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41.
A new endemic focus of human T-lymphotropic virus type I (HTL V-I) was recently reported among Mashhadi Jews, a group of immigrants from northeastern Iran to Israel. We extracted DNAs from fresh peripheral blood mononuclear cells (PBMCs) and/or gargle mouthwash from 10 HTL V-I carriers, who consisted of members of one family, and HTL V-I-associated myelopathy (HAM) and adult T-cell leukemia (ATL) patients. Long terminal repeat (LTR) regions of proviral DNAs were sequenced and analyzed phylogenetically. In a phylogenetic tree, all the Mashhadi HTL V-I isolates belonged to subtype A, one of the three subtypes of the cosmopolitan type of HTL V-I, and made a tight cluster distinct from the other isolates of subtype A from Japan, India, the Caribbean Basin, and South America. Although a few nucleotide substitutions were observed among the clones sequenced, no characteristic sequence variation was found in different disease manifestations, even in one family or different sources of DNA preparation.  相似文献   
42.
A latex agglutination assay was developed to identify Campylobacter jejuni and Campylobacter coli. We evaluated the specificity, reproducibility and utility of the assay for clinical use and the following results were obtained. 1) To prepare standardized antigen, bacterial cells must be suspended to a density of 1 to 5 McFarland unit, and heated at 121 degrees C for 10 to 30 min. 2) Bacterial cells may be suspended either in the solution provided with the kit, or in physiological saline, without affecting the results. 3) Of C. jejuni, 94 strains, 6 of C. coli, and 3 of "Campylobacter upsaliensis", all tested positive without exception. All other Campylobacter species, encompassing 13 species and 80 strains, were negative. An additional 9 species and 30 strains, of non-Campylobacter gram negative bacteria, isolated on the Campylobacter selection agar medium, also were uniformly negative. Based on these results, we conclude that bacteria testing positive with the kit can be identified as C. jejuni/coli. Interestingly, "C. upsaliensis", although isolated very rarely from the clinical specimens, also tested positive.  相似文献   
43.
Studies on functional compatibility of various Rev proteins derived from all known human and simian immunodeficiency virus subgroups have shown that this essential gene product is not always exchangeable among the viruses. In an attempt to map the region of Rev proteins responsible for the observed nonreciprocal complementation, hybrid genomic Rev expression vectors were constructed by exchanging the first and second exons ofrev genes, and were examined for their abilities to activate reporter clones by transfection. With one exception, the second coding exon ofrev gene determined the functional specificity of Rev proteins.  相似文献   
44.
Chimeric simian and human immunodeficiency viruses (SHIVs) are useful for investigating the pathogenicity of human immunodeficiency virus (HIV-1) and to develop an anti-HIV-1 vaccine. We attempted to construct SHIVs containing Env from various subtypes, because almost all SHIVs which have been reported so far have Env from HIV-1 that belongs to subtype B. Two infectious SHIVs containing Env from two strains of HIV-1, CMR304 and CMR306, which belong to subtype F and A, respectively, were newly obtained. These SHIVs essentially showed a coreceptor usage and a neutralization pattern that were similar to those of the parental HIV-1s. In macaque PBMC, SHIVcmr304 replicated with kinetics similar to that of prototypic SHIV-NM-3rN with HIV-1 NL432 Env, but SHIVcmr306 replicated poorly. Inoculation of four rhesus macaques with SHIVcmr304 resulted in an increase of plasma viral load in all the macaques, though viral RNA copies were 100-fold lower than that in the infection with NM-3rN. This SHIV containing Env from HIV-1 subtype F will be a valuable source for the analysis of HIV-1 subtype F and the evaluation of vaccine candidates as a genetically divergent challenge virus.  相似文献   
45.
BACKGROUND: Over 90% of Ewing's sarcoma/primitive neuroectodermal tumour (ES/PNET) cases have the t(11;22) chromosomal rearrangement, which is also found in other small round cell tumours, including desmoplastic small round cell tumour (DSRCT) and clear cell sarcoma (CCS). Although this rearrangement can be analysed by fluorescence in situ hybridisation (FISH) using routinely formalin fixed, paraffin wax embedded (FFPE) tissues when fresh or frozen tissues are not available, a sensitive and convenient detection method is needed for routine clinical diagnosis. AIMS: To investigate the usefulness of newly developed probes for detecting EWS rearrangement resulting from chromosomal translocations using FISH and FFPE tissue in the clinical diagnosis of ES/PNET, DSRCT, and CCS. METHODS: Sixteen ES/PNETs, six DSRCTs, and six CCSs were studied. Three poorly differentiated synovial sarcomas, three alveolar rhabdomyosarcomas, and three neuroblastomas served as negative controls. Interphase FISH analysis was performed on FFPE tissue sections with a commercially available EWSR1 (22q12) dual colour, breakapart rearrangement probe. RESULTS: One fused signal and one split signal of orange and green, demonstrating rearrangement of the EWS gene, was detected in 14 of 16 ES/PNETs, all six DRSCTs, and five of six CCSs, but not in the negative controls. CONCLUSIONS: Interphase FISH using this newly developed probe is sensitive and specific for detecting the EWS gene on FFPE tissues and is of value in the routine clinical diagnosis of ES/PNET, DSRCT, and CCS.  相似文献   
46.
To elucidate characteristic changes in the N -methyl- d -aspartate (NMDA) receptor on neurons following axotomy, subunit expressions and functional features of the NMDA receptor were examined in the dorsal motor nucleus of vagus (DMV) of rats receiving vagal axotomy at the neck. Western blotting analysis demonstrated that the expression of NR2A decreased 2–3 days after in vivo axotomy, while expression of NR1 and NR2B, NR2C and NR2D subunits did not change significantly. To examine the functional changes, patch clamp recordings in whole-cell mode were employed on the axotomized DMV neurons identified by retrograde labelling with fluorescent dye. The amplitude ratios of ifenprodil-sensitive components of NMDA response and d , l -2-amino-5-phosphovaleric acid (APV)-sensitive evoked postsynaptic current increased after axotomy. In addition, APV-sensitive postsynaptic currents exhibited a longer decay time in identified axotomized vagal motoneurons than in control neurons. No significant differences in the current density of the NMDA response and the peak amplitude of APV-sensitive synaptic currents were observed between axotomized and intact DMV neurons. In conclusion, a decrease in NR2A expression results in the appearance of functional characteristics of the NMDA receptor predominantly containing the NR2B subunit. This might lead to a long-term increase of the susceptibility of neurons to excitotoxicity.  相似文献   
47.
To monitor the presence of genotypic HIV-1 variants circulating in eastern Cameroon, blood samples from 57 HIV-1-infected individuals attending 3 local health centers in the bordering rural villages with Central African Republic (CAR) were collected and analyzed phylogenetically. Out of the 40 HIV-1 strains with positive polymerase chain reaction (PCR) profile for both gag and env-C2V3,12 (30.0%) had discordant subtype or CRF designation: 2 subtype B/A (gag/env), 1 B/CRF01, 2 B/CRF02, 1 CRF01/CRF01.A, 2 CRF11/CRF01, 1 CRF13/A, 1 CRF13/CRF01, 1 CRF13/CRF11, and 1 G/U (unclassified). Twenty-eight strains (70.0%) had concordant subtypes or CRF designation between gag and env: 27 subtype A and 1 F2. Out of the remaining 17HIV-1 strains negative for PCR with the env-C2V3 primers used, 10 (58.8%) had discordant subtype or CRF, and 7 (41.2%) had concordant one based on gag/pol/env-gp41 analysis. Altogether, a high proportion (22/57, 38.6%) of the isolates were found to be recombinant strains. In addition, an emergence of new forms of HIV-1 strains, such as subtype B/A (gag/env), B/CRF01 and B/CRF02, was identified. The epidemiologic pattern of HIV-1 in eastern Cameroon, relatively low and high prevalence of CRF02 and CRF11, respectively, was more closely related to those of CAR and Chad than that of other regions of Cameroon, where CRF02 is the most predominant HIV-1 strain. These findings strongly suggest that this part of Cameroon is a potential hotspot of HIV-1 recombination, with a likelihood of an active generation of new forms of HIV-1 variants, though epidemiologic significance of new HIV-1 forms is unknown.  相似文献   
48.
Helicobacter pylori is closely related to upper gastrointestinal diseases, and the precise evaluation of H. pylori infection is necessary for the treatment of these diseases. The aim of the present study was to establish a method for the quantitative detection of H. pylori. We applied a competitive PCR method using various amounts of synthetic DNA fragments containing the same primer-binding and a subset of the same template sequences as the target competing for primer binding and amplification in order to quantify H. pylori in gastric mucus. The results obtained by this method were compared with the results of histological examination, the rapid urease test, bacterial culture, the [13C]urea breath test, and urea and ammonia measurements in gastric juice. As the quantity of H. pylori in gastric mucus increased, the rates of positivity of histological examination, the rapid urease test, and bacterial culture increased. The quantity of H. pylori in gastric mucus was also significantly correlated with the results of the [13C]urea breath test and was negatively correlated with the urea/ammonia ratio in gastric juice. The competitive PCR method provides an objective measure of the quantity of H. pylori and makes it possible to distinguish true negatives from false negatives due to incomplete PCR and true positives from false positives due to contamination. This method is very useful for the precise evaluation of gastric H. pylori infection.  相似文献   
49.
Pathogenicity of avian nephritis virus (ANV) was studied in 7‐day‐old chicks previously infected with infectious bursal disease virus (IBDV) at 1 day of age. Three IBDV+ANV infected chicks were found dead with no apparent clinical signs within 10 days of inoculation with ANV and they had marked urate deposits throughout the body. All of the surviving IBDV+ANV infected chicks had reduced body weight gain, unlike the ANV‐only infected, IBDV‐only infected and non‐infected control chicks.

In a chronological study, all of the ANV‐infected chicks revealed interstitial nephritis accompanied by tubular cell degeneration and lymphoid cell infiltration. Avian nephritis virus antigen was detected with equal sensitivity by fluorescent antibody and immunoperoxidase techniques and was widely distributed in the degenerated epithelial cells. The concentration of serum uric acid in IBDV+ANV infected chicks was higher than that in ANV‐only infected chicks. The antibody against ANV in ANV‐only infected chicks was first detected 8 dpi and its titre increased gradually. In contrast, the antibody in the IBDV+ANV infected chicks was very low and was detected in only three out of seven chicks 16 dpi; the titre was 1:4 in one chick and 1:8 in the other 2 chicks. Coincident with serological results, the number of lgG‐ and IgM‐containing cells in the kidneys and spleen were less in IBDV + ANV‐infected chicks than in ANV‐only infected chicks. These finding suggested that IBDV infection in chicks might influence the immunological response and susceptibility to subsequent ANV infection.  相似文献   

50.
Selective effects of Lipiodolized antitumor agents   总被引:4,自引:0,他引:4  
Lipiodol Ultra-Fluid (Lipiodol) remains selectively in the tumor for an extended time when applied through arteries feeding the tumor. Although lipophilic antitumor drugs are selective when combined with Lipiodol, wide application of common hydrophilic agents is limited, as these compounds are insoluble in oil. We propose "Lipiodolization" of water-soluble agents using as an intermediate Urografin, a water-soluble contrast medium. Thirteen patients with primary hepatocellular carcinoma were treated with this Lipiodol-Urografin system containing antitumor agents. Marked decrease in serum alpha-fetoprotein (AFP) levels, decrease in tumor size in the hepatic imaging, and histologic studies of the resected specimen revealed this mode of therapy to be effective in 10 of 13 patients (77%) with hepatocellular carcinoma. Lipiodolization of antitumor agents is a new approach to selective cancer chemotherapy.  相似文献   
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