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21.
Rapid serodiagnosis of active pulmonary Mycobacterium tuberculosis by analysis of results from multiple antigen-specific tests 总被引:5,自引:0,他引:5 下载免费PDF全文
Okuda Y Maekura R Hirotani A Kitada S Yoshimura K Hiraga T Yamamoto Y Itou M Ogura T Ogihara T 《Journal of clinical microbiology》2004,42(3):1136-1141
We have prospectively analyzed three antigens for serodiagnosis of tuberculosis (TB). These antigens were tuberculous glycolipid antigen, lypoarabinomannan polysaccharide antigen, and antigen 60 (A60), which was derived from purified protein derivatives. Of the 131 patients with active pulmonary TB, 57 were both smear and culture negative and 14 had chronic active pulmonary TB that remained smear positive for >12 months of chemotherapy. One hundred twenty healthy adults were controls. The percentages of patients positive in all three tests were 58.8% for smear-positive active pulmonary TB and 71.4% for chronic active pulmonary TB. When the results of the three serodiagnostic tests were evaluated in combination, the sensitivity increased to 91.5% in patients with active pulmonary TB and to 86.0% in smear- and culture-negative patients. The false-positive rate of the three-test combination was 12.5% in the healthy control groups. In conclusion, it was not possible to detect all of the antibodies against antigenic substances in the cell walls of the tuberculous bacilli in the sera of all TB patients by using available serodiagnostic tests. However, the combined use of tests with three separate antigens maximizes the effectiveness of serodiagnosis. 相似文献
22.
Polycystic ovarian syndrome was induced in adult rats by treatment with continuous illumination to study follicular atresia.
Granulosa cells of regressing antral follicles showed characteristic features of apoptosis ultrastructurally: condensed nuclei,
apoptotic bodies, and phagocytosis of the apoptotic cells and their fragments by neighboring cells. In this study, moreover,
it was observed that an intact granulosa cell was able to ingest another granulosa cell of normal appearance, presumably indicating
an early stage of follicular atresia. The phagocytosing granulosa cell surrounded another granulosa cell to be phagocytosed
by elongated cell processes. Gap junctions developed between the phagocytic cell and the phagocytosed cell. The phagocytic
cell possessed abundant free ribosomes, well-developed rough endoplasmic reticulum and mitochondria, but few lysosomes. The
ingested cell was similar in appearance to the phagocytic cell. In addition, granulosa cells were also observed ingesting
karyopyknotic cells and degenerative organelles, both displayed in large vacuoles filled with fragments of nuclei and organelles.
These findings suggest a process of apoptosis in the granulosa cells during follicular atresia.
This study was presented at the 20th Annual Meeting of the Clinical Electron Microscopy Society of Japan, Fukuoka, September
1–3, 1988. 相似文献
23.
Prospective clinical evaluation of the serologic tuberculous glycolipid test in combination with the nucleic acid amplification test 总被引:4,自引:0,他引:4 下载免费PDF全文
Maekura R Kohno H Hirotani A Okuda Y Ito M Ogura T Yano I 《Journal of clinical microbiology》2003,41(3):1322-1325
We have conducted a prospective controlled multicenter study to evaluate differences in the levels of clinical utility of the tuberculous glycolipid (TBGL) serodiagnostic test and the nucleic acid amplification test in patients with smear-negative active pulmonary tuberculosis (TB). The TBGL test and the PCR test were individually not so useful for the rapid diagnosis of smear-negative active pulmonary TB. However, clinical utility was considerably improved by using the TBGL test and the PCR test in combination, especially in patients with smear-negative and culture-negative active pulmonary TB and in patients with minimally advanced lesions. 相似文献
24.
Hiroaki Takekura Hiroshi Takeshima Seiichiro Nishimura Masami Takahashi Tsutomu Tanabe Veit Flockerzi Franz Hofmann Clara Franzini-Armstrong 《Journal of muscle research and cell motility》1995,16(5):465-480
Summary Ryanodine receptors and dihydropyridine receptors are located opposite each other at the junctions between sarcoplasmic reticulum and either the surface membrane or the transverse tubules in skeletal muscle. Ryanodine receptors are the calcium release channels of the sarcoplasmic reticulum and their cytoplasmic domains form the feet, connecting sarcoplasmic reticulum to transverse tubules. Dihydropyridine receptors are L-type calcium channels that act as the voltage sensors of excitation-contraction coupling: they sense surface membrane and tranverse tubule depolarization and induce opening of the sarcoplasmic reticulum release channels. In skeletal muscle, ryanodine receptors are arranged in extensive arrays and dihydropyridine receptors are grouped into tetrads, which in turn are associated with the four subunits of ryanodine receptors. The disposition allows for a direct interaction between the two sets of molecules.CHO cells were stably transformed with plasmids for skeletal muscle ryanodine receptors and either the skeletal dihydropyridine receptor, or a skeletal-cardiac dihydropyridine receptor chimera (CSk3) which can functionally substitute for the skeletal dihydropyridine receptor, in addition to plasmids for the 2, and subunits. RNA blot hybridization gave positive results for all components. Immunoblots, ryanodine binding, electron microscopy and exposure to caffeine show that the expressed ryanodine receptors forms functional tetrameric channels, which are correctly inserted into the endoplasmic reticulum membrane, and form extensive arrays with the same spacings as in skeletal muscle. Since formation of arrays does not require coexpression of dihydropyridine receptors, we conclude that self-aggregation is an independent property of ryanodine receptors. All dihydropyridine receptor-expressing clones show high affinity binding for dihydropyridine and immunolabelling with antibodies against dihydropyridine receptor. The presence of calcium currents with fast kinetics and immunolabelling for dihydropyridine receptors in the surface membrane of CSk3 clones indicate that CSk3-dihydropyridine receptors are appropriately targeted to the cell's plasmalemma. The expressed skeletal-type dihydropyridine receptors, however, remain mostly located within perinuclear membranes. In cells coexpressing functional dihydropyridine receptors and ryanodine receptors, no junctions between feet-bearing endoplasmic reticulum elements and surface membrane are formed, and dihydropyridine receptors do not assemble into tetrads. A separation between dihydropyridine receptors and ryanodine receptors is not unique to CHO cells, but is found also in cardiac muscle, in muscles of invertebrates and, under certain conditions, in skeletal muscle. We suggest that failure to form junctions in co-transfected CHO cell may be due to lack of an essential protein necessary either for the initial docking of the endoplasmic reticulum to the surface membrane or for maintaining the interaction between dihydropyridine receptors and ryanodine receptors. We also conclude that formation of tetrads requires a close interaction between dihydropyridine receptors and ryanodine receptors. 相似文献
25.
Parathyroid hormone related peptide (PTHrP) was discovered as a causative factor of humoral hypercalcemia of malignancy (HHM). The present study elucidates the histopathological characters of incisor lesions in the HHM rat model. Nude rats were implanted with PTHrP-expressing tumor (LC-6) cells, maintained for 12 weeks, after which the mandibular incisors were collected. Incisor fractures were observed grossly. Microscopically, hypercalcified dentin, dentin niche with osteodentin, and thinning of dentin were observed. Hypercalcified dentin was observed as a basophilic line of calcified dentin without associated odontoblastic changes, whereas dentin niche and thinning of dentin occurred with osteodentin and loss of cell height, respectively. In contrast with hypercalcified dentin, which was distributed throughout the dentin, dentin niche and thinning of dentin were localized to the labial area of the apical and middle region, and to the labial and lingual areas of the middle and incisal region, respectively. These results suggest that hypercalcemia affected the entire calcification process resulting in hypercalcified dentin, and that high PTHrP concentrations affected selective populations of odontoblasts resulting in formation of dentin niche and thinning of dentin. The localization of dentin niche and thinning of dentin also suggest that PTHrP may also be involved odontoblastic development in the rat. 相似文献
26.
Terry L. Riss Masami Ogasawara Kenneth P. Karey David Danielpour Betty H. Stewart David A. Sirbasku 《Methods in Cell Science》1986,10(2):133-150
Summary Serum-free defined media have been developed for assay of the mitogenic effects of growth factors on human MCF-7, human T-47D, and mouse COMMA-D mammary cells as well as for identification of mitogens and inhibitors of GH4C1 rat pituitary tumor cell growth. These lines were shown to grow in vivo in response to a variety of hormones including estrogens and thyroid hormones. With mammary cells, complete hormonally and nutritionally defined media were established that supported continuous passage at 50 to 90% of the serum stimulated rate. The strategy used to measure mitogens for mammary cells was to identify nutritional conditions where the growth rate was reduced greatly without impairing the response to picomolar to nanomolar concentration of growth factors. The effects of polypeptide growth factors and tissue extracts were estimated by their addition to basal medium and measuring cell number increases or labeled thymidine incorporation into DNA. In a variation of this methodology, the MTW9/PL2 rat mammary cells were used to identify secreted autocrine growth factors; nutritionally defined conditions were sought for growth of these rat cells in the complete absence of exogenous growth factors. The factors secreted into the medium were detected by bioassays with COMMA-D or MCF-7 mammary cell lines. The effects of growth factors-inhibitors on pituitary cells were measured by a related method; the GH4C1 cells were grown at less than optimal rates in a defined medium designated TRM-1. Addition of mitogens to TRM-1 stimulated pituitary cell growth whereas addition of inhibitors caused reduced levels of growth. The methods described in this report offer new means of assaying growth factors-inhibitors for a range of mammary and pituitary tumor cells. 相似文献
27.
Tanaka M Katagai K Tsutsumi Y Namekawa T Fukuhara T Takizawa H Nakahara K Ohga E 《Rinsho byori. The Japanese journal of clinical pathology》2002,50(1):68-73
The gold standard diagnostic method for sleep apnea syndrome(SAS) is overnight polysomnography(PSG), but is costly in terms of time and money. We studied the usefulness of a 24-hour ambulatory respirometer equipped with oximeter(Hotmate) for screening of SAS. Seventy-six cases of suspected SAS were enrolled(68 males and 8 females, mean age 51). The correlation between data from Hotmate and PSG was evaluated in 24 cases who underwent both of the tests for the final diagnosis of SAS. There was a good correlation between the two parameters of the data obtained by Hotmate(H) (H-apnea index(AI) vs H-desaturation index(DI)). Among 24 cases who underwent both Hotmate and PSG, there was a good correlation between the data from PSG and Hotmate(PSG-AI vs H-AI: r = 0.80, p < 0.001). Both sensitivity and specificity were highest when screening criteria of H-DI > 15 was utilized(sensitivity = 91.7%, specificity = 66.7%). Our findings suggest that the respiromonitor with oximeter is useful for the screening the patients with SAS. 相似文献
28.
Catalase, a Specific Antigen in the Feces of Human Subjects Infected with Helicobacter pylori 下载免费PDF全文
Nobuyuki Suzuki Masahiko Wakasugi Seigo Nakaya Naomi Kokubo Masami Sato Hirofumi Kajiyama Ryoki Takahashi Haruhisa Hirata Yohji Ezure Yoshihiro Fukuda Takashi Shimoyama 《Clinical and Vaccine Immunology : CVI》2002,9(4):784-788
Recently, we reported the production of three new monoclonal antibodies with high specificity for a Helicobacter pylori antigen suitable for diagnosis of H. pylori infection. The aim of the present study was to identify the antigen recognized by these monoclonal antibodies concerning both H. pylori and the feces of human subjects infected with H. pylori. The cellular antigen was purified from an H. pylori cell extract by immunoaffinity column chromatography with the monoclonal antibody as a ligand. The amino-terminal amino acid sequences (eight residues) of the purified antigen and H. pylori catalase were the same. The molecular weights of native and subunit, specific catalase activity, and UV and visible spectra of the purified antigen were in good agreement with those of H. pylori catalase. The human fecal antigens were purified from two fecal samples of two H. pylori-positive subjects by ammonium sulfate precipitation, CM-Sephadex C50 chromatography, and the same immunoaffinity chromatography used for the H. pylori cellular antigen. The fecal antigens had catalase activity. The amino-terminal amino acid sequences (five residues) of the human fecal antigen and H. pylori catalase were the same. The monoclonal antibodies reacted with the native cellular antigen, but did not react with the denatured antigen, human catalase, and bovine catalase. The results show that the target antigen of the monoclonal antibodies is native H. pylori catalase and that the monoclonal antibodies are able to specifically detect the antigen, which exists in an intact form, retaining the catalase activity in human feces. 相似文献
29.
Kouichi Kashiwase Yoshihide Ishikawa Katsushi Tokunaga Kazue Sawanaka Hatsuya Ohashi Masami Hashimoto Minoru Furuya Ling Lin Tatsuya Akaza Kenji Tadokoro Takeo Juji 《Human immunology》1996,47(1-2):8
Two rare variants of HLA-A locus antigens, tentatively called HLA-A2K and HLA-A9HH, were serologically identified in the Japanese population. A2K and A9HH showed short reaction patterns of a series of anti-A2 and anti-A9 sera, respectively. The latter variant also reacted with some anti-A2 sera. Nucleotide sequences of full-length cDNAs for A2K and A9HH were determined. The results revealed that both antigens are encoded by previously undescribed alleles. The nucleotide sequence of the allele for A2K was identical to that of A*0207 except for a single nucleotide difference in exon 3. The nucleotide sequence of the allele for A9HH was identical to that of A*2402 except for two nucleotides in exon 2. These two nucleotides are shared by all the reported A2 alleles. These sequencing results the allele for A9HH were consistent with the serological cross-reactivity of A9HH with some anti-A2 sera. 相似文献
30.
Uchida M Taida N Kanao M Kagamihara H Kuwajima M 《Rinsho byori. The Japanese journal of clinical pathology》2004,52(7):574-579
We investigated 361 patients with monoclonal gammopathy in whom immunoelectrophoresis was performed (1,037 tests) between 1986 and 2002 at Kagawa Prefectural Central Hospital. In this study, we identified 222 patients with monoclonal gammopathy of undetermined significance (MGUS). Malignant transformation of MGUS to multiple myeloma occurred in 15 patients (6.8%). No significant differences were observed in the means of total protein (TP), albumin (Alb), albumin/globulin ratio (A/G ratio), IgG, IgA, or IgM level in the initial examination between the patients who remained as MGUS and patients with malignant transformation of MGUS. However, the rate of progression to malignancy was high when the levels of normal immunoglobulins other than M protein were below the normal range. Since the number of MGUS cases detected and the number of protein fractionation performed were proportionate, and MGUS was found by protein fractionation in routine tests, protein fractionation is essential for detection of MGUS, and it is necessary to add serum protein fractionation to routine initial examination. In addition, long-term follow-up of patients with monoclonal gammopathy and preparation of a database of patient information are useful for monitoring the outcome. 相似文献