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381.
To explore the role of mitochondrial activity in the aging process, we have lowered the activity of the electron transport chain and adenosine 5'-triphosphate (ATP) synthase with RNA interference (RNAi) in Caenorhabditis elegans. These perturbations reduced body size and behavioral rates and extended adult life-span. Restoring messenger RNA to near-normal levels during adulthood did not elevate ATP levels and did not correct any of these phenotypes. Conversely, inhibiting respiratory-chain components during adulthood only did not reset behavioral rates and did not affect life-span. Thus, the developing animal appears to contain a regulatory system that monitors mitochondrial activity early in life and, in response, establishes rates of respiration, behavior, and aging that persist during adulthood.  相似文献   
382.
The purpose of this study was to investigate total baseline plasma cortisol and adrenocorticotropic hormone (ACTH) concentrations, and ACTH-stimulated cortisol concentrations in foals from birth to 12 wk of age. Plasma (baseline) cortisol and ACTH concentrations were measured in 13 healthy foals at birth and at 1, 2, 3, 4, 5, 7, 10, 14, 21, 28, 42, 56, and 84 d of age. Each foal received cosyntropin (0.1 μg/kg) intravenously. Plasma cortisol concentrations were measured before (baseline), and 30, and 60 min after cosyntropin administration at birth and at 3, 5, 7, 10, 14, 21, 28, 42, 56, and 84 d of age. Compared with baseline, cortisol concentration increased significantly 30 min after administration of cosyntropin on all days. Cortisol concentration was highest at birth, measured at 30 and 60 min after cosyntropin administration, compared with all other days. With the exception of birth measurements, cortisol concentration was significantly higher on day 84, measured at 30 and 60 min after cosyntropin administration, when compared with all other days. Baseline plasma ACTH was lowest at birth when compared with concentrations on days 2, 3, 4, 5, 7, 10, 14, 42, 56, and 84. Administration of 0.1 μg/kg of cosyntropin, IV, reliably induces cortisol secretion in healthy foals. Differences in the magnitude of response to cosyntropin are observed depending on the age of the foal. These data should serve as a reference for the ACTH stimulation test in foals and should be useful in subsequent studies to evaluate the hypothalamic-pituitary-adrenal axis in healthy and critically ill foals.  相似文献   
383.
ObjectiveTo evaluate the utility of feline NT-proBNP plasma concentration [NT-proBNP] as a screening tool for cats with subclinical hypertrophic cardiomyopathy (HCM).Animals, materials and methodsForty adult Maine Coon or Maine Coon crossbred cats from the feline HCM research colony at the University of California, Davis were studied. All cats had previously been genotyped as heterozygous or negative for the A31P myosin binding protein C (MYBPC) mutation. Echocardiograms were performed to assess the severity of HCM in each cat. Blood samples were collected for evaluation of [NT-proBNP].ResultsIn these cats with severe HCM, [NT-proBNP] was significantly elevated (P < 0.0001) when compared to all other groups of cats and an [NT-proBNP] > 44pmol/L accurately predicted the presence of severe HCM. However, [NT-proBNP] was not increased in cats with moderate or equivocal HCM when compared to normal cats. Cats heterozygous for the MYBPC mutation had a significantly elevated [NT-proBNP] when compared to cats without the A31P mutation (P = 0.028).ConclusionsMeasurement of [NT-proBNP] has a high sensitivity and specificity as a means of detecting severe HCM in cats, but it is not sensitive for the identification of moderate HCM as judged by the evaluation of Maine Coon and Maine Coon cross cats in our colony. Consequently, we conclude that this test cannot be used to screen cats for the presence of mild to moderate HCM.  相似文献   
384.
Lonicera japonica (Caprifoliaceae) has been known as an anti-inflammatory herb in traditional Chinese medicine for thousands of years and is used constantly for upper respiratory tract infections. Luteolin, an active flavonoid compound isolated from Lonicera japonica, has a spectrum of biological activities, especially with antioxidative and anti-inflammatory properties. However, whether luteolin has a direct inhibitory effect on lung fibrosis has not been established. In this study, we examined the effects of luteolin on lung fibrosis both in vivo and in vitro. We found that oral administration of luteolin (10 mg/kg) efficiently suppressed the neutrophil infiltration as well as TNF-α and IL-6 elevation in the bronchoalveolar lavage fluid in bleomycin-instilled C57BL/6J mice. Luteolin also alleviated collagen deposition, TGF-β1 expression, and lung fibrosis upon bleomycin instillation. A similar tendency was observed in both early and delayed luteolin-treated groups. Next, our in vitro studies showed that luteolin inhibited TGF-β1-induced α-SMA, type I collagen, and vimentin expression in primary cultured mouse lung fibroblasts. Moreover, luteolin significantly blocked TGF-β1-mediated epithelial marker (E-cadherin) downregulation and mesenchymal cell markers (fibronectin and vimentin) upregulation, as well as retaining epithelial morphology in human alveolar epithelial-derived A549 cells. Additionally, luteolin could attenuate TGF-β1-induced Smad3 phosphorylation in both lung fibroblasts and A549 cells. These findings suggest that luteolin has a potent antifibrotic activity; this effect was mediated, at least in part, by inhibition of lung inflammation and suppression of myofibroblast differentiation as well as epithelial-to-mesenchymal transition.  相似文献   
385.
Steam distilled essential oil from the aerial parts of Pogostemon cablin was analyzed by gas chromatography-mass spectrometry (GC-MS). Forty one compounds were identified of which alpha-guaiene (20.62%) and alpha-bulnesene (16.18%) were major constituents. Furthermore, fractionation of the essential oil from P. cablin guided by inhibitory activity against PAF-induced platelet aggregation led to the isolation of the sesquiterpene, alpha-bulnesene.  相似文献   
386.
Infectious pancreatic necrosis virus (IPNV) causes an acute, contagious disease in a number of economically important fish species (Pilcher & Fryer 1980). It is a member of the Birnaviridae (Brown 1986). In this study, the present authors first characterized the process of fish cell damage caused by IPNV infection in cultured cells, and found that it induced fragmentation of chromosomal DNA into oligonucleosomes and also caused nuclear fragmentation by secondary necrosis.  相似文献   
387.
Measurements of either heartbeats or heart rate variability provide important information on metabolic changes and stress responses. In this study, we aimed to determine the suitable temperature conditions for maintaining product quality for post‐harvest processing of mud crab (Scylla serrata) through measuring cardiac performance. A bundle of implanted electrodes was used to record the electrocardiogram, from which the heart rate (HR) and heart rate variability (HRV) were derived to evaluate the physiological performances of the crabs under tying at different seawater temperatures. The lowest standard deviation of HR was detected at the seawater temperature of 18°C for the group of ascending temperatures and at 10°C for the group of descending temperatures. Lower HRV was detected at the range from 10 to 14°C. The results suggest that the temperature range of 14–18°C is suitable to reduce variability in heart rate and may decrease physiological stress. These conditions might help maintain the quality of live crabs during post‐harvest processing and transportation.  相似文献   
388.
Four food grade additives-sodium ascorbate, sodium bicarbonate, sodium carbonate-10-hydrate, and ferrous sulfate-7-hydrate-were selected as the basic ingredients to formulate the controlled atmosphere agents which could effectively remove oxygen and release carbon dioxide. The mathematical models giving the relationships between the formulations and the responses (oxygen and carbon dioxide contents) were developed using response surface methodology (RSM). Within 8-24 h, the oxygen and carbon dioxide contents of all tested formulations could reach constant levels, in the ranges of 2-9% and 0-41%, respectively. These formulations were considered to be effective, safe, and easy to prepare and could be applied to wide varieties of food products.  相似文献   
389.
390.
In this study, waterborne polyurethane (WPU) resins consisted of carboxylic acid and side-chained EO (ethylene oxide) functional groups were prepared via a prepolymer ion-hybrid reaction process. After dipping the WPU on fabrics, the dipped fabrics showed promising deodorization properties for both basic and acidic odors and also showed good wash durability because of the presence of those characteristic groups. Basic odors were neutralized via carboxylic acid groups on the WPU, whereas acidic odors were absorbed by the EO groups through hydrogen bonding. Fourier transform infrared spectroscopy (FT-IR) was used to examine the functional groups of carboxylic acid and EO groups, before and after dipping the WPU on the fabrics. The deodorization properties of the dipped fabrics were associated with the content of the functional groups existing on the WPU molecular chain. Scanning electron microscope (SEM) analysis also revealed that the dipped fabrics had a promising wash durability and deodorization properties after 5 times of laundering because WPU particles were still strongly adhered to the fabrics. More side-chain EO groups, more acetic acid molecules were absorbed; while more-COOH groups in polymer chain, more ammonium molecules were absorbed. Table 2 shows that the synthesized WPU’s possess very highly washed durability.  相似文献   
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