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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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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
4.
We determined the 240-nueleotide sequences of the E/NS1 gene junction of four dengue-2 viruses by the primer extension dideoxy chain termination method. These viruses were isolated from dengue patients with different clinical severities in Nakhon Phanom, Northeastern Thailand in 1993. The results were compared with the 52 published dengue-2 sequences of the same gene region. Sequence divergence of four new isolates varied from 4.17% to 5.42% compared with dengue-2 prototype New Guinea C strain whereas it varied from 5.42% to 6.67% and from 6.67% to 7.09% when compared with Jamaica 1409 strain and PR159/S1 strain, respectively. All nucleotide substitutions were found at the 3rd position of the codons which were silent mutations. All 56 isolates studied were classified into five genotypic groups by constructing the dendrogram. The results indicated that four new isolates from Northeastern Thailand belong to genotype II of dengue virus serotype 2, and were most closely related to prototype New Guinea C strain. We also observed the variation in nucleotide and amino acid sequences among clusters of isolates (Thailand-1980, Malaysia-1989 and Thailand-1993) which were obtained from the dengue patients with different clinical severities. The significance of these genetic differences have been discussed in terms of the possible correlation between genetic variability and virulence. 相似文献
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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7.
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
8.
The mechanisms by which molecular motors associate with specific cargo is a central problem in cell organization. The kinesin-like protein Smy1 of budding yeast was originally identified by the ability of elevated levels to suppress a conditional myosin-V mutation (myo2-66), but its function with Myo2 remained mysterious. Subsequently, Myo2 was found to provide an essential role in delivery of secretory vesicles for polarized growth and in the transport of mitochondria for segregation. By isolating and characterizing myo2 smy1 conditional mutants, we uncover the molecular function of Smy1 as a factor that enhances the association of Myo2 with its receptor, the Rab Sec4, on secretory vesicles. The tail of Smy1—which binds Myo2—its central dimerization domain, and its kinesin-like head domain are all necessary for this function. Consistent with this model, overexpression of full-length Smy1 enhances the number of Sec4 receptors and Myo2 motors per transporting secretory vesicle. Rab proteins Sec4 and Ypt11, receptors for essential transport of secretory vesicles and mitochondria, respectively, bind the same region on Myo2, yet Smy1 functions selectively in the transport of secretory vesicles. Thus a kinesin-related protein can function intimately with a myosin-V and its receptor in the transport of a specific cargo. 相似文献
9.
Charles M. Peters Andrew Henderson U Myint Maung U Saw Lwin U Tin Maung Ohn U Kyaw Lwin U Tun Shaung 《Economic botany》2007,61(1):3-13
Although Myanmar exports millions of dollars of rattan cane each year, the last systematic treatment of rattans in this country
was done over 100 years ago, and virtually nothing has been written about the collection and trade of this important forest
resource. Here we report the results from a study of rattans in the Hukaung Valley Tiger Reserve in northern Myanmar. A total
of 15 species of rattan were encountered; seven species are new records for Myanmar and two species are new to science. Inventory
transects revealed that the density of commercial rattans in local forests averages 40.5 canes ≽4m long/hectare. Populations
of all species appear to be actively regenerating. The current pattern of rattan exploitation, however, is largely uncontrolled
and will eventually lead to resource depletion unless some form of management is implemented. 相似文献
10.
Libraty DH Myint KS Murray CK Gibbons RV Mammen MP Endy TP Li W Vaughn DW Nisalak A Kalayanarooj S Hospenthal DR Green S Rothman AL Ennis FA 《PLoS neglected tropical diseases》2007,1(3):e111