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Biomedical subjects

K Ohashi

Publications and source records attributed to K Ohashi.

At least 415 records · Page 23Linked to original sources
PubMed1992

The fetus as an allograft: immunobiologic role of human trophoblasts for fetal survival.

OBJECTIVE: The hypothesis of this study is that trophoblasts contribute to the survival of the mammalian fetal allograft. STUDY DESIGN: Immunologic and molecular biologic studies were performed with human trophoblasts or trophoblastic tumor cells to investigate the expression of class I human leukocyte antigens, the susceptibility to natural killer and lymphokine-activated cells, the ontogeny of Fc gamma-receptors, and the production of immunosuppressive factors. RESULTS: Heterogeneous expression of class I human leukocyte antigens on trophoblasts was regulated at transcriptional level. Trophoblasts showed low susceptibility to natural killer and lymphokine-activated cells. Trophoblasts expressed natural killer cell-type Fc gamma-receptor III, which mediates phagocytosis. The trophoblast-derived immunosuppressive factor was very similar to transforming growth factor-beta. CONCLUSION: The trophoblasts, which ultimately form the fetoplacental interface, constitute a major immune barrier for the survival of the allogenic conceptus.

Female↗
PubMed1992

Cervical discs are most susceptible to beta 2-microglobulin amyloid deposition in the vertebral column.

Intervertebral discs of 41 chronic renal failure autopsy cases were examined histologically and immunohistochemically to assess the distribution of beta 2-microglobulin-associated (beta 2m) amyloid in the vertebral column. The results demonstrated beta 2m amyloid to appear first in the cervical discs, then in the lumbar and upper thoracic discs, and finally in the middle and lower thoracic discs as the dialysis period is prolonged. The shortest dialysis period for which beta 2m amyloid was detected was one year and seven months. Deposition of beta 2m amyloid was most remarkable in the C4-5, 5-6, and 6-7 levels, which are known to sustain severe mechanical stress in daily life. Thus it is suggested that local mechanical stress accelerates beta 2m amyloidosis. A marked macrophage reaction was observed around the amyloid in cases of severe amyloidosis, the macrophages themselves being immunohistochemically positive for IL-1 beta and TNF-alpha. Amyloid deposition and reactive inflammation mediated by cytokines appear to be closely related to the pathogenesis of destructive spondyloarthropathy.

Adult↗
PubMed1992

Production of multiple growth factors by a newly established human thyroid carcinoma cell line.

A multiple growth factor-producing tumor cell line (NIM-1) was newly established from a patient with thyroid cancer and remarkable neutrophilia. NIM-1 cells also caused severe neutrophilia in nude mice bearing tumors. NIM-1-conditioned medium (NIM-1CM) contained activities that supported not only granulocyte, macrophage and eosinophil colony formation of human bone marrow cells but also the growth of colony-stimulating factor (CSF)-dependent cell lines, NFS60-KX and TF-1. Northern blot hybridization analysis revealed the constitutive expression of granulocyte-CSF (G-CSF), granulocyte/macrophage-CSF (GM-CSF) and interleukin(IL)-6 mRNAs in NIM-1 cells. Enzyme-linked immunosorbent assays (ELISA) using NIM-1CM also confirmed the production of IL-1 alpha and a small amount of IL-1 beta besides G-CSF, GM-CSF and IL-6 in NIM-1 cells. In addition, unexpected production of IL-11 in NIM-1 cells was detected by northern blot hybridization analysis and by bioassay using an IL-11-dependent cell line. Therefore, NIM-1 cell line is shown to produce multiple cytokines including potentially megakaryopoietic growth factors such as GM-CSF, IL-6 and IL-11.

Adenocarcinoma, Papillary↗
PubMed1992

A probable case of superfecundation.

Discordant twins are of obstetrical concern because of high morbidity and mortality of either the smaller or the larger twin, or both. The discordance becomes apparent usually in the second trimester. We report a case of discordant twins diagnosed in the 10th week of gestation, which was concluded to be a case of superfecundation. The discordancy was persistent up to the 35th week of gestation, when 2 baby boys were born by cesarean section because of preeclampsia. The postnatal courses of the babies were uneventful.

Adult↗
PubMed1992

Tumor necrosis factor-alpha inhibits human chorionic gonadotropin secretion.

The placenta is a major source of tumor necrosis factor-alpha (TNF alpha) and is rich in TNF alpha receptors. TNF alpha inhibited hCG secretion by normal chorionic villi at 6 weeks gestation, but chorionic villi contain the heterogenous cell population. To investigate the direct effects of TNF alpha on trophoblasts, the NUC1 choriocarcinoma cell line was used as an in vitro placental cell model. TNF alpha also inhibited hCG secretion by NUC1 cells at concentrations from 1-100 U/mL. TNF alpha at concentrations of 1, 10, and 100 U/mL significantly decreased hCG secretion for 24 h to 88%, 81%, and 71% of the control level, respectively. The expression of hCG beta mRNA was also decreased to 23% of the control level after 24 h of TNF alpha treatment (100 U/mL). Inhibition occurred after 12 h of TNF alpha treatment (100 U/mL). Two measurements, trypan blue dye exclusion and 3-(4,5-dimethylthiazol-2-yl)2,5-diphenyl tetrazolium bromide reduction, revealed that these inhibitory effects were not due to the cytotoxic activity of TNF alpha on NUC1. In conclusion, TNF alpha reduces hCG secretion in vitro.

Blotting, Northern↗
PubMed1992

Influence of adrenalectomy on chronopharmacological phenomenon of furosemide in rats.

The role of adrenal corticoids in the time-dependent changes in the effects of furosemide was examined. Furosemide (30 mg/kg) was given orally to adrenalectomized or sham-operated rats at 12 a.m. or 12 p.m. Urine volume and urinary excretion of sodium and furosemide for 8 hr were significantly greater at 12 a.m. than at 12 p.m. in the sham-operated rats. However, such time-dependent changes in these parameters disappeared in the adrenalectomized animals. These findings indicate that adrenal corticoids are directly or indirectly involved in this event.

Adrenal Cortex Hormones↗
PubMed1992

Chronopharmacology of probucol in mice.

Mice were maintained under conditions of light from 7 a.m. to 7 p.m. and dark from 7 p.m. to 7 a.m. Probucol was given orally to these animals once daily at 10 a.m. or 10 p.m. for 7 days. Blood samples for serum cholesterol were obtained at 24 hours after the final dosage. Blood samples for plasma probucol were obtained just before and at 3, 6, 12, 24, 48, 72, 96 and 120 hours after the final dosage. The cholesterol lowering effect of the agent at 10 p.m. was greater than that at 10 a.m. Plasma probucol concentrations of the two trials did not differ at any observation point. These data suggest that the effect of probucol varies with its time of administration. This might not be caused by a time-dependent change in plasma probucol concentration.

Administration, Oral↗
PubMed1992

Influence of DOCA treatment on administration-time-dependent changes in the effects of furosemide in saline-loaded rats.

We have previously found that the administration-time-dependent change in the effects of furosemide, a loop diuretic agent, is observed in normal rats. The present study was undertaken to examine whether an alteration in this phenomenon occurs in rats with DOCA-saline hypertension. Unilateral nephrectomized rats were divided into three groups. The first group (DOCA-saline) received a 50 mg DOCA tablet intraperitoneally and drank 1% NaCl solution. The other two groups were given sham operations. A 1% NaCl solution was given as drinking water to the second group (control-saline), while tap water was given to the third group (control-water). Furosemide (30 mg/kg) was given orally to each group at 12 a.m. or 12 p.m. Urine was collected for 8 hours after the agent, and urinary excretion of sodium and furosemide were determined. Urine volume and urinary excretion of sodium and furosemide following the agent were significantly greater at 12 a.m. than at 12 p.m. in the control-water and control-saline groups. However, the administration-time-dependent changes in these parameters disappeared in the DOCA-saline rats. These results suggest that the mode of the administration-time-dependent changes in the effects of furosemide is altered in the DOCA-saline hypertensive rats.

Animals↗
PubMed1992

Chronopharmacology of furosemide in rats with amikacin-induced acute renal damage.

To examine the influence of amikacin-induced acute renal damage on the urinary excretion of furosemide and the time-dependent variation in the urinary amount of the agent, amikacin (1.2 g/kg) was given intraperitoneally to Wistar rats. Study I: Three percent b.w. of 1% NaCl solution was given orally before and after amikacin treatment, and an 8-hour urine for N-acetyl-beta-D-glucosaminidase (NAG) was collected. Study II: Furosemide (30 mg/kg) in 3% b.w. of 1% NaCl solution was given orally at 12 a.m. or 12 p.m. before and after amikacin treatment, and an 8-hour urine for sodium and furosemide was collected. Following amikacin treatment, urinary excretion of NAG increased, while urine volume and urinary excretion of sodium and furosemide decreased. Urinary excretion of furosemide and its diuretic effects were significantly greater at 12 a.m. than at 12 p.m. before and after treatment. However the time-dependent differences in these parameters were diminished by amikacin treatment. These results suggest that the urinary excretion of furosemide is reduced and the extents of the time-dependent variation in the urinary furosemide and its diuretic effects are altered in rats with amikacin-induced renal damage.

Acetylglucosamine↗
PubMed1992

Daily variation in the effects of furosemide in rats.

Daily variation in the effects of furosemide, a loop diuretic agent, was examined in Wistar rats maintained under conditions of light from 7 a.m. to 7 p.m. and dark from 7 p.m. to 7 a.m. Furosemide (30 mg/kg) was given orally at 12 p.m., 4 a.m., 8 a.m., 12 a.m., 4 p.m. or 8 p.m. Urine was collected for 8 hr after furosemide administration, and urinary excretions of sodium and furosemide were determined. There were significant daily variations in the urine volume and urinary excretions of sodium and furosemide with a peak at 8 a.m. and a trough at 12 p.m. Significant correlations were observed between the urinary amount of furosemide and its diuretic effects (urine volume and urinary sodium excretion). These results suggest that the diuretic effects of furosemide show daily variations which are, at least in part, caused by the daily variation in the urinary excretion of furosemide.

Animals↗
PubMed1992

Diurnal effect on caffeine acetylation phenotyping: a preliminary report.

The present study examined whether caffeine acetylation phenotype could be altered by its time of administration. Caffeine was given orally to nine healthy subjects at 10 a.m. and 10 p.m. and acetylation phenotype was determined by measuring the major metabolites of caffeine in urine. The results showed that acetylation phenotypes determined in the day trial were not different from those determined during the night trial.

Acetylation↗
PubMed1992

The effect of hypoxia on brain edema--the promoting effect of superimposed hypercapnia or hypertension.

The effects of hypoxia and superimposed hypercapnia or hypertension during hypoxia on brain tissue water content, pH, and electric activity were studied in Sprague-Dawley and stroke-prone spontaneously hypertensive rats. Auditory brainstem responses and sensory evoked potentials were recorded during the experiment as the indices for cerebral oxygen metabolism. The brains were removed immediately, 1 day, and 2 days after hypoxic insult for gravimetric study. The brain water content increased in all groups on the 1st and 2nd days after hypoxia. The percentage change from the control water content increased only on the 1st day in hypoxic rats. In contrast, it increased on both the 1st and 2nd days after hypoxia in hypercapnic or hypertensive rats. The evoked potentials of hypoxic and hypercapnic-hypoxic rats showed that peak latencies were prolonged significantly during hypoxia and recovered 1 and 2 days after hypoxia. The brain tissue pH decreased during hypoxia and recovered after hypoxia. This study suggests that brain edema develops within 2 days of hypoxic insult and that superimposed hypercapnia or hypertension promotes the brain edema.

Animals↗
PubMed1992

Preparation of oligozoospermic and/or asthenozoospermic semen for intrauterine insemination using the SpermPrep semen filtration column.

OBJECTIVE: To improve the quality of oligozoospermic and/or asthenozoospermic semen by the SpermPrep (Fertility Technologies Inc., Natick, MA) semen filtration column. DESIGN: The SpermPrep column was applied for semen manipulation in oligozoospermia and/or asthenozoospermia (sperm count less than 20 x 10(6)/mL, sperm motility less than 40%). After concentration of motile sperm using a 40% Percoll density gradient centrifugation, the sperm suspension was filtered through the SpermPrep column. The percentage yield of motile sperm by the SpermPrep method was compared with those by a two-layer Percoll density gradient (Pharmacia, Uppsala, Sweden) centrifugation and a swim-up method. Infertile couples with poor quality semen were treated with intrauterine insemination (IUI) with motile sperm by the three preparations through three cycles. SETTING: Department of Obstetrics and Gynecology, Osaka University Hospital. PATIENTS: Twenty-one couples with long-standing infertility because of poor quality semen. MAIN OUTCOME MEASURE: Recovery of motile sperm, sperm motility, and outcome of IUI were evaluated among three semen preparations. RESULTS: Motility was improved by the SpermPrep method in 32 of 33 cases of oligozoospermia and/or asthenozoospermia. Percentage yield of motile sperm by the SpermPrep method was significantly greater than those by the two-layer Percoll density gradient and swim-up methods (42.7 +/- 4.6 versus 22.1 +/- 3.1 and 13.8 +/- 3.5), but there is no significant difference in the sperm motility among three semen preparations. After one treatment cycle for each preparation, 2 of 21 women conceived after IUI with motile sperm separated in the SpermPrep method. CONCLUSIONS: The SpermPrep method is an improved semen manipulation method for oligozoospermia and/or asthenozoospermia.

Cell Separation↗
PubMed1992

[Pharmacokinetic studies of menogaril (TUT-7) with rats].

Menogaril (TUT-7) is a novel antitumor antibiotic belonging to anthracyclines. The pharmacokinetic parameters derived from plasma concentration-time profiles after repeated (for 14 days) or single oral administration of TUT-7 to rats were found to be not significantly different by either administration schedule. The rats with artificial liver dysfunction were obtained by subcutaneous application of carbon tetrachloride (CCl4, 1 ml/kg) for 3 days. After oral administration of TUT-7 to the rats with CCl4-induced liver toxicity (3 daily administrations of 1mg/kg, S.C.), the maximum plasma concentrations (Cmax) and AUC of both the unchanged drug and its metabolite N-Demethyl menogaril, were increased. Also over all elimination was slower in animals with liver dysfunction.

Administration, Oral↗
PubMed1992

Evaluation of acrosomal status using MH61-beads test and its clinical application.

OBJECTIVE: To evaluate the acrosomal status of viable sperm by MH61-beads test and its clinical application. DESIGN: Acrosomal status was evaluated using immunobeads coated with MH61 monoclonal antibody, which is specific for acrosome-reacted sperm. When viable sperm was coincubated with MH61-beads for an appropriate length of time, the formation of a sperm-bead complex was observed with a phase-contrast microscope, and the number of sperm binding to MH61-beads increased with the progression of the acrosome reaction. Using this agglutination, we developed the MH61-beads test to assess sperm function. SETTING: Department of Obstetrics and Gynecology, Osaka University Hospital. PARTICIPANTS: Forty-three volunteers and 20 males in our in vitro fertilization (IVF) and embryo transfer program. MAIN OUTCOME MEASUREMENT: The results of MH61-beads test were compared with the percentage of acrosome-reacted sperm detected by Pisium satinum agglutinin staining on 30 volunteers, with the results of sperm penetration assay (SPA) in 43 volunteers, and with the outcome of IVF in 20 patients. RESULTS: The results of MH61-beads test showed good reproducibility and correlated with the results of SPA using zona-free hamster eggs and IVF. CONCLUSIONS: The MH61-beads test, the results of which reflect the acrosomal status of sperm, may provide useful information concerning the fertilizing ability of sperm.

Acrosome↗
PubMed1992

A multi-institute case-control study on the risk factors of developing pancreatic cancer.

A multi-institute, hospital-based, case-control study on pancreatic cancer was carried out to examine its association with preceding diseases, cigarette smoking, alcohol drinking and dietary factors. Analyses were based on 124 newly diagnosed exocrine pancreatic cancer cases and sex-, age- and institute-matched hospital controls in seven hospitals in Japan. Cigarette smoking showed a positive association with the risk of developing pancreatic cancer. Especially among smokers, a risk enhancing effect of involuntary/passive smoking prior to twenty years of age was observed (P < 0.05). No consistent associations were found with coffee, black tea or alcohol consumption. Among dietary factors, favoring food of a salty taste and drinking green tea five cups per day or more were positively associated with the risk. Drinking milk and eating fish everyday were inversely associated with the risk.

Adult↗
PubMed1992

[Results of non-decompression surgery for esophago-gastric varices--postoperative disappearance, recurrence, rebleeding rate of varices, and cumulative survival rate].

A total of 508 patients had an non-decompression surgery for esophago-gastric varices in our department, from September 1979 to December 1991. These patients consisted of 387 cases of transthoracic esophageal transection with para-esophagogastric devascularization, 40 cases of transabdominal esophageal transection, and 81 cases of Hassab procedure. The original diseases were cirrhosis in 432 patients, IPH in 35, extrahepatic-portal occlusion in 24, primary biliary cirrhosis in 6, Budd-Chiari syndrome in 4, and others in 7. Operative mortality rate was 5.3%. By thoracic approach, esophageal varices completely disappeared. Postoperative cumulative variceal recurrence and bleeding rates at 10 years were 12% and 7%, although recurrence occurred more often than not in cases with hepatocellular carcinoma (HCC). Cumulative survival rates at 5, 10 years were 69%, 46% in liver cirrhosis without HCC. Present study confirmed that our non-decompression surgery is effective in controlling esophagogastric varices in long term of periods.

Esophageal and Gastric Varices↗