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51.
The metabolism of hepcidin is profoundly modified in chronic kidney disease (CKD). We investigated its relation to iron disorders, inflammation and hemoglobin (Hb) level in 199 non-dialyzed, non-transplanted patients with CKD stages 1–5. All had their glomerular filtration rate measured by 51Cr-EDTA renal clearance (mGFR), as well as measurements of iron markers including hepcidin and of erythropoietin (EPO). Hepcidin varied from 0.2 to 193 ng/mL. The median increased from 23.3 ng/mL [8.8–28.7] to 36.1 ng/mL [14.1–92.3] when mGFR decreased from ≥60 to <15 mL/min/1.73 m2 (p = 0.02). Patients with absolute iron deficiency (transferrin saturation (TSAT) <20% and ferritin <40 ng/mL) had the lowest hepcidin levels (5.0 ng/mL [0.7–11.7]), and those with a normal iron profile (TSAT ≥20% and ferritin ≥40), the highest (34.5 ng/mL [23.7–51.6]). In multivariate analysis, absolute iron deficiency was associated with lower hepcidin values, and inflammation combined with a normal or functional iron profile with higher values, independent of other determinants of hepcidin concentration, including EPO, mGFR, and albuminemia. The hepcidin level, although it rose overall when mGFR declined, collapsed in patients with absolute iron deficiency. There was a significant interaction with iron status in the association between Hb and hepcidin. Except in absolute iron deficiency, hepcidin’s negative association with Hb level indicates that it is not down-regulated in CKD anemia.  相似文献   
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<正>焦瑞身(Jui-shen Chiao)1918-09-13,2009年12月22日卒于上海。1936年考取清华大学化学系,1941年毕业于西南联合大学并留校任化学系助教。1946年在北京大学农学院农化系任助教。  相似文献   
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BackgroundIn Phase II/III randomized controlled clinical trials for the treatment of acute uncomplicated malaria, pyronaridine–artesunate demonstrated high efficacy and a safety profile consistent with that of comparators, except that asymptomatic, mainly mild-to-moderate transient increases in liver aminotransferases were reported for some patients. Hepatic safety, tolerability, and effectiveness have not been previously assessed under real-world conditions in Africa.Methods and findingsThis single-arm, open-label, cohort event monitoring study was conducted at 6 health centers in Cameroon, Democratic Republic of Congo, Gabon, Ivory Coast, and Republic of Congo between June 2017 and April 2019. The trial protocol as closely as possible resembled real-world clinical practice for the treatment of malaria at the centers. Eligible patients were adults or children of either sex, weighing at least 5 kg, with acute uncomplicated malaria who did not have contraindications for pyronaridine–artesunate treatment as per the summary of product characteristics. Patients received fixed-dose pyronaridine–artesunate once daily for 3 days, dosed by body weight, without regard to food intake. A tablet formulation was used in adults and adolescents and a pediatric granule formulation in children and infants under 20 kg body weight. The primary outcome was the hepatic event incidence, defined as the appearance of the clinical signs and symptoms of hepatotoxicity confirmed by a >2× rise in alanine aminotransferase/aspartate aminotransferase (ALT/AST) versus baseline in patients with baseline ALT/AST >2× the upper limit of normal (ULN). As a secondary outcome, this was assessed in patients with ALT/AST >2× ULN prior to treatment versus a matched cohort of patients with normal baseline ALT/AST. The safety population comprised 7,154 patients, of mean age 13.9 years (standard deviation (SD) 14.6), around half of whom were male (3,569 [49.9%]). Patients experienced 8,560 malaria episodes; 158 occurred in patients with baseline ALT/AST elevations >2×ULN. No protocol-defined hepatic events occurred following pyronaridine–artesunate treatment of malaria patients with or without baseline hepatic dysfunction. Thus, no cohort comparison could be undertaken. Also, as postbaseline clinical chemistry was only performed where clinically indicated, postbaseline ALT/AST levels were not systematically assessed for all patients. Adverse events of any cause occurred in 20.8% (1,490/7,154) of patients, most frequently pyrexia (5.1% [366/7,154]) and vomiting (4.2% [303/7,154]). Adjusting for Plasmodium falciparum reinfection, clinical effectiveness at day 28 was 98.6% ([7,369/7,746] 95% confidence interval (CI) 98.3 to 98.9) in the per-protocol population. There was no indication that comorbidities or malnutrition adversely affected outcomes. The key study limitation was that postbaseline clinical biochemistry was only evaluated when clinically indicated.ConclusionsPyronaridine–artesunate had good tolerability and effectiveness in a representative African population under conditions similar to everyday clinical practice. These findings support pyronaridine–artesunate as an operationally useful addition to the management of acute uncomplicated malaria.Trial registrationClinicalTrials.gov NCT03201770.

Gaston Tona Lutete and co-workers report on safety and effectiveness of the antimalarial drug pyronaridine-artesunate in African countries.  相似文献   
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Missing outcome data due to loss to follow-up occurs frequently in clinical cohort studies of HIV-infected patients. Censoring patients when they become lost can produce inaccurate results if the risk of the outcome among the censored patients differs from the risk of the outcome among patients remaining under observation. We examine whether patients who are considered lost to follow up are at increased risk of mortality compared to those who remain under observation. Patients from the US Centers for AIDS Research Network of Integrated Clinical Systems (CNICS) who newly initiated combination antiretroviral therapy between January 1, 1998 and December 31, 2009 and survived for at least one year were included in the study. Mortality information was available for all participants regardless of continued observation in the CNICS. We compare mortality between patients retained in the cohort and those lost-to-clinic, as commonly defined by a 12-month gap in care. Patients who were considered lost-to-clinic had modestly elevated mortality compared to patients who remained under observation after 5 years (risk ratio (RR): 1.2; 95% CI: 0.9, 1.5). Results were similar after redefining loss-to-clinic as 6 months (RR: 1.0; 95% CI: 0.8, 1.3) or 18 months (RR: 1.2; 95% CI: 0.8, 1.6) without a documented clinic visit. The small increase in mortality associated with becoming lost to clinic suggests that these patients were not lost to care, rather they likely transitioned to care at a facility outside the study. The modestly higher mortality among patients who were lost-to-clinic implies that when we necessarily censor these patients in studies of time-varying exposures, we are likely to incur at most a modest selection bias.  相似文献   
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柬埔寨是东南亚生物自然资源最为完整和最多样化的国家之一。拥有数量和种类惊人的栖息地和特有物种,包括灵长类、亚洲象、熊、水獭、鳄鱼、穿山甲、大型淡水鱼和龟鳖等。  相似文献   
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为便于本地社区了解当地生态系统的复杂性,以便在得益于自然环境的同时更好地珍视、利用和保护,国际山地综合发展中心(ICIMOD)联合其他环保组织提出了“神山圣湖山水自然保护倡议”(KSLCI),制作了圣地区域的手绘宣传图册,其目的在于,协助山地乡村社区更好地了解本地所面临的变化和机遇。手册以生活于冈仁波齐(Kailash)圣地的本地社区为服务对象,也可为范围更大的山地社区提供助益。  相似文献   
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