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Biomedical subjects

T Oka

Publications and source records attributed to T Oka.

At least 469 records · Page 26Linked to original sources
PubMed1996

[Clinical studies of inverted papilloma of the bladder].

Clinical studies were conducted on 9 cases of inverted papilloma of the urinary bladder which were transurethrally resected between August, 1987 and July, 1995 at our hospital, in males between 29 and 81 years of age (mean:58.3). Six of the 9 inverted papillomas were localized at the bladder neck and 3 in the trigone. Cystoscopic examinations revealed that inverted papillomas were divided into two types, one with a thick and short stalk with a smooth surface and the other with a thin and long stalk with/without a partial papillary surface. The majority of the former was located in the trigone and all of the latter cases in the bladder neck, suggesting that the two types occurred at different sites. Pathological examination by Hematoxylin-Eosin staining demonstrated that 5 of the 9 cases were of the trabecular type and 4 were of the grandlar type. Immunohistochemically, none of the tumors were stained with the antiprostatic-specific-antigen antibody revealed. Follow-up periods after the operation were from 12 to 48 months(mean:26.6 months) and no recurrence was observed.

Adult↗
PubMed1996

[Clinical problems in surgical treatment for active infective endocarditis].

From October, 1982, to December, 1995, 22 patients with active infective endocarditis underwent surgical treatment. Of 22 patients, 12 patients (group P) demonstrated microorganisms on blood culture obtained at the operation and/or in the excised valve, and 10 patients (group N) showed acute inflammatory reaction in the excised valve microscopically. Operative mortality in group P was significantly higher than that in group N (50% versus 0%,p < 0.01). Especially in group P, five of six patients (83%) with uncontorolled infection for more than eight days died within 30 days of operation. This showed that prolonged preoperative periods of uncontrolled infection influenced the surgical outcome of active infective endocarditis. In conclusion, patients who do not promptly response to antibiotic treatment must be considered for early operation within seven days of the diagnosis of infective endocarditis to decrease operative mortality. The plasma level of CRP and definition of sepsis may be useful as indicators of uncontrolled infection.

Adult↗
PubMed1996

Temperature-dependent cardioprotection of exogenous substrates in long-term heart preservation with continuous perfusion: twenty-four-hour preservation of isolated rat heart with St. Thomas' Hospital solution containing glucose, insulin, and aspartate.

BACKGROUND AND METHODS: Using an isolated working rat heart model, we determined the effects of glucose, insulin, and aspartate on recovery of cardiac function when used as components of preservation solution at different temperatures. After measurement of baseline cardiac function, hearts (n = 6 per group) were perfused with oxygenated St. Thomas' Hospital solution containing (1) vehicle, glucose (9 mmol/L) or aspartate (20 mmol/L) for 12 hours at either 20 degrees or 4 degrees C; (2) glucose or glucose + insulin (10 U/L) at 20 degrees C for 20 hours; and (3) glucose + insulin at 20 degrees C or glucose + insulin + aspartate at either 20 degrees or 4 degrees C for 24 hours. Cardiac function was measured after preservation and expressed as a percentage of baseline values. RESULTS: At 20 degrees C, both glucose and aspartate increased recovery of cardiac output (vehicle, 57.7% +/- 3.8%; glucose, 76.5% +/- 2.4% [p < 0.05 versus vehicle]; aspartate, 79.9% +/- 1.4% [p < 0.05 versus vehicle]). At 4 degrees C, glucose decreased recovery of cardiac output, whereas aspartate did not change the value (vehicle, 74.4% +/- 2.2%; glucose, 61.4% +/- 2.8% [p < 0.05 versus vehicle]; aspartate, 80.5% +/- 1.7%). The addition of insulin to glucose increased recovery of cardiac output (glucose, 24.6% +/- 4.0%; insulin + glucose, 69.2% +/- 2.0%: p < 0.05). The combined use of these three agents showed an additive effect in improvement of recovery of cardiac output at 20 degrees C (glucose + insulin, 64.2% +/- 2.2%; glucose + insulin + aspartate, 76.0% +/- 1.1%; p < 0.05), but the recovery at 4 degrees C (63.1% +/- 1.8%) was significantly lower than at 20 degrees C. CONCLUSIONS: These results suggest that glucose and aspartate afford differential cardioprotective effects depending on the temperature of the preservation solution and that combined use of glucose, insulin, and aspartate at the optimal temperature may extend graft preservation time.

Animals↗
PubMed1996

Expression of immunoreactive activin A protein in remodeling lesions associated with interstitial pulmonary fibrosis.

The expression of activin A, one of the transforming growth factor-beta supergene family, was studied in various pulmonary conditions associated with interstitial pulmonary fibrosis (3 cases with diffuse alveolar damage, 6 cases with idiopathic pulmonary fibrosis, and 1 case with pulmonary fibrosis associated with rheumatoid arthritis) using immunohistochemical techniques on paraffin-embedded sections. Controls consisted of 10 cases with normal pulmonary parenchyma, and 2 cases with primary pulmonary hypertension and 1 case with secondary pulmonary hypertension were also studied. The lung specimens from normal parenchyma weakly expressed immunoreactive activin A on the bronchiolar epithelium. In marked contrast, all of the specimens from cases with diffuse alveolar damage and interstitial pulmonary fibrosis demonstrated strong expression of activin A on metaplastic epithelium, hyperplastic smooth muscle cells, desquamated cells, and alveolar macrophages. Pulmonary arteries from patients with primary or secondary pulmonary hypertension showed abundant immunoreactive activin A on smooth muscle cells. These findings suggest a potential role for this growth factor, activin A, in the pathogenesis of pulmonary tissue remodeling associated with interstitial pulmonary fibrosis.

Activins↗
PubMed1996

[Detection of mutations in the CFTR gene using the PCR-dependent preferential homoduplex formation assay (PCR-PHFA) system].

A simple and efficient method for detecting DNA alterations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene has been developed using polymerase chain reaction dependent preferential homoduplex formation assay (PCR-PHFA). The technique is based on strand competition between a double labeled amplicon and an unlabeled amplicon during hybridization in a precisely controlled temperature gradient. By using this method the presence of single base substitutions in a PCR amplicon can be detected. In this report, experimental evaluation of the PCR-PHFA system in DNA analysis of exons of the CFTR gene with the highest frequency of most common disease-causing mutations is presented. The method was capable of detecting all mutations tested within the amplified regions of genomic DNA. PCR-PHFA can be used for mutation screening of CFTR and potentially other genes with a large number of reported mutations.

Cystic Fibrosis↗
PubMed1996

[Clinical treatment with cisplatin (CDDP) in pleural cavity for carcinomatous pleurisy--study of intraarterial concentration].

We investigated the intraarterial concentration of CDDP following continuous hyperthermic pleural perfusion (CHPP, 43 degrees C for 30 to 60 minutes) with 100 mg CDDP diluted in distilled water or saline in 6 lung cancers (2 pleural dissemination, 1 malignant pleural effusion, 3 positive wash cytology), 2 metastatic lung cancer (from breast cancer, 1 rhabdomyosarcoma with pleural dissemination), and 1 metastatic pleural tumor (adenocarcinoma, unknown origin). The level of CDDP was 9.16 to 24.1 micrograms/ml (average 16.1) in perfusion fluid, 0.3 after 5 minutes, 0.41 to 0.85 after 60 minutes and 0.15 to 0.27 (average 0.22) after 24 hours. There were no severe side effects nor any difference in effects by dilution fluid between distilled water and saline. Only 1 patient suffered pleural effusion after this treatment. The results suggested that CHPP with CDDP diluted by saline was effective for prevention and treatment of pleural dissemination.

Aged↗
PubMed1996

[The effect of continuous perfusion with St. Thomas' Hospital cardioplegic solution containing glucose, insulin and L-aspartate on functional recovery after myocardial preservation in the rat].

UNLABELLED: The aim of this study was to determine the effect of the continuous perfusion with St. Thomas' Hospital cardioplegic solution (ST solution) containing glucose, insulin and L-aspartate upon post-preservation recovery of cardiac function in the isolated rat heart. METHODS: Hearts from Wistar male rats were perfused with Krebs-Henseleit bicarbonate buffer (KHBB) solution and cardiac function was measured using an isolated working heart preparation. Hearts were then preserved by continuous perfusion, (1) with ST solution or ST solution containing L-aspartate (20 mmol/L9 at 20 degrees C and 4 degrees C for 12 hours, (2) with ST solution containing L-aspartate at 4 degrees C for 24 hours, (3) with ST solution containing glucose (9 mmol/L) and insulin (10 U/L solution) or ST solution containing glucose, insulin and L-aspartate at 20 degrees C for 24 hours. This was followed by 15 minutes of Langendorff perfusion and 20 minutes of working perfusion with KHBB solution. During the working perfusion in the post-preservation period, cardiac function was remeasured. RESULTS: (1) At 20 degrees C, percent recovery of cardiac output (%CO) was 57.7 +/- 3.8% and 79.9 +/- 1.4*% in the L-aspartate-free group and the L-aspartate-containing group, respectively (*p < 0.05). At 4 degrees C, %CO was 74.4 +/- 2.2% and 80.5 +/- 1.7% in the L-aspartate-free group and the L-aspartate-containing group, respectively (NS). (2) %CO in L-aspartate-containing group at 4 degrees C decreased to 46.8 +/- 2.4% when preservation time was extended to 24-hours from 12 hours. (3) On the other hands, the addition of L-aspartate to the ST solution containing glucose and insulin resulted in an additive protection and %CO was 76.0 +/- 1.1% even after 24 hour preservation at 20 degrees C. CONCLUSIONS: Our results indicate that L-aspartate as an additive to perfusion medium might be beneficial for myocardial preservation, and that at 20 degrees C, the addition of L-aspartate to the ST solution containing glucose and insulin could improve the post-preservation recovery after the 24-hour preservation.

Animals↗
PubMed1996

[Clinical studies on acute scrotum--focusing on torsion of the spermatic cord].

Surgical exploration was done on 50 patients with acute scrotum between June 1982 and October 1995. Of them, 24 (48%) had torsion of the spermatic cord, 9 (18%) had torsion of the appendage testis, 11 (22%) had intrascrotal hematoma, 4 (8%) had acute epididymitis, and 2 (4%) had bleeding of testicular tumor. The patients who had torsion of the spermatic cord were between 0 and 26 years of age (the mean: 14.6); 9 had torsion on the right side, and 15 on the left side. Infectious manifestations occurred in about 30%, and Prehn's sign developed in 37.5%. Of all cases, orchiopexy was performed in 10 cases and orchiectomy in 14. The testis was saved in 8 (88.9%) of the 9 patients who underwent surgery within 12 hours after onset. On the contrary, the testis was saved in only 2 (13.3%) of the 15 patients who underwent surgery more than 12 hours after onset. We concluded that early consultation, and exploration by a urologist are obligatory in the treatment of torsion of the spermatic cord.

Acute Disease↗
PubMed1996

[Outcome in patients with interstitial lung disease and polymyositis-dermatomyositis--a subgroup with poor prognosis].

To determine the role of interstitial lung disease (ILD) in the outcome of polymyositis-dermatomyositis (PM/DM), we studied 41 patients who had radiographic evidence of ILD among 51 patients with PM/DM. The patients were divided into 3 groups according to therapy: progressive, no change, or improved. Those classified as progressive had significantly higher rates of skin and lung symptoms, milder muscle symptoms, and lower levels of muscle enzymes than the other 2 groups, and none was positive for the anti-Jo-1 autoantibody. Nine patients with DM died of respiratory failure; they had low serum creatine kinase levels, no anti-Jo-1 antibodies, and a rapidly progressive course before death. Autopsy findings were obtained in 7 patients, and all had diffuse alveolar damage as the main pulmonary histological finding. A subgroup of patients with PM/DM-ILD have a poor prognosis, and ILD in PM/DM is an important prognostic factor.

Dermatomyositis↗
PubMed1996

[Importance of interstitial lung disease in collagen vascular disease: analysis of outcome].

We studied length of survival and related clinical findings in 715 inpatients with collagen-vascular diseases (1984 through 1994), the diagnostic Kaplan-Meier analysis showed that patients with polymyositis/dermatomyositis and those with systemic sclerosis did not survive as long as those with other types of collagen-vascular disease. Of the patients who died 37% died of respiratory failure due to interstitial lung disease. Patients with interstitial lung disease had better outcomes than did those with idiopathic interstitial pneumonia: they were younger, had higher initial vital capacities, and fewer episodes of acute exacerbation of lung disease than did those with idiopathic interstitial pneumonia. Among patients with interstitial lung disease, those who died of polymyositis/dermatomyositis did so within 1 year, but those who died of systemic sclerosis lived longer. Interstitial lung disease is an important prognostic factor in collagen-vascular disease, and needs further evaluation.

Cause of Death↗
PubMed1996

[Organ transplantation. 4. Renal transplantation].

Renal transplantation is well recognized as a better modality for improving quality of life (QOL) in patients with end stage renal disease as compared with hemodialysis. The better QOL attained by renal transplantation can be maintained as far as a renal allograft functions. The results of renal transplantation have been markedly improved mainly by introducing cyclosporine (CsA), especially using regimens in which a more decreased dose of CsA is used in combination with other immunosuppressive drugs, including azathiopurine and ALG to avoid nephrotoxicity of CsA. Mortality due to a variety of complications such as infections, hepatic failure, malignancy and cardiovascular diseases aggravates the results of renal transplantation. Although the result of Kidney transplantation in Japan is as good as that observed in European countries ane the United States, a number of transplantation performed in Japan is extremely small compared with these countries. In order to increase a number of renal transplantation in Japan, all efforts aiming at promoting cadaveric kidney donation should be performed as a first priority.

Humans↗
PubMed1995

Isolation and characterization of a novel perchloric acid-soluble protein inhibiting cell-free protein synthesis.

We found a novel protein in the postmitochondria supernatant fraction of rat liver, which is soluble in 5% perchloric acid and strongly inhibits protein synthesis in a rabbit reticulocyte lysate system. The protein extracted from the supernatant fraction with 5% perchloric acid was purified by ammonium sulfate fractionation and CM-Sephadex chromatography. The protein was shown to consist of two identical subunits with a molecular mass of 14 kDa. By immunoscreening with the rabbit antisera against the protein, a cDNA encoding the protein was cloned and sequenced. The cDNA contained an open reading frame of 411 base pairs encoding a 136-amino acid protein with a molecular mass of 14,149 Da. The deduced amino acid sequence was completely identical with that constructed from all of the above peptides. Interestingly, the perchloric acid-soluble protein inhibited cell-free protein synthesis in the rabbit reticulocyte lysate system in a different manner from RNase A. The protein is likely to inhibit an initiation stage of cell-free protein synthesis. Among the rat tissues tested, the protein was located only in liver and kidney. These findings are the first report on a new inhibitor that may be involved in the regulation of protein synthesis in those tissues.

Amino Acid Sequence↗
PubMed1995

The opposing effects of interleukin -1 beta microinjected into the preoptic hypothalamus and the ventromedial hypothalamus on nociceptive behavior in rats.

The effects of microinjections of recombinant human interleukin-1 beta (rhIL-1 beta) into the hypothalamus and neighboring basal forebrain on nociceptive behavior were studied using a hot-plate test in rats. The microinjection of rhIL-1 beta at doses between 5 pg/kg and 50 pg/kg into the medial part of the preoptic area (MPO) reduced the paw-withdrawal latency. The maximal reduction was obtained 30 min after the injection of rhIL-1 beta at 20 pg/kg. RhIL-1 beta (20 pg/kg)-induced hyperalgesia was completely blocked by the simultaneous injection of IL-1 receptor antagonist (IL-1ra, 20 ng/kg), Na salicylate (200 ng/kg) or alpha-melanocyte-stimulating hormone alpha-MSH, 20 ng/kg). The intra-MPO injection of rhIL-1 beta at doses of less than 5 pg/kg or more than 50 pg/kg (up to 2 ng/kg) into the paraventricular nucleus, the lateral hypothalamic area and the septal nucleus had no effect on nociception. The microinjection rhIL-1 beta (20 pg/kg-50 pg/kg) into the ventromedial hypothalamus produced a prolongation of the paw-withdrawal latency. A maximal prolongation was obtained 10 min after the injection of rhIL-1 beta at 50 pg/kg. This reaction was also blocked by the simultaneous injection of IL-1ra (50 ng/kg) and Na salicylate (500 ng/kg). These findings indicate that IL-1 beta in the MPO and the VMH produces hyperalgesia and analgesia, respectively, while, in addition, both effects are mediated by IL-1 receptors and the synthesis of prostaglandins.

Animals↗
PubMed1995

Histological and immunohistochemical analysis of lung development, with particular reference to lung hypoplasia.

Using immunohistochemical (IH) staining for epithelial membrane antigen (EMA), keratin, Leu-7, Ca 19-9, secretory component (SC) and surfactant protein A (SPA) on formalin-fixed, paraffin-embedded autopsy cases of stillbirth and early neonatal death, the normal profile of IH-positive cells in the airway of the developing fetal lung was clarified. IH-positive cells first appeared in the proximal region of the lung, and then in the distal region. Keratin-positive cells and EMA-positive cells were abundant at the 10th gestational week (10 GW), the earliest stage observed in this study. Cells positive for Leu-7 and Ca 19-9 appeared during the time when bronchial branches developed, and were abundant at around 16 GW, the time of completion of bronchial branching. On the other hand, SPA- and SC-positive cells appeared after the completion of bronchial branching, and were abundant around 29 GW and 34 GW, respectively. Acinous structural development was observed in terms of radial alveolar count (RAC). Cases of lung hypoplasia defined as a lung weight to body weight ratio of under 0.012 at > or = 28 GW or under 0.015 at < 28 GW showed a rather high tendency of abnormalities of cellular differentiation revealed by IH staining.

Bronchi↗
PubMed1995

Significance of Flow Cytometric DNA Analysis from Freshly Aspirated Samples.

The procedure of aspiration biopsy cytology by fine needle aspiration (ABC) is as option in establishing definitive diagnoses for breast cancers. In this series, a needle size of 21G was considered most suitable for ABC as well as flow cytometric DNA analysis. Histograms from fresh samples aspirated by fine needle clearly delineated a sharp peak in G&sup0;G(1) phases and also a better CV was obtained than with paraffin-embedded preparations. In addition, fresh samples gave more reliable DI and suggested the value of measuring nuclear DNA contents. It is believed that the prognoses of breast cancers are closely associated with DNA ploidy patterns. In this sense, flow cytometric DNA analysis of fresh samples of ABC is regarded as important in clinical use.

Journal Article↗
PubMed1995

The in vitro and in vivo resistance of synthetic enkephalin analogs to three enkephalin-hydrolyzing enzymes.

The magnitude of the in vitro and in vivo resistance of 3 synthetic enkephalin analogs, [D-Ala2,Met5]-enkephalin (DAME), [D-Ala2,Met5]-enkephalinamide (DAME-NH2) and [D-Ala2,D-Met5]enkephalin (DADME), to 3 enkephalin-hydrolyzing enzymes, amastatin-sensitive aminopeptidase (AsA), phosphoramidon-sensitive endopeptidase-24.11 (PsE) and captopril-sensitive dipeptidyl carboxypeptidase I (CsD), was estimated by comparing the potency of enkephalins in the absence of the peptidase inhibitor (PI) with that in the presence of the PI. The enhancement of the potency of enkephalins in the isolated mouse vas deferens preparation by 3 PIs, amastatin, phosphoramidon, and captopril, indicated that the resistance of enkephalins to AsA, PsE, or CsD was DADME [symbol: see text] DAME-NH2 [symbol: see text] DAME > [Met5]-enkephalin (ME), DADME > DAME-NH2 > DAME [symbol: see text] ME, or DADME [symbol: see text] DAME-NH2 > DAME > ME, respectively. Additionally, the data obtained by the s.c. administration of enkephalin analogs to 10-day-old rats with or without PI, showed that PsE played the most important role in the inactivation of both DAME and DAME-NH2. In addition to PsE, both AsA and CsD, or AsA alone, played the significant role in the inactivation of DAME, or DAME-NH2, respectively. In the inactivation of DADME, AsA alone played the significant role. These results showed that the 3 peptidases all played important roles in the inactivation of enkephalins, and therefore only an analog like DADME, which was quite resistant to the 3 enzymes, was able to produce the effect without PIs after its systemic administration. Since even DADME was not completely resistant to the 3 enzymes; however, its potency was further increased by pretreatment of infant rats with the PIs.

Aminopeptidases↗