膝关节挫伤的磁共振影像表现

目的 :探讨磁共振短时的反转恢复序列 (STIR)在膝关节骨挫伤中的临床应用。方法 :通过 32例膝关节外伤病例在常规SE序列、FSE序列和STIR序列中的影像表现 ,分析STIR序列的优越性。结果 :32例共 45个骨挫伤病灶 ,T1W发现 38个 (占 84% ) ,T2W发现 37个 (占 82 % ) ,STIR序列病灶全部显示( 1 0 0 % )。结论 :STIR序列对骨挫伤的敏感性较高 ,能显示微小的骨髓水肿 ,充血及骨小梁的微骨折及其周围的骨软骨、关节囊的细微变化 ,对膝关节外伤具有较高价值。     

Endoplasmic Reticulum Stress Induced Synthesis of a Novel Viral Factor Mediates Efficient Replication of Genotype-1 Hepatitis E Virus

Hepatitis E virus (HEV) causes acute hepatitis in many parts of the world including Asia, Africa and Latin America. Though self-limiting in normal individuals, it results in ~30% mortality in infected pregnant women. It has also been reported to cause acute and chronic hepatitis in organ transplant patients. Of the seven viral genotypes, genotype-1 virus infects humans and is a major public health concern in South Asian countries. Sporadic cases of genotype-3 and 4 infection in human and animals such as pigs, deer, mongeese have been reported primarily from industrialized countries. Genotype-5, 6 and 7 viruses are known to infect animals such as wild boar and camel, respectively. Genotype-3 and 4 viruses have been successfully propagated in the laboratory in mammalian cell culture. However, genotype-1 virus replicates poorly in mammalian cell culture and no other efficient model exists to study its life cycle. Here, we report that endoplasmic reticulum (ER) stress promotes genotype-1 HEV replication by inducing cap-independent, internal initiation mediated translation of a novel viral protein (named ORF4). Importantly, ORF4 expression and stimulatory effect of ER stress inducers on viral replication is specific to genotype-1. ORF4 protein sequence is mostly conserved among genotype-1 HEV isolates and ORF4 specific antibodies were detected in genotype-1 HEV patient serum. ORF4 interacted with multiple viral and host proteins and assembled a protein complex consisting of viral helicase, RNA dependent RNA polymerase (RdRp), X, host eEF1α1 (eukaryotic elongation factor 1 isoform-1) and tubulinβ. In association with eEF1α1, ORF4 stimulated viral RdRp activity. Furthermore, human hepatoma cells that stably express ORF4 or engineered proteasome resistant ORF4 mutant genome permitted enhanced viral replication. These findings reveal a positive role of ER stress in promoting genotype-1 HEV replication and pave the way towards development of an efficient model of the virus.     

Natural occurrence of aflatoxin B<Subscript>1</Subscript> in some Indonesian food and feed products in Yogyakarta in year 1998–1999

A survey was conducted between 1998–1999 to evaluate the level of aflatoxin B₁ (AfB₁) contamination in some selected Indonesian food products, mainly peanuts and peanut products for sale in supermarkets or traditional markets in Yogyakarta, Indonesia. Quantitative analysis was carried out on 118 samples using the ELISA (Enzyme-Linked Immunosorbent Assay) technique. The results indicate that (61.1%) samples were contaminated with AfB₁ at range 2.0 to 249.0 μg/kg. Approximately 50% of the baby food products analysed were contaminated with AfB₁ and the maximum level found was 7.0 μg/kg. In corn products and fermented products, AfB₁ was detected in 66.7 and 50.0% of samples, respectively. A level as high as 5.6 μg/kg of AfB₁ was found in the corn and 6.0 μg/kg in fermented product. AfB₁ was also detected in all rice products, feed products, and other processed products at levels of up to 7.0, 27.0, and 26.0 μg/kg, respectively.     

Joseph Basil Girard,an early botanical collector in Arizona

Girard, a career army surgeon, known as a botanical collector chiefly through a few citations by Rothrock (1879), proves to have collected a considerable series in Arizona, probably in 1874. The probable source of the specimens is discussed. The collection is now deposited at MICH.