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Angiotensin II induces membrane trafficking of natively-expressed Transient Receptor Potential vanilloid type 4 channels in hypothalamic 4B cells.

Angiotensin II induces membrane trafficking of natively-expressed Transient Receptor Potential vanilloid type 4 channels in hypothalamic 4B cells.

Am J Physiol Regul Integr Comp Physiol. 2014 Jul 30;

Authors: Saxena A, Bachelor M, Park YH, Carreno FR, Nedungadi TP, Cunningham JT

Abstract
Transient receptor potential vanilloid family type 4 (TRPV4) channels are expressed in central neuroendocrine neurons and have been shown to be polymodal in other systems. We previously reported that, in rodent a model of dilutional hyponatremia associated with hepatic cirrhosis, TRPV4 expression is increased in lipid rafts from the hypothalamus and that this effect may be angiotensin dependent. In this study, we utilized the immortalized neuroendocrine rat hypothalamic 4B cell line to more directly test the effects of angiotensin II (Ang II) on TRPV4 expression and function. Our results demonstrate the expression of transcripts for SRY (male genotype), AVP, CRF, TRPV4, and Ang II type 1a and 1b receptor in 4B cells. After a 1 hour incubation in Ang II (100 nM), 4B cells showed increased TRPV4 abundance in the plasma membrane fraction and this effect was prevented by the Ang II type 1 receptor antagonist, Losartan (1 µM) , and by a Src kinase inhibitor, PP2 (10 µM). Radiometric calcium imaging experiments demonstrated that Ang II incubation potentiated TRPV4 agonist (GSK 1016790A, 20 nM) induced calcium influx (Control 18.4 ± 2.8% n=5 and Ang II 80.5 ± 2.4% n=5). This Ang II induced increase in calcium influx was also blocked by 1 µM Losartan and 10 µM PP2 (Losartan 26.4 ± 3.8% n=5 and PP2 19.7 ± 3.9% n=5). Our data suggests that Ang II can increase TRPV4 channel membrane expression in 4B cells through its action on AT1R involving a Src kinase pathway.

PMID: 25080500 [PubMed - as supplied by publisher]

Resting sympathetic baroreflex sensitivity in subjects with low and high tolerance to central hypovolemia induced by lower body negative pressure.

Resting sympathetic baroreflex sensitivity in subjects with low and high tolerance to central hypovolemia induced by lower body negative pressure.

Front Physiol. 2014;5:241

Authors: Hinojosa-Laborde C, Ryan KL, Rickards CA, Convertino VA

Abstract
Central hypovolemia elicited by orthostasis or hemorrhage triggers sympathetically-mediated baroreflex responses to maintain organ perfusion; these reflexes are less sensitive in patients with orthostatic intolerance, and during conditions of severe blood loss, may result in cardiovascular collapse (decompensatory or circulatory shock). The ability to tolerate central hypovolemia is variable and physiological factors contributing to tolerance are emerging. We tested the hypothesis that resting muscle sympathetic nerve activity (MSNA) and sympathetic baroreflex sensitivity (BRS) are attenuated in male and female subjects who have low tolerance (LT) to central hypovolemia induced by lower body negative pressure (LBNP). MSNA and diastolic arterial pressure (DAP) were recorded in 47 human subjects who subsequently underwent LBNP to tolerance (onset of presyncopal symptoms). LT subjects experienced presyncopal symptoms prior to completing LBNP of -60 mm Hg, and subjects with high tolerance (HT) experienced presyncopal symptoms after completing LBNP of -60 mm Hg. Contrary to our hypothesis, resting MSNA burst incidence was not different between LT and HT subjects, and was not related to time to presyncope. BRS was assessed as the slope of the relationship between spontaneous fluctuations in DAP and MSNA during 5 min of supine rest. MSNA burst incidence/DAP correlations were greater than or equal to 0.5 in 37 subjects (LT: n = 9; HT: n = 28), and BRS was not different between LT and HT (-1.8 ± 0.3 vs. -2.2 ± 0.2 bursts·(100 beats)(-1) ·mm Hg(-1), p = 0.29). We conclude that tolerance to central hypovolemia is not related to either resting MSNA or sympathetic BRS.

PMID: 25071587 [PubMed]

Lymphatic pump treatment repeatedly enhances the lymphatic and immune systems.

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Lymphatic pump treatment repeatedly enhances the lymphatic and immune systems.

Lymphat Res Biol. 2013 Dec;11(4):219-26

Authors: Schander A, Padro D, King HH, Downey HF, Hodge LM

Abstract
BACKGROUND: Osteopathic practitioners utilize manual therapies called lymphatic pump techniques (LPT) to treat edema and infectious diseases. While previous studies examined the effect of a single LPT treatment on the lymphatic system, the effect of repeated applications of LPT on lymphatic output and immunity has not been investigated. Therefore, the purpose of this study was to measure the effects of repeated LPT on lymphatic flow, lymph leukocyte numbers, and inflammatory mediator concentrations in thoracic duct lymph (TDL).
METHODS AND RESULTS: The thoracic ducts of five mongrel dogs were cannulated, and lymph samples were collected during pre-LPT, 4 min of LPT, and 2 hours post-LPT. A second LPT (LPT-2) was applied after a 2 hour rest period. TDL flow was measured, and TDL were analyzed for the concentration of leukocytes and inflammatory mediators. Both LPT treatments significantly increased TDL flow, leukocyte count, total leukocyte flux, and the flux of interleukin-8 (IL-8), keratinocyte-derived chemoattractant (KC), nitrite (NO2(-)), and superoxide dismutase (SOD). The concentration of IL-6 increased in lymph over time in all experimental groups; therefore, it was not LPT dependent.
CONCLUSION: Clinically, it can be inferred that LPT at a rate of 1 pump per sec for a total of 4 min can be applied every 2 h, thus providing scientific rationale for the use of LPT to repeatedly enhance the lymphatic and immune system.

PMID: 24364845 [PubMed - indexed for MEDLINE]

Monitoring retinal morphologic and functional changes in mice following optic nerve crush.

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Monitoring retinal morphologic and functional changes in mice following optic nerve crush.

Invest Ophthalmol Vis Sci. 2014;55(6):3766-74

Authors: Liu Y, McDowell CM, Zhang Z, Tebow HE, Wordinger RJ, Clark AF

Abstract
PURPOSE: We characterized the morphologic and functional changes in optic nerve crushed mice and evaluated electroretinogram (ERG) responses as tools to monitor retinal ganglion cell (RGC) dysfunction.
METHODS: We performed optic nerve crush (ONC) unilaterally in adult BALB/cJ mice. The neuronal loss in the RGC layer (GCL) and superior colliculus (SC) was determined by Nissl staining. Retinal thickness was assessed by spectral-domain optical coherence tomography (SD-OCT) imaging. Retinal function was determined by pattern ERG and full-field flash ERG. Responses of pattern ERG, positive scotopic threshold response (pSTR), scotopic oscillatory potentials (OPs), and photopic negative response (PhNR) were analyzed.
RESULTS: The ONC induced progressive neuronal loss in GCL and contralateral SC starting from 7 and 28 days following ONC, respectively. A linear correlation was observed between combined thickness of nerve fiber layer (NFL), GCL, and inner plexiform layer (IPL) imaged by SD-OCT and cell numbers in GCL. Only half of the normal BALB/cJ mice exhibited pattern ERG response, which was smaller and later compared to C57BL/6J mice. The ONC reduced pattern ERG and pSTR, but the reduction of pattern ERG was earlier than pSTR, preceding the anatomical cell loss in the GCL. The PhNR and scotopic OPs were not affected by ONC.
CONCLUSIONS: The SD-OCT and ERG can be used to monitor noninvasively retinal morphologic and functional changes induced by ONC. Pattern ERG and pSTR are able to detect early RGC dysfunction, but pattern ERG exhibits higher sensitivity. Our results support the use of these tools in studies using the mouse ONC model.

PMID: 24854856 [PubMed - indexed for MEDLINE]

Using modified approaches on marginal regression analysis of longitudinal data with time-dependent covariates

Latest UNTHSC Articles in Scopus - Thu, 07/31/2014 - 4:05pm
Author(s):Zhou, Y. | Lefante, J. | Rice, J. | Chen, S.
Publication year: 2014
Journal / Book title: Statistics in Medicine

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PTEN degradation after ischemic stroke: A double-edged sword

Latest UNTHSC Articles in Scopus - Thu, 07/31/2014 - 4:05pm
Author(s):Li, W. | Huang, R. | Chen, Z. | Yan, L.-J. | Simpkins, J.W. | Yang, S.-H.
Publication year: 2014
Journal / Book title: Neuroscience

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Application of screening experimental designs to assess chromatographic isotope effect upon isotope-coded derivatization for quantitative liquid chromatography-mass spectrometry

Latest UNTHSC Articles in Scopus - Thu, 07/31/2014 - 4:05pm
Author(s):Szarka, S. | Prokai-Tatrai, K. | Prokai, L.
Publication year: 2014
Journal / Book title: Analytical Chemistry

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ERK5/KLF4 signaling as a common mediator of the neuroprotective effects of both nerve growth factor and hydrogen peroxide preconditioning

Latest UNTHSC Articles in Scopus - Thu, 07/31/2014 - 4:05pm
Author(s):Su, C. | Sun, F. | Cunningham, R.L. | Rybalchenko, N. | Singh, M.
Publication year: 2014
Journal / Book title: AGE

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Astrocyte elevated gene-1 is a novel modulator of HIV-1-associated neuroinflammation via regulation of nuclear factor-κB signaling and excitatory amino acid transporter-2 repression

Latest UNTHSC Articles in Scopus - Thu, 07/31/2014 - 4:05pm
Author(s):Vartak-Sharma, N. | Gelman, B.B. | Joshi, C. | Borgamann, K. | Ghorpade, A.
Publication year: 2014
Journal / Book title: Journal of Biological Chemistry

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The Association between Patient-Centered Attributes of Care and Patient Satisfaction

Latest UNTHSC Articles in Scopus - Thu, 07/31/2014 - 4:05pm
Author(s):Tak, H. | Ruhnke, G.W. | Shih, Y.-C.T.
Publication year: 2014
Journal / Book title: The Patient - Patient-Centered Outcomes Research

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Evidence of brain tumor stem progenitor-like cells with low proliferative capacity in human benign pituitary adenoma

Latest UNTHSC Articles in Scopus - Thu, 07/31/2014 - 4:05pm
Author(s):Chen, L. | Ye, H. | Wang, X. | Tang, X. | Mao, Y. | Zhao, Y. | Wu, Z. | Mao, X.O. | Xie, L. | Jin, K. | Yao, Y.
Publication year: 2014
Journal / Book title: Cancer Letters

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Total Cholesterol and Neuropsychiatric Symptoms in Alzheimer's Disease: The Impact of Total Cholesterol Level and Gender

Latest UNTHSC Articles in Scopus - Thu, 07/31/2014 - 4:05pm
Author(s):Hall, J.R. | Wiechmann, A.R. | Johnson, L.A. | Edwards, M. | Barber, R.C. | Cunningham, R. | Singh, M. | O'Bryant, S.E.
Publication year: 2014
Journal / Book title: Dementia and Geriatric Cognitive Disorders

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The role of 5-HT2A, 5-HT2C and mGlu2 receptors in the behavioral effects of tryptamine hallucinogens N,N-dimethyltryptamine and N,N-diisopropyltryptamine in rats and mice

Latest UNTHSC Articles in Scopus - Thu, 07/31/2014 - 4:05pm
Author(s):Carbonaro, T.M. | Eshleman, A.J. | Forster, M.J. | Cheng, K. | Rice, K.C. | Gatch, M.B.
Publication year: 2014
Journal / Book title: Psychopharmacology

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Projection target-specific action of nicotine in the caudal nucleus of the solitary tract

Latest UNTHSC Articles in Scopus - Thu, 07/31/2014 - 4:05pm
Author(s):Feng, L. | Uteshev, V.V.
Publication year: 2014
Journal / Book title: Journal of Neuroscience Research

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Identification and characterization of the spiruchostatin biosynthetic gene cluster enable yield improvement by overexpressing a transcriptional activator

Latest UNTHSC Articles in Scopus - Thu, 07/31/2014 - 4:05pm
Author(s):Potharla, V.Y. | Wang, C. | Cheng, Y.-Q.
Publication year: 2014
Journal / Book title: Journal of Industrial Microbiology & Biotechnology

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Clinical response and relapse in patients with chronic low back pain following osteopathic manual treatment: Results from the OSTEOPATHIC Trial

Latest UNTHSC Articles in Scopus - Thu, 07/31/2014 - 4:05pm
Author(s):Licciardone, J.C. | Aryal, S.
Publication year: 2014
Journal / Book title: Manual Therapy

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Role of deuterium desorption kinetics on the thermionic emission properties of polycrystalline diamond films with respect to kinetic isotope effects

Latest UNTHSC Articles in Scopus - Thu, 07/31/2014 - 4:05pm
Author(s):Paxton, W.F. | Brooks, M.M. | Howell, M. | Tolk, N. | Kang, W.P. | Davidson, J.L.
Publication year: 2014
Journal / Book title: Journal of Applied Physics

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Extracellular pH modulates GABAergic neurotransmission in rat hypothalamus

Latest UNTHSC Articles in Scopus - Thu, 07/31/2014 - 4:05pm
Author(s):Chen, Z.-L. | Huang, R.-Q.
Publication year: 2014
Journal / Book title: Neuroscience

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Enhanced toxicity of cisplatin with chemosensitizer phenethyl isothiocyanate toward non-small cell lung cancer cells when delivered in liposomal nanoparticles

Latest UNTHSC Articles in Scopus - Thu, 07/31/2014 - 4:05pm
Author(s):Yang, Y.-T. | Shi, Y. | Jay, M. | Di Pasqua, A.J.
Publication year: 2014
Journal / Book title: Chemical Research in Toxicology

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Autonomic neural control of heart rate during dynamic exercise: Revisited

Latest UNTHSC Articles in Scopus - Thu, 07/31/2014 - 4:05pm
Author(s):White, D.W. | Raven, P.B.
Publication year: 2014
Journal / Book title: Journal of Physiology

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