Biomedical subjects

S Goto

Publications and source records attributed to S Goto.

At least 433 records · Page 24Linked to original sources

PubMed1995

Significance of glutathione depletion and oxidative stress in early embryogenesis in glucose-induced rat embryo culture.

Recent studies have demonstrated the protective effects of supplementing free oxygen radical scavenging enzymes against hyperglycemia-induced embryonic malformations. In this study, the glutathione (GSH)-dependent protection system in hyperglycemia-induced embryopathy was investigated. Rat embryos at the early head-fold stage (day 9.5) cultured in 66.7 mmol/l glucose for 48 h showed significant growth retardation and an increase in the frequency of malformations. The concentration of GSH and activity of the rate-limiting GSH-synthesizing enzyme, gamma-glutamylcysteine synthetase (gamma-GCS), significantly decreased in embryos exposed to hyperglycemia compared with controls (7.9 +/- 0.6 vs. 12.5 +/- 0.9 nmol/mg protein, P < 0.01 and 13.3 +/- 1.9 vs. 22.6 +/- 1.1 microU/mg protein, P < 0.01, respectively). Decreased activity of gamma-GCS in embryos exposed to hyperglycemia was associated with decreased expression of gamma-GCS mRNA levels. However, the activities of superoxide dismutase and glutathione peroxidase did not significantly change in these embryos. Extracellular and intracellular free oxygen radical formations estimated by Lucigenin-dependent chemoluminescence and flow cytometric analysis using 2',7'-dichlorofluorescein diacetate increased in isolated embryonic cells taken from embryos cultured under hyperglycemia. Supplementation of 2 mmol/l GSH ester into the hyperglycemic culture nearly restored GSH concentration in these embryos (11.9 +/- 0.5 vs. 12.5 +/- 0.9 nmol/mg protein) and reduced the formation of free oxygen radical species leading to almost complete normalization of growth retardation and embryonic dysmorphogenesis.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1995

Thrombosed growing giant aneurysms of the vertebral artery: growth mechanism and management.

Results in three patients with thrombosed giant aneurysms of the vertebral artery are reported. Each of the aneurysms presented as a mass lesion. On postcontrast computerized tomography and magnetic resonance imaging, each aneurysm demonstrated a patent lumen and intrathrombotic vascular channels. Two patients died and were autopsied, and the other patient was successfully treated. Pathological examination revealed that the aneurysms had staged clots, an open lumen, intrathrombotic channels with endothelial lining, and aneurysmal walls with intimal thickening. The authors suggest that the development of the intrathrombotic capillary channels may be an important factor in the growth of thrombosed giant aneurysm of the vertebral artery. Trapping of the aneurysm followed by aneurysmectomy appears to be the best treatment for this type of aneurysm.

Adult↗

PubMed1995

[Statistical analysis of press-through-pack foreign body in the esophagus and its experimental investigation].

A statistical analysis was performed in patients with press-through-pack (PTP) foreign body in the esophagus encountered in the Department of Otorhinolaryngology, Tohoku University School of Medicine, from 1986 to 1993. Furthermore, the radiolucency of PTP and the possibility of mucosal injury of the esophagus by PTP were examined by experimental methods. We obtained the following results: 1) The incidence of PTP foreign body in the esophagus increased in the period from 1986 to 1994 as compared with that from 1978 to 1985. 2) PTP foreign body was lodged in the following area: cricopharyngeal narrowing > bronchio-aortic narrowing > hiatal narrowing. 3) Fluoroscopy with or without contrast material and flexible endoscopy were useful tools for diagnosis. 4) Direct esophagoscopy revealed mucosal erosion, hematoma, edema and intact mucosa in 14, 3, 3, and 6 patients, respectively. 5) The period of hospitalization was longer in patients with mucosal erosion than in those with intact mucosa. 6) The base of PTP made of aluminium could be detected as a radiopaque material by lateral projections, suggesting that PTP foreign bodies require roentgenograms made parallel to the base of PTP. 7) Histological study indicated that traumatic lesions in the extracted esophagus manually produced by the sharp corner of PTP were present in the mucosal layer and partially in the submucosal layer, suggesting that esophageal perforation by PTP was generated by additional factors such as secondary infection and iatrogenic trauma induced by esophagoscopy.

Adult↗

PubMed1995

Early compressive strength and phase-formation of dental amalgam.

The compressive strength of five different amalgams was measured at one hour, six hours, 24 hours, and seven days, and X-ray diffraction analysis was carried out for each amalgam at the same times in order to investigate the early strength characteristics of the amalgams in relation to the formation of different phases. At 24 hours all tested amalgams reached about 90% or more of their seven-day compressive strength, but the increase in the early compressive strength from one hour to 24 hours varied between different amalgams. Two of the five amalgams tested reached about 90% of their seven-day compressive strength at six hours. A significant correlation was found between the ratio of early compressive strength to seven-day compressive strength, and the X-ray diffraction intensity ratio (ratios of one-, six- and 24 hour intensity to seven-day intensity) for the gamma 1 phase, indicating that the increases in early compressive strength are mainly dependent upon the formation of gamma 1.

Analysis of Variance↗

PubMed1995

Effects of 20 days bed rest on mechanical efficiency during upright cycling and leg muscle mass in young males.

Delta efficiency defined as increase in work over the corresponding increase in energy liberation (delta work/delta energy) may be used to express the efficiency of working muscles under standard conditions where work is performed with similar changes in muscle length, identical pedal revolution frequencies, and contraction-to-relaxation ratios. The Delta efficiency is probably the most valid measure of the efficiency of muscular work, so it may be influenced by the difference in distribution and/or density of muscle fiber types in exercising muscles. It has been reported that after bed rest of 7-14 days, not only maximum oxygen uptake (VO2 max) but also oxygen uptake (VO2) at 3-min submaximal upright exercise decreased. However, the decrease might be apparent, and the mechanical efficiency might be unchanged. On the other hand, muscle mass of bicycling legs was decreased after continuous horizontal bed rest of 10 days and 20 days. Because the decreased muscle mass is probably related to decrease in the density of the slow twitch muscle fibers (ST-fiber), the decrease in submaximal VO2 during bicycle exercises after bed rest may result from a decrease in ST-fiber mass. Therefore, it could be hypothesized that the mechanical efficiency should increase during upright exercise because of the relative increase in amount of more efficient fast twitch muscle fibers (FT-fiber) than ST fibers in exercising muscles. The purpose of the present study was to investigate whether delta efficiency in working muscle is influenced by the decrease in muscle mass after 20 days horizontal bed rest in young males.

Adult↗

PubMed1995

Expression and localization of inducible nitric oxide synthase in anti-Thy-1 glomerulonephritis.

To elucidate a possible involvement of nitric oxide in the development of a mesangial proliferative glomerulonephritis induced by anti-Thy-1 antibody administration, glomerular expression of three isoforms of NO synthase (NOS), inducible NOS (iNOS), brain NOS, and endothelial NOS, was examined at both mRNA and protein levels by ribonuclease protection assay and immunofluorescence microscopy. Light microscopy showed an accumulation of polymorphonuclear leukocytes at 1 hour, lysis of mesangial cells at 1 day, a mesangial proliferative lesion at 4 to 10 days, and minimal residual glomerular lesions by 28 days. Ribonuclease protection assay showed that the glomerular expression of iNOS mRNA peaked at 1 hour and decreased thereafter. No substantial expression of iNOS mRNA was observed in normal glomeruli or in the nephritic glomeruli obtained at different time points (1, 4, 10, or 28 days). By immunofluorescence microscopy with a specific monoclonal antibody, an intense reaction for iNOS was demonstrated in a few cells in the glomeruli at 1 hour. Most of the iNOS-positive cells were identified as polymorphonuclear leukocytes. iNOS-positive cells were found less frequently in the glomeruli on days 1 and 4. Endothelial NOS mRNA was constitutively expressed in normal glomeruli and increased biphasically with two peaks at 1 hour and at 4 days or later; however, the peak expression was much less than that of iNOS mRNA at 1 hour. Expression of brain NOS mRNA was not detectable in either normal or nephritic glomeruli. These results show that iNOS is predominantly expressed in polymorphonuclear leukocytes accumulating at 1 hour in the glomeruli of anti-Thy-1 glomerulonephritis and suggest an involvement of NO in the initiation of the disease.

Animals↗

PubMed1995

[A case report of far advanced gastric cancer with multiple liver metastasis (H3) treated with transarterial intermittent chemotherapy and intradermal administration of low molecular lipopolysaccharide (LPSp) extracted from Pantoea agglomerans].

A case of far advanced gastric cancer with multiple liver metastasis (H3) was treated with transarterial intermittent chemotherapy (5-FU: 250 mg/week, Farmorubicin: 10 mg/4 weeks, MMC: 4 mg/2 weeks) and intradermal administration of low molecular lipopolysaccharide (LPSp) extracted from Pantoea agglomerans. The CT examination and endoscopy showed regression of the tumor and the patient was discharged from the hospital. LPSp was given at the concentration of 0.1 microgram initially, and the dose was gradually increased. Finally, the dose of LPSp was increased up to 70 micrograms. No serious side effect except fever was observed. The serum TNF-alpha levels were elevated and, histologically, CD 8(+) lymphocyte dominantly infiltrated around the tumor. These findings clearly indicated the immunological anticancer effect of LPSp. Intradermal administration of LPSp is a promising new adjuvant therapy to improve QOL without serious side effect.

Aged↗

PubMed1995

[Treatment of sclero-corneomalacia after cataract surgery].

We treated sclero-corneomalacia in an 84-year-old woman, which occurred 7 months after cataract surgery on her left eye. Since medical therapy could not prevent progress of the sclero-corneal lesion and perforation of the eyeball was likely, we performed implantation of preservable sclera and keratoepithelioplasty. The patient has an uneventful postoperative course without recurrence and good visual acuity was preserved. To minimize the post-operative inflammation and early reform of the ocular surface, implantation of preservable sclera and keratoepithelioplasty is an effective procedure.

Aged↗

PubMed1995

[Superselective local infusion therapy with tissue-plasminogen activator for acute massive pulmonary thromboembolism: preliminary clinical experience].

Three cases of acute massive pulmonary thromboembolism were treated with the superselective infusion of tissue-plasminogen activator. Superselective pulmonary angiography immediately after administration of tissue-plasminogen activator demonstrated angiographic improvement in all patients. No complications were encountered during or after the procedure. It is considered that superselective infusion of tissue-plasminogen activator can be an effective therapy for massive pulmonary thromboembolism.

Acute Disease↗

PubMed1995

Isoforms of PML-retinoic acid receptor alpha fused transcripts affect neither clinical features of acute promyelocytic leukemia nor prognosis after treatment with all-trans retinoic acid. The Leukemia Study Group of the Ministry of Health and Welfare (Kohseisho).

All-trans retinoic acid (ATRA) has been used as a potent differentiation drug for acute promyelocytic leukemia (APL). Although the mechanism of its effectiveness upon APL remains unclear, the PML-retinoic acid receptor alpha (RARA) chimeric protein produced by t(15;17) is assumed to underlie the sensitivity of APL cells to ATRA. There are two major isoforms of PML-RARA transcripts; short (S) and long (L), according to the breakpoints in the PML gene. We therefore compared the clinical variables, the response to ATRA and the prognosis between 28 patients with type S and 68 patients with type L. Patients were treated in multi-institutional trials with ATRA, and chemotherapy was combined when peripheral blasts and leukocyte counts increased during the therapy. The clinical features at diagnosis were similar between the two molecular subtypes, and there was no significant difference in remission induction rates; 86% for the type S group and 90% for the type L group. There was no statistical difference in overall survival and CR duration as well as disease-free survival (DFS). In newly diagnosed patients, predicted 2-year DFS was 66% for the type S group and 67% for the type L group. In refractory or relapsed patients, it was 19 and 23%, respectively. These data indicated that isoforms of PML-RARA fused transcripts affect neither the clinical features of APL nor the prognosis after treatment with ATRA.

Adolescent↗

PubMed1995

[Penetrating keratoplasty for keratoconus in a case of Down's syndrome].

We report a Down's syndrome patient who underwent penetrating keratoplasty (PKP) surgery. The patient was a 62-year-old female who had Down's syndrome with severe bilateral keratokonus and cataract. Her visual acuity was very poor as she did everything by touch before the surgery. We performed a triple procedure surgery, i.e., PKP, extracapsular cataract extraction, and posterior chamber intraocular lens implantation in her left eye. After the surgery her visual behavior improved markedly. This case shows that PKP surgery can be performed on such handicapped patients who are difficult handle in emergencies and need general anesthesia, because we have been able to keep the donor cornea longer than usual. We conclude that we should actively perform the PKP surgery for the handicapped if the patient does not have self-damaging behavior and if there is cooperation of the family and the medical staff.

Down Syndrome↗

PubMed1995

Migration of donor cells into the thymus is not essential for induction and maintenance of systemic tolerance after liver transplantation in the rat.

In this study, we show that cells encoded by donor-type major histocompatibility complex (MHC) class I antigens effectively migrate into the thymus of the host after liver transplantation. However, the thymus is not essential for the induction and maintenance of tolerance after orthotopic rat liver transplantation (OLT). Liver allografted rats in the DA(RT1a) into PVG (RT1c) combination survived without immunosuppressive agents. The thymus of the host showed a transitory atrophy and returned to normal weight 4 weeks after OLT. Donor antigens were detected in the host thymus after OLT. Adult PVG rats that had been thymectomized 1 week before implantation of DA liver grafts showed liver graft survival without immunosuppression. DA heart grafts were heterotopically transplanted into the PVG thymectomized, liver-grafted rats 1-4 weeks after OLT. No rejection of the cardiac allografts was observed. Systemic tolerance was induced and maintained in the absence of the thymus.

Animals↗

PubMed1995

[Comparison of MICs of new quinolones obtained using agar-dilution and broth-microdilution procedures].

Minimum inhibitory concentrations (MIC) of new quinolones against both Gram-positive and Gram-negative bacteria obtained using agar-dilution and broth-microdilution procedures were compared. A primary regression curve and a correlation coefficient (r) between 2 MICs for each of ofloxacin, ciprofloxacin, tosufloxacin, sparfloxacin or balofloxacin were calculated. For the 5 quinolones, average correlation coefficients were 0.891 for the Gram-positive bacteria tested, and 0.865 for the Gram-negative bacteria. The range of, correlation coefficients for the Gram-positive bacteria for these drugs was from 0.835 to 0.919, and that for the Gram-negative bacteria was from 0.815 to 0.865. From these data, it is clear that there is a good correlation between the 2 MICs of the new quinolones obtained using the agar-dilution and the broth-microdilution procedures. It was also shown that the value of the slope of the regression curves were nearly the same for the 5 quinolones tested. However, some particular strains of Morganella morganii, Pseudomonas cepacia, Xanthomonas maltophilia, Pseudomonas aeruginosa and Streptococcus pneumoniae exhibited different correlation coefficients from other strains.

Bacteria↗

PubMed1995

Immunostaining for calcineurin, a Ca2+/calmodulin-regulated protein phosphatase, in the diagnostic tumor pathology.

The present immunochemical study concerns the distribution of calcineurin (CaN), a Ca2+/calmodulin-regulated protein phosphatase, in the nervous and neuroendocrine systems of mammals, and discloses the CaN-immunostaining results of human neoplasms. CaN immunoreactivity (ir) was present throughout the nervous system with a marked regional variation in strength of the staining intensity. Light microscopic observations showed that CaN-ir was localized in neurons, but was not detected in non-neuronal cells including astrocytes. Ultrastructural study also revealed that CaN-ir was present only in neuronal elements such as somata, dendrites including postsynaptic densities and spines, and nerve terminals. CaN-ir was also detected in neuroendocrine cells of some endocrine tissues including the pineal gland, pituitary gland, adrenal grand, pancreas and thyroid gland. Immunostaining results of 107 surgical specimens of human neoplasms, including 9 cases of peripheral tumors, disclosed that CaN-immunopositive tumor cells were found to be present in the neuronal tumors including neuroblastomas, ganglioglioma, ganglioneuroma, ganglioneuroblastoma, retinoblastomas, medulloblastomas and central neurocytomas. Also, some neuroendocrine tumors, such as pineocytomas, olfactory neuroblastomas and paragangliomas, specifically reacted for anti-CaN antibody. On the basis of these immunochemical findings, we have proposed that CaN can be a marker protein for detection of neuronal and neuroendocrine tumor cells in the diagnostic pathology of human neoplasms.

Animals↗

PubMed1995