Strong linkage disequilibrium of a HbE variant with the (AT)9(T)5 repeat in the BP1 binding site upstream of the β-globin gene in the Thai population

A binding site for the repressor protein BP1, which contains a tandem (AT)_x(T)_y repeat, is located approximately 530 bp 5 to the human -globin gene (HBB). There is accumulating evidence that BP1 binds to the (AT)₉(T)₅ allele more strongly than to other alleles, thereby reducing the expression of HBB. In this study, we investigated polymorphisms in the (AT)_x(T)_y repeat in 57 individuals living in Thailand, including three homozygotes for the hemoglobin E variant (HbE; 26Glu->Lys), 22 heterozygotes, and 32 normal homozygotes. We found that (AT)₉(T)₅ and (AT)₇(T)₇ alleles were predominant in the studied population and that the HbE variant is in strong linkage disequilibrium with the (AT)₉(T)₅ allele, which can explain why the ^E chain is inefficiently synthesized compared to the normal ^A chain. Moreover, the mildness of the HbE disease compared to other hemoglobinopathies in Thai may be due, in part, to the presence of the (AT)₉(T)₅ repeat on the HbE chromosome. In addition, a novel (AC)_n polymorphism adjacent to the (AT)_x(T)_y repeat (i.e., (AC)₃(AT)₇(T)₅) was found through the variation screening in this study.MIM and accession numbers and URLs for data presented herein are as follows: Online Mendelian Inheritance of Man (OMIM), (for HBB [MIM 141900]). GenBank, (accession number [NG_000007.2] reference sequence information).     

Morphometric comparison of human nerve cells: pyramidal motor system

We compared morphological and morphometric data on various motor neurons in the human pyramidal system using the modified Klüver-Barrera staining method with extremely minimized shrinkage ratio and an image-analyzer. We classified motor neurons in the human pyramidal system into three groups according to the measurement data. This report may be of interest to better understand the process of nerve conduction in the human pyramidal system.     

Effect of vitamin K2 on cortical and cancellous bones in orchidectomized young rats

OBJECTIVES: The purpose of the present study was to compare the effect of vitamin K(2) on cortical and cancellous bones in orchidectomized young rats. METHODS: Forty male Sprague-Dawley rats, 6 weeks of age, were randomized by stratified weight method into four groups with 10 rats in each group: baseline controls (BLC), age-matched controls (AMC), orchidectomy (ORX), and ORX+vitamin K(2) administration (K). Vitamin K(2) (menatetrenone) was administered subcutaneously twice a week at dose of 30 mg/kg each. The experimental period was 8 weeks, and cortical and cancellous bone histomorphometry was performed on the tibial shaft and the proximal tibia, respectively. RESULTS: Cortical area (Ct Ar) and cancellous bone volume (BV/TV) were significantly greater in the AMC group than in the BLC group. Ct Ar was significantly lower in the ORX group than in the AMC group, and cancellous BV/TV was also significantly lower in the ORX group than in the AMC group as a result of significantly increased eroded surface (ES/BS). Although Ct Ar in the ORX+K group did not differ significantly from that in the ORX group, cancellous BV/TV was significantly greater in the ORX+K group than in the ORX group, but still significantly lower than in the AMC group. This protective effect of vitamin K(2) on cancellous bone was attributable to normalizing increased ES/BS. CONCLUSIONS: Vitamin K(2) appears to act more strongly on cancellous bone than on cortical bone in ORX young rats. High dose vitamin K(2) could partially prevent the reduction of cancellous bone gain by normalizing raised bone resorption in ORX young rats.     

模糊ART神经网络在心律失常分析中的应用

本研究提出一种用模糊ART神经网络进行心律失常分析的方法。确定用于描述QRS波群特征的若干属性 ,提取其特征 ,模糊化处理后作为神经网络的输入模式矢量。神经网络为三层结构 ,经过竞争学习 ,对QRS波群进行自动分类。分类结果用MIT -BIH数据库进行了检验 ,证明本方法非常有效 ,30min数据的分析时间小于 2s,满足实用要求     

Triple synchronous neoplasms in one kidney: report of a case and review of the literature

We report the case of a patient with three synchronous but histologically different primary renal tumors that were all in the same kidney. Two tumors were different subtypes of renal cell carcinoma (RCC), and the third was a variant form of angiomyolipoma. The patient was a 62-year-old man who was receiving antihypertensive drugs and came to our hospital for a regular check-up. Ultrasonography performed during the visit revealed a left renal mass, but the patient had no related symptoms. Subsequent computed tomography revealed two round, high-density masses, one in the mid-portion and the other in the lower pole of the left kidney, and multiple cysts in the right kidney and the liver. The mass in the mid-portion measured 3.3 x 3.0 x 2.8 cm, and the mass in the lower pole measured 1.7 x 1.1 x 0.9 cm. A left radical nephrectomy was performed. On gross examination, an additional ovoid nodule (0.6 cm in the greatest dimension) was found in the lower pole. Microscopically, the largest tumor consisted of a broad alveolar arrangement of large round cells with abundant eosinophilic or clear cytoplasm, distinct cell borders, and perinuclear halos, features consistent with chromophobe RCC. The smallest tumor was a conventional (clear-cell) RCC. The third tumor was composed solely of atypical epithelioid cells with prominent nucleoli and yellowish-brown to black pigments. The tumor cells were positive for melanin (Fontana-Masson stain), the melanoma marker HMB45, vimentin, smooth-muscle actin, and the macrophage marker CD68 and were negative for cytokeratin. This tumor was considered a pigmented epithelioid type of angiomyolipoma. The histologic, histochemical, and immunohistochemical features in this case confirmed the presence of three synchronous primary tumors, a chromophobe and a clear-cell type RCC and a pigmented epithelioid angiomyolipoma, all of which were in the same kidney. This case is the first of its type reported in the literature.     

Isolation and mapping of a polymorphic CA repeat sequence at the human VRK1 locus

VRK1 is a novel human putative serine/threonine kinase, and is located on chromosome 14 at band q32 where an autosomal recessive congenital microphthalmia (CMIC) is mapped. We isolated a polymorphic dinucleotide CA repeat marker from a genomic clone containing the human VRK1 gene. This polymorphism will be useful in genetic studies of disorders localized at the 14q32 region, such as CMIC. Received: October 8, 1998 / Accepted: October 16, 1998     

过氧化物酶增殖体激活受体α在急性肺损伤大鼠肺组织的表达及其意义

目的: 观察内毒素(LPS)复制的急性肺损伤（ALI）大鼠肺组织过氧化物酶增殖体激活受体α（PPARα）表达的变化,探讨PPARα在ALI中可能的作用。方法: 将40只雄性Wistar大鼠随机分为对照组、LPS致伤1 h组、2 h组、4 h组和8 h组。用LPS(5 mg/kg) 静脉注射复制大鼠ALI模型，分别在LPS致伤后1 h、2 h、4 h、8 h时处死大鼠，测定各组肺组织湿/干重比（W/D）及肺组织病理变化；采用RT-PCR法检测肺组织中PPARα mRNA的表达；采用免疫组化法检测肺组织中PPARα的表达。结果: LPS致伤后2 h、4 h、8 h肺组织W/D均显著高于对照组（均P< 0.01）；LPS致伤后2h、4h PPARα mRNA表达分别显著低于对照组（均P < 0.01）；而LPS致伤4h和8h组PPARα表达阳性细胞数显著低于对照组（均P< 0.05）。结论: PPARα在ALI大鼠肺组织表达降低。表明PPARα在急性肺损伤的发病机制中具有重要作用。     

Unique properties of fetal lymphoid progenitors identified according to RAG1 gene expression

RAG1/GFP knockin mice were exploited to isolate and characterize fetal lymphoid progenitors. CD11b and IL-7Ralpha are expressed in a developmental stage-dependent fashion, revealing how substantial numbers of early lymphoid progenitors were discarded or neglected in previous studies. The myeloerythroid potential of fetal progenitors in clonal assays declined in synchrony with activation of the RAG1 locus but was not completely extinguished. Lymphoid differentiation corresponded to patterns of gene expression previously found for adult marrow, but no fraction of fetal liver was enriched with respect to B + T progenitors. Also, unlike adults, fetal lymphoid progenitors transiently expressed endothelial cell markers. These findings help to reconcile discrepancies in previous reports and suggest that the fetal immune system arises via unique mechanisms.     

Characterization of enteropathogenic and enteroaggregative Escherichia coli isolated from diarrheal outbreaks.

Virulence characteristics of diarrheal outbreak-associated Escherichia coli O55:NM, O126:NM, and O111:NM were examined. The E. coli O55:NM strains were atypical enteropathogenic E. coli (EPEC), while the E. coli O126:NM and O111:NM strains should be classified as enteroaggregative E. coli (EAggEC). The contributions of EPEC and EAggEC to the human disease burden in Japan might be significantly greater than is currently appreciated.     

Alterations in the INK4a/ARF locus and their effects on the growth of human osteosarcoma cell lines

Two different proteins, p16(INK4a) and p14(ARF), encoded by the INK4a/ARF locus play important roles in the RB and p53 pathways, respectively. This study was performed to determine genetic and epigenetic alterations in the INK4a/ARF locus and their effects on the growth of osteosarcoma. Among six cell lines examined, both p16(INK4a) and p14(ARF) exons were homozygously deleted in two cell lines, MG63 and HOS, and both p16(INK4a) and p14(ARF) promoters were methylated in one cell line, U2OS. Wild-type mRNA and proteins for p16(INK4a) and p14(ARF) were expressed in three other cell lines, SaOS2, HuO9, and G292. Transfection studies were performed using two cell lines, U2OS and MG63. Both the RB and p53 genes were wild types in U2OS, whereas p53 but not RB was mutated in MG63. Both p16(INK4a) and p14(ARF) suppressed the growth of U2OS, whereas p16(INK4a) but not p14(ARF) suppressed the growth of MG63. p53 only did not suppress the growth of MG63 either; however, coexpression of p14(ARF) with p53 increased the fraction of the G0/G1 phase in MG63 cells. The data presented here demonstrate the importance of genetic and epigenetic alterations in the INK4a/ARF locus for the growth of osteosarcoma and thus will be useful to further understand the biologic behavior of osteosarcoma in association with the defects in the p53 and RB pathways.