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Jamie H Macdonald Mysore K Phanish Samuele M Marcora Mahdi Jibani Lionel L O Bloodworth Jeffrey M P Holly Andrew B Lemmey 《Journal of renal nutrition》2004,14(4):248-252
BACKGROUND: Hemodialysis (HD) patients typically have reduced muscle mass and diminished functional capacity. The role of the muscle insulin-like growth factors (IGFs), a principal anabolic system that is involved in protein synthesis and that has downregulation that is implicated in muscle loss in animal models of uremia, has previously not been assessed in vivo in HD patients. METHODS: Seventeen HD patients were compared cross-sectionally with 17 age-, sex-, and body mass index-matched healthy controls. Body composition was assessed by dual energy x-ray absorptiometry and bioelectrical impedance spectrometry; functional capacity by hand grip strength, quadriceps strength, and 30-second sit-to-stand test; systemic inflammation by tumor necrosis factor-alpha (TNF-alpha) and TNF receptor 1 (TNFR1); serum and muscle IGF-I and IGFBP-3 by radioimmunoassay; and fragmentation of serum IGFBP-3 by Western immunoblotting. RESULTS: Appendicular lean mass was significantly decreased in HD patients compared with controls (17.6 +/- 0.9 versus 21.5 +/- 1.5 kg, P < .05), as were all measures of functional capacity (P < .01 to .001), and highly significant positive correlations between appendicular lean mass and functional capacity were evident (appendicular lean mass and hand-grip strength, quadriceps strength, 30-second sit-to-stand test, all P < .001). TNF-alpha and TNFR1 were elevated in patients (P < .001). Although serum IGF-I and IGFBP-3 levels did not differ between the groups (P = .295 and .379 respectively), fragmented IGFBP-3 levels were increased (53.1 +/- 16.0 versus 29.81 +/- 15.3%, P < .005). In contrast, muscle IGF-I was substantially diminished in the patient group (n = 7) relative to control (n = 5) levels (0.84 +/- 0.06 versus 2.78 +/- 1.80 pg/microg, P < .05). CONCLUSIONS: We provide evidence of reduced IGF-I in HD patients' skeletal muscle that may be a causal factor in the muscle wasting characteristic of this population. Future research should determine the exact consequences and causes of alterations to the muscle IGF system in HD patients. 相似文献
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Helicobacter hepaticus hydrogenase mutants are deficient in hydrogen-supported amino acid uptake and in causing liver lesions in A/J mice 总被引:1,自引:0,他引:1 下载免费PDF全文
Helicobacter hepaticus, a causative agent of chronic hepatitis and hepatocellular carcinoma in mice, expresses a nickel-containing hydrogen-oxidizing hydrogenase enzyme. Growth of a hyaB gene-targeted mutant was unaffected by the presence of hydrogen, unlike the wild-type strain, which showed an enhanced growth rate when supplied with H(2). Hydrogenase activities in H. hepaticus were constitutive and not dependent on the inclusion of H(2) during growth. Addition of nickel during growth significantly stimulated both urease (for wild-type and hyaB) and hydrogenase (for wild-type) activities. In a 5-h period, the extent of (14)C-labeled amino acid uptake by the wild type was markedly enhanced in the presence of hydrogen and was >5-fold greater than that of the hyaB mutant strain. In the presence of H(2), the short-term whole-cell amino acid uptake V(max) of the parent strain was about 2.2-fold greater than for the mutant, but the half-saturation affinity for amino acid transport was the same for the parent and mutant strain. The liver- and cecum-colonizing abilities of the strains was estimated by real-time PCR quantitation of the H. hepaticus-specific cytolethal distending toxin gene and showed similar animal colonization for the hyaB mutant and the wild type. However, at 21 weeks postinoculation, the livers from mice inoculated with wild type exhibited moderate lobular lymphoplasmacytic hepatitis with hepatocytic coagulative necrosis, but the hydrogenase mutants exhibited no histological evidence of lobular inflammation or necrosis. 相似文献
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Maneet Singh Hennaav Kaur Dhillon Parul Ichhpujani Sudarshan Iyengar Rishemjit Kaur 《Indian journal of ophthalmology》2022,70(5):1773
Purpose:COVID-19-associated mucormycosis (CAM) was a serious public health problem during the second wave of COVID-19 in India. We planned to analyze public perceptions by sentiment analysis of Twitter data regarding CAM.Methods:In this observational study, the application programming interface (API) provided by the Twitter platform was used for extracting real-time conversations by using keywords related to mucormycosis (colloquially known as “black fungus”), from May 3 to August 29, 2021. Lexicon-based sentiment analysis of the tweets was done using the Vader sentiment analysis tool. To identify the overall sentiment of a user on any given topic, an algorithm to label a user “k” based on their sentiments was used.Results:A total of 4,01,037 tweets were collected between May 3 and August 29, 2021, and the peak frequency of 1,60,000 tweets was observed from May 17 to May 23, 2021. Positive sentiment tweets constituted a larger share as compared to negative sentiment tweets, with weekly variations. A temporal analysis of the demand for utilities showed that the demand was high in the initial period but decreased with time, which was associated with the availability of resources.Conclusion:Sentiment analysis using Twitter data revealed that social media platforms are gaining popularity to express one’s emotions during the ongoing COVID-19 pandemic. In our study, time-based assessment of tweets showed a reduction over time in the frequency of negative sentiment tweets. The polarization in the retweet network of users, based on sentiment polarity, showed that the users were well connected, highlighting the fact that such issues bond our society rather than segregating it. 相似文献
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Sudarshan Kumar Vijay M.D. D.M. Bhuwan Chandra Tiwari M.D. D.M. Mukul Misra M.D. D.M. Sudhanshu Kumar Dwivedi M.D. D.M. 《Echocardiography (Mount Kisco, N.Y.)》2014,31(1):E24-E26
The mitral valve aneurysm is a rare complication of infective endocarditis involving mitral or aortic valve. The perforation of the mitral valve aneurysm can lead to significant mitral regurgitation (MR) or thromboembolism, which can cause sudden hemodynamic deterioration. We describe here a case of healed infective endocarditis of the aortic valve with ruptured mitral valve aneurysm that led to severe MR. The aneurysm of the anterior mitral leaflet was diagnosed by two‐dimensional transthoracic echocardiography. In this case, three‐dimensional transthoracic echocardiography demonstrated the detailed morphology of mitral valve aneurysm which resulted in successful surgical repair of the aneurysm. 相似文献
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