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91.
92.
Bayat S Albu G Layachi S Portier F Fathi M Peták F Habre W 《Journal of applied physiology (Bethesda, Md. : 1985)》2011,111(2):458-464
We studied the relation between changes in pulmonary and systemic hemodynamics to those in the airway resistance, respiratory tissue mechanics, and thoracic gas volume (TGV) following acute hemorrhage and blood reinfusion in rats. Forced oscillation technique was used to measure airway resistance (Raw), respiratory tissue damping, and elastance at baseline and after stepwise 1-ml blood withdrawals up to 5 ml total, followed by stepwise reinfusion up to full restoration. Mean systemic (Pam) and pulmonary arterial pressures and suprarenal aortic blood flow were measured at each step. In supplemental animals, plethysmographic TGV, Pam, and respiratory mechanics measurements were performed. Blood volume loss (BVL) led to proportional decreases in Raw (66.5 ± 8.8 vs. 44.8 ± 9.0 cmH(2)O·s·l(-1) with 5 ml, P < 0.001), Pam, and aortic blood flow. In contrast, tissue damping increased significantly (1,070 ± 91 vs. 1,235 ± 105 cmH(2)O/l, P = 0.009 with 5 ml BVL), whereas tissue elastance did not change significantly. TGV significantly increased with acute BVL (3.7 ± 0.2 vs. 4.2 ± 0.2 ml, P = 0.01). Stepwise reinfusions produced opposite changes in the above parameters, with Raw reaching a higher value than baseline (P = 0.001) upon full volume restoration. Both adrenalin (P = 0.015) and noradrenalin levels were elevated (P = 0.010) after 5-ml blood withdrawal. Our data suggest that the decreases in Raw following BVL may be attributed to the following: 1) an increased TGV enhancing airway parenchymal tethering forces; and 2) an increase in circulating catecholamines. The apparent beneficial effect of a reduction in Raw in acute hemorrhagic shock is counteracted by an increase in dead space and the appearance of peripheral mechanical heterogeneities due to de-recruitment of the pulmonary vasculature. 相似文献
93.
Talita?FA?Ribas Luis?RR?Rodrigues Cleusa?Y?Nagamachi Anderson?JB?Gomes Thayse?CM?Benathar Patricia?CM?O’Brien Fengtang?Yang Malcolm?A?Ferguson-Smith Julio?C?PieczarkaEmail author 《BMC genetics》2013,14(1):119
Background
The genus Micronycteris is a diverse group of phyllostomid bats currently comprising 11 species, with diploid number (2n) ranging from 26 to 40 chromosomes. The karyotypic relationships within Micronycteris and between Micronycteris and other phyllostomids remain poorly understood. The karyotype of Micronycteris hirsuta is of particular interest: three different diploid numbers were reported for this species in South and Central Americas with 2n?=?26, 28 and 30 chromosomes. Although current evidence suggests some geographic differentiation among populations of M. hirsuta based on chromosomal, morphological, and nuclear and mitochondrial DNA markers, the recognition of new species or subspecies has been avoided due to the need for additional data, mainly chromosomal data.Results
We describe two new cytotypes for Micronycteris hirsuta (MHI) (2n?=?26 and 25, NF?=?32), whose differences in diploid number are interpreted as the products of Robertsonian rearrangements. C-banding revealed a small amount of constitutive heterochromatin at the centromere and the NOR was located in the interstitial portion of the short arm of a second pair, confirmed by FISH. Telomeric probes hybridized to the centromeric regions and weakly to telomeric regions of most chromosomes. The G-banding analysis and chromosome painting with whole chromosome probes from Carollia brevicauda (CBR) and Phyllostomus hastatus (PHA) enabled the establishment of genome-wide homologies between MHI, CBR and PHA.Conclusions
The karyotypes of Brazilian specimens of Micronycteris hirsuta described here are new to Micronycteris and reinforce that M. hirsuta does not represent a monotypic taxon. Our results corroborate the hypothesis of karyotypic megaevolution within Micronycteris, and strong evidence for this is that the entire chromosome complement of M. hirsuta was shown to be derivative with respect to species compared in this study.94.
The permanently eutrophic Sundays Estuary experiences recurrent harmful algal blooms (HABs) of Heterosigma akashiwo (Raphidophyceae). This study aimed to identify the environmental variables shaping phytoplankton community composition and succession patterns during a typical spring/summer harmful algal bloom (HAB) period. Monitoring of abiotic and phytoplankton variables was undertaken over the period of a month in 2016. Surface water salinity corresponding to mesohaline conditions (9 to 12) was a prerequisite for site selection. During the study, two HABs (>550 µg Chl a l?1) of H. akashiwo occurred, each lasting for approximately a week in duration. Analyses highlighted nutrient depletion (i.e. nitrate and phosphate concentrations) as the key constraint on bloom duration. When the density of H. akashiwo decreased, the community composition became more diverse with species belonging to Bacillariophyceae and Dinophyceae becoming more abundant; albeit to a lesser degree (<180 µg Chl a l?1). Dissolved oxygen shifted from super-saturated conditions (>14 mg l?1) during peak HAB conditions, to instances of bottom water oxygen depletion (2–4 mg l?1) during the decay phase. These findings highlight the potential severity of transforming a catchment from natural to one that is highly regulated by agricultural practices, while also emphasising the need for management intervention. 相似文献
95.
Azuma K Heilbronn LK Albu JB Smith SR Ravussin E Kelley DE;and the Look AHEAD Adipose Research Group 《American journal of physiology. Endocrinology and metabolism》2007,293(1):E435-E442
Insulin resistance (IR) is typically more severe in obese individuals with type 2 diabetes (T2DM) than in similarly obese non-diabetics but whether there are group differences in body composition and whether such differences contribute to the more severe IR of T2DM is uncertain. DEXA and regional CT imaging were conducted to assess adipose tissue (AT) distribution and fat content in liver and muscle in 67 participants with T2DM (F39/M28, age 60 +/- 7 yr, BMI 34 +/- 3 kg/m(2)) and in 35 similarly obese, non-DM volunteers (F20/M15, age 55 +/- 8 yr, BMI 33 +/- 2 kg/m(2)). A biopsy of subcutaneous abdominal AT was done to measure adipocyte size. A glucose clamp was performed at an insulin infusion of 80 mU x min(-1) x m(-2). There was more severe IR in T2DM (6.1 +/- 2.3 vs. 9.9 +/- 3.3 mg x min(-1) x kg FFM(-1); P < 0.01). Group comparisons of body composition parameters was performed after adjusting for the effect of age, gender, race, height and total fat mass (FM). T2DM was associated with less leg FM (-1.2 +/- 0.4 kg, P < 0.01), more trunk FM (+1.1 +/- 0.4 kg, P < 0.05), greater hepatic fat (P < 0.05), and more subfascial adipose tissue around skeletal muscle (P < 0.05). There was a significant group x sex interaction for VAT (P < 0.01), with greater VAT in women with T2DM (P < 0.01). Mean adipocyte size (AS) did not significantly differ across groups, and smaller AS was associated with increased leg FM, whereas larger AS was related to more trunk FM (both P < 0.05). Group differences in IR were less after adjusting for group differences in leg FM, trunk FM, and hepatic fat, but these adjustments only partially accounted for the greater severity of IR in T2DM. In summary, T2DM, compared with similarly obese nondiabetic men and women, is associated with less leg FM and greater trunk FM and hepatic fat. 相似文献
96.
Albu F Georgiţă C David V Medvedovici A 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2007,846(1-2):222-229
A simple and fast method intended for large-scale bioequivalence studies for the determination of glibenclamide in plasma samples is presented. The chromatographic separation was achieved on a monolithic octadecyl chemically modified silicagel column and a mobile phase containing 42% aqueous 0.1% HCOOH solution (v/v) and 58% acetonitrile, at a flow rate of 1 mL/min, in isocratic conditions. Preparation of plasma samples was based on protein precipitation with acetonitrile. Gliquidone was used as internal standard. The target analytes were transferred into an ion trap mass analyzer via an atmospheric pressure chemical ionization interface. The precursor ions with mass 494 a.m.u. for glibenclamide and 528 a.m.u. for gliquidone were isolated, while in the second MS stage product ions 369 a.m.u. and 403 a.m.u., respectively, were monitored. The analytical process was characterized by a low limit of quantitation of 1.5 ng/mL. The mean recovery for glibenclamide was 98.1+/-2.8% over a concentration interval ranging from 1 to 500 ng/mL. Intra-day and inter-day precision calculated over 2-400 ng/mL concentration interval ranged from 15.4% to 3.4%. Inter-sequence accuracy expressed as % bias from theoretical concentration values over the concentration interval of 10-400 ng/mL fall within -13.9% and +14.6%. The method was applied for evaluation of the bioequivalence between two formulations containing 3.5mg glibenclamide per dose. 相似文献
97.
Kai McKeever Bullard Mohammed K. Ali Giuseppina Imperatore Linda S. Geiss Sharon H. Saydah Jeanine B. Albu Catherine C. Cowie Nancy Sohler Ann Albright Edward W. Gregg 《PloS one》2015,10(4)
Background
Screening guidelines are used to help identify prediabetes and diabetes before implementing evidence-based prevention and treatment interventions. We examined screening practices benchmarking against two US guidelines, and the capacity of each guideline to identify dysglycemia.Methods
Using 2007–2012 National Health and Nutrition Examination Surveys, we analyzed nationally-representative, cross-sectional data from 5,813 fasting non-pregnant adults aged ≥20 years without self-reported diabetes. We examined proportions of adults eligible for diagnostic glucose testing and those who self-reported receiving testing in the past three years, as recommended by the American Diabetes Association (ADA) and the US Preventive Services Task Force (USPSTF-2008) guidelines. For each screening guideline, we also assessed sensitivity, specificity, and positive (PPV) and negative predictive values in identifying dysglycemia (defined as fasting plasma glucose ≥100 mg/dl or hemoglobin A1c ≥5.7%).Results
In 2007–2012, 73.0% and 23.7% of US adults without diagnosed diabetes met ADA and USPSTF-2008 criteria for screening, respectively; and 91.5% had at least one major risk factor for diabetes. Of those ADA- or USPSTF-eligible adults, about 51% reported being tested within the past three years. Eligible individuals not tested were more likely to be lower educated, poorer, uninsured, or have no usual place of care compared to tested eligible adults. Among adults with ≥1 major risk factor, 45.7% reported being tested, and dysglycemia yields (i.e., PPV) ranged from 45.8% (high-risk ethnicity) to 72.6% (self-reported prediabetes). ADA criteria and having any risk factor were more sensitive than the USPSTF-2008 guideline (88.8–97.7% vs. 31.0%) but less specific (13.5–39.7% vs. 82.1%) in recommending glucose testing, resulting in lower PPVs (47.7–54.4% vs. 58.4%).Conclusion
Diverging recommendations and variable performance of different guidelines may be impeding national diabetes prevention and treatment efforts. Efforts to align screening recommendations may result in earlier identification of adults at high risk for prediabetes and diabetes. 相似文献98.
JB Farinha DL Dos Santos G Bresciani LF Bard F de Mello ST Stefanello AA Courtes FAA Soares 《Biology of sport / Institute of Sport》2015,32(2):109-114
The aim of this study was to investigate the impact of moderate aerobic training on functional, anthropometric, biochemical, and health-related quality of life (HRQOL) parameters on women with metabolic syndrome (MS). Fifteen untrained women with MS performed moderate aerobic training for 15 weeks, without modifications of dietary behaviours. Functional, anthropometric, biochemical, control diet record and HRQOL parameters were assessed before and after the training. Despite body weight maintenance, the patients presented decreases in waist circumference (P = 0.001), number of MS components (P = 0.014), total cholesterol (P = 0.049), HDL cholesterol (P = 0.004), LDL cholesterol (P = 0.027), myeloperoxidase activity (P = 0.002) and thiobarbituric acid-reactive substances levels (P = 0.006). There were no differences in total energy, carbohydrate, protein and lipid intake pre- and post-training. Furthermore, improvements in the HRQOL subscales of physical functioning (P = 0.03), role-physical (P = 0.039), bodily pain (P = 0.048), general health (P = 0.046) and social functioning scoring (P = 0.011) were reported. Despite the absence of weight loss, aerobic training induced beneficial effects on functional, anthropometric, biochemical and HRQOL parameters in women with MS. 相似文献
99.
Hatice Kumru Sergiu Albu Semra Oguz Narda Murillo Giuseppe Lucente Josep Valls-Sole 《Journal of musculoskeletal & neuronal interactions》2021,21(4):533
Objectives:We studied the effect of different vibration frequencies on spinal cord excitability and heat pain perception. We hypothesized that the effects of vibration on spinal cord reflexes, and, also those on heat pain perception, depend on vibration frequency.Methods:In 9 healthy subjects, we applied vibration over the tibialis anterior muscle at three different frequencies (50, 150, or 250 Hz) on spinal cord reflex excitably, tested with the H reflex and the T wave in the soleus muscle, as well as on sensory and pain perception, tested by measuring warm perception (WT) and heat pain perception thresholds, (HPT) in sites rostral and caudal to vibration. Exams were carried out before, during, and after vibration.Results:The amplitude of the H reflex and T wave significantly decreased during vibration in comparison to baseline. Low frequencies (50 and 150Hz) induced greater reflex suppression than high frequency (250Hz). No significant changes were observed on WT and HPT.Conclusions:The effects of vibratory stimulation can be summarized as frequency-related suppression of the spinal cord excitability without an effect on warm and heat pain perception. The present results may help to design vibration-related interventions intended to diminish spinal cord reflex excitability in spastic patients. 相似文献
100.
A phylogenetic survey using the polymerase chain reaction (PCR) has
identified four major P element subfamilies in the saltans and willistoni
species groups of Drosophila. One subfamily, containing about half of the
sequences studied, consists of elements that are very similar to the
canonical (and active) P element from D. melanogaster. Within this
subfamily, nucleotide sequence differentiation among different copies from
the same species and among elements from different species is relatively
low. This observation suggests that the canonical elements are relatively
recent additions to the genome or, less likely, are evolving slowly
relative to the other subfamilies. Elements belonging to the three
noncanonical lineages are distinct from the canonical elements and from one
another. Furthermore, there is considerably more sequence variation, on the
average, within the noncanonical subfamilies compared to the canonical
elements. Horizontal transfer and the coexistence of multiple,
independently evolving element subfamilies in the same genome may explain
the distribution of P elements in the saltans and willistoni species
groups. Such explanations are not mutually exclusive, and each may be
involved to varying degrees in the maintenance of P elements in natural
populations of Drosophila.
相似文献