EmrE is a small H+-coupled multidrug transporter in Escherichia coli. Claims have been made for an antiparallel topology of this homodimeric protein. However, our own biochemical studies performed with detergent-solubilized purified protein support a parallel topology of the protomers.
View Article and Find Full Text PDFObjective: In order to test the hypothesis that upper airway resistance syndrome (UARS) is merely an extension of the pathophysiology of obstructive sleep apnea/hypopnea (OSA/H) to less severe pharyngeal collapse during sleep, we compared the severity of hypersomnolence and the prevalence of insomnia in UARS patients to the patterns observed for OSA/H patients. Our goal was to determine whether the severity of hypersomnolence and the prevalence of insomnia observed in UARS patients could have been predicted from the patterns observed among OSA/H patients.
Methods: We performed a retrospective study of a large consecutive patient series evaluated at an academic sleep disorders center, including 220 OSA/H patients and 137 UARS patients.
Patients with elevated low-density lipoprotein (LDL) cholesteral levels are at high risk of cardiovascular events but are often undertreated and fail to achieve lipid goals. This open-label, noncomparative, multicenter study assessed efficacy and safety of rosuvastatin 40 mg for < or =96 weeks in 1,380 patients with severe hypercholesterolemia, including heterozygous familial hypercholesterolemia. Patients > or =18 years old with fasting LDL cholesterol > or =190 and < or =260 mg/dl and triglycerides <400 mg/dl entered a 6-week dietary lead-in, before receiving rosuvastatin 40 mg for 48 weeks.
View Article and Find Full Text PDFThis study examined televised anti-smoking advertisements that were designed to discourage adult and teen smoking. A content analysis of 399 television advertisements catalogued in the Media Campaign Resource Center (MCRC) database were evaluated to determine (a) whether the advertising content reflected core health communication theories used in the design of health campaign messages to change behavior and (b) the affective presentation of tobacco-control advertisements aimed to decrease smoking. The results revealed that anti-smoking advertising relied overwhelmingly on appeals to attitudes.
View Article and Find Full Text PDFIntroduction: Recently, human studies using exposure therapy to treat anxiety have demonstrated that pretreatment with D-cycloserine (DCS) enhances fear reduction in anxiety disorders. However, the underlying brain mechanisms mediating this fear reduction have yet to be determined.
Methods: The effects of orally administered DCS on amygdala activity during the processing of repeated facial expressions were examined in this double-blind study.
Neuroimaging studies using angry or contemptuous human facial photographic stimuli have suggested amygdala hyper-responsivity in social anxiety disorder (SAD). We sought to determine if an angry "schematic face" (simple line drawing) would evoke exaggerated amygdalar responses in SAD patients compared with healthy control (HC) subjects. Angry, happy, and neutral schematic faces were overtly presented to matched cohorts of 11 SAD and 11 HC subjects for passive viewing, whereas brain functional magnetic resonance imaging signal was measured at 1.
View Article and Find Full Text PDFLower-extremity trauma is an uncommon but reported cause of sciatic nerve injury in children and adolescents. Failure to identify sciatic neuropathy after traumatic injury to the lower extremity may lead to the delayed institution of neuropathic pharmacotherapy, electrodiagnostic testing, physical therapy, and increased risk for the development of complex regional pain syndrome. This article presents a case of an adolescent male with neuropathic pain and weakness in the right lower extremity after traumatic injury.
View Article and Find Full Text PDFIn a large randomized trial of statin therapy in patients of South-Asian origin with hypercholesterolemia, 740 patients in the United States and Canada received 6 weeks of treatment with rosuvastatin 10 or 20 mg or atorvastatin 10 or 20 mg. A total of 485 patients (66%) were categorized as being at high risk of coronary heart disease and had a National Cholesterol Education Program Adult Treatment Panel III treatment goal of low-density lipoprotein (LDL) cholesterol <100 mg/dl (<2.6 mmol/L).
View Article and Find Full Text PDFWe investigated the effects of chronic nicotine on alpha6- and beta3-containing nicotinic acetylcholine receptors (nAChRs) in two rat brain regions using three methodological approaches: radioligand binding, immunoprecipitation, and nicotine-stimulated synaptosomal release of dopamine. Nicotine was administered by osmotic minipumps for 2 weeks. Quantitative autoradiography with [(125)I]alpha-conotoxin MII to selectively label alpha6(*) nAChRs showed a 28% decrease in binding in the striatum but no change in the superior colliculus.
View Article and Find Full Text PDFTrichotillomania (TTM) may be related to obsessive-compulsive disorder (OCD) and other neuropsychiatric conditions characterized by cortico-striatal dysfunction. Functional imaging studies of OCD using an implicit learning task have found abnormalities in striatal and hippocampal activation. The current study investigated whether similar abnormalities occur in TTM.
View Article and Find Full Text PDFUncultivated bacteria associated with the degradation of pyrene in a bioreactor treating soil contaminated with polycyclic aromatic hydrocarbons (PAH) were identified by DNA-based stable-isotope probing (SIP) and quantified by real-time quantitative PCR. Most of the 16S rRNA gene sequences recovered from (13)C-enriched DNA fractions clustered phylogenetically within three separate groups of beta- and gamma-Proteobacteria unassociated with described genera and were designated "Pyrene Groups 1, 2 and 3". One recovered sequence was associated with the Sphingomonas genus.
View Article and Find Full Text PDFButadiene (BD) metabolism shows gender, species and concentration dependency, making the extrapolation of animal results to humans complex. BD is metabolized mainly by cytochrome P450 2E1 to three epoxides, 1,2-epoxy-3-butene (EB), 1,2;3,4-diepoxybutane (DEB) and 1,2-epoxy-butanediol (EB-diol). For accurate risk assessment it is important to elucidate species differences in the internal formation of the individual epoxides in order to assign the relative risks associated with their different mutagenic potencies.
View Article and Find Full Text PDFScand J Work Environ Health
June 2006
Objectives: This study describes the development and evaluation of a method for sampling layers of the stratum corneum for the quantitation of dermal exposure to 1,6-hexamethylene diisocyanate (HDI).
Methods: HDI deposited on skin was collected by the removal of stratum corneum with adhesive tape, derivatized with 1-(2-methoxyphenyl)piperazine, and quantitated as the urea derivative (HDIU) by liquid chromatography-mass spectrometry (LC-MS). This LC-MS method was tested by analyzing tape spiked with HDI-containing products, then applied to tape samples collected from the skin of an auto-body shop worker exposed to polyurethane paint aerosols.
trans-2-Hexenal is an alpha,beta-unsaturated aldehyde to which humans are exposed daily in small amounts. Hexenal has demonstrated mutagenicity and genotoxicity in vitro and reacts with deoxyguanosine to form diastereomeric hexenal-derived exocyclic 1,N(2)-propanodeoxyguanosine (Hex-PdG) adducts. A highly sensitive and specific method for the measurement of Hex-PdG in DNA has not previously been available.
View Article and Find Full Text PDFThe nucleobase guanine was oxidized with dimethyldioxirane (DMDO) to explore the role of epoxidizing agents in oxidative DNA damage. Treatment of guanine with 10% molar excess DMDO in aqueous solution at 0 degrees C and pH 7.5 followed by workup under mild conditions gave 5-carboxamido-5-formamido-2-iminohydantoin (1) as the sole isolable product in 71% yield.
View Article and Find Full Text PDFThe catalytic cycle intermediates of heme peroxidases, known as compounds I and II, have been of long standing interest as models for intermediates of heme proteins, such as the terminal oxidases and cytochrome P450 enzymes, and for non-heme iron enzymes as well. Reports of resonance Raman signals for compound I intermediates of the oxo-iron(IV) porphyrin pi-cation radical type have been sometimes contradictory due to complications arising from photolability, causing compound I signals to appear similar to those of compound II or other forms. However, studies of synthetic systems indicated that protein based compound I intermediates of the oxoiron(IV) porphyrin pi-cation radical type should exhibit vibrational signatures that are different from the non-radical forms.
View Article and Find Full Text PDFThe lipid-modifying effects of statin therapy in hypercholesterolemic African-Americans have not been well characterized. This study compared the efficacy and safety of rosuvastatin and atorvastatin treatment for 6 weeks in hypercholesterolemic African-American adults. In the African American Rosuvastatin Investigation of Efficacy and Safety (ARIES) trial (4522US/0002), 774 adult African-Americans with low-density lipoprotein cholesterol > or = 160 and < or = 300 mg/dl and triglycerides < 400 mg/dl were randomized to receive open-label rosuvastatin 10 or 20 mg or atorvastatin 10 or 20 mg for 6 weeks.
View Article and Find Full Text PDFRapid Commun Mass Spectrom
February 2006
A sensitive method using high-performance liquid chromatography coupled to a mass spectrometer with electrospray ionization source (HPLC/ESI-MS) was developed for detection of ecdysteroids in biological samples. We report here for the first time that ecdysteroids can be classified into three groups based on ESI full-scan mass spectra: group 1 (ecdysone (E), 2-deoxyecdysone (2dE), 2,22-dideoxyecdysone (3beta5beta-KT), and 3alpha5alpha[H]-dihydroxycholest-7-en-6-one (3alpha5alpha-KD)), in which loss of one molecule of water from the protonated molecular ion ([M+H](+)) represents the dominant ion; group 2 (20-hydroxyecdysone (20E), makisterone A (MakA), 3beta5beta-KD, and 3beta5alpha-KD), in which [M+H](+) is a major ion but some water loss is observed; and group 3 (muristerone A (MurA) and ponasterone A (PonA)), in which [M+H](+) is the dominant ion with no water loss observed. Based on the analytical procedure in combination with structural information from the group classification and with the application of source-induced dissociation, we identified free ecdysteroids in biological samples: 20,26-dihydroxyecdysone and ecdysonic acid in the larval hemolymph, and the progressive metabolism of 26-hydroxyecdysone (26E) to 3alpha-26E from day-1 to day-3 embryos of the tobacco hornworm Manduca sexta.
View Article and Find Full Text PDFRats were trained on a delayed matching-to-sample for a spatial location task to examine spatial pattern completion. On the sample phase of the task, rats were trained to move a small black block covering a food well that could appear in one of five possible spatial locations. During the choice phase of the task, rats were required to find the same food well, with the block removed so as to receive reinforcement.
View Article and Find Full Text PDFBackground: Although several studies have investigated patient satisfaction and changes in body image following aesthetic plastic surgery, few have investigated more specific dimensions of body image, including dysphoric emotions that occur in specific social situations or body image quality of life. In addition, few studies have investigated changes in body image that may occur in concert with changes in more general areas of psychosocial functioning, such as depressive symptoms and self-esteem.
Objective: This prospective, multi-site study investigated postoperative satisfaction and changes in psychosocial status following cosmetic surgery.
The cervical spine is injured in 2-3% of major trauma patients. Over the past 15 years there have been dramatic changes in the approach to imaging acute cervical spine trauma. Radiographic clearance for injury must be provided efficiently and accurately.
View Article and Find Full Text PDF1,1-Dichloropropene (1,1-DCPe) is a contaminant of some source waters used to make drinking water. Because of this and the fact that no toxicological data were available for this compound, which is structurally similar to the rodent carcinogen 1,3-dichloropropene (1,3-DCPe), 1,1-DCPe was placed on the Contaminant Candidate List of the US Environmental Protection Agency. Consequently, we have performed a hazard characterization of 1,1-DCPe by evaluating its mutagenicity in the Salmonella assay and its DNA damaging (comet assay) and apoptotic (caspase assay) activities in human lymphoblastoid cells.
View Article and Find Full Text PDFAssessment of fracture healing is a common problem in orthopaedic practice and research. To determine the effectiveness of certain treatments, drugs, mechanical loads, or rehabilitation regimes, the strength of the fracture callus must be determined. Both clinically and experimentally, there is a need to noninvasively and quantitatively evaluate fracture callus quality during healing.
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