (MD) are a group of more than 30 genetic diseases characterized by progressive weakness and degeneration of the skeletal muscles. There is no specific treatment to stop or reverse any form of MD due to limited knowledge. We recently uncovered a natural mutation (rmd) in the Chkb gene that resulted in a complete loss of choline kinase (CK) activity in skeletal muscle, and the mice developed severe and progressive hindlimb MD. It is the first demonstration of a defect in a phospholipid biosynthetic enzyme causing MD. Why does muscular dystrophy occur? We observed decreased phosphatidylcholine (PC)/phosphatidylethanolamine (PE) ratio both in hindlimb muscle and in mitochondria associated with sarcolemmal integrity and megamitochondria formation. Decreased PC level is due to three factors: down‐regulated CTP:phosphocholine cytidylyltransferase (CT) activity, the rate‐limiting enzyme for PC biosynthesis; increased PC turnover due to increased phospholipase activity, and a limited source of phosphocholine in Chkb−/– mice. In vivo experiments further demonstrated that the incorporation ability of 3H‐choline into PC was significantly decreased in affected muscle. Decreased regeneration ability of Chkb−/–mice may also contribute to muscular dystrophy. In affected muscle there was increased expression of myostatin and decreased proliferating cell nuclear antigen (PCNA).This research was supported by a grant from Alberta Heritage Foundation for Medical Research and Canadian Institutes of Health Research.
On the differential lipolytic capabilities of heart kidney, testis and spleen for young adult guinea pig. A chromatographic study
Authors: Helmy Fatma M. , White Sanese , Amiri Sohrab , Amiri Rohina , Saliu Aminat , Juracka Amal 
Published: June 2021

We have recently reported the preferential deacylation of cardiolipin (CL) in a variety of mammalian myocardia and pectoral muscle of some birds by endogenous phospholipases (PLA1 and/or PLA2) during in vitro incubation at pH 7.4 and 38°C for 60 minutes of whole tissue homogenate (as source of phospholipids and phospholipases) with production of monolysocardiolipin (MLCL) and concurrent reduction of CL. In contrast, whole tissue homogenate of rat spleen treated similarly selectively deacylated ethanolamine plasmalogen (PE) producing lyso alkenyl PE.In the present study, we conducted in vitro incubation of whole tissue homogenate of guinea pig heart, kidney, testis and spleen at pH 7.4 and 38°C for 60 minutes. Subsequent TLC (thin layer chromatography) analysis revealed: a) a noticeable high level of MLCL and a very low level of CL in control testis, b) guinea pig heart and kidney revealed a high level of CL and no MLCL was detected. MLCL was only produced (in both heart and kidney) subsequent to in vitro incubation, c) very low level of CL was shown in control sample of guinea pig spleen and no MLCL was produced, d) guinea pig heart has both ethanolamine (PE) and choline plasmalogens (PC). PE plasmalogen is the only alkenyl species present in guinea pig kidney, testes and spleen.These data raised some questions pertaining to the lipolytic capabilities of diverse tissues and will be discussed in details.
Computational identification of novel peripheral protein‐membrane interactions
Authors: Kufareva Irina , Dancea Felician , Kiran Mahadev Ravi , Polonskaya Zinaida , Overduin Michael , Abagyan Ruben 
Published: June 2021

Soluble proteins are recruited to membranes in many cellular processes. The information about the ability of a protein to transiently interact with the bilayer often helps understanding its function. However, obtaining such information experimentally is costly and complicated.In this study, we present a fast computational method for detecting potential peripheral membrane proteins and their individual membrane‐inserting residues. The method relies on 3D structure alone and does not refer to homology with known membrane‐targeting modules. It is based on the analysis of protein surface curvature and statistical membrane propensities of the chemical groups.Using the method, we screened a set of 521 medium‐size protein domains with known X‐ray structures and residue chemical shift assignments. We identified four novel transient membrane binders: plant acetyltransferase AT1G, bacterial methionine sulfoxide reductase, human ARF‐1, and human von Willebrand factor. Bilayer interaction of these proteins was assessed by monitoring chemical shift changes in their 1H,15N HSQC spectra upon micelle addition. Based on the obtained per‐residue data, membrane docking position of each domain was determined by rigid‐body Monte Carlo optimization in a membrane/solvent boundary map. Analysis of the obtained positions proved the validity of our prediction.This work was supported by NIH grant 5‐R01‐GM071872‐02.