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An integrated human-mouse positional candidate approach was used to identify the gene responsible for the phenotypes observed in a mouse model of Niemann-Pick type C (NP-C) disease. The predicted murine NPC1 protein has sequence homology to the putative transmembrane domains of the Hedgehog signaling molecule Patched, to the cholesterol-sensing regions of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase and SREBP cleavage-activating protein (SCAP), and to the NPC1 orthologs identified in human, the nematode Caenorhabditis elegans, and the yeast Saccharomyces cerevisiae. The mouse model may provide an important resource for studying the role of NPC1 in cholesterol homeostasis and neurodegeneration and for assessing the efficacy of new drugs for NP-C disease.

Niemann-Pick disease type C (NP-C) is an autosomal recessive lipidosis linked to chromosome 18q11-12, characterized by lysosomal accumulation of unesterified cholesterol and delayed induction of cholesterol-mediated homeostatic responses. This cellular phenotype is identifiable cytologically by filipin staining and biochemically by measurement of low-density lipoprotein-derived cholesterol esterification. The mutant Chinese hamster ovary cell line (CT60), which displays the NP-C cellular phenotype, was used as the recipient for a complementation assay after somatic cell fusions with normal and NP-C murine cells suggested that this Chinese hamster ovary cell line carries an alteration(s) in the hamster homolog(s) of NP-C. To narrow rapidly the candidate interval for NP-C, three overlapping yeast artificial chromosomes (YACs) spanning the 1 centimorgan human NP-C interval were introduced stably into CT60 cells and analyzed for correction of the cellular phenotype. Only YAC 911D5 complemented the NP-C phenotype, as evidenced by cytological and biochemical analyses, whereas no complementation was obtained from the other two YACs within the interval or from a YAC derived from chromosome 7. Fluorescent in situ hybridization indicated that YAC 911D5 was integrated at a single site per CT60 genome. These data substantially narrow the NP-C critical interval and should greatly simplify the identification of the gene responsible in mouse and man. This is the first demonstration of YAC complementation as a valuable adjunct strategy for positional cloning of a human gene.

To identify candidate genes for Branchio-oto-renal (BOR) syndrome, we have made use of a set of cosmids that map to 8q13.3, which has previously been shown to be involved in this syndrome. These cosmids were used as genomic clones in the attempts to isolate corresponding cDNAs using a modified hybrid selection technique. cDNAs from the region were identified and used to search for sequence similarity in human or other species. One cDNA clone was found to have 89% sequence similarity to the bovine B22 subunit of NADH-ubiquinone oxidoreductase, a mitochondrial protein in the respiratory electron transport chain. Given the history of other mitochondrial mutations being involved in hearing loss syndromes, this gene should be considered a strong candidate for involvement in BOR.

Genetic linkage analysis has previously mapped the locus for the autosomal dominant disorder branchio-oto-renal syndrome (BOR) to the pericentric region of chromosome 8q. A YAC contig spanning the putative BOR region, from D8S543 to D8S541, was constructed and confirmed by sequence-tagged site content mapping using microsatellite markers and by DNA hybridization analysis. YACs spanning the BOR interval were used as fluorescence in situ hybridization probes on a cell line from a patient with BO and tricho-rhino-phalangeal syndrome I that involves a chromosome 8q rearrangement. In addition to the cytogenetically defined direct insertion of material from 8q13.3-q21.13 into 8q24.11, a previously unidentified deletion of just under one megabase was found in 8q13.3. These data narrowed the most likely location of the BOR gene to a region corresponding to the proximal two-thirds of YAC 869E10 between D8S543 and D8S279.

Malignant melanoma is a kind of tumor with higher malignant and lower therapeutic effect.it is demonstrated by experiment that melanoma cells have antigenicity and refer to immunology.BCG is a kind of biologic response modifier(BRM).it is able to promote physical antitumor ability.There were 42 patients with oral and maxillofacial malignant melanoma who received freezing therapy and surgery in this paper.11 cases of them added BCG immunotherapy.The result is that the median survival time of therapy plus BCG group is 4 years,and 3 years,5 years,7 years survival rate are 89%,72% and 32%,over 8 years survival rate is 18%.The median survival time of another group is 2 years,and 3 years,5 years,7 years survival rate are 55%,24% and 12%,over 8 years survival rate is 3%.There is a statistically significant difference between these two groups and BCG group has a longer survival time.This preliminary study demonstrated that BCG adjuvant therapy could decrease recurrence of metastases and increase patients survival time.

Wedge biopsies of liver from 155 patients with advanced schistosomiasis japonica were observed pathologically, and HBsAg and HBcAg in liver were tested with double bridge peroxidase-anti-peroxidase (PAP) method. 88 of 155 cases (56.8%) were found to be HBsAg and/or HBcAg (HBAg) positive in liver. Eosinophilic intranuclear inclusions were observed in the hepatocytes of 30 cases (19.4%), in which 18 (60%) were also HBAg positive in liver. These inclusions were considered to be the markers of several virus infections, such as cytomegalovirus, herpes simplex virus, etc. The patients with positive HBAg and/or inclusion in liver had significantly more severe pathological changes in liver parenchyma. The results indicate that in addition to hepatitis B, complication with other viral infections in liver, which produce eosinophilic intranuclear inclusion, may also aggravate the pathological changes in liver and may be one of the causes of portal cirrhosis in patients with advanced schistosomiasis japonica (Fig. 1). schistosomiasis japonica