Cardiac biopsy in childhood

Endomyocardial biopsy was attempted in 18 children aged 5 months to 15 years with 82% success. Biopsies obtained from 15 children were examined by light and electron microscope making positive morphological diagnoses in 3 cases. The biopsy findings were actively helpful in 7 other cases, which contrasts with experience in adult biopsy series. This is a low risk procedure which does not add to the hazards of cardiac catheterization in children.     

Prolonged QT interval and cardiac arrhythmias in two neonates: sudden infant death syndrome in one case

Two neonates with arrhythmias and the long QT syndrome are described. The arrhythmias were detected in utero and both infants were apparently well after birth. The first infant, although well, had a bradycardia for the first 9 days of life. A normal heart rate was documented at 10 days but a prolonged QT interval was not appreciated on the ECG. He was discharged from hospital but died suddenly and unexpectedly 3 days later. A post-mortem examination failed to find a cause for his death which therefore fell into the category of the sudden infant death syndrome (SIDS). A retrospective analysis of the perinatal electrocardiogram showed a probable junctional rhythm with 2:1 conduction to the ventricle; the QT interval was prolonged at 0.52 seconds (QTC = 0.63). The second infant had a QT interval of 0.52 seconds (QTC = 0.54) and frequent ventricular premature beats on a 24-hour electrocardiogram. She was treated with propranolol and remains well 2 years later. Sudden infant death has often been described in the siblings of children with the long QT syndrome and one other report described a case of SIDS which was said to have had a prolonged QT interval on the perinatal ECG. This report, however, provides unquestionable evidence, in one case, of an association between the long QT syndrome and SIDS.     

13Carbon mixed triglyceride breath test and pancreatic enzyme supplementation in cystic fibrosis

Children with cystic fibrosis have variable degrees of exocrine pancreatic insufficiency which, if untreated, is the main cause of fat malabsorption. The impact of pancreatic enzyme supplementation on fat digestion was measured in 41 children with cystic fibrosis, 11 healthy controls, and five children with mucosal diseases by a non-invasive test of intraluminal lipolysis using 13carbon (13C) labelled mixed triglyceride (1,3-distearyl, 2[13C] octanoyl glycerol). The children with cystic fibrosis without pancreatic supplements had a median (range) 13C cumulative percentage dose recovered over six hours (cPDR) of 3.1% (0-31.7), the controls 31.0% (21.8-41.1), and the subjects with mucosal disease 27.8% (19.7-32.5). In 23 subjects with cystic fibrosis the usual dose of pancreatic enzyme supplements increased the cPDR to a median of 23.9% (0-45.6), and twice the usual dose of enteric coated microspheres increased the cPDR to 31.1% (11.1-47.8). There was no significant difference between the median cPDR of normal controls and children with mucosal disease, but there was a highly significant difference between these groups and children with untreated cystic fibrosis. Thirteen children with cystic fibrosis had no 13C recovery in their breath without enzymes and 10 showed marked increases with regular enzymes. In eight children doubling the dose of enzymes caused no or minimal improvement. The mixed triglyceride breath test offers a simple, non-invasive way of assessing the need for pancreatic enzyme supplementation in children with cystic fibrosis and could be used to optimise treatment.     

The Emergence of Clinically Abnormal Levels of Cardiovascular Disease Risk Factor Variables Among Young Adults: The Bogalusa Heart-Study

Background. The Bogalusa Heart Study, a long-term epidemiologic investigation of the early natural history of atherosclerosis, was conducted for the first time in 1973-1974 on children from birth through the age of 14 in a biracial (black-white) population. Methods. The emergence of clinically recognizable abnormalities (obesity, hypertension, and hyperlipidemia) was studied in 1,928 young adults, ages 19-32 years, examined in the 1988-1991 survey. Results. The occurrence of morbid levels of cardiovascular disease risk factors varied by race and gender. The prevalence of severe overweight, body mass index ≥ 31.1 kg/m² for males and ≥ 32.3 kg/m² for females, was much higher for black women (20.1%) than for white women (8.7%), black men (14.0%), or white men (11.7%). The frequency of hypertension [systolic blood pressure (BP) ≥ 140 mm Hg, diastolic BP ≥ 90 mm Hg, or treatment for high BP] was greatest for black women (13.9%) versus black men (10.1%), white men (6.2%), or white women (5.0%). Approximately 9.5% of the men and 6% of the women had elevated LDL cholesterol (≥160 mg/dl), while elevated triglycerides (≥250 mg/dl) ranged from 0% in black females to 7.4% in white males. Dyslipoproteinemia related to HDL cholesterol (≤35 mg/dl) was more marked among white men (16%) compared with the other groups (approximately 4%). Correlations for risk factors in a subgroup of 1,587 individuals initially surveyed as children in 1973-1974 were examined as an indication of tracking over a 15-year period. Highly significant correlations were seen for obesity, blood pressure, and LDL cholesterol. Conclusion. Early identification of adverse levels of cardiovascular disease risk factors defined by clinical experience should help to predict and prevent future cardiovascular disease morbidity and mortality.     

Biomonitoring of mercury and persistent organic pollutants in Michigan urban anglers and association with fish consumption

The 32-mile Detroit River and surrounding tributaries have been designated as a Great Lakes Area of Concern due to pollution from decades of municipal and industrial discharges, sewer overflows and urban development. Key pollutants in fish samples from the Detroit River include mercury, polychlorinated biphenyls (PCBs), dichlorodiphenyldichloroethylene (DDE), dioxins and furans. A biomonitoring study was conducted to assess exposures to these persistent toxic substances in Detroit urban shoreline anglers who may be at high exposure risk due to consumption of locally caught fish. Using a modified venue-based sampling approach, 287 adult shoreline anglers along the Detroit River were recruited and participated in the program. Study participants provided blood and urine specimens and completed a questionnaire following informed consent. We examined percentile estimates for total blood mercury, PCBs, DDE, and dioxin-like total toxic equivalency (TEQ) concentrations among study participants. Multiple linear regression was used to identify important predictors of contaminant concentrations. Participants consumed a median of 64 Detroit River caught fish meals in the past year. The Detroit urban anglers’ median total blood mercury concentrations was 3.2 times higher than that for the general adult U.S. population. PCB concentrations among the Detroit anglers aged 18–39 years were higher than the U.S. population of the same race/ethnicity. Elevated levels of DDE and total TEQ concentrations were not observed in the cohort. Eating more locally caught fish was associated with higher total blood mercury and serum PCB concentrations. The biomonitoring data served to inform public health officials and help guide environmental public health actions to reduce harmful exposures.     

纤维粘连蛋白基因多态性与尘肺易感性的研究

目的 探讨纤维粘连蛋白(FN)4个基因位点多态性与尘肺发病的关系.方法 以确诊的128例汉族男性Ⅰ期尘肺患者作为病例组,选择与病例组年龄相差不超过5岁、同性别、同民族、开始接尘时间及累积接尘工龄相差不超过2年、在同一车间或同一采掘工作面工作的非尘肺接尘工人为对照.采Ⅲ聚合酶链反应-限制性片断长度多态件分析(PCR-RLFP)的方法 检测FN基因HaeⅢb、Msp Ⅰ、HindⅢ、Taq Ⅰ b位点的基因型.结果 病例组携带Msp Ⅰ野牛基因型(CC)频率和等位基C的分布频率分别为10.9%和41.8%,明显高于对照组(分别为3.9%和31.2%),差异有统计学意义(P<0.05).病例组携带HaeⅢb野生基因型(AA)的频率为24.2%,明显高于对照组(17.9%),差异行统计学意义(P<0.05);病例组HaeⅢbA等位基因频率为51.9%,明显高于对照组(42.2%),差异有统计学意义(P<0.05).病例组和对照组Taq Ⅰb位点基因型和Hind Ⅲ位点基因型的分布频率比较,筹异均无统计学意义(P>0.05).病例组同时携带Msp Ⅰ cc和HaeⅢbAA基因型的频率明显高于对照组,差异行统计学意义(P<0.05).结论 携带FN Msp Ⅰ cc和Hae Ⅲ b AA基冈型的接尘工人患尘肺的危险性增加,同时携带这2种基因型的接尘工人更易患尘肺.未发现FN Taq Ⅰ b和HindⅢ位点基因多态性与尘肺易感性有关.     

硫酸锌对高脂喂养载脂蛋白E基因敲除小鼠主动脉基质金属蛋白酶-9和CD40表达的影响

目的探讨硫酸锌对高脂喂养载脂蛋白E（ApoE）基因敲除小鼠血脂和氧化低密度脂蛋白（oxLDL）水平,及主动脉中基质金属蛋白酶9（MMP-9）和细胞分化抗原40（CD40）mRNA表达的影响。方法 AopE基因敲除小鼠连续14周喂饲高脂饲料,同时分别给予小鼠浓度为2.5、25 mmol/L硫酸锌水溶液作为低剂量组和高剂量组。测定小鼠血脂和oxLDL水平,并测定主动脉中MMP-9和CD40 mRNA表达水平。结果低剂量组和高剂量组小鼠血清中甘油三酯和oxLDL水平明显低于动脉粥样硬化（AS）模型组（P〈0.01）。低剂量组和高剂量组小鼠主动脉MMP-9 mRNA和CD40 mRNA水平与AS模型组没有差异。结论补充硫酸锌降低了AS模型动物的甘油三酯和oxLDL水平,具有潜在的抗AS作用,但对主动脉MMP-9和CD40 mRNA表达无影响。     

食管鳞癌患者外周血T淋巴细胞亚群的变化

目的研究食管鳞癌患者外周血T淋巴细胞亚群的变化特点。方法采用流式细胞技术，对108例食管鳞癌患者（食管鳞癌组）术前检测其外周血T淋巴细胞亚群水平，并与50例健康献血者（对照组）对比，分析食管鳞癌患者T淋巴细胞亚群的变化特点。结果（1）与对照组比较，食管鳞癌组患者外周血CD3^＋ 、NK细胞水平差异无统计学意义（P=0．890；P=0．320）；CD4^＋和CD8^＋水平显著增高（P=0．001；P〈0．001），由于CD8^＋增高的程度大于CDZ增高的程度，使得CDgCDs~较对照组降低（P〈0．001）。（2）早期食管鳞癌患者外周血CD4^＋/CD8^＋低于对照组，但差异无统计学意义（P=0．112）；中晚期食管鳞癌患者CDgCDs~进一步降低，与对照组比较差异有统计学意义（P〈0．001），但与早期食管鳞癌患者相比，差异无统计学意义（P=0．218）。（3）有淋巴结转移食管鳞癌患者CD4^＋和CD4^＋/CD8^＋均低于无淋巴结转移患者（P均〈0．001），CD8^＋和NK细胞均高于无淋巴结转移患者，差异均有统计学意义（P=0．002；P=0．005）。结论食管鳞癌患者存在免疫功能低下，随着肿瘤的进展免疫功能进一步受到削弱；监测CD4^＋/CD8^＋的变化可作为食管鳞癌病情进展的标志之一。     

Acute hazardous substance releases resulting in adverse health consequences in children: Hazardous Substances Emergency Events Surveillance system, 1996-2003

Because of their small size and ongoing organ development, children may be more susceptible than adults to the harmful effects of toxic chemicals. The objective of the study reported here was to identify frequent locations, released substances, and factors contributing to short-term chemical exposures associated with adverse health consequences experienced by children. The study examined the Hazardous Substances Emergency Events Surveillance (HSEES) system data from 1996-2003. Eligible events involved the acute release of a hazardous substance associated with at least one child being injured. The study found that injured children were predominantly at school, home, or a recreational center when events took place. School-related events were associated with the accidental release of acids and the release of pepper spray by pranksters. Carbon monoxide poisonings occurring in the home, retail stores, entertainment facilities, and hotels were responsible for about 10 percent of events involving child victims. Chlorine was one of the top chemicals harmful to children, particularly at public swimming pools. Although human error contributed to the majority of releases involving child victims, equipment failure was responsible for most chlorine and ammonia releases. The authors conclude that chemical releases resulting in injury to children occur mostly in schools, homes, and recreational areas. Surveillance of acute hazardous chemical releases helped identify contributing causes and can guide the development of prevention outreach activities. Chemical accidents cannot be entirely prevented, but efforts can be taken to provide safer environments in which children can live, learn, and play. Wide dissemination of safety recommendations and education programs is required to protect children from needless environmental dangers.