bluuebunny/crossref_metadata_2025_split huggingface dataset:
ED‐1 is a marker for activated macrophages and subclinical graft versus host disease in vascularized stem cell transplants
Authors: Brown Russell , Lefebvre Daniel , Tai Chai , Matthews Martha , Strande Louise , Eydelman Riva , Hewitt Charles W. 
Published: June 2021

Acute and chronic graft‐versus‐host disease (GVHD) is a major complication of bone marrow transplantation (BMT). Overt histopathological findings of GVHD are well documented. However, histopathology of subclinical GVHD is uncertain. We are studying a new type of BMT that can facilitate tolerance induction without GVHD. We hypothesized that subclinical GVHD may be induced. The model is known as a vascularized bone marrow transplant (VBMT).Lewis‐Brown‐Norway (LBN) rats radiation. Rats then received either a cellular (cBMT, n=5) or VBMT (n=4). After 110 days, splenic histopathology was assessed by H&E staining and digital image analysis.Then splenic specimens were studied using Immunohistochemical staining for ED‐1 macrophage cell surface antigen.Digital image analysis revealed very little hemosiderin present in the control spleens (mean ISI 0.86) and a large amount of hemosiderin in the cBMT spleens (mean ISI 11.75). The VBMT had an intermediate level of hemosiderin (mean ISI 8.27). All groups were significantly different (p<0.05). Qualitatively, it was noted that increased amounts of ED‐1 positive macrophages were present in cBMT spleens and VBMT spleens undergoing subclinical GVHD, compared to normal spleens.Hemosiderin laden and activated macrophages may represent markers for sub‐clinical GVHD due to red blood cell destruction through opsonization associated with graft versus host disease.
Role of mitochondria in flow‐induced dilation of human adipose arterioles from subjects with and without coronary artery disease
Authors: Zinkevich Natalya Sergeevna , Wittenburg April L , Gutterman David D 
Published: June 2021

BackgroundFlow‐induced dilation (FID) is an important physiological stimulus in regulating tissue blood flow. FID is typically mediated by endogenous vasodilators including nitric oxide (NO) and prostacyclin. In humans with coronary artery disease (CAD), FID occurs but is not mediated by NO; rather hydrogen peroxide (H2O2) is responsible. In the coronary circulation H2O2 derives from the mitochondria, but it is not known if this is a generalized process that also involves adipose arterioles. We examined the hypothesis that the mitochondrial electron transport chain critically contributes to FID in human adipose arterioles.MethodsVisceral adipose arterioles (~150 μm ID) obtained at surgery from patients with or without CAD were cannulated and pressurized (60 mmHg) for videomicroscopy. After constriction with endothelin‐1, vasomotor responses to flow were evaluated in the presence and absence of the rotenone (1microM), a mitochondrial complex I inhibitor. At the end of each experiment, papaverine (0.1 mM) was added to obtain the maximal arteriolar diameter and assess non‐specific effects of rotenone.ResultsFID was reduced by rotenone in adipose arterioles from patients with CAD (%max dilation: 33±10 vs. 73±10%). In contrast, rotenone had no effect on FID arterioles from patients without CAD (%max dilation: 61±9 vs. 65±6%) or on the dilation to papaverine in either group.ConclusionsWe speculate that in patients with but not in those without CAD FID requires an intact proximal mitochondrial electron transport. This is a general response seen in multiple vascular beds.
High Salt Exacerbates Proteinuria in Chronic Angiotensin‐II Infused Rats.
Authors: Lowenburg Benjamin M , Planchard Jeffrey A , Martin Victoria L , Davis Porcha D , Botros Fady T , Mitchell Kenneth D , Navar L Gabriel , Prieto Minolfa C 
Published: June 2021

This study examined the effect of a high salt (HS) diet on systolic blood pressure (SBP) and proteinuria in chronic Ang II‐infused hypertensive rats with and without RAS blockade with an Ang II type I receptor blocker, losartan (LOS). Male Sprague‐Dawley rats divided into four groups: 1) Sham+HS [n=5]; 2) Ang II [n=3]; 3) AngII+HS [n=5]; 4) Ang II+HS+LOS [n=5] were infused with Ang II (80 ng/min) for 14 days, fed with HS diet (8% NaCl) and treated with LOS (30 mg/L, drinking water). SBP progressively increased in Ang II and Ang II+HS rats up to 228±9mmHg and 228±10mmHg, respectively, compared to Sham+HS (128±7mmHg). Losartan attenuated the increases in SBP during the two‐weeks of treatment (144±9mmHg). Rats receiving Ang II+HS showed marked proteinuria measured in 24h‐urine collections (79±26mg/day) which was greater than in the Ang II group. Proteinuria decreased in the Ang II+HS+LOS, but not to levels of Sham+HS (29±2mg/day vs. 18±1mg/day), indicating a partial beneficial effect of LOS on proteinuria. The lack of difference between SBP in rats with Ang II‐induced hypertension and those that also received HS suggest that HS does not exert an additive effect on SBP. However, the presence of marked proteinuria in Ang II+HS rats indicates that HS might contribute to glomerular kidney damage independently of SBP and Ang II effects suggesting a direct action on glomerular protein barrier.Support from NIH and Merck & Co., Inc.
Impaired pressure‐natriuresis relationship precedes the development of hypertension in Cyp1a1‐Ren‐2 transgenic rats
Authors: Cervenka Ludek , Thumová Monika , Husková Zuzana , Vanecková Ivana 
Published: June 2021

ObjectiveThe present study was performed to characterize the autoregulatory efficiency of renal blood flow (RBF) and glomerular filtration rate (GFR) and the pressure‐natriuresis relationship in transgenic rats with inducible hypertension (Cyp1a1‐Ren‐2 rats).MethodsThe renin gene was induced in Cyp1a1‐Ren‐2 rats trough dietary administration of the natural xenobiotic indole‐3‐carbinol (I3C, 0.3 %) for 12 hours. Non‐induced rats served as controls. Anesthetized rats were prepared for renal function studies and an aortic clamp was placed on the aorta to regulate the level of renal arterial pressure. ANG II levels were measured by radioimmunoassay.ResultsAdministration of I3C resulted in progressive increases in ANG II levels as compared with non‐induced rats. I3C‐induction for 12 hours did not cause significant changes in blood pressure as compared with non‐induced rats. 12 hours I3C‐induction caused an impairment of the autoregulatory efficiency of RBF and GFR and of the pressure‐natriuresis relationship as compared with non‐induced rats.ConclusionsOur findings indicate that an impairment of the pressure‐natriuresis mechanism precedes the development of ANG II‐dependent hypertension in Cyp1a1‐Ren‐2 transgenic rats.
Role of the lateral prefrontal cortex in cardiovascular responses to acute restraint in rats
Authors: Alves Fernando Henrique Ferrari , Crestani Carlos Cesar , Corrêa Fernando Morgan de Aguiar 
Published: June 2021

ObjectivePrevious works have demonstrated the participation of the lateral prefrontal cortex (LPC) in cardiovascular modulation in stress situations. However, these works was made which lesions or microinjection of the lidocaine, which are non selective methods that blockade or destroyed both, passenger fibres and synapses. To investigate the real participation of (LPC) in the cardiovascular modulation we used CoCl2 that is selectively blocks synapses. Thus the aim of present work was to study the participation of LPC in the modulation of cardiovascular system during acute stress.MethodsMale Wistar rats had guide cannulas bilaterally implanted in the LPC. One catheter was implanted in the femoral artery for mean arterial pressure (MAP) and heart rate (HR) recording. Acute stress was induced by putting animals in a small plastic cylindrical restraining tube during 60 min.ResultsMicroinjection of cobalt in the LPC caused no changes in MAP or HR, which were 100±1 mmHg and 352±11 bpm, n=6. Cobalt treatment significantly decrease response to restraint‐evoked HR and BP, when compared with aCSF‐treated animals (ΔMAP, F=1.3, P=0.03 and ΔHR, F=2.1, P<0.000; two‐way ANOVA.ConclusionOur data indicate that LPC is involved in the modulation of the cardiovascular system during acute stress.Financial supportFAEPA, CNPq
Regulation of the intestinal mucin MUC2 expression by short chain fatty acids: implications for epithelial protection
Authors: Burger‐van Paassen Nanda , Vincent Audrey , Puiman Patrycja J , van der Sluis Maria , Bouma Janneke , Boehm Gunther , Van Goudoever Johannes B , Van Seuningen Isabelle , Renes Ingrid B 
Published: June 2021

Short chain fatty acids (SCFAs) influence epithelial‐specific gene expression. We hypothesize that SCFAs affect mucin MUC2 expression and thereby epithelial protection. Aim: Study the effects of SCFAs on MUC2 expression.MethodsLS174T cells were treated with SCFAs. MUC2 mRNA levels and stability and MUC2 protein expression were analyzed. SCFA‐responsive regions and cis‐elements within the MUC2 promoter were identified by transfection and gel shift assays. Effects on histone H3/H4 status at the MUC2 promoter were established by chromatin immunoprecipitation.ResultsBoth 1 mM butyrate and propionate induced an increase in MUC2 mRNA levels. MUC2 mRNA levels returned to basal levels after incubation with 5‐15 mM of butyrate. This decrease was not due to loss of RNA stability. At 5‐15 mM of propionate MUC2 mRNA levels remained high. Promoter regulation studies revealed a butyrate‐responsive region in the MUC2 promoter containing an active AP1 cis‐element at ‐818/‐808 that mediates butyrate‐induced activation of the promoter. MUC2 regulation by butyrate at 10‐15 mM was associated with increased acetylation of histone H3/H4 and methylation of H3 at the promoter.Conclusion1 mM of butyrate and 1‐15 mM of propionate increase MUC2 expression. The effects of butyrate on MUC2 mRNA are mediated via AP‐1 and acetylation/methylation of histones. Thus SCFAs affect MUC2 expression and thereby intestinal protection.
From birth to adulthood in a nutshell : hematopoietic stem cell development in vitro & HOXB4
Authors: Klump Hannes , Lesinski Dietrich , Heinz Niels , Rainer Loew , Pilat Sandra , Carotta Sebastian , Beug Hartmut , Schiedlmeier Bernhard , Baum Christopher 
Published: June 2021

Ectopic expression of the homeodomain transcription factor HOXB4 has been shown to enhance the in vivo repopulation ability of in vitro differentiated mouse ES‐cells. How it promotes the conversion of ES‐cells to HSCs is not yet known. Here we demonstrate that its expression enforces the development of the developmentally earliest known hematopoietic cell during ES‐cell differentiation and promotes its expansion in stroma‐cell free suspension cultures. As these cultures lead to long‐term engraftment after transplantation into Rag2(‐/‐)γ(‐/‐) mice, the ability to engraft may correlate with the presence of these earliest, CD41hi cells. To test whether the CD41+ subpopulation depends on expression levels of HOXB4, we designed new tetracycline regulatable cassettes in which all necessary components were embedded in a single retroviral vector.The presence of a CD41hi / c‐Kit+/− / CD45− subpopulation correlated with HOXB4 expression levels in clonal ES‐HC cultures. This subpopulation was capable of reconstituting the entire heterogeneity of the primary suspension culture and differentiated towards all lineages in colony assays.In summary, we show that HOXB4 expression enhances the in vitro generation and expansion of the earliest known HSCs from mouse ES‐cells. Its tight and fine‐tuned regulation may also support the generation and safe expansion of patient‐specific pluripotent stem cell derived HSCs.
6S RNA Regulation of Transcription
Authors: Wassarman Karen M , Klocko Andrew D , Cavanagh Amy 
Published: June 2021

The 6S RNA forms a specific, stable complex with the σ70 containing form of RNA polymerase, resulting in down‐regulation of transcription at many promoters. We have shown that the 6S RNA is near the active site of RNA polymerase, and surprisingly can be used as a template for RNA synthesis analogous to transcription from a DNA promoter template. Studies of 6S RNA complexes revealed that 6S RNA remains stably bound to RNA polymerase when nutrients are limiting, but when nutrients become available, 6S RNA is released from RNA polymerase as a result of its use as a template for pRNA synthesis.A phylogenetically conserved structure of 6S RNA is critical for function. This structure bears a striking resemblance to the DNA conformation in open complexes during transcription initiation, which suggested 6S RNA might contact RNA polymerase in a manner similar to DNA binding. Indeed, similar to DNA binding at most promoters, region 4.2 of σ70 is required for 6S RNA binding. However, analysis of the contribution of individual residues within region 4.2 of σ70 for 6S RNA binding revealed that RNA binding is distinct from promoter DNA binding. The nature of this 6S RNA‐RNA polymerase interaction as well as its impact on promoter specificity for 6S RNA regulation of transcription will be discussed.
Temporal and functional study of TGFβ regulated genes during chicken AV canal formation
Authors: Tavares Andre Luiz Pasqua , Runyan Raymond Bruce 
Published: June 2021

In the atrioventricular canal (AVC) of the embryonic heart, endothelia undergo an epithelial‐mesenchymal transition (EMT). This EMT is a multi‐step event, wherein TGFß2 mediates activation while TGFß3 mediates cell invasion. BMP2 has an unclear role in this EMT. We examined in vivo and in vitro patterns of expression of EMT‐related genes. In the chick, EMT is seen at stage 17 although signaling processes begin at stage 14. Our objective is to identify critical transcription factor function during EMT. We examined mRNA for Sox8, Sox11, Sip1, Brachyury, Hey2 and Runx2 by qPCR. Starting at stage 14, Sox8 and Hey2 showed upregulation while Brachyury was downregulated. Sip1 and Runx2 were down‐regulated only after EMT was visible. Sox11 mRNA levels did not show significant change (stages 14‐20). We explored changes in expression after TGFβ2, TGFβ3 or BMP inhibition of AVC explants on collagen gels. Anti‐TGFβ2 treatment produced significant upregulation of Sox8 and down‐regulation of Sox11, Sip1 and Runx2 while anti‐TGFβ3 treatment caused significant down‐regulation of Sox8, Sip1 and Runx2. Noggin treatment caused significant upregulation of Sox8, Sox11, Sip1 and Hey2 and down‐regulation of Brachyury. Localization of these molecules showed they were present in AVC endothelium and mesenchyme at the analyzed stages. These data suggest that each of these transcription factors may play a role in cardiac EMT. NHLBI.Grant Funding SourceNHLBI
The effects of replicative senescence and telomerase on contraction and motility of fibroblast cells
Authors: Peterson Joanne Lykins , Vaughan Melville 
Published: June 2021

Fibroblast cells are important in wound healing as they differentiate into myofibroblasts that can migrate into a wound and create tension and aging skin seems to take longer to repair a wound. This study was designed to look at the migration and contraction ability of early (EP) and late (LP) passage cells as compared to cells with telomerase (hTERT), an enzyme that lengthens telomeres delaying senescence. To assess contraction, all cells were grown on coverslips with and without transforming growth factor beta, a wound healing agent, and stained for alpha smooth muscle actin (α‐sma) a myofibroblast marker. Collagen lattice assays were used to assess contraction by measuring lattice diameter as it contracted over time then stained for the presence of α‐sma. Finally, a scratch assay was used to measure the ability for each type of cell to migrate into a "wounded" area. Contraction by EP cells was greater than LP cells in a five day collagen lattice. Results on migration assays and α‐sma in coverslips and collagen lattice are still being analyzed; however expected results would show that EP and hTERT cells should migrate faster and have more α‐sma than LP cells. If these results are shown, they would suggest that the formation of α‐sma in EP and hTERT cells allows faster migration and better contraction than in LP cells. Funding provided by the University of Central Oklahoma.Grant Funding SourceUCOIRB
Classroom Clickers Provide Reliable Formative Feedback: Three years experience in gross and microscopic anatomy curriculum
Authors: Alexander Cara Jae , Crescini Weronika , Lachman Nirusha , Pawlina Wojciech 
Published: June 2021

The goal of our study was to evaluate the effectiveness of the audience response system (ARS) as a tool for providing formative feedback to first year medical students. Over a three year period, we collected data from anatomy and histology courses in which students answered clinically oriented multiple choice questions using the ARS. We compared each student's cumulative ARS and final exam scores and we calculated a correlation coefficient between these two values. In addition, we conducted a questionnaire to evaluate the students' perception on ARS. According to our results, students saw ARS as useful for providing feedback on performance with a mean of 3.61 (1‐5 scale). There was a strong positive correlation between ARS and final exam scores. R values for the ARS and NBME Anatomy subject exam was R=.9556; and for the Anatomy/Radiology written exams, R=.9882. Students believed that ARS improved their performance with a mean of 3.94 (1‐5 scale). Students also preferred more frequent ARS quizzes with fewer questions to less frequent sessions with more questions (mean=3.74). In conclusion, students use ARS as a feedback tool and can rely on it as a good predictor of final course performance. We have found that ARS feedback motivates students to seek help from faculty when appropriate. It is user friendly, interacts well with PowerPoint, and is not time consuming for faculty.Grant Funding SourceAAA
Interactive group learning in a virtual microscopy world
Authors: Goldman Haviva M , Smith Janet D , Churchill Judy R , Smolen Arnold J , DePace Dennis M 
Published: June 2021

Virtual microscope technology presents new opportunities and challenges for curricular development in medical education. In our Problem Based Learning (PBL) curriculum at Drexel University College of Medicine, we chose to replace traditional microanatomy laboratory sessions with web‐based annotated virtual slide based assignments, self‐study guides, and self‐assessments for students to complete at home. We then used the laboratory time for group‐based review sessions that were comprised of structure scavenger hunts with student presentations and faculty facilitation. Following the first year of this format change, no significant difference in student practical exam performance was evident. However, performance on microanatomy multiple‐choice questions increased by 13%, suggesting enhanced understanding of microanatomy concepts. Since other curricular changes were also implemented this year, it is not possible to determine the degree to which the lab format change contributed to this increase. Student evaluations suggest the new format was preferred, and was an effective use of time. Laboratory participation averaged 99%, and 89% of students reported completing most at‐home assignments in advance of in‐lab sessions. We conclude that the new lab format encourages both independent and interactive‐group learning, and is well suited to the learning style of our PBL students.Grant Funding SourceDrexel University Professional Enrichment and Growth Grant
An analysis of the effectiveness of team roles during anatomy dissections
Authors: Elzie Carrie A. , Herring Nicole , Petrusa Emil , Pettepher Cathy , Dalley Arthur F. 
Published: June 2021

Vanderbilt University recently adopted an integrated medical curriculum which, like many schools, resulted in a reduction in the number of teaching hours designated for gross anatomy. The reduction in hours primarily affected the lecture portion of the class, while preserving as much time as possible for laboratory dissection. The active components of laboratory dissection are deemed essential to the learning process of the students at Vanderbilt University. Thus, to maximum the time spent in the laboratory students at each dissecting table have access to a large touch‐screen PC that provides the students with daily laboratory goals, dissection instructions and several electronic textbooks and videos that provide resources to aid in their dissection. Typically each table is shared by five students ‐ one of which is assigned to operate the computer, two serve as primary dissectors and two as assistant dissectors. The roles rotate every lab session to ensure that all students are exposed to each responsibility. Thus, this study seeks to investigate if there is a correlation between the student's assigned role and their performance on that particular portion of the practical exam. For instance, on the day of the heart dissection, will the primary dissector perform better on the practical questions specific to that lab than the assisting dissector or the computer operator? Data collected from this study will allow us to evaluate the effectiveness of our team roles during gross anatomy as well as assess the impact of the computers during dissection.Grant Funding SourceIRACDA NIH 5K12 GM068543‐04
A NEW COMPLEMENTARY ACTIVITY TO HISTOLOGY TEACHING
Authors: Monte‐Alto‐Costa Andréa , Romana‐Souza Bruna 
Published: June 2021

ObjectiveTo test a new complementary activity to histology teaching aiming to improving histology knowledge of undergraduated nursing students.MethodsStudents were divided into groups (6 per group). Each group received a file containing introduction, objectives, methodology and figures (such as graphics, tables and photomicrographs) of a scientific article focused in histological parameters (pathology of an organ). Students should analyze the material received and complete the article inserting title and conclusion, describing results and proposing clinical application. Furthermore, groups prepared an oral presentation and wrote an abstract about complete article.ResultsAll groups showed a good presentation and abstract describing results (mainly photomicrographs and graphics), connecting these results with its clinical relevance and presenting a creative title and a final conclusion. At the end, the students evaluated this activity and described three main positive points about it: it permitted to improve their histology knowledge, to associate theoretical concepts of histology with practical ones and to deepen theoretical concepts of histology.ConclusionsThis complementary activity to histology teaching improved histology knowledge of undergraduate nursing students, because these students deepened their theoretical concepts of histology, associated theoretical and practical concepts of histology and recognized the importance of histology in their professional life.This work was supported by Department of Histology and Embryology, State University of Rio de Janeiro (DHE‐UREJ).