Detection of virus-like particles in the coremia of Penicillium claviforme.

A double-stranded ribonucleic acid (dsRNA) was isolated from coremial extracts of wild type P. claviforme, by methylated-albumin kieselguhr chromatography. Differential centrifugations of the coremial extracts from WT and Sh mutant strains yielded two classes of virus-like particles (VLP), of dimensions 25-30 nm, and 50-70 nm. The possible ecological significance of fungal viruses is discussed.     

Location and the primary structure around the disulfide bonds in cholera toxin.

The sequence of the four tryptic peptides containing cysteine from cholera toxin has been determined. The cysteine residue in peptide A₂, forms a disulfide bridge with the cysteine in the A₁ chain located near the NH₂-terminus. The region around the latter cysteine residue is characterized by a high content of proline. One of the cysteine residues that form the intrachain disulfide bond in subunit B has been located at position 9 in this subunit.     

The specificity of the synthetic reaction of two yeast alpha-glucosidases.

The specificity of the hydrolytic reaction has been compared to that of the synthetic reaction for maltase and isomaltase (alpha-methyl-D-glucosidase) from Saccharomyces oviformis. Maltase which hydrolyzes the alpha-1,4-disaccharide, maltose, and the alpha-1,6-disaccharide, isomaltose, catalyzes the formation of both maltose and isomaltose from free glucose. Isomaltase, which hydrolyzes isomaltose but not maltose, catalyzes the formation only of isomaltose from glucose. Both enzymes hydrolyze p-nitrophenyl-alpha-D-glucoside releasing the alpha-anomer of glucose. The enzymes utilize the alpha-anomer but not the beta-anomer for the synthesis of the disaccharides. These results are consistent with the double displacement mechanism for glycosidases and with the proposal that the glucosyl-enzyme complex is an intermediate in the reaction. The competitive inhibition by D-glucose is independent of its anomeric form for both enzymes.     

Cost-effectiveness evaluation of different control strategies for Clonorchis sinensis infection in a high endemic area of China: A modelling study

Clonorchiasis is an important food-borne parasitic disease caused by Clonorchis sinensis infection. The evaluation of long-term cost-effectiveness of control strategies is important for disease control and prevention. The present study aimed to assess the cost-effectiveness of the three recommended strategies (i.e., WHO, Chinese and Guangdong strategies) and different combinations of commonly used measures (i.e., preventive chemotherapy, information, education, and communication (IEC) and environmental improvement) on clonorchiasis. The study area, Fusha town in Guangdong Province, was a typical high endemic area in China. The analysis was based on a multi-group transmission model of C. sinensis infection. We set the intervention duration for 10 years and post-intervention period for 50 years. The corresponding costs and DALYs were estimated. Strategies with incremental cost-effectiveness ratios (ICERs) less than 1/5 of the willingness-to-pay threshold were identified as highly cost-effective strategies. The optimal control strategy was obtained using the next best comparator method. The ICERs of Guangdong strategy were $172 (95% CI: $143-$230) US for praziquantel and $106 (95% CI: $85-$143) US for albendazole, suggesting the highest cost-effectiveness among the three recommended strategies. For praziquantel, 470 sets of control strategies were identified as highly cost-effective strategies for achieving infection control (prevalence<5%). The optimal strategy consisted of chemotherapy targeted on at-risk population, IEC and environmental improvement, with coverages all being 100%, and with the ICER of $202 (95% CI: $168-$271) US. The results for transmission control (prevalence<1%) and albendazole were obtained with the same procedures. The findings may help to develop control policies for C. sinensis infection in high endemic areas. Moreover, the method adopted is applicable for assessment of optimal strategies in other endemic areas.     

Association between cytokines and methylation of SOCS-1 in serum of patients with ankylosing spondylitis

In this study, we aim to determine the relationship between methylation level of an inflammatory-related gene, SOCS-1 in serum samples of patients with ankylosing spondylitis (AS) and their degree of inflammation as well as serum cytokine level. Quantitative real time methylation specific PCR was performed to examine the promoter methylation of SOCS-1 in serum samples of 43 HLA-B27+ AS patients and 6 B27+ healthy controls. Degree of inflammation was accessed by spondylopathy, sacroiliitis as well as acute phase reactant, erythrocyte sedimentation rate and C-reactive protein (CRP). Serum IL-6 and TNF-α level was determined by ELISA assay. SOCS-1 methylation can only be found in serums samples from patients but not normal control. Methylation of SOCS-1 significantly associated with severity of patient’s spondylopathy (P < 0.005), sacroiliitis (P < 0.005) and acute phase reactant CRP (P = 0.0278). AS patients also exhibited higher serum IL-6 (P < 0.001) and TNF-α level (P < 0.001). Importantly, patients with high serum IL-6 or TNF-α level demonstrated a significantly higher SOCS-1 methylation (P < 0.001). In conclusion, this proof-of-principle study suggested that methylation of SOCS-1 can be detected in serum of HLA-B27+ AS patients but not in B27+ controls. The pathogenic potential of SOCS-1 methylation in AS deserves further investigation.     

Novel variant of p230 trans-Golgi network protein identified by serum from Sjögren's syndrome patient

Trans-Golgi network (TGN) protein p230 is a peripheral membrane protein associated with the cytoplasmic face of the TGN. TGNp230 is an extensively coiled-coil protein with flexible amino- and carboxyl-terminal ends, associates with non-clathrin-coated vesicles arising from the TGN, and is implicated in vesicle biogenesis. Here we used an autoimmune serum from a patient with S ogren's syndrome to clone partial cDNAs from a human hepatoma HepG2 expression library. The partial cDNAs encoded a novel amino-terminal splice variant of TGNp230. Specific reactivity of the autoimmune serum for p230 is supported by immunofluorescene staining of the Golgi apparatus, immunoblotting of a > 200-kDa HeLa cell protein, and reactivity with a bacterially expressed GST-p230 fusion protein. The alternative splicing occurs within the first proline-rich domain of p230. It comprises a deletion of 30 bp followed immediately by an additional 66 bp absent in the published sequence. RT-PCR analysis indicated that the splicing occurs independently of previously reported carboxyl-terminal splicing, and that this novel splice variant is more frequent than the previously reported p230. The novel splice variant of p230 is also located at the TGN. We propose that p230 splice variants may be implicated in selection of cargo molecules for vesicles arising from the TGN.     

中国丙型肝炎病毒基因型研究新进展

为了进一步了解中国丙型肝炎病毒基因型感染状态 ,我们建立了 5′ ＮＣＲＡＢＣ程序酶切分型法 :首先采用ＲＴＰＣＲ技术 5′ ＮＣＲ扩增ＨＣＶＲＮＡ阳性样品中的ｃＤＮＡ ,然后按照ＡＢＣ程序进行分型 ,Ａ应用ＢＨＨ(ＢｓｒＢⅠ ,ＨａｅⅡ ,ＨｉｎｆⅠ )复合内切酶消化 5′ ＮＣＲｃＤＮＡ ,Ｂ应用ＢｓｔＵⅠ消化 ,Ｃ应用ＨａｅⅢ消化 ,电泳检测片段大小。应用该方法对临床采集的ＨＣＶＲＮＡ阳性血清进行分型 ,在国内首次发...     

DHPLC检测胃癌微卫星不稳定性

为探讨一种快速、简便、可靠的胃癌微卫星不稳定性（MSI）检测方法,变性聚丙烯酰胺凝胶电泳-银染法检测28例胃癌12个微卫星位点(D1S548、D1S552、D5S346、TP53、IGFIIR(G)8、IGFIIR(CT)5、TGFßRII(GT)3、TGFßRII(A)10、hMSH3(A)8、hMSH6(G)8、BAX(G)8和Bat26）,DHPLC柱温50℃检测Bat26位点。凝胶电泳发现MSI-H 2例（7.14%）,MSI-L胃癌15例（53.6%）,Bat26+2例均为MSI-H,Bat26改变和MSI-H表型一致（P<0.01,Fisher’s确切概率法）。DHPLC亦证实2例Bat26+胃癌,结果和凝胶电泳完全一致。结果表明,DHPLC检测Bat26位点是研究胃癌MSI-H的较好方法,有一定的临床应用价值。Abstact: To establish a fast, simple and solid method of studying microsatellite instability (MSI) in gastric cancer, a panel of 12 microsatellite sites,D1S548, D1S552, D5S346, TP53, IGFIIR(G)8, IGFIIR(CT)5, TGFßRII(GT)3, TGFßRII(A)10, hMSH3(A)8, hMSH6(G)8, BAX(G)8 and Bat26, were detected by denatured polyacrymide gel electrophoresis-silver stain in 28 gastric cancers. Bat26 was also analyzed by denatured high performance liquid chromatograph (DHPLC) at 50℃ in the DNASep Cartridge. Two MSI-H (7.14%) and 15 MSI-L cancers (53.6%) were identified in 28 gastric cancers. Bat26 was positive only in 2 MSI-H cancers. The alterations of Bat26 and MSI-H status were coincident (P<0.01). The two Bat26+ cancers were also confirmed by DHPLC. Results obtained from DHPLC and gel electrophoresis were completely consistent. Thus, DHPLC analysis of Bat26 site may be a favorable method of detecting MSI-H status in gastric cancer, and be of clinical importance.