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Biomedical subjects

I Sekine

Publications and source records attributed to I Sekine.

At least 127 records · Page 7Linked to original sources
PubMed1997

Evaluation of tapered-end toothbrushes regarding subgingival access efficacy.

The purpose of this in vitro study was to determine how two toothbrushes with highly tapered-end bristle designs compared to a conventional, slightly tapered toothbrush. Toothbrushing was carried out in the laboratory in order to evaluate the simulated subgingival efficacy of the three toothbrush designs. The performance of the three brushes was assessed by measuring the "subgingival regions" of gold-coated typodont left maxillary central teeth where the gold coating had been removed during brushing. The two toothbrushes with highly tapered bristles were statistically significantly (p < 0.01) more effective in removing the gold coating than the conventional toothbrush with slightly tapered bristles on the subgingival area on the anterior typodont teeth.

Analysis of Variance↗
PubMed1996

Incidence of intracranial meningiomas in Nagasaki atomic-bomb survivors.

Among the Nagasaki atomic-bomb survivors registered at the Scientific Data Center for Atomic-Bomb Disaster, Nagasaki University School of Medicine, 45 cases of surgically treated intracranial meningioma were collected from 6 hospitals with departments of neurosurgery in or near Nagasaki City during the period from 1973 to 1992. All 45 patients were over 40 years of age at the time of diagnosis. Subsequently, the 45 cases were statistically analyzed in relationship to the estimated distance from the hypocenter by age, gender, intracranial location, histology and latent period. The analysis showed a high correlation between incidence of meningiomas and distance from the hypocenter. The incidence among Nagasaki atomic-bomb survivors over 40 years of age, especially in those proximally exposed, appears to be increasing, in inverse proportion to the exposure distance, since 1981, 36 years after the explosion of the atomic bomb.

Adult↗
PubMed1996

Efficacy of interferon in treating chronic hepatitis C in children with a history of acute leukemia.

Interferon (IFN) is effective in treating adults as well as children with chronic hepatitis C. We investigated the efficacy of IFN therapy in 13 children with underlying acute leukemia who had chronic hepatitis C (age range, 5 to 17 years; mean age, 9.9 years). Natural IFN- alpha was administered at a dose of 0.1 mega unit (MU)/kg (maximum dose, 6.0 MU) daily for 2 weeks and then three times per week for an additional 22 weeks (total dose, 8 MU/kg). IFN treatment was initiated at least 2 years after the completion of treatment for acute leukemia. A complete response was obtained in 5 children (38%). The serum level of anti-hepatitis C virus core antibody was closely related to the response to IFN. IFN therapy was well tolerated by all but 1 of the children, who developed mild transient heart failure 4 months after the initiation of therapy. IFN therapy for children with chronic hepatitis C who had underlying acute leukemia was beneficial. However, further trials are required to confirm the safety and improve the dosage schedule of IFN therapy.

Acute Disease↗
PubMed1996

Three cases of hereditary nonspherocytic hemolytic anemia associated with red blood cell glutathione deficiency.

Three unrelated Japanese patients with chronic nonspherocytic hemolytic anemia wer found to have marked deficiency of red blood cell (RBC) reduced glutathoine (GSH) (4.4%, 13.1%, and 6.9% of normal, respectively). A panel of RBC enzyme assays showed that one patient had decreased glutathione synthetase activity and the other two were moderately deficient in gamma-glutamylcystine synthetase. Some family members of each patient showed mild deficiency of the respective enzymes. RBCs of these patients also showed a decreased level of glutathione-S-transferase as in previously described GSH-deficient cases. Hemolytic anemia was their only manifestation, and neither 5-oxoprolinemia nor 5-oxoprolinuria, which are usually associated with to generalized type of glutathione synthetase deficiency, was noted in our patients.

Adolescent↗
PubMed1996

Histopathological characteristics of childhood thyroid cancer in Gomel, Belarus.

We reviewed histopathologically 19 cases of childhood thyroid cancer occurring between 1991 and 1994 among 14,396 screening subjects in Gomel, Republic of Belarus, the region most severely radio-contaminated by the Chernobyl nuclear power plant accident in 1986. The patients were 13 girls and 6 boys with a mean age of 10.6 years. The mean age at the time of the accident was 3.2 years. Mean tumor diameter was 16 mm, and all cases were papillary carcinoma with various amounts of solid component. Psammoma bodies and stromal fibrosis were encountered to some extent in almost all cases. The tumors were highly prone to local invasion and regional lymph-node metastasis. No morphological evidence for radiation-induced cancer was obtained in these cases. 137Cs levels were relatively high in the patients' bodies and in the soil at the places of domicile. However, there was no dose-response relationship between cancer prevalence and radioactivity. These facts suggest that the incidence of aggressive pediatric thyroid cancer is extremely high in Gomel, where most of the children were exposed to a low level of radioactivity over a long time after the accident. At present, however, no definite conclusion can be drawn on the relationship between cancer occurrence and radioactive contamination.

Accidents↗
PubMed1996

Expression of parathyroid hormone (PTH)-related peptide (PTHrP) and PTH/PTHrP receptor in giant cell tumour of tendon sheath.

The giant cell tumour of tendon sheath (GCTTS) is mainly composed of mononucleated stromal cells (SC) and multinucleated giant cells (GC), so-called osteoclast-like GC. It is thought that GC are derived from SC, but their precise relationship is not fully understood. Parathyroid hormone (PTH)-related peptide (PTHrP) is now considered to be a cytokine for cell differentiation, which may stimulate osteoclast-like cell formation in haematopoietic cells. Five cases of GCTTS were evaluated immunohistochemically, using a variety of antibodies against PTHrP, PTH/PTHrP receptor, KP-1 as a histiocytic phenotypic antigen, fibronectin as a fibroblastic phenotypic antigen, and proliferating cell nuclear antigen (PCNA). In situ hybridization and immunohistochemistry revealed that in all cases both SC and GC expressed PTHrP. PTH/PTHrP receptor was observed only in histiocytic SC and GC, but not in fibroblastic SC. Almost all GC showed histiocytic features. PCNA immunoreactivity was detected only in the nuclei of SC, and not in GC. Moreover, SC with PTH/PTHrP receptor immunoreactivity were negative for PCNA. These results suggest that GC are derived from histiocytic SC expressing PTH/PTHrP receptor and losing proliferative activity in the process of transition from mononuclear to multinucleated. PTHrP produced by SC and GC may be involved in the formation of osteoclast-like cells in GCTTS by acting in an autocrine/paracrine fashion.

Gene Expression↗
PubMed1996

Autopsy case of colocalized tumors of hepatocellular carcinoma and malignant lymphoma.

We present a rare case of colocalized tumors of hepatocellular carcinoma (HCC) and malignant lymphoma in the liver and bone marrow. A 64-year-old man with hepatitis B virus (HBV)-induced cirrhosis was admitted after detection of elevated serum alpha-fetoprotein level. He was diagnosed as having HCC and treated with chemotherapy and radiotherapy, but the size of the tumors did not diminish. After 11 months' hospitalization, he died due to rupture of esophageal varices. Autopsy revealed two heterogenic malignant tumors, HCC and malignant lymphoma (B cell type), in the liver. These tumors showed colocalization in the liver and bone marrow. The carcinogenetic process of colocalized tumors of HCC and lymphoma was not clarified, but the possibility that persistent HBV infection play a role in promoting hepatocarcinogenic and hematopoietic tumor growths in the reticuloendothelial organs could not be excluded.

Autopsy↗
PubMed1996

Carcinoma in gastric hyperplastic polyps. A phenotypic study.

One-hundred twelve hyperplastic polyps were analyzed. The aim was to study their malignant transformation. Among them, four hyperplastic polyps harbored adenocarcinoma; two were from our own institution (1.8%). The majority were pedunculated and located in the antrum with an average of 14.5 mm in diameter. The four polyps bore well-differentiated adenocarcinoma. Dysplasia and intestinal metaplasia were detected in two and three polyps, respectively. The cancer and dysplastic foci shared the same type of neutral and acid mucosubstances. p53 oncoprotein was positive in three cancer foci and in the dysplastic areas, and nucleolar organizer region counts were higher in the cancer foci. In conclusion, hyperplastic polyps have malignant potential. Such possibility increases in polyps larger than 14.5 mm. In our cases, the carcinoma foci may have arisen from dysplastic areas. Once the neoplastic changes occur, the cancer cells proliferate and behave as other adenocarcinomas of the stomach.

Adenocarcinoma↗
PubMed1996

A randomized cross-over trial of granisetron and dexamethasone versus granisetron alone: the role of dexamethasone on day 1 in the control of cisplatin-induced delayed emesis.

We studied the role of dexamethasone (DEX) administered on day 1 in controlling cisplatin-induced delayed emesis. Forty patients were randomly allocated to receive either granisetron (GRN) and DEX on day 1, or the same dose of GRN alone. On days 2-5, all the patients received metoclopramide and DEX. They were crossed over to the other antiemetic regimen with their second course of chemotherapy. Thirty-one patients were evaluable for efficacy. The mean visual analogue scale scores for nausea on days 1 and 2 were 9.1 and 18.8 mm for GRN and DEX, and 16.3 and 28.5 mm for GRN alone, respectively (P<0.05 on day 2). The mean numbers of emetic episodes on days 1-3 were 0.036, 0.46 and 0.36 for GRN and DEX, and 0.39, 0.89 and 0.57 for GRN alone, respectively (P<0.01 on day 1). Hiccups and restlessness were noted in 38% and 33% of cycles, respectively. Addition of DEX to GRN on day 1 thus enhanced the control of delayed emesis.

Adult↗
PubMed1996

Recurrent breast cancer treated successfully with mitomycin-C and vinblastine after failure of both doxorubicin-containing regimen and paclitaxel--a case report.

Cross-resistance is one of the chief obstacles in salvage therapy for refractory breast cancer. Although paclitaxel is one of the most promising drugs, it shows a response rate of 30% at most for patients with breast cancer resistant to doxorubicin, and no effective treatments for tumors refractory to both agents have been reported. We describe a 38-year-old woman with recurrent breast cancer, who was treated successfully with mitomycin-C and vinblastine after doxorubicin-based chemotherapy and paclitaxel failed. The combinations of mitomycin-C and microtubule inhibitors including vinca alkaloids and taxanes may have a potential application to refractory breast cancer.

Adenocarcinoma, Scirrhous↗
PubMed1996

Impairment of antioxidants in colonic epithelial cells isolated from trinitrobenzene sulphonic acid-induced colitis rats. Protective effect of rebamipide.

BACKGROUND: The functional status of glutathione, its related enzymes, and Cu,Zn-superoxide dismutase in colonocytes isolated from rats with trinitrobenzene sulphonic acid-induced colitis, and the effect of rebamipide (a scavenger) on these antioxidants and on colitis, were studied. METHODS: The rats were treated with rebamipide, killed on day 14, and compared with controls. Glutathione and enzymatic activities were spectrophotometrically estimated. The effect of rebamipide on colitis was also assessed histologically and by myeloperoxidase activity. RESULTS: In controls the concentration of glutathione and the activities of glutathione S-transferase and Cu,Zn-superoxide dismutase were decreased, but that of glutathione peroxidase was increased. Rebamipide prevented the impairment of these enzymes, restored the concentration of glutathione, and attenuated (low damage scores and myeloperoxidase activity) the severity of the colitis. CONCLUSIONS: These features suggest that the impairment of antioxidants is closely related to the development of the inflammatory lesions, and rebamipide has a beneficial effect on experimental colitis.

Alanine↗
PubMed1996

Roentgenographically occult small-cell lung cancer: case report and review of the literature.

This report describes a rare case of roentgenographically occult small-cell lung cancer in a 73-year-old man with hemoptysis. Fiberoptic bronchoscopy disclosed a 5-mm dome-shaped lesion; a biopsy established the diagnosis of small-cell lung cancer. The patient received a combination of chemotherapy and radiotherapy. More than 10 years later, he is still alive without recurrent disease. A review of the literature of roentgenographically occult small-cell lung cancer revealed the following: (1) a history of heavy smoking was common; (2) double primary bronchogenic carcinoma was noted; (3) hemoptysis or bloody sputum was an initial common symptom; (4) the sensitivity of sputum cytologic analysis was relatively low; (5) the tumor, which was shiny, smooth, and covered with bronchial epithelium, was often located at the bifurcation; and (6) lymph node metastatic involvement occurred.

Aged↗
PubMed1996

Expression of the Ets-1 proto-oncogene in human gastric carcinoma: correlation with tumor invasion.

The proto-oncogene Ets-1 is a transcription factor known to control the expression of a number of genes involved in extracellular matrix remodeling and has been postulated to play a role in cell migration and tumor invasion. To elucidate the involvement of Ets-1 in human gastric carcinomas, we examined 11 cases of gastric adenoma and 110 cases of gastric carcinoma by immunohistochemistry and compared the degree of Ets-1 expression with the depth of carcinoma invasion. Ets-1 was not expressed either in the normal gastric epithelium or in gastric adenomas. Among the 110 cases with gastric adenocarcinoma, 70 (63.6%) showed positive staining for the Ets-1 protein. In mucosal carcinomas, only 3 of 26 cases (11.5%) showed positive immunostaining for Ets-1. In contrast, 67 of 84 cases (79.8%) with submucosal or more invasive carcinomas showed immunopositivity and intense staining for Ets-1 in the tumor cells. The pattern of Ets-1 immunostaining in mucosal carcinomas was weak and differed from that of other local invasive carcinomas (P < 0.001). Histologically, signet-ring cell and mucinous carcinomas expressed relatively weak positivity for Ets-1. Ets-1 expression correlated significantly with the presence of lymph node metastasis (P < 0.001). In situ hybridization, using an Ets-1 oligonucleotide probe, also confirmed the presence of Ets-1 mRNA in gastric carcinomas. Expression of Ets-1 mRNA was also detected in four different kinds of cultured human gastric carcinoma cell lines by the reverse transcription polymerase chain reaction method. These findings suggest that Ets-1 is overexpressed in gastric mucosal cells that have undergone malignant conversion and that Ets-1 is one of the factors involved in the penetration of gastric carcinoma beyond the muscularis mucosa.

Adenocarcinoma↗
PubMed1996

Phase II study of 3-hour infusion of paclitaxel in previously untreated non-small cell lung cancer.

Paclitaxel has clinical activity in non-small cell lung cancer, with response rates of 21 and 24% in a 24-h infusion. Recent clinical studies have shown that a 3-h infusion of the drug with premedication did not result in hypersensitivity reactions, and that neutropenia was milder in the 3-h than in the 24-h schedule. In this Phase II study, we tried to evaluate the efficacy and toxicity of paclitaxel given over 3 h in patients with previously untreated, unresectable stage III or IV non-small cell lung cancer. In addition, we attempted to investigate the pharmacokinetics and pharmacodynamics of the drug. Paclitaxel was administered i.v. over 3 h at a dose of 210 mg/m2 every 3 weeks with premedication of dexamethasone, ranitidine, and diphenhydramine. Heparinized blood samples were obtained from 12 patients for pharmacokinetic studies. Twenty-three (38%) of 60 assessable patients achieved a partial response, with a median duration of 3.2 (range, 2.3-11.1) months. The median survival for all patients was 11.2 months, and the 1-year survival rate was 48%. Thirty (50%) patients developed grade 4 neutropenia. Nonhematological toxicities were mild, except for pulmonary toxicity in one (1.7%) patient who required mechanical ventilatory support for 4 days. The duration of the paclitaxel concentration above 0.1 microM correlated well with the percentage of decrease in the absolute neutrophil count. In conclusion, a 3-h infusion of paclitaxel was safe and probably not less effective than a 24-h infusion.

Adult↗
PubMed1995

Inhibition of epidermal growth factor binding system by ionizing radiation in A431 human squamous carcinoma cells.

To elucidate the effect of ionizing radiation on the membrane anchored signal transduction, the binding of 125I epidermal growth factor (EGF) to its receptor (EGF-R) and the EGF-dependent EGF-R tyrosine phosphorylation were examined in a human squamous cell carcinoma cell line, A431. The significant suppression of 125I EGF binding to A431 cells was observed from 3-5 h after 10 Gy irradiation, whereas this inhibition was not observed both in non-irradiated and in 5 Gy-irradiated cells. This phenomenon was mediated by the protein kinase C pathway, because the inhibition was not observed in cells which had been pretreated with phorbol ester and treated with an inhibitor of the enzyme, H7. Scatchard analysis showed that the receptor affinity was decreased. In contrast, the level of EGF-dependent EGF-R-tyrosine phosphorylation was not decreased, compared with non-irradiated cells. These results suggest that ionizing radiation may modulate the function of EGF/EGF-R interaction through the direct activation of protein kinase C.

Carcinoma, Squamous Cell↗
PubMed1995

Efficacy of flashlamp-pumped pulsed dye laser therapy for port wine stains: clinical assessment and histopathological characteristics.

Clinicopathological evaluation of flashlamp-pumped dye laser therapy for port wine stains was conducted on 474 subjects (135 male and 339 female) ranging in age from less than a year to 85 years (median = 17; lower quartile = 7 and upper quartile = 28). There was a significant variation in the rate of favourable response among lesion sites but the variation in relation to sex, age and radiation dose was not significant. Histological investigations of skin biopsy specimens from 23 subjects indicated that the mean depth of vessels is the main prognostic factor. The critical value (standard error) of the mean depth for a favourable response was estimated as 930(50) microns. Applications of this estimate to clinical prognosis are discussed.

Adolescent↗
PubMed1995

Clinical evaluation of the efficacy of EDTA solution as an endodontic irrigant.

The effect of eliminating the smear layer by means of 15% EDTA solution as a root canal irrigant was studied in 189 single-rooted infected teeth. Each tooth was treated at two appointments, and the root canal bacteriological examination was studied on the first (pretreatment, and after enlargement and irrigation) and second (pretreatment) visits. The root canals were irrigated with 15% EDTA solution with ultrasonics agitation. No antibacterial intracanal medications were used between the appointment. When 15% EDTA solution was used, no bacteria could be recovered from 93 of 129 root canals at the sampling stage on second visit. No bacteria were found in 21 of 60 root canals when saline solution was used as an irrigant. These results suggest that 15% EDTA solution is more effective than saline solution as a root canal irrigant.

Anti-Infective Agents, Local↗