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81.
Genes for immunodominant protein antigens are highly homologous in Mycobacterium tuberculosis, Mycobacterium africanum, and the vaccine strain Mycobacterium bovis BCG. 总被引:2,自引:7,他引:2
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M C Lu M H Lien R E Becker H C Heine A M Buggs D Lipovsek R Gupta P W Robbins C M Grosskinsky S C Hubbard et al. 《Infection and immunity》1987,55(10):2378-2382
The relatedness of immunodominant protein antigens in Mycobacterium tuberculosis, M. africanum, and M. bovis BCG was investigated by comparing the genes that encode major protein antigens in M. tuberculosis with their counterparts in the other two mycobacteria. Genes encoding homologs of M. tuberculosis major protein antigens were isolated from M. africanum and M. bovis BCG by constructing lambda gt11 recombinant DNA expression libraries and screening them with murine monoclonal antibodies and DNA probes. The antibodies were directed against four major protein antigens of M. tuberculosis with molecular masses of 71, 65, 19, and 14 kilodaltons. The isolated M. africanum and M. bovis BCG DNA clones were mapped with restriction endonucleases, and the maps of the mycobacterial genes were confirmed by Southern analysis of mycobacterial genomic DNA. The restriction maps of DNA containing the four genes in M. tuberculosis, M. africanum, and M. bovis BCG are identical, indicating that the immunodominant proteins that they encode are highly homologous in the three mycobacteria. Thus, the immunity against tuberculosis engendered by M. bovis BCG vaccination could be provided, at least in part, by the immune response to these homologous antigens. 相似文献
82.
Chai Ji Dan Yao Ming‐Yan Li Wei‐Jun Chen Sheng‐Liang Lin Zheng‐Yan Zhao 《American journal of medical genetics. Part A》2020,182(9):2102-2109
To describe special facial features of children with Williams syndrome in China by using method of three‐dimensional craniofacial anthropometry. Using three‐dimensional stereo photogrammetric device, 14 craniofacial anthropometric measurements were performed and five indices were calculated in 52 children with Williams syndrome and 208 age and sex matched controls of Han Chinese ethnicity. Except intercanthal width, mouth breadth, morphological face height, nasal height‐breadth index, nasal breadth‐depth index, morphological ear index, the Williams syndrome group under 3 years old were smaller than the control group in the other 12 variables. Compared with the control group, the Williams syndrome group aged 3–5 years old had smaller biocular breadth, nasal length, nasorostral angle, bitragal breadth, ear width, morphological ear index and face depth. The Williams syndrome group aged above 6 years old had smaller biocular breadth, nasal breadth, bitragal breadth, ear width, ear length and face depth than the control group. The craniofacial variability index of the Williams syndrome group was greater than the control group. Greater variation was found among children with Williams syndrome than normal in China, specifically at eye, nose, ear and face shape, which demonstrate the usefulness of three‐dimensional stereo photogrammetric analysis in supporting accurate diagnose of the patient with Williams syndrome. 相似文献
83.
Chung YB Yang HJ Hong SJ Kang SY Lee M Kim TY Choi MH Chai JY Hong ST 《Parasitology research》2003,90(5):365-368
We purified the 17 kDa protein abundant in Clonorchis sinensis crude extracts. The N-terminal amino acid sequence of this protein was determined and an oligonucleotide probe synthesized. Using this probe, the cDNA encoding the protein was cloned and sequenced from the C. sinensis cDNA library. It was found to consist of a total of 150 amino acids and to have 41% conserved homology with the myoglobin of the trematodes Paramphistomum epiclitum and Isoparorchis hypselobagri. The gene product over-expressed in the bacterial system was purified and identified as the same molecule in the adult worms. BALB/c mouse sera raised against the adult 17 kDa protein revealed that this myoglobin was distributed throughout the parenchymal tissues except for the eggs and reproductive organs and that the protein may be involved in the survival of C. sinensis in the oxygen-depleted environment of the host. 相似文献
84.
Plurihormonal pituitary adenomas: immunostaining of all pituitary hormones is mandatory for correct classification 总被引:4,自引:0,他引:4
AIMS: We studied the clinicopathological characteristics of plurihormonal pituitary adenomas. METHODS AND RESULTS: The study material included 167 plurihormonal adenomas, which consisted of 31% of the surgically removed pituitary adenomas that we collected during a 12-year period. The mean age of patients with plurihormonal adenoma was 45.7 years (range 13-75 years). There were 86 men and 81 women. All tumours were fully classified by immunohistochemical staining for seven pituitary hormones or subunits. Thirty immunohistochemical subtypes of plurihormonal adenomas were recognized. Hormonal symptoms were present in 70% of patients, while serum hormonal levels were increased in 89% of patients. Most patients had symptoms related to only one of the hormones and only 7% of patients had symptoms related to two hormones. The most common hormonal symptom was acromegaly (50%); symptoms related to hyperprolactinaemia ranked second (20%). Double immunostaining of all the possible combinations of the hormones was performed in 30 selected tumours, and they all showed mixtures of hormones in individual adenoma cells in any hormonal combinations studied. The latter finding supported the view that plurihormonal adenomas are monomorphous adenomas. CONCLUSIONS: Plurihormonal adenomas are common pituitary adenomas. Immunohistochemical staining of all pituitary hormones is mandatory for correct classification. 相似文献
85.
Evaluation of fluorescent antinuclear antibody assays, Crithidia luciliae substrate, and single-stranded DNA-binding capacity in diagnosis of four rheumatic diseases.
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Sera from groups of patient with systemic lupus erythematosus, mixed connective tissue disease, rheumatoid arthritis, and progressive systemic sclerosis and normal controls were compared, using different antinuclear antibody assays. Hep-II cells, used as a substrate for the detection of antinuclear antibodies, appeared to be more sensitive than rat liver substrate. In addition, the fluorescent patterns were easier to identify on Hep-II cells. All systemic lupus erythematosus sera with antibodies reactive with kinetoplasts of Crithidia luciliae had binding greater than 43% for single-stranded DNA. Based on the high sensitivity of the Hep-II substrate and the relative specificity of high (greater than 43%) binding for single stranded DNA by sera from patients with systemic lupus erythematosus, it appears that these two tests are most useful in differential diagnosis and for the detection of systemic lupus erythematosus. 相似文献
86.
Chia-Ying Liu Chih-Cheng Lai Hsiu-Tzy Chiang Min-Chi Lu Ling-Fang Wang Tsai-Ling Tsai Mei-Yu Kang Yi-Ni Jan Yi-Ting Lo Wen-Chien Ko Shu-Hui Tseng Chun-Ming Lee Po-Ren Hsueh 《Journal of microbiology, immunology, and infection》2019,52(1):62-74
Background/purpose
This study investigated the distribution and persistence of multidrug resistant organisms (MDROs) including methicillin-resistant Staphylococcus aureus (MRSA), carbapenem-resistant Enterobacteriaceae (CRE), carbapenem-resistant Pseudomonas aeruginosa (CRPA), and multidrug-resistant Acinetobacter baumannii (MDRAB) in six long-term care facilities (LTCFs).Methods
We investigated the distribution of MDROs in residents of six LTCFs and their environments from January to December 2016 (intervention period). Active surveillance of colonization of MDROs was performed by culturing rectal and nasal swab samples from the residents every three months. Multilocus sequence typing (MLST) was conducted, and genes for panton-valentine leukocidin (PVL) from MRSA isolates were determined.Results
A total of 521 samples were positive for MDROs, and MRSA was the most common organism (65.1%), followed by MDRAB (11.3%), carbapenem-resistant Klebsiella pneumoniae (11.1%), carbapenem-resistant Escherichia coli (4.6%), and carbapenem-resistant P. aeruginosa (2.1%, n = 11). By a linear regression model, positive MRSA isolates from the environment were found to be statistically significant and associated with the number of colonized LTCF residents (p = 0.01), while the timing of the surveillance culture was not (p = 0.227). The main MLST types associated with PVL-production were sequence type (ST) 59, (40.0%, 24/60), ST30 (21.4%, 3/14), ST8 (87.5%, 14/16), and ST45 (3.6%, 1/28). The susceptibility rates of tetracycline (96.7%), trimethoprim-sulfamethoxazole (96.7%), and ciprofloxacin (81.7%) were statistically significant and higher in MRSA ST59, compared to the rates in MRSA ST45 isolates.Conclusions
MRSA was the most commonly colonized MDRO, both in the LTCF residents and in the environment, followed by MDRAB and carbapenem-resistant K. pneumoniae. 相似文献87.
H W Peng T S Su S H Han C K Ho C H Ho K N Ching B N Chiang 《Journal of medical virology》1988,24(4):405-412
In order to study the prevalence of hepatitis B virus (HBV) in the adult population of Taiwan, we screened for the presence of HBV DNA in 205 blood samples from adult (20-59-year-old) volunteers. According to the serological markers of HBV, samples were divided into three groups: group I (173 subjects) was negative for both HBsAg and HBeAg; group II (14 subjects) was positive for both HBsAg and HBeAg; and group III consisted of 18 subjects who were HBsAg-positive but HBeAg-negative. Plasma HBV DNA was not detected in group I, but it was found in 85.7% and 11.8% of samples in group II and group III, respectively. A free-form HBV DNA was found in 14.3% of the leukocyte samples in group II. Furthermore, an integrated form of HBV DNA was detected in the leukocytes of two cases of group I who remained healthy based on clinical data. HBV DNA was also detected in the spermatozoa and liver cells of one of the cases. 相似文献
88.
This study investigated the role of trigeminal subnucleus caudalis (Vc) P2X receptors in the mediation of central sensitization induced in nociceptive neurons in subnucleus oralis (Vo) by mustard oil (MO) application to the tooth pulp in anesthetized rats. MO application produced a long-lasting central sensitization reflected in neuroplastic changes (i.e., increases in neuronal mechanoreceptive field size and responses to innocuous and noxious mechanical stimuli) in Vo nociceptive neurons. Twenty minutes after MO application, the intrathecal (i.t.) administration to the rostral Vc of the selective P2X(1), P2X(3), and P2X(2/3) receptor antagonist, 2'-(or 3'-)O-trinitrophenyl-ATP (TNP-ATP), significantly and reversibly attenuated the MO-induced central sensitization for more than 15 min; saline administration had no effect. Administration to the rostral Vc of the selective P2X(1), P2X(3), and P2X(2/3) receptor agonist, alpha,beta-methylene ATP (alpha,beta-meATP, i.t.) produced abrupt and significant neuroplastic changes in Vo nociceptive neurons, followed by neuronal desensitization as evidenced by the ineffectiveness of a second i.t. application of alpha,beta-meATP and subsequent MO application to the pulp. Administration to the rostral Vc of the selective P2X(1) receptor agonist beta,gamma-methylene ATP (beta,gamma-meATP, i.t.) produced no significant neuroplastic changes per se and did not affect the subsequent MO-induced neuroplastic changes in Vo nociceptive neurons. These results suggest that P2X(3) and possibly also the P2X(2/3) receptor subtypes in Vc may play a role in the initiation and maintenance of central sensitization in Vo nociceptive neurons induced by MO application to the pulp. 相似文献
89.
Glucosyltransferases of viridans streptococci are modulins of interleukin-6 induction in infective endocarditis
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The glucosyltransferases (GTFs) of viridans streptococci, common pathogens of infective endocarditis, are extracellular proteins that convert sucrose into exopolysaccharides and glucans. GTFs B, C, and D of Streptococcus mutans are modulins that induce, in vitro and in vivo, the production of cytokines, in particular interleukin-6 (IL-6), from monocytes. The roles of S. mutans GTFs in infectivity and inflammation in situ were tested in a rat experimental model of endocarditis. No significant differences in infectivity, in terms of 95% infective dose and densities of bacteria inside vegetations, were observed between laboratory strain GS-5 and two clinical isolates or isogenic mutant NHS1DD, defective in the expression of GTFs. In aortic valves and surrounding tissues, IL-6 was detected by Western blots and immunostaining 24 h after GS-5 infection, was maintained over 72 h, and was followed by production of tumor necrosis factor alpha but not IL-1beta. Animals infected with NHS1DD showed markedly lower levels of IL-6 (less than 5% of that of parental GS-5-infected rats), while tumor necrosis factor alpha was unaffected. In contrast, animals infected with NHR1DD, another isogenic mutant expressing only GtfB, showed a much smaller reduction (down to 56%). These results suggest that GTFs are specific modulins that act during acute inflammation, inducing IL-6 from endothelial cells surrounding the infected valves without affecting bacterial colonization in vegetations, and that IL-6 might persist in chronic inflammation in endocarditis. 相似文献
90.
Spontaneous autoimmune disease in NZB and (NZB x NZW)F1 (B/W) mice is associated with a spectrum of lymphoproliferative abnormalities, but the relationship between autoimmunity and lymphoproliferation is poorly understood. Lymphomas occur commonly in NZB mice, but they appear to be rare in B/W mice, perhaps because B/W mice die of murine lupus before the lymphomas are evident. We recently reported that autoimmune disease in B/W mice could be reversed by weekly treatment with monoclonal antibodies to the L3T4 antigen on "helper/inducer" T cells. This has enabled us to examine the evolution of lymphoproliferation in B/W mice that survive beyond the usual life span, both in long-term survivors of treatment with anti-L3T4 and in the occasional B/W mouse that spontaneously survives beyond 1 year of age. We find that all of these mice develop marked proliferation of a distinct subpopulation of B cells that express the Ly-1 antigen in low density. These Ly-1+ B cells account for a 2-10-fold increase in the number of splenic, lymph node and peripheral blood lymphocytes. The Ly-1 B cells in individual mice are restricted in their expression of immunoglobulin light chains, suggesting a clonal origin. NZB mice. develop similar proliferation of Ly-1 B cells, suggesting that this is due to underlying genetic and/or viral factors in NZB and B/W mice, and that it is not the result of treatment with anti-L3T4. Although recent studies have implicated Ly-1 B cells in the production of autoantibodies, proliferation of Ly-1 B cells in B/W mice was not associated with production of anti-DNA antibodies or with any paraprotein. 相似文献