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J Kato

Publications and source records attributed to J Kato.

At least 469 records · Page 26Linked to original sources
PubMed1989

Genetic analyses of processing involving C-terminal cleavage in penicillin-binding protein 3 of Escherichia coli.

The processing of Escherichia coli penicillin-binding protein 3 (PBP 3) was investigated by gene manipulation for producing hybrid and truncated PBP 3 molecules. The hybrid PBP 3 was processed when the N-terminal 40 residues of PBP 3 were replaced by the murein lipoprotein signal peptide which lacked the cysteine residue for processing and followed by seven extra linker residues. In contrast, the PBP 3 molecules truncated at Thr-560 (28-residue deletion) or at Thr-497 (91-residue deletion) were not processed, and those truncated at Phe-576 (12-residue deletion) were processed at a greatly reduced rate. The results indicate that the C-terminal part, rather than the N-terminal part, is involved in the processing. This was supported by the result that the purified mature PBP 3 retained the complete N-terminal sequence with Met for translation initiation. The cleavage at the C-terminal region was shown by the loss of [35S]cysteine label when the cysteine-free hybrid PBP 3 joined to a cysteine-rich extra peptide tail was processed into the mature form. Confirmative assays for processing of PBP 3 were aided by a newly found prc mutant, defective in the processing involving the C-terminal region. A plasmid that directs PBP 3 truncated at Thr-560 complemented a thermosensitive PBP 3 mutation, but the truncated product was unstable in vivo. This suggests the importance of C-terminal hydrophobic regions that terminate at Leu-558 to PBP 3 functioning and the requirement of further-distal peptides for the stability of PBP 3.

Acyltransferases↗
PubMed1989

Characterization of partially activated p60c-src in chicken embryo fibroblasts.

Previous studies identified the amino acid changes involved in the activation of p60c-src and revealed that the activation accompanies an alteration of its tyrosine-phosphorylation site. We show here that p60c-src that had been converted to transforming protein by amino acid substitution of the c-src gene either at position 63, 95 and 96, or 338 (J. Kato, T. Takeya, C. Grandori, H. Iba, J. B. Levy, and H. Hanafusa, Mol. Cell. Biol. 6:4155-4160, 1986) and encoded in a Rous sarcoma virus variant was phosphorylated on both Tyr-416 and Tyr-527 in chicken embryo fibroblasts. The results obtained from protease V8 analysis, tryptic peptide mapping, and fractionation with nonionic detergent indicated that the p60 of each variant was present in two forms in the population of the virus-infected cells; one was phosphorylated on Tyr-416, and the other was phosphorylated on Tyr-527. On the other hand, colonies isolated in soft agar contained exclusively p60 of which only Tyr-416 was phosphorylated. These results implied that the limited population of p60 was activated in these Rous sarcoma virus variant-infected chicken embryo fibroblasts and that the activated p60 was concentrated in transformed cells. Furthermore, these two forms of p60 differed in their affinity for the detergent-insoluble cellular matrix in spite of their identical primary amino acid sequences, suggesting that the effect of alteration of the tyrosine phosphorylation site was coupled with the degree of stability of this association.

Animals↗
PubMed1989

Effects of antiserum against alpha-rat atrial natriuretic polypeptide in spontaneously hypertensive rats.

To clarify the physiological role of endogenous atrial natriuretic polypeptide (ANP), we investigated the effects of specific rabbit antiserum against alpha-rat ANP (alpha-rANP) on hemodynamics, diuresis, and natriuresis in spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats (WKY). Intravenous administration of anti-alpha-rANP antiserum caused an obvious rise of mean blood pressure and cardiac output in both SHR and WKY compared with rats administered with normal rabbit serum. Although there was no significant difference in increments of mean blood pressure between SHR and WKY, the increment of cardiac output in SHR was significantly higher than that in WKY. On the other hand, significant reductions in urine output and urinary sodium and potassium excretion lasted for approximately 20 min after administration of the antiserum in both SHR and WKY compared with rats administered with normal rabbit serum. There was no significant difference in these initial maximal decrements between SHR and WKY. These results indicate that endogenous ANP has an important physiological role in the regulation of hemodynamics and water-electrolyte balance in both SHR and WKY. The greater increment of cardiac output in SHR in response to the antiserum suggests that endogenous ANP in SHR may have a stronger cardiosuppressive action that it does in WKY.

Animals↗
PubMed1989

[A clinical study and the diagnosis in magnetic resonance imaging of renal scarring].

Twenty-nine kidneys of seventeen patients (nine boys and eight girls) with vesicoureteral reflux and repeated urinary tract infection were studied by magnetic resonance imaging for diagnosis of renal scarring and correlation between clinical data and the degree renal scarring. Renal scarring is classified into three types according to findings in magnetic resonance imaging. The degree of renal scarring are classified into five grades according to traditional grading of intravenous pyelogram. If a fine deformity of calyx is shown on intravenous pyelogram, magnetic resonance imaging demonstrates renal scarring. Magnetic resonance imaging without irradiation is exceedingly valuable for the diagnosis of renal scarring. The appearances of magnetic resonance imaging were supported by X-ray computed tomography. There is a substantial correlation between serum creatinine and the grades of renal scarring by magnetic resonance imaging. There is a substantial correlation between fever attacks and the grade of renal scarring, and there is a significant reverse correlation between the age of the onset of upper urinary tract infection and the grade of renal scarring. It is suggested that upper urinary tract infection is the most significant factor in scar formation.

Adolescent↗
PubMed1989

[A study on accumulation of cholesterol in rat prostate].

An experimental model of prostatic hypertrophy was created by freezing the urethra at the opening of the ventral prostate in rats and administering a cholesterol-rich diet to induce cholesterol accumulation. Four-week-old Fisher rats were divided into a control group, a cholesterol-rich diet group (by adding 1% cholesterol to the diet), a frozen group, and a frozen and cholesterol-rich diet group, and were reared for 5 months. The animals were killed, and the ventral prostate was removed, weighed, and the lipid was extracted. Cholesterol content was measured by an enzymatic method. A cholesterol-rich diet without freezing had no effects on the ventral prostate, and after freezing alone, the weight of the prostate was smaller than that of the control group. However, in the group cholesterol-rich diet after urethral freezing, the cholesterol content per mg of tissue increased. This indicates that cholesterol accumulation can be induced in the prostate by administering a cholesterol-rich diet after creating the proper secretory disturbance.

Animals↗
PubMed1989

[Evaluation of epithesis by others].

The present study aims at recognizing how maxillofacial prostheses prepared by us for out patients are evaluated by persons in contact with them. Questionnaire was sent to 158 persons (125 fifth year students of The Nippon Dental University, School of Dentistry at Niigata, 17 dental hygienists and nurses and 12 hospital clerical employees). The following results were obtained: 1) Upon seeing a maxillofacial defective patient momentarily, 91.8% of the answers regarded his inserted maxillofacial prostheses as agreeable. 2) Upon being opposite to such a patient without conversation for a comparatively long time, 18.3 and 80.4% of the answers regarded his covering the defective part with gauze and his inserted maxillofacial prostheses, respectively as agreeable. 3) Upon conversing with such a patient, 86.1 and 9.5% of the answers regarded his inserted maxillofacial prostheses and his covering the defective part with gauze, respectively as agreeable. 4) In the case of close relatives of such a patient, 67.7, 20.3 and 5.7% regarded his inserted maxillofacial prostheses, his covering the defective part with gauze and his leaving the defective part as it is, respectively, as agreeable. 5) With respect to the facial aesthetics of the case presented as one of reference, 42.7, 15.9 and 13.3% pointed out mandibular deviation, ocular prostheses and condition of contact of the maxillofacial prostheses with the skin, respectively, to be unnatural.

Esthetics↗
PubMed1989

[Clinical significance of serum acid soluble glycoproteins (ASP) and immunosuppressive acidic protein (IAP) in inflammatory diseases and liver diseases].

In order to study the clinical significance of ASP and IAP, we have measured serum concentration of ASP and IAP in 259 patients with inflammatory diseases, non-inflammatory diseases, autoimmune diseases and liver diseases. Significantly higher correlation (coefficient of correlation = 0.922) was found between ASP and IAP. There were good correlation between ASP, IAP levels and erythrocyte sedimentation rate (ESR), C-reactive protein (CRP). Coefficient of correlation were 0.705 and 0.673 between ESR and ASP, IAP; 0.621 and 0.623 between CRP and ASP,IAP, respectively. There were food correlations between ASP levels and thrombo test (TT) and hepaplastin test (HPT). The positive rate and mean concentration of ASP, IAP in patients with inflammatory diseases were significantly higher than noninflammatory diseases. It is suggested that serum ASP, IAP could be one of the useful indicator for evaluating the clinical course of patients with inflammatory diseases. Serum concentration of ASP, IAP in patients with chronic liver diseases were lower than normal subjects, especially serum levels in patients with decompensated liver cirrhosis and chronic hepatitis (active) were significantly lower than normal subjects. In patients with hepatoma with cirrhosis, serum levels of ASP, IAP were significantly lower than the hepatoma patients without cirrhosis. The determination of ASP, IAP in liver diseases seems to be useful for evaluating the severity of diseases, the effects of therapy and the forecast of prognosis.

Autoimmune Diseases↗
PubMed1989

[Study on renal osteodystrophy using 2-compartment model analysis of bone scintigraphy. 1. Clinical significance of K Index].

The dynamic analyses of bone scintigraphy were performed in 30 cases of hemodialysed patients. The regression analyses between biochemical data or duration and K indexes obtained from the 2-compartment model analysis in the maxillofacial region were carried out. The obtained results were as follows. 1) The duration and K indexes were significantly correlated with 1 or 2% of significance level in the parietal bone and the zygomatic bone. 2) Serum Ca and K indexes were highly correlated in every settled ROI. The correlation coefficients were distributed from 0.58 to 0.79. In the cranial bone the correlation were more higher than in maxilla and mandibular bone. 3) Serum ALP and K indexes have more higher significant level of correlation than the results of Ca. The correlation coefficients were distributed from 0.48 to 0.83. The level of significance were changed by location. The highest correlation coefficient was 0.83 in the parietal bone. 4) Serum c-PTH and K indexes have significant correlation in every settled ROI with the correlation coefficient from 0.59 to 0.69. The significance level were nearly equal in every location. 5) In the case of subtotal parathyroidoectomy the K indexes which were abnormally high in preoperation showed the tendancy to decrease toward normal range in postoperation. These results indicated that K indexes reflected the bone change caused by renal osteodystrophy. And the K indexes considered to be usefull to estimate the bone improvement.

Bone and Bones↗
PubMed1989

[Anatomical and histological studies on a microdontic wisdom tooth].

The purpose of this study is to investigate features and histological structures of the microdontic wisdom tooth. Materials investigated in this study deal with a very small upper right microdontic wisdom tooth of a male patient aged thirty-six. It was observed with binocular microscopy and under X-ray. Horizontal ground sections of it were prepared and observed with polarizing microscopy, phase microscopy, microradiograph, and scanning electron microscopy. Total length of this specimen was about 1/2 of the average measurement in Japanese upper third molars, breadth of the crown about 1/3, thickness of the crown about 1/4. It had one cusp and one root. It is considered that one cusp was formed by fusing of the mesiolingual cusp and mesiobuccal one because fundamental features of the buccal and lingual surfaces of upper molars were preserved in this specimen. It is thought that dental tubules in this specimen were formed more densely than those in the common wisdom tooth because the space of retreating odontoblasts of this specimen was limited but that enamel rods in this specimen were formed more thickly than those in the common wisdom tooth because the space of retreating ameloblasts of this specimen was wide. It is considered that the degeneration in this specimen came up to not only the dental form, but also the histological structure of the enamel because the surface layer of the enamel of this specimen was composed of the laminal structure.

Adult↗
PubMed1989

[Clinicopathological study on multiple primary malignant neoplasms, related to the oral-maxillofacial region].

The present study consists of a clinical and histopathological analysis of those cases which were diagnosed as multiple primary malignant neoplasms of the oral-maxillofacial region and the other organs. 9 patients of those multiple primary malignant neoplasms out of 261 patients of malignant neoplasms in the oral-maxillofacial region, who visited in out department from 1975 to 1986, were detected. 3.4% of the incidence rate was calculated. All the cases were male, and these included each 1 case of triple and quadruple. 7 cases were detected prior in the oral-maxillofacial region to the other organs. There seemed to be a preponderance to early detection of a neoplasm in the oral-maxillofacial region. Therefore, the possibility of multiple primary malignant neoplasms should be kept in mind in the routine clinical activities. 2 cases were synchronous, 6 months or less interval between the first and the second neoplasms, the others were metachronous, averaged 5-year interval. The primary sites in the oral-maxillofacial region were tongue (3 cases), floor of the mouth (2), buccal mucosa (2), lower gingiva (1), maxillary sinus (1), all of them were diagnosed as squamous cell carcinomas, histopathologically. The other organs were esophagus (3 cases), stomach (2), colon (2), lung (2), liver (1), urinary bladder (1), hypopharynx (1). Histopathological diagnoses of them were squamous cell carcinomas (3 cases of esophagus, each 1 case of lung, urinary bladder, and hypopharynx), adenocarcinomas (2 cases of stomach and colon, and 1 case of lung), and a hepatoma. It's necessary to differentiate the multiple primary malignant neoplasms from metastases when each of them were diagnosed as squamous cell carcinomas.(ABSTRACT TRUNCATED AT 250 WORDS)

Head and Neck Neoplasms↗
PubMed1989

Plasma concentration and renal effect of human atrial natriuretic peptide in nephrotic syndrome.

To elucidate the pathophysiological role of atrial natriuretic peptide (ANP) in nephrotic syndrome, the plasma level of ANP and renal response to exogenous human alpha-ANP (alpha-hANP) were measured in untreated adult patients with idiopathic nephrotic syndrome (NS) and compared with those of normal volunteers (NL). The plasma concentration of immunoreactive ANP (ir-ANP) in NS (112 +/- 9.8 pg/ml, n = 9, mean +/- SE) was not significantly different from that in NL (98 +/- 8.0 pg/ml, n = 13). However, a significant positive correlation was observed between the plasma ir-ANP level and blood volume in NS (r = 0.714, p less than 0.05). In an infusion study with synthetic alpha-hANP (25 to 100 ng/kg/min), the urine flow rate increased from 0.67 +/- 0.08 to 7.11 +/- 1.08 ml/min in NL (n = 5, p less than 0.01) and from 0.64 +/- 0.16 to 2.88 +/- 0.70 ml/min in NS (n = 9, p less than 0.05) and the urinary sodium excretion increased from 115 +/- 16 to 466 +/- 62 microEq/min in NL (p less than 0.01) and from 51 +/- 8 to 207 +/- 58 microEq/min in NS (p less than 0.01). The absolute and percent changes in urine flow rate and the absolute change in sodium excretion were lower in NS (p less than 0.05) than in NL. The percent change in sodium excretion in NS did not differ from that in NL. In 2 patients with high plasma ir-ANP concentrations, however, infusion of ANP induced poor sodium excretion (59 and 95 microEq/min at 100 ng/kg/min ANP infusion, respectively). Hemodynamic and renal parameters such as blood pressure, pulse rate and creatinine clearance were similarly affected in both NL and NS. We also found that the urinary excretion of protein was significantly increased in NS (p less than 0.05) during infusion of alpha-hANP. Our data suggest that the plasma level of ir-ANP is regulated by blood volume status, and that the renal responsiveness to ANP, at least in part, contributes to water and sodium retention in NS.

Adult↗
PubMed1989

[Clinico-statistical study of medical complication in dental patients].

Eight hundred and fifty two cases, who were introduced from the Dental Hospital to Department of Internal medicine, Medical Hospital at Niigata, The Nippon Dental University, were examined for medical complications. About one hundred and fifty cases were introduced per year from the Dental Hospital, which consisted of about 15% of the total outpatients in the Department of Internal medicine. The age distribution showed a high incidence of patients in their 50's. The number of patients over 60 years old was 220 (25.8%), and the number of patients over 65 years old was 160 (18.8%). There was then a high percentage of elder patients. The reason for the initial medical examinations was the need for a pre-operative medical examination in 42.6% of the total cases. Concerning medical complications among the patients, the highest incidence was hypertension in 116 cases (13.6%); the second highest was hepato-biliary and pancreatic diseases in 114 cases (13.4%); and heart diseases in 81 cases (9.5%). Eighteen cases of HBs antigen positive (2.1%) were seen among the patients with liver diseases. Among those with blood diseases, anemia showed the highest incidence, and a small number had leukemia and hemophilia. Diabetes mellitus showed up in 39 cases (4.6%), most of them being more than 40 years of age. Mentally and physically handicapped patients accounted for 30 cases. Half of them were from the pre-operative examination area, like tooth extraction.

Aged↗
PubMed1989

[A case of pulmonary neurilemmoma].

Intrapulmonary or bronchial neurilemmoma are rare neoplasms and there have been only 29 cases reported in the foreign and domestic literature. We experienced a case of neurilemmoma of the right upper lobe in a 41-year-old male. The patient had no complaint but, a small coin lesion (1.2 x 1.4 cm) was pointed out by chest X-ray examination. The tumor was diagnosed as neurilemmoma by transbronchial lung biopsy and a right upper lobectomy was performed. He has remained asymptomatic in the 18 months after operation.

Adult↗
PubMed1989

[Two cases of B-cell lymphoma occurring in a mother and her daughter at the same time].

Many cases of familial aggregation of lymphoproliferative malignancy have been reported. But familial aggregation of non-Hodgkin lymphoma is less frequent than Hodgkin's disease, Burkitt's lymphoma, and adult T-cell leukemia. Here we report familial B-cell lymphomas occurring in a mother and her daughter at the same time. The daughter (43 years old) was admitted because of fever. She died of a rapidly progressive neurological disturbance. The mother (75 years old) was admitted because of fever and pleural effusion, and then died with a complication of cryoglobulinemia. The histological findings of their lymph nodes revealed diffuse lymphoma, medium-sized cell type, with B-cell phenotype and mixture of cleaved and non-cleaved nuclei. They had no common chromosome abnormalities, while they shared HLA-A 2, B 35, and Cw 3 antigen. Viral infection was not identified, by routine serological test and electronmicroscopic study.

Adult↗
PubMed1988

Free and bound forms of atrial natriuretic peptide (ANP) in rat plasma: preferential increase of free ANP in spontaneously hypertensive rats (SHR) and stroke-prone SHR (SHRSP).

Free and bound forms of atrial natriuretic peptide (ANP) in rat plasma were analysed by gel permeation chromatography combined with a radioimmunoassay (RIA) for rat ANP (rANP). Gel permeation chromatography showed two immunoreactive peaks in rat plasma, one corresponding to alpha-rANP, rANP(99-126), and the other eluted at a high molecular weight, clearly different from gamma-rANP, rANP(1-126). The chromatographic profile of rat plasma after incubation with synthetic alpha-rANP demonstrated that the high molecular immunoreactivity had ANP-binding capacity. This bound form of ANP was almost totally excluded following extraction procedure, therefore, the immunoreactive ANP (ir-ANP) measured with the extraction assay was mainly free ANP. On the other hand, direct RIA may detect not only the free but also the bound form of ANP. Using both direct RIA and the extraction method, bound forms of plasma ANP in spontaneously hypertensive rats (SHR) and stroke-prone SHR (SHRSP) were compared to normotensive Wistar Kyoto rats (WKY). Bound forms of plasma ANP in 20-week-old SHR and SHRSP were significantly higher than that in age-matched WKY. The ratio of free/bound form of plasma ANP in SHR and SHRSP also significantly increased compared to WKY, indicating a preferential increase in free ANP in the plasma of these hypertensive rats. These findings suggest that a bound form of ANP may be present in rat plasma and that it may play some pathophysiological role in the hypertension of SHR and SHRSP. Increased free ANP in plasma may indicate a compensatory increase in ANP release in these hypertensive rats.

Animals↗