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Biomedical subjects

Y Ogata

Publications and source records attributed to Y Ogata.

302 records · Page 17Linked to original sources

Downgraded non-Hodgkin's lymphoma in the neck occurring as a secondary malignancy.

While the histologic progression from low-grade non-Hodgkin's lymphoma (NHL) to intermediate- or high-grade NHL has been well documented, a rare phenomenon called downgrading in which the histologic conversion of a low-grade NHL occurs after treatment for intermediate- or high-grade NHL has recently been recognized. We report the clinical, immunologic, and genetic features of a patient with a diffuse NHL (intermediate grade) who initially achieved complete remission by both chemotherapy and radiation therapy and then presented with a follicular NHL (low grade) 14 years later. The immunohistochemical study of the lymphoma cells showed B lymphocytes in biopsied lymph nodes at both the initial and the second diagnosis. However, a polymerase chain reaction (PCR) analysis for the immunoglobulin gene rearrangement indicated that the clone of the initial intermediate-grade NHL showed monoclonal cell population, and was distinct from that of the second downgraded form. Given the PCR results and the clinical features, we suggest that a follicular NHL can occur as a secondary malignancy following combined therapy for a diffuse NHL.

Fatal Outcome↗

Isolated mucocele in an Onodi cell.

A rare case of retrobulbar optic neuropathy caused by an isolated mucocele in an Onodi cell is presented. A 63-year-old man suffering from left recurrent optic neuropathy had shown improved visual acuity with steroid treatment at the age of 48 and 56 years. Impaired visual acuity and blurred vision in the left eye appeared again, and a marked inferior decrease in the left visual field was noted. Although axial computed tomography (CT) showed no abnormal findings, magnetic resonance imaging (MRI) revealed a small squamous-shaped lesion (17 x 17 x 7.3 mm) in the left posterior ethmoidal air cell (Onodi cell) hanging over the left optic nerve. Endoscopic sinus surgery was performed. The optic canal was extruding into the Onodi cell cavity, and the superior bony wall of the canal was eroded by the mucocele. The isolated mucocele in the Onodi cell seemed to be compressing the optic nerve downward an causing retrobulbar optic neuropathy. An Onodi cell lesion, even if it was isolated and small, would cause optic neuropathy. MRI and coronal CT scanning should be performed for the diagnosis and preoperative planning in a case of retrobulbar optic neuropathy.

Endoscopy↗

Motility of vestibular hair cells in the chick.

Recent studies of the outer hair cells in cochlea have demonstrated active motilities. However, very little study has been done on the vestibular hair cells (VHCs). The present study shows the motile response of the VHCs induced by application of Ca2+/ATP promoting contraction. Reversible cell shape changes could be shown in 10 of 16 isolated type I hair cells and 9 of 15 isolated type II hair cells by applying the contraction solution. Furthermore, the sensory hair bundles in the utricular epithelium pivoted around the base and stood perpendicularly to the apical borderline of the epithelium in response to the application of the same solution. It is suggested that the contraction of the isolated VHCs may be transferred to tension which causes the sensory hair bundles to restrict their motion in normal tissue, instead of changing the cell shape.

Animals↗

Takayasu's arteritis with heart failure due to atherosclerosis.

An autopsy case of an elderly man with Takayasu's arteritis and atherosclerosis is presented. Ischemic signs and symptoms including anginal attack were aggravated with activity of arteritis despite administration of prednisolone throughout the entire course. The autopsy revealed severe atherosclerosis over the aorta and its branches, and arteritis in the fibrotic stage in localized area. Vessels of vital organs including heart and kidneys, did not show Takayasu's arteritis but were atherosclerotic. This case highlights the numerous problems encountered in the treatment of elderly patients with vasculitis such as Takayasu's arteritis.

Aged↗

Multiple gastric carcinoid tumors with type A gastritis concomitant with gastric cancer: a case report.

We describe a case with multiple gastric carcinoid tumors combined with early gastric carcinoma originated from the type A gastritis-affected tissue. Microcarcinoid foci were observed from the deeper layers of the propria mucosa to the submucosa and were surrounded by endocrine cell micronests (ECMs), while carcinoma was limited within the mucosa. Serum gastrin level was high (1,100 pg/ml) pre-operatively but returned to normal (44 pg/ml) post-operatively. It suggested that the longstanding hypergastrinemia may have played a causative role in the development of multiple carcinoids and cancer. Surgical treatment was considered essential for treatment in this case of coincident multiple carcinoid tumors and cancer.

Adenocarcinoma↗

Combined resection of the portal vein for pancreatic cancer: preoperative diagnosis of invasion by portography and prognosis.

BACKGROUND/AIMS: Pancreatic cancer often invades the portal vein because of the anatomical position. Pancreatic cancer with portal vein invasion was not considered operable, and thus the resectability rate was low. METHODOLOGY: Between March 1976 and February 1994, 140 of 243 patients underwent resection, a resectability rate of 58%. A total of 81 (58%) of these patients underwent portal vein resection. We assessed 56 patients in whom the depth of invasion had already been determined histopathologically and whose superior mesenteric arterial portograms were readable. The 56 patients were classified into 4 groups: normal (Type I), stricture on one side of the portal vein (Type II), stricture on both sides of the portal vein (Type III), complete obstruction (Type IV). The length of the longitudinal lesions on portograms was also measured. RESULTS: In 93% (27/29 cases) of portographic Type I or II lesions with longitudinal lesions of 2 cm or less, portal vein invasion was limited to the tunica media. No patients with cancer invasion into the lumen survived more than 1 year. CONCLUSIONS: For patients with pancreatic cancer Type I or II, preoperative portography findings and longitudinal lesions of 2 cm or less, portal vein resection is indicated, and long-term survival can be expected.

Adult↗

5-fluorouracil sensitivity and dihydropyrimidine dehydrogenase activity in advanced gastric cancer.

BACKGROUND: Dihydropyrimidine dehydrogenase (DPD) is the rate-limiting enzyme of 5-fluorouracil (5-FU) catabolism. Several studies have demonstrated the clinical importance of DPD in cancer patients, suggesting that the efficacy of 5-FU may be related to DPD activity in tumor tissue. In the present study, DPD activity and chemosensitivity to 5-FU were evaluated in advanced gastric cancer. MATERIALS AND METHODS: Thirty-four gastric cancers from 32 patients were studied and chemosensitivity to 5-FU was evaluated by histoculture drug response assay. RESULTS AND CONCLUSION: DPD activity and tumor inhibition of 5-FU among all cases showed no significant correlation, but among 14 histologically differentiated cases significant correlation was observed. DPD activity may be useful in determining the 5-FU sensitivity of differentiated gastric cancer.

Antimetabolites, Antineoplastic↗

p53, bcl-2 and thymidine phosphorylase as predictive markers of chemotherapy in patients with advanced and recurrent gastric cancer.

PURPOSE: To study the relationship between expression of p53, bcl-2, thymidine phosphorylase and Ki-67 and the response to chemotherapy and survival in patients with recurrent and advanced gastric cancer. MATERIALS AND METHODS: Protein expression was assessed immunohistochemically in 28 patients treated with 5-fluorouracil, pirarubicin and cisplatin (FAP). RESULTS: The response rate in patients positive for p53 expression was 23% compared with 47% of p53-negative patients. The response rate was also reduced from 44% in patients negative for bcl-2 protein expression to 25% in bcl-2 positive patients. Thymidine phosphorylase (dThdPase) expression was observed in 20 patients (71%), 50% of whom responded to chemotherapy, while patients negative for dThdPase expression did not respond to chemotherapy. The correlation between response rate and dThdPase-positivity was statistically significant (p < 0.05). However, with regard to patient survival, p53- and bcl-2-negative patients showed significantly better survival than patients positive for p53 and/or bcl-2 (p = 0.036). CONCLUSION: While dThdPase expression may be a useful predictor of response to chemotherapies that include 5-FU, p53 and bcl-2 expression may predict the outcome of patients with recurrent and advanced gastric cancer following chemotherapy.

Antineoplastic Combined Chemotherapy Protocols↗

Significance of para-aortic lymph node dissection in patients with advanced and recurrent gastric cancer.

Among 243 patients who underwent radical gastrectomy for advanced gastric cancer, 19 patients underwent radical gastrectomy with extended lymphadenectomy including cancer-positive para-aortic lymph nodes. Their prognosis was unexpectedly good, with a mean postoperative survival time of 24.1 months and a 2-year-survival rate of 42.4 percent. Another 4 patients developed para-aortic lymph node recurrence detected by computed tomographic scan during a follow-up examination. These 4 patients were treated with macroscopic curative dissection of the para-aortic lymph nodes. Although 2 of the 4 patients died within 6 months after re-operation, the prognosis of the other two patients was rather good when treated with active combination chemotherapy consisting of 5-fluorouracil, adriamycin and cisplatin. Dissection of para-aortic lymph nodes is considered of valuable in the treatment of advanced gastric cancer, and dissection of the para-aortic lymph node recurrence may also be valid when combined with potent chemotherapy.

Adult↗

5-FU-induced apoptosis correlates with efficacy against human gastric and colon cancer xenografts in nude mice.

Apoptosis may be an important mechanism by which cancer cells are killed by certain agents. It is reported here that apoptosis is a key event in the killing of human tumor cells by 5-fluorouracil (5-FU) in vivo. Apoptosis induced by 5-FU was determined using two human gastrointestinal tumor xenografts serially transplanted into nude mice: a gastric carcinoma (SC-1-NU) highly sensitive to 5-FU and a colon carcinoma (Co-4) less sensitive to 5-FU. Apoptosis was assayed using the terminal deoxynucleotidyl transferase (TdT)-mediated deoxyuridine triphosphate (dUTP)-biotin nick end labeling method in paraffin-embedded tissue sections, and by flow-cytometric analysis. Apoptosis-positive cells increased gradually during treatment. 24 hours after the initiation of 5-FU treatment a maximum, of 15.4% of the Co-4 cells were apoptotic. 48 hours after the initiation of 5-FU treatment, apoptosis was found in 34% of the tumor cells in the SC-1-NU strain. Flow-cytometry demonstrated the increase of S-phase fractions in both strains after the administration of 5-FU, and this coincided with the appearance of apoptotic-positive cells. Although the intrinsic. TS activities of two strains differed, TS activities were markedly suppressed in both strains immediately after the administration of 5-FU. Concentration of 5-FU in RNA (F-RNA) increased gradually in both strains, reaching a maximum 24 hours after the administration of 5-FU. These results suggest that apoptosis and inhibition of DNA synthesis induced by 5-FU are closely associated with its antitumor effect.

Animals↗

Immunocytochemical localization of calmodulin in the vestibular end-organs of the gerbil.

This study demonstrates the presence of calmodulin in the vestibular end-organs of the gerbil by use of immunocytochemistry. Using fluorescence microscopy, calmodulin was localized to the cytoplasm, cuticular plate, and stereocilia of both type I and type II hair cells in the sensory epithelia of the utricle and cristae ampullaris; no label was found in the supporting cells, the dark cells, or the nerve fibers. There was no immunoreactive distinction between the labeling of type I and type II hair cells in the striolar or extrastriolar regions. Thus, immunocytochemical labeling for calmodulin provides a good marker for hair cells in gerbil vestibular epithelium. The presence of calmodulin in the stereocilia was confirmed by immunoelectron microscopy using secondary antibodies coupled to colloidal gold.

Animals↗

Bcl-2 expression as a prognostic factor of survival of gastric carcinoma.

BACKGROUND: Although the bcl-2 proto-oncogene is important in determining tumor cell susceptibility to apoptosis, no data about the clinical importance in gastric cancer are available. METHODS: We analyzed bcl-2 and p53 expression, proliferative activity, and tumor apoptosis in locally advanced gastric carcinomas from 84 patients. RESULTS: Immunohistochemical analysis indicated that 41.7% and 48.8% of the tumors were bcl-2-positive, respectively. The apoptotic fraction was significantly lower in bcl-2-positive than negative tumors. Univariate analysis indicated low apoptotic fraction was one of the poor prognostic factors. Multivariate analysis showed a trend toward improved survival in bcl-2-positive patients. In patients with lymph node metastases more severe than group 2 lymph node, survival was significantly longer in those with bcl-2-positive tumors. CONCLUSIONS: The expression of bcl-2 and the high apoptotic fraction were concluded to be important prognostic factors of survival in patients with advanced gastric cancer.

Adenocarcinoma↗