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Biomedical subjects

Y Tada

Publications and source records attributed to Y Tada.

At least 271 records · Page 15Linked to original sources
PubMed1992

Infantile multilocular renal cyst.

A case of a Japanese 14-month-old male infant with multilocular renal cyst is presented. He was admitted with a chief complaint of an abdominal mass. Although clinically and radiographically multilocular renal cyst in the right kidney was suspected, total nephrectomy was performed because of extreme difficulty of partial nephrectomy and impossibility of complete neglect of malignant cystic tumor. Microscopically, immature glomeruloid tissue, primitive tubules, rhabdomyocytes and nerve fibers were noted. The histological diagnosis of multilocular renal cyst with partially differentiated dysplasia was made. Since the first report by Edmunds in 1892, the etiology of multilocular renal cyst has been discussed for years. In our present case, the pathologic findings suggest that multilocular cystic formation in the right kidney might be the result of developmental disturbances.

Humans↗
PubMed1992

Synthesis and regulation of the fourth component of complement (C4) in the human monocytic cell line U937: comparison with that of the third component of complement (C3).

Production of the fourth component of complement (C4) by the human monocytic cell line U937 and its regulation were investigated in comparison with the production of the third component of complement (C3) in a cell culture system. Although no detectable C4 was produced by U937 without stimulation, U937 was induced by recombinant interferon-gamma (IFN-gamma) to synthesize C4 in a dose- and time-dependent fashion. The production of C4 was reversibly inhibited by cycloheximide, indicating that it resulted from de novo synthesis. The C4 synthesized by U937 cells was functionally active as assessed by haemolytic assay. SDS-PAGE following biosynthetic labelling showed that subunit structure of C4 synthesized by U937 cells was identical with that of plasma C4 but that molecular weight of alpha-chain was greater than that of plasma C4. We compared the regulation of C4 synthesis with that of C3 synthesis. Although C3 synthesis by U937 cells was enhanced by IFN-gamma, lipopolysaccharide (LPS) and phorbol myristate acetate (PMA), C4 synthesis was induced only by IFN-gamma. LPS and IFN-gamma induced a synergistic increase in C3 synthesis by U937 cells. U937 cells incubated with LPS and IFN-gamma synthesized a greater amount of C4 than those incubated with IFN-gamma alone. Thus it was demonstrated that the synthesis of C3 and C4 was independently regulated. This study shows that the U937 cell line provides a useful model for studies on the synthesis of complement proteins and on the regulation of complement production.

Cell Line↗
PubMed1992

Leiomyosarcoma of the small intestine associated with von Recklinghausen's disease: report of a case.

A 54-year-old woman with intestinal multiple smooth muscle tumors including leiomyosarcoma, epithelioid leiomyoma, and leiomyomas in association with von Recklinghausen's disease is reported. Thirteen years after the excision of an intestinal leiomyosarcoma, another leiomyosarcoma arose in a different area of the jejunum and was also completely resected. Although leiomyomas are occasionally recognized in patients with von Recklinghausen's disease and a gastrointestinal neoplasm, there have been no other reports of leiomyosarcomas. Careful observation of the tumor is necessary and, if a rapid increase in tumor size is recognized, malignant tumor may have arisen and early surgical treatment is required.

Aortography↗
PubMed1991

Rapid isolation of a rice waxy sequence: a simple PCR method for the analysis of recombinant plasmids from intact Escherichia coli cells.

Polymerase chain reaction (PCR) is an efficient method for obtaining a desired nt sequence if both required primers can hybridize to the target DNA molecule specifically. A rapid and simple PCR-based method for analyzing plasmids using intact cells was established. An attempt to target a rice waxy sequence by PCR using homologous primers was also carried out. In three cases, specific fragments were amplified and their nucleotide sequences were determined. However, the cloned rice waxy gene contained base substitution mutations. The cumulative frequency of mutation after 30 polymerization cycles was estimated to be one in 500 bp.

Base Sequence↗
PubMed1991

Expression of a monocot LHCP promoter in transgenic rice.

The beta-glucuronidase (GUS) gene linked to the promoter of rice light harvesting chlorophyll a/b-binding protein of photosystem II (LHCPII) was introduced into rice by electroporation. Expression of the GUS gene with the LHCP promoter in transformed protoplasts and callus was much lower than with the cauliflower mosaic virus (CaMV) 35S promoter. In green organs, however, LHCP-GUS activity with the LHCP promoter was 10-fold higher than that with the CaMV 35S promoter. Expression of the LHCP-GUS gene was detected in leaves, stems and floral organs but not in roots. Histochemical analysis of leaves showed that the GUS gene was expressed specifically in green tissues. In selfed seeds of the transformants, GUS gene expression was detectable only in the germinated embryos after greening. Northern blot analysis revealed that transcription of the GUS gene with the LHCP promoter was not detectable in dark-grown seedlings of transformants but was induced by exposure to light. These results show that regulation of the introduced chimeric gene in transgenic plants was characteristic of the LHCP gene itself.

Blotting, Southern↗
PubMed1991

A new strategy for the reduction of acute myocardial infarction in variant angina.

To study the effects of stepwise early treatment in variant angina pectoris, frequencies of cardiac events and complications were examined after three different types of treatment. The subjects of the study consisted of 159 consecutive patients with variant angina pectoris, who were in need of hospitalization. The three treatment modalities were the introduction of calcium antagonists, nicorandil and nitroglycerin infusion, and percutaneous transluminal coronary angioplasty (PTCA), respectively. The cardiac event rate for this series of patients was 16% (25 of 159). The cumulative cardiac event rate was 22% at 1 year and 23% at 3 years in the first treatment period; 11% at the same intervals in the second treatment period; and 6% at the same intervals in the third treatment period. Our results suggest that it is important in the treatment of variant angina pectoris not only to prevent anginal attacks by the use of fast-acting coronary vasodilators, but also to initiate early revascularization.

Adult↗
PubMed1991

A defect in the protein kinase C system in T cells from patients with systemic lupus erythematosus.

To determine whether there is an intrinsic defect in T cells from patients with systemic lupus erythematosus (SLE), we studied signal transduction systems, assaying the total protein kinase C (PKC) levels and the phorbol myristate acetate (PMA)-induced activation of PKC in PHA-treated T cells. T cells from SLE patients showed a decrease in proliferation in response to PMA, but not to PHA, thereby suggesting the existence of an intrinsic abnormality in the PKC-mediated activation pathway. Total PKC activity in the T cells from SLE patients was significantly decreased. Although stimulation with PMA induced a translocation of PKC from the cytosol to the particulate fraction, translocated PKC activity after 2 nM PMA treatment was decreased in the SLE T cells. Furthermore, PMA-induced phosphorylation of 80-kDa substrates was also decreased in SLE T cells. These results suggest that there is a reduced PKC activity and an impaired PKC activation in response to PMA in the SLE T cells, a finding which may explain, if partially, the defect in T cell activation in patients with SLE.

Biological Transport, Active↗
PubMed1991

Ultrastructural localization of telencephalin, a telencephalon-specific membrane glycoprotein, in rabbit olfactory bulb.

Localization of a telencephalon-specific glycoprotein, telencephalin (TCLN), in the olfactory bulb of the rabbit was studied with an electron microscope. Anti-TCLN antisera appeared to stain plasma membrane, Golgi apparatus and multivesicular bodies of granule cells which are local circuit interneurons in the bulb. Principal neurons, mitral and tufted cells, were not immunoreactive. No glial cells showed immunoreactivity. Thus, expression of telencephalin is specific not only to the telencephalic segment of the brain, but also to the neuronal types.

Animals↗
PubMed1991

[Spheroplast formation in clinical isolates of gram-negative bacteria by beta-lactam antibiotic in the presence of Ca2+ or Mg2+].

Induction to cell wall-deficient bacteria has been suggested to be a cause of intractable and opportunistic infection after chemotherapy. Spheroplast formation by beta-lactam antibiotic in not so high osmotic pressure was investigated in six species of gram-negative bacteria. Some species of gram-negative bacteria were induced to form spheroplast at a high rate by 1:10 concentration of ceftizoxime in the presence of Ca2+ or Mg2+. Especially in 38% of Proteus mirabilis and P. vulgaris, more than 40% of the original cells were induced to form spheroplast by ceftizoxime in a medium supplemented with 40 mM Ca2+. The same formation rate was also found in 22% of Serratia marcescens. Formation rates in the drug sensitive strains of S. marcescens were enhanced as the drug concentration increased. Ca2+ was more effective in spheroplast formation than Mg2+.

Calcium↗
PubMed1991

[Herpes zoster in connective tissue diseases: II. Rheumatoid arthritis and mixed connective tissue disease in comparison with systemic lupus erythematosus].

We investigated the incidence of herpes zoster (HZ) and the immunological state to HZ in patients with rheumatoid arthritis (RA) and mixed connective tissue disease (MCTD) in comparison with systemic lupus erythematosus (SLE). HZ occurred in 6 (25%) out of 24 patients with RA and 4 (22%) out of 18 patients with MCTD. One patient had had HZ before the diagnosis of RA. On the other hand, all 4 patients with MCTD had had HZ before the diagnosis of MCTD. The patients with RA and MCTD showed normal or higher antibody titers to varicella zoster virus (VZV) than normal subjects as assayed by both complement fixation technique and neutralization test. However, the antibody levels were not very high compared to those in patients with SLE. On the other hand, only 7 (50%) of 14 patients with RA and 4 (40%) of 10 patients with MCTD showed positive skin reactions to VZV antigen, whereas all 15 normal subjects had positive reactions. Thus, cellular immunity to VZV was thought to be impaired in these diseases. In the patients who were receiving less than 10 mg/day of prednisolone, 7 (64%) of 11 had positive skin reactions in RA patients and 3 (60%) out of 5 patients with MCTD, whereas none (0%) out of 3 patients with RA and 1 (20%) out of 5 patients with MCTD who were receiving 10 mg/day or more prednisolone showed positive skin reactions. These results suggest that the high incidence of HZ in patients with RA and MCTD is probably due to an impaired cellular immunity as in the case of SLE.

Adult↗
PubMed1991

[Herpes zoster in connective tissue diseases: I. Association with systemic lupus erythematosus and its immunological abnormalities].

We determined the incidence of herpes zoster (HZ) in 119 patients with systemic lupus erythematosus (SLE). HZ occurred in 56 patients (47%), and 9 patients had had HZ even before SLE developed. After diagnosis of SLE, an incidence of zoster was high, 5.45 cases per 100 person-years. It was found that the susceptibility to HZ was not related to the presence of renal disorder or maximum dose of corticosteroids. The patients with SLE who had had HZ showed significantly higher antibody titers than those without a history of HZ and normal subjects as assayed by both complement fixation technique and neutralization test. On the other had, only 17 of 55 patients (31%) with SLE showed positive skin reactions to varicella zoster virus (VZV) antigen, whereas all 15 normal subjects had positive reactions. In the patients who were receiving less than 10 mg/day of prednisolone, 11 of 17 (65%) had positive skin reactions to VZV antigen, whereas only 4 of 31 (13%) patients who were receiving 10 mg/day or more prednisolone showed positive reactions. It was of interest that in 7 patients with SLE who had not received corticosteroids, only 2 (29%) patients showed positive skin reactions to VZV antigen. These results suggest that high incidence of HZ in patients with SLE is probably due to an impaired cellular immunity because of both underlying disease and corticosteroid treatment.

Adult↗
PubMed1991

Haemostatic factors associated with vascular thrombosis in patients with systemic lupus erythematosus and the lupus anticoagulant.

To elucidate the mechanism of vascular thrombosis in patients with systemic lupus erythematosus and the lupus anticoagulant changes in factors associated with haemostasis were investigated. The lupus anticoagulant was associated with an increased incidence of thrombosis, particularly cerebral thrombosis. Concentrations of fibrinopeptide A and fibrinopeptide B beta 15-42 were significantly raised in the plasma of patients with systemic lupus erythematosus and the anticoagulant compared with concentrations in patients without the lupus anticoagulant. The tendency towards formation of thrombosis was not found in all lupus patients with the anticoagulant, however. Concentrations of thromboxane B2 were remarkably raised in the plasma of the two patients with the lupus anticoagulant who had recently had thrombosis. Concentrations of 6-keto-prostaglandin F1 alpha, protein C, antithrombin III, and plasminogen were similar in both groups. No significant decrease in serum stimulatory activity on prostacyclin production by cultured aortic endothelial cells was noted in lupus patients with the anticoagulant, but inhibition was present in the two patients with recent thrombosis. These results indicate that although patients with the lupus anticoagulant are not always in a hypercoagulable state, haemostatic abnormalities found in some patients with the anticoagulant may be predictive of thrombotic events.

6-Ketoprostaglandin F1 alpha↗
PubMed1991

[Usefulness and limitation of immunotherapy of metastatic renal cell carcinoma with autologous lymphokine-activated killer cells and interleukin 2].

Fourteen patients with metastatic renal cell carcinoma (RCC) were treated by systemic administration of autologous lymphokine-activated killer (LAK) cells and interleukin-2 (IL-2). Pulmonary metastases alone were found in 9 cases, pulmonary and mediastinal nodal metastases in 3, and pulmonary and bone metastases in 2. LAK cells, generated by incubation in 2 units/ml of IL 2 for 3-4 days, were intravenously administered once or twice a week. In addition, beginning on the day of the first LAK cell infusion, 1000 units of IL 2 diluted in normal saline were intravenously infused once or twice a day with occasional supplementation of 1000 units of IL-2 on each day of LAK cell infusion. The total number of LAK cells and total amount of IL-2 administered per patient in this study ranged from 0.8 x 10(10) to 6.9 x 10(10) cells and from 3.3 x 10(4) to 21.4 x 10(4) units, respectively. As toxic effects caused by the infusion of LAK cells, headache, shaking chills, fever and leukocytosis were found in all 14 cases. Side effects possibly induced by IL-2 infusion were tolerable fever, fluid retention (body weight gain of 2-3 kg) and eosinophilia. No objective regression of mediastinal nodal or bone metastases was observed. In regard to lung metastases, however, partial and minor responses were observed in 3 and 2 cases, respectively. One of the 3 patients with a partial response was clinically free of disease after undergoing a thoracotomy for resection of residual lesions, but a brain metastasis was detected 10 months after the thoracotomy. The remaining 2 patients are being closely followed up at present. In 3 of 11 patients who showed a minor response, no change or progressive disease, brain metastases were observed during or after the immunotherapy. Furthermore, we examined the possibility of selection of suitable candidates for this therapy on the basis of the degree of in vitro LAK activity against autologous cultured tumor cells in 6 patients, but there was no significant correlation between in vitro autologous tumor cell lysis by LAK cells and the clinical response to immunotherapy. In conclusion, although a complete response could not be obtained, it can be said that this immunotherapy may be effective against RCC, in particular lung metastases, since a partial response was achieved in 3 of 14 patients. However, it should be taken into consideration that this immunotherapeutic approach may have a risk of increasing the frequency of brain metastases.

Adult↗
PubMed1991

Effect of serum treatment on pertussis antibody determination by ELISA.

Determination of anti-PT and anti-FHA antibodies by ELISA and neutralization titer by CHO-cell method were performed with inactivated and uninactivated human sera. The findings were as follows: in inactivated sera, higher anti-PT ELISA antibody titers were shown compared with the titers determined with corresponding inactivated sera, especially in sera having low ELISA antibody titers; however, anti-FHA ELISA antibody titers remained identical, with the uninactivated or inactivated sera. CHO-cell neutralization titer remained identical and stable between the uninactivated and inactivated sea. CHO-cell neutralization titers correlated with anti-PT ELISA antibody titers in sera without inactivation. Anti-PT ELISA antibody titers in inactivated sera, however, did not correlate with the corresponding CHO-cell neutralization titers. These results suggest the possible existence of (a) substance(s) with affinity to PT which enhance(s) the ELISA reaction when sera are inactivated. Therefore, the inactivation of sera is not favorable for anti-PT determination by ELISA.

Adhesins, Bacterial↗
PubMed1991

[Ectopic parathyroid adenoma: a case report].

A 69-year-old woman suffered from bilateral renal stones. Laboratory examinations showed primary hyperparathyroidism. Neck exploration including left hemithyroidectomy and partial thymectomy failed to reveal the abnormal parathyroid gland. Localization studies were done for an ectopic parathyroid adenoma. Repeated selective arteriography with digital subtraction technique revealed an ectopic parathyroid adenoma in the upper mediastinum. Computed tomography, ultrasonotomography and selective venous sampling also confirmed this finding. Subsequently, mediastinal exploration with partial sternotomy was performed and the ectopic parathyroid adenoma was removed. We discuss the preoperative localization studies for ectopic parathyroid adenoma.

Adenoma↗
PubMed1991

[A case of mitral stenosis developing infective endocarditis 18 months after PTMC].

We presented here a case of mitral stenosis developing infective endocarditis 18 months after PTMC. A 33-year-old male was admitted to our hospital for the evaluation of mitral stenosis with signs of congestive heart failure. The use of PTMC was adequately indicated based on the data of previous cardiac catheterization and was successfully performed. The post-operative clinical course was good leaving only slight mitral regurgitation demonstrated by post-valvuloplasty LVG. About 18 months after PTMC, the patient developed a high fever and erythema with tenderness on his leg, so he was admitted again. Blood culture was positive for streptococcus viridans. Moreover, echocardiogram revealed valvular vegetation on the anterior mitral leaflet, which is the characteristic finding of infective endocarditis. Antibiotics were so effective that his clinical course was relatively good with minor cerebral infarction during chemotherapy. Little is known about the prognosis and late complication of PTMC. However, our reported case may suggest that prophylactic chemotherapy might be recommended at least in some cases showing mitral regurgitation after PTMC.

Adult↗