Biomedical subjects
Publications and source records attributed to M Ohashi.
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Negative-ion fast atom bombardment tandem mass spectrometry has been used in the characterization of non-, mono-, di- and trisulfated disaccharides from heparin and heparan sulfate. The positional isomers of the sulfate group of monosulfated disaccharides were distinguished from each other by negative-ion fast atom bombardment tandem mass spectra, which provide an easy way of identifying the positional isomers. This fast atom bombardment collision induced dissociation mass spectrometry/mass spectrometry technique was also applied successfully to the characterization of di- and trisulfated disaccharides.
Characteristics of 205 consecutive patients with hepatocellular carcinoma (HCC) admitted during 1990 to 1993 have been analyzed from the standpoint of hepatitis viral infection in Japan. Among 205 HCC patients, 71% of the patients showed positivity for hepatic C virus (HCV) antibody alone, 13% showed positivity both for HCV and HBV (HCV/HBV) antibody, 11% demonstrated HBsAg alone, and negativity of both HCV and HBV antibody in 4% only. Positivity to both HCV antibody and HBsAg was demonstrated in 1% only. Mean detection age of HCVAb-positive HCC as well as both HCV/HBV antibody-positive HCC was 62 +/- 7 years, in contrast to 52 +/- 13 years in HCC with HBsAg (P < .05). Male-to-female ratio among HCVAb-positive HCC was 3.3:1, in contrast to 5.5:1 among the HCV/HBVAb-positive HCC and 7:1 among HBsAg-positive HCC, but there was no significant difference in the gender distribution between these groups. More than 60% of HCVAb-positive HCC and HCV/HBVAb-positive HCC were classified into the stage of Child B and C, whereas 65% of HBsAg-positive HCC was at the stage of Child A. The severity of liver disease was confirmed by liver histology, indicating that more than 70% of the HCVAb-positive HCC and the HCV/HBVAb-positive HCC showed cirrhosis, in contrast to 50% among the HBsAg-positive HCC. Three-year survival rate of HCV Ab-positive HCC and HBV/HCVAb-positive HCC was 68% and 56%, respectively, in contrast to 47% in HBsAg-positive HCC.(ABSTRACT TRUNCATED AT 250 WORDS)
In Japan, public health regulations state that the water in rinsing pools used before swimming should contain 50-100 mg/l of chlorine. We examined the influence of chlorination at high concentrations in rinsing pools on the skin using cultured human epidermal keratinocytes from normal skin and hypertrophic scars. Chlorination of cell culture for 15 min with 200 mg/l of free residual chlorine proved cytotoxic to both types of keratinocytes as did 100 mg/l of free residual chlorine for 1 or 3 consecutive days. Keratinocytes from hypertrophic scars, when cultivated in 100 mg/l of free residual chlorine, were more vulnerable to chlorine than those from normal skin. Cell characteristics of cultured keratinocytes from hypertrophic scars may be somewhat different from those of normal skin. The phenomena observed in this experimental model of the skin suggest that people exposed to chlorine in rinsing pools at concentrations in excess of 200 mg/l for about 15 min before swimming are at risk of developing cutaneous disorders, especially at sites of injury, e.g. scars.
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Abnormality of p53, a tumor suppressor gene, is considered to be a potential cause of malignancy. We found that ellipticine and 9-hydroxyellipticine (9HE), antitumor alkaloids, caused selective inhibition of p53 protein phosphorylation in Lewis lung carcinoma and SW480 (human colon cancer cell line) in a concentration-dependent manner from 0.1 to 100 microM. 9HE suppressed cdk2 kinase activity concentration-dependently from 1 to 100 microM. By contrast, the inhibition of p53 protein phosphorylation by elliptinium and elliprabin (N2 substituted derivatives of 9HE) was very weak. A good correlation was observed between p53 phosphorylation inhibition and cytotoxic activity of these agents in terms of concentration-response relationships, suggesting that inhibition of p53 protein phosphorylation via kinase inhibition may be involved in the anticancer mechanism of these agents. In addition, this study demonstrated that brief exposure to 9HE caused apoptosis of cancer cells. It is suggested that accumulation of dephosphorylated mutant p53 may induce apoptosis.
We report on case of cervical pregnancy successfully treated by two 5-day courses of etoposide, embryocide with the injection of KCl, the injection of methotrexate into the placenta, and cervical curettage. We evaluated the effects of these treatments by measuring urinary human chorionic gonadotropin (hCG) titers and serial hCG beta-carboxy-terminal peptide (CTP) levels. Moreover, we used ultrasonography and magnetic resonance imaging (MRI) enhanced by gadolinium-diethylenetriamine-pentaacetic acid (Gd-DTPA) to diagnose and to evaluate the blood supply to the trophoblast. The beneficial outcomes suggest that Gd-DTPA-enhanced MRI is useful in detecting the blood supply to the trophoblast, in order to avoid the massive bleeding that results from conservation treatments. This is the first report of the usefulness of Gd-DTPA-enhanced MRI for the successful conservative treatment of cervical pregnancy.
BACKGROUND: Only seven cases of cartilaginous tumors of the skin have been described in the dermatologic literature. OBJECTIVE: We studied the nature of cutaneous cartilaginous tumors and their clinical spectrum. METHODS: We describe a 56-year-old woman with a superficial cartilaginous tumor of the sole of the foot. The tumor appeared to be a cutaneous mass and was resected. RESULTS: Histologically, the tumor extended from the dermis to the subcutaneous tissue. Despite the presence of foci of nuclear changes that suggested a malignancy, there has been no recurrence in the 3 years since its removal. Our review of previous reports indicated that this case may have been a soft tissue chondroma. And it confirmed that cutaneous cartilaginous tumors comprise a superficial soft tissue chondroma and a true cutaneous chondroma primarily located in the dermis. CONCLUSION: Our case appeared to be a cutaneous cartilaginous tumor. A complete local removal is the treatment of choice.
An infant suffered from psoriasiform dermatitis complicated by severe constitutional symptoms. During his 12 months of hospitalization, the symptoms exacerbated periodically despite numerous therapeutic trials. Histologic findings revealed lichenoid psoriasiform dermatitis with striking eosinophilic necrosis of epidermal cells and satellite cell necrosis. Immunohistochemically, CD1+ Langerhans cells had almost disappeared, and CD8+ cytotoxic-suppressor T cells were predominant over CD4+ helper-inducer T cells in the epidermis. These findings in the skin biopsy specimens suggested some similarity to graft-versus-host disease but no known cause of that disorder was proved. Finally, methotrexate was effective. The patient became afebrile, and his skin lesions improved, leaving almost no scarring. This patient seems to have had specific clinical features that do not correspond with any of the known dermatitis. Clinical, histologic, and laboratory findings did not uncover any etiologic factors.
Helicobacter pylori NCTC 11637, which is nonviable at pH 3.0, became viable after addition of 10 mM urea owing to ammonia production by urease. In a buffer supplemented with urea, ecabet sodium decreased both the production of ammonia and the number of viable cells of H. pylori NCTC 11637 and changed the bacteria from the bacilliform to the horseshoe or doughnut shape in a concentration-dependent manner. In particular, ecabet sodium (2 and 4 mg/ml) decreased the number of viable cells below the control level. Benzohydroxamic acid, a urease inhibitor, also caused a decrease in ammonia production accompanied by a decrease in the number of viable cells and changed the morphological form at pH 3.0, but the number of viable cells was not lowered below the control level. In buffers at various pHs without urea, ecabet sodium showed a concentration-dependent bactericidal effect on H. pylori at pHs 4.0 and 5.0 but not at pHs 6.0 and 7.0 while benzohydroxamic acid caused only a slight decrease in the number of viable cells at pH 4.0. These results suggest that ecabet sodium has strong bactericidal activity in addition to its urease-inhibiting activity under acidic conditions.
We experienced a case of renal hamartoma of mesothelial origin. A 21-year-old was referred to our hospital with a complaint of growing abdominal mass. The diagnosis of right renal tumor was confirmed based on the radiographic examinations. The renal tumor was removed by partial nephrectomy. Histological examination revealed the tumor composed of fibroblasts, smooth muscle and a few tubule-like epithelial tissue. Thus, this case was classified as renal hamartoma of mesothelial origin.
We have experienced 7 cases of laparoscopic adrenalectomy for adrenal tumors during the past two years since our department opened in July, 1992. In four cases, the tumors were clinically diagnosed preoperatively as primary aldosteronism and in the other three cases as endocrine-inactive tumors. Four tumors were found on the left adrenal and three on the right. Five tumors were successfully resected with laparoscopic surgery, but in the other two cases it was immediately followed by open surgery because of an uncontrollable hemorrhage. Laparoscopically unresected tumors existed, one on the right and the other on the left adrenal. The average operation time for laparoscopic adrenalectomy was twice as much as that of open adrenalectomy previously performed. However, the operation time has been recently shortened to be less than 200 minutes. Hemorrhage during the operation was rather less in laparoscopic surgeries if they were successfully done. Postoperative recovery was found to be much faster and the hospital stay was shortened by more than 10 days in patients operated with a laparoscope. These findings indicate that laparoscopic adrenalectomy is a minimally invasive operation that can increase the QOL's of the patient. Although we consider that this operation may propagate as a method for adrenalectomy in future, it must be performed with a careful backup system in the case of an emergency.
A 62-year-old male patient presented with a complaint of the lower abdominal distention. Ultrasonography demonstrated bilateral hydronephroses and a huge heterogeneous mass in the pelvic cavity. Excretory urogram showed left-non visualized kidney and right-hydronephrosis. CT showed a heterogenous mass, situating 25 cm in diameter, adjacent to the left side of the bladder. Tumor resection was carried out on May 17th of 1994. Histopathological diagnosis of the surgical specimen was abdominal desmoid with HE stain.
Ritodrine hydrochloride is widely used in clinical obstetrics for the prevention of premature labor, but the knowledge of its effect on fetal circulation is limited. The purpose of this study was to elucidate changes in vascular resistance in the fetal placental circulation by using the dually perfused human placenta in vitro. The viability of the perfused placenta was maintained during the experiments because the production rate of hCG was constant. The transfer of ritodrine hydrochloride was observed and its concentration on the fetal side was about one third of maternal side at 120 min subsequent to the injection. The fetal perfusion pressure during the control period was 38.6 +/- 7.0 mmHg (mean +/- S.D., n=3). After the addition of ritodrine hydrochloride to the maternal circulation, the fetal perfusion pressure was decreased dose-dependently. The pressure was 95.4 +/- 1.8% at 80 ng/ml of ritodrine hydrochloride which was within the clinical concentration limits. It is concluded that ritodrine hydrochloride acts as a vasodilator on the fetal vasculature in the human placenta.
The role of protein phosphorylation in the formation of secretory vesicles from the trans-Golgi network (TGN) and in the regulation of this process by TGN-associated trimeric G-proteins was investigated, using a previously established and a novel cell-free system derived from the neuroendocrine cell line PC12. In the absence of exogenous activators of trimeric G-proteins, okadaic acid, an inhibitor of protein serine/threonine phosphatase types 1, 2A, and PPX, had no significant effect on secretory vesicle formation as reconstituted in a postnuclear supernatant. However, okadaic acid antagonized the inhibition of secretory vesicle formation which occurred upon activation of trimeric G-proteins by either aluminum fluoride or guanosine 5'-3-O-(thio)-triphosphate (GTP gamma S). Microcystin-LR, a protein phosphatase inhibitor structurally distinct from okadaic acid, also antagonized the trimeric G-protein-mediated inhibition of secretory vesicle formation but, in contrast to okadaic acid, alone was sufficient to stimulate this process. The antagonistic effect of the phosphatase inhibitors was abolished by a broad spectrum protein kinase inhibitor, staurosporine, which alone, however, did not affect vesicle formation. The effect of okadaic acid was promoted by activators of protein kinase C (phorbol myristate acetate) and protein kinase A (cyclic AMP). To investigate the subcellular localization of the phosphoprotein that is involved in the antagonistic effect of protein phosphatase inhibitors, a novel cell-free system was established which reconstitutes the formation of secretory vesicles from TGN membranes supplemented with cytosol. Using this cell-free system, the relevant phosphoprotein was found to reside in the cytosol. In conclusion, our results suggest that serine/threonine protein phosphorylation is not required for secretory vesicle formation from the TGN but modulates, via a cytosolic phosphoprotein, the regulation of this process by TGN-associated trimeric G-proteins.
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The proliferative effects of humoral factors released from N18-RE105 neuroblastoma (NRE) cells on cultured astrocytes were assessed in separate co-culture and conditioned medium studies. In both experimental conditions, the humoral factors derived from neuroblastoma cells had growth-promoting effects on C6 glioma cells of astroglial lineage, but not on primary cultured astrocytes from new-born rat cerebral cortex. It is assumed that neuron-derived humoral factors include astroglial growth factors and that differences in responsiveness between two kinds of cells are probably related to the stages of astroglial maturation processes.
The concentrations of pancreastatin-like immunoreactivity (PST-LI) of the cerebrospinal fluid (CSF) were measured in the patients with Alzheimer type dementia (ATD) and in age-matched normal subjects. The mean PST-LI concentration in the CSF of ATD patients was significantly lower than that of normal subjects. Gel chromatographic analysis revealed that the main PST-LI peak of ATD's CSF eluted at molecular weight (MW) 13.5 kDa. However, the age-related change of the molecular forms of PST-LI in CSF was observed in normal subjects as following; PST-LI in neonatal CSF showed one peak at MW 13.5 kDa, that of 16-64-year-old showed two peaks at MW 13.5 and 5.4 kDa, however, only one main peak was shown at MW 5.4 kDa in the CSFs of 72-85-year-old. These findings suggest that the production of PST-LI was decreased and the proteolytic cleavage, which should process big PST to PST (1-52) in normal subjects, was altered to that of neonatal type in the CNS of the patients with ATD.