The problem of obesity among adolescents in Hong Kong: a comparison using various diagnostic criteria

Background  

Obesity is now a global epidemic. In this study, we aimed to assess the rates of obesity using several major diagnostic criteria in Chinese school adolescents in Hong Kong.     

The use of Bi-level positive pressure ventilation in the treatment of acute respiratory failure within the emergency department

Acute respiratory failure (ARF) is one of the eight leading causes of death for over 65-year-olds in Australia. Bi-level positive pressure (BiPAP) ventilation is the preferred form of non-invasive ventilation in the treatment of acute respiratory failure in the emergency department (ED) because, when used appropriately, it reduces the need for intubation. The patient on whom BiPAP is applied is able to protect their own airway, remaining cooperative with a normal mental state. In this paper, I explain acute respiratory failure, the appropriateness of BiPAP in the treatment of ARF, patient selection and exclusion from BiPAP treatment, current practice and recommendations for future practice. While BiPAP is commonly used in Australian EDs as part of the treatment of acute respiratory failure, evidence supporting its use is limited and more high level research is recommended.     

4-S-(5-酰氨基-1,3,4-噻二唑-2-基)-4-脱氧-4′-去甲基表鬼臼毒素衍生物的合成与抗肿瘤活性

基于在4′-去甲基表鬼臼毒素母核C₄位上联结含有杂原子的芳香环取代基,以此考察其结构与活性关系的设想,设计并合成了10个标题化合物。体外L₁₂₁₀白血病细胞与KB细胞生长抑制试验结果表明,这类化合物有较强的抗肿瘤活性。其中化合物SIPI-92-1772,1774,1775,1776,1777与1779的活性超过临床用药依托泊甙。其余化合物活性与依托泊甙相当或略低。     

4-(2-酰胺基-2-乙氧羰基)乙硫基-4-脱氧-4′-去甲表鬼臼毒素衍生物的合成与抗肿瘤活性

为考察4′-去甲基表鬼臼毒素4位上取代基结构变化与抗肿瘤活性的关系,设计并合成了23个标题化合物。体外L₁₂₁₀白血病细胞与KB细胞生长抑制试验的结果表明,化合物11,16和18的抗肿瘤活性超过依托泊甙,化合物8的活性与依托泊甙相当。     

Characterization of human marrow stromal cells: role in progenitor cell binding and granulopoiesis

Adherent cell layers and their associated extracellular matrices form when human marrow is incubated in cultures containing hydrocortisone and horse serum. These stromal layers contain cells positive for alkaline phosphatase; secrete collagens types I and III and fibronectin, bind the anti-actin monoclonal antibodies (MoAbs) HHF and CGA-7; stain with oil red O, and express the acetylated LDL receptor. Highly purified CD34 (My10)-positive progenitor cells attach to these stromal layers, and a 16-fold enrichment of CFU-GM in both stromal attachment and semisolid agar assays was observed. Granulopoiesis persisted up to 40 days (mean duration 25 days) after passaged stroma were recharged with stromal cell-depleted target cells in a two-stage liquid marrow culture system. Although equal to marrow fibroblasts in their ability to bind CD34+ myeloid progenitors, stromal layers were better at supporting granulopoiesis. This system provides an in vitro model to characterize the components of stroma and stroma-cytomatrix that enhance marrow progenitor cell localization and maintenance.     

Estimation of the number of hematopoietic precursor cells during fetal mouse development by covariance analysis

Differentiation of hematopoietic precursor cells results in the formation of clonally related descendent cells. Using the mosaic expression of beta-galactosidase in female mouse fetuses heterozygous for an X-linked lacZ transgene, we analyzed the clonal relationship of the hematopoietic progeny. The proportion of beta-galactosidase positive cells for different T- and B-lymphoid and myeloid cell populations was determined at different stages of fetal development. We found excellent correlations of the proportion of beta-galactosidase expressing cells for all hematopoietic lineages confirming that they share a common ancestry. Therefore, it was possible to estimate the number of common precursor cells (PC) based on binomial distribution and covariance analysis of pairs of different hematopoietic cell populations. Our results obtained from hematopoietic cells at 15.5 to 18.5 days of gestation indicated the presence of 15 to 18 lymphoid and 18 to 22 myeloid/lymphoid specific precursor cells. Statistical analysis of the precursor cell numbers showed a trend of increasing numbers that was highly significant. The precursor cell number was inversely related to maturity of the cell populations analyzed; ie, the lowest number of lymphoid and lymphoid/myeloid precursors was calculated when the most mature CD3+ T-cell population was used for comparison. Determination of PC numbers can therefore be used to assess the relative maturity and developmental potential of individual cell populations.     

EPP:一个与表情特征加工相关的ERPs晚期正成分

目的 研究与表情特征加工相关的事件相关脑电位（event-related potentials，ERPs）成分。方法 被试者为12名（7男5女）右利手健康大学生。刺激包括3种卡通面孔（中性、微笑、愤怒）和3种非面孔。要求被试者进行面孔识别（face recognition，FR）和面孔表情分类（facial expression classification，FEC）2种作业。记录32导脑电。结果 1）与FR任务相比，FEC任务产生明显的P580成分；2）FEC的ERP与FR的ERP的差异波形，表现出一个非常明显的中央一顶区分布的正差异（450～850ms），命名为表性加工正成分（expression processing positivity，EPP）；3）EPP的峰值潜伏期表现出明显的表情特征主效应，以愤怒面孔EPP的潜伏期最短，微笑面孔EPP的潜伏期最长。结论 EPP可能反映了表情特征的晚期加工。