Features of pediatric head injury in Hong Kong

Head injury in children causes special concern in most communities. From 1989 to 1994, 2,785 children younger than 16 years old were admitted to our neurosurgical service because of head injury. Fall from a height was the major cause of head injury leading to admission in infants and children in preschool age groups, whereas traffic-related or bicycle-related accidents were more likely to be the cause of head injury for those aged 11–15 years. In all age groups there was a male preponderance. The overall mortality was 0.6%. Traffic-ralated accidents caused more severe injury and accounted for 67% of all fatalities. For patients under 6 years old, about 40% of head injuries occurred at home. Preventive measures for pediatric head injury in Hong Kong are suggested.     

Topoisomerase II-mediated DNA cleavage by amonafide and its structural analogs

Treatment of SV40-infected monkey cells with amonafide (benzisoquinolinedione), an intercalative antitumor drug, resulted in rapid accumulation of linearized intracellular SV40 DNA molecules that were protein linked. Studies using purified mammalian DNA topoisomerase II have shown that amonafide and its structural analogs interfere with the breakage-rejoining reaction of the enzyme by stabilizing a reversible enzyme-DNA "cleavable complex." Denaturation of the cleavable complex with sodium dodecyl sulfate resulted in DNA cleavage and the covalent association of topoisomerase II polypeptides with the cleaved DNA. Unwinding measurements indicate that amonafide is a DNA intercalator. These results suggest that amonafide and its structural analogs (e.g., mitonafide) represent a new class of intercalative topoisomerase II-active antitumor drugs. Different from other topoisomerase II-active antitumor drugs, amonafide and mitonafide induce specific DNA cleavage at a single major site on pBR322 DNA. The strong site specificity of amonafide may allow detailed characterization of the intercalator-stabilized, topoisomerase II-DNA cleavable complex.     

Invasive pulmonary aspergillosis: high incidence of disseminated intravascular coagulation in fatal cases.

BACKGROUND AND PURPOSE: Disseminated intravascular coagulation (DIC) is a rarely described finding in invasive pulmonary aspergillosis (IPA) with unclear impact on mortality. METHODS: This study included patients with positive cultures of Aspergillus spp. from respiratory specimens, serological evidence of aspergillosis, or lung biopsy findings supporting aspergillosis treated at National Taiwan University Hospital from January 1999 to June 2005. IPA was defined based on the consensus of the European Organization for Research and Treatment of Cancer, and the Mycosis Study Group of the National Institute of Allergy and Infectious Diseases. Univariate logistic regression analysis was used to evaluate the factors associated with mortality. RESULTS: Proven or probable IPA was diagnosed in 26 patients. Hematological malignancy was found in 11 patients (42%) and immunosuppressive agents had been administered to 17 patients (65%). Among 20 culture-proven infections (77%), the most frequently encountered fungi were Aspergillus fumigatus (46%) and Aspergillus flavus (23%). The overall mortality rate was 62%. Univariate and multivariate analyses revealed that DIC was the only factor that was significantly associated with death attributable to IPA (p<0.01). CONCLUSIONS: IPA is associated with a high mortality rate, particularly for patients with DIC.     

Neurotrophic effects of hippocampal target cells on developing septal cholinergic neurons in culture

The influence of hippocampal target cells on the development of cholinergic septal neurons was studied in rotation-mediated reaggregating cell cultures. Brain cells from 15-day-old mouse embryos were obtained from: septum, containing cholinergic cells which project to the hippocampus; hippocampus which contains target cells for the septal cholinergic neurons; and cerebellum, containing cells which are not targets for the septal cholinergic cells. The cells were then cultured for 3 weeks in a rotary incubator in the following combinations: septal cells alone; hippocampal cells alone; cerebellar cells alone; septal-hippocampal cells together; and septal-cerebellar cells together. After harvesting, fixation, and embedding, 50 micron sections were cut and processed for visualization of acetylcholinesterase activity. Sections from reaggregates containing either hippocampal or cerebellar cells alone contained only a few acetylcholinesterase-positive cells, but no positive fibers. Sections from septal-hippocampal coaggregates revealed a pattern of well-defined, fine-caliber acetylcholinesterase-positive fibers with extensive arborizations and varicosities suggesting axonal proliferation. In septal-cerebellar coaggregates, acetylcholinesterase-positive fibers appeared to be degenerating and distinct areas were observed which were essentially devoid of acetylcholinesterase fibers. In some experiments, either cerebellar or hippocampal cells were labeled with wheatgerm agglutinin-rhodamine prior to culture in order to identify these cells in the resulting reaggregates. Analysis of sections from these studies showed that acetylcholinesterase fibers were excluded from regions of coaggregates containing cerebellar cells, but were present in regions of coaggregates containing hippocampal cells. Finally, cell counts of acetylcholinesterase-positive cells in the various combinations revealed that these putative cholinergic neurons were significantly more numerous in septal-hippocampal coaggregates (271 +/- 19 per 10(6) septal cells added) than in septal reaggregates (38 +/- 6 per 10(6) septal cells added) or septal-cerebellar coaggregates (85 +/- 29 per 10(6) septal cells added). These results, taken together, suggest that hippocampal target cells influence the development and survival of cholinergic neurons.     

玻璃体切除术治疗外伤性眼内炎62例

0　引言　外伤性眼内炎是眼外伤的常见并发症 ,对视力及眼球威协极大 .由于病原体随致伤物直接进入眼内 ,在眼内和玻璃体繁殖 ,产生剧烈炎症反应 ,对眼内组织造成严重破坏 .如不及时而有效的控制 ,终使视力丧失 ,眼球萎缩 .近年随着现代玻璃体手术的发展 ,外伤性眼内炎的治愈率明显提高 .现将我科收治的 6 2例报告如下 .1　对象和方法1 .1　对象 1 996 - 0 6 / 1 998- 0 6我院连续收治 6 2例外伤性眼内炎 ,其中男 5 0例 ,女 1 2例 ,年龄 2～ 45岁 ,平均 1 6 .5岁 .1 4岁以下儿童 38例 ,占 6 1 .3% .以致伤原因分类 :角膜穿通伤30例 ,巩膜穿…     

Stromal‐derived factor‐1 gene variations in pediatric patients with primary immune thrombocytopenia

Primary immune thrombocytopenia (ITP) of childhood is an autoimmune disease characterized by abnormally increased destruction of platelets and decreased megakaryopoiesis. Stromal‐derived factor‐1 (SDF‐1) plays a role in megakaryopoiesis and may be involved in the pathogenesis of ITP. Five single nucleotide polymorphisms (SNPs) of the SDF‐1 gene, including rs1801157, rs2839693, rs2297630, rs1065297, and rs266085, were assessed in 100 children with ITP and 126 healthy controls. The genotypes were analyzed by tetra ARMS polymerase chain reaction and confirmed by direct sequencing. Compared with controls, the rs2839693 A/A and rs266085 C/T genotypes were decreased in ITP patients (P = 0.004 and 0.007, respectively). The odds ratios of the latter genotypes were 0.48, 95% CI 0.28–0.82. Further analysis of the relationship between SDF‐1 polymorphisms and clinical features showed that rs2297630 A/G was associated with protection from chronicity (P = 0.002; OR, 0.07; 95% CI, 0.01–0.61) and steroid dependence (P = 0.007; OR, 0.10; 95% CI, 0.01–0.84) in ITP patients. However, rs266085 genotype C/C was associated with risk of steroid dependence (P = 0.012, OR 3.87, 95% CI 1.27–11.77). The findings of this study suggest that SDF‐1 gene variations may be associated with the occurrence and prognosis of childhood ITP.