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Biomedical subjects

J Kobayashi

Publications and source records attributed to J Kobayashi.

At least 397 records · Page 22Linked to original sources
PubMed1990

Isolation and characterization of the human hepatic lipase gene.

Overlapping bacterial phage and cosmid genomic clones were isolated spanning an area of approximately 60 kilobases that contains the human hepatic lipase (HL) gene. It is composed of 9 exons spanning approximately 35 kilobases of DNA. The entire coding regions, the 5'-flanking sequences, and the exon-intron junctions were sequenced. The intron positions correspond to those of human lipoprotein lipase and canine pancreatic lipase, supporting the concept that these genes constitute a dispersed gene family of lipases and have evolved by duplication of a common ancestral gene. A region of the HL gene, which displays a significant homology with various other lipolytic enzymes and contains the putative catalytic site serine residue of HL, was encoded by exon 4. A major transcription start site of the human HL gene was located by primer extension analysis, 43 nucleotides upstream of the translation initiation codon. Two possible promoter elements were located 25 and 63 nucleotides upstream of the transcription initiation site: a "TATA" box-like sequence, TAATA, and a sequence found in the promoter region of many liver-specific genes, AGGTTAATTATTAAT. In addition, sequences homologous to glucocorticoid and cAMP-responsive elements were identified in the 5'-nontranscribed region.

Amino Acid Sequence↗
PubMed1990

Pathological findings of the aortic homograft in a patient with tetralogy of Fallot twenty years after implantation.

We report pathological findings of the aortic homograft in a 27-year-old patient who died 20 years after implantation at the time of correction of tetralogy of Fallot. Although calcification of the homograft was severe with degeneration of valve leaflets, no functional obstruction of the homograft was found as a conduit. This observation may suggest a beneficial aspect of the aortic homograft as the right ventricle to the pulmonary artery conduit late after corrective surgery even if calcification was not avoided.

Adult↗
PubMed1990

Timing of operation for aortic regurgitation: relation to postoperative contractile state.

With angiography and pressure measurement, we determined left ventricular volume, wall stress, and systolic performance in 30 patients with aortic regurgitation before and after successful aortic valve replacement. End-systolic wall stress was greatly elevated preoperatively and decreased to normal postoperatively. Systolic pump performance assessed as ejection phase indexes was severely depressed preoperatively and improved to normal or near-normal postoperatively in most patients. The ratio of end-systolic wall stress to end-systolic volume index (ESS/ESVI), an index of myocardial contractility, was greatly decreased before operation. Postoperatively, the ratio increased in all patients, becoming normal in 12 of the 13 patients who had a preoperative ESS/ESVI of 2.9 or greater. However, 15 of 17 patients in whom the ESS/ESVI ratio was less than 2.9 still had subnormal ratios, which indicates the presence of irreversible contractile dysfunction. Stepwise multivariate analysis showed that preoperative ESS/ESVI was the only independent discriminator of postoperative normalization of the contractile function as assessed by ESS/ESVI. After aortic valve replacement, myocardial contractile state does not return to normal in a considerable number of patients. It is important to offer aortic valve replacement for aortic regurgitation before the chance for a good functional result is lost. The ESS/ESVI ratio may be a useful index in determining the timing of operation in patients with aortic regurgitation.

Adult↗
PubMed1990

Hand-made valved conduit with high-porosity knitted graft and glutaraldehyde-treated autologous pericardial trileaflet valve.

In 10 patients with various congenital heart defects requiring reconstruction of right ventricle to pulmonary artery continuity, a new hand-made valved conduit was introduced. To avoid late stenosis with peel formation of the graft, high-porosity Golaski knitted graft was chosen. The graft was sealed by fibrin glue, and autologous pericardium was treated with glutaraldehyde and used to construct a trileaflet valve inside the graft. This hand-made graft was pliable with good conformability. The valve function was found good in the intermediate follow-up in 8 patients. This composite valved conduit may be a good alternative to the xenograft valved conduit when allograft conduit is not available.

Bioprosthesis↗
PubMed1990

Effects of long-term treatment with probucol on serum lipoproteins in cases of familial hypercholesterolemia in the elderly.

The effect of probucol in lowering serum lipoprotein in young and middle-aged (YM) and elderly (E) patients with familial hypercholesterolemia were compared. Probucol at 1000 mg/day was administered orally to 37 YM patients and 14 E patients for an average of 10 months. Probucol treatment for this period caused significant reductions in the serum levels of total cholesterol, low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol, and apoprotein AI, AII, B, and CIII in both groups. The decreases in the levels of total cholesterol, LDL-C, and apoprotein B were greater in the E group than in the YM group (total cholesterol: YM, -19.3%, E, -31.3% [P less than .001]; LDL-C: YM, -17.0%, E, -35.4% [P less than .001]; apoprotein B: YM, -12.3%, E, -28.1% [P less than .01]). The decreases in other parameters in the two groups were not significantly different. The serum probucol concentrations in the YM and E groups were not significantly different. No significant side effects were observed in any patient. Thus probucol reduced the serum level of LDL more in the E group than in the YM group, and did so without any increase in the serum concentration of the drug or in side effects, suggesting that probucol is safe and beneficial for use in elderly patients.

Administration, Oral↗
PubMed1990

Lectin binding of rat gingival epithelia.

Oral gingival epithelium (OGE), oral sulcular epithelium (OSE) and junctional epithelium (JE) were examined histochemically by using different lectins as markers for epithelial differentiation. The staining pattern of gingival epithelia was compared with that of the buccal and palatal epithelia. Binding of WGA had a uniform distribution in all the epithelia examined. A positive reaction was found in all the basal and spinous layers, but not in the cornified layer of the epithelia. BPA binding was seen in the lower spinous layer of OGE, OSE, buccal and palatal epithelia, and in most of the JE. The basal layer and the cells directly attached to the tooth surface at the apical part of JE were nonreactive with BPA. GS-I reacted with the basal and suprabasal layers of each epithelium and with the cells attached to the tooth at the apical part of JE. UEA-I reacted with the upper spinous layer of OGE, OSE and epithelia of hard palate, but not with any of the cells of the JE. Our results agree with previous data suggesting that OGE and OSE exhibit squamous differentiation similar to that of the masticatory epithelium of hard palate. Furthermore, our results suggested that the JE cells undergo differentiation equivalent to that of the suprabasal and lower spinous cells of OGE. The cells along the tooth surface at the apical part of JE, however, form a distinct population of cells with basal nature.

Animals↗
PubMed1990

[Estimate of aztreonam (AZT) hydrolyzing enzymes from clinically isolated AZT-resistant gram-negative bacilli].

The MICs of Aztreonam (AZT) against 590 clinical isolates of Gram-negative bacilli were determined. About 13.4% (79 strains) of the isolates were AZT-resistant (MIC; 12.5 micrograms/ml less than or equal to). The resistance pattern against various beta-lactams and the effects on MICs of combination of Clavulanic acid (CVA) and AZT against AZT resistant strains suggested that AZT was inactivated by either type of IV (K1), Va (OXA1), or PSE2 beta-lactamases.

Aztreonam↗
PubMed1990

Left ventricular ejection performance, wall stress, and contractile state in aortic regurgitation before and after aortic valve replacement.

Left ventricular ejection performance, wall stress, and contractile state were evaluated in 35 patients with chronic aortic regurgitation. Cineangiography and pressure measurements were obtained before and a mean of 26 months after aortic valve replacement, and data were compared with those from 30 normal control subjects. The relation between quantitative changes in wall stress and changes in ejection fraction after surgery was determined. Preoperatively, end-systolic stress was elevated in patients with aortic regurgitation (218 +/- 45 vs. 160 +/- 23 kdynes/cm2 [mean +/- SD] for control subjects, p less than 0.01), and ejection fraction was depressed (0.46 +/- 0.11 vs. 0.65 +/- 0.05, p less than 0.01). End-systolic stress decreased postoperatively (151 +/- 41 kdynes/cm2, p less than 0.01) and ejection fraction increased (0.58 +/- 0.11, p less than 0.01). The magnitude of increase in ejection fraction correlated significantly and negatively (r = -0.65) with the quantitative change in end-systolic stress after surgery. Contractile function, as assessed by the ejection phase index-end-systolic stress relation, did not significantly change: 23 of 35 patients preoperatively and 18 of 35 patients postoperatively had values that clearly fell below the 95% confidence limit of the ejection fraction-end-systolic stress relation for controls. After surgery, individual ejection fraction-end-systolic stress relationships demonstrated a shift parallel to the regression curve for the control subjects. Moreover, persistent postoperative left ventricular hypertrophy was significantly associated with persistent contractile dysfunction. Thus, late improvement in left ventricular ejection performance after aortic valve replacement can be attributed to the reduction in end-systolic stress. Contractile function itself was not improved by surgery. Persistent postoperative hypertrophy may be a marker for myocardial contractile dysfunction.

Adolescent↗
PubMed1990

[Human mandibular movements during swallowing saliva. 2. Duration of swallowing saliva and that of tooth contact].

The sagittal incisal jaw movement during swallowing saliva was measured on 11 subjects (range: 24-30 years old) with "normal occlusion" by using a two-dimensional system applied infrared sensor. The duration of swallowing saliva and that of tooth contact were calculated with the program developed in our laboratory. The results obtained were as follows: 1. The average of the duration of swallowing saliva (T1) was approx. 3.5 sec on 11 subjects. 2. The average of the duration of tooth contact during swallowing saliva (T2) was approx. 2.1 sec on 11 subjects. Type Ia had the longest T2 (approx. 2.5 sec) among the types of tooth contact. 3. Type Ia had a greater ratio T2/T1 (74.4%) than those of the other types. In conclusion, it was clearly shown that the subject of type Ia had a longer duration of tooth contact during swallowing saliva than those of the other types in the absolute and relative values.

Adult↗
PubMed1990

[Combined effect of sulbactam/cefoperazone and other antibiotics against clinical isolates of multi-resistant strains. I. Effect of sulbactam against beta-lactams resistant strains and in vitro combined effect of sulbactam/cefoperazone with each of piperacillin, latamoxef, ceftazidime, fosfomycin and doxycycline].

We evaluated relationships between production of beta-lactamase and their resistances to beta-lactams, effect of sulbactam (SBT), a beta-lactamase inhibitor, against beta-lactam resistant strains, and combined effect of sulbactam/cefoperazone (SBT/CPZ) with other antibiotics against multi-resistant strains. Through these studies, we obtained the following results. 1. Most of the strains resistant to beta-lactams were beta-lactamase producers. 2. Relationships between the production of beta-lactamase and their resistances to beta-lactams indicate that their resistances generally were the highest in producers of both penicillinase (PCase) and cephalosporinase (CEPase), moderate in producers of either PCase or CEPase, and the lowest in beta-lactamase non-producers. Most of highly-resistant strains of MRSA appeared to be beta-lactamase non-producers though some exceptions were observed among methicillin-resistant Staphylococcus aureus (MRSA), Serratia marcescens and Pseudomonas aeruginosa. 3. SBT showed good effect against PCase producers, moderate effect against producers of both PCase and CEPase, little effect against CEPase producers, and no effect against beta-lactamase non-producers. 4. Results of combined effect of SBT/CPZ with other antibiotics indicated that good synergism was obtained by combining SBT/CPZ with fosfomycin (FOM) or piperacillin against multi-resistant strains of Proteus spp., Enterobacter cloacae, and S. marcescens, by combining SBT/CPZ with ceftazidime (CAZ) or FOM in methicillin-sensitive S. aureus and by combining SBT/CPZ with CAZ in P. aeruginosa. 5. Better synergism was obtained with the higher concentrations of antibiotics.

Anti-Bacterial Agents↗
PubMed1990

[Long-term evaluation after correction of tetralogy of Fallot].

The long-term survivors of the patients who underwent corrective surgery for tetralogy of Fallot between 1956 and 1988 were analyzed with respect to symptoms, late death, reoperation, and ventricular arrhythmias. For analysis, these 380 patients were separated into three periods, April 1956-December 1968 (Period 1), January 1968-May 1978 (Period 2), and June 1978-December 1988 (Period 3). In Period 3, the intracardiac procedures were performed with or without minimal right ventriculotomy. There were 24 late deaths (6.3%), and 10 of them were sudden. Nine patients (2.4%) required reoperation. Actuarial reoperation free survival rate was 93.8% at 10 years, 90.0% at 20 years, and 85.3% at 30 years. There were no differences in the actuarial curve between 3 periods though there was no late death in Period 3. NYHA functional class was I in 229 (80%) out of all 287 patients whose symptoms were clear to follow up, II in 50 (17), and III in 8 (3%). There was no patient in NYHA class IV. The incidence of NYHA class II and III was significantly higher in Period 1 (23%) and 2 (28%) than Period 3 (7%) (p less than 0.01, p less than 0.01). Ventricular arrhythmias were evaluated in 155 patients with ambulatory electrocardiography. Significant ventricular arrhythmias of Lown's grade 2 to 4 were detected in 52 patients (34%). The incidence of significant ventricular arrhythmias of Lown's grade 2 to 4 was significantly higher in Period 1 (50%) and 2 (53%) than Period 3 (15%) (p less than 0.01, p less than 0.01). Thus symptoms and ventricular arrhythmias increased when the follow-up interval exceeded 10 years or in patients with large ventriculotomy.

Actuarial Analysis↗
PubMed1990

[Subtotal cor triatrium with left partial anomalous pulmonary venous connection--successful correction in an infant].

This report concerns a 10-month-old infant with subtotal cor triatrium associated with left sided partial anomalous pulmonary venous connection to the innominate vein. In the operation, we found that the fossa ovalis existed between the right atrium and the accessory atrial chamber. We performed a radical operation which consisted of a resection of the intra-left-atrial diaphragma and a anastomosis of the vertical vein to the left atrium. His postoperative course was uneventful, and the result was satisfactory. We have presented and reviewed our case, and then discussed the embryogenesis and the hemodynamics. To our knowledge, our case represents the first successful surgical repair of this combination of defects in Japan.

Brachiocephalic Veins↗
PubMed1989

A case of neurofibroma located in the retroperitoneum involving the uncinate process of the pancreas.

A case of solitary neurofibroma in the retroperitoneum involving the uncinate process of the pancreas, which has been reported in only one case in Japan and less than 20 cases in the world literature, is described. A 57-year-old male complained of back pain and microhematuria. Plain and enhanced abdominal computed tomography (CT) indicated an 8 x 6 cm hypovascular tumor located in the uncinate process. We initially assumed it to be a cancer of the pancreas. His physical examination and blood chemistry result were normal. Various diagnostic imaging methods however, disclosed a rare type of tumor. The tumor was resected by pancreaticoduodenectomy and histological examination revealed it to be neurofibroma.

Humans↗
PubMed1989

Metabolism of LTC4 to LTD4 and LTE4 in isolated guinea pig lung lobes.

Leukotrienes are known to be easily metabolized to other substances. But the metabolic fates of LTC4 and LTD4 have not been established in the intact lung. In this investigation we perfused isolated guinea pig lung lobes and injected synthesized LTC4 and LTD4. The effluent was assayed by HPLC. LTD4 and LTE4 were detected following perfusion of LTC4, and LTE4 was detected following perfusion of LTD4. These results suggest that perfused guinea pig lung lobes may metabolize LTC4 to LTD4 and LTE4, and LTD4 to LTE4.

Animals↗
PubMed1989

Chemotactic factor generation and cell accumulation in acute lung injury induced by endotracheal acid instillation.

We studied the time course of chemotactic factor generation and inflammatory cell accumulation in the rabbit aspiration pneumonia model. Two major potent chemotactic factors, leukotriene B4 (LTB4) and C5a, in bronchoalveolar lavage fluid (BALF) were measured by radioimmunoassay, and cell analysis was also done. The level of LTB4 increased only in the early phase (2-6 h) after endotracheal acid instillation. The level of C5a increased gradually almost in parallel with the total protein level in BALF, and reached a maximum at 24 h. Neutrophil accumulation occurred early and reached a maximum at 24 h. In contrast, the number of alveolar macrophages increased from days 1 to 7. These findings suggest that the increases in LTB4 and C5a are responsible for accumulation of neutrophils and that C5a may be an important chemotactic factor for alveolar macrophage.

Animals↗
PubMed1989

Lipoprotein lipase with a defect in lipid interface recognition in a case with type I hyperlipidaemia.

Defective lipoprotein lipase (LpL) was found in the postheparin plasma (PHP) of a patient with severe hypertriglyceridaemia. The patient was a 14-year-old girl with a maximum plasma triglyceride (TG) level of 3600 mg d-1 who had been suffering from recurrent pancreatitis. The patient's LpL purified from the PHP by heparin-Sepharose and phenyl-Sepharose chromatographies hydrolysed tributryrin, but not triolein emulsified with Triton X-100 and phosphatidylcholine (PC), or in chylomicrons, whereas normal LpL hydrolysed these substrates. Moreover, unlike normal LpL, LpL from the patient did not associate with VLDL, as shown by Sepharose 4B column chromatography. The patient's LpL hydrolysed triolein emulsified with lysophospholipid at a normal rate in the presence of apolipoprotein CII. These findings suggest that this patient has LpL with a normal catalytic site for tributyrin but with a defect in lipid interface recognition resulting in loss of ability to recognize VLDL or chylomicrons, but not of triolein emulsified with lysophospholipid.

Adolescent↗