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Full-Text Articles in Physiology

Hydroxychloroquine Prophylaxis For Covid-19, David D. Busath Oct 2020

Hydroxychloroquine Prophylaxis For Covid-19, David D. Busath

Faculty Publications

It is common in medicine that simple, inexpensive remedies are held hostage to medical prejudice, financial or political interest, and legal precedent. The purpose of this review is to take the point of view of the victims of COVID-19 and address whether scientific information, including randomized-control trials, can answer whether the hydroxychloroquine should be dispensed for those testing positive and their immediate recent contacts at the point of testing. Although the FDA in the United States is yet to be convinced, the demonstration of positive effects in clinical trials cannot be ignored and there is a large amount of information …


Mechanism Of Inhibition Of Influenza A Virus M2 Proton Channel, Douglas Randall Bretzing, Victoria Man-Fung Burr May 2012

Mechanism Of Inhibition Of Influenza A Virus M2 Proton Channel, Douglas Randall Bretzing, Victoria Man-Fung Burr

Faculty Publications

The influenza A virus integral membrane protein, M2, is a proton-conducting channel. The ability of influenza A virus to unpack its genome, replicate, and infect its host is contingent upon the M2-mediated acidification of the viral interior. The antiviral drugs amantadine and rimantadine were previously effective in blocking proton influx through M2; however, mutations in the proton channel have rendered these drugs ineffective. Multiple models for the inhibiting mechanism of the adamantane drugs have been hypothesized. In an attempt to better understand the mechanism of M2 inhibition, and ultimately to assist in the development of a replacement M2-targeting antiviral drug, …


Afm Study Of Structural Changes In Supported Planar Dppc Bilayers Containing General Anesthetic Isofluorane (Plus Additional Afm Experiments), Chad Mckell, Hiram Conley, David D. Busath Jan 2010

Afm Study Of Structural Changes In Supported Planar Dppc Bilayers Containing General Anesthetic Isofluorane (Plus Additional Afm Experiments), Chad Mckell, Hiram Conley, David D. Busath

Faculty Publications

Atomic force microscopy (AFM) is a remarkable tool for assessing the structural properties of supported lipid planar bilayers under different physiological conditions. Previous work has shown that incorporation of anesthetics into artificial lipid bilayers results in domain formation [1], destruction of lipid aggregates and patches [2], anesthetic-lipid mixed micelle formation [2], and the development of interdigitated phases of reduced thickness compared to anesthetic-free bilayers [3]. In particular, these interdigitated phases are suspected to affect the structure and activity of membrane proteins, such as ion channels, and thus further research with proteinembedded bilayers exposed to anesthetics could reveal the mechanism responsible …


Timing Of Supplementation Of Selenium And Isoflavones Determines Prostate Cancer Risk Factor Reduction In Rats, Merrill J. Christensen, Jessica R. Tolman, Edwin D. Lephart, Dennis L. Eggett, Kenneth Setchell Nov 2008

Timing Of Supplementation Of Selenium And Isoflavones Determines Prostate Cancer Risk Factor Reduction In Rats, Merrill J. Christensen, Jessica R. Tolman, Edwin D. Lephart, Dennis L. Eggett, Kenneth Setchell

Faculty Publications

High dietary intake of selenium or isoflavones reduces risk factors for prostate cancer. We tested whether combined supplementation of these two dietary components would reduce prostate cancer risk factors in rats more than supplementation of each component individually. Methods Male Noble rat pups were exposed from conception to diets containing an adequate (0.33-0.45 mg/kg diet) or high (3.33-3.45 mg/kg) concentration of selenium as Se-methylselenocysteine and a low (10 mg/kg) or high (600 mg/kg) level of isoflavones in a 2 x 2 factorial design. Pups consumed their respective diets until sacrifice at 35, 100, or 200 days. Male Noble rat breeders, …


Avpv Neurons Containing Estrogen Receptor-Beta In Adult Male Rats Are Influenced By Soy Isoflavones, Edwin D. Lephart, Lihong H. Bu Feb 2007

Avpv Neurons Containing Estrogen Receptor-Beta In Adult Male Rats Are Influenced By Soy Isoflavones, Edwin D. Lephart, Lihong H. Bu

Faculty Publications

Background Isoflavones, the most abundant phytoestrogens in soy foods, are structurally similar to 17beta-estradiol. It is known that 17beta-estradiol induces apoptosis in anteroventral periventricular nucleus (AVPV) in rat brain. Also, there is evidence that consumption of soy isoflavones reduces the volume of AVPV in male rats. Therefore, in this study, we examined the influence of dietary soy isoflavones on apoptosis in AVPV of 150 day-old male rats fed either a soy isoflavone-free diet (Phyto-free) or a soy isoflavone-rich diet (Phyto-600). Results: The occurrence of apoptosis in AVPV was examined by TUNEL staining. The incidence of apoptosis was about 10 times …


Influences Of Dietary Soy Isoflavones On Metabolism But Not Nociception And Stress Hormone Responses In Ovariectomized Female Rats, Edwin D. Lephart, Lihong H. Bu, Kenneth Setchell Oct 2005

Influences Of Dietary Soy Isoflavones On Metabolism But Not Nociception And Stress Hormone Responses In Ovariectomized Female Rats, Edwin D. Lephart, Lihong H. Bu, Kenneth Setchell

Faculty Publications

Isoflavones, the most abundant phytoestrogens in soy foods, are structurally similar to 17beta-estradiol. Few studies have examined the nociception and stress hormone responses after consumption of soy isoflavones. Methods: In this study, ovariectomized (OVX) female Long-Evans rats were fed either an isoflavone-rich diet (Phyto-600) or an isoflavone-free diet (Phyto-free). We examined the effects of soy isoflavones on metabolism by measuring body weights, food/water intake, adipose tissue weights as well as serum leptin levels. Also, circulating isoflavone levels were quantified. During chemically induced estrous, nociceptive thresholds were recorded. Then, the animals were subjected to a stressor and stress hormone levels were …


Dietary Isoflavones Alter Regulatory Behaviors, Metabolic Hormones And Neuroendocrine Function In Long-Evans Male Rats, Edwin D. Lephart, James P. Proter, Lihong H. Bu, Trent D. Lund, Kenneth Setchell, Gina Ramoz, William R. Crowley Dec 2004

Dietary Isoflavones Alter Regulatory Behaviors, Metabolic Hormones And Neuroendocrine Function In Long-Evans Male Rats, Edwin D. Lephart, James P. Proter, Lihong H. Bu, Trent D. Lund, Kenneth Setchell, Gina Ramoz, William R. Crowley

Faculty Publications

Phytoestrogens derived from soy foods (or isoflavones) have received prevalent usage due to their 'health benefits' of decreasing: a) age-related diseases, b) hormone-dependent cancers and c) postmenopausal symptoms. However, little is known about the influence of dietary phytoestrogens on regulatory behaviors, such as food and water intake, metabolic hormones and neuroendocrine parameters. This study examined important hormonal and metabolic health issues by testing the hypotheses that dietary soy-derived isoflavones influence: 1) body weight and adipose deposition, 2) food and water intake, 3) metabolic hormones (i.e., leptin, insulin, T3 and glucose levels), 4) brain neuropeptide Y (NPY) levels, 5) heat production …


Androgen Receptor Expression In The Rat Prostate Is Down-Regulated By Dietary Phytoestrogens, Edwin D. Lephart, Trent D. Lund, Daniel J. Munson, Herman Aldercreutz, Robert J. Handa Jan 2004

Androgen Receptor Expression In The Rat Prostate Is Down-Regulated By Dietary Phytoestrogens, Edwin D. Lephart, Trent D. Lund, Daniel J. Munson, Herman Aldercreutz, Robert J. Handa

Faculty Publications

Background- It is well established that the growth of the prostate gland is a hormone-dependent phenomenon involving both androgenic and estrogenic control. Proliferation of prostate cells is, at least in part, under control of estrogen receptor beta (ER-beta). Phytoestrogens bind ER-beta with high affinity and therefore may have antiproliferative effects in the prostate. Methods- The prostates of male Long-Evans rats fed a diet high in phytoestrogens (Phyto-600) or very low levels of phytoestrogens (Phyto-free) were analyzed to determine the impact of dietary phytoestrogens on prostate weight and androgen receptor (AR) expression in the prostate. Results- Dietary phytoestrogens significantly decreased post-pubertal …


Manipulation Of Prenatal Hormones And Dietary Phytoestrogens During Adulthood Alter The Sexually Dimorphic Expression Of Visual Spatial Memory, Edwin D. Lephart, Trent D. Lund Dec 2001

Manipulation Of Prenatal Hormones And Dietary Phytoestrogens During Adulthood Alter The Sexually Dimorphic Expression Of Visual Spatial Memory, Edwin D. Lephart, Trent D. Lund

Faculty Publications

In learning and memory tasks, requiring visual spatial memory (VSM), males exhibit higher performance levels compared to females (a difference attributed to sex steroid hormonal influences). Based upon the results from our companion investigation, this study examined the influence of prenatal sex steroid hormone manipulations on VSM in adulthood, as assessed in the radial arm maze. Additionally, the influence of dietary soy phytoestrogens (i.e., the presence of high or low estrogen-like compounds present in the animal's diet) on VSM was examined in combination with the prenatal hormonal manipulations. Results: Radial arm maze performance on a phytoestrogen-rich diet: 1) females treated …


Visual Spatial Memory Is Enhanced In Female Rats (But Inhibited In Males) By Dietary Soy Phytoestrogens, Edwin D. Lephart, Trent D. Lund, Timothy W. West, Lilyan Y. Tian, Lihong H. Bu, Daniel L. Simmons, Kenneth Setchell, Herman Adlercreutz Dec 2001

Visual Spatial Memory Is Enhanced In Female Rats (But Inhibited In Males) By Dietary Soy Phytoestrogens, Edwin D. Lephart, Trent D. Lund, Timothy W. West, Lilyan Y. Tian, Lihong H. Bu, Daniel L. Simmons, Kenneth Setchell, Herman Adlercreutz

Faculty Publications

In learning and memory tasks, requiring visual spatial memory (VSM), males exhibit superior performance to females (a difference attributed to the hormonal influence of estrogen). This study examined the influence of phytoestrogens (estrogen-like plant compounds) on VSM, utilizing radial arm-maze methods to examine varying aspects of memory. Additionally, brain phytoestrogen, calbindin (CALB), and cyclooxygenase-2 (COX-2) levels were determined. Results: Female rats receiving lifelong exposure to a high-phytoestrogen containing diet (Phyto-600) acquired the maze faster than females fed a phytoestrogen-free diet (Phyto-free); in males the opposite diet effect was identified. In a separate experiment, at 80 days-of-age, animals fed the Phyto-600 …


Sodium Flux Ratio In Voltage-Clamped Squid Giant Axons, David D. Busath, Ted Begenisich Jan 1981

Sodium Flux Ratio In Voltage-Clamped Squid Giant Axons, David D. Busath, Ted Begenisich

Faculty Publications

The sodium flux ratio across the axolemma of internally perfused, voltage-clamped giant axons of Loligo pealei has been measured at various membrane potentials. The flux ratio exponent obtained from these measurements was about unity and independent of membrane voltage over the 50 mV range from about -20 to +30 mV. These results, combined with previous measurements of ion permeation through sodium channels, show that the sodium channel behaves like a multi-ion pore with two ion binding sites that are rarely simultaneously occupied by sodium.


Two-, Three-, And Four-Particle Spatial Correlations Among Tertiary Cosmic Ray Muons, David D. Busath, R O. Stevenson Jan 1971

Two-, Three-, And Four-Particle Spatial Correlations Among Tertiary Cosmic Ray Muons, David D. Busath, R O. Stevenson

Faculty Publications

Showers of muons which result from interactions of primary cosmic rays high in the atmosphere appear deep underground as bundles of nearly parallel muons. For threshold energies of 1 TeV and arrival zenith angles of 45 degrees, those events having a small mean number of muons are described by a power law distribution in shower size having an exponent of ≅ -3.7 and a radial density distribution that decreases with distance R from the shower axis a little less rapidly than exp(-R/5.4 m). Comparison of new data on four muon spatial correlations in terms of the same phenomenology with data …