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Chinese Origin (chinese + origin)
Selected AbstractsIdentification of forty-five novel and twenty-three known NF1 mutations in Chinese patients with neurofibromatosis type 1,,HUMAN MUTATION, Issue 8 2006Ming-Jen Lee Abstract Neurofibromatosis type 1 (NF1), characterized by skin neurofibromas and an excess of café-au-lait spots, is due to mutations in the neurofibromin (NF1) gene. Identifying the genetic defect in individuals with the disease represents a significant challenge because the gene is extremely large with a high incidence of sporadic mutations across the entire gene ranging from single nucleotide substitutes to large deletions. In the present study, we have used a combination of techniques (heteroduplex analysis, sequencing, loss of heterozygosity and quantification of gene dosage) to define the genetic defect in 68 individuals from a cohort of 107 NF1 Taiwanese patients of Chinese origin. Fifty-eight were initially identified using heteroduplex analytical techniques and confirmed by sequence analysis. A further five were identified by direct sequence analysis alone. The reminders were shown to carry large deletions in the NF1 gene by demonstrating loss of heterozygosity that was confirmed by gene dosage measurements using quantitative-PCR techniques. Mis-sense, non-sense, frame-shift or splice-site mutations were identified across the entire gene of which the majority (45/68) were novel in nature. The detection rate with the various analytical techniques and the types of mutation detected are consistent with published data involving both individuals and large cohort studies from other ethnic backgrounds. © 2006 Wiley-Liss, Inc. [source] Rhesus macaque antibody molecules: sequences and heterogeneity of alpha and gamma constant regionsIMMUNOLOGY, Issue 1 2004Franco Scinicariello Summary Rhesus macaques (Macaca mulatta) are extensively used in vaccine development. Macaques infected with simian immunodeficiency viruses (SIV) or simian-human immunodeficiency viruses (SHIV) are the best animal model currently available for acquired-immune-deficiency-syndrome-related studies. Recent results emphasize the importance of antibody responses in controlling HIV and SIV infection. Despite the increasing attention placed on humoral immunity in these models, very limited information is available on rhesus macaque antibody molecules. Therefore, we sequenced, cloned and characterized immunoglobulin gamma (IGHG) and alpha (IGHA) chain constant region genes from rhesus macaques of Indian and Chinese origin. Although it is currently thought that rhesus macaques express three IgG subclasses, we identified four IGHG genes, which were designated IGHG1, IGHG2, IGHG3 and IGHG4 on the basis of sequence similarities with the four human genes encoding the IgG1, IgG2, IgG3 and IgG4 subclasses. The four genes were expressed at least at the messenger RNA level, as demonstrated by real-time reverse transcription polymerase chain reaction (RT-PCR). The level of intraspecies heterogeneity was very high for IGHA genes, whereas IGHG genes were remarkably similar in all animals examined. However, single amino acid substitutions were present in IGHG2 and IGHG4 genes, indicating the presence of IgG polymorphism possibly resulting in the expression of different allotypes. Two IgA alleles were identified in several animals and RT-PCR showed that both alleles may be expressed. Presence of immunoglobulin gene polymorphism appears to reflect the unusually high levels of intraspecies heterogeneity already demonstrated for major histocompatibility complex genes in this non-human primate species. [source] A study on interaspecific biodiversity of eight groups of silkworm (Bombyx mori) by biochemical markersINSECT SCIENCE, Issue 2 2005KAYVAN ETEBARI Abstract The recognition of biodiversity in different races and lines of silkworm (Bombyx mori) is very useful for breeding programs and production of high efficiency hybrids. In this study eight groups of silkworm were selected including 103, 107, Xihang 1 and 2 of Japanese origin and 104, 110, Koming 1 and 2 of Chinese origin. The activity levels of three enzymes including alkaline phosphatase, alanine aminotransferase and aspartate aminotransferase in haemolymph of fifth instar larva were measured. Moreover, the quantitative amount of total protein, cholesterol and glucose of haemolymph was evaluated. The data reveal that the activity level of measured macromolecules except for alkaline phosphatase were significantly different in all the groups. Hierarchical agglomerative clustering under UPGMA model separated line 104 from other groups. Two groups of Koming 1 and Xihang 1 had the most intergroup similarities. [source] Primary biliary cirrhosis in Singapore: Evaluation of demography, prognostic factors and natural course in a multi-ethnic populationJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 4 2008Reuben-Km Wong Abstract Background and Aim:, Primary biliary cirrhosis (PBC) is infrequent in Asians. Among Asian patients with PBC, information on natural course is scarce. The aim of this study was to study the clinical course and prognosticators among Asians with PBC. Methods:, During 1990,2005, patients diagnosed with PBC at the National University Hospital, Singapore, constituted the retrospective cohort. Their demographic characteristics were evaluated. To evaluate the prognostic factors and natural course, two outcome measures were assessed: hepatic decompensation and death or liver transplant. Multivariate analysis was undertaken to identify factors associated with hepatic decompensation and terminal event (death or liver transplantation). Results:, Thirty-four PBC patients aged 56.8 ± 1.8 years (mean ± SEM) of whom 32 (94%) were women were included. Thirty-two (94%) of them were of Chinese origin. At presentation, 18 (53%) were symptomatic in the form of jaundice (n = 9, 26.5%), pruritus (n = 6, 17.6%) and fatigue (n = 5, 14.7%). During 4.80 ± 0.7 (range 0.02,15.03) years follow up, 6/16 (37.5%) asymptomatic patients developed symptoms. After 5 years, 17.6% (n = 6) and 8.8% (n = 3) had hepatic decompensation and terminal event, respectively. Sicca syndrome was present in 26% (n = 9) of patients. Multivariate analysis revealed that serum bilirubin level at presentation was the sole determinant of decompensation. Rate of change of laboratory indices did not predict either event. Conclusion:, In Singapore, Chinese women constitute most of the PBC patients. Elevated serum bilirubin level at presentation was the sole predictive marker associated with dismal outcome. [source] Alopecia areata in a rhesus monkey (Macaca mulatta)JOURNAL OF MEDICAL PRIMATOLOGY, Issue 3 2007B. Beardi Abstract Background, A 14-year-old female rhesus monkey (Macaca mulatta) of Chinese origin has been suffering from alopecia universalis since childhood. Methods, Recently, the health status of the animal was recorded comprehensively by detailed clinical examination including hematology and serology supplemented by histological and immunohistochemical investigations of skin biopsies and molecular biological techniques to clarify the causes of the persistent hair loss. Results and conclusions, The hairless gene (hr) nonsense mutation was ruled out by polymerase chain reaction and by sequencing of the corresponding gene. Histological examinations revealed a prominent chronic lymphocytic perifolliculitis and folliculitis affecting anagen stage hair follicles as well as miniaturized hair follicles. Immunohistochemistry using the antibodies CD3, CD20 and CD4 confirmed the diagnosis of a T-cell-mediated autoimmune disease resembling alopecia areata universalis in humans. [source] Longitudinal follow up of SIVmac pathogenesis in rhesus macaques of Chinese origin: emergence of B cell lymphomaJOURNAL OF MEDICAL PRIMATOLOGY, Issue 4-5 2002B. Ling Abstract: Two subspecies of rhesus (Rh) macaques, the Chinese (Ch) and Indian (Ind) subspecies were infected intravenously with 100TCID50 SIVmac239. CD4+, CD8+ T cells, plasma viral loads, depletion of intestinal lymphocytes with memory phenotype, humoral immune responses and clinical courses were monitored for 600 days. The pathogenesis of SIVmac was also compared with primary human immunodeficiency virus (HIV) infection of humans. Plasma viral loads in Ch Rh were lower in the acute and chronic phases compared with Ind Rh. SIVmac pathogenesis in Ch Rh was closer to virus loads in untreated HIV infected humans. Ch Rh had higher CD4/CD8 ratios, stronger antibody responses and interestingly, less depletion of intestinal memory CCR5+ CD4+ T lymphocytes compared with Ind Rh. One Ch Rh developed B cell origin lymphoma at 570 days post-infection, the first such report in this subspecies. Three of four Ind Rh developed AIDS within 6 months. The findings indicate that Ch Rh are more resistant to SIVmac pathogenesis compared with Ind Rh and that Ch Rh paralleled HIV-1 infections in untreated adult humans. The SIVmac infected Ch Rh subspecies are an acceptable model for HIV/AIDS. [source] Hepatitis C in ethnic minority populations in EnglandJOURNAL OF VIRAL HEPATITIS, Issue 6 2008A. G. Mann Summary., The aim of the study was to investigate the differing epidemiology of hepatitis C-related end-stage liver disease in ethnic minorities in England. We used Hospital Episode Statistics from 1997/98 to 2004/05 to directly age-standardize numbers of episodes and deaths from hepatitis C-related end-stage liver disease in ethnic groups using the white English population as standard and the age-structured population by ethnic group from the 2001 Census. We estimated the odds of having a diagnosis of end-stage liver disease amongst hepatitis C-infected individuals in each ethnic group compared with whites using logistic regression. The main outcome measures were age-standardized morbidity and mortality ratios and morbidity and mortality odds ratios. Standardized ratios (95% confidence interval) for hepatitis C-related end-stage liver disease ranged from 73 (38,140) in Chinese people to 1063 (952,1186) for those from an ,Other' ethnic group. Amongst individuals with a diagnosis of hepatitis C infection, the odds ratios (95% CI) of severe liver disease were 1.42 (1.13,1.79), 1.57 (1.36,1.81), 2.44 (1.85,3.22), 1.73 (1.36,2.19) and 1.83 (1.08,3.10) comparing individuals of Black African, Pakistani, Bangladeshi, Indian and Chinese origin with whites, respectively. Ethnic minority populations in England are more likely than whites to experience an admission or to die from severe liver disease as a result of hepatitis C infection. Ethnic minority populations may have a higher prevalence of hepatitis C or they may experience a poorer prognosis because of differential access to health services, longer duration of infection or the prevalence of co-morbidities. [source] Rhesus monkey model for Leishmania major transmitted by Phlebotomus papatasi sandfly bitesMEDICAL AND VETERINARY ENTOMOLOGY, Issue 1 2001R. J. Probst Summary Leishmaniasis research needs a near-human model for investigations of natural infection processes, immunological responses and evaluation of treatments. Therefore, we developed a reproducible system using Leishmania major Yakimoff & Schokhor (Trypanosomatidae: Kinetoplastida), the cause of Old World zoonotic cutaneous leishmaniasis (ZCL), transmitted to rhesus monkeys Macaca mulatta (Zimmerman) (Primates: Cercopithecidae) by sandfly bites of experimentally infected Phlebotomus papatasi (Scopoli) (Diptera: Psychodidae). Eight monkeys of presumed Indian origin (Leishmania naïve) were exposed to bites of female sandflies that had been infected with L. major by membrane-feeding on human blood seeded with amastigotes isolated from hamster footpad lesions. Infection rates of membrane-fed sandflies averaged >,85% seven days after the infective feed, with uniformly high numbers of promastigotes in the stomodaeal valve region of the sandfly gut. Nodules and ulcerating dermal lesions developed on 7/8 monkeys 2,4 weeks post-bite and persisted for 3,7 months. Monkeys also developed satellite lesions beyond the area of sandfly bites on the head, but not on the chest. Three re-challenged monkeys developed lesions that healed faster than lesions from their primary challenges. After infection, monkeys developed delayed type hypersensitivity (DTH) responses to a panel of Leishmania skin test antigens (LSTA) and, when tested by ELISA and IFA, showed significant post-infection antibody titres which typically rose for ,170 days and then gradually receded during the next 100 days following the first challenge. After the second challenge, antibody titres spiked higher within ,50 days and receded more rapidly. In contrast, four rhesus macaques of Chinese origin developed no lesions following infected sandfly bites, although they raised antibodies and LSTA reactions, indicating subclinical infection. [source] Genetic characterization of rhesus macaques (Macaca mulatta) in NepalAMERICAN JOURNAL OF PRIMATOLOGY, Issue 5 2006Randall C. Kyes Abstract Indian-origin rhesus macaques (Macaca mulatta) have long served as an animal model for the study of human disease and behavior. Given the current shortage of Indian-origin rhesus, many researchers have turned to rhesus macaques from China as a substitute. However, a number of studies have identified marked genetic differences between the Chinese and Indian animals. We investigated the genetic characteristics of a third rhesus population, the rhesus macaques of Nepal. Twenty-one rhesus macaques at the Swoyambhu Temple in Kathmandu, Nepal, were compared with more than 300 Indian- and Chinese-origin rhesus macaques. The sequence analyses of two mitochondrial DNA (mtDNA) loci, from the HVS I and 12,S rRNA regions, showed that the Nepali animals were more similar to Indian-origin than to Chinese-origin animals. The distribution of alleles at 24 short tandem repeat (STR) loci distributed across 17 chromosomes also showed greater similarity between the Nepali and Indian-origin animals. Finally, an analysis of seven major histocompatibility complex (MHC) alleles showed that the Nepali animals expressed Class I alleles that are common to Indian-origin animals, including Mamu-A*01. All of these analyses also revealed a low level of genetic diversity within this Nepali rhesus sample. We conclude that the rhesus macaques of Nepal more closely resemble rhesus macaques of Indian origin than those of Chinese origin. As such, the Nepali rhesus may offer an additional resource option for researchers who wish to maintain research protocols with animals that possess key genetic features characteristic of Indian-origin rhesus macaques. Am. J. Primatol. 68:1,11, 2006. © 2005 Wiley-Liss, Inc. [source] | |||||||||||||