bluuebunny/crossref_metadata_2025_split huggingface dataset:
The involvement of norepinephrine, neuropeptide Y and nitric oxide in the cutaneous vasodilator response to slow local heating
Authors: Hodges Gary J , Kosiba Wojciech A , Zhao Kun , Johnson John M 
Published: June 2021

Adrenergic blockade abolishes the axon reflex (AR) during slow local heating and reduces the final vasodilator response. We tested whether the neurotransmitters, norepinephrine (NE) and/or neuropeptide Y (NPY) were involved and whether they acted via nitric oxide synthase (NOS). In 7 subjects, 4 forearm sites were instrumented with microdialysis fibers, local heaters and laser‐Doppler probes. Part 1: treatments were untreated control, propranolol (PRO) and yohimbine (YOH) to antagonize a‐ and ß‐adrenergic receptors, BIBP to antagonize Y1‐receptors and combined PRO, YOH and BIBP. Sites were locally heated from 33 to 40°C over 70 min. PRO+YOH or BIBP raised the temperature at which AR occurred or abolished it. The combination treatment consistently eliminated it. Overall vasodilation at the PRO+YOH and BIBP sites was less than at the control site. To test whether NE and NPY were acting via NOS, treatments were: untreated control, bretylium (BT) to stop neurotransmitter release, L‐NAME to inhibit NOS and BT+L‐NAME. The AR was absent at all treated sites. The decrease of the final vasodilation was not different among sites. These data suggest that NE and NPY are important for the AR and achieving complete vasodilation. Additionally, vasoconstrictor nerve and NOS blockade does not have an increased inhibition, suggesting that NE and NPY promote vasodilation via an NO‐dependent mechanism.Supported by NIH, HL‐059166
High‐salt intake up‐regulation of AT1 and AT2 protein expression in the left ventricle is independent of blood pressure
Authors: Ferreira Daniele Nunes , Coelho Michella Soares , Oliveira Ivone Braga , Rosa Kaleizu T. , Heimann Joel C. 
Published: June 2021

Objective:To evaluate the mechanisms of cardiac hypertrophy (CH) induced by salt overload.Methods:Eighteen‐week‐old Wistar rats received a normal (NS: 1.3% NaCl), a high 1 (HS1 4%), a high 2 (HS2 8%) salt diet, or HS2+hydralazine (HZ). Tail cuff blood pressure (BP), myocyte transverse diameter (TD) and interstitial fibrosis (IF) were evaluated in the left (LV) and right ventricle (RV). The angiotensin II type 1 (AT1) and 2 (AT2) receptors, collagen I (COL 1) were measured in the LV by Western blot.Results (mean±SEM – p<0.05, n=4–8/group):BP (mmHg) was higher on HS1 (150±2) and HS2 (154±3) than on NS (123±2). BP on HS2+HZ (126±2) did not differ from NS. LV TD was higher on HS1 (15±0.2), HS2 (16±0.7) and HS2+HZ (15±0.2) compared to NS (13±0.6). Similar results were observed by echocardiographic LV mass determination. RV TD was higher on HS2 (16±0.7), HS2+HZ (17±0.4) than on NS (12±0.4). IF (%) and COL 1 (AU) were higher on HS1, HS2 than on HS2+HZ and NS (COL I: 11319±625, 9603±185, 3666±920, and 5653±134, respectively). IF did not differ among the four groups in the RV. AT1 and AT2 were higher on HS2, HS2+HZ than on NS (AT1: 19276±722, 20421±602, and 17392±338, respectively).Conclusions:High salt diet leads to CH independently from BP. IF in HS2 is due to a direct effect of salt overload and an indirect effect through a higher BP. It can be speculated that increased AT1 and AT2 may be associated with the mechanism of salt induced CH.FAPESP
CNS blockade of aldosterone synthase prevents sympathetic hyperactivity and hypertension by central Na+ loading in Wistar rats
Authors: Huang Bing S. , Ahmad Monir , White Roselyn A. , Jeng Arco Y. , Leenen Frans H. H. 
Published: June 2021

In Wistar rats increasing CSF [Na+] by intra‐cerebroventicular (icv) infusion of hypertonic saline induces sympathetic hyperactivity and hypertension, which are prevented by blockade of brain mineralocorticoid receptors (MR). We postulated that locally in CNS produced aldosterone (aldo) is involved. Wistar rats instrumented with icv cannula were chronically infused icv with artificial CSF (aCSF), Na+‐rich (0.8 M) aCSF, aCSF plus aldo synthase inhibitor FAD286 (100 μg/kg/d), or Na+‐rich aCSF plus FAD286, using osmotic minipumps. After 2 wks of infusion, resting BP, HR & renal sympathetic nerve activity (RSNA) in response to air‐stress, & baroreflex function as well as hypothalamic and plasma aldo and corticosterone (corti) were examined.In another set of Wistar rats, via telemetry 24 h BP and HR were recorded 3 days before and 14 days after icv infusion of Na+‐rich aCSF with or without FAD286. Icv infusion caused sustained increases (~10 mmHg) in 24 h average MAP, which were absent in rats with FAD286 treatment. These data suggest that in Wistar rats a small increase in CSF [Na+] may increase biosynthesis of corticosterone and aldosterone in the hypothalamus, and mainly aldosterone activates CNS MR, leading to sympathetic hyperactivity and hypertension.Supported by a grant from Canadian Institutes of Health Research.
The Wilms Tumor Suppressor Protein (WT1) splice variants WT1(‐KTS) and WT1(+KTS) show distinct influences on different control levels of the Renin gene expression
Authors: Steege Andreas , Fähling Michael , Martinka Peter , Patzak Andreas , Brinkmeier Thomas , Persson Pontus B. , Scholz Holger , Mrowka Ralf 
Published: June 2021

Clinical studies indicate that Renin gene expression is controlled by the WT1 splice variants WT1(‐KTS) and WT1(+KTS). We investigated the underlying mechanisms through which they influence the Renin gene expression. Over expression of both WT1 variants in human kidney cells decrease the Renin protein level. Reporter gene studies demonstrate that the WT1 splice variants modulate the Renin promoter activity either directly (+KTS form) or through interactions within a regulatory region [hRENc] (both variants). WT1(+KTS) has an activating influence mediated by the Renin promoter. The WT1(+KTS) variant is able to interact with the Renin mRNA‐UTRs in contrast to the WT1(‐KTS) form. We show that the Renin mRNA undergoes a translocation into a translational inactive compartment after over expression of the WT1(+KTS) variant. The posttranscriptional influence of WT1(+KTS) may be responsible for a translational arrest of Renin synthesis, which explain the decrease of the Renin protein following WT1(+KTS) over expression. Both variants of the Wilms Tumor Suppressor Protein inhibit the Renin synthesis through distinct and different mechanisms and thus may participate in a hyperreninism in patients suffering from Wilms Tumor.Research support: Pontus B. Persson, Institut für Vegetative Physiologie, Charité‐Universitäts medizin Berlin, Tucholskystr. 2, 10117 Berlin, Germany
Short axis inferior vena cava measures are more sensitive than long‐axis measures in defining acute volume loading in normal human volunteers.
Authors: Chuen M. Jennyfer Ng Kam , Lip Gregory Y. H. , MacFadyen Robert J. 
Published: June 2021

IntroductionChange in inferior cava diameter (IVC) during respiration is a potentially non invasive measure of blood volume in haemodialysis (HD) and heart failure (HF) patients. We tested its sensitivity to acute volume loading in normal volunteers (NV).Methods30 NV (16 male; 48.7 ± 8.6 years, range 48–63) received intravenous 0.9% saline (IVS; 1.5 L over 20 minutes). IVC was measured by M‐mode echocardiography in long‐(LAX) and short‐axis (SAX) views during expiration (IVCe), inspiration (IVCi) and maximal inspiration (IVCmi) at 0, 1, 2 and 4 h. IVC was corrected for body surface area (IVCD) and IVC collapsibility index (IVCCI) was defined as IVCCIi=[(IVCe‐IVCi)/IVCe] × 100.ResultsThere was good linear correlation between LAX and SAX IVC [IVCe: r=0.809; p<0.0001, IVCi: r=0.660; p<0.0001 and IVCmi: r=0.498; p=0.005]. Parameters increased following IVS, with greater change from baseline in SAX. Only IVCe and IVCDe in SAX increased significantly following IVS (Table 1).ConclusionsDespite good correlation between LAX and SAX, SAX inferior vena cava indices are more responsive to IVS in NV. Further studies to assess the utility of these indices in the routine care of HF and HD patients are indicated.FundingHaemostasis Thrombosis and Vascular Biology Unit charitable funds.
The diagnosis of brachial plexus lesion: anatomical knowledge as an essential tool in poorly imaging facilities conditions
Authors: Gashegu Julien Kagabo 
Published: June 2021

The diagnosis of the lesion of brachial plexus is a challenge in country where imaging facilities are not well developed. Here we present 3 cases of different lesions of the brachial plexus after a road traffic accident.The first case presents a lesion of the 3 primary trunks of the right brachial plexus. The clinical examination showed paralysis of all terminal nerves of the brachial plexus and the collateral branches of both anterior and posterior brachial plexus.The second patient showed paralysis of all muscles of the shoulder and muscles of the anterior compartment of the arm. This clinical feature is in accordance of the upper brachial trunk lesion. The third patient showed a paralysis of muscles of the hand being innerved by median nerve or ulna nerve. He showed also paralysis of muscles of the anterior compartment of the forearm and anaesthesia of the medial region of hand and forearm. This clinical feature is in accordance with a lesion of inferior primary trunk. All diagnosis were made by analysis of the clinical features. The anatomical knowledge is very important in the clinical examination as one can confuse the signs of terminal nerves lesion with the trunk's lesion.
Influence of tumor stroma on normal keratinocyte marker profile
Authors: Lacina Lukas , Cada Zdenek , Dvorankova Barbora , Kolar Michal , Strand Hynek , Smetana Karel 
Published: June 2021

Study objective:This study reports on marker profiling changes of normal keratinocytes under influence of mesenchymal cells derived from tumor stroma in vitro, and especially on induction of stem‐cell‐like features in affected epithelia.Methods:We compared phenotype of human tumors with in vitro model where growth and phenotypic pattern of normal human keratinocytes were monitored under influence of various types of fibroblasts including those prepared from stroma of malignant tumors. We visualized panel of keratins, endogenous lectins and binding sites for endogenous lectins, proliferation marker Ki67, membrane protein Ber‐EP4, nucleolar protein nucleostemin and markers of poorly differentiated embryonic stem cells Oct‐4 and Nanog.Results:The results demonstrated that normal human keratinocytes were strongly influenced by tumor stromal cells. The observed epithelial cells subsequently expressed tumor markers as keratin 8 and epithelial antigen Ber‐EP4 as well as some putative stem cell markers (e.g. keratin 19, nucleostemin etc.)In conclusion, the cancer stromal cells significantly influenced the phenotype of normal keratinocytes, suggesting so the role of epithelial – mesenchymal interaction in cancer cells survival and spreading.
Conformational dynamics of mutant forms of formamidopyrimidine‐DNA glycosylase from Escherichia coli
Authors: Fedorova Olga , Kuznetsov Nikita , Koval Vladimir , Douglas Kenneth , Zharkov Dmitry 
Published: June 2021

Formamidopyrimidine‐DNA glycosylase (Fpg) repairs oxidative DNA damage by removing oxidized purines such as 8‐oxoguanine (8‐oxoG) from DNA. Fpg possesses three activities resulting in the excision of the damaged deoxynucleoside: hydrolysis of the N‐glycosidic bond, β‐elimination, and δ‐elimination. Phenylalanin‐110 is one of the residues inserted in the DNA helix after evertion of 8‐oxoG into the enzyme's active site. We have studied conformational dynamics and pre‐stationary kinetics of Fpg and its mutant forms F110W and F110A by the stopped‐flow approach with tryptophan (Trp) and 2‐aminopurine (2‐aPu) fluorescence detection. Multiple transient changes in Trp and 2‐aPu fluorescence were observed, indicating sequential conformational changes in both protein and DNA molecules during the catalytic cycle. An induced fit model is proposed that provides a mechanism for substrate recognition and cleavage. Distortion of the DNA helix coupled with the evertion of oxidized base and insertion of amino acids occured in the initial steps of specific site recognition. Fpg‐F110A was not able to proceed beyond base eversion, while Fpg‐F110W revealed that the enzyme likely partially everts normal G in the search for a lesion.Supported by grants from the Wellcome Trust, RFBR, and INTAS.
A novel tRNA degradation pathway that acts on mature tRNA
Authors: Chernyakov Irina , Whipple Joseph M. , Kotelawala Lakmal , Grayhack Elizabeth J , Phizicky Eric M 
Published: June 2021

Under normal conditions, tRNA biosynthesis results in extremely stable species that are exquisitely adapted for their specific roles in translation. Newly transcribed tRNAs undergo multiple processing steps and several quality control checks before use in the cytoplasm. We recently provided evidence for a mechanism to examine the integrity of mature tRNAs in the yeast Saccharomyces cerevisiae, since mature tRNAVal(AAC) in a trm8‐Δ trm4‐Δ strain (lacking 7‐methyl‐guanosine and 5‐methyl‐cytidine) is rapidly degraded and deacylated upon shift to 37°C, resulting in a growth defect (Alexandrov et al., 2006, Mol. Cell 21:87–96).We have examined the components required for this tRNA degradation pathway as well as the generality of this pathway for different tRNA species and modifications. We find that degradation of tRNAVal(AAC) is mediated by Met22, as well as the 5′–3′ exonucleases Rat1 and Xrn1, which also have established roles in rRNA and snoRNA processing, and mRNA turnover. Furthermore, we find that this MET22‐dependent pathway mediates the degradation of at least three other tRNA species defective in other tRNA modifications. This evidence firmly establishes the existence of a pathway that monitors the integrity of mature tRNAs.Funded by NIH grants 5T32GM068411 and GM52347.
Dissescting the role of SBP2 in selenocysteine incorporation
Authors: Donovan Jesse , Caban Kelvin , Copeland Paul R 
Published: June 2021

The SECIS binding protein, SBP2, is required for the co‐translational incorporation of selenocysteine (Sec) at specific UGA codons. The C‐terminal 447 residues of SBP2 (CTSBP2) are sufficient to promote Sec incorporation and have been divided into a functional domain (FxD) and an RNA binding domain (RBD). SECIS and ribosome interactions through the RBD are well characterized but it is not known how the FxD participates in Sec incorporation. To determine the role of the FxD in Sec incorporation we created chimeras using the domains of CTSBP2 and the analogous region of SBP2‐like protein (SLP) to determine if the FxD in SLP has sufficient identity with SBP2 to promote Sec incorporation. Using an in vitro luciferase reporter specific for Sec incorporation, we showed that the FxD in SLP cannot promote Sec incorporation. A homology driven approach was used to mutate FxD residues in groups of five and mutant proteins were assayed for their ability to promote Sec incorporation, SECIS binding, and ribosome binding. We identified three regions critical for Sec incorporation that implicate the FxD in ribosome binding and suggest that SBP2's ribosome interaction is dynamic. Additionally, we expressed the FxD and RBD as separate recombinant proteins and assayed them for their ability to promote Sec incorporation. Interestingly, we found that both domains together in a Sec incorporation assay are competent but gel filtration and EMSA studies failed to show a stable interaction of the two domains. We currently hypothesize that the FxD acts to allow Sec‐tRNASec access to the ribosomal A‐site and are developing assays to test this.This work was supported by PHS grants T32AI007403 (JD), FGM081920A (KC), and GM077073 (PRC).
Functional Analysis of the ClC‐2 hyperpolarization‐activated Cl− channel in Mouse Colon.
Authors: Catalan Marcelo A , Sepulveda Francisco V , Melvin James E 
Published: June 2021

ClC‐2 is a hyperpolarization‐activated Cl− channel expressed in epithelial cells lining the gastrointestinal tract. ClC‐2 expression has been proposed to compensate for the intestinal Cl− secretion deficit in cystic fibrosis due to mutations in the Cl− channel CFTR.The overall goal of this project was to evaluate the ability of the ClC‐2 Cl− channel to stimulate intestinal fluid secretion. Distal colon sheets from ClC‐2 +/+ and ClC‐2 −/− mice were mounted in Ussing chambers and Cl− secretion was induced by two different paradigms: a) cAMP‐ and b) Ca2+‐increasing secretagogues. Neither cAMP nor Ca2+ ‐ mediated Cl− secretion was affected in ClC‐2 −/− colon. In contrast, the amiloride‐inhibited short circuit current (ISC) increased in the early distal colon of ClC‐2 −/− mice.Based on our findings, the ClC‐2 channel appeared not to be necessary for Cl− secretion in colonic epithelium. On the other hand, increased amiloride‐sensitive ISC in the early distal colon of ClC‐2 −/− mice suggested that there was an increased expression of the epithelial Na+ channel ENaC, the key component of the electrogenic NaCl absorption process. We conclude that a compensatory NaCl absorptive mechanism was activated in the early distal colon of ClC‐2 −/− mice, implying that the ClC‐2 channel might be important for colonic NaCl absorption.This work was supported in part by grants from NIH (DE09626) and Takeda Pharmaceutical Company, Inc.
Deciphering the indolence of osteomyelitis: Evaluation of the uptake of Staphyloccocus aureus and silver nanoparticles into osteoblasts
Authors: Wagner William , Benjamin Joseph C. , Webb Lawrence X. , Coldren Faith , Kute Timothy , Martin Eileen , Smith Thomas L. , Smith Beth P. 
Published: June 2021

Chronic osteomyelitis caused by Staphylococcus aureus is difficult to treat because the bacteria persists inside osteoblasts. The first aim of this study was to assess the uptake potential of S. aureus into osteoblasts. Because novel therapies are needed to combat the increasing antibiotic resistance of S. aureus, the uptake of silver nanoparticles (a possible therapy) into osteoblasts also was examined. Osteoblasts were incubated with carboxyfluorescein‐succinimidyl ester (CFSE) labeled S. aureus or silver nanoparticles and stained for confocal microscopy. Incubated osteoblasts were evaluated using flow cytometry for their FITC fluorescence profile (S. aureus) or SSC (side scatter) changes (nanoparticles). Osteoblasts were incubated with nanoparticles at different concentrations to determine their cytotoxicity. Flow cytometry showed that the FITC fluoresence was higher in infected osteoblasts due to incorporation of CFSE‐labelled S. aureus while SSC was greater due to the incorporation of silver nanoparticles. Confocal microscopy images confirmed the uptake of both S. aureus and nanoparticles. Nanoparticles demonstrated minimal cytotoxicity at low concentrations (MTS assay).Aided by a grant form the Orthopaedic Research and Education Foundation and the Translational Science Institute at Wake Forest University Health Sciences
RENAL PATHOLOGY AND MORPHOMETRIC STUDIES ON NATURAL HISTORY OF BXSB LUPUS MICE
Authors: Ahmed Atif A , Jones Olcay Y 
Published: June 2021

IntroductionBXSB is a prototypic murine model for Systemic Lupus Erythematosus manifested. Although few scoring systems have been reported in the literature, there has been no consensus on how to evaluate murine lupus nephritis.MethodsPost mortem renal tissue sections from male BXSB mice at 10, 20 , 30, 40 and 50 weeks of age (collectively n=45 ) were evaluated for histopathology on H&E, and PAS staining. Quantitative measurements of glomerular cell count, glomerular tuft area, and glomerular sclerosis areas were obtained on an average of 10 glomeruli per mouse by using computerized image analysis provided by Nikon. Controls were age matched male C57Bl/6 (n=3 per group) or female BXSB (n=3 at 30 weeks) mice.ResultsThere is progressive increase in glomerular cellularity and tuft size with age in mice at 10 and 20 weeks of age, compared to controls. Sclerosis was evident starting at 30 weeks. Four major step of progression were appreciated: 1) increased glomerular cellularity with increased glomerular size at 10th and 20th week of age; 2) expansion of matrix at 20 to 30 weeks of age; 3) progressive sclerosis with corresponding decreased cell counts, in mice at 30 to 40 weeks of age; and 4) end‐stage disease with pan‐sclerosis and glomerular obliteration in older mice.ConclusionsThe renal pathology in BXSB follows a predictable pattern that resembles human renal pathology. Computerized quantitative measurement of glomerular cell counts, tuft size and extent of sclerosis is a reliable objective tool to study lupus nephritis in mouse models and effect of experimental treatment options.
Atorvastatin reduces sympathetic nerve activity through the inhibition of Rac1/NAD (P) H oxidase and upregulation of Mn‐SOD in SHRSP
Authors: Kishi Takuya , Hirooka Yoshitaka , Ito Koji , Araki Shuichiro , Konno Satomi , Sunagawa Kenji 
Published: June 2021

BackgroundStatin is consider to protect for neuroplasticity. We demonstrated that oral administration of atorvastatin decreases sympathetic nerve activity (SNA) through the anti‐oxidant effect in rortral ventrolateral medulla (RVLM) of stroke‐prone spontaneously hypertensive rats (SHRSP). We hypothesized that atorvastatin might protect for neuroplasticity by reduction of oxidative stress in RVLM of SHRSP.Methods and ResultsIn SHRSP, intracerebroventricular infusion of atorvastatin (20 μg/kg/day) (ATORVA) for 14 days significantly reduced systolic blood pressure, heart rate and SNA (‐28±3 %, n=5, P<0.01) in comparison with vehicle infusion (CNT). In the RVLM, ATORVA decreased oxidative stress, Rac1 and NAD (P) H oxidase activity. ATORVA also significantly lowered the expression of Rac1, gp91phox, p22phox in membrane fraction, and p47phox in cytosolic fraction. In contrast, the expression level of Rac1 in cytosolic fraction and Mn‐superoxide dismutase (Mn‐SOD) activity were significantly increased in ATORVA.ConclusionIn the RVLM of SHRSP, atorvastatin inhibits membrane translocation of Rac1 and NAD (P) H oxidase subunits and upregulates Mn‐SOD activity, which contribute to the inhibition of oxidative stress in the RVLM, protection for neural plasticity and the sympatho‐inhibitory effect.
TAS2R50 genotype and dietary preferences
Authors: Asik Christine , Eny Karen , Herd Sarah , Lee Hyeon Joo , El‐Sohemy Ahmed 
Published: June 2021

The TAS2R50 gene belongs to the TAS2R taste receptor family, which mediate bitter taste perception. The objective of this study was to determine if genetic variation in TAS2R50 is associated with differences in dietary preferences. Individuals (n=967) between the ages of 20 and 29 years completed a food preference checklist to rank their liking/disliking of 24 bitter foods and beverages on a 9‐point scale. Subjects who reported the lowest 3 points were classified as disliking. DNA was isolated from blood samples and genotyped for a polymorphism in TAS2R50 (rs2900554, G>T). In this population, the frequency of the G and T alleles were 36.8% and 63.2%, respectively. The TAS2R50 genotype was strongly associated with different preferences for grapefruit and grapefruit juice. Individuals with the GG genotype were most likely to report disliking grapefruit followed by individuals with the GT and TT genotypes (30.0%, 15.8%, 7.8%; p<0.0001). Similar effects were observed for grapefruit juice (33.3%, 18.7%, 14.9%; p<0.0001). TAS2R50 genotypes were also associated with differences in preference for kale (p=0.008), spinach (p=0.01), turnip (p=0.03) and bitter sweet chocolate (p=0.05). These results indicate that common variations in the TAS2R50 gene are associated with differences in preference for grapefruit and other bitter tasting foods and may explain inter‐individual differences in the consumption of these foods.Grant Funding SourceThe Advanced Foods and Materials Network