儿童癌症幸存者成年后的慢性疾病

由于治疗方法的进步,近80%的儿童和青少年癌症患者能够长期生存。在美国,约有270000例儿童癌症的幸存者,即每640名20至39岁成年人中就有一名幸存者。大量的幸存者有利于儿童癌症治疗后长期健康结果的研究。现在可以明确的是,化疗和放疗所致的儿童各器官系统损害在临床上可能潜伏多年。为了全面了解治疗儿童癌症而继发的健康问题,重要的是衡量三项长期结果:健康状况、死亡率和患病率。这三项中,关于前两项已有相当好的研究报道。在一项对20227例癌症5年生存者的回顾性分析中,Mertens等发现以下原因导致的超额死亡率具有统计学意义:继发癌症(…     

Mutations in Emery-Dreifuss muscular dystrophy and their effects on emerin protein expression

Seventeen families with Emery-Dreifuss muscular dystrophy (EDMD) have been studied both by DNA sequencing and by emerin protein expression. Fourteen had mutations in the X-linked emerin gene, while three showed evidence of autosomal inheritance. Twelve of the 14 emerin mutations caused early termination of translation. An in-frame deletion of six amino acids from the C-terminal transmembrane helix caused almost complete absence of emerin from muscle with no localization to the nuclear membrane, although mRNA levels were normal. This shows that mutant emerin proteins are unstable if they are unable to integrate into a membrane. A 22 bp deletion in the promoter region was expected to result in reduced emerin production, but normal amounts of emerin of normal size were found in leucocytes and lymphoblastoid cell lines. This shows that DNA analysis is necessary to exclude emerin mutations in suspected X-linked EDMD. Emerin levels in female carriers often deviated from the expected 50% and this was due, in at least two families, to skewed emerin mRNA expression from the normal and mutated alleles. In one family with a novel deletion of the last three exons of the emerin gene, a carrier had a cardiomyopathy and very low emerin levels (<5% of normal) due to skewed X-inactivation. In the three autosomal cases of EDMD, emerin was normal on western blots of blood cells, which suggests that autosomal EDMD is not caused by indirect reduction of emerin levels.      

Catch-up growth up to ten years of age in children born very preterm or with very low birth weight

Background  

Improved survival due to advances in neonatal care has brought issues such as postnatal growth and development more to the focus of our attention. Most studies report stunting in children born very preterm and/or small for gestational age. In this article we study the growth pattern of these children and aim to identify factors associated with postnatal catch-up growth.     

Prediction modeling of physiological responses and human performance in the heat

Over the last two decades, our laboratory has been establishing the data base and developing a series of predictive equations for deep body temperature, heart rate and sweat loss responses of clothed soldiers performing physical work at various environmental extremes. Individual predictive equations for rectal temperature, heart rate and sweat loss as a function of the physical work intensity, environmental conditions and particular clothing ensemble have been published in the open literature. In addition, important modifying factors such as energy expenditure, state of heat acclimation and solar heat load have been evaluated and appropriate predictive equations developed. Currently, we have developed a comprehensive model which is programmed on a Hewlett-Packard 41 CV hand held calculator. The primary physiological inputs are deep body (rectal) temperature and sweat loss while the predicted outputs are the expected physical work--rest cycle, the maximum single physical work time if appropriate, and the associated water requirements. This paper presents the mathematical basis employed in the development of the various individual predictive equations of our heat stress model. In addition, our current heat stress prediction model as programmed on the HP 41 CV is discussed from the standpoint of propriety in meeting the Army's needs and therefore assisting in military mission accomplishment.     

日本血吸虫SjCa8基因的原核表达及其免疫学特征分析

目的表达和纯化日本血吸虫钙结合蛋白(SjCa8),研究其免疫学特征。方法重组质粒pET32a ( )-SjCa8经诱导表达后,获取纯化蛋白SjCa8,利用ELISA、Western-blot和动物保护性实验检测SjCa8的免疫学特征。结果成功获取了纯化蛋白SjCa8,该蛋白能免疫识别血吸虫感染小鼠血清和血吸虫病患者血清。SjCa8免疫Balb/c小鼠可获得较高滴度的特异性抗体,诱导宿主产生35．31%的减虫率和35．68%的减卵率。结论纯化蛋白SjCa8具有良好的免疫原性和免疫反应性,具有作为血吸虫病免疫诊断和疫苗候选分子的研究价值。     

HIV-Associated Lymphoma of the Gastrointestinal Tract: The University of Toronto AIDS-Lymphoma Study Group Experience

We present a retrospective analysis of 31 (30 male) patients with HIV-associated gastrointestinal lymphoma which was undertaken to determine the natural history and response to therapy. Only seven patients had stage I or II lymphoma and 22 had stage IV. Pathology included diffuse large cell (13), immunoblastic (10), and small cell non-cleaved (7). The median age at presentation was 39 years (range 24-59), and the median CD4 count before treatment was 100/μL (range 4-1150). Eighty-seven percent of patients received systemic chemotherapy and significant response was seen in 84% (CR 38%; PR 46%). Hematologic toxicity was high (febrile neutropenia in 44% and dose reductions were required in 81%) and perforation occurred in five patients. Median survival for all patients was 6 months and death was secondary to lymphoma in 61%, treatment toxicity in 10%, other AIDS-related illnesses in 25% and other causes in 4%. Survival was shorter for patients with bone marrow involvement and for those with poor performance status. HIV-associated GI lymphoma has a poor prognosis despite good initial response to chemotherapy and is associated with a higher perforation rate than in HIV negative patients.     

几丁糖与人工骨联合应用预防椎板切除术后硬膜外粘连的实验研究

目的:观察椎板切除术后用几丁糖(CHT)的同时在椎板缺损处植入磷酸三钙人工骨(TCP)预防硬膜外瘢痕粘连的效果。方法:40只纯种日本大耳白兔随机分成A、B、C、D四组,制作L4椎板损伤模型。A组硬膜外涂布生理盐水,B组硬膜外涂布几丁糖,C组硬膜外覆盖人工骨,D组硬膜外涂布几丁糖的同时加人工骨覆盖。术后12周对椎板切除部位进行大体观察、组织学观察及生化检查,比较各组间瘢痕形成和粘连情况。结果:B、C、D组的改良Rydell-Balazs粘连韧度评分、胶原含量及改良Nussvaum组织学评分均优于A组(P<0.01),D组优于B组与C组(P<0.05),B组与C组无显著性差异(P>0.05)。结论:联合应用几丁糖和人工骨能有效预防硬膜外瘢痕粘连的形成,比单独应用几丁糖和人工骨预防效果好。     

DEET insect repellent: effects on thermoregulatory sweating and physiological strain

Insect repellents (e.g. N,N-diethyl-m-toluamide or DEET) applied to the skin can potentially interfere with sweat production and evaporation, thus increasing physiological strain during exercise-heat stress. The purpose was to determine the impact of 33% DEET lotion on sweating responses, whole body thermoregulation and thermal sensation during walking exercise in the heat. Nine volunteers (2 females, 7 males; 22.1 ± 4.9 years; 176.4 ± 10.0 cm; 79.9 ± 12.9 kg) completed 5 days of heat acclimation (45°C, 20% rh; 545 watts; 100 min/day) and performed three trials: control (CON); DEET applied to forearm (DEET_LOC, 12 cm²); and DEET applied to ~13% body surface area (DEET_WB,). Trials consisted of 30 min walking (645 watts) in 40°C, 20% rh environment. Local sweat rate (SR), onset and skin wettedness were measured in DEET_LOC, and heart rate (HR), rectal temperature (T _re), skin temperature (T _sk), RPE, and thermal sensations (TS) were measured during DEET_WB. No differences (p > 0.05) were observed between DEET_LOC versus CON, respectively, for steady state SR (1.89 ± 0.44 vs. 2.09 ± 0.84 mg/cm²/min), SR area under the curve (46.9 ± 11.7 vs. 55.0 ± 20.8 mg/cm²), sweating onset, or skin wettedness. There were no differences (p > 0.05) in HR, T _re, T _sk, Physiological Strain Index, RPE or TS between DEET_WB versus CON. DEET did not impact measures of local forearm sweating and when applied according to military doctrine, did not adversely impact physiological responses during exercise-heat stress. DEET can be safely worn during military, occupational and recreational activities in hot, insect infested environments.