bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chitosan Oligosaccharide Ameliorates Kidney Injury by Improving Intestinal Barrier Dysfunction and Lipid Metabolism in Obese‐insulin Resistant Rats
Authors: Sutthasupha Prempree , Promsan Sasivimon , Phengpol Nichakorn , Pichyangkura Rath , Muanprasat Chatchai , Lungkaphin Anusorn 
Published: May 2022

IntroductionObesity remains a global health problem. High‐fat diet (HFD) consumption increases the risk of type 2 diabetes and initiates kidney injury. Chitosan Oligosaccharide (COS) provides anti‐obesity effects through several mechanisms. However, the effects of COS on preventing obesity‐related kidney injury in obese‐insulin resistance have not been studied. A novel action of COS in activating intestinal tight junction assembly was reported in in vitro via calcium sensing receptor‐mediated AMP‐activated protein kinase (CaSR/AMPK) activation. HFD‐induced gut dysbiosis is related with intestinal barrier dysfunction and systemic low‐grade inflammation. Therefore, AMPK activation might be a therapeutic target for preventing obesity‐related complications. Here, we explored the protective effects of COS in obesity‐induced kidney dysfunction and the involved molecular mechanisms. We hypothesized that COS might exert renoprotection against obesity‐induced kidney injury through increasing intestinal barrier integrity and lipid excretion.MethodsMale Wistar rats were fed with HFD for 16 weeks to induce obesity. Next, HFD rats were randomly divided into 4 groups: HFD, HFD treated with COS 5 or 10 mg/kg/day (COS5 or COS10) and HFD treated with metformin 30 mg/kg/day (MET). The interventions were orally treated for 8 weeks. At the end of experiment, blood, feces, intestinal and renal tissue samples were collected for further investigations.ResultsAfter 16 weeks of high‐fat diet feeding, obesity and glucose intolerance were presented in HFD compared to normal diet (ND) rats, as indicated by the significant increases in body weight (BW), plasma cholesterol and total area under the curve for glucose (TAUCg). Kidney injury were observed at week 24, as shown by elevated kidney injury score and serum creatinine. Treatment with COS5 or COS10 significantly decreased BW, hypercholesterolemia, glucose intolerance and kidney dysfunction. Interestingly, COS10 markedly increased fecal lipid excretion compared with HFD and MET. In addition, intestinal CaSR, p‐AMPK/AMPK and tight junction protein claudin‐1 expressions were downregulated in HFD which were upregulated by COS10 and MET. Renal TNFαR activation and increased proinflammatory cytokines were detected in HFD. Moreover, renal apoptosis markers, Bcl‐2‐associated X protein (Bax) and cleaved caspase‐3, were increased, along with the suppressing of anti‐apoptotic B‐cell lymphoma‐2 (Bcl‐2) in HFD. Treatment with COS10 or MET markedly alleviated renal inflammation and apoptosis.ConclusionCOS exerted renoprotection through attenuating renal inflammation and apoptosis as a result of improving intestinal barrier via CaSR/AMPK activation and lipid absorption in obese rats. Therefore, COS might be an effective new dietary supplement for treating obesity and its related complications in clinical use.
The E3 ubiquitin‐protein ligase Nedd4‐2 regulates the sodium chloride cotransporter (NCC) but is not required for a potassium‐induced reduction of NCC expression
Authors: Rosenbaek Lena , Petrillo Federica , Van Bemmelen Miguel , Staub Olivier , Murali Sathish , Fenton Robert 
Published: May 2022

Study objectiveThe activity of the sodium chloride cotransporter (NCC) in the kidney distal convoluted is important for kidney sodium (Na+) and potassium (K+) handling. NCC abundance is reduced by high plasms K+ levels. The E3 ubiquitin ligase neural precursor cell expressed developmentally downregulated 4‐2 (Nedd4‐2) is involved in regulation of NCC, but its precise role is unclear. The aim of this study was to examine the functional role of Nedd4‐2 on NCC regulation and whether Nedd4‐2 is involved in the high K+ effects on NCC.HypothesisNedd4‐2 regulates NCC membrane abundance by influencing NCC trafficking or degradation and plays an important role in the high K+ induced reduction in NCC.MethodsIn vitro studies were performed using tetracycline inducible MDCKI cell lines stably expressing human NCC combined with Nedd4‐2 knockdown using shRNA. The cell lines were characterized using immunoprecipitation coupled to biotin‐based membrane abundance assays. The effects of normal or high extracellular K+ on NCC in ex vivo isolated mouse kidney tubules from wildtype or Nedd4‐2 knockout (KO) mice were assessed.ResultsIn MDCK cells the levels of NCC and phosphorylated NCC (pNCC) were increased with Nedd4‐2 deletion, and NCC levels on the membrane were elevated. No significant changes were seen for the SPS1‐related proline/alanine‐rich serine‐threonine kinase (SPAK) and phosphorylated SPAK (pSPAK) after Nedd4‐2 knockdown. Deletion of Nedd4‐2 had no effect on the endocytosis rate of NCC, but NCC half‐life was increased. In tubules high K+ reduced total and pNCC regardless of genotype. The levels of the inwardly rectifying potassium channel subunits Kir4.1 and Kir5.1 were increased in Nedd4‐2 KO tubules. High K+ treatment decreased the level of Kir4.1, but not Kir5.1, only when Nedd4‐2 was eliminated. pSPAK was decreased with high K+ treatment regardless of the genotype.ConclusionNedd4‐2 is involved in ubiquitylation of NCC, regulation of NCC membrane abundance and degradation, but it does not play role in the K+ induced inhibition of NCC.
Engaging Students Equitably in Biological Systems Modeling
Authors: Anjur Sowmya 
Published: May 2022

It has been my goal as an educator to engage students in meaningful and innovative assessments that are hands‐on, engage their creativity and improve their interdisciplinary understanding. At the same time, the engagement need to be equitable as well, to recognize each student for their individuality and creativity. To this end, I created my Pathophysiology course with the objective of teaching students how to model biological systems. The course is a one semester course that is based on homeostasis maintenance in the body and how homeostatic disruptions result in symptoms of pathologies. Students are required to understand how homeostasis is maintained in individual organ systems and encouraged to model their understanding of homeostatic disruptions in ways other than biology, such as computer science and mathematics. This gives them an opportunity to use their creativity as well as apply their learning in other disciplines to create an interdisciplinary model of a biological system. Students have indicated that they appreciate being able to use their creative talents and non‐biological skills to model biological systems. Being able to use their non‐biological skills in a biology elective both encourages their problem solving skills and gives them confidence. Student learning is assessed through pre and post assessments and shows significant improvement in student understanding.Promoting equity in assessments has been challenging. There is a need to recognize the individual skills and learning patterns of each student and allow for this in creating assessments. I decided to replace two written assessments with hands on projects such as the heart model project and the graphic novels project. My purpose was to minimize memorization and promote integrative learning in a fun way. The heart model project replaced the cardiovascular system unit test. A variety of materials are provided to students for making life sized heart models, and instructor approval of student blueprints is required before beginning construction. Extra credit is offered if the model “works”. A second assessment, the graphic novel project, replaced student presentations and were much preferred by the students for the opportunities offered to demonstrate their drawing and creative skills. Every student felt included (as indicated on their surveys) and enjoyed the interdisciplinary integration of modeling in the course, an exercise in logical thinking that is applicable to any other discipline as well.
Oral Microbiota of Amazonian Kichwa Infants From Equador During the First Six Months of Life
Authors: Maldonado Lino Diana , Diaz Byron , Vanden Berghe Wim , Cevallos‐Cevallos Juan M. , Orellana‐Manzano* Andrea 
Published: May 2022

BackgroundFor public health policy, this study aimed to identify the oral microbiota in babies of the Amazonian Kichwa (AK) population of Ecuador born vaginally during the first six months of life.MethodThe study was descriptive, observational, cross‐sectional, where the bacterial communities of infants were analyzed. Twenty‐five infants self‐identified as AK were recruited from 2 rural areas (Ñucanchi‐Llacta and Pano) and one urban area (center of Tena) of Ecuador. Saliva samples were collected from the infants using the self‐collection kit. DNA was extracted from salivary samples, bacterial amplicons (16S) were generated and sequenced using Nanopore MinION, and the sequences were pre‐processed and data analyzed using EPI2ME.ResultsHigh bacterial diversity was observed in infants' saliva [2191 operational taxonomic units with 1% divergence]. Firmicutes and Proteobacteria were the predominant bacterial phyla present in all samples. A total of 10 bacterial genera were present in our data set. The predominant genera in infant saliva were Streptococcus, Staphylococcus, Bacillus, Gemella, and Veillonella.Conclusionour data show a rich bacterial community in the baby's oral cavity. The oral microbiota of the infants was relatively stable during the period studied and was very similar between them. Such similarity may result from maternal child care habits (e.g., kissing on the mouth). Further research is required to characterize the development of the oral microbiota early in life and identify environmental factors that affect colonization and the risk of oral and gastrointestinal diseases.
Homologues Phospholipases A2 isolated from Naja naja atra snake venom exhibit different activity against intact human erythrocytes
Authors: Cabrera Hernández Luis O. , Boyne Mascarell Juan , Maldonado Hernández Rafael , Quesada Orestes 
Published: May 2022

Phospholipases A2 (PLA2) catalyze the hydrolysis of fatty acid esters in the 2‐position of 3‐snphospholipids and are found in intracellular and secreted forms. Secretory PLA2s (sPLA2s) are small proteins (13‐15 kDa) classified into five groups based on primary structure differences. Despite their structural similarity, sPLA2s show a wide range of enzymatic and pharmacological activities. Most sPLA2s have high activity toward anionic membranes due to cationic residue presence on their binding recognition site (BRS). Within the same snake venom, several PLA2s can be found, which present differences in their ability to hydrolyze phospholipids in biological bilayers.In this study, Chinese cobra, Naja naja atra (N. n. atra) venom was purified by Size Exclusion Chromatography using a Superdex 75 and cation exchange using a column packed with Carboxymethyl Cellulose (CM‐Cellulose) to pre‐separate protein components from the venom. Subsequently, fractions displaying PLA2 activity were pooled, concentrated, and applied to a GE mini‐CM‐Cellulose column coupled to the AKTA Fast Protein Liquid Chromatography (FPLC) system. The final purification presents four peaks but only two present PLA2 activity (Band D and E). Peak purity was verified using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS PAGE).We have shown that hydrophobic residue presence on the PLA2 BRS is crucial for binding and hydrolytic activity toward human erythrocyte membranes. PLA2 activity was assayed against human erythrocytes and monomeric substrate to determine differences in hydrolytic activity. Primary sequence alignment shows 94% homology, however Band E presented 40% less activity against human erythrocytes, despite having 100% active site homology. Molecular modeling of both sPLA2s revealed differences at the Cys‐19 and Trp‐19 position and spatial orientation differences at the Trp‐61, Tyr‐63 Phe‐64, and Lys‐65 positions. Due to amino acid differences at the BRS, differences in hydrolytic activity may be linked to the anchorage of sPLA2 to the erythrocyte surface.
Location Bias Contributes to Functionally Selective Responses of Biased CXCR3 Agonists to Regulate Inflammation
Authors: Gardner Julia , Eiger Dylan , Boldizsar Noelia , Honeycutt Christopher C. , Kirchner Stephen , Hicks Chloe , Choi Issac , Zheng Kevin , Warman Anmol , Smith Jeffrey , Zhang Jennifer , Rajagopal Sudarshan 
Published: May 2022

G Protein‐Coupled Receptors (GPCRs) represent the largest and most diverse family of cell receptors in the human genome and are targeted by ~35% of all FDA‐approved drugs. GPCR signaling is mediated by various effectors, including G proteins, β‐arrestins, and GPCR kinases (GRKs). Recent studies have uncovered that different ligands can bind to the same GPCR and differentially activate specific signaling pathways, a phenomenon known as biased agonism. Most research has focused on characterizing biased agonism at the plasma membrane, but GPCRs are also known to traffic to and signal from a variety of subcellular compartments. To determine if GPCR subcellular localization contributes to biased signaling, we studied how the chemokine family GPCR CXCR3 signals from endosomes following stimulation by the three endogenous ligands CXCL9, CXCL10, and CXCL11.We determined that the biased ligands of CXCR3 promote different amounts of receptor mediated endocytosis and also show markedly different G protein and β‐arrestin signaling profiles at both the plasma membrane and the endosome. The biased activation of G proteins and β‐arrestins promotes differential activation of cytoplasmic and nuclear ERK1/2, as well as cellular transcription in both HEK293 cells and primary CD8+ T‐cells. Inhibition of receptor internalization greatly diminishes the biased signaling observed between the endogenous chemokines. Finally, we demonstrate in a murine model of contact hypersensitivity that receptor internalization is a key component of the ability of a synthetic β‐arrestin biased CXCR3 agonist to potentiate the inflammatory response. The present study shows the CXCR3 biased ligands induce unique signaling profiles at the plasma membrane and the endosome, and that signaling from endosomes greatly contributes to the overall biased responses seen at CXCR3. These results demonstrate that signaling from subcellar compartments is a critical component of GPCR signaling. Our findings have implications in the development of pharmaceutical drugs targeting chemokine receptors and other GPCRs.
Metabolic and Cardiac Manifestations in a Mouse Model of Genetic Mitochondrial Hepatopathy Without Obesity: Evidence for a Sexual Dimorphism
Authors: Burelle Charlotte , Deschênes Sonia , Cuillerier Alexanne , De Loof Marine , Higgins Marie‐Eve , Clavet Marie‐Elaine , Daneault Caroline , Sirois Martin , Burelle Yan , Ruiz Matthieu 
Published: May 2022

ObjectiveIn non‐alcoholic fatty liver disease (NAFLD), liver mitochondrial dysfunction plays an important role in the development of cardiac abnormalities independent of obesity per se. However, the mechanisms underlying the development of these abnormalities, and whether these are affected by sex remain unclear. In the present study, we sought to address this question using a mouse model of hepatic mitochondrial deficiency caused by loss of Lrpprc (H‐Lrpprc‐/‐) as these mice develop microvesicular steatosis and a NAFLD lipidomic‐like profile without obesity.HypothesisOur working hypothesis is that metabolic defects in the liver would trigger metabolic and functional abnormalities in the heart in a sex‐dependent manner.MethodsDetailed phenotyping experiments were performed in male and female H‐Lrpprc‐/‐mice and their controls at 14 weeks of age. Glucose metabolism was monitored by blood glucose as well as insulin, and glucose tolerance tests (ITT, OGTT). Cardiac manifestations were studied using molecular (qPCR), lipidomic (mass spectrometry) and functional (oximetry on isolated mitochondria, intraventricular pressures by Millar probe) analyses.ResultsGenetic inactivation of Lrpprc resulted in an >60% reduction of LRPPRC protein content in both males and females, which resulted in comparable structural liver abnormalities. In contrast, the resulting metabolic and cardiac functional changes displayed a marked sexual dimorphism. Lrpprc deficiency in the liver was associated with fasting hypoglycemia and increased insulin sensitivity in both sexes, but more so in males. Lrpprc deficiency was also associated with a remodeling of specific markers of mitochondrial function exclusively in the female myocardium. This included 1) reduced expression of gene markers for mitochondrial biogenesis (Tfam), fusion (Mfn1‐2), and fatty acid (FA) utilization and oxidation (Pparα, Cd36, Cpt1b, Cpt2, Vlcad, Lcad, Mcad), 2) impairment of FA‐dependent mitochondrial respiration, and 3) increased cardiac triglyceride levels. Paradoxically, cardiac function was preserved in females, while males displayed mild diastolic dysfunction as evidenced by increased early and late diastolic pressures (0.29 and 2.39 fold vs. male wild type respectively) amongst other parameters.ConclusionCollectively, these results indicate that metabolic defects in the liver can result in significant sex‐dependent abnormalities that affect both the mitochondrial/metabolic phenotype and contractile function independent of obesity. This experimental model may prove useful to better understand the mechanisms underlying the sex‐related variability in the progression of lean NAFLD in humans.
The impact of hydro‐dissection method in fascial plane delineation of dorsum of human hand
Authors: Kumar Madan 
Published: May 2022

In recent Ayurveda Anatomy education, hydro‐dissection method (HDM) has made technical advancements. It has been introduced as part of regular Ayurveda Anatomy lab. The author undertook investigation of dorsum of an embalmed human hand, using HDM, to visualise and analyse the intricacies of fascial components.Designing and assembling of the hydro‐dissection unit: An instrumentation is prepared, simulating the Sushruta Samhita mentioned method of dissection, for the concerned study. The instrument maintains an optimal standard for hydro‐dissection, monitoring and maintaining the temperature, slipstream, pH of the water and asepsis. The instrument also facilitates adequate visualization of the specimen without compromising the austerity of the procedure.Hydro‐dissection method and hydro‐dissection instruments: A blunt dissection is done using brushes and scrapers of various dimensions which help in segregation and differentiation of structures seen during HDM. Photos and videos along with textual documentation will be performed during the entire duration of each session. Identification and confirmation of the structures will be done by experts. Side‐by‐side comparison with existing atlases will be also done.The dorsal fascia of the hand is situated on the dorsal tendons of dorsal aspect of hand. The superficial fascia or the subcutaneous tissue is described as a layer of loose areolar tissue or adipose tissue. The difference in the thickness of fascia of palmar and dorsal hand is attributed to the difference in the range of mobility of structures passing through these areas. In this experiment, the author has tried to determine the relations in the transitional zones between the mid hand and the fingers by a layer‐by‐layer dissection. The superficial fascia is identified as a double layer of superficial fat and deeper fibrous tissue. It is separated from deeper layers by loose areolar tissue. The deep fascia becomes extremely thin distally. Usually, when the deep fascia becomes thin, it cannot be prepared as a continuous layer beyond the mid hand. As it passes distally, the fascia tends to blend with the superficial fascia. In the current scenario, the author has identified remarkable progress in the dissection, using HDM by delineating various planes of the fascia along with the resident and traversing structures.
Epitope Profiling Reveals the Antibody Immune Response Difference Between COVID‐19 Infected and Vaccinated
Authors: Pierson Lane M. , Yang Li , Liang Te , Fletcher Jesse , Lyon Christopher , Yu Xiaobo , Hu Tony 
Published: May 2022

Antibodies play an important part in combating SARS‐CoV‐2 infection whether generated by the infection or vaccination. However, the many epitopes generated by infection have not been fully investigated with only a few epitopes known and these being mostly limited to the S protein’s receptor binding domain (RBD) and the N‐terminal domain which limits vaccine and drug design 1‐4. The difference between epitopes generated by infection and vaccination has also not been studied. To address this, we employed a SARS‐CoV‐2 proteome microarray to screen for linear epitopes recognized by antibodies present in COVID‐19 patients and individuals vaccinated with the Pfizer‐BioNTech mRNA COVID‐19 Vaccine.The proteome microarray consisted of S, N, and E proteins, as well as spotting peptides that were 15 amino acids in length with overlaps of 5‐amino acids, covering the entire SARS‐CoV‐2 proteome (MN908947.3) (Figure 1). Blood samples were incubated onto the arrays followed by an incubation of fluorescent secondary anti‐human antibodies. Fluorescent intensity data generated and normalized using the Z‐score method and then further analyzed for significance by parametric one‐way ANOVA with Dunnett's post hoc test (COVID‐19 cohort) and repeated measure ANOVAs with Dunnett's post hoc tests (vaccinated cohort).The full‐length S protein showed a significant increase in COVID‐19 patients at around 20‐23 days after symptom onset and vaccinated individuals over all time points in both IgM and IgG antibodies (Figure 2A). Linear mapping of the IgM epitopes revealed a degree of overlap between infected and vaccinated individuals (22.2%; 6/27 total) with both having epitopes in the RBD and fusion peptide (FP) (Figure 2B). Structural mapping on 3D models of the S protein showed that all epitopes where on the surface of the protein and that COVID‐19 generated epitopes have a different pattern than those generated by vaccination (Figure 2C).An Epitope identified in this study with future prospects is epitope S481‐495 from COIVD‐19 patients that partially overlapped the binding site of two neutralizing antibodies previously isolated from COVID‐19 patients, S2H135 and F2B‐2F61, and contacted amino acids that interact with ACE2 receptor6,7. One epitope of note from the vaccinated individuals is epitope S811‐825 which mapped adjacent to the fusion‐peptide proximal region. These epitopes may be helpful in future vaccine and antibody therapy development.1 Ju, B. et al. Nature 584, 115‐119.2 Robbiani, D. F. et al. Nature 584, 437‐442.3 Seydoux, E. et al. bioRxiv.4 Wu, Y. et al. Science 368, 1274‐1278.5 Piccoli, L. et al. Cell 183, 1024‐1042 e1021.6 Casalino, L. et al. ACS Cent Sci 6, 1722‐1734.7 Wang, Q. et al. Cell 181, 894‐904 e899.