Granulocytic sarcoma of the brain: a case report and review of the literature

Granulocytic sarcoma (chloroma), a rare tumor usually associated with myelogenous leukemia, is capable of invading the meninges or brain parenchyma. Radiologic findings in a case of granulocytic sarcoma of the brain, as well as those in 11 previously reported cases of intracranial leukemic masses, are interpreted. On computed tomographic scans, the lesions can appear isodense or hyperdense, edema and necrosis are variable, and there is uniform enhancement following intravenous administration of contrast material. There may be some affinity for the posterior fossa.     

Bone Mass and Strength in School‐Age Children Exhibit Sexual Dimorphism Related to Differences in Lean Mass: The Generation R Study

Bone strength, a key determinant of fracture risk, has been shown to display clear sexual dimorphism after puberty. We sought to determine whether sex differences in bone mass and hip bone geometry as an index of strength exist in school‐age prepubertal children and the degree to which the differences are independent of body size and lean mass. We studied 3514 children whose whole‐body and hip scans were measured using the same densitometer (GE‐Lunar iDXA) at a mean age of 6.2 years. Hip dual‐energy X‐ray absorptiometry (DXA) scans underwent hip structural analyses (HSA) with derivation of bone strength indices. Sex differences in these parameters were assessed by regression models adjusted for age, height, ethnicity, weight, and lean mass fraction (LMF). Whole‐body bone mineral density (BMD) and bone mineral content (BMC) levels were 1.3% and 4.3% higher in girls after adjustment by LMF. Independent of LMF, boys had 1.5% shorter femurs, 1.9% and 2.2% narrower shaft and femoral neck with 1.6% to 3.4% thicker cortices than girls. Consequent with this geometry configuration, girls observed 6.6% higher stresses in the medial femoral neck than boys. When considering LMF, the sexual differences on the derived bone strength indices were attenuated, suggesting that differences in muscle loads may reflect an innate disadvantage in bone strength in girls, as consequence of their lower muscular acquisition. In summary, we show that bone sexual dimorphism is already present at 6 years of age, with boys having stronger bones than girls, the relation of which is influenced by body composition and likely attributable to differential adaptation to mechanical loading. Our results support the view that early life interventions (ie, increased physical activity) targeted during the pre‐ and peripubertal stages may be of high importance, particularly in girls, because before puberty onset, muscle mass is strongly associated with bone density and geometry in children. © 2015 American Society for Bone and Mineral Research.     

Increased myocardial methionine‐enkephalin with reduced arterial oxygenation in congenital heart disease

Background: Cardiac opioid peptides have been identified to exert important adaptive metabolic signalling for cardioprotection against ischaemia or hypoxia‐related injury. Aims: To determine myocardial methionine‐enkephalin content in children with hypoxemic congenital heart defects and to correlate myocardial content of methionine‐enkephalin with the extent of arterial oxygen desaturation. Methods: Children (n= 20, median age of 16 months), undergoing cardiac surgical repair (tetralogy of Fallot, 17/20), were included in this study. Arterial oxygen saturation was measured on admission. Myocardial samples obtained during surgery were assayed via radioimmunochemistry for methionine‐enkephalin content. Results: Greater methionine‐enkephalin content was measured in the right ventricles of the patients suffering from recent cyanotic spells compared with those with no recent spells (cyanotic spells: 2418 ± 844 pg/g wet weight tissue, n= 6; no spells: 1175 ± 189 pg/g wet weight tissue, n= 14, P= 0.04). An inverse correlation was evident between the arterial oxygen saturation and myocardial methionine‐enkephalin content. Conclusion: Myocardial methionine‐enkephalin levels increase with the severity of hypoxic stress in congenital cardiac disease and may play an important adaptive role in countering adrenergic over‐activity and related excess demand on myocardial metabolic capacity.     

广州市12~13岁儿童牙龈炎与恒牙龋患病关系的调查分析

【目的】 探讨儿童牙龈炎与恒牙龋的相关关系,为儿童牙龈炎防治工作提供理论依据。 【方法】 采用多阶段分层整群随机抽样的方法共调查广州市12~13岁儿童1 115人。检查方法和标准参考1997年WHO推荐的《口腔健康调查基本方法》,牙龈炎检查六颗指数牙,龋病检查全口恒牙,分别采用牙龈指数(GI)和DMFT记录检查结果。Logistic回归分析儿童牙龈炎与恒牙龋病的关系。 【结果】 广州市12~13岁儿童牙龈炎患病率72.65%,中、重度牙龈炎患病率分别为28.16%和5.83%。恒牙龋患病率为25.83%,其中未充填龋占龋齿的73.73%。Logistic回归分析显示未充填龋是广州市12~13岁儿童牙龈炎患病的危险因素。 【结论】 广州市12~13岁儿童牙龈炎患病率较高,有未充填龋存在的儿童是广州市儿童牙龈炎重点防治人群。     

Biocompatibility of hydroxylated metabolites of BISGMA and BFDGE

Unpolymerized dental monomers can leach out into the oral biophase and are bioavailable for metabolism. We hypothesize that metabolites would be less toxic than parent monomers. We first identified the formation of metabolites from bisphenol F diglycidyl ether (BFDGE) and Bisphenol A glycidyl methacrylate (BISGMA) after their exposure to liver S9 fractions. Then, the metabolites and parent compounds were subjected to in vitro cytotoxicity, mutagenicity, and estrogenicity studies. Bisphenol A bis(2,3-dihydroxypropyl) ether and bisphenol F bis(2,3-dihydroxypropyl) ether were the hydroxylated metabolites of BISGMA and BFDGE, respectively. Cytotoxicity against L929 cells showed that the metabolites were significantly (p < 0.05) less cytotoxic than the parent monomers. Only BFDGE was mutagenic in the Ames assay with strain TA100 of Salmonella typhimurium. Parent and metabolite compounds did not stimulate estrogen-dependent MCF-7 cell proliferation above solvent controls. These results indicated that the hydroxylated metabolites were non-mutagenic, non-estrogenic, and less cytotoxic than their parent monomers.     

Selective inhibition of murine palatal mesenchymal cell proliferation in vitro by secalonic acid D.

Secalonic acid D (SAD), a teratogenic mycotoxin, induces cleft palate (CP) in the offspring of exposed mice by inhibiting palatal shelf growth. Since reduced proliferation, increased apoptosis, and/or decreased extracellular matrix (ECM) synthesis of palatal mesenchymal cells (PMC) can all contribute to smaller shelf size, the hypothesis that teratogenically relevant concentrations (0 to 120 microg/ml) of SAD will have adverse effects on one or more of these cellular processes was tested, using primary murine PMC cultures. Exposure to SAD resulted in significant and dose-dependent decreases in mesenchymal cell number, uptake of (3)H-thymidine, and expression of proliferating cell nuclear antigen (PCNA). Trypan blue dye exclusion assay, however, revealed significant cell death only at higher doses, suggesting that the decrease in cell number at lower (more realistic) doses is likely a consequence of reduced cell proliferation and not cell death. Further, negative results in the DNA fragmentation analysis following SAD exposure suggested that cell death caused by higher levels of SAD was unrelated to apoptosis. Similarly, results of (3)H-glucosamine uptake assay indicated inhibitory effect of SAD on accumulation of hyaluronic acid (HA) or sulfated glycosaminoglycans (sGAG) only at the highest dose tested. Also, SAD affected neither extracellular nor cell-associated fibronectin expression at any dose tested. Taken together, these data suggest that the pathogenesis of CP by SAD is likely a result of a reduction in the size of the palatal shelf caused by SAD-induced inhibition of mesenchymal cell proliferation.     

Air pollution exposure estimation using dispersion modelling and continuous monitoring data in a prospective birth cohort study in the Netherlands

Background

High temperature and humidity conditions are associated with short-term elevations in the mortality rate in many United States cities. Previous research has quantified this relationship in an aggregate manner over large metropolitan areas, but within these areas the response may differ based on local-scale variability in climate, population characteristics, and socio-economic factors.

Methods

We compared the mortality response for 48 Zip Code Tabulation Areas (ZCTAs) comprising Philadelphia County, PA to determine if certain areas are associated with elevated risk during high heat stress conditions. A randomization test was used to identify mortality exceedances for various apparent temperature thresholds at both the city and local scale. We then sought to identify the environmental, demographic, and social factors associated with high-risk areas via principal components regression.

Results

Citywide mortality increases by 9.3% on days following those with apparent temperatures over 34°C observed at 7:00 p.m. local time. During these conditions, elevated mortality rates were found for 10 of the 48 ZCTAs concentrated in the west-central portion of the County. Factors related to high heat mortality risk included proximity to locally high surface temperatures, low socioeconomic status, high density residential zoning, and age.

Conclusions

Within the larger Philadelphia metropolitan area, there exists statistically significant fine-scale spatial variability in the mortality response to high apparent temperatures. Future heat warning systems and mitigation and intervention measures could target these high risk areas to reduce the burden of extreme weather on summertime morbidity and mortality.