Changes in HIV-1 incidence in heroin users in Guangxi Province, China

Guangxi Province, China recently experienced an outbreak of HIV-1 infection among heroin users. We studied HIV-1 incidence rates and associated risk factors for HIV-1 infection among heroin users residing in Pingxiang City. A total of 318 heroin users were followed from February 1998 through January 1999 (median follow-up: 8.1 months). Of these, 130 were prospectively followed from January through September 1999 (median follow-up: 8.3 months). HIV-1 and hepatitis C virus (HCV) incidence rates for each period were calculated. A generalized estimating equation approach was implemented to identify independent risk factors associated with HIV-1 infection across both periods. Among 318 study participants, 97.2% were men. The median age was 22 years. Approximately 60% reported sharing needles. HIV-1 prevalence at baseline was 15.4%. During the first follow-up period, HIV-1 incidence was 2.38 per 100 person years (py), and HCV incidence was 26.8 per 100 py. During the second follow-up period, HIV-1 incidence was 6.86 per 100 py, and HCV incidence was 28.9 per 100 py. After controlling for age and other factors, HCV seropositivity, history of sexually transmitted diseases, and sharing needles were independently associated with HIV-1 infection. These data suggest that HIV-1 incidence was rising over time in Pingxiang City, Guangxi Province. The high incidence of HCV heightens the importance of enhanced prevention programs to reduce injection and needle sharing among heroin users.     

Differential diagnosis of monoclonal gammopathies

Several disorders are associated with a monoclonal immunoglobulin detected by serum or urine electrophoresis, the most common being a monoclonal gammopathy of undetermined significance, multiple myeloma, Waldenstrom's macroglobulinemia, and amyloidosis. The clinical features of these conditions, as well as other similar entities, are described in this review. The objective is to demonstrate the importance of electrophoretic studies in the differential diagnosis of plasma cell dyscrasias and in guiding the decision for rational therapies.     

Optimization of selective hyperthermia

Selective hyperthermia can be a feasible treatment modality for deep tissue abnormalities. It is accomplished by using a laser or ultrasound noninvasively to transfer energy to a desired target causing tissue damage. This process has two potential benefits to medical professionals: simplicity of procedure and safety to patient. However, optimizing these selective interactions is difficult due to the number of variables. We propose an optimization coefficient relating the dynamic and geometric parameters of selective hyperthermia, and proceed to measure it in an experimental setup consisting of a near-infrared laser and laser-absorbing dye. To simulate tissue, gelatin phantoms are created using a combination of water, intralipid, and gelatin. Our experiments use a 1.00-cm-diam spherical phantom that is homogeneously enhanced with an indocyanine green (ICG) solution and placed inside a nontarget phantom and irradiated by an 805-nm diode laser. Temperature measurements taken at different locations are analyzed so optimization coefficients can be calculated for different parameters. This optimization coefficient compares the difference in temperatures from inside and outside the target. Analysis of the values after thermal equilibrium provides information about the best parameter selection. Our findings indicate that the optimal ICG concentration and power combination for our tested parameters are 0.083% and 0.97 W, respectively. Based on our analysis, optimization can be obtained by using this coefficient to compare the selectivity of several parameter combinations.     

Proteolysis-independent regulation of PI3K by Cbl-b-mediated ubiquitination in T cells

Cbl-b, a ring-type E3 ubiquitin protein ligase, is implicated in setting the threshold of T lymphocyte activation. The p85 regulatory subunit of phosphatidylinositol 3 kinase (PI3K) was identified as a substrate for Cbl-b. We have shown that Cbl-b negatively regulated p85 in a proteolysis-independent manner. Cbl-b is involved in the recruitment of p85 to CD28 and T cell antigen receptor zeta through its E3 ubiquitin ligase activity. The enhanced activation of Cbl-b(-/-) T cells was suppressed by the inhibition of PI3K. The results suggest a proteolysis-independent function for Cbl-b in the modification of protein recruitment.     

High prevalence of GB virus C/hepatitis G virus in Kinshasa, Democratic Republic of Congo: a phylogenetic analysis

A prevalence of 10.3% of GB virus C (GBV-C)/hepatitis G virus (HGV) carriers was found in 97 pregnant women from Kinshasa, Congo (formerly Zaire), while prevalences of 1%, 4.1%, and 0% were found for hepatitis C virus, human immunodeficiency virus, and human T-lymphotropic virus respectively. Phylogenetic analysis of the ten GBV-C/HGV positives based on the 5' non-coding region using three different methods identified consistently three GBV-C/HGV genotypes. Four main clades were found within the type 1 sequences. All the Congolese isolates are GBV-C/HGV type 1 in two different clades. The clustering of seven Congolese isolates was inconsistent in different methods. Further likelihood-mapping analysis showed a well-resolved phylogeny, confirming the clustering of the seven Congolese isolates with a Belgian strain representing a new clade in the GBV-C/HGV type 1 sequences.     

慢性乙肝患者杀伤性免疫细胞功能的研究

通过对４４例病毒性肝炎患者Ｔ细胞亚群，ＮＫ细胞活性与ＬＡＫ细胞活性的观察，探讨了在慢性乙型肝炎病毒复制与非复制状态下的杀伤性细胞活性。结果表明：在乙肝病毒的高复制状态下，ＣＤ８＾＋细胞数增加，ＣＤ４＾＋／ＣＤ８＾＋比例显著下降；ＮＫ细胞活性与ＬＡＫ细胞活性也明显低下，且在ＨＢｅＡｇ与ＨＢＶＤＮＡ阳性组中，ＮＫ活性与ＬＡＫ活性的改变与ＨＢｅＡｇ的Ｐ／Ｎ值变化呈显著负相关，而ＮＫ活性与ＬＡＫ活性变化则     

从EST克隆中筛选肝癌内高表达的基因片段

应用Ｎｏｒｔｈｅｒｎ杂交技术，从表达序列标记（Ｅｘｐｒｅｓｓｅｄｓｅｑｕｅｎｃｅｔａｇ，ＥＳＴ）克隆中筛选出一个在肝癌组织内高表达，而在相应癌旁肝及正常肝组织内低表达或不表达的基因片段。ＤＮＡ序列测定表明，该基因片段为一未知新基因的部分序列。此基因片段可作为探针，进一步筛选ｃＤＮＡ文库，以得到新的癌基因的候选基因。     

69例小儿遗传病分析

本文报告小儿遗传咨询门诊及新生儿科确诊的遗传病:染色体病23例,其中核型异常16例,结构异常7例;常染色体显性遗传病11例,常染色体隐性遗传病28例;性连锁遗传病6例;血红蛋白异常1例,共计69例。常染色体遗传病占55％,染色体异常综合征占33％。常染色体病种类繁多,尽管发病率不高,但危害很大,给诊断带来困难。     

Association of DAAO with schizophrenia in the Chinese population

Recently, the gene called DAAO was reported to be associated with schizophrenia in the French Canadian populations. Here, we report a result obtained in the study of our large collection of 547 schizophrenia cases and 536 controls in the Chinese population. Six single-nucleotide polymorphisms (SNPs) were genotyped at and around the DAAO locus, covering a 10-kb region entirely encompassing the complementary DNA sequences of DAAO. We found statistically significant differences in allele distributions on one marker: SNP rs3741775 (P = 0.0000001). In the haplotype analysis based on the information of linkage-disequilibrium block across this gene locus, we demonstrated a highly significant association between schizophrenia and a DAAO haplotype (P = 2.0173 x 10(-21)), which therefore provides an independent statistical support for association of the DAAO gene with schizophrenia and indicates that the DAAO gene may play a significant role in the etiology of schizophrenia in the Han Chinese.     

Histamine content, synthesis and degradation in nasal mucosa and lung of guinea-pigs treated with toluene diisocyanate (TDI)

We have reported the presence of a histamine synthesizing enzyme, histidine decarboxylase (HDC), and histamine degrading enzymes, histamine N-methyltransferase (HMT) and histaminase (diamine oxidase, DAO) in human nasal mucosa and the histamine content of the mucosa. In this study, we demonstrate the influences of the toluene diisocyanate (TDI) treatment on the histamine content and these enzyme activities in guinea-pigs as an animal model of respiratory hypersensitivity. Application of TDI to the nasal vestibuli induced intense nasal allergy-like and mild asthma-like responses in TDI-sensitized guinea pigs. Increases in the histamine content and HDC and HMT activities were observed in the nasal mueosa and lung of TDI-sensitized guinea pigs. No apparent changes in the histaminase activities were observed in either the nasal mucosa or the lung. These data suggest that the turnover rate of histamine is increased in the nasal mucosa and the lung of guinea pigs with respiratory hypersensitivity.