Biomedical subjects

N Abe

Publications and source records attributed to N Abe.

At least 73 records · Page 4Linked to original sources

PubMed1998

Monitoring of Echinococcus multilocularis infection in red foxes in Shiretoko, Japan, by coproantigen detection.

The study was conducted to evaluate a mAb-based coproantigen detection assay for monitoring fox prevalence of Echinococcus multilocularis infections in the Shiretoko National Park in Hokkaido, Japan. Eight fox families, each consisting of 2-4 adults and their pups, were selected because their territories have been determined. Faeces of each family (total n = 537) were collected monthly from April to October, 1994. Detection of coproantigen and taeniid eggs was recognized in 58 and 27 faeces, respectively, but mostly restricted in 1 family, in which coproantigen ELISA OD values had dual peaks, one in June and the other in October, whereas taeniid eggs were detected only from April to July. Fox pup faeces (n = 51) collected around the dens used by the positive family were all coproantigen and taeniid egg negative except for 1 faeces. These results suggest that the prevalence and infection pressure in the study area were low and the infected family terminated the infection in the summer and acquired a new one in the early autumn, 1994. This monitoring method for fox infection will be a practical management tool for E. multilocularis infection, especially at the tourist spots in Hokkaido where close contact of fox with humans is frequently observed.

Animals↗

PubMed1998

Biochemical and functional properties of lysine-specific cysteine proteinase (Lys-gingipain) as a virulence factor of Porphyromonas gingivalis in periodontal disease.

The oral anaerobic bacterium Porphyromonas gingivalis has been implicated as a major etiologic agent of progressive periodontal disease. A novel lysine-specific cysteine proteinase, termed "Lys-gingipain," was purified from the culture supernatant of the Arg-gingipain-deficient mutant of P. gingivalis (KDP112) by a simple method including immunoaffinity chromatography. The purified enzyme was found to be composed of a single polypeptide of Mr=51,000. Analysis of the enzymatic properties revealed several distinctive features of this enzyme. The proteolytic activity was remarkably activated by thiol-reducing agents and inhibited by idoacetamide, idoacetic acid, and leupeptin. The enzyme was also inhibited by the chloromethyl ketones of tosyl-L-lysine and tosyl-L-phenylalanine. However, internal protease inhibitors, such as cystatins and alpha1-antichymotrypsin, had no effect on the activity, suggesting its resistance to normal host defense systems in vivo. Despite its narrow specificity for synthetic substrates containing Lys in the P1 site, the enzyme extensively degraded human type I collagen and immunoglobulins G and A (both serum and secretory types). Most important, the enzyme was able to disrupt the functions of polymorphonuclear leukocytes, as shown by its inhibitory effect on the generation of active oxygen species from the activated cells. These results suggest that Lys-gingipain, like Arg-gingipain, plays a crucial role as a virulence factor from P. gingivalis in the development of periodontal disease via the direct destruction of periodontal tissue components and the disruption of normal host defense mechanisms.

Adhesins, Bacterial↗

PubMed1998

Pancreatic diabetes in Japan.

Pancreatic diabetes is usually a complication of other pancreatic disorders. Diabetes was a complication in 55.5% of 2,774 patients with chronic pancreatitis (CP) in Japan. More than half of alcoholic patients with CP in our clinic showed diabetes, and approximately 50% of those patients with diabetes were treated with insulin injections. On the other hand, cases of nonalcoholic CP showed mild endocrine dysfunction in terms of diabetic frequency and severity. Epidemiologic studies suggest that diabetes resulting from chronic pancreatitis accounts for <0.8% of all Japanese patients with diabetes. In patients with CP, B-cell dysfunction occurred first, followed by disturbances in A-cell function. Decreased insulin secretion during postprandial periods plays an important role in pancreatic diabetes. The fasting level of blood glucose is not useful for the diagnosis of the early stage of pancreatic diabetes. The glucose-tolerance test should be performed to diagnose early-stage diabetes in patients with CP with normal fasting blood glucose levels. For control of blood glucose in diabetic patients with CP, multiple injections of short-acting effective insulin before the meal are necessary. The incidence of long-term diabetic complications, diabetic retinopathy, nephropathy and neuropathy, in patients with CP with diabetes are not less than those in patients with primary diabetes.

Chronic Disease↗

PubMed1998

Evaluation of rheumatoid arthritis using a scoring system devised from magnetic resonance imaging of rheumatoid knees.

We studied the magnetic resonance imaging (MRI) of 120 knees in 86 rheumatoid arthritis (RA) patients and of 14 unaffected knees in 12 control cases. We also developed a scoring system as a quantitative analysis method. We divided the MRI into 10 items, and classified the severity of the symptoms into 4 grades (score 0 to 3). The average total score increased according to the radiographic grade. Soft tissue lesions were clearly detected, even in the early stages of RA. Items such as synovial proliferation showed a high score even in the early stages, suggesting that it was the initial symptom of RA. The score also showed a correlation with the inflammatory signs. These results suggest that this scoring system is very sensitive and yields a good reflection of RA activity. We demonstrated that this system is simple and convenient for routine diagnostic use. We further demonstrated that it is useful for following the advancement of RA and for evaluating the response to treatment.

Adult↗

PubMed1997

Prostaglandin E2 and IL-4 provide naive CD4+ T cells with distinct inhibitory signals for the priming of IFN-gamma production.

We investigated the effects of prostaglandin E2 and IL-4 on the acquisition of cytokine-producing ability by naive CD4(+) T cells in human umbilical cord blood. The presence of PGE2 or IL-4 at primary stimulation inhibited the production of IFN-gamma at secondary stimulation, and the combination of these stimuli resulted in cooperative effects. During primary stimulation with anti-CD3, the intracellular cAMP level was elevated in PGE2-treated cells but not in IL-4-treated or control cells. The signal provided by PGE2, but not by IL-4, was inhibited with RpcAMP, indicating that it was mediated by cAMP. After differentiation into Th2-like cells, cAMP levels in PGE2- and IL-4-treated cells were not different. Our results suggest that both PGE2 and IL-4 play important roles with distinct mechanisms in inhibiting the priming of IFN-gamma production of naive CD4(+) T cells.

CD4-Positive T-Lymphocytes↗

PubMed1997

Synthesis of a novel sialic acid derivative (sialylphospholipid) as an antirotaviral agent.

A novel sialylphospholipid (SPL) was synthesized from N-acetylneuraminic acid (NeuAc) and phosphatidylcholine (PC) by a chemical and enzymatic method and evaluated as an inhibitor of rotavirus. PC and 1,8-octanediol were conjugated by transesterification reaction of Streptomyces phospholipase D (PLD) under a water-chloroform biphasic system to afford phosphatidyloctanol, which was condensed with a protected 2-chloro-2-deoxyneuraminic acid derivative by using silver trifluoromethanesulfonate as an activator in chloroform and converted, after deprotection, to SPL. Rhesus monkey kidney cells (MA-104) were incubated with simian (SA-11 strain) and human (MO strain) rotaviruses in the presence of SPL, and the cells infected were detected indirectly with anti-rotavirus antibody. SPL showed dose dependent inhibition against both virus strains. The concentrations required for 50% inhibition (IC50) against SA-11 and MO were 4.35 and 16.1 microM, respectively, corresponding to 10(3)- and 10(4)-fold increases in inhibition as compared to monomeric NeuAc.

Animals↗

PubMed1997

Antibodies to glutamic acid decarboxylase in Japanese diabetic patients with secondary failure of oral hypoglycaemic therapy.

Some patients with non-insulin-dependent (Type 2) diabetes mellitus (NIDDM) are positive for antibodies to glutamic acid decarboxylase (anti-GAD), which have been shown to be a useful marker for the diagnosis and prediction of insulin-dependent (Type 1) diabetes mellitus (IDDM). Anti-GAD positive NIDDM patients tend to develop insulin deficiency. We investigated the prevalence of anti-GAD in 200 NIDDM with secondary failure of oral hypoglycaemic therapy (SF) and 200 NIDDM well controlled by diet and/or sulphonylurea agents (NSF). Twenty-two of 200 (11%, p < 0.05) SF patients and 6 of 200 (3%) NSF patients were anti-GAD positive. The positive. The positive rate for anti-GAD was as high as 23.8% in the non-obese and insulin deficient SF patients. The SF patients with anti-GAD tended to be non-obese and to have an impaired release of endogenous insulin. The internal before development of secondary failure was not associated with the presence of anti-GAD in this study. In conclusion we found that anti-GAD was positive in as many as 11% of the SF patients, suggesting that autoimmune mechanisms may play an important role in the pathogenesis of secondary failure or sulphonylurea therapy.

Analysis of Variance↗

PubMed1997

IL-7 induces proliferation, variable cytokine-producing ability and IL-2 responsiveness in naive CD4+ T-cells from human cord blood.

We investigated the effects of IL-7 on the proliferation and acquisition of cytokine-producing ability of naive CD4+ T-cells from human cord blood. Naive CD4+CD45RA+ T-cells from human cord blood expressed CDw127 (IL-7R) at higher levels than adult CD4+ CD45RA+ T-cells and produced IL-2 and a small amount of IFN-gamma upon stimulation with PMA and ionomycin. IL-7 induced IL-2-independent proliferation and both Th1- and Th2-type cytokine-producing abilities in cord blood CD4+CD45RA+ T-cells without stimulation via TCR. These results suggest that this IL-7-induced antigen-independent activation mechanism could contribute to maintaining the clonal size of naive T-cells with the potential to differentiate into either Th1 or Th2 cells at the sites of IL-7-expression.

Adult↗

PubMed1997

Effects of a novel potent aldose reductase inhibitor, GP-1447, on aldose reductase activity in vitro and on diabetic neuropathy and cataract formation in rats.

GP-1447 {3-[(4,5,7-trifluorobenzothiazol-2-yl) methyl]-5-methylphenylacetic acid}, a novel aldose reductase (AR) inhibitor, exhibited highly potent and specific inhibition of AR activity from human placenta, human muscle, porcine and rat lens with IC50 values ranging from 3 to 10 nM. Lineweaver-Burk plots revealed non-competitive inhibition between DL-glyceraldehyde or beta-NADPH and inhibition of AR by GP-1447. In contrast to epalrestat, AR activity inhibited by GP-1447 did not recover after dialysis for 24 hr. Administration of GP-1447 to streptozotocin (STZ)-induced diabetic rats for 5 days beginning 1 week after STZ injection effectively inhibited the accumulation of sorbitol in the sciatic nerve, lens and retina with ED50 values of 0.25, 1.6 and 2.9 mg/kg/day, respectively. The motor nerve conduction velocity (MCV) in STZ-induced diabetic rats was significantly decreased 4 weeks after the induction of diabetes. Treatment with GP-1447 for the following 2 weeks dose-dependently restored the decreased MCV with an ED50 value of 0.28 mg/kg/day. Administration of GP-1447 (3 and 15 mg/kg/day for 12 weeks beginning 3 days after STZ injection) completely prevented cataract formation and was accompanied by marked inhibition of sorbitol accumulation in the lens. Furthermore, partial reversibility of cataract formation and morphological changes of the lens was observed in diabetic rats treated with 15 mg/kg/day of GP-1447 for 5 weeks beginning 8 weeks after the induction of diabetes. From these results, GP-1447 would be expected to exert potent ameliorating effects on some diabetic complications. Potent inhibition of cataract formation will be one of the characteristics of this compound.

Aldehyde Reductase↗

PubMed1997

Purification and characterization of a dipeptidyl carboxypeptidase from Pseudomonas sp. WO24.

A dipeptidyl carboxypeptidase (DCP) activity was detected in cell-free extracts of Pseudomonas sp. WO24. After purification and characterization the enzyme was found to be homogeneous by SDS-PAGE, and had a molecular mass of 74,000 Da by SDS-PAGE and 72,000 Da by gel filtration, indicating that it is monomeric. The isoelectric point was 5.2 and optimum pH was 6.5-7.0. It showed a specific activity of 780 mumol/min/mg, which is the highest of the values shown by known enzymes. The enzyme hydrolyzed angiotensin I to angiotensin II and sequentially released Phe-Arg and Ser-Pro from the C-terminus bradykinin. The DCP could not cleave imido-bonds, Gly-Gly bonds, or tripeptides. The enzymatic activity was completely inhibited by 0.001 mM EDTA and 0.1 mM O-phenanthroline, but it was not affected by general serine and cysteine protease inhibitors. Addition of Zn2+ completely restored the original activity of the inactivated DCP treated with EDTA. These results suggest that this enzyme is a zinc metalloprotease. The characteristics of the purified enzyme are slightly different from those of the DCPs from Escherichia coli, Pseudomonas maltophilia, and Corynebacterium equi, and considerably from those of the DCP from Bacillus pumilus.

Amino Acid Sequence↗

PubMed1997

Prevalence of Toxocara spp. eggs in sandpits of parks in Osaka city, Japan, with notes on the prevention of egg contamination by fence construction.

Toxocara spp. eggs were detected from 30 (75%) out of 40 sandpits of parks, in Osaka city. This prevalence was higher compared to those reported other areas of Japan. Since we examined a large quantity of sample, this could have resulted to higher prevalence. The number of eggs recovered decreased following fence construction around sandpits, but it did not sufficiently prevent the contamination of eggs. Improvement of fence design and education of sandpit users are necessary when contemplating fence construction around sandpits as a measure against contamination with Toxocara spp. eggs.

Animals↗

PubMed1997

[One-stage-bilateral adrenalectomy by thoracoabdominal approach for bilateral large pheochromocytomas in men type IIa. A case report].

We experienced a case of MEN type 2a with bilateral and large pheochromocytomas. A 39-year-old man was admitted to the previous hospital with complaints of paroxysmal headache. hypertension and diabetes mellitus. Radiographic imagings showed thyroid tumors in both lobes and bilateral adrenal tumors. Thyroid tumors were histologically proved to be medullary thyroid carcinoma by needle biopsy and systemic investigations revealed an excessive secretion of plasma and urinary cathecholamines which suggested the presence of pheochromocytoma. The patient was diagnosed as MEN type 2a. He was admitted to our hospital for the treatment of bilateral adrenal tumors for which we performed one-stage bilateral adrenalectomy by thoracoabdmonal approach. Both adrenal tumors were histologically confirmed as pheochromocytoma. The patient's postoperative course was uneventful. He underwent uneventful total thyroidectomy approximately 2 months after bilateral adrenalectomy. Even in bilateral and large pheochromocytomas, one-stage bilateral adrenarectomyenables safe postoperative managements. We concluded that the thoracoabdominal approach is feasible in the patients with huge and cranially spreading adrenal tumor, which gives us a wide operative field for easy vascular control.

Adrenal Gland Neoplasms↗

PubMed1997

[A case of supramediastinal neurinoma: its operative approach (via supraclavicular route) and radiographic findings (target sign)].

A 76-year-old female with supramediastinal tumor was admitted. CT scan showed central high density area surrounded by low density area and MR imaging emphasized the same concentric circle. This concentric circle pattern on CT scan and MR imaging is called "Target sign", which is known as characteristic radiographic finding of neurinoma. Therefore we could diagnose her case as mediastinal neurinoma preoperatively. She underwent operation through the supraclavicular approach and the tumor was completely resected. By incising the skin through the modified left hemi-collar incisional line and cutting the clavicula at its central part, we could ensure a good operative field and safely performed this operation without mid-sternotomy or thoracotomy. The supraclavicular approach for the operation of supramediastinal tumor is useful.

Aged↗

PubMed1997

[A study of the association between the aortic pulse wave velocity and atherosclerotic risk factors among Japanese Americans in Seattle, U.S.A].

Cardiovascular disease prevention screening was conducted among 1389 Japanese Americans in Seattle, Washington, U.S.A. from 1989 to 1994. The association between atherosclerotic risk factors and the aortic pulse wave velocity (PWV), an indicator of atherosclerosis, was examined by using multiple logistic regression method. Based on a study in 1996 by Suzuki et al. on the association between PWV and atherosclerotic indicators, abnormally high PWV was defined as 8.0 m/sec. and over for those less than 60 years of age and 9.0 m/sec. and over for those 60 years of age and older Significant odds ratios to estimate the risk for the presence of abnormally high PWV were found in age >or= 60 years (4.31, p < 0.001), hypertension (2.00, p < 0.001), diabetes (5.65, p < 0.001), current drinker (0.44, p < 0.001), ex-drinker (0.49, p < 0.05), and ex-smoker (1.82, p < 0.01) among men. Women showed a similar association: age > or = 60 years (3.03, p < 0.001), hypertension (1.94, p < 0.01), diabetes (2.47, p < 0.05), TC/HDL-C >or= 4.5 (1.98, p < 0.001), current drinker (0.47, p < 0.001), and ex-drinker (0.45, p < 0.05). Our findings are almost identical to those from other studies showing the association between coronary heart disease and its risk factors. The question of whether PWV can be a predictor of atherosclerotic diseases, particularly coronary heart disease, remains to be answered by additional studies. However, PWV may serve as a simple and valuable indicator to estimate the extent and severity of asymptomatic atherosclerosis in the large artery.

Alcohol Drinking↗

PubMed1996

Mosaic structures of neurotoxins produced from Clostridium botulinum types C and D organisms.

We isolated the gene encoding a botulinum neurotoxin (BoNT) of 1285 amino acids with a molecular weight of 147,364 from the toxigenic bacteriophage d-sA of Clostridium botulinum type D strain South African (Dsa). The BoNT of Dsa (BoNT/Dsa) is composed of three regions on the basis of the homology to BoNT types C1 (BoNT/C1) and D (BoNT/D). The N-terminal (Met-1 to Val-522) and the C-terminal regions (Trp-945 to Glu-1285) have high identity to corresponding regions of BoNT/D (96% identity) and BoNT/C1 (74% identity), respectively. The core region (Pro-523 to Lys-944) is common to three toxins (83% to 92% identity). These results suggest that neurotoxins produced from Clostridium botulinum types C and D are composed in a mosaic-like fashion.

Amino Acid Sequence↗

PubMed1996

Differential expressions of collagen types IV, III, and I during the development of invasive trophoblasts in rats.

We examined the differential expressions of collagen types IV, III and I in the developing feto-maternal placental tissue of pregnant rats by a combination of in situ hybridization and immunohistochemistry. At day 9.5 of gestation, polygonal invasive cytotrophoblasts from the ectoplacental cone, which was modifying the maternal central artery, revealed intensely expressed alpha 1 (IV) and alpha 1 (III) collagen mRNAs. The localization patterns of these translated products, collagen type IV and procollagen type III, were slightly different in the invasive cytotrophoblasts. Collagen type IV densely deposited intracellularly and intercellularly in the maternal central artery and in the thickened basement membranes of the cytotrophoblasts. However, expression of alpha 1 (I) collagen mRnA and procollagen type I was hardly detectable in the cytotrophoblasts. At day 13 of gestation, a high level of alpha 1 (IV) collagen mRNA was expressed in the cytotrophoblastic cell layer (trophospongium) and in the invasive large cytotrophoblasts. A moderate level of alpha 1 (III) collagen mRNA was also expressed mainly in the cytotrophoblasts, while alpha 1 (I) collagen mRNA was expressed at very low levels. Interestingly, procollagen type III failed to show linear immunoreactivity in the subepithelial extracellular matrix beneath the maternal artery with the invasive cytotrophoblasts. Additional quantitative analyses of these type IV, III, and I collagen mRNA levels in in situ hybridization experiments between several cell types also revealed significant differences individually. Electron-microscopic study detected no cross-striated collagen fibers in the thickened basement membrane-like structures adjacent to the invasive cytotrophoblasts. Fibrillar and basement membrane collagen gene expressions, their protein syntheses, and the processing of these procollagens seems to be developmentally regulated in the invasive cytotrophoblasts during the organization of feto-maternal placental tissue. The remodeling of the maternal central artery by the invasive cytotrophoblasts is important for ensuring the adequate blood supply to the developing placenta and fetus.

Animals↗

PubMed1996

Evaluation of wound healing of the teat with and without low level laser therapy in dairy cattle by laser Doppler flowmetry in comparison with histopathology, tensiometry and hydroxyproline analysis.

Perforated teat wounds in eight lactating Holstein-Friesian cows were closed by four suture patterns with or without low level laser therapy (LLLT). Wound healing was evaluated by laser Doppler flowmetry (LDF), tensiometry and hydroxyproline analysis, and compared with histopathological examination. The three-layer pattern provided the best healing of the entire teat. Mucosal hyperplasia was observed in Gambee and continuous two-layer pattern while eversion of the skin, presence of suture tracts and a greater amount of granulation tissue were observed with the continuous and interrupted two-layer patterns. The epidermis in LLLT groups more closely resembled the normal epidermis, and collagen fibres were denser, thicker and better arranged in LLLT than in non-LLLT groups. LDF, tensiometry and hydroxyproline analysis correlated well with histopathological examination. The results suggest that LDF, a more rapid, less invasive and painless procedure, can replace tensile strength measurement or hydroxyproline analysis to assess the progress of teat wound healing.

Animals↗

PubMed1996

Histopathological effect of low-level laser therapy on sutured wounds of the teat in dairy cattle.

Perforating wounds were made on the cranial surface of 32 teats in eight dairy cattle. The teats were distributed into eight groups with four kinds of suture patterns. The used suture patterns were Gambee in Groups A and E, continuous 2-layer (Cushing for submucosal layer, continuous horizontal mattress for intermediate layer and skin) in Groups B and F, separated 2-layer (simple continuous for mucosal layer, vertical mattress for intermediate layer and skin) in Groups C and G, and 3-layer (simple continuous for mucosal and intermediate layers, simple interrupted for skin) in Groups D and H. The wounds of Groups E, F, G and H were subjected to 3.64 J/cm2 dose of low-level laser, using a helium-neon system with an output of 8.5 mW, continuous wave at 632.8 nm. Histopathologically, healing was different between various suture patterns and between low level laser therapy (LLLT) and non-LLLT-groups. The results suggest that the 3-layer pattern was the best and LLLT could accelerate healing of perforating wounds of the teat in dairy cattle.

Animals↗