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Biomedical subjects

I Sakamoto

Publications and source records attributed to I Sakamoto.

At least 37 records · Page 2Linked to original sources
PubMed2000

Practical synthesis of the disaccharide epitope, D-galactopyranosyl-alpha-1,3-D-galactopyranose, by using 1,2;5,6-di-O-cyclohexylidene-alpha-D-galactofuranose as the glycosyl acceptor.

D-Galactosyl-alpha-1,3-D-galactopyranose (1) was chemically prepared in a good yield by coupling phenyl 2,3,4,6-tetra-O-benzyl-1-thio-beta-D-galactopyranoside (5) or 2,3,4,6-tetra-O-benzyl-alpha-D-galactopyranosyl bromide (8) with 1,2:5,6-di-O-cyclohexylidene-alpha-D-galactofuranose (3) with subsequent de-O-benzylation and de-O-cyclohexylidenation of the resulting protected alpha1,3-disaccharide.

Carbohydrate Conformation↗
PubMed2000

Aortic aneurysms in patients with Takayasu's arteritis: CT evaluation.

OBJECTIVE: The objective of this study was to evaluate the incidence, development, and outcome of aortic aneurysm on CT in a group of patients with Takayasu's arteritis. MATERIALS AND METHODS: We reviewed the files of 31 patients with Takayasu's arteritis between January 1990 and March 1999. All patients were followed up for more than 6 months with CT, and the mean follow-up period was 52.9 months (median, 36.0 months). In all patients, initial CT was performed within 6 months of diagnosis of Takayasu's arteritis. The study group comprised 24 female patients and seven male patients; their ages at the first CT examination ranged from 8 to 72 years (mean, 42. 6 +/- 16.5 years). RESULTS: Seventeen aortic aneurysms were found in 14 (45.2%) of the 31 patients. Patients with severe calcification of the aorta showed significantly lower incidence of aneurysm formation than those without severe calcification of the aorta (p < 0.05). Of the 17 aneurysms, three were not present at the time of initial CT and appeared during the follow-up period. Nine of 17 aneurysms increased in size during the follow-up period. Three of the nine aneurysms rapidly increased in size and ruptured during the follow-up period. In all three of these aneurysms, aortic wall thickening was identified on CT. The remaining six aneurysms slowly increased in size but did not rupture. CONCLUSION: Aortic aneurysm associated with Takayasu's arteritis is not rare. The aorta with little calcification has a greater possibility of aneurysm formation in patients with Takayasu's arteritis. Aortic aneurysms with wall thickening can have fatal consequences.

Adult↗
PubMed2000

[Radiation-induced squamous cell carcinoma of the chest wall seven years after adjuvant radiotherapy following the surgery of breast cancer: a case report].

A 54-year-old woman, who had underwent an adjuvant radiotherapy following the modified radical mastectomy in the left primary breast cancer in June 1988. She underwent second surgery and adjuvant radiotherapy (electronic radiotherapy) for recurrent breast cancer in the major pectoral muscle and received chemoimmunotherapy in May 1989. In May 1996 she complained of two ulcers of the chest wall. The ulcer biopsy findings was squamous cell carcinoma, and we diagnosed she fell the radiation-induced skin cancer. She underwent chest wall resection and reconstruction with vertical rectal abdominal musculocutaneous flap (VRAM). However two months later her chest wall resection, she again got the recurrent squamous cell carcinoma in the right axillary lymph nodes and left pleura. The third radiotherapy and the chemotherapy with pepleomycin were uneffective on her recurrent cancer. And she died in March 1997.

Breast Neoplasms↗
PubMed1999

Refractory hepatic hydrothorax treated with transjugular intrahepatic portosystemic shunt.

A 66-year-old cirrhotic woman was referred to our hospital for evaluation of refractory pleural effusion and dyspnea. Massive right sided-pleural effusion but no ascites was detected. She had been treated with diuretics and albumin, repeated thoracenteses, and pleural drainage with an intercostal catheter, all of which had failed to relieve her symptoms. The diagnosis of hepatic hydrothorax without ascites was made by injection of technetium-99m-sulfur colloid into the peritoneal cavity. A transjugular intrahepatic portosystemic shunt was placed and successfully reduced the pleural effusion, resulting in complete relief of her symptoms. The patient has been free of symptoms for 18 months after the procedure.

Aged↗
PubMed1999

Clinical efficacy and indication of acetazolamide treatment on sleep apnea syndrome.

The efficacy and indication of acetazolamide treatment on patients with sleep apnea syndrome (SAS) were discussed from assessing the changes of polysomnographic findings with the treatment in 75 SAS patients. For the patients as a whole, respiratory disorder variables improved significantly during the treatment. However, the number of acetazolamide treatment responders who showed a decrease of apnea hypopnea index (AHI) to 50% or less of the pretreatment value numbered only 34 (45.3%). The lower values of body mass index and AHI in the responder group indicated that monotherapy with acetazolamide is the treatment choice only for mild SAS cases without obesity. However, combined treatment with acetazolamide and uvulopalatopharyngoplasty was thought to be beneficial for severe cases.

Acetazolamide↗
PubMed1999

Aortoiliac and lower extremity arteries: comparison of three-dimensional dynamic contrast-enhanced subtraction MR angiography and conventional angiography.

PURPOSE: To determine the clinical feasibility of three-dimensional dynamic contrast agent-enhanced subtraction magnetic resonance (MR) angiography in patients with symptoms of lower extremity ischemia. MATERIALS AND METHODS: Twenty-three patients suspected of having lower extremity ischemia underwent three-dimensional dynamic contrast-enhanced subtraction MR angiography of the aortoiliac arteries and arteries of the lower extremity. As the reference standard, conventional angiography was also performed. For data analysis, the arterial system was divided into 10 segments. Each segment was classified as normal, mildly stenosed, moderately stenosed, severely stenosed, or occluded. RESULTS: At conventional angiography, 83 stenosed segments (14 mildly stenosed, 16 moderately stenosed, 14 severely stenosed, and 39 occluded) were identified in a total of 423 segments. For the segments with more than mild stenosis, MR angiography was 97.1% sensitive and 99.2% specific. CONCLUSION: Three-dimensional dynamic contrast-enhanced subtraction MR angiography has high sensitivity and specificity. This technique is a noninvasive alternative to conventional angiography for screening patients suspected of having lower extremity ischemia.

Aged↗
PubMed1999

Malignant pheochromocytoma with multiple hepatic metastases treated by chemotherapy and transcatheter arterial embolization.

A 62-year-old Japanese male developed multiple hepatic metastases two years after resection of pheochromocytoma of the right adrenal gland. Transcatheter arterial embolization (TAE) was performed for the purpose of the treatment of hepatic metastases resistant to 27 cycles of combined chemotherapy consisting of cyclophosphamide, vincristine, and dacarbazine. After TAE, the hepatic metastatic lesions decreased in size and hypertension passed its crisis. The present case suggests the utility of TAE for multiple hepatic metastases under careful blood pressure monitoring.

Adrenal Gland Neoplasms↗
PubMed1998

Axin, a negative regulator of the wnt signaling pathway, directly interacts with adenomatous polyposis coli and regulates the stabilization of beta-catenin.

The regulators of G protein signaling (RGS) domain of Axin, a negative regulator of the Wnt signaling pathway, made a complex with full-length adenomatous polyposis coli (APC) in COS, 293, and L cells but not with truncated APC in SW480 or DLD-1 cells. The RGS domain directly interacted with the region containing the 20-amino acid repeats but not with that containing the 15-amino acid repeats of APC, although both regions are known to bind to beta-catenin. In the region containing seven 20-amino acid repeats, the region containing the latter five repeats bound to the RGS domain of Axin. Axin and beta-catenin simultaneously interacted with APC. Furthermore, Axin stimulated the degradation of beta-catenin in COS cells. Taken together with our recent observations that Axin directly interacts with glycogen synthase kinase-3beta (GSK-3beta) and beta-catenin and that it promotes GSK-3beta-dependent phosphorylation of beta-catenin, these results suggest that Axin, APC, GSK-3beta, and beta-catenin make a tetrameric complex, resulting in the regulation of the stabilization of beta-catenin.

Adenomatous Polyposis Coli Protein↗
PubMed1998

Changes in cyclin B during oocyte maturation and early embryonic cell cycle in the newt, Cynops pyrrhogaster: requirement of germinal vesicle for MPF activation.

When full-grown oocytes of the newt Cynops pyrrhogaster were treated with progesterone in O-R2 solution containing antibiotics, approximately 85% of the oocytes completed meiosis synchronously. Maturation-promoting factor (MPF) activity appeared just before germinal vesicle breakdown (GVBD) and the oocytes maintained high MPF activity throughout metaphase I and metaphase II of meiosis. A slight decrease of MPF activity was observed at the first polar body emission. The distribution of cyclin B1 was investigated with anti-cyclin B1 antibody. No cyclin B1 was found in the oocytes before progesterone treatment. Cyclin B1 appeared in the cortex of animal hemispheres, especially around and inside germinal vesicle just before GVBD. A large amount of cyclin B1 accumulated at metaphase I, approximately half disappeared at the first polar body emission, and then cyclin B1 accumulated again at metaphase II. An inactive form of cdc2 kinase was observed in both the germinal vesicles and the oocyte cytoplasm, while an active form appeared at the M phase. No MPF was observed in the oocytes from which the germinal vesicle had been removed. A cdk7-like molecule was localized in the germinal vesicle, but not in oocyte cytoplasm, indicating that inactive cdc2 kinase associated with cyclin B1 derived from cytoplasm is activated by phosphorylation in the germinal vesicle. The changes in the amount of cyclin B1 were synchronous with the first cell cycle after fertilization. Cyclin B1 was primarily localized in the cortex of the animal hemisphere. A shift in band mobility upon electrophoresis of cyclin B1 was observed from samples taken during the cell cycle; this shift was probably due to the protein's phosphorylation state.

Animals↗
PubMed1998

Abscopal regression of hepatocellular carcinoma after radiotherapy for bone metastasis.

Spontaneous regression of hepatocellular carcinoma is a rare phenomenon. Abscopal regression of tumours resulting from the effect of irradiation of a tissue on a remote non-irradiated tissue is also rare. The case of a 76 year old Japanese man with hepatocellular carcinoma that regressed after radiotherapy for thoracic vertebral bone metastasis is described. Serum levels of tumour necrosis factor-alpha increased after radiotherapy. The findings suggests that such abscopal related regression may be associated with host immune response, involving cytokines such as tumour necrosis factor-alpha.

Aged↗
PubMed1998

[Relationship between aging and morphological bone changes of the condyle in temporomandibular disorders].

In order to clarify the clinical significance of morphological bone changes of the mandibular condyle in temporomandibular disorders, the relationship between radiographic bone changes and aging was clinically studied. The subjects of the study were 1,120 patients (812 females and 308 males). The average age was 33 years +/- 15 years (from 10 to 81 years of age). The 1,120 patients were divided into six age brackets (10 to 19 years, 20 to 29 years, 30 to 39 years, 40 to 49 years, 50 to 59 years, 60 to 81 years). According to radiograms taken by lateral oblique transcranial projection, orbitcondyle projection and orthopantomography, the morphological bone changes were classified into seven groups, erosion, osteophyte, eburnation, flattening, deformity, concavity and sclerosis. The results were as follows: 1. The incidence of the patients with radiographic bone changes of the mandibular condyle increased with aging and showed significantly different age distribution from that without bone changes (Mann-Whitney U test: p < 0.01). 2. The incidence of erosion did not increase with aging and showed significantly different age distribution from osteophyte or eburnation (Mann-Whitney U test: p < 0.01, 0.05). The incidence of flattening also did not increase with aging and showed significantly different age distribution from osteophyte, eburnation or deformity (Mann-Whitney U test: p < 0.01, 0.05, 0.05).

Adolescent↗
PubMed1997

Combined intraarterial chemotherapy and radiotherapy in the treatment of bladder carcinoma.

BACKGROUND: The combination of radiotherapy and cisplatin-based chemotherapy has proved to be an effective treatment for bladder carcinoma in many clinical studies. Intra-arterial approaches to chemotherapy have been developed to reduce systemic toxicities and improve response rates. This study was designed to determine the effectiveness of intra-arterial chemotherapy with cisplatin and doxorubicin combined with radiotherapy in the treatment of patients with invasive bladder carcinoma. The objectives were to evaluate the response rate, bladder preservation rate, toxicity, and survival rate. METHODS: Thirty-five patients with muscle-invasive bladder carcinoma at clinical stage T2-T4N0M0 were each treated with 2courses of intra-arterial cisplatin and doxorubicin at 3-week intervals, whereas radiotherapy was administered for 4 weeks (2 gray [Gy] given a total of 20 times, at 5 fractions per week). Patients with complete responses were given an additional course of chemotherapy (intra-arterial cisplatin and doxorubicin) and irradiation (20 Gy), and patients with residual tumor after the initial chemoradiotherapy underwent cystectomy. RESULTS: A clinical complete response was observed in 26 patients (74%; 95% confidence interval, 59-89%), and an incomplete response was observed in 9 (26%; 95% confidence interval, 11-41%). The bladder was preserved in all patients with a complete response, and it was tumor free in 19 of them (54% of all patients). The actuarial survival rate was 76.6% at 5 years. After a median follow-up interval of 45 months, 28 patients (80%) were alive and 7 (20%) had died due to disease progression. The regimen was well tolerated, with no severe systemic or local toxicities. CONCLUSIONS: The high rates of response, survival, and bladder preservation observed indicate that this combined intra-arterial chemotherapy and radiotherapy regimen would be useful in the management of invasive bladder carcinoma. This was a small Phase II trial; the results are preliminary, and the utility of this treatment modality in patient management remains to be proven.

Adult↗
PubMed1997

Transarterial infusion of cisplatin and doxorubicin in bladder cancer.

Forty-five patients (median age 63 years) with muscle invasive bladder cancer were treated with transcatheter intraarterial infusion (TAI) of cisplatin (CDDP) and doxorubicin. They received a total of 114 courses (median 3 courses per patient) of TAI. Complete response was obtained in 20 patients (44%), partial response in 17 (38%), stable disease in 6(13%), and progression of disease in 2 patients (5%). The overall response rate was 82% at a median follow-up of 36 months. The actuarial survival of the patient population was 72% at 5 years; 36 patients were alive and 9 had died of cancer progression. The treatment was generally extremely well tolerated without major complications. The current study also revealed the fact that papillary carcinomas were more sensitive to this therapy than were non-papillary tumors. Overall, response rate and local control were significantly higher in low-grade than in high-grade tumors. The observed high complete response and good survival rate suggest that intraarterial CDDP and doxorubicin might be highly effective for localized invasive bladder cancer.

Adult↗
PubMed1997

[Observations on structure of bone in human mandibular condyles with osteophyte formation].

The purpose of this study was to investigate the functional characteristics of human mandibular condyles from a morphological viewpoint. The structure of bone in the human mandibular condyles with osteophyte formation was observed macroscopically and microscopically and compared with that in the condyles which seemed to be normal. The following observations were made: 1. Generally, it was observed that remodeling seemed to occur frequently in compact bone in the joint surface area of the mandibular condyle. 2. As the distribution of lamellar bone, nonlamellar, and bundle bone in the joint surface area changes, the compact bone seems to shift down and protrude forward. In larger osteophytes, trabeculae of cancellous bone-like structure are observed. However, the basic structure of compact bone, including haversian system and the interlamellae structure remains within the trabecullae. Therefore, observation revealed histologically that this is a compact bone. The macroscopical appearance of cancellous bone-like structure seems to be a result of functional demand. 4. It was concluded that the mandibular condyles accommodate the functional loads, and adoptational changes occur constantly in a stable manner.

Adult↗