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Biomedical subjects

Y Yano

Publications and source records attributed to Y Yano.

At least 127 records · Page 7Linked to original sources

Serum levels of tumor necrosis factor-alpha are increased in obese patients with noninsulin-dependent diabetes mellitus.

To clarify the significance of the serum levels of tumor necrosis factor-alpha (TNF-alpha) in the mechanism of insulin resistance, we studied 12 obese patients with noninsulin-dependent diabetes mellitus (NIDDM). We evaluated the relationship of TNF-alpha levels with the visceral, subcutaneous, and total fat areas measured by computed tomography (CT), and with insulin resistance evaluated by the glucose infusion rate (GIR) observed during an euglycemic hyperinsulinemic clamp study. Controls consisted of 12 normal subjects and 12 nonobese patients with NIDDM. TNF-alpha levels were measured using a high sensitivity enzyme-linked immunosorbent assay. Following admission, all patients with NIDDM participated in a 4-week program of diet and exercise. After this treatment, we evaluated the relationship of the serum levels of TNF-alpha with the area of body fat, the GIR, and the resultant change in the TNF-alpha level. Serum levels of TNF-alpha in the obese patients with NIDDM significantly exceeded those observed in normal subjects (P < 0.01) or in the nonobese patients with NIDDM (P < 0.01). Serum levels of TNF-alpha in obese NIDDM patients showed a significant positive correlation with the area of visceral fat before (r = 0.662, P < 0.03) and after (r = 0.508, P < 0.05) the treatment; similar correlation was observed in all patients with NIDDM before (r = 0.537, P < 0.02) and after (r = 0.430, P < 0.05) the treatment. Serum levels of TNF-alpha in obese NIDDM patients showed a significant negative correlation with GIR after the treatment (r = -0.595, P < 0.05). Serum levels of TNF-alpha were significantly reduced in the obese patients with NIDDM after the treatment (P < 0.01), while those in the nonobese NIDDM patients were unchanged. These results suggest that serum TNF-alpha levels may play an important role in mechanism of insulin resistance associated with obesity.

Adipose Tissue↗

Significant decreased insulin secretion in a diabetic patient with clinically probable multiple sclerosis.

A 39-year-old man with chief complaints of aphasia, disorientation and acalculia was admitted to our hospital. He was diagnosed as a clinically probable case of multiple sclerosis (MS) and his symptoms improved while on steroid pulse therapy. The patient had been diagnosed as having diabetes mellitus 16 years before the onset of MS and his insulin secretion further decreased with time. Slight insulin resistance was observed during a euglycemic hyperinsulinemic clamp study. These results suggested that this patient developed diabetes mellitus mainly due to the decrease of insulin secretion.

Adrenal Cortex Hormones↗

[Saponins in Bupleurum smithii Wolff var. parvifolium Shan et Y. Li].

Five saikosaponins and two saikosapogenins were isolated from the roots of Bupleurum smithii var. parvifolium by column chromatography, preparative-TLC and HPLC, and identified as saikosaponin a, saikosaponin d, saikosaponin b2, saikosaponin b4, chikusaikoside I, saikogenin F and saikogenin G on the basis of spectral analysis. All of them were isolated from this plant for the first time.

Bupleurum↗

[A case of submitral left ventricular pseudoaneurysm following mitral valve replacement for infective endocarditis].

A 25-year-old female presented with high fever and dyspnea. She was diagnosed as infective endocarditis, severe mitral regurgitation, grade II A-V block and acute left heart failure We performed emergency mitral valve replacement. At operation, mitral ring abscess was found which was extended to submitral left ventricular wall. The abscess was excised and the defect of mitral annulus was repaired with Xenomedica patch. Left ventriography at 30 days after the operation showed a submitral left ventricular pseudoaneurysm (size: 30 x 26 x 33 mm) without evidence of infection. Further examinations showed that the aneurysm extended to the annulus of tricuspid valve through interatrial septum. About 1 year after the operation, she had paroxysmal atrial fibrillation due to right atrial overloading. We decided to perform reoperation. At reoperation, the ostium of the aneurysm was closed with a Xenomedica patch after taking off the prosthetic valve. It was very difficult to close the ostium because we could not see the submitral ventricular wall directly. Although postoperative course was good, she had complete A-V block necessitating permanent pacemaker.

Adult↗

[Type A acute aortic dissection: late reoperations for dilatation of the distal false lumen and aortic regurgitation].

From January 1990 to December 1996, 71 patients aged 33 to 79 years (mean 60 +/- 11) underwent an emergency operation for type A acute aortic dissection. Fifty-three (74.6%) survived, and were followed 7 to 94 months (mean follow up 2.9 +/- 1.8 years) after the first operation. Five patients underwent reoperation for dilatation of the distal false lumen 7 to 52 months (mean period, 25 months) after primary repair. One patient underwent replacement of the arch and descending aorta, three patients underwent replacement of the descending aorta, and one patient underwent the stented graft implantation, resulting in closure of the entry site. Three patients underwent reoperation for severe aortic valve regurgitation 12 to 31 months (mean period, 24 months) after primary repair. Two patients underwent aortic valve replacement, and one patient underwent aortic root replacement. The actuarial freedom from reoperations was 81 +/- 6.9% at 3 years, and 73 +/- 9.9% at 5 years.

Adult↗

Identification of mu-, m-calpains and calpastatin and capture of mu-calpain activation in endothelial cells.

The presence of the calpain-calpastatin system in human umbilical vein endothelial cells (HUVEC) was investigated by means of ion exchange chromatography, Western blot analysis, and Northern blot analysis. On DEAE anion exchange chromatography, calpain and calpastatin activities were eluted at approximately 0.30 M and 0.15-0.25 M NaCl, respectively. For half-maximal activity, the protease required 800 microM Ca2+, comparable to the Ca2+ requirement of m-calpain. By Western blot analysis, the large subunit of mu-calpain (80 kDa) was found to be eluted with calpastatin (110 kDa). Both the large subunit of m-calpain (80 kDa) and calpastatin were detected in the respective active fractions. By Northern blot analysis, mRNAs for large subunits of mu- and m-calpains were detected in single bands, each corresponding to approximately 3.5 Kb. Calpastatin mRNA was observed in two bands corresponding to approximately 3.8 and 2.6 Kb. Furthermore, the activation of mu-calpain in HUVEC by a calcium ionophore was examined, using an antibody specifically recognizing an autolytic intermediate form of mu-calpain large subunit (78 kDa). Both talin and filamin of HUVEC were proteolyzed in a calcium-dependent manner, and the reactions were inhibited by calpeptin, a cell-permeable calpain specific inhibitor. Proteolysis of the cytoskeleton was preceded by the appearance of the autolytic intermediate form of mu-calpain, while the fully autolyzed postautolysis form of mu-calpain (76 kDa) remained below detectable levels at all time points examined. These results indicate that the calpain-calpastatin system is present in human endothelial cells and that mu-calpain may be involved in endothelial cell function mediated by Ca2+ via the limited proteolysis of various proteins.

Antibody Specificity↗