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11.
Kitada S Maekura R Toyoshima N Naka T Fujiwara N Kobayashi M Yano I Ito M Kobayashi K 《Clinical and diagnostic laboratory immunology》2005,12(1):44-51
We report the development of a serodiagnostic method for Mycobacterium avium complex (MAC) disease with an enzyme immunoassay (EIA) with the MAC-specific glycopeptidolipid (GPL) core as the antigen. In this study, we confirmed by EIA that the GPL core antibody was in the sera of immunocompetent patients with MAC disease. The EIA for quantifying the GPL core antibody was evaluated as a clinical tool for serodiagnosis of pulmonary MAC disease. A significant increase in GPL core antibodies (immunoglobulins G, A, and M) was detected in sera of patients with MAC pulmonary diseases when they were compared to patients who were colonized with MAC, patients with Mycobacterium kansasii disease or tuberculosis, and healthy subjects. The sensitivities and specificities of the GPL core-based EIA for diagnosis of MAC pulmonary disease were 72.6% and 92.2%, respectively, for IgG, 92.5% and 95.1%, respectively, for IgA, and 78.3% and 91.0%, respectively, for IgM. The best sensitivity and specificity were obtained by measuring immunoglobulin A antibodies against GPL core antigen. The level of GPL core antibodies reflected disease activity, since it decreased in cured MAC patients who had responded to chemotherapy. Measurement of serum antibodies against GPL core is useful for both diagnosis and assessment of disease activity in MAC disease of the lung. 相似文献
12.
Seigo Maeo Yoichi Ajioka Hidenobu Watanabe Masaaki Kobayashi Michio Kobayashi 《Pathology international》1995,45(5):359-365
Well-differentiated colorectal adenocarcinomas are subclassified into carcinoma with high-grade atypia (CAH) and carcinoma with low-grade atypia (CAL) based on their cellular atypia. It is proposed that CAH and CAL are different in histologic prognostic factors and that the former should be regarded as carcinoma with high-grade malignancy and the latter as low-grade malignancy. In this study, the differences in cell-proliferative activity between CAH and CAL were examined using a monoclonal antibody to the proliferating cell nuclear antigen (PCNA). The PCNA index and mitotic index of 27 early colorectal carcinomas (9 CAL, 5 CAH, and 13 carcinomas with mixed low- and highgrade atypia) was evaluated in relation to their depth of invasion. In intra-mucosal lesions, both indices were higher in CAH (78%, 0.89%) than in CAL (68%, 0.47%; P <0.01). In lesions invading into the submucosa, the PCNA and mitotic indices were also higher in CAH (7596, 0.65%) than in CAL (35%, 0.19%; P <0.01). A significant correlation was observed between the PCNA index and the mitotic index in the mucosal lesions (P<0.05). These results indicate that CAH has a higher proliferative activity than CAL, and support the current authors' proposal that CAH is a high-grade malignancy and CAL a low-grade malignancy. 相似文献
13.
Multiple time axes for representation of echo delays in the auditory cortex of the mustached bat 总被引:1,自引:0,他引:1
The properties of the orientation sound (pulse) of the Jamaican mustached bat, Pteronotus parnellii parnellii is the same as the Panamanian mustached bat, P.p. rubiginosus. It consists of four harmonics, each containing a long constant-frequency (CF) component followed by a short frequency-modulated (FM) component. Thus, there are eight components in total: CF1-4 and FM1-4. The combination-sensitive area of the auditory cortex in P.p. parnellii consists of two major divisions (FM-FM and CF/CF areas) as in P.p. rubiginosus. The FM-FM area projects to the dorsal fringe (DF) and other areas. Response latencies of neurons in the DF area are longer than those in the FM-FM area. The distribution of latencies is unimodal for the FM-FM area, but bimodal for the DF area. In this electrophysiological study of the response properties of neurons in the DF and FM-FM areas, our aim was to find out how signal processing might be different between the two areas. Both the FM-FM and DF areas consist of three types of FM-FM combination-sensitive neurons: FM1-FM2, FM1-FM3, and FM1-FM4. They do not respond or respond poorly to pulse alone, echo alone, single CF tones or single FM sounds. But they show strong facilitation of response to the echo when it is delivered with particular delays from the pulse. The essential elements in the pulse-echo pair for facilitation are the FM1 of the pulse and FM2 or FM3 or FM4 of the echo. In both the FM-FM and DF areas, the great majority of neurons show short-lasting facilitation, and other neurons show long-lasting facilitation. FM-FM neurons are tuned to particular echo delays, i.e., target ranges. In both the FM-FM and DF areas, the width of a delay-tuning curve is linearly related to the value of a best delay. There is no sign that processing of range information is more specialized in the DF area than the FM-FM area. In both the FM-FM and DF areas, three types of FM-FM neurons form independent clusters. Along the major axis of each cluster, best delays for facilitative responses of neurons systematically change according to the loci of the neurons. The more posterior the location, the longer the best delay is. Therefore, there are six time (i.e., range) axes in total. The time axis in the DF area is shorter than that in the FM-FM area.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
14.
Distinctions between microglial cells and peripheral macrophages with regard to adhesive activities and morphology. 总被引:1,自引:0,他引:1
K Toku J Tanaka S Fujikata Y Hamamoto Y Horikawa K Miyoshi N Tateishi Y Suzuki N Maeda 《Journal of neuroscience research》1999,57(6):855-865
Activated microglial cells and peripheral macrophages are hardly distinguishable from the viewpoints of morphology and function. There are various immunological markers common to both microglial cells and peripheral macrophages. In the present study, however, we found that microglial cells have distinct characters in terms of adhesion and morphology. By using a "rheoscope," that is an apparatus to rheologically measure the strength of cell adhesion to substrates, rat microglial cells were found to attach to polystyrene dishes much more weakly than alveolar and peritoneal macrophages. Interferon-gamma (IFNgamma) strengthened the adhesion of alveolar and peritoneal macrophages, whereas it weakened that of microglial cells. Morphological changes of microglial cells induced by IFNgamma were also different from those of peripheral macrophages. Furthermore, alveolar and peritoneal macrophages produced NO in response to IFNgamma, while microglial cells did not. When cultured on astrocyte-derived extracellular matrix (AsECM) in serum-free medium, only microglial cells extended multiple ramified processes. Conversely, alveolar and peritoneal macrophages on AsECM shrunk their ruffling membrane and rounded up. These distinctions between microglial cells and macrophages may reflect differences in cell lineages as well as environments in which individual cells reside. 相似文献
15.
16.
Naofumi Ohsawa Shinya Uchino Takao Saito Masaki Miyahara Tokuji Inoue Seigo Kitano 《International journal of clinical oncology / Japan Society of Clinical Oncology》1997,2(4):230-234
Background Deletions involving chromosome 9p21, on which the tumor suppressor genep16/MTS1 is located, have been noted in esophageal cancer. We investigated the relationship between the deletion of chromosome 9p21–22
and the clinical features of esophageal cancer.
Methods We examined the loss of heterozygosity (LOH) on chromosome 9p21–22 in 56 esophageal cancers using polymerase chain reaction
(PCR) analysis and 2 microsatellite markers (RPS6 and IFNA).
Results In 18 out of 50 informative cases (36%), LOH had occurred at 1 or 2 loci on chromosome 9p21–22. We found no relationship between
LOH on chromosome 9p21–22 and patient sex, age tumor length, location, histologic differentiation, depth of tumor invasion,
the extent of lymph node metastasis, histologic stage, or curability. Among 35 patients without an absolute noncurative resection,
the mean survival of 11 patients with LOH on chromosome 9p21–22 was 19.3 months, compared with 42.3 months for 24 patients
with a normal allele; thus, the survival rate of those with LOH was significantly lower than that of patients without LOH
on chromosome 9p21–22 (log-rank test;P=0.03).
Conclusion These data suggest that LOH on chromosome 9p21–22, on which the cell-cycle regulatorp16/MTS1 gene is located, may be related to cancer development, and probably can serve as a clinical marker for evaluating a patient's
prognosis. 相似文献
17.
Arai H Ishiguro K Ohno H Moriyama M Itoh N Okamura N Matsui T Morikawa Y Horikawa E Kohno H Sasaki H Imahori K 《Experimental neurology》2000,166(1):201-203
Cerebrospinal fluid (CSF) tau protein phosphorylated at both Thr231 and Ser235 sites (CSF/phospho-tau(231-235)) and total tau (CSF/total-tau) were quantified by sandwich ELISA in 20 patients with mild cognitive impairment (MCI) who eventually developed AD on follow-up as well as seven memory complainers with no objective memory loss. 13/20 (65%) of the MCI patients had high CSF/total-tau and detectable levels of CSF/phospho-tau(231-235), whereas these markers were low and under a detectable level in all of the memory complainers. Although either a total-tau, phospho-tau measurement or a combination of these can help in predicting if MCI will develop AD, our results suggest that the pathogenic steps of AD may be at the stage that finally leads to an accumulation of abnormally phosphorylated tau and neuron death, at least in some brain areas, when MCI patients present with the earliest detectable clinical symptoms of dementia. 相似文献
18.
Hinokio Y Horikawa Y Furuta H Cox NJ Iwasaki N Honda M Ogata M Iwamoto Y Bell GI 《Diabetes》2000,49(2):302-305
19.
No Improvement of Adult Height in Non-growth Hormone (GH) Deficient Short
Children with GH Treatment
Toshiaki Tanaka Kenji Fujieda Susumu Yokoya Akira Shimatsu Katsuhiko Tachibana Hiroyuki Tanaka Takakuni Tanizawa Akira Teramoto Toshiro Nagai Yoshikazu Nishi Yukihiro Hasegawa Kunihiko Hanew Keinosuke Fujita Reiko Horikawa Goro Takada Masao Miyashita Tadashi Ohno Kazuo Komatsu 《Clinical Pediatric Endocrinology》2006,15(1):15-21
It is still in doubt whether the standard-dose growth hormone (GH) used in Japan (0.5
IU/kg/week, 0.167 mg/kg/week) for growth hormone deficiency is effective for achieving
significant adult height improvement in non-growth hormone deficient (non-GHD) short
children. We compared the growth of GH-treated non-GHD short children with that of
untreated short children to examine the effect of standard-dose GH treatment on non-GHD
short children. GH treatment with recombinant human growth hormone (rhGH) was started
before the age of 11 yr in 64 boys and 76 girls with non-GHD short stature registered at
the Foundation for Growth Science who have now reached their adult height. In 119
untreated boys and 127 untreated girls whose height standard deviation score (SDS) was
below –2 SD at the age of 6 yr, height growth was followed until 17 yr. Height SDS was
significantly lower before GH treatment in the GH-treated group than at the age of 6 yr in
the untreated group, in both sexes. Adult height and adult height SDS were significantly
greater in the untreated group than in the GH-treated group, in both sexes, although the
change in height SDS did not differ significantly. Height SDS was significantly lower
before GH treatment in the GH-treated group than at the age of 6 yr in the untreated
group, so 57 boys and 57 girls whose height SDS at the age of 6 yr in the untreated group
closely matched the height SDS before GH treatment in the GH-treated group were chosen for
comparison. Height SDS did not differ significantly between the GH-treated group before GH
treatment and the untreated group at the age of 6 yr, nor were there differences between
these subgroups in adult height, adult height SDS, or height SDS change, in either sex.
The effect of GH treatment is reported to be dose-dependent and doses over 0.23 mg/kg/week
are reported to be necessary to improve adult height in non-GHD short children. Currently,
the GH dose is fixed at 0.175 mg/kg/week in Japan, and we expected to find, and indeed
concluded, that ordinary GH treatment in Japanese, non-GHD short children does not improve
adult height. 相似文献
20.
Yoichi Kohno Shigeyuki Kitamura Seigo Sanoh Kazumi Sugihara Nariaki Fujimoto Shigeru Ohta 《Drug metabolism and disposition》2005,33(8):1115-1123
When chalcone and trans-4-phenyl-3-buten-2-one (PBO) were incubated with liver microsomes of untreated rats in the presence of NADPH, 4-hydroxychalcone and trans-4-(4-hydroxyphenyl)-3-buten-2-one (4-OH-PBO), respectively, were formed as major metabolites. Two minor metabolites of chalcone, 4'-hydroxychalcone and 2-hydroxychalcone, were also observed. The oxidase activity affording 4-hydroxychalcone was inhibited by SKF 525-A, disulfiram, ketoconazole, and alpha-naphthoflavone. The oxidase activities leading to 4-hydroxychalcone and 4'-hydroxychalcone were enhanced in liver microsomes of 3-methylcholanthrene- and phenobarbital-treated rats, respectively. The activity generating 2-hydroxychalcone was enhanced in liver microsomes of 3-methylcholanthrene- and dexamethasone-treated rats. The oxidation of PBO to 4-OH-PBO was inhibited by SKF 525-A, ketoconazole, disulfiram, and sulfaphenazole. This activity was enhanced in liver microsomes of 3-methylcholanthrene-, acetone- and phenobarbital-treated rats. 4-Hydroxylation, 4'-hydroxylation, and 2-hydroxylation of chalcone were catalyzed by rat recombinant cytochrome P450 1A1, 1A2, and 2C6; by 1A1 and 2C6; and by 1A1 and 3A1, respectively. PBO was oxidized by cytochrome P450 1A1, 1A2, 2C6, and 2E1. Chalcone and PBO were negative in an estrogen reporter assay using estrogen-responsive human breast cancer cell line MCF-7. However, 4-hydroxychalcone, 2-hydroxychalcone, 4'-hydroxychalcone, and 4-OH-PBO exhibited estrogenic activity. 相似文献