Saccharomyces cerevisiae ergosterol biosynthesis, like cholesterol biosynthesis in mammals, is regulated at the transcriptional level by a sterol feedback mechanism. Yeast studies defined a 7-bp consensus sterol-response element (SRE) common to genes involved in sterol biosynthesis and two transcription factors, Upc2 and Ecm22, which direct transcription of sterol biosynthetic genes. The 7-bp consensus SRE is identical to the anaerobic response element, AR1c.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
November 2013
Sustained activation of N-methyl-d-aspartate (NMDA) -type glutamate receptors leads to excitotoxic neuronal death in stroke, brain trauma, and neurodegenerative disorders. Superoxide production by NADPH oxidase is a requisite event in the process leading from NMDA receptor activation to excitotoxic death. NADPH oxidase generates intracellular H(+) along with extracellular superoxide, and the intracellular H(+) must be released or neutralized to permit continued NADPH oxidase function.
View Article and Find Full Text PDFAntimicrob Agents Chemother
September 2014
Incorporation of ground peanut skins (PS) into peanut butter at 1.25%, 2.5%, 3.
View Article and Find Full Text PDFFront Aging Neurosci
September 2013
Silent information regulator 2 proteins (sirtuins or SIRTs) are a group of deacetylases (or deacylases) whose activities are dependent on and regulated by nicotinamide adenine dinucleotide (NAD(+)). Compelling evidence supports that sirtuins play major roles in many aspects of physiology, especially in pathways related to aging - the predominant and unifying risk factor for neurodegenerative diseases. In this review, we highlight the molecular mechanisms underlying the protective effects of sirtuins in neurodegenerative diseases, focusing on protein homeostasis, neural plasticity, mitochondrial function, and sustained chronic inflammation.
View Article and Find Full Text PDFAllosteric conformational changes in antithrombin induced by binding a specific heparin pentasaccharide result in very large increases in the rates of inhibition of factors IXa and Xa but not of thrombin. These are accompanied by CD, fluorescence, and NMR spectroscopic changes. X-ray structures show that heparin binding results in extension of helix D in the region 131-136 with coincident, and possibly coupled, expulsion of the hinge of the reactive center loop.
View Article and Find Full Text PDFBackground: Estrogen-related receptors (ERRs) are orphan nuclear hormone receptors expressed in metabolically active tissues and modulate numerous homeostatic processes. ERRs do not bind the ligand estrogen, but they are able to bind the estrogen response element (ERE) embedded within the ERR response elements (ERREs) to regulate transcription of genes. Previous work has demonstrated that adult mice lacking Errβ have altered metabolism and meal patterns.
View Article and Find Full Text PDFSerpin protein protease inhibitors inactivate their target proteases through a unique mechanism in which a major serpin conformational change, resulting in a 70-Å translocation of the protease from its initial reactive center loop docking site to the opposite pole of the serpin, kinetically traps the acyl-intermediate complex. Although the initial Michaelis and final trapped acyl-intermediate complexes have been well characterized structurally, the intermediate stages involved in this remarkable transformation are not well understood. To better characterize such intermediate steps, we undertook rapid kinetic studies of the FRET and fluorescence perturbation changes of site-specific fluorophore-labeled derivatives of the serpin, α1-protease inhibitor (α1PI), which report the serpin and protease conformational changes involved in transforming the Michaelis complex to the trapped acyl-intermediate complex in reactions with trypsin.
View Article and Find Full Text PDFIn this study, we ask two questions: (1) Is reproductive success independent of parental genetic distance in predominately selfing plants? (2) In the absence of early inbreeding depression, is there substantial maternal and/or paternal variation in reproductive success in natural populations? Seed yield in single pollinations and proportion of seeds sired in mixed pollinations were studied in genetically defined accessions of the predominately selfing plant Arabidopsis thaliana by conducting two diallel crosses. The first diallel was a standard, single pollination design that we used to examine variance in seed yield. The second diallel was a mixed pollination design that utilized a standard pollen competitor to examine variance in proportion of seeds sired.
View Article and Find Full Text PDFIodine-131 (half-life = 8.04 d) is the most widely used radionuclide in medicine for therapeutic purposes. It is excreted by patients and is discharged directly to sewer systems.
View Article and Find Full Text PDFNeurorehabil Neural Repair
July 2014
Background: Effective recovery from functional impairments caused by traumatic brain injury (TBI) requires appropriate rehabilitation therapy. Multiple pathways are involved in secondary injury and recovery suggesting a role for multimodal approaches.
Objective: Here, we examined the efficacy of the anti-inflammatory agent minocycline and botulinum toxin (botox)-induced limb constraint with structured physical therapy, delivered alone or in combination, after a severe TBI produced by a controlled cortical impact in rats.
Purpose: To assess North Carolina pharmacists' level of support for expanded authority to administer human papillomavirus (HPV) vaccines to identify concerns/benefits about expanded authority and to understand what factors predict support for expanded authority.
Method: A 16-item electronic survey was e-mailed to all the pharmacists registered with the North Carolina Board of Pharmacy (n = 9502) between January and February 2011 (1600 pharmacists responded). The survey assessed HPV knowledge, level of support for expanded authority, and comfort level of HPV vaccine administration.
Background: In human oocytes, as in other mammalian ova, there is a significant variation in the pregnancy potential, with approximately 20% of oocyte-sperm meetings resulting in pregnancies. This frequency of successful fertilization decreases as the oocytes age. This low proportion of fruitful couplings appears to be influenced by changes in mitochondrial structure and function.
View Article and Find Full Text PDFMatriptase, a membrane-associated serine protease, plays an essential role in epidermal barrier function through activation of the glycosylphosphatidylinositol (GPI)-anchored serine protease prostasin. The matriptase-prostasin proteolytic cascade is tightly regulated by hepatocyte growth factor activator inhibitor (HAI)-1 such that matriptase autoactivation and prostasin activation occur simultaneously and are followed immediately by the inhibition of both enzymes by HAI-1. However, the mechanisms whereby matriptase acts on extracellular substrates remain elusive.
View Article and Find Full Text PDFC1q/TNF-related protein 13 (CTRP13), a hormone secreted by adipose tissue (adipokines), helps regulate glucose metabolism in peripheral tissues. We previously reported that CTRP13 expression is increased in obese and hyperphagic leptin-deficient mice, suggesting that it may modulate food intake and body weight. CTRP13 is also expressed in the brain, although its role in modulating whole-body energy balance remains unknown.
View Article and Find Full Text PDFNF-κB is a transcription factor that integrates pro-inflammatory and pro-survival responses in diverse cell types. The activity of NF-κB is regulated in part by acetylation of its p65 subunit at lysine 310, which is required for transcription complex formation. De-acetylation at this site is performed by sirtuin 1(SIRT1) and possibly other sirtuins in an NAD(+) dependent manner, such that SIRT1 inhibition promotes NF-κB transcriptional activity.
View Article and Find Full Text PDFAm J Physiol Regul Integr Comp Physiol
June 2013
Disruption of finely coordinated neuropeptide signals in the hypothalamus can result in altered food intake and body weight. We identified neuron-derived neurotrophic factor (NENF) as a novel secreted protein through a large-scale screen aimed at identifying novel secreted hypothalamic proteins that regulate food intake. We observed robust Nenf expression in hypothalamic nuclei known to regulate food intake, and its expression was altered under the diet-induced obese (DIO) condition relative to the fed state.
View Article and Find Full Text PDFSustained activation of neuronal N-methly D-aspartate (NMDA)-type glutamate receptors leads to excitotoxic cell death in stroke, trauma, and neurodegenerative disorders. Excitotoxic neuronal death results in part from superoxide produced by neuronal NADPH oxidase (NOX2), but how NMDA receptors are coupled to neuronal NOX2 activation is not well understood. Here, we identify a signaling pathway coupling NMDA receptor activation to NOX2 activation in primary neuron cultures.
View Article and Find Full Text PDFIodine-131 (t1/2=8.04 d) is administered to patients for treatment of thyroid disorders, excreted by patients and discharged to surface waters via sewage effluent. Radionuclides generally behave like their stable analogs; therefore, medically-derived (131)I is useful as a transport-reaction tracer of anthropogenic inputs and the aquatic biogeochemistry of iodine.
View Article and Find Full Text PDFEstrogen-related receptors (ERRs) α, β and γ are orphan nuclear hormone receptors with no known ligands. Little is known concerning the role of ERRβ in energy homeostasis, as complete ERRβ-null mice die mid-gestation. We generated two viable conditional ERRβ-null mouse models to address its metabolic function.
View Article and Find Full Text PDFSince its inception, osteopathic medicine has sought to identify the mechanical causes of disease and to understand the body's structure-function relationship. Research conducted during the past 25 years has demonstrated that the architectural principles of tensegrity can be applied to biological organisms (termed biotensegrity) and that these principles can demonstrate the mechanical structure-function relationship at all size scales in the human body. Further, biotensegrity at the cellular level allows the cell to mechanically sense its environment and convert mechanical signals into biochemical changes.
View Article and Find Full Text PDFExcitotoxic neuronal death is mediated in part by NMDA receptor-induced activation of NOX2, an enzyme that produces superoxide and resultant oxidative stress. It is not known, however, whether the superoxide is generated in the intracellular space, producing oxidative stress in the neurons responding to NMDA receptor activation, or in the extracellular space, producing oxidative stress in neighboring cells. We evaluated these alternatives by preparing cortical neuron cultures from p47(phox-/-) mice, which are unable to form a functional NOX2 complex, and transfecting the cultures at low density with GFP-tagged p47(phox) to reconstitute NOX2 activity in widely scattered neurons.
View Article and Find Full Text PDF