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BACKGROUND AND AIM: Studies on Molecular Adsorbent Recycling Systems (MARS) showed inconclusive survival benefits. PATIENTS AND METHOD: We evaluated the efficacy of MARS for patients with either acute liver failure (ALF) or acute-on-chronic liver failure (AoCLF) at our centre, from February 2002 till April 2006 retrospectively. RESULTS: Fifty ALF patients underwent median (range) three (1-10) sessions of MARS. Acute exacerbations of chronic hepatitis B (n=26) and drug-induced liver injury (n=12) were the commonest causes. Living donors were available in 6, 2 paediatric patients underwent left lobe and four adults underwent right lobe living donor liver transplant. Among the 44 ALF patients without a suitable living donor, one underwent deceased donor liver transplant and survived, another 19-year-old male with acute exacerbations of chronic hepatitis B recovered without transplant, and the rest died. Twenty-six had AoCLF and underwent four (1-10) MARS sessions. Sepsis (n=16) and upper gastrointestinal bleeding (n=4) were the commonest precipitating factors. None had a suitable living or deceased donor, suitable for transplantation during their hospitalization. Only one of 26 AoCLF patients survived the hospitalization, but the survivor died of sepsis 1 month later. CONCLUSION: In this non-randomized study, survival after MARS was related to the availability of transplant, and in patients where living or deceased donor transplant was unavailable, MARS was of little benefit. Randomized-controlled trials on MARS((R)) are urgently needed to clarify its clinical utility.  相似文献   
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Rickettsial infections represent a major cause of non-malarial febrile illnesses among the residents of Southeast Asia and returned travelers from that region. There are several challenges in recognition, diagnosis, and management of rickettsioses endemic to Southeast Asia. This review focuses on the prevalent rickettsial infections, namely, murine typhus (Rickettsia typhi), scrub typhus (Orientia tsutsugamushi), and members of spotted fever group rickettsiae. Information on epidemiology and regional variance in the prevalence of rickettsial infections is analyzed. Clinical characteristics of main groups of rickettsioses, unusual presentations, and common pitfalls in diagnosis are further discussed. In particular, relevant epidemiologic and clinical aspects on emerging spotted fever group rickettsiae in the region, such as Rickettsia honei, R. felis, R. japonica, and R. helvetica, are presented. Furthermore, challenges in laboratory diagnosis and management aspects of rickettsial infections unique to Southeast Asia are discussed, and data on emerging resistance to antimicrobial drugs and treatment/prevention options are also reviewed.  相似文献   
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Efficient derivation of neural cells from human embryonic stem cells (hESCs) remains an unmet need for the treatment of neurological disorders. The limiting factors for current methods include being labor-intensive, time-consuming and expensive. In this study, we hypothesize that the substrate topography, with optimal geometry and dimension, can modulate the neural fate of hESCs and enhance the efficiency of differentiation. A multi-architectural chip (MARC) containing fields of topographies varying in geometry and dimension was developed to facilitate high-throughput analysis of topography-induced neural differentiation in vitro. The hESCs were subjected to “direct differentiation”, in which small clumps of undifferentiated hESCs were cultured directly without going through the stage of embryoid body formation, on the MARC with N2 and B27 supplements for 7 days. The gene and protein expression analysis indicated that the anisotropic patterns like gratings promoted neuronal differentiation of hESCs while the isotropic patterns like pillars and wells promoted the glial differentiation of hESCs. This study showed that optimal combination of topography and biochemical cues could shorten the differentiation period and allowed derivation of neurons bearing longer neurites that were aligned along the grating axis. The MARC platform would enable high-throughput screening of topographical substrates that could maximize the efficiency of neuronal differentiation from pluripotent stem cells.  相似文献   
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Background

Kidney disease is the 9th leading cause of death in Singapore. While preventive effects have focused on early detection and education, little is known about the knowledge level of chronic kidney disease (CKD) locally. We seek to evaluate the knowledge of CKD among primary care patients.

Methods

We conducted a cross-sectional survey of a convenience sample of 1520 patients from 3 primary care centers. Those with existing CKD or on dialysis were excluded. Knowledge was assessed based on 7 questions on CKD in the self-administered questionnaire. One point was given for each correct answer with a maximum of 7 points.

Results

1435 completed all 7 questions on CKD. Mean age was 48.9 ±15.0 (SD) years. 50.9% were male. 62.3% had a secondary and below education and 52.4% had a monthly household income of????$2000. 43.7% had chronic diseases. Mean score was 3.44?±?1.53 (out of a maximum of 7). Median score was 4. In multivariate logistic regression, being older {>60?years [Odds Ratio (OR) 0.50, 95% Confidence Interval (CI) 0.32-0.79]; 40?C60?years (OR 0.62, 95% CI 0.43,0.89)}, less educated [up to primary education (OR 0.33, 95% CI 0.22-0.49)], having a lower monthly household income [<S$2000 (OR 0.41, 95% CI 0.26-0.66); S$2000-4999 (OR 0.53, 95%CI, 0.33-0.83)], and being non-professionals [OR 0.66, 95% CI 0.43-0.99] (all p?<?0.05)] were likely to score less.

Conclusion

This suggests that CKD education should be targeted at older patients with lower education and lower socioeconomic status.  相似文献   
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The chemical constituents of 95% EtOH extract of yacon leaves were separated to yield two new sesquiterpene lactones, together with three known compounds. The two new compounds were characterized to be 8β-angeloyloxy-13-methoxyl-11, 13-dihydromelampolid-14-oic acid methyl ester (1) and 8β-(3-methylbut-2-enoyl) oxy-13-methoxyl-11, 13-dihydromelampolid-14-oic acid methyl ester (2) on the basis of NMR spectra, HR-MS and other spectroscopic methods. The cytotoxicity of compounds 1–5 were evaluated on human hepatoma cell Bel-7402 and all the compounds showed moderate cytotoxicity.  相似文献   
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