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1.
In six hypothyroid patients (2 male, 4 females, ages 22 through 59 years), plasma renin activity (PRA) and aldosterone (Aldo) were measured when the patients were euthyroid on levothyroxine therapy and one month after the therapy was stopped. Colonic mucosal potential differences were measured during the hypothyroid and euthyroid stages, and catecholamine sensitivity was determined by the blood pressure response to infused norepinephrine. Significant differences were observed in the PRA and aldosterone concentrations which were 4.1 +/- 2.5 ng/ml/h and 9.4 +/- 5.9 ng/dl, respectively in the hypothyroid stage and 6.9 +/- 2.3 ng/ml/h and 15.2 +/- 7.3 ng/dl, respectively when the patients were made euthyroid. The colonic mucosal potential differences (which reflect increased endogenous mineralocorticoid activity), became more electronegative after correction of hypothyroidism (-16.8 +/- 7.5 mV vs -32 +/- 18.2 mV; P less than 0.04) concentrations. Statistically significant decreases in norepinephrine pressor effects were observed in hypothyroid patients when compared to the euthyroid state (7.4 +/- 2.3 vs 10.9 +/- 1.9 micrograms/ng/min; P less than 0.01). It is concluded that patients with hypothyroidism have a hormonal pattern reminiscent of "low renin hypertension", and exhibit decreased sensitivity to catecholamines. Such changes are corrected when the patients become euthyroid on levothyroxine therapy. 相似文献
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J B Gabrion H Barrière B Nguyen Than Dao M Chambard J Mauchamp F Regnouf L A Pradel 《European journal of cell biology》1990,52(2):282-290
A fodrin-like protein purified from porcine thyroid cells and characterized by its properties identical to those of pig brain spectrin (F. Regnouf et al., Eur. J. Biochem. 153, 313-319 (1985)) has been localized by immunofluorescence and electron immunocytochemistry in porcine and rat thyroid. Fodrin-like polypeptides were detected in subplasmalemmal meshworks of microfilaments attached to isolated or in situ plasma membranes. In resting cells, fodrin was found under apical and basolateral membrane domains, whereas it was always absent under the pseudopod membrane domain induced by acute TSH stimulation in vitro, using monolayers of porcine cultured cells attached to collagen permeable substrates, as well as in vivo, using rats intravenously treated with TSH. Thyroid fodrin could be involved in exocytosis and membrane stabilization which occurs during the formation of pseudopods induced by TSH stimulation. 相似文献
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Nanda Kyaw Thu Yuuhiko Tanabe Hiroshi Matsuura Makoto M. Watanabe 《Phycological Research》2020,68(3):216-226
Oscillatoria kawamurae is an unusual freshwater cyanobacterium because of its large trichome and ambiguous gas vacuole. Because little is known about its phenotypic or genotypic characteristics, this study conducted morphological, biochemical, and genetic characterization of O. kawamurae strains isolated from Japan, Laos, and Myanmar. All strains displayed similar morphological characteristics; however some differences were observed in vegetative cell widths, trichome colors, and the distribution patterns of their gas vacuole‐like structures. The in vivo and phycobiliprotein absorption spectra revealed the two different trichome colors found in the four representative strains of O. kawamurae (Inle1, Lao7, Biwa6, and Inba3). These different trichome colors corresponded to the different ratios of phycoerythrin and phycocyanin, the two types of phycobilin pigments: 0.25 for olive‐green strain (Inle1) and 0.65–0.73 for brown‐green strains (Biwa6, Inba3, and Lao7). Cellular fatty acid compositions of the four strains were C14:0, C15:0, C16:0, C16:1c, C17:0, C18:0, C18:1c, C18:3α and C18:4, whereas two strains (Biwa6 and Inba3) lacked C17:0. Of the fatty acids, palmitic acid (C16:0) was predominant. PCR experiments using primers targeting a gas vesicle gene (gvpA) recovered gvpA fragments from all O. kawamurae strains, suggesting that this species has true gas vacuoles. The 16S rDNA sequences of all of the strains were identical regardless of their different trichome colors and/or geographic origins. Phylogenetic analyses based on the 16S rDNA sequences indicated that O. kawamurae forms a monophyletic clade with O. princeps CCALA 1115 clB1 and O. duplisecta ETS‐06. We discuss the taxonomy of O. kawamurae based on the data obtained in this study. 相似文献
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Kamal Laina Zarisa Mohd Adam Mowaffaq Adam Ahmed Shahpudin Siti Nurfatimah Mohd. Shuib Ahmad Naqeeb Sandai Rosline Hassan Norazian Mohd Tabana Yasser Basri Dayang Fredalina Than Leslie Thian Lung Sandai Doblin 《Mycopathologia》2021,186(2):221-236
Mycopathologia - Candida albicans has been reported globally as the most widespread pathogenic species contributing candidiasis from superficial to systemic infections in immunocompromised... 相似文献
8.
A Systematic Review of Risk Factors Associated with Surgical Site Infections among Surgical Patients
Ellen Korol Karissa Johnston Nathalie Waser Frangiscos Sifakis Hasan S. Jafri Mathew Lo Moe H. Kyaw 《PloS one》2013,8(12)
Importance
Surgical site infection (SSI) complicates 2-5% of surgeries in the United States. Severity of SSI ranges from superficial skin infection to life-threatening conditions such as severe sepsis, and SSIs are responsible for increased morbidity, mortality, and economic burden associated with surgery. Staphylococcus aureus (S. aureus) is a commonly-isolated organism for SSI, and methicillin-resistant S. aureus SSI incidence is increasing globally.Objective
The objective of this systematic review was to characterize risk factors for SSI within observational studies describing incidence of SSI in a real-world setting.Evidence Review
An initial search identified 328 titles published in 2002-2012; 57 were identified as relevant for data extraction. Extracted information included study design and methodology, reported cumulative incidence and post-surgical time until onset of SSI, and odds ratios and associated variability for all factors considered in univariate and/or multivariable analyses.Findings
Median SSI incidence was 3.7%, ranging from 0.1% to 50.4%. Incidence of overall SSI and S. aureus SSI were both highest in tumor-related and transplant surgeries. Median time until SSI onset was 17.0 days, with longer time-to-onset for orthopedic and transplant surgeries. Risk factors consistently identified as associated with SSI included co-morbidities, advanced age, risk indices, patient frailty, and surgery complexity. Thirteen studies considered diabetes as a risk factor in multivariable analysis; 85% found a significant association with SSI, with odds ratios ranging from 1.5-24.3. Longer surgeries were associated with increased SSI risk, with a median odds ratio of 2.3 across 11 studies reporting significant results.Conclusions and Relevance
In a broad review of published literature, risk factors for SSI were characterized as describing reduced fitness, patient frailty, surgery duration, and complexity. Recognition of risk factors frequently associated with SSI allows for identification of such patients with the greatest need for optimal preventive measures to be identified and pre-treatment prior to surgery. 相似文献9.
E. Catão A. P. Castro C. C. Barreto R. H. Krüger C. M. Kyaw 《Archives of microbiology》2013,195(7):507-512
Although the richness of Bacteria and Fungi in Cerrado’ soils has been reported, here we report, for the first time, the archaeal community in Cerrado’s soils. DNA extracted from soil of two distinct vegetation types, a dense subtype of sensu strict (cerrado denso) and riverbank forest (mata de galeria), was used to amplify Archaea-specific 16S rRNA gene. All of the fragments sequenced were classified as Archaea into the phylum Thaumarchaeota, predominantly affiliated to groups I.1b and I.1c. Sequences affiliated to the group I.1a were found only in the soil from riverbank forest. Soils from ‘cerrado denso’ had greater Archaea richness than those from ‘mata de galeria’ based on the richness indexes and on the rarefaction curve. β-Diversity analysis showed significant differences between the sequences from the two soil areas studied because of their different thaumarchaeal group composition. These results provide information about the third domain of life from Cerrado soils. 相似文献
10.
Aung Than Melvin Khee-Shing Leow Peng Chen 《The Journal of biological chemistry》2013,288(22):15520-15531
Angiotensin II (AngII), a peptide hormone released by adipocytes, can be catabolized by adipose angiotensin-converting enzyme 2 (ACE2) to form Ang(1–7). Co-expression of AngII receptors (AT1 and AT2) and Ang(1–7) receptors (Mas) in adipocytes implies the autocrine regulation of the local angiotensin system upon adipocyte functions, through yet unknown interactive mechanisms. In the present study, we reveal the adipogenic effects of Ang(1–7) through activation of Mas receptor and its subtle interplays with the antiadipogenic AngII-AT1 signaling pathways. Specifically, in human and 3T3-L1 preadipocytes, Ang(1–7)-Mas signaling promotes adipogenesis via activation of PI3K/Akt and inhibition of MAPK kinase/ERK pathways, and Ang(1–7)-Mas antagonizes the antiadipogenic effect of AngII-AT1 by inhibiting the AngII-AT1-triggered MAPK kinase/ERK pathway. The autocrine regulation of the AngII/AT1-ACE2-Ang(1–7)/Mas axis upon adipogenesis has also been revealed. This study suggests the importance of the local regulation of the delicately balanced angiotensin system upon adipogenesis and its potential as a novel therapeutic target for obesity and related metabolic disorders. 相似文献