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Biomedical subjects

H Yamaguchi

Publications and source records attributed to H Yamaguchi.

At least 145 records · Page 8Linked to original sources
PubMed2001

Association of seropositivity for antibody to Chlamydia-specific lipopolysaccharide and coronary artery disease in Japanese men.

Recent studies suggest an association between Chlamydia pneumoniae infection and coronary artery disease (CAD). To examine this relationship in Japanese men, serum IgA and IgG antibodies to Chlamydia-specific lipopolysaccharide were measured by enzyme-linked immunosorbent assay in 507 patients with CAD and 200 age-matched controls. CAD patients were divided into (1) 269 patients with myocardial infarction (MI) and (2) 238 patients with chronic coronary heart disease (CCHD). Compared with the control group, the CAD group did not differ in the prevalences of both antibodies (IgA: 23.7 vs 18.0%, p=0.10; IgG: 52.7 vs 51.0%, p=0.6). The index of IgG antibody was not significantly different between CAD and control groups (median 1.19 vs 1.18, p=0.3), whereas the index of IgA antibody was significantly higher in CAD than control group (median 0.60 vs 0.46, p<0.0001). Compared with the control group, the MI group had a significantly higher prevalence of IgA antibody (28.6 vs 18.0%, p=0.007); however, there was no difference in the prevalence of IgG antibody (58.0 vs 51.0%, p=0.13). The CCHD group did not differ in the prevalences of both antibodies (IgA: 18.1 vs 18.0%, p=0.9; IgG: 45.6 vs 51.0%, p=0.2). After the adjustment for coronary risk factors, odds ratios (ORs) of seropositive antibodies for CAD were 1.59 [95% confidence interval (CI): 0.88-2.87, p=0.12] for IgA seropositivity and 0.92 (95%CI: 0.58-1.47, p=0.7) for IgG seropositivity in all cases. In the MI and control groups, ORs of seropositive antibodies for MI were 2.67 (95%CI: 1.32-5.38, p=0.007) for IgA seropositivity, and 1.36 (95%CI: 0.79-2.36, p=0.2) for IgG seropositivity. This study discovered that IgA antibody to Chlamydia was significantly associated with CAD, especially with MI, in Japanese Men and the findings suggest that chronic infection of Chlamydia may be linked to the pathogenesis of MI.

Aged↗
PubMed2001

Potentially protective effects of the Ser447-Ter mutation of the lipoprotein lipase gene against the development of coronary artery disease in Japanese subjects via a beneficial lipid profile.

Several DNA variants at the lipoprotein lipase (LPL) gene locus have been found to be associated with the plasma lipid levels and the prevalence of coronary artery disease (CAD). In particular, the Ser447-termination (Ter) mutation at the exon 9 of the LPL gene has the potential to elevate the plasma high-density lipoprotein (HDL) levels, but it remains unknown in the Japanese population. The present study investigated 93 CAD patients and 96 age- and sex-matched healthy controls. The Ser447-Ter mutation was determined by polymerase chain reaction restriction fragment length polymorphism method. The allelic frequency of the Ser447-Ter mutation was 0.103 in all subjects. The Ser447-Ter (GG and CG) group was associated with significantly higher levels of plasma HDL-cholesterol (p<0.001) and lower levels of plasma triglyceride than the CC group (p<0.02). The peak particle size of low-density lipoprotein (LDL) was significantly larger in the Ser447-Ter (GG and CG) group than in CC group (p<0.05). The frequency of the Ser447-Ter genotype in GG and CG was significantly lower in CAD than in the controls (11.9% vs 26%, odds ratio = 0.38; 95% confidence interval, 0.18-0.81; p<0.02). These results suggest that the Ser447-Ter mutation of the LPL gene is associated with high plasma HDL-cholesterol levels, low plasma triglyceride levels and a larger LDL particle size. This mutation may have a protective effect against the development of CAD via its favorable lipoprotein profile.

Aged↗
PubMed2001

Surgical repair of coronary artery aneurysm after percutaneous coronary intervention.

Two cases of coronary artery aneurysm after percutaneous coronary intervention are presented. In both cases, follow-up coronary angiography revealed an expanding saccular aneurysmal formation and restenosis or a new lesion. Consequently, surgical repair and revascularization were indicated. The intraoperative angioscope was used to identify the aneurysm, which had not been visible on the heart surface in one case. Its optic fiber light was a useful guide, but little information was obtained from direct vision because of the small caliber of the angioscope. Plication of the aneurysm and bypass grafting distal to the aneurysm were performed. A whitish and thick-walled aneurysm was easily found in one case, in which ligation of the aneurysm was attempted with added distal bypass. The postoperative course was uneventful in both cases, and follow-up angiography showed disappearance of the aneurysm with patent grafts. There was a fragile thrombus inside both the aneurysmal sacs, which might have caused myocardial infarction and, therefore, justified the surgical repair of the aneurysm with concomitant revascularization.

Aged↗
PubMed2001

An elderly patient with gastric carcinoma developing multiple metastasis in skeletal muscle.

We present a 70-year-old man with gastric carcinoma developing multiple metastasis in skeletal muscle. He had a right supraclavicular lymph node swelling. Brain, chest and abdomen CT scans revealed metastatic lesions in the brain, lung, liver and bilateral adrenal glands. Further, CT showed a ring enhanced soft-tissue mass in the left lumbar muscle. Needle aspirate of the mass in both the left lumbar muscle and the right enlarged supraclavicular lymph node revealed cells suggestive of poorly differentiated adenocarcinoma. Upper gastrointestinal endoscopic evaluation demonstrated an advanced gastric carcinoma. Two months after admission, the tumor in the left lumbar muscle had grown and some new lesions in the left iliopsoas muscles appeared. Intramuscular metastasis from gastric carcinoma is an extremely rare phenomenon.

Adenocarcinoma↗
PubMed2001

Platelet-derived growth factor BB-induced p38 mitogen-activated protein kinase activation causes cell growth, but not apoptosis, in vascular smooth muscle cells.

The aim of this experiment was to examine the regulation of p38 mitogen-activated protein (MAP) kinase by platelet-derived growth factor (PDGF)-BB and its biological effects on rat cultured vascular smooth muscle cells (VSMCs). VSMCs were obtained from aortae of male Wistar rats by the media explant technique. After being stimulated by PDGF-BB with or without the p38 MAP kinase-specific inhibitor, SB-203580, the cells were solubilized, and the levels of phosphorylated p38 MAP kinase were examined by immunoblot analysis. The amounts of DNA synthesis and content were measured by using [3H]-thymidine and Hoechst-33258 dye, respectively. The detection of apoptotic cells was evaluated by the TUNEL method. PDGF-BB could phosphorylate p38 MAP kinase dose-dependently, and the phosphorylation was specifically inhibited by SB-203580 in a dose-dependent manner. However, PDGF-BB did not affect the protein level of p38 MAP kinase. Both [3H]-thymidine incorporation and total cellular DNA content were increased by PDGF-BB, and these elevations were prevented by SB-203580. In contrast, PDGF-BB-stimulated VSMCs did not show apoptotic change in spite of the presence or absence of SB-203580. These results established that PDGF-BB activated p38 MAP kinase and subsequently regulated cell growth in VSMCs, providing a molecular mechanism by which p38 MAP kinase can cause the development of cardiovascular diseases, including atherosclerosis.

Animals↗
PubMed2001

Relationship between plasma homocysteine levels and saphenous vein graft disease after coronary artery bypass grafts.

The long-term efficacy of coronary artery bypass graft (CABG) surgery is limited by saphenous vein graft (SVG) disease. Elevated levels of plasma homocysteine are a known independent risk factor for cardiovascular disease. However, its influence on the patency of SVG is unknown. To determine whether plasma homocysteine levels are related to SVG disease after CABG we measured homocysteine levels in 80 patients who underwent CABG (age: 64+/-8, interval after bypass surgery: 6.4+/-3.1, range: 1-13 years). The patients were divided into a vein graft disease group (more than 50% angiographical stenosis in any vein graft, n=40) and a no-vein graft disease group (<50% stenosis in any vein graft, n=40). The presence of a mutation in the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene was also determined by polymerase chain reaction. Homocysteine levels in the vein graft disease group were significantly higher than in the no-vein graft disease group (11.2 vs. 9.1 micromol/l, p=0.01). Multiple regression analysis showed that the interval after CABG was an independent factor for SVG disease (odds ratio: 1.014, 95% confidence intervals: 1.003-1.025, p=0.013) and elevated levels of homocysteine tended to be an independent factor for SVG disease (odds ratio: 1.098, 95% confidence intervals: 0.994-1.213, p=0.067). There was no significant difference in MTHFR genotypes between the two groups. These findings indicate that elevated levels of plasma homocysteine are related to SVG disease after CABG.

Case-Control Studies↗
PubMed2001

Immunohistochemical diagnosis of Cryptococcus neoformans var. gattii infection in chronic meningoencephalitis: the first case in Japan.

Cryptococcus neoformans (C. neoformans) var. gattii infection usually occurs in tropical and subtropical areas, and rarely in the northern hemisphere. We report the first Japanese with cryptococcal meningoencephalitis caused by C. neoformans var. gattii infection that occurred during a trip to Australia. This agent was identified in a cerebellar biopsy specimen by immunohistochemical technique with serotype-specific anti-sera. Because the meningitis caused by it did not respond well to conventional therapy, we used an aggressive therapeutic regimen to successfully treat the patient. Even in areas where C. neoformans var. gattii does not exist, this infection should be considered possible as a travel-related infection.

Aged↗
PubMed2001

Genotype Arg/Arg, but not Trp/Arg, of the Trp64Arg polymorphism of the beta(3)-adrenergic receptor is associated with type 2 diabetes and obesity in a large Japanese sample.

OBJECTIVE: Despite a large number of studies, no association of the Trp64Arg polymorphism of the beta(3)-adrenergic receptor gene with obesity and type 2 diabetes has yet to be clearly elucidated. We examined the associations in a large population-based sample. RESEARCH DESIGN AND METHODS: A total of 1,685 subjects (935 women and 750 men, aged 58.7 +/- 12.4 years) from a cohort population (n = 3,706) of the Funagata Diabetes Study were divided into three groups according to genotypes: Trp/Trp (n = 1,155), Trp/Arg (n = 486), and Arg/Arg (n = 44). Glucose tolerance was diagnosed according to the 1985 World Health Organization criteria. Subjects who had a BMI > or =30 kg/m(2) were considered obese. Associations with the traits related to obesity, diabetes, hypertension, and dyslipidemia were also examined. The chi(2) test and analysis of variance were used for the association studies and to assess the differences in the traits' values, respectively. RESULTS: More subjects with genotype Arg/Arg were obese and had diabetes (13.6% for each) than those with genotype Trp/Trp (3.29%, P < 0.001; and 4.16%, P = 0.007, respectively) or genotype Trp/Arg (2.06%, P < 0.001; and 5.97%, P = 0.051, respectively). No significant differences in the frequencies of occurrence of these conditions were observed between genotypes Trp/Arg and Trp/Trp. Traits related to obesity, such as percent body fat (28.82 +/- 7.95 vs. 25.93 +/- 7.21, P = 0.038) and BMI (25.07 +/- 3.84 vs. 23.63 +/- 3.18, P = 0.018), were higher in the genotype Arg/Arg than in the genotype Trp/Trp groups. CONCLUSIONS: Genotype Arg/Arg, but not Trp/Arg, of the beta(3)-adrenergic receptor was associated with both obesity and type 2 diabetes in a large Japanese sample.

Aged↗
PubMed2001

Liver segment S2 is consistently located at the dorsal side of S3 but sometimes at the right and/or caudal side of S3.

After preparing the frontal section including the origin of the left portal trunk at the hilar region, the left anatomical lobes of 111 human livers were dissected to reveal the segmental configuration based on the supplying portal vein branches. S2 was consistently located dorsal to S3. However, in contrast to the description in common textbooks for medical students, 19.8% of the specimens carried a paradoxical segmental configuration showing a "caudal and/or rightward" S2 in combination with a "cranial and/or leftward" S3 in the frontal section through the ventral part of the hilar region. The caudal and rightward cases were associated with a specific arrangement of S2 and S3 segmental stems in which the S3 stem ran relatively upward to spread over S2 or both stems ran almost horizontal, respectively. In routine diagnostic radiology, identification of S2 and S3 might sometimes be biased by the generally accepted notion that S2 should be located at the dorsal, cranial and left side of S3.

Humans↗
PubMed2001

[Specific and rapid identification of Malassezia species based on the DNA sequences of nuclear ribosomal internal transcribed spacer 1 regions].

Species identification of genus Malassezia is important in epidemiological and etiological studies, however, is difficult by the conventional system. A specific and rapid identification system based on sequences of internal transcribed spacer 1 of ribosomal DNA has therefore been developed. Using this system, we could identify two or more species mixed in the clinical samples.

Animals↗
PubMed2001

[Murine IgE antibody to recognize human major allergen, Mal f4].

To elucidate the specificity of murine IgE antibody against Malassezia furfur, the immunoblot patterns of IgE in sera obtained from mice inoculated repeatedly in the nasal cavity with M. f. cells, or injected intraperitoneally with M. f. cells mixed with Al (OH)3 gel were compared with those of IgE antibody detected in sera from patients with AD. Most of the murine IgE anti-Malassezia antibodies shared some antigenic bands with IgE in sera from patients with AD. The IgE antibody of murine also recognized Mal f4, one of the major allergens detected in patients with AD.

Allergens↗
PubMed2001

[A Case of central venous catheter-related infection with Malassezia sympodialis].

We report a 63-year-old male with central venous catheter-related infection caused by Malassezia sympodialis after total gastrectomy for a gastric cancer. He had fever and his leukocyte counts and C-reactive protein were elevated 14 days after his operation. After his central venous hyperalimentation catheter was removed, the inflammatory signs immediately disappeared, suggesting an intravenous catheter-related infection. A yeast-like fungus was cultured in brain-heart infection semi-solid agar ten days later, and was diagnosed morphologically as Malassezia sp. This strain was identified as M. sympodialis by Tween assimilation test and was confirmed by whole-sequence of internal transcribed spacer 1 regions (ITS1). This is the first report of catheter-related infection caused by M. sympodialis. This strain grew and was subcultured on CHROMagar Candida, potato dextrose agar and Sabouraud agar. There have been no reports of such a lipid-independent Malassezia sp. except for M. pachydermatis. The mechanism of lipid independence of this strain is undetermined and future work is needed. Malassezia sp. is receiving increased attention as an etiologic pathogen of catheter-related fungemia in clinical microbiology laboratories and infectious disease sections.

Catheterization, Central Venous↗
PubMed2001

Increased serum level of sialyl Lewis(x) antigen in blood from the tumor drainage vein in patients with non-polypoid growth type of colorectal cancer.

Two types of colorectal cancer with distinct morphologies have been described in recent studies: polypoid growth type (PG-type) and non-polypoid growth type (NPG-type). We hypothesize that the morphologic differences may correspond to additional biological distinctions. Ratios of sialyl Lewisa (CA 19-9), sialyl Lewisx (SLX), or carcinoembryonic antigen (CEA) in the venous blood drainage from the tumor to that of the respective antigen in the peripheral venous blood (d/p ratio) was examined in order to ascertain whether or not the ratio is correlated with either the PG-type or NPG-type colorectal tumor growth pattern. Blood samples from 118 patients with colorectal cancer were obtained from a peripheral vein and from the tumor drainage vein during surgical excision of the tumor. Statistical tests were conducted by univariate and multivariate (logistic regression) analyses. Among the cancers examined there were 17 PG-type (14.4%) and 101 NPG-type (85.6%). NPG-type cancers had a higher frequency of moderately differentiated adenocarcinoma cells and T3/T4 tumors than PG-type cancers (P<0.0001 and P<0.0001, respectively). NPG-type cancers had a more advanced stage than PG-type cancers (P=0.0007). The d/p ratio of SLX in NPG-type cancers was significantly higher than that in PG-type cancers (P=0.028). Multivariate logistic regression analysis showed that three variables, namely histologic type, T factor, and d/p ratio of SLX, were independently related to tumor growth patterns. In conclusion, NPG-type cancers are characterized by a high SLX d/p ratio, which may be at least partly responsible for a different tumor progression pattern compared to other cancer types.

Adenocarcinoma↗
PubMed2001

Diagnostic validity of computed tomography for mediastinitis after cardiac surgery.

BACKGROUND: Optimal treatment based on appropriate early diagnosis is essential in managing mediastinitis after cardiac surgery. We evaluated the accuracy of thoracic computerised tomography (CT) in the diagnosis of mediastinitis. METHODS: Forty-one patients in whom we performed CT after cardiac surgery were classified into two groups as follows; Six cases had mediastinitis requiring a redo surgical intervention (Group M). Thirty-five cases recovered without mediastinitis (Group C). Comparisons of CT findings in both groups were made retrospectively. RESULTS: In group M, CT and re-operations were performed 6.3+/-2.5 days and 8.0+/-5.2 days after previous operation, respectively. All but one of redo surgical procedures were mediastinal lavage and omental transplantation. Two patients died due to septic shock and multiple organ failure. CT in group M showed a soft tissue mass with contrast enhancement in 4 patients, bilateral pleural effusion in 5, free gas appearance in 4, and sternal dehiscence or destruction in 2 patients. Consequently, we regarded 4 of the 6 patients in this group as showing postoperative mediastinitis radiographically. In group C, CT performed 16.6+/-7.1 days after operations revealed findings suggestive of mediastinitis in 6 patients. Therefore, in terms of the validity of CT for the diagnosis of mediastinitis, the sensitivity was 67% and the specificity was 83%. CONCLUSION: The sensitivity of CT for diagnosis of mediastinitis after cardiac operations is unsatisfactory. Diagnosis by seeking infective changes in a multidisciplinary way is important in dealing with mediastinitis.

Aged↗
PubMed2001

Effects of T-588, a cognitive enhancer compound, on synaptic plasticity in the dentate gyrus of freely moving rats.

(1R)-1-benzo [b] thiophen-5-yl-2-[2-(diethylamino) ethoxy] ethan-1-ol hydrochloride (T-588) is a compound for the treatment of neurodegenerative disorders, including Alzheimer's disease and cerebrovascular diseases. T-588 reportedly alleviates learning and memory deficits in animal models of dementia. In the present study, we investigated the effects of T-588 on the induction and decay of long-term potentiation (LTP) and on the responses to paired-pulse (pp) stimulation in freely moving rats. Perforant path-evoked field potentials were recorded in the dentate gyrus by chronically implanted electrodes. LTP was induced by high-frequency stimulation 30 min after oral administration of T-588 (0.3 or 3 mg/kg). T-588 significantly augmented the increase in population spike amplitude and field excitatory postsynaptic potential slope after LTP induction. T-588 also prolonged the decay of augmented population spike amplitude, but had no significant effect on the response to pp stimulation. These results suggest that T-588 facilitates long-term synaptic plasticity, but not short-term synaptic plasticity in the dentate gyrus of freely moving rats. The effect of T-588 on long-term synaptic plasticity may contribute to the alleviation of learning and memory dysfunction seen in animal models.

Animals↗
PubMed2001

Preoperative serum levels of sialyl Lewis(a), sialyl Lewis(x), and sialyl Tn antigens as prognostic markers after curative resection for colorectal cancer.

In this study, we examined the preoperative serum levels of sialyl Lewisa, sialyl LewisX, sialyl Tn, and carcinoembryonic antigen in 243 colorectal cancer patients in order to clarify the role of these antigens as prognostic factors after curative surgery. The patients were divided into two groups: low and high antigen groups (lower and higher than a selected diagnostic-based cut-off value). Patients with high serum levels of sialyl Lewisa and carcinoembryonic antigen had shorter disease-free intervals than those with low serum levels of the respective antigen, although sialyl Lewisx and sialyl Tn showed no significant differences. Multivariate analysis revealed that three independent prognostic variables, including depth of tumor invasion, lymph node metastasis, and serum sialyl Lewisa level, did prove to have value in predicting disease-free interval. In conclusion, among the four antigens examined in this study, the preoperative serum level of sialyl Lewisa is the only independent prognostic variable for recurrence after curative resection of colorectal cancer.

Adult↗
PubMed2001

Dendritic cell vaccination with MAGE peptide is a novel therapeutic approach for gastrointestinal carcinomas.

The MAGE gene is selectively expressed in cancer tissues such as melanoma or gastrointestinal carcinomas, whereas no expression is observed in normal tissues except testis. There are several reports of successful induction of HLA class I-restricted antitumor CTLs using MAGE peptides, and some clinical trials with these immunogenic peptides were reported as effective for some patients with malignant melanoma. However, there are no similar studies in gastrointestinal carcinomas, which are important neoplasms. Autologous dendritic cells (DCs) were generated ex vivo and were pulsed with MAGE-3 peptide, depending on the patient's HLA haplotype (HLA-A2 or A24). Patients were immunized with DC pulsed with MAGE-3 peptide every 3 weeks at four times. Twelve patients with advanced gastrointestinal carcinoma (six stomach, three esophagus, and three colon) were treated, and no toxic side effects were observed. Peptide-specific CTL responses after vaccination were observed in four of eight patients. Improvement in performance status was recognized in four patients. Tumor markers decreased in seven patients. In addition, minor tumor regressions evidenced by imaging studies were seen in three patients. These results suggested that DC vaccination with MAGE-3 peptide is a safe and promising approach in the treatment of gastrointestinal carcinomas.

Aged↗