bluuebunny/crossref_metadata_2025_split huggingface dataset:
Foundations for a lifetime: A qualitative inquiry into the salient aspects of cadaver dissection over time and their impact on medical professionals
Authors: Skinner Miki D , Morrow Sue , Morton David A 
Published: June 2021

Cadaver dissection has been a central part of the education of medical professionals for centuries. Throughout that time, anatomists have claimed that dissection is a learning experience rich with life lessons encompassing more than simply gross anatomy. Yet, no published empirical data exists of the long‐term impact that dissection has on medical professionals. The objective of the current study was to explore the aspects of cadaver dissection that remain salient following the transition from medical student to medical professional. This qualitative research utilized grounded theory methodology exploring the autobiographical narratives of physicians (n=36) 5 to 57 years post‐graduation. Data were drawn from multiple sources: interviews, written reflections, focus group, and archival data. Results indicate that physicians reflect on their dissection experience as a foundation for skills in teamwork, deportment with patients, and diagnostic visualization among others. Implications of these results add to the pedagogical value of dissection, providing empirical evidence for the multi‐faceted learning within the anatomy laboratory. The study was funded in part by the Frank L. Christensen Fellowship.Grant Funding Source : Frank L. Christensen Fellowship
Increased stress during gross anatomy course negatively affects students’ performance
Authors: Ramos Amanda , Bringe Kariline 
Published: June 2021

A modular design of gross anatomy curriculum encompasses learning a large amount of content in a short time frame. Studies have identified academic responsibilities as a stressor which may negatively impact students’ comprehension of material. At Mayo Medical School, the academic demands of the 7 week anatomy course provide an environment that may predispose students to increased stress. Our research explores the relationship between perceived stress and academic performance. A validated survey instrument identified a baseline stress level prior to the course and was used to reassess at timed intervals during the course. Stress levels were compared to course performance using quiz and laboratory practical grades as performance indicators. Preliminary results demonstrated a 46% increase in perceived stress levels (10.8 to 15.8) by day 21 with an increasing correlation between perceived stress and decreased academic performance. From day 7 to day 21, the correlation between perceived stress and quiz scores increased from R2=0.0002 to 0.29. The correlation between stress and laboratory practical grades increased from R2=0.09 to 0.29. Understanding the impact of stress on academic performance may aid in helping students with high perceived stress develop coping strategies which may increase performance as well as retention of anatomical knowledge.Grant Funding Source : Department of Anatomy, Mayo Clinic College of Medicine
Hydrogen sulfide reduces GFP‐tagged autophagosomes in vitro
Authors: Duarte Maria J , Julian David , Akin Debra , Dunn William A , Wohlgemuth Stephanie E 
Published: June 2021

Autophagy, a process by which intracellular components are degraded within lysosomes, has been implicated in protection from ischemia/reperfusion (I/R) injury. The gasotransmitter H2S has also been associated with I/R protection. H2S activates the PI3‐Kinase/AKT pathway. However, activation of this pathway has been shown to inhibit autophagy.ObjectiveTo test whether H2S exposure attenuates autophagy.MethodsSaos‐2 human osteosarcoma cells, stably expressing the autophagosome (AP) marker GFP‐LC3, were placed in Krebs‐Henseleit Buffer (“starved” cells), which induces autophagy, or in growth medium (“fed” cells) for 4 h. H2S gas was then added to a final concentrations of 1, 10, or 100 ppm for 1 h. The number of GFP‐tagged APs per cell was quantified using epifluorescence microscopy.ResultsAddition of H2S significantly reduced the number of GFP‐tagged APs per cell in starved cells from 4.1 ± 0.9 (SE) to 2.0 ± 0.5, and in fed cells from 1.8 ± 0.3 to 1.1 ± 0.1 (H2S‐effect: p = 0.016). The effect of H2S on autophagy was similar at 1, 10 and 100 ppm, with the lowest H2S concentration producing sub‐micromolar dissolved H2S. Addition of H2S did not reduce fluorescence intensity per AP or the fluorescence of cytosolic GFP, suggesting that H2S did not have a direct effect on GFP fluorescence. These data suggest that the role of H2S as a protective agent in I/R injury is likely independent of autophagy. Supported by UF funds to SEW.
Nuclear Translocation of Phosphorylated Akt is Critical in Ellipticine‐Induced Apoptosis in Human Lung Epithelial Cancer Cells A549
Authors: Fang Kang , Wang Jing-Ping , Liang Huan-Chang , Yu Ya-Chu , Lin Kai-Han 
Published: June 2021

Topoisomerase II inhibitor ellipticine and its analogues were reported as promising antitumor agents. We have reported previously that ellipticine induced nuclear translocation of p53 and Akt followed by autophagic apoptosis in human non‐small cell lung cancer cells A549. The effect can be reverted by autophagy inhibitors. In this work, we further demonstrated that transfection of p53 siRNA suppressed ellipticine‐induced apoptosis by blocking Akt nuclear translocation. In addition, introduction of either point‐mutated Akt473 or Akt308 inhibited p53 translocation as indicated by confocal microscopy and western blotting. On the other hand, in p53‐null H1299 cells with stably expressed wild type p53, cells become sensitive to ellipticine treatment accompanied with nucleus translocation of p53 and Akt. In addition, as cells were pretreated with autophagy inhibitor before being treated with ellipticine, Akt phosphorylation was suppressed with decreased apoptotic cell death. We concluded nuclear translocation of phosphorylated Akt is essential in leading to ellipticine‐induced cell death in human non‐small cell lung cancer cells.The work is supported by grants from the National Science Council, Taiwan (NSC100‐2311‐B‐003‐003) and National Taiwan Normal University (99‐D3)
Dynamic regulation of lipid droplets in the microalgae Chlamydomonas reinhardtii
Authors: TSAI CHIA-HONG , Benning Christoph 
Published: June 2021

Under nitrogen deprivation the microalgae Chlamydomonas reinhardtii stores triacylglycerols (TAGs) in the lipid droplets. Upon resupply with nitrogen, TAGs are metabolized to generate energy and membrane building blocks needed by the cell. To understand how the lipid droplets remain intact in the presence of lipases and to determine factors required for the transition from lipogenesis to lipolysis, antibodies against the most abundant perilipin‐type protein in the Chlamydomonas lipid droplet (MLDP) were produced. Using these antibodies we were able to demonstrate the phosphorylation of MLDP and the possible recruitment of different sets of proteins to lipid droplets during lipogenesis and lipolysis. We also applied an antibody‐based dot‐blot technique to screen for the mutants unable to hydrolyze TAGs during lipolysis. One of the compromised‐hydrolysis‐of‐TAG mutants, cht7 showed 10‐fold higher TAG levels than the wild type after the induction of lipolysis. In addition, cell growth of cht7 under this condition was strongly delayed. The mutant phenotype suggests a direct coupling of lipolysis with cell cycle progression. Likely candidate genes responsible for the phenotype in this mutant were identified.This research is sponsored by United States Air Force Office of Scientific Research.
Biological features of human catalytic antibody light chains showing anti‐cancer activity
Authors: Uda Taizo , Hifumi Emi 
Published: June 2021

The authors have reported about the human catalytic antibody light chains possessing catalytic activity, which was mostly encoded in Subgroup II in kappa type. In this study, the highly purified human light chains were submitted to investigate the function of the toxicity against cancer cells.We designed two primer sets and performed a semi‐nested PCR using cDNA prepared from human leukocyte. As the results, eighteen clones of subgroup II germline gene of human kappa light chain were established. The mutants of C220A corresponding to the 18 clones were made. And the wild types and mutants were expressed in E. coli and the light chains recovered were highly purified by two‐step purification system. Out of 18 clones, #1 clone showed the cytotoxicity to both human lung (A548) and human stomach cancer cells (SNU‐1) but not to pancreas cancer cells (PANC‐1). Interestingly, the dimeric form showed the stronger effect than the monomeric form (C220A). The #1 clone could hydrolyze QAR‐MCA synthetic peptide showing the amidase activity. In addition, #1 clone has a unique amino acid sequence compared with that of other clones. Although it is still unclear that the relationship between catalytic activity and cytotoxicity of human light chain (#1 clone) at this moment, the catalytic triad structure of the clone may contribute the anti‐cancer effect.
Maternal fucosyltransferase 2 genotype alters milk immunoglobulin A levels specific to some strains of norovirus
Authors: Taft Diana Hazard , Jiang Jason , Huang Peng-Wei , Davidson Barbara , Morrow Ardythe Luxion 
Published: June 2021

Secretory immunoglobulin A (sIgA) found in mother's milk reflects her immune response to a lifetime of infectious challenge and helps protect infants from many infectious diseases, including noroviruses (NVs). Some NV strains preferentially infect secretors (Se) ‐ individuals with a functional copy of the fucosyltransferase 2 (FUT2) gene, those lacking a functional copy are non‐secretors (Non‐Se). We tested the hypothesis that maternal secretor status alters the levels of strain‐specific NV antibodies in milk. We analyzed the relative levels of milk sIgA against two strains of NV ‐ strain 387, which preferentially infects Se, and strain 207 which does not preferentially infect Se individuals. Strain‐specific and total sIgA were analyzed using ELISA in week 4 milk samples from 79 mothers. Maternal FUT2 genotype was analyzed by TaqMan assay to identify the 428G>A null mutation. The relationship between maternal secretor status and total, anti‐387, and anti‐207 sIgA was analyzed using Kruskal‐Wallis tests with Bonferroni correction. Non‐Se mothers had significantly lower levels of anti‐387 sIgA (p<0.001) in their milk. There were no significant differences in the amount of total or anti‐207 sIgA levels in milk based on maternal FUT2 genotype. This study indicates that milk sIgA levels can be influenced by genetics as well as history of infection.Grant Funding Source: NICHD P01 HD 13021
Uptake and metabolism of α‐mangostin by human cell lines: HepG2 liver cells, HT‐29 colon cells, and THP‐1 macrophage‐like cells
Authors: Orozco Fabiola Gutierrez , Chitchumroonchokchai Chureeporn , Riedl Kenneh M , Schwartz Steven J 
Published: June 2021

Xanthones present in the pericarp of mangosteen fruit (Garcinia mangostana L.) possess a distinct isoprenylated tricyclic structure and have been reported to exhibit anti‐inflammatory and anti‐proliferative/ pro‐apoptotic activities. However, information on the absorption, metabolism and in vivo efficacy of xanthones remains elusive. Recent results from our lab show that ingested xanthones and their phase 2 metabolites are present in several tissues of mice. This study investigated the uptake and metabolism of α‐mangostin (α‐MG) by human liver, colon, and macrophage‐like cell lines. Free and conjugated (glucuronidated/sulfated) α–MG were analyzed by RP‐HPLC. Our results suggest that degree of uptake, metabolism and intracellular retention of α–MG is dependent on cell type. HepG2 readily accumulated free α–MG in cells. The conjugated α–MG was the majority detected in HT‐29 cells. α–MG content in THP‐1 cells was low and conjugates were predominant. Conversion of α–MG to other xanthones also was observed. LC‐MS‐MS analysis confirmed γ‐MG and 9‐ hydroxycalabaxanthone in HepG2 medium and cells. Other xanthones present in HepG2 and HT‐29 cells remain to be identified. These data suggest cell‐specific metabolism of α–MG. Mass spectrometric analysis and study of anti‐inflammatory activity of α–MG and metabolites are ongoing.Grant Funding Source : OSU Food Innovation Center, Nutrient and Phytochemical Analytic Shared Resource and Conacyt Fellowship (Mexico)
Analysis of study length truncation in vitamin A compartmental analysis in human and rats
Authors: Gannon Bryan M , Howe Julie A , Green Michael H , Tanumihardjo Sherry A 
Published: June 2021

Previous studies indicate that isotope dilution tests may not fully reveal total body vitamin A reserves, due to lack of time for dose to fully equilibrate with body stores. A healthy female was given an oral dose of 13C4‐retinyl acetate (17.5 umol), and blood samples were taken at baseline and over the course of 6 years. Serum retinol was analyzed for 13C/12C ratio by GC‐C‐IRMS, indicating fraction of dose in the plasma. Fraction of dose data are mathematically modeled using compartmental analysis. Different models were created to simulate a range of study‐lengths and total body reserves (TBR) and other kinetic parameters were calculated for each model. As length of study was increased, TBR was found to increase until it reached a maximum at around 500 days. Disposal rate was found to decrease as length of study increased until it reached a minimum at around 500 days. In agreement with non‐modeled isotope dilution, assumed absorption of dose is directly proportional to amount of total stores, indicating that even with compartmental analysis, accurate assessment of absorption is necessary for proper modeling and TBR calculation. To verify these conclusions with a larger sample size, data from an isotope dilution study in rats is being treated to a similar truncation of study length. These results indicate that there are slower turning over pools of vitamin A that would not be detected with a shorter study length.Grant Funding Source : NIH‐NIDDK 61973
VEGF induces RANKL in Rheumatoid Arthritis synovial fibroblasts
Authors: Kim Kyoung-Woon , Kim Hae-Rim , Kim Bo-Mi , Cho Mi-La , Lee Sang-Heon 
Published: June 2021

BACKGROUDVEGF is the most endothelial cell‐specific angiogenic factor characterised to date. Several recent reports have demonstrated that VEGF is also implicated in the pathogenesis of RA, and serum levels of VEGF correlate well with RA disease activity, particularly with swollen joint counts.OBJECTIVEThis study aims to determine the effect and mechanism of VEGF on bony destructive process in RA through RANKL regulation from synovial fibroblasts.METHODSynovial fibroblasts were isolated from synovial tissues of RA patients. After RA synovial fibroblasts were treated with rhVEGF, the expression of RANKL mRNA was determined using real‐time PCR. After inhibition of pro‐inflammatory cytokines or intracellular signal molecules, the change of the VEGF‐induced RANKL expression was determined using real‐time PCR.RESULTSThe expression of RANKL mRNA in RA synovial fibroblasts was increased after VEGF stimulation in a dose dependent manner. VEGF‐induced RANKL expression was also diminished after inhibition of Src, PKC and ERK.CONCLUSIONOur results show that VEGF upregulates RANKL expression in RA synovial fibroblasts. These effects are mediated by the Src/PKC and ERK pathways.This work was supported by the National Research Foundation of Korea Grant funded by the Korean Government (NRF‐2010‐R1A4A007‐0024198)
Ventral and Dorsal Hippocampus of rats similarly modulate autonomic responses evoked by restraint stress
Authors: Scopinho América Augusto , Lisboa Sabrina F , Corrêa Fernando M.A. , Guimarães Francisco S , Resstel Leonardo B.M. , Joca Sâmia R.L. 
Published: June 2021

IntroductionThe hippocampus is a brain structure divided into dorsal (DH) and ventral (VH) portions. Stimulation of these areas evokes autonomic changes. During restrain stress (RS) hippocampus neurons are activated, besides causing hormonal changes and autonomic responses such as increased heart rate (HR) mean arterial pressure (MAP) and reduction of tail temperature. Thus, the aim of our study was to investigate the involvement of VH and DH on the autonomic responses, caused by the RS.MethodsMicroinjections of CoCl2 (cobalt chloride; 1mM/ 500nL) or vehicle in the VH or DH of Male Wistar were made. Ten minutes after the microinjection of drugs, the animals were submitted to the RS for an hour. During RS cardiovascular parameters and skin temperature were registered.ResultsThe injections of CoCl2 into the VH (n=6) significantly reduced the increase of both MAP (F1,480=449.5; P < 0.001) and HR (F1,480 = 429.8, P<0.0001) and temperature decreases (F1,144 = 273.2, P<0.0001) evoked by RS, when compared to the control animals (n=4). In the same way, the bilateral microinjections of CoCl2 in DH (n=7) reduced the increase of both MAP (F1,165= 211, P<0.05) and HR (F1,165= 161, P<0.05) and temperature decreases (F1,165= 164, P<0.05) when compared to the control animals (n=6).ConclusionThese results suggest that show that VH and DH similarly modulate autonomic responses to RS.Financial Support: CAPES and FAPESP.
Genotoxic Stress Results in Selective P‐body Formation in S. cerevisiae
Authors: Segal Scott P. , Rathmann Blaine , Koch Anthony , Sutter Chad , Michelson Cara , Wilson Ted 
Published: June 2021

Survival mechanisms to cope with oxidative stress are conserved across all eukaryotes. However, our understanding of these mechanisms at the level of DNA and mRNA is poorly understood. Exposure to oxidizing agents can result in damage to lipids and nucleic acids, and can illicit a stress response. The genotoxic agent sodium dichromate oxidizes guanines resulting in formation of OxoG bases, or causes double strand breaks. In contrast, peroxides, allow for strong oxidation of lipids and nucleic acids.Control of translation may play a role as part of the DNA oxidative stress response. Upon exposing yeast to sodium dichromate, we saw a selective increase in P‐bodies, with a treatment as low as 15 uM, whereas stress granules fail to form. P‐bodies and stress granules are cytoplasmic structures in which non‐translating mRNA are found. Whereas P‐bodies contain RNA degradation factors, stress granules contain translation initiation factors. This suggests that stress granules contain stored RNA poised for translation. Moreover, the response occurs within 10 minutes of exposure, suggesting a model in which either damaged mRNA or mRNA transcribed from damaged genes is selectively degraded rather than stored. Currently, we are determining whether a co‐treatment with anti‐oxidants can abrogate this effect. This study provides novel insights into how yeast and perhaps other higher eukaryotic cells respond to DNA oxidation.
Blood brain barrier KCa3.1 channels: evidence for a role in brain Na uptake and edema during ischemic stroke
Authors: Chen Yi-Je (Jay) , Yuen Natalie , Wallace Breanna K , Wulff Heike , O'Donnell Martha E 
Published: June 2021

Our previous studies provided evidence that ischemia induces cerebral edema in part by stimulating activity of a luminal blood brain barrier (BBB) Na‐K‐Cl cotransporter (NKCC), leading to increased secretion of Na, Cl and water from blood into brain through functional coupling of NKCC with abluminal Na/K pump and Cl channels. K channels support NaCl transport across other epithelia by maintaining membrane potential, allowing continued Cl efflux via Cl channels. However, little is known about BBB K channels. In the present study we have identified the presence of the calcium‐activated KCa3.1 channel on cultured bovine cerebral microvascular endothelial cells (CMEC) by patch‐clamp, Western blot and immunocytochemical staining methods. Using radioisotopic flux methods and the KCa3.1‐specific blocker TRAM‐34, we also found a dose‐dependent TRAM‐34 inhibition of K+ flux in the CMEC. Further, we found that the CMEC TRAM‐34‐sensitive K+ flux was stimulated by oxygen‐glucose deprivation. Finally, in magnetic resonance (MR) Na spectroscopy and MR imaging in vivo studies we found that middle cerebral artery occlusion‐induced rat brain Na uptake and edema were significantly attenuated by TRAM‐34 (40 mg/kg IP). Our findings suggest that KCa3.1 blockade constitutes an attractive approach for reducing cerebral edema formation in the early stages of ischemic stroke or during brain surgery.Supported by AHA & NIH
Role of CFTR and sphingolipids in hypoxic pulmonary vasoconstriction
Authors: Yu Hanpo , Wang Liming , Kapus Andras , Kuebler Wolfgang M. 
Published: June 2021

BackgroundHypoxic pulmonary vasoconstriction (HPV) optimizes ventilation‐perfusion matching in the lung. As cystic fibrosis patients suffer from ventilation‐perfusion mismatches, we probed for a potential role of cystic fibrosis transmembrane conductance regulator (CFTR) in HPV.MethodsHPV was quantified in isolated lungs as increase in perfusion pressure in response to hypoxia. In cultured human pulmonary artery smooth muscle cells (PASMC), Ca2+ concentration ([Ca2+]i) was imaged, and caveolae were isolated and probed for translocated Ca2+ entry channels.ResultsHPV was attenuated by CFTR inhibitors or in lungs of CFTR−/− mice. In PASMC, CFTR inhibition blocked the hypoxia‐induced [Ca2+ ]i increase and the caveolar translocation of TRPC6 channels. CFTR's role in HPV was not attributable to Cl− transport, as modulation of extracellular Cl− did not alter HPV. Instead, the role of CFTR was related to sphingolipid signaling in HPV. In isolated lungs, inhibition of either neutral sphingomyelinase (SMase) or sphingosine kinase attenuated HPV. Exogenous SMase mimicked hypoxia, in that it caused pulmonary vasoconstriction, increased PASMC [Ca2+]i, and translocated TRPC6 to caveolae, yet responses to SMase were blocked by CFTR inhibition.ConclusionOur findings identify a critical role for CFTR in HPV that relates to sphingolipid signaling by a mechanism currently under investigation.
The effects of oxytocin on gastric motility are mediated by different neuronal pathways in an iodoacetamide model of functional dyspepsia
Authors: Holmes Gregory M , Travagli R. Alberto 
Published: June 2021

Emotional stress triggers functional dyspepsia (FD) and gastric dysmotility. Oxytocin (OXY) has a recognized antistressor role and OXY microinjection in the dorsal vagal complex induces gastric relaxation via a vagally‐mediated pathway. Our in vitro data (see abs. by Babic et al.) show that FD induces a plastic rearrangement in the gastric‐related vagal circuits so that OXY perfusion modulates the otherways unresponsive GABAergic inputs to gastric‐projecting preganglionic vagal (DMV) neurons.The aim of the present study was to investigate the in vivo mechanisms of action of OXY in a FD model.Following induction of FD, we monitored the gastric motility response induced by DMV microinjection of OXY (12.5–300pmoles). In control rats, the OXY‐mediated decrease in gastric tone peaked at a dose of 300pmoles and was antagonized by systemic administration of the NOS inhibitor, L‐NAME, which per se did not alter gastric tone. In FD rats, the dose‐response to OXY‐mediated decrease in gastric tone was shifted leftward, L‐NAME increased gastric tone and did not attenuate the OXY response.These data show that in control rats, the gastric relaxation induced by OXY is mediated by activation of a NANC vagal pathway. Following FD induction, the gastric relaxation mediated by OXY is no longer mediated by activation of a NANC pathway, but rather by inhibition of a vagal cholinergic input.Funding: NIDDK 55530