Search PubMed⌕ Search

Biomedical subjects

T Oka

Publications and source records attributed to T Oka.

At least 847 records · Page 47Linked to original sources
PubMed1990

Medical and surgical complications of renal transplantation: diagnosis and management.

Renal transplantation is a common modality of therapy in end-stage renal failure, but it has the potential of developing many complications, both surgical and medical in nature. In transplantation surgery, more than in any other type of surgery, prevention of these complications is essential. This includes attention to many details, including optimum organ salvage, preservation, implantation, and postoperative care. Although infection has decreased in frequency and severity with the advent of antiviral and antibacterial agents, prevention, early diagnosis, and suitable treatment with appropriate antibiotic(s) will be necessary to obtain desirable results and to reduce morbidity and mortality. It should be stressed that although careful attention to the patients and adjustment of the immunosuppressive regimen may mitigate much of the gastrointestinal, hematologic, and osteogenic complications, high incidence of cancer of the skin and mucous membrane continues.

Bacterial Infections↗
PubMed1990

Transfection of beta-casein chimeric gene and hormonal induction of its expression in primary murine mammary epithelial cells.

To study the regulatory sequence elements responsible for casein gene expression, we constructed a chimeric gene containing 5.3 kilobases (kb) of the 5'-flanking sequence and 1.6 kb of the 3'-flanking sequence of the mouse beta-casein gene fused to the bacterial chloramphenicol acetyl-transferase (CAT) gene. The chimeric gene was transfected by the calcium phosphate-precipitation procedure into primary mouse mammary epithelial cells prepared from pregnant mice. The transfection procedure had negligible effect on expression of the endogenous beta-casein gene. Expression of the beta-casein-CAT chimeric gene required the synergistic actions of insulin, hydrocortisone, and prolactin. Expression of the chimeric gene also depended on the appropriate substratum because the degree of hormonal induction of the chimeric gene was much higher in cells cultured on a reconstituted basement membrane (Matrigel) than in cells cultured on either type I collagen gel or plastic. On the other hand, the expression of a simian virus 40-CAT chimeric gene in which the CAT gene was driven by the early promoter of the virus was not influenced by the hormonal milieu and occurred at the highest level in cells cultured on plastic. Additional transfection experiments with a series of beta-casein-CAT constructs suggested the existence of regulatory elements responsible for hormonal induction and negative regulatory elements.

Animals↗
PubMed1990

Large cell carcinoma of the lung. Prognostic implications of histopathologic and immunohistochemical subtyping.

Fifty-four patients with large cell carcinoma of the lung were treated surgically, and the prognostic factors were examined histologically and immunohistochemically. Based on evidence of intercellular cohesion, as seen in the histologic results, the patients were placed into two subtypes, compact growth type and louse structure type. The survival rates were 46% and 28% at five years, respectively (P less than 0.05). Immunohistochemically, keratin, epithelial membrane antigen (EMA), secretory component, lactoferrin, and carcinoembryonic antigen (CEA), as histologic markers of epithelial differentiation, were detectable in large cell carcinoma of both types and more frequently in the compact growth type than in the loose structure type. The difference was significant in case of detection of keratin, EMA, and CEA (P less than 0.05). These observations suggest that a large cell carcinoma may differentiate into an adenocarcinoma or squamous cell carcinoma. The presence of intercellular cohesion and use of these markers reflect prognosis of the disease.

Adult↗
PubMed1990

The effects of perioperative portal venous inoculation with donor lymphocytes on renal allograft survival in the rat. I. Specific prolongation of donor grafts and suppressor factor in the serum.

In order to investigate the in vivo functional role of the liver in the immune responses in organ transplantation, effects of perioperative portal venous p.v. administration of donor lymphocytes on renal allograft survival were tested in the rat kidney transplant model. Donor lymphocytes were prepared from BN (BN, RT-1n) or third-party DA (RT1a) rat spleens and lymph nodes and injected p.v. or intravenously to Lewis (LEW, RT-1l) hosts on the day of transplantation (day 0). Untreated LEW hosts rejected BN renal grafts at 7.8 +/- 0.6 days (n = 10). Intravenous administration of 1 x 10(8) BN cells to LEW hosts on day 0 caused a slight, but not significant, prolongation of renal allograft survival (MST = 9.5 +/- 3.0 days, n = 13, NS), whereas portal venous inoculation of 1 x 10(8) BN cells on day 0 remarkably prolonged renal graft survival to 22.2 +/- 5.3 (n = 10, P less than 0.01). The prolongation of graft survival was antigen-specific; the administration of 1 x 10(8) DA cells p.v. to LEW hosts did not prolong the survival of BN renal grafts (MST = 7.4 +/- 0.8, n = 5). Spleen cells from p.v. treated LEW hosts 10 days after transplantation had no suppressor effect on the one-way MLC reaction of normal LEW responder cells toward donor BN or third-party DA stimulators. On the other hand, when serum from p.v.-treated LEW hosts was added to MLC at a concentration of 3 per cent of total volume, it suppressed the MLC reaction toward donor BN cells by 71.6 per cent, but not toward third-party DA stimulators (-8.5 per cent suppression, NS). Histological examination of p.v.-treated LEW hosts at 10 days after transplantation revealed that the liver had normal lobular architecture without expansion of portal tracts and infiltration of inflammatory cells. On the other hand, the transplanted kidney demonstrated a moderate mononuclear cell infiltration around the artery without an interstitial hemorrhage. Moreover, adoptive transfer of the serum from p.v.-treated LEW rats into the virgin secondary LEW hosts significantly prolonged the graft survival of BN kidneys from 7.8 days to 18.9 +/- 5.5 days (P less than 0.01), but not third-party DA graft survivals (MST = 7.5 +/- 0.6 days), indicating that an antigen-specific tolerogenic factor was released into the circulation through the process of allogeneic cells in the liver.

Animals↗
PubMed1990

The effects of perioperative portal venous inoculation with donor lymphocytes on renal allograft survival in the rat. II. Phenotypic and functional analyses of graft-infiltrating cells.

Phenotype, donor-specific cytolytic activity, and helper activity to release cytokines of cells infiltrating within renal allografts of hosts rendered unresponsive by perioperative administration of donor lymphocytes via the portal vein (p.v.) were investigated in order to analyze the mechanism of prolongation of allograft survival. Graft-infiltrating cells (GIC) were obtained from Lewis (LEW, RT-1l) hosts inoculated perioperatively with 1 x 10(8) donor Brown-Norway (BN, RT-1n) lymphocytes p.v., a group that displays prolonged renal allograft survival (MST: 22.2 +/- 5.3 days, n = 10) compared with an uninoculated control group (MST: 7.8 +/- 0.6 days, n = 10, P less than 0.01). The percentages of cytotoxic/suppressor T cells (OX-8+) and Ia-positive cells (OX-6+) in GIC (23.1 +/- 4.4% and 9.0 +/- 2.0%, respectively) and in spleen cells (7.5 +/- 2.6% and 8.5 +/- 1.1%, respectively) from p.v.-inoculated LEW hosts on day 6 postgrafting were significantly lower than those of uninoculated control recipients (GIC: OX-8; 39.4 +/- 8.2%, OX-6; 23.0 +/- 1.9%. SP cell: OX-8; 21.6 +/- 9.9%, OX-6; 12.7 +/- 0.4%, P less than 0.05). Cytolytic activity of GIC from tolerant hosts on day 6 postgrafting toward donor blastoid lymphocytes was significantly decreased (19.0 +/- 1.2% at E/T = 50), compared with that from control allografts during ongoing rejection (51.5 +/- 5.3%, P less than 0.01). The amounts of in vitro cytokine production of GIC from tolerant hosts after mitogen stimulation were remarkably decreased (IL-2: 8.7 +/- 1.4 U/ml, IL-3: 15.4 +/- 0.6 U/ml, and BSF-2: 24.6 +/- 3.5 U/ml) than those of uninoculated control hosts during ongoing rejection (IL-2: 19.6 +/- 2.9 U/ml, IL-3: 22.2 +/- 2.7 U/ml, and BSF-2: 67.5 +/- 13.2 U/ml, P less than 0.05). These results demonstrated that activation of both Tc cells and Th cells was inhibited in the spleen and in situ in renal allografts following administration of donor lymphocytes through the portal vein.

Animals↗
PubMed1990

Septicemia in immunocompromised children and their intestinal flora.

Quantitative fecal bacteriology was performed in eight immunocompromised children with septicemia. The most marked change observed was suppression of the anaerobic bacteria. In seven patients, the predominant organisms were aerobic gram-negative bacilli (GNB), and in six of these were the same as the causative organism of the septicemia. Thus, overgrowth of GNB in the gastrointestinal tract may result in invasion of the blood stream and septicemia in immunocompromised patients. To prevent this complication it is necessary to allow the normal intestinal flora to be maintained in these patients as long as possible. Antibiotics should therefore be prescribed with caution. For the same reason, use of immunosuppressive drugs should be kept to a minimum. Bacteriological examination of the stool and pharynx is useful in the management of immunocompromised patients.

Bacteria↗
PubMed1990

Hormonal induction of beta-casein gene expression: requirement of ongoing protein synthesis for transcription.

Hormonal induction of beta-casein gene expression was studied using a two-step culture of mouse mammary explants and RNA blotting analysis. The explants prepared from pregnant mice were cultured first for 4 days under nonlactogenic conditions to reduce the initial level of beta-casein transcripts and then induced to express beta-casein gene in the presence of insulin, hydrocortisone, and PRL for up to 3 days. Among the six different combination of hormones tested in the first incubation period, the combinations of insulin and epidermal growth factor was found to reduce the residual level of beta-casein transcripts in cultured explants to a nearly undetectable level and allow the highest induction in the second incubation period. The increase in beta-casein transcripts was detected as early as 30 min of induction with insulin, hydrocortisone, and PRL, and its level increased more than 100-fold over the initial level at 24 h. The increase in beta-casein transcripts was blocked by concomitant addition of the protein synthesis inhibitors cycloheximide or puromycin with the three hormones. Cycloheximide inhibited the increase in beta-casein gene transcription that was elicited by insulin, hydrocortisone, and PRL, but did not alter the stability of beta-casein transcripts. These results suggested that protein synthesis was required for hormonal activation of beta-casein gene transcription.

Animals↗
PubMed1990

Involvement of epidermal growth factor deficiency in pathogenesis of oligozoospermia in streptozotocin-induced diabetic mice.

Based on previous findings that epidermal growth factor (EGF), which plays an important role in maintenance of spermatogenesis, is deficient in diabetic mice, the significance of EGF deficiency in the pathogenesis of oligozoospermia in streptozotocin-induced diabetic mice was studied. EGF levels in the submandibular glands and plasma of diabetic mice were 0.61 +/- 0.07 micrograms/mg tissue and 0.25 +/- 0.02 ng/ml (mean +/- SE), respectively, whereas those of normal mice were 1.63 +/- 0.08 micrograms/mg tissue and 0.54 +/- 0.04 ng/ml, respectively. The epididymal sperm counts of diabetic mice, 4.7 +/- 0.14 x 10(5)/mg tissue, were significantly lower (P less than 0.01) than those of normal mice, 6.0 +/- 0.10 x 10(5)/mg tissue. Administration of EGF (5 micrograms/mouse/day) to diabetic mice significantly (P less than 0.01) increased their sperm counts to 5.5 +/- 0.16 x 10(5)/mg tissue without affecting plasma levels of testosterone and glucose. Furthermore, insulin treatment (1 U/mouse/day) of diabetic mice restored the submandibular gland, plasma EGF concentrations, and sperm counts to normal levels. The restorative effects of insulin on sperm production appeared to be mediated, at least in part, by EGF, because its effect was significantly (P less than 0.01) reduced by the concomitant administration of EGF antiserum. In addition, the plasma testosterone levels of diabetic mice, 67 +/- 14.3 ng/ml, were lower that those of normal mice, 122 +/- 19.1 ng/ml. Administration of testosterone (1 mg/mouse/day) normalized the submandibular gland and plasma EGF levels and significantly increased sperm counts in the epididymis. These results suggest that EGF deficiency is a possible cause for the pathogenesis of oligozoospermia in diabetic mice.

Animals↗
PubMed1990

Expression of the epidermal growth factor gene in mouse lachrymal gland: comparison with that in the submandibular gland and kidney.

Expression of the epidermal growth factor (EGF) gene in mouse lachrymal gland was studied. The lachrymal gland of adult male and female mice contained immunoreactive EGF at a concentration of 0.013 +/- 0.002 (S.E.M.) and 0.014 +/- 0.003 ng/mg wet tissue respectively. Northern blot analysis of RNA from the lachrymal gland revealed the presence of 4.1-4.3 kb preproEGF mRNA, which was smaller in size than the 4.7-4.8 kb preproEGF mRNA in the submandibular gland and kidney. There was no sex difference in the mRNA level in the lachrymal gland, whereas the mRNA levels in the submandibular gland and kidney of adult male mice were 42-fold higher and twofold lower respectively than those of female animals. Administration of testosterone propionate or L-thyroxine to female mice increased submandibular gland levels of preproEGF mRNA by 35-fold or 12-fold respectively, but caused no change in lachrymal gland levels of preproEGF mRNA. The level of mRNA in the kidney was decreased by administration of androgen to one-third of that in control animals. The mRNA in the lachrymal gland was detected as early as 2 weeks of age and thereafter it remained at a constant level throughout adulthood, while that in the submandibular gland increased greatly during the pubertal stage. These results indicate differential hormonal and developmental regulation of EGF gene expression in the lachrymal gland, submandibular gland and kidney.

Animals↗
PubMed1990

[Opioid receptors].

Explore the source record for details and available documents.

Adenylyl Cyclase Inhibitors↗
PubMed1990

[Feasibility and radicality of PEP-chemoradiation therapy in oral squamous cell carcinoma].

From 1981 to 1987, 26 patients with oral malignancies, previously untreated squamous cell carcinomas, were treated by chemoradiation therapy, which consisted of Linac irradiation (2 Gy/d) under continuous intraarterial administration of 1.6 mg/d peplomycin (PEP). Twenty of these 26 patients did not undergo resection of the primary sites during initial hospitalization. Radicality of the PEP chemoradiation therapy was assessed after a long-term follow-up. Patients of Stage I to IV numbered 4, 7, 1 and 8, respectively. Total dosage was 60 Gy of Linac irradiation under 80-110 mg infusion of PEP. Overall CR rate and actuarial 5-year-survival rate were 75% and 63%, respectively, while these rates were 92% and 83%, respectively, for the Stage I to III cases, but 50% and 29%, respectively, for the Stage IV patients. Actuarial 5-year-survival rate of the CR Stage I to III cases was 91%, significantly higher than that of Stage IV cases (66%). We conclude the following: (1) This treatment is not indicative for patients with only a limited evaluation of PR available in the early stage of the therapeutic course. (2) Limited or uncertain response might occur in Stage IV cases. (3) The prognosis for the great majority of Stage I to III patients, however, is excellent.

Adult↗
PubMed1990

[Establishment and characterization of a cell line, HS-Os-1 derived from an osteoblastic type of human osteosarcoma].

A new human cell line, HS-Os-1, derived from a case of osteoblastic osteosarcoma arising in the humerus of an 11-year-old girl was established. Light microscopically, HS-Os-1 cells growing in a monolayer (in vitro) were pleomorphic, intermingled with a few multinucleated giant ones, and positive with alkaline phosphatase reaction. In the transplanted tumors in athymic nude mice (in vivo), atypical spindle or polygonal cells densely proliferated with prominent osteoid formation and even calcification. HS-Os-1 cells, both in vitro and in vivo, were mostly positive for vimentin and a few for S-100 protein. Ultrastructurally, HS-Os-1 cells in vitro and in vivo also revealed essentially the same features as the eccentrically located, euchromatin-rich nuclei with prominent nucleoli, a lot of well-developed, irregularly-dilated rough endoplasmic reticula, polysomes and microfilaments in the cytoplasm. Namely, HS-Os-1 cells fully expressed and possessed morphological characteristics as osteoblastic nature during the cultivation and heterotransplantation. This cell line, therefore, proved to be extremely useful to search for human osteosarcomas.

Animals↗
PubMed1990

[Establishment and characterization of a human cell line, HS-MM, derived from a case of clear cell sarcoma].

The characteristics of a new human clear cell sarcoma (CCSa) cell line, HS-MM, established from the pleural effusion in a 39-year-old man with lung metastasis, have been morphologically studied in vitro and in vivo. HS-MM cells growing on a cover-slip were round or spindle in shape with round nuclei containing extremely prominent nucleoli. Heterotransplantation of the cells into nude mice was easily succeeded following tumor development. Light microscopically, HS-MM cells, both in vitro and in vivo, were positive for anti-S-100 protein and anti-melanoma specific antibodies with immunostain, but no melanin pigment was detected in them. Ultrastructurally, the cells had round euchromatin-rich nuclei with large nucleoli revealing conspicuous nucleolonema, and contained a few mitochondria, rough endoplasmic reticulum and lysosomal dense bodies, besides a large amount of glycogen, but no melanosome in their cytoplasm. HS-MM cells retained and fully expressed morphologically unique characteristics as a CCSa, compatible with amelanotic type of malignant melanoma also. This cell line, HS-MM, therefore, proves to be extremely useful for clinicopathological studies on a CCSa.

Adult↗
PubMed1990

[The effect of combination therapy of cyclosporine with steroid on the production of gamma-interferon and interleukin-1 in kidney transplant recipients].

The present study examined the effects of CsA administered with steroid in vivo on the capacity of kidney transplant recipient mononuclear cells to generate cytokines and their gene expression at the level of messenger RNA (mRNA). Peripheral blood mononuclear cells (PBMC) from CsA-Prednisolone (Pred) treated recipients displayed 66.9% inhibition (54.3 + 12.4 IU/ml, n = 42, p less than 0.01) of gamma-IFN production compared with normal individuals (134.6 + 18.6 IU/ml, n = 23). Azathioprine (Az)-Pred treated recipients displayed significantly less inhibition of gamma-IFN generation (96.0 + 16.1 IU/ml, n = 22, p less than 0.05) than CsA treated patients. Macrophages (m phi) from CsA-Pred treated recipients displayed 60.0% inhibition (5.1 + 0.7 U/ml, n = 20, p less than 21). These result were confirmed by the experiments using cDNA probe for gamma-IFN or IL-1 (alpha, beta). High levels of gamma-IFN mRNA in PHA-stimulated PBL or IL-1 (beta) mRNA in LPS-stimulated m phi were present in normal individuals, but not in CsA treated recipients as judged by hybridization to a cloned human gamma-IFN or IL-1 (beta) cDNA probe. These studies demonstrated that combination therapy of CsA with steroid inhibits both gamma-IFN and IL-1 gene expression at the level of mRNA at physiological concentration.

Cyclosporins↗
PubMed1990

[A case of nephrogenic adenoma in the female urethral diverticulum].

A case of nephrogenic adenoma in the female urethral diverticulum is reported. A 39-year-old woman visited our hospital with the chief complaint of perineal pain. Observation of her perineum and transvaginal digital examination revealed urethral diverticulum, and then diverticulectomy was performed. Histological diagnosis was urethral diverticulum associated with nephrogenic adenoma. In Japan, this is the 1st report of nephrogenic adenoma arising in the female urethral diverticulum. We reviewed 305 cases of nephrogenic adenoma of the urinary tract in the English and Japanese literature.

Adenoma↗
PubMed1990

[Prediction of length and width of upper central incisor tooth in multivariate face information].

The possibility of accurately estimating a tooth crown length and width from measured distance of various face points was examined by using Multiple Correlation Analysis. The multiple correlation coefficient between a tooth crown length and the face point was 0.3137 and the residual standard error was 0.820; that between a tooth crown width and the face point was 0.3917 and its standard error was 0.467, obtained by substituted sample data for multiple regression equation.

Analysis of Variance↗