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111.
Karen McLuskey Aleksander W. Roszak Yanshi Zhu Neil W. Isaacs 《European biophysics journal : EBJ》2010,39(5):723-755
Integral membrane proteins are involved in a wide range of essential biological functions and the determination of their three-dimensional
structures plays a central role in understanding their function. This review focuses on the structures of one class of integral
membrane proteins: the functionally diverse all-alpha type membrane proteins. It gives an overview of all the structures determined
by X-ray crystallography, describing each system and structure in turn. It shows that the structures of all-alpha type membrane
proteins have made valuable contributions to understanding structure–function relationships in membrane proteins. These range
from the first insights into the function of exciting individual proteins to an in-depth knowledge of protein function from
entire biological systems. 相似文献
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OBJECTIVES--To ascertain the prevalence and duration of use of hormone replacement therapy by menopausal women doctors. DESIGN--Postal questionnaire. SETTING--General practices in the United Kingdom. SUBJECTS--Randomised stratified sample of women doctors who obtained full registration between 1952 and 1976, taken from the current principal list of the Medical Register. MAIN OUTCOME MEASURES--Prevalence and duration of use of hormone replacement therapy; menopausal status. RESULTS--Overall, 45.7% (436/954) of women doctors aged between 45 and 65 years had ever used hormone replacement therapy. When the results from women still menstruating regularly were excluded, 55.2% (428) were ever users and 41.2% (319) current users. The cumulative probability of remaining on hormone replacement therapy was 0.707 at five years and 0.576 at 10 years. CONCLUSIONS--Women doctors have a higher prevalence of use of hormone replacement therapy than has been reported for other women in the United Kingdom, and most users seem to be taking hormone replacement therapy for more than five years. The results may become generalisable to the wider population as information on the potential benefits of hormone replacement therapy is disseminated. 相似文献
113.
B Isaacs 《BMJ (Clinical research ed.)》1978,2(6152):1640-1641
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Kenneth Cusi Scott Isaacs Diana Barb Rita Basu Sonia Caprio W. Timothy Garvey Sangeeta Kashyap Jeffrey I. Mechanick Marialena Mouzaki Karl Nadolsky Mary E. Rinella Miriam B. Vos Zobair Younossi 《Endocrine practice》2022,28(5):528-562
ObjectiveTo provide evidence-based recommendations regarding the diagnosis and management of nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) to endocrinologists, primary care clinicians, health care professionals, and other stakeholders.MethodsThe American Association of Clinical Endocrinology conducted literature searches for relevant articles published from January 1, 2010, to November 15, 2021. A task force of medical experts developed evidence-based guideline recommendations based on a review of clinical evidence, expertise, and informal consensus, according to established American Association of Clinical Endocrinology protocol for guideline development.Recommendation SummaryThis guideline includes 34 evidence-based clinical practice recommendations for the diagnosis and management of persons with NAFLD and/or NASH and contains 385 citations that inform the evidence base.ConclusionNAFLD is a major public health problem that will only worsen in the future, as it is closely linked to the epidemics of obesity and type 2 diabetes mellitus. Given this link, endocrinologists and primary care physicians are in an ideal position to identify persons at risk on to prevent the development of cirrhosis and comorbidities. While no U.S. Food and Drug Administration-approved medications to treat NAFLD are currently available, management can include lifestyle changes that promote an energy deficit leading to weight loss; consideration of weight loss medications, particularly glucagon-like peptide-1 receptor agonists; and bariatric surgery, for persons who have obesity, as well as some diabetes medications, such as pioglitazone and glucagon-like peptide-1 receptor agonists, for those with type 2 diabetes mellitus and NASH. Management should also promote cardiometabolic health and reduce the increased cardiovascular risk associated with this complex disease. 相似文献
117.
Isaacs R Mason KS Teixeira LA Loeb G Hesler S Weigle T Muza A Timer J Saunders M 《Journal of economic entomology》2012,105(3):936-942
Over two growing seasons, Isomate GBM-Plus tube-type dispensers releasing the major pheromone component of grape berry moth, Paralobesia viteana (Clemens) (Lepidoptera: Tortricidae), were evaluated in vineyards (Vitis spp.) in Michigan, New York, and Pennsylvania. Dispensers were deployed in three different density-arrangement treatments: 124 dispensers per ha, 494 dispensers per ha, and a combined treatment with 124 dispensers per ha in the vineyard interior and 988 dispensers per ha at the vineyard border, equivalent to an overall density of 494 dispensers per ha. Moth captures and cluster infestation levels were compared at the perimeter and interior of vineyards receiving these different pheromone treatments and in vineyards receiving no pheromone. Orientation of male moths to pheromone-baited traps positioned at the perimeter and interior of vineyards was reduced as a result of mating disruption treatments compared with the nontreated control. These findings were consistent over both years of the study. Disruption of male moth captures in traps varied from 93 to 100% in treated vineyards, with the 494 dispensers per ha application rates providing significantly higher level of disruption than the 124 dispensers per ha rate, but only in 2007. Measurements of percentage of cluster infestation indicated much higher infestation at perimeters than in the interior of the vineyards in all three regions, but in both sample positions there was no significant effect of dispenser density on cluster infestation levels in either year. The contrasting results of high disruption of moth orientation to traps in vineyards that also had low levels of crop protection from this pheromone treatment are discussed in the context of strategies to improve mating disruption of this tortricid pest. 相似文献
118.
Chae K Isaacs CG Reeves PH Maloney GS Muday GK Nagpal P Reed JW 《The Plant journal : for cell and molecular biology》2012,71(4):684-697
Auxin regulates plant growth and development in part by activating gene expression. Arabidopsis thaliana SMALL AUXIN UP RNAs (SAURs) are a family of early auxin-responsive genes with unknown functionality. Here, we show that transgenic plant lines expressing artificial microRNA constructs (aMIR-SAUR-A or -B) that target a SAUR subfamily (SAUR61-SAUR68 and SAUR75) had slightly reduced hypocotyl and stamen filament elongation. In contrast, transgenic plants expressing SAUR63:GFP or SAUR63:GUS fusions had long hypocotyls, petals and stamen filaments, suggesting that these protein fusions caused a gain of function. SAUR63:GFP and SAUR63:GUS seedlings also accumulated a higher level of basipetally transported auxin in the hypocotyl than did wild-type seedlings, and had wavy hypocotyls and twisted inflorescence stems. Mutations in auxin efflux carriers could partially suppress some SAUR63:GUS phenotypes. In contrast, SAUR63:HA plants had wild-type elongation and auxin transport. SAUR63:GFP protein had a longer half-life than SAUR63:HA. Fluorescence imaging and microsomal fractionation studies revealed that SAUR63:GFP was localized mainly in the plasma membrane, whereas SAUR63:HA was present in both soluble and membrane fractions. Low light conditions increased SAUR63:HA protein turnover rate. These results indicate that membrane-associated Arabidopsis SAUR63 promotes auxin-stimulated organ elongation. 相似文献
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Laboratory and semifield bioassays were conducted to determine the life-stage activity of insecticides for controlling cranberry fruitworm, Acrobasis vaccinii Riley (Lepidoptera: Pyralidae), a key lepidopteran pest of highbush blueberry, Vaccinium corymbosum L. The organophosphates azinphosmethyl and phosmet, the pyrethroid esfenvalerate, and the carbamate methomyl were lethal to all life stages. The neonicotinoids thiacloprid and acetamiprid demonstrated strong larvicidal and ovicidal activity but were somewhat weaker adulticides than the conventional broad-spectrum compounds. Bacillus thuringiensis, indoxacarb, and emamectin benzoate were shown to control A. vacinii primarily through their larvicidal activity. Spinosad was toxic to all life stages, including eggs laid on top of residues and those that were treated topically, but larvicidal activity was short lived. The growth regulators pyriproxyfen and novaluron had strong ovicidal activity when eggs were laid on top of residues but had limited larvicidal activity. Tebufenozide was not directly toxic to eggs, but demonstrated larvicidal activity, and ovilarvicidal activity when topically applied to eggs. Azinphosmethyl, phosmet, indoxacarb, thiacloprid, and acetamiprid were all toxic to the egg parasitoid Trichogramma minutum Riley. In contrast pyriproxyfen, emamectin benzoate, methomyl, novaluron, and spinosad did not negatively affect the survival of T. minutum within Acrobasis vacinii eggs. These results help inform the ongoing development of integrated strategies for insect management in blueberry. 相似文献