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41.
42.
We investigated effects of sleep on pain-related somatosensory evoked potentials (SEP) following painful electrical stimulation of the left index finger. The biggest advantage of this method is that signals ascending through both A-beta fibers relating to touch and A-delta fibers relating to pain can be recorded simultaneously. While the subject was awake, non-painful stimulation evoked early- and middle latency components, N20, P30 and N60, at the C4 electrode, and painful stimulation evoked not only early- and middle latency components at the C4 but also later pain-specific components, N130 and P240, at the Cz electrode. During sleep, N20 and P30 did not show a significant change in amplitude, N60 showed a slight but significant amplitude reduction, and N130 and P240 significantly decreased in amplitude or disappeared, as compared with those while awake. Therefore, we speculate on the mechanisms generating each component as follows; (1) N20 and P30 are the primary components generated in SI ascending through A-beta fibers. (2) N60 is the secondary component generated in SI involving cognitive function to some degree. (3) N130-P240 are the pain-specific components ascending through A-delta fibers, and closely related to cognitive function, because they were much affected by consciousness, different from the components ascending through A-beta fibers. 相似文献
43.
Survey of CAG/CTG repeats in human cDNAs representing new genes: candidates for inherited neurological disorders 总被引:3,自引:2,他引:3
Neri C; Albanese V; Lebre AS; Holbert S; Saada C; Bougueleret L; Meier-Ewert S; Le Gall I; Millasseau P; Bui H; Giudicelli C; Massart C; Guillou S; Gervy P; Poullier E; Rigault P; Weissenbach J; Lennon G; Chumakov I; Dausset J; Lehrach H; Cohen D; Cann HM 《Human molecular genetics》1996,5(7):1001-1009
44.
Kenji Abe Eriko Hayakawa Andrei V Sminov Anna L Rossina Xin Ding Tran T-T Huy Tetsutaro Sata Vasily F Uchaikin 《Journal of clinical virology》2004,30(1):57-61
BACKGROUND: It is known that the prevalence of HBV and HCV infections vary according to geographical areas. However, in Russia, an adequate level of information on the molecular epidemiology of hepatitis viruses has not been available so far. OBJECTIVES: To investigate the characterization of various hepatitis viruses in Russia, we conducted molecular-based epidemiological survey of hepatitis viruses including hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis D virus (HDV) and hepatitis E virus (HEV) among children in Moscow, Russia. STUDY DESIGN: The study population of 374 subjects (ranging in age from 1 to 14 years old) consisted of 195 patients with liver diseases and 179 patients without liver diseases. Viral DNA/RNA was determined by nested PCR. Genotyping of HBV and HCV were examined by PCR using type-specific primers. Anti-HEV antibody was assayed by ELISA. RESULTS: The infection rate of each virus among patients with liver diseases including acute hepatitis, chronic hepatitis or cirrhosis was 65.6% for HBV and 15.9% for HCV. In contrast, among non-liver disease patients, the infection rates were 14.4% for HBV and 0.6% for HCV, respectively. The most common viral genotypes were type D (85%) of HBV and type 1b (79.3%) of HCV. HDV RNA was detected in 7 of 149 (4.7%) HBV DNA-positive children tested. Moreover, testing for HEV among 341 subjects resulted in the detection of anti-HEV IgG in 62 cases (18.2%). CONCLUSIONS: Our results suggest that HBV infection is widespread in Moscow and have led to a high incidence of acute and chronic liver diseases among children in this region. 相似文献
45.
46.
Lai PS Takeshima Y Adachi K Van Tran K Nguyen HT Low PS Matsuo M 《Journal of human genetics》2002,47(10):0552-0555
The frequency and distribution of deletions of 19 deletion-prone exons clustered in two hot spots in the proximal and central
regions of the dystrophin gene were compared in three populations from Singaporean, Japan, and Vietnam. DNA samples obtained
from 105 Singaporean, 86 Japanese, and 34 Vietnamese Duchenne muscular dystrophy patients were examined by polymerase chain
reaction amplification. Deletions of the examined exons were found in 51.2% of Japanese patients but in 40.0% or less of the
Singaporeans and Vietnamese. About two thirds of the deletions were localized in the central region and the remaining deletions
were clustered at the proximal region. The most commonly deleted exons at the central deletion hot spot were exon 50 in the
Singaporean, exons 49 and 50 in the Japanese, and exon 51 in the Vietnamese population. At the proximal deletion hot spot,
the most commonly deleted exons were exons 6 and 8 in the Singaporeans, exons 12 and 17 in the Japanese, and exons 8 and 12
in the Vietnamese. Two cases each from Singapore and Japan had large-scale gross mutations spanning both deletion hot spots.
Our results suggest that, although the presence and frequency of the two deletion hot spots may be similar in the three Asian
populations analyzed, the distribution and frequency of deletions among the different exons can vary as a result of population-specific
intronic sequences that predispose individuals to preferential deletion breakpoints.
Received: May 20, 2002 / Accepted: July 1, 2002 相似文献
47.
Analogues of baclofen, phaclofen and saclofen, incorporating a sulfur atom within the methylene chain, have been tested against responses induced by baclofen for activity at gamma-aminobutyric acid-B (GABAB) receptor sites, using a number of preparations including the guinea-pig isolated ileum and vas deferens, rat brain cortical slices and displacement of (-)-[3H]baclofen in rat cerebellar membranes. Results indicate that 2-([2-amino-1-(4-chlorophenyl)ethyl]thio)ethanephosphonic acid 2d is the most active of the new compounds. 2d is some 2-5 times weaker than phaclofen as a GABAB antagonist and approximately half as potent as phaclofen as an inhibitor of GABAB binding. 相似文献
48.
de Jong MD Bach VC Phan TQ Vo MH Tran TT Nguyen BH Beld M Le TP Truong HK Nguyen VV Tran TH Do QH Farrar J 《The New England journal of medicine》2005,352(7):686-691
In southern Vietnam, a four-year-old boy presented with severe diarrhea, followed by seizures, coma, and death. The cerebrospinal fluid contained 1 white cell per cubic millimeter, normal glucose levels, and increased levels of protein (0.81 g per liter). The diagnosis of avian influenza A (H5N1) was established by isolation of the virus from cerebrospinal fluid, fecal, throat, and serum specimens. The patient's nine-year-old sister had died from a similar syndrome two weeks earlier. In both siblings, the clinical diagnosis was acute encephalitis. Neither patient had respiratory symptoms at presentation. These cases suggest that the spectrum of influenza H5N1 is wider than previously thought. 相似文献
49.
The serious result of hepatitis B (HBV) virus infection is development of hepatocellular carcinoma (HCC). However, the reason of development of HCC in HBV infected patients is still unclear. Recently, the suppression of cell apoptosis is found to relate with the development of cell carcinogenesis, therefore, the expression of apoptosis inhibitor in the virus related cancer line such as hepatoma cell line HepG2.215 was investigated. There are at least six Human apoptosis inhibitors (IAP) have been identified now. They are cIAP1, cIAP2, XIAP, NAPI, survivin and pIAP. Using gene-assay technology, we have recently compared the expression of IAPs in the HepG2.215 cells that persistently expresses Hepatitis B virus by integrated HBV genome with its parent cell line HepG2. The results suggest that there was obviously increase of cIAP2 and cIAP1 in the HepG2.215 cells versus HepG2 cells. Those observations imply a possibility of long time HBV infection could induce the over-expressing apoptosis inhibitors, furthermore, causing the liver cancer. The high expression of cIAP1 and cIAP2 in HBV expressing cells was confirmed by RT-PCR and Northern blot analysis. However, we did not find the change of NIAP and suvivin in HepG2.215 cells. In contrast, the expression of XIAP was down in the HepG2.215 cells comparing with HepG2 cells. How HBV triggers the over-expression of apoptosis inhibitor is unclear. Transient transfection of HepG2 cells with the plasmids expressing different HBV proteins such as S, M, L, X and core proteins did not give a decisive conclusion. Further study is going on now. 相似文献
50.
Adjuvant-dependent modulation of Th1 and Th2 responses to immunization with beta-amyloid 总被引:6,自引:0,他引:6
Cribbs DH Ghochikyan A Vasilevko V Tran M Petrushina I Sadzikava N Babikyan D Kesslak P Kieber-Emmons T Cotman CW Agadjanyan MG 《International immunology》2003,15(4):505-514
The role of adjuvant on the T(h)1 and T(h)2 immune responses to Abeta-immunotherapy (Abeta(42 )peptide) was examined in wild-type mice. Fine epitope analysis with overlapping oligomers of the Abeta(42) sequence identified the 1-15 region as a dominant B cell epitope. The 6-20 peptide was recognized only weakly by antisera from mice administrated with Abeta(42) peptide formulated in complete Freund's adjuvant (CFA), alum or TiterMax Gold (TMG). However, mice immunized with Abeta(42) mixed with QS21 induced a significant antibody response to the 6-20 peptide. The only T cell epitope found was within the 6-28 sequence of Abeta(42). QS21 and CFA induced the strongest humoral response to Abeta, alum was intermediate, and TMG the weakest adjuvant. Analysis of antibody isotypes specific for Abeta indicates that alum induces primarily T(h)2-type immune response, whereas TMG, CFA and QS21 shift the immune responses toward a T(h)1 phenotype. Stimulation of splenocytes from Abeta-immunized mice with Abeta(40) peptide induced strikingly different cytokine expression profiles. QS21 and CFA induced significant IFN-gamma, IL-4 and tumor necrosis factor-alpha expression, whereas alum induced primarily IL-4 production. As T(h)1-type immune responses have been implicated in many autoimmune disorders, whereas T(h)2-type responses have been shown to inhibit autoimmune disease, the choice of adjuvant may be critical for the design of a safe and effective immunotherapy for Alzheimer's disease. 相似文献