bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dietary Potassium a Neglected Factor in Hypertension: Morphofunctional Evidence for Regulation of Cyclooxygenase‐2 and Kallikrein by Potassium
Authors: Vio Carlos , Salas Daniela , Hernandez Alejandra , Pedraza Paulina , Cespedes Carlos 
Published: June 2021

The importance placed on dietary potassium on health and disease is underscored compared with dietary sodium, and less effort has been placed on studies on adequate dietary potassium. The benefits of potassium rich‐food are known, however, the mechanisms of action are lacking. With the hypotheses that dietary potassium regulates renal sodium excretory hormones, we studied the effect of enriched potassium diet on kallikrein (Kall) and cyclooxygenase‐2 (COX‐2)SD male rats on normal potassium diet (0.9%, NK) or higher potassium diet (3%, HK) for 4 weeks, Kidney tissue was used for protein (Western blot), mRNA (RT‐qPCR), and cell features using immunohistochemistry (IHC). Kall was restricted to connecting tubule cells CNTc, HK increased the CNTc size and immunostaining with an hypertrophied pattern, increased Golgi and secretory‐like vesicles. Kallikrein increased its enzyme activity (42±3 vs 27±3 mU, p<0.005), protein by Western blot (1.3 fold p<0.05), and mRNA by qRT‐PCR (1.4 fold p<0.05). Kall activity correlated with UV potassium excretion (r=0.66, p<0.001). COX‐2 containing cells were restricted thick ascending limb cells TAL, in response to HK was observed a decreased COX‐2 cells number, a decreased protein level (0.4 fold p<0.05) and mRNA (0.5 fold p<0.05).There is a different cellular response of CNTc and TAL to higher potassium diet, Kallikrein CNTc respond with hypertrophy and increased synthesis, COX‐2 TAL cells respond by decreasing the number of cells, a recruitment phenomenon. Upregulation of Kall is consistent with its vasodilatory, natriuretic effect. Downregulation of COX‐2 requires further studies to elucidate its response to potassium.
Role of NaDC1 in Control of Urinary Excretion of α‐Ketoglutarate
Authors: Hering‐Smith Kathleen , Coleman‐Barnett Joycelynn , Huang Weitao , Hamm Lee 
Published: June 2021

Recent studies have suggested that urinary α‐Ketoglutarate (α‐KG) increases with alkali loads and decreases with acid loads. Also luminal α‐KG stimulates distal bicarbonate secretion via the Oxgr1 (GPR99) receptor.To investigate the role of sodium dependent dicarboxylate transporter, NaDC1, in regulation of α‐KG excretion, we studied NaDC1 knockout (KO) and Heterozygous (Het) mice on normal diet and with 72 hrs acid loading. Plasma and urine samples were analyzed by LC/Mass Spec.Also 14C‐α‐KG uptake was studied using HRPE cells overexpressing hNaDC1 (CUBS) and the proximal tubule (PT) OK cell line. OK cells express a novel calcium (Ca)‐sensitive dicarboxylate transport system.In mice, fractional excretion (FE) of α‐KG was dramatically increased in the KO and Het mice (WT 0.38+/‐0.05, Het 2.8+/‐1.3, KO 4.7+/‐0.9; p<0.05). Acidosis lowered FE significantly in all mice.In CUBS α‐KG uptake decreased when competed with the dicarboxylate succinate (Suc 2 mM) in both normal and <60 µM Ca buffers (0.64±0.11 to 0.25±0.10 and 0.63±0.15 to 0.29±0.11, p<0.01).In OK cells, α‐KG uptake increased when extracellular Ca was lowered to <60 µM (1.7±0.49 vs 2.5±0.6, p<0.01). Transport decreased when competed with Suc in both Ca buffers (1.3±0.39 vs 1.6±0.34, p<0.01).NaDC1 transports α‐KG and is the predominant, but not exclusive, mechanism of control of distal α‐KG delivery. Also α‐KG is transported via a Ca‐sensitive transporter in OK cells. Furthermore based on the FEs > 1.0, α‐KG is secreted into the PT simultaneously with reabsorption.Thus NaDC1 in the PT regulates acid‐base transport in the distal tubule via the control of α‐KG transport. NaDC1 represents a novel mechanism of PT–distal tubule communication in the kidney.NIH/NIDDK
Pro Inflammatory Cytokines in Smokers and Non‐Smokers Following Different Intensity of Exercises
Authors: Martinez Diego , Medina Erika , Valdez Ruben , Solis Leslie , Park Kyung‐Shin 
Published: June 2021

PurposeThe purpose of the study was to examine changes in C‐reactive protein (CRP) and TNF‐a in blood before and after exercise at different intensities in smokers compared to non‐smokers.MethodsFourteen physically inactive smokers (SM, n=7) and non‐smokers (NS, n=7) aged 18 to 26 were recruited. Each subject completed three treadmill runs at different intensities in a random order (60%, 70%, and 80% of VO2max). Running distance for all three runs was equivalent to 30‐min run at 70% VO2max. Plasma samples were collected at rest (PRE), immediately after (POST), and 1 h following (1H) each run to measure CRP and TNF‐a. Data was analyzed using two‐way repeated measures ANOVA with P<0.05.ResultsSM had greater values of CRP than NS at POST following 70% (3.3±.3mg/L vs. 2.5±.1, Mean±SE, P=.014) and 80% (3.9±.3 vs. 3.0±.3, P=.005) VO2max runs. CRP at POST increased relative to intensity in SM (60% < 70% < 80%, P<0.05), but not in NS (only 60% < 80%, P<0.027). TNF‐α was higher in SM at all measurements points (P=.015). TNF‐α at POST elevated above PRE at 60% (40.4±2.1mg/L vs. 52.4±4.2, P=.028), 70% (41.7±3.3 vs. 56.3±5.6, P=.019), and 80% (39.8±3.3 vs. 57.8±6.1, P=.023) VO2max runs in SM and 70% (27.9±3.1 vs. 34.3± 4.4, P=.041) and 80% (28.8±3.8 vs. 35.3±2.9, P=.033) VO2max runs in NS.ConclusionResults indicate SM having higher levels of inflammation even at rest as compared to NS, suggesting higher risk of cardio vascular disease. To exercise intensity CRP and TNF‐a elevate both groups. However, SM responded more sensitively to relatively equal intensity of exercise. These greater elevation in CRP and TNF‐α at POST suggest that high intensity aerobic exercise may be avoided in SM at least in the beginning phase of exercise training.
Resistance Training with Instability Increase Levels of Spinal Inhibition and Decrease the Motor Symptoms of Parkinsonians
Authors: Silva‐Batista Carla , Kanegusuku Hélcio , Roschel Hamilton , Mattos Eugenia , Tricoli Valmor , Forjaz Cláudia , Ugrinowitsch Carlos 
Published: June 2021

ObjectiveTo investigate the effects of resistance training with instability in the level of reciprocal inhibition and in the motor symptoms of individuals with Parkinson's disease (PD).Methods26 individuals with PD (8.9±0.5 disease duration) on dopaminergic therapy stable in stages 2 and 3 were divided equally into two groups: control group (CG) and RTI group (RTIG). RTIG underwent 12 weeks (twice a week) of hypertrophy‐oriented RT in the squat, leg press and plantar flexion exercises with the addition of instability devices (i.e., bosu, dyna disk, balance disk, Swiss ball). Soleus muscle reciprocal inhibition (RI) of the most affected leg and motor symptons using the Unified Parkinson's Disease Rating Scale (UPDRS) section III were measured before and after the training period. Significance level was set at p蠄0.05. Results: RI was significantly increased after RTIG (from 5.1±7.6% to 34.8±10.4% p<0.0001). Motor symptons were significantly decreased after RTIG (from 42.2±7.6 to 38.1±5.6, p<0.001).ConclusionRTIG is effective to improve the motor control of individuals with PD. Thus, RTIG may be a important training strategy for this population, once changes in the motor control are apparently indicative of an abnormal supraspinal influence on spinal mechanisms due to disease. Financial support: FAPESP: 2013/04970‐4.
ROS production from endothelial cells during in vitro simulated dives: effects of hydrostatic and gas pressures
Authors: Theron michael , Wang Qiong , Lambrechts Kate , Mazur Alexandra , Buzzacott Peter , Guerrero François 
Published: June 2021

ROS are known to be involved in post‐dive endothelial dysfunction which is itself thought to be associated with decompression sickness. The aims of this study were to assess the impact of air diving on ROS production from endothelial cells (EC) during diving, and to differentiate the effects of physical parameters of the dive (hydrostatic ‐HP‐ and gas pressures). This work particularly focused on the mitochondria, one the pathways of ROS production.During in vitro diving simulation (45 min at 8 ATA, compression 1ATA/min), superoxide (O2°‐) production, mitochondrial membrane potential (MMP) and cell death were analyzed on EC when HP, oxygen and nitrogen pressures were increased together (air dive) or independently. Then, O2°‐, peroxynitrite, NO° productions and mitochondrial calcium concentration were examined during air dive.Air diving increased O2°‐, decreased MMP and promoted endothelial cell death. O2°‐ production was mainly due to oxygen partial pressure but also to HP. HP, oxygen and nitrogen pressures modified mitochondrial membrane potential and cell death. During air diving, endothelial cells showed excessive O2°‐ and peroxynitrite production, attenuation of NO production and up‐regulation of mitochondrial calcium storage.This study clearly demonstrates the overproduction of ROS and RNS (O2°‐ and peroxinitrite) during a dive; it furthermore shows that MMP and mitochondrial calcium are modified. It is proposed that, during diving, mitochondrial calcium may promote peroxynitrite formation and O2°‐ overproduction through the activation of mitochondrial NO° generation. These phenomena could explain the observed decreased viability of endothelial cells.
Fine particulate matter in the air within the limits recommended by WHO alters placental structure
Authors: Soto Sonia , Marchesi Guilherme , Lopes Karen , Veras Mariana , Heimann Joel 
Published: June 2021

ObjectiveTo evaluate the effects of PM during the perinatal period on placenta.MethodsFemale Wistar rats (7‐9/group) were exposed to filtrated air (F) or PM2.5 (P) for 15 days. After mating, rats were divided in 4 groups and again exposed to F or P (FF, FP, PF, PP). At the 19th day of pregnancy, fetal (fPl) and maternal (mPl) portions of placenta were collected. Several placental parameters and renin‐angiotensin system were evaluated.Results(mean±SEM – p<0.05):

FF
FP
PF
PP

Mass (g)
fPl
0.42±0.01
0.44±0.01
0.40±0.011,2,4
0.43±&lt;0.01

mPl
0.13±0.01
0.14±0.01
0.12±0.011,2
0.12±0.011,2

Thickness (mm)
fPl
4.42±0.10
4.16±0.06
3.93±0.091,4
4.40±0.11

mPl
3.15±0.10
2.77±0.091
2.92±0.09
2.95±0.11

Surface area (mm2)
fPl
117.6±2.37
90.20±2.191
101.1±2.971,2
101.7±2.281,2

mPl
32.64±1.46
24.0±0.601
28.4±1.111,2
26.73±1.461

TGFβ (%)
fPl
100
76.93±8.581
76.63±3.761
83.30±5.96

mPl
100
72.70±6.351
48.58±5.901,2
49.54±5.771,2

AGTO (%)
fPl
100
121.7±15.69
127.9±10.29
115.3±11.36

mPl
100
104.9±10.75
114.6±19.30
85.87±4.28

ECA (%)
fPl
100
90.17±5.27
74.20±4.841,2
59.78±3.361,2

mPl
100
96.96±4.39
82.04±3.161,2
80.41±4.961,2

Renin (%)
fPl
100
192.8±27.791
204.3±21.371
149.9±20.021

mPl
100
139±11.06
113.5±18.57
120.7±26.42

ANG II (%)
fPl
100
90.52±3.711
90.82±2.311
83.28±2.131

mPl
100
104.5±11.72
105.2±8.82
75.97±3.291,2,3

AT1R (%)
fPl
100
202.1±41.161
118.7±17.69
142.3±15.91

mPl
100
99.71±11.19
75.58±5.21
36.63±4.021,2,3

AT2R (%)
fPl
100
97.06±8.51
63.69±11.221,2
39.46±7.541,2

mPl
100
91.10±7.97
73.86±10.37
39.77±7.101,2

P<0.05 1vs FF; 2vs FP; 3vs PF; 4vs PP.ConclusionsParticulate matter alters placental structure and local renin‐angiotensin system with a possible prejudice on maternal‐fetal interface.
Neuromodulator Permeability of a Ganglionic Sheath in the Lobster, Homarus americanus
Authors: Keller L , Christie A , Dickinson P 
Published: June 2021

Rhythmic movements, controlled by hard‐wired neuronal networks, must be flexible in order to respond to environmental changes. Neuromodulators, released either locally within the nervous system or hormonally, provide one source of flexibility. The pyloric motor pattern, which is generated in the lobster stomatogastric ganglion (STG) and controls rhythmic movements of the foregut, is extensively modulated by neuropeptides. However, the STG is encased in a connective tissue sheath that can limit access to the ganglion; medium‐sized, hydrophobic crustacean cardioactive peptide can permeate the sheath but large, hydrophilic Val1‐SIFamide cannot. We hypothesize that size and hydrophobicity, which can be combined as total polar surface area (TPSA), are two factors that dictate this selective permeability. The pyloric pattern was recorded extracellularly in the isolated stomatogastric nervous system. Neuropeptides spanning a range of TPSA values were superfused over the STG; the threshold concentration for activation and the intensity of activation for each peptide were compared with the sheath intact and after its removal. The modulatory threshold for both red pigment concentrating hormone, a large, hydrophobic peptide with a medium TPSA, and proctolin, a small, hydrophilic peptide with a small TPSA, was between 10‐9 and 10‐8M both with and without the sheath present. However, the intensity of activation for proctolin was greater without the sheath than with, indicating the sheath may partially block proctolin. These results suggest that TPSA is a possible determinant of the permeability of the connective tissue sheath encasing the STG.Support: APS UGSRF, NIH 5P20‐RR‐016463, 8P20‐GM‐103423 (INBRE)
Student Evaluation of Case Studies.
Authors: Jagadeesh Ashraya , Volodymyr Mavrych , Bolgova Olena , Maroun Leonard , Rajasekaran Senthil Kumar 
Published: June 2021

There is strong research evidence that supports the implementation of learner centered approach as opposed to instructor centered approach in expanding knowledge base as well as increasing motivation.This study attempts to assess student evaluation and acceptance of learner centered teaching within the basic science program of a Caribbean medical school through the use of case studies in Microbiology and Anatomy to help determine its usefulness in the basic science curriculum. In addition, we gathered data to assess differences in perception relative to the student's progression in the curriculum.In both the Microbiology ((M)(3rd Trimester) and Anatomy (A)course (1st Trimester), case studies were prepared at the end of the relevant lecture series and handed out to students during class time. Further, students were encouraged to work in small groups to facilitate collaborative thinking in solving the case. At the end of the exercise, students answer questions in the form of multiple choice questions (MCQ ) pertaining to the cases.Upon completion of the case studies, students were surveyed using a questionnaire.We found that students in Anatomy were less comfortable with the use of case studies when compared to the Micro students (46%vs 66%)
imageThis difference appeared to be related to the stage of progression of the student in the curriculum with senior students being more receptive to the case studies. 55% of the Micro students felt it was a good use of their time while only 21% of anatomy students did so.There was a consistent opinion among students regardless of their stage in the curriculum that they did not want this activity to be graded (96% (A) and 81%(M)).ConclusionIt appears that more advanced students provided a more positive evaluation.
Medical Gross Anatomy: Interdisciplinary Efforts to Increase Active Learning through Collection and Histological Assessment of Biopsies
Authors: Davies David , Quick Charles 
Published: June 2021

ObjectiveIn a 9‐week anatomy course, collaboration between Anatomy and Pathology faculty members facilitated the pairing of an investigative approach with traditional dissection to: encourage self‐directed active learning, link gross anatomical observations with normal and pathologic histological findings, and build teamwork and communication skills.Methods and ResultsWhile engaged in dissection, each of 35 teams independently obtained seven biopsies prioritized by their scientific interest and processing cost. A clinical pathology laboratory processed the tissues to histopathological slides that teams initially reviewed with a pathologist. Subsequently, teams examined their slides using microscopes equipped with mounts to support cell phone cameras. This enabled students to document and share their findings using techniques applicable to telemedicine. The investigative proficiency of the teams was assessed by capstone reports and 12‐min presentations that were evaluated by three faculty members during an intramural biomedical conference.ConclusionsFaculty scoring and narrative assessments indicated that this endeavor: 1) firmly grounded student learning of anatomy and histology in a clinical context, 2) fostered self‐directed learning, 3) encouraged students to explore their personal interests as prospective lifelong learners, and 4) documented their ability to present accurate, concise, and well‐organized reports. Moreover, interviews with students suggested that this investigative approach to learning was popular and effective.Support: 1) Arkansas Medical Society's Medical Education Foundation for Arkansas, 2) Dept. of Pathology, and 3) Dept. of Neurobiology and Dev. Sciences.
Anatomy and Additive Manufacturing: Imaging Methods and 3D Printing in Anatomy Education and Research
Authors: Adams Justin , Bertram John , McMenamin Paul 
Published: June 2021

The combined challenges of maintaining bequest programs, accessing and retaining human cadavers, and minimising staff and student exposure to formalin has led to variable (and oftentimes reduced) use of dissection‐based teaching in medical and allied health professional programs. As a supplement to our current dissection‐based curriculum, we have developed methods for applying imaging and additive manufacturing to reproduce prosected human cadaver and other specimens that obviates many of the above issues.This report presents the results of several years of methods research and development to produce high resolution, full color reproductions of prosections from medical imaging (CT/MRI) and surface scanning datasets. We describe how this approach of preserving anatomy offers several advantages over other techniques, including: (1) capturing anatomy too complex for traditional physical moulding and casting methods; (2) the rapid production of multiple identical copies; (3) scale manipulation; and (4) false coloring to enhance structure visibility. We also present statistical results (concordance and intraclass correlation coefficients) which demonstrate that 3D prints from surface scanned specimens have high concordance to the original, and accurately resolve the morphology of extremely small structures without reliance on CT/MRI for primary data collection.Our ongoing development of 3D printing for anatomy education represents a significant methodological advance impacting the range of resources available to training programs, particularly in avoiding some of the financial, cultural and ethical issues associated with cadaver specimens either in an embalmed or plastinated form.
A Study of Unmyelinated Afferent Axons in the Suburothelium in Women with Urinary Stress Incontinence.
Authors: Abtahi Bahareh , Venner Kerrie , Groves Mike , Elneil Sohier 
Published: June 2021

Study objectiveTo study the nerve profile of unmyelinated axons beside the suburothelial myofibroblasts, as neuroeffectors, in comparison to the axons in other sites of the suburothelium.MethodsThis is a prospective study. Bladder biopsies were obtained using rigid cystoscopy from four patients with urinary stress incontinence. Suburothelial nerve bundles were studied at two sites: those adjacent to myofibroblasts (Nmyo) and those located within other sites of the suburothelium (Ns). Axonal contents of unmyelinated nerve bundles and Schwann cells within the suburothelium were studied using transmission electron microscopy.ResultsThe mean age of patients was 56 ±15 years. All patients had normal bladder function (maximum cytometric capacity: 554±57 mL). The total of 93 axons beside myofibroblasts and 118 axons in other sites of suburothelium were counted. The mean number of axons per nerve bundle was similar in both groups of nerve bundles (Nmyo: 3.03 vs Ns: 2.95). However, the mean number of large dense cored vesicles (LDCV) and small vesicles (SV) was higher in Nmyo group in comparison to the Ns group
imageand
imageThe values were (Nmyo:16 vs Ns:12.61) for LDCV and (Nmyo: 1.05 vs Ns: 0.79) for SV. The percentage of activated Schwann cells was higher in Nmyo in comparison to the Ns group (52% vs 32.5%).ConclusionThis study showed that the axonal contents of the nerve bundles adjacent to myofibroblasts had a higher amount of neurotransmitters within them, as compared to nerve bundles elsewhere. This supports the hypothesis that suburothelial myofibroblasts play a role in neuronal signalling.
A Cerebral Clearance Pathway for Amyloid β
Authors: Morris Alan , Hawkes Cheryl , Weller Roy , Carare Roxana 
Published: June 2021

ObjectiveThe objective of this study was to define the clearance pathway of Amyloid β (Aβ) from the brain at the ultrastructural level.BackgroundCerebral Amyloid Angiopathy (CAA), the deposition of insoluble Aβ in the walls of cerebral blood vessels, is present in the elderly and Alzheimer's disease (AD) brain. Failure of the clearance of Aβ from the brain along 100‐150nm‐wide basement membranes (BMs) in the walls of capillaries and arteries is thought to contribute to the accumulation of Aβ as CAA. However, the exact localization of Aβ within the BM as it drains from the brain has not yet been determined.Methods10 week old male C57/BL6 mice were injected into the hippocampus with 0.5 uL of 10μM biotinylated soluble human Aβ40 before being transcardially perfused with 0.01M PBS, followed by 4% paraformaldehyde. Brains were sectioned and processed by immunocytochemistry for detection of biotin using DAB as chromagen. Sections were then processed for transmission electron microscopy and imaged using a Hitachi H7000 TEM.ResultsExogenously injected Aβ40 was detected in the BM of hippocampal capillaries 5 minutes after injection.ConclusionsThese results suggest that Aβ40 enters the cerebrovascular BM as it is cleared from the brain and could prove significant in further understanding the pathogenesis of CAA and AD.
Antioxidant Enzymes Activities and Lipid Peroxidation of Aqueous Extracts of selected Vegetables in Isoproterenol‐induced Myocardial Infarction in Male Wistar Albino Rats
Authors: Okpuzor Joy , Salisu Titilayo 
Published: June 2021

Vegetables constitute a substantial portion of most daily diet and also a part of an overall healthy diet worldwide. This present study examined five leafy vegetables generally eaten in some parts of South Western, Nigerian and include L. taraxacifolia (Wild lettuce), C. crepidioides (Fireweed), S. nigrum (Black nightshade), B. alba (Indian spinach) and S. biafrae (English spinach). The vegetables were air dried in the laboratory for two weeks and extracted with water using maceration techniques. The effect of the extract on isoproterenol‐induced (ISO) myocardial infarction model was evaluated in male Wistar rats (150‐200 g).The rats were randomized into eight groups of six rats each. Groups A and B served as normal and ISO controls and were fed with rat pellet and water ad libitium. Groups C, D, E, F, G and H were the experimental groups pre‐treated orally with 200 mg kg‐1bw‐1 of each extract respectively for 28 days. Group H however, received a combination of all the extracts in ratio 1:1:1:1:1. On day 29 and 30, groups B to H excluding group A received ISO subcutaneously at a dose of 20 mg kg‐1 bw‐1 to induce myocardial infarction based on the preliminary results from our laboratory.The activities of superoxide dismutase, catalase and reduced glutathione were significantly elevated (P<0.05) in all the pre‐treated groups compared to the ISO control while the malondialdehyde levels decreased significantly (P<0.05) in all the groups including normal control compared to ISO group.We therefore, suggest that these vegetables extract may be effective in the management and prevention of myocardial infarction and so could be formulated into food supplements