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Biomedical subjects

Y Araki

Publications and source records attributed to Y Araki.

At least 55 records · Page 3Linked to original sources
PubMed2001

Epithelial expression of caveolin-2, but not caveolin-1, is enhanced in the inflamed mucosa of patients with ulcerative colitis.

Caveolae are vesicular invaginations of the plasma membrane that act as a scaffold of the assembly of many classes of signaling molecules. Caveolins are the principal structural component of caveolae membranes, and three distinct forms of caveolins have been identified: caveolin-1, caveolin-2, and caveolin-3. In this study, we evaluated the changes in the caveolin-1 and caveolin-2 expression in the inflamed mucosa of patients with IBD. Tissue samples were obtained endoscopically from patients with ulcerative colitis (UC) (n = 18), Crohn's disease (n = 10) and ischemic colitis (n = 8). Normal colorectal tissues were also obtained (n = 15). The caveolin expression was evaluated by standard immunohistochemical procedure. In normal colonic mucosa, caveolin-1 expression was detected in the smooth-muscle cells of the muscularis mucosae and the endothelial cells, but caveolin-2 expression was not detected. In the inflamed mucosa of patients with active UC, caveolin-2 expression was clearly detectable as small scattered foci on the luminal surfaces of epithelial cells, but caveolin-1 expression was similar to that in normal mucosa. Caveolin-2 expression increased in accordance with the disease activity of UC. This enhanced caveolin-2 expression was not detected in active Crohn's disease or ischemic colitis. In conclusion, we demonstrated that the epithelial expression of caveolin-2 is markedly enhanced in the inflamed mucosa of patients with UC. It is likely that the enhanced caveolin-2 expression in patients with UC was associated with the altered signal transductions in the intestinal epithelial cells. Furthermore, our results suggest that there are differences in the phenotypic features of epithelial cells between UC and Crohn's disease.

Caveolin 1↗
PubMed2001

Structural characterization of the O-antigenic polysaccharide chain of Porphyromonas circumdentaria NCTC 12469.

Structural studies were carried out on an O-antigenic polysaccharide moiety derived from Porphyromonas circumdentaria NCTC 12469, a reference strain of Porphyromonas species. The polysaccharide chain was composed of D-glucose, D-galactose, N-acetyl-D-glucosamine, and N-acetyl-D-galactosamine in a molar ratio of 1:2:1:1. On the basis of results from 1H- and 13C-NMR spectroscopic analyses including COSY, TOCSY, and HMQC experiments together with results of Smith degradation, methylation analysis, and partial acid hydrolysis, it is concluded that the polysaccharide chain has a pentasaccharide repeating unit of -->6)-beta-D-Glcp-(1-->6)-beta-D-Galp-(1-->3)-beta-D-GlcpNAc-(1-->3)-beta-D-GalpNAc-(1-->. The immunoreaction between P. circumdentaria LPS and the corresponding antiserum was strongly inhibited by the pentasaccharide fragment (Glc-Gal-Gal-GlcNAc-GalNAc) isolated from partial acid hydrolysis of the above polysaccharide, suggestive of O-antigen specific antibodies in the used antiserum.

Animals↗
PubMed2001

Germinated barley foodstuff exhibits different adsorption properties for hydrophilic versus hydrophobic bile acids.

BACKGROUND/AIMS: Germinated barley foodstuff (GBF), a type of dietary fiber, exhibits therapeutic effects in ulcerative colitis (UC) patients. However, the precise mechanisms responsible for these effects are still under investigation. On the other hand, it has been suggested that bile salts in the gut lumen play an important role in the integrity of the intestinal mucosa. The aim of the present study was to investigate the ability of GBF to adsorb bile salts in vitro. METHODS: The binding capacities of GBF, enzymatically digested GBF (GBF-fiber), and alpha-cellulose for unconjugated and conjugated bile salts were measured using Langmuir's method. The morphology of these fibers was observed by light and fluorescence microscopy. RESULTS: GBF adsorbed bile salts very strongly, especially hydrophobic bile salts. Even after enzymatic digestion, the GBF fiber still exhibited strong binding capacity, whereas alpha-cellulose exhibited very low binding capacity. Microscopically, GBF consists mainly of aleurone, a lattice-like cell wall with cytoplasm enclosed. After enzymatic digestion, the cytoplasm was also digested. CONCLUSION: GBF possesses a great capacity to adsorb bile salts. This may be part of the mechanism for the therapeutic effects of GBF in UC patients.

Adsorption↗
PubMed2001

Role of complement activation and mast cell degranulation in the pathogenesis of rapid intestinal ischemia/reperfusion injury in rats.

The aim of this study is to define the putative role of complement activation and mucosal mast cell (MMC) degranulation in the pathogenesis of rapid ischemia-reperfusion (I/R) injury. We prepared complement activity-depleted rats by the administration of the anti-complementary agent K-76COONa. To assess the role of MMC degranulation, we used the MMC stabilizer MAR-99 and genetically mast cell-deficient Ws/Ws rats. Autoperfused segments of the jejunum were exposed to 60 min of ischemia, followed by 60 min reperfusion. The epithelial permeability was assessed by (51)Cr-EDTA clearance rate, and the number of MMC was immunohistochemically assessed. I/R treatment induced a marked increase in mucosal permeability and MMC degranulation. The treatment with K-76COONa and MAR-99 significantly attenuated these changes. Furthermore, in Ws/Ws rats the increase in mucosal permeability and MMC degranulation was significantly attenuated. These findings indicate the role of complement activation and MMC activation in the pathogenesis of rapid intestinal I/R injury. A regulation of the complement activation and MMC degranulation may be one of the clinical strategies for prevention of I/R-induced mucosal injury.

Animals↗
PubMed2001

The clinical utility of contrast-enhanced 3D MR angiography for cerebrovascular disease.

The purpose of this study was to evaluate the usefulness of contrast-enhanced 3D MR angiography (CE-MRA) with an automated bolus-detection algorithm (SmartPrep technique) and the specialized phased-array coils for the patients suspected cerebrovascular disease. Forty-three patients with brain attack were examined with CE-MRA. A tracker volume of SmartPrep technique was placed along the ascending aorta in the coronal image. After the bolus injection of gadolinium, an increase in signal that corresponded to the arrival of gadolinium was used to trigger centric re-ordered spoiled gradient echo arterial selective MRA with imaging time of 20-40 sec. We were able to achieve a 100% successful triggering rate of SmartPrep technique and selectively arterial-phase carotid and vertebral arteries with almost no venous contamination could be delineated. These techniques enabled high resolution imaging of entire craniocervical arteries from aortic arch to the circle of Willis. This CE-MRA was useful to evaluate both occlusion of arteries and the collateral pathways and to measure stenosis and residual flow of dissection accurately. CE-MRA was a reliable less-invasive alternative to investigate the patients of cerebrovascular disease.

Brain↗
PubMed2001

Photoinduced electron transfer between chlorophylls (a/b) and fullerenes (C60/C70) studied by laser flash photolysis.

Photoinduced electron-transfer processes in the systems of chlorophylls (Chl) (chlorophyll-a [Chl-a] and chlorophyll-b) and fullerenes (C60/C70) in both polar and non-polar solvents have been investigated with nanosecond laser photolysis technique, observing the transient spectra in the visible/near-IR regions. By the excitation of Chl in benzonitrile (BN) it has been proved that electron transfer takes place from the triplet excited states of Chl to the ground states of C60/C70. By the excitation of C70 in BN electron transfer takes place from the ground states of Chl to the triplet excited state of C70. In both Chl the rate constants and quantum yields for the electron-transfer processes are as high as those of zinc porphyrins and zinc phthalocyanines, indicating that the long alkyl chains of Chl play no role in retarding the electron transfer. The rate constant for the electron-mediating process from the radical anion of C70 to octylviologen dication yielding the octylviologen radical cation was evaluated. The back electron-transfer process from the viologen radical cation to the radical cation of Chl-a takes place in a longer time-scale, indicating that a photosensitized electron-transfer/electron-mediating cycle is achieved.

Carbon↗
PubMed2001

Pseudoxanthoma elasticum diagnosed 25 years after the onset of cardiovascular disease.

A 63-year-old man who had experienced cerebral infarction and myocardial infarction at an early age, and repeatedly underwent coronary angioplasty was admitted to our hospital for cardiac evaluation. A coronary angiography showed complex multi-vessel disease with significant stenosis in all major vessels and coronary-artery bypass grafts. A funduscopic examination to evaluate hypertensive and diabetic changes revealed angioid streaks. Therefore, a skin biopsy was performed despite the absence of characteristic skin lesions. Histopathologic examinations revealed calcification and fragmentation of elastic fibers. Therefore, he was finally diagnosed as having pseudoxanthoma elasticum 25 years after the onset of cardiovascular disease.

Cerebral Infarction↗
PubMed2001

Circular stapling procedure for mucosal prolapse of the rectum associated with outlet obstruction.

The aim of this study was designed to investigate the outcome from using the new circular stapling device in the surgical treatment for mucosal prolapse of the rectum associated with outlet obstruction. The treatment consisted of resection of the mucosal prolapse through a transverse incision and resecting a suitable part of the mucosa between the rectum and the anal canal, using an HCS33 circular stapler. Eleven patients successfully underwent this operation without morbidity or mortality, and were assessed clinically and by rectoanal manometry and defecography pre- and post-operation. The mean operating time was 39 (range 22-49) min. The postoperative proctalgia and complications were mild, and the patients were discharged at 4 days after the operation. The pre-operative constipation was improved, and the patient's satisfaction was increased at one month after operation in comparison with the preoperative level. Rectoanal function test at 6 months after the operation demonstrated normalization of the maximum resting and squeezing pressures of the anal canal and rectal compliance to the normal levels. No patient has had recurrence of symptoms during the follow-up period. Our data suggest that this procedure may be a useful surgical treatment, as it causes little postoperative complication and enables early discharge of the patients. However, long-term outcomes of recurrence, continence, and constipation need to be evaluated in a more extended follow-up.

Female↗
PubMed2001

Total mesorectal excision, lateral lymphadenectomy and autonomic nerve preservation for lower rectal cancer: significance in the long-term follow-up study.

We clarify the significance of total mesorectal excision (TME), lateral lymphadenectomy (LLA), and of autonomic nerve preservation (ANP) compared to conventional surgery (CVS), for lower rectal cancer. All 458 patients curatively resected between 1962 and 1997 were retrospectively investigated. In Period I from 1962-1974, when CVS only was performed, in Period II from 1975-1984, TME or TME + LLA was performed, and in Period III from 1985-1997, TME + ANP, TME + ANP + LLA, or TME + LLA was performed. In Dukes A + B disease, there was no significant difference among the three periods, regardless of operation methods. In Dukes C disease, in Period I, CVS (42 patients: pts) had a local recurrence (LR) rate of 45.2% and 5-year disease-free survival (5YDFS) rate of 33.3%. In Period II, TME + LLA (82 pts) had a lower LR rate of 26.8% (p = 0.0628) and higher 5YDFS 51.0% (p < 0.05) vs CVS. In Period III, TME + ANP (12 pts) had LR 25.0% and 5YDFS 55.6%, TME + ANP + LLA (45 pts) had LR 13.3% (p < 0.005, vs CVS) and 5YDFS 56.1% (p < 0.01, vs CVS), and TME + LLA (18 pts) had LR 16.7% (p < 0.05, vs CVS) and 5YDFS 20.8%. Also, CVS had the lowest curability rate 64.8% and the highest mortality rate 7.2%. TME and/or LLA was significant for reducing LR and improving survival in patients with Dukes C lower rectal cancer, compared to CVS. ANP was beneficial with LLA. TME + ANP was suitable for Dukes A or B disease.

Autonomic Nervous System↗
PubMed2001

Laparoscopic ileus operation due to paracolostomy hernia.

We present a case report of a 62-year-old man with adhesive ileus caused by paracolostomy hernia. The patient underwent enterosynechotomy for ileus and colopexy for paracolostomy hernia laparoscopically. This procedure has benefits of prevention of recurrent adhesive ileus and early postoperative recovery of the intestinal tract.

Colostomy↗
PubMed2001

Dihydropyrimidine dehydrogenase activity and thymidylate synthase level are associated with response to 5-fluorouracil in human colorectal cancer.

In the recent studies associated with the modulation of 5-fluorouracil (5-FU) and the development of new antifolates, attentions have been focused on the expression of the target enzymes, thymidylate synthase (TS) and dihydropyrimidine dehydrogenase (DPD), that affect tumor sensitivity and resistance to drugs. In order to evaluate predictability of therapeutic efficacy by intratumoral enzyme activity, we investigated the role of TS content and DPD activity in tumor sensitivity of 5-FU. Surgical specimens were obtained from 51 patients with colorectal cancer and used to measure TS content and DPD activity. TS content and DPD activity in tissues were measured by [3H]-FdUMP binding assay and radioenzymatic assay, respectively. The sensitivity to 5-FU in tumor specimens was determined by collagen-gel droplet embedded-drug sensitivity test (CD-DST). The TS content and DPD activity did not correlate with Dukes' staging. There was no correlation between TS content and DPD activity in any tumors. Simple linear regression analysis showed that neither DPD activity (r = -0.267, p > 0.05) nor TS content (r = -0.277, p > 0.05) in tumors had a significant correlation with 5-FU effectiveness independently. Four out of 24 patients, highly responsive to 5-FU, showed low levels in both DPD and TS. The patients with high value in either DPD activity or TS content proved not to respond to 5-FU. In conclusion, these results demonstrate that both tumor DPD activity and TS content are the factors predicting 5-FU responsiveness in colorectal cancer.

Adult↗
PubMed2001

The usefulness of restorative laparoscopic-assisted total colectomy for ulcerative colitis.

The aim of this study was to evaluate the effectiveness of laparoscopic-assisted total colectomy with ileal J-pouch anal anastomosis in comparison with that of conventional open total colectomy in patients with ulcerative colitis. From 1990 until 1999, 11 patients underwent open total colectomy, while 21 patients had laparoscopic-assisted total colectomy. Patients characteristics, perioperative course, and recovery were compared. Differences between the groups were tested using Student's t-test for independent groups and chi-square tests when appropriate. Nasogastric tube could be removed after POD 1.1 vs. 4.8 (p < 0.05), the mean time to passage of stool was 1.7 (range, 1 to 3) vs. 5.4 (range, 3 to 7) days (p < 0.05), and in the laparoscopic group watery stool was soon made solid after POD 24.3 vs. 87.3 (p < 0.01). There were no significant differences in the mean operating time and mean estimated operating blood loss between two groups. Postoperative morbidity did not differ significantly between the patients treated conventionally (45.5%) and laparoscopically (33.3%). The findings of this study indicate that laparoscopic-assisted total colectomy improved cosmetic results and to be a safe and effective treatment for the elective surgery of ulcerative colitis.

Adult↗
PubMed2001

[A thyrotoxic myopathy accompanied with unusual muscle symptoms and MRI muscle findings].

We report a patient with thyrotoxic myopathy associated with unusual muscle symptoms. A 29-year-old man developed hyperhidrosis, diarrhea, increase in appetite, and excitability in July, 1999. In August, he experienced muscle stiffness in bilateral lower extremities after maintaining postures such as driving a car or sitting on a chair. He was admitted to our hospital, in January, 2000. On physical examination, goiter was noted. Neurological examination was normal except for proximal muscle weakness. Laboratory test showed elevated free T3 and free T4, decreased TSH. TSH receptor antibody was increased. MRI of lower extremities revealed atrophy of bilateral biceps femoris. Muscle strength increased gradually after an oral administration of thiamazole 30 mg/day, and muscle stiffness disappeared. The clinical features of this patient and differential diagnosis were discussed.

Adult↗
PubMed2001

Ambulatory monitoring of behavior in daily life by accelerometers set at both-near-sides of the joint.

In this paper we examined a new joint motion monitoring method by use of accelerometers to monitor subjects' detailed motion in daily activities. In this method two accelerometers are set at as near points of both sides around the joint as possible. The difference between these two sensors' outputs mainly depend on the joint angle because the centrifugal and the turning acceleration occurred by the rotation around the joint can be neglected. In the experiments we tried to monitor various subject's behaviors of his upper and lower extremities and whole body motion, and could show this method is useful for the ambulatory monitoring of behavior in daily life.

Acceleration↗
PubMed2001

[Cellular immunotherapy for local recurrence of rectal cancer after surgery by activated lymphocyte administration--a case report].

UNLABELLED: Intrapelvic recurrence of the rectal cancer after surgery is a challenging status. We report here a case of intrapelvic tumor due to the recurrence of rectal cancer postoperatively treated by adoptive cellular immunotherapy. CASE REPORT: A 57-year-old Japanese man with an intrapelvic tumor showing bone destruction due to the recurrence of rectal cancer after abdomino-peritoneal resection was diagnosed by CT scan. He consented to simultaneous adaptive cellular immunotherapy for local recurrent lesions by administration of the activated lymphocytes. The tumor sample used for the activation of PBMC was obtained by operation. Tumor cells were prepared by mincing and enzymatic digestion of the tumor sample, and they were irradiated with a dosage of 50 Gy. Peripheral blood samples were collected from the same patient. PBMC for about 2 weeks to prepare cells for treatment were obtained from the blood sample. One million PBMC were incubated in 2 ml of the culture medium containing 10(5) irradiated autologous tumor cells and 100 IU/ml recombinant IL-2. The activated PBMCs, as autologous cancer specific killer T cells, were administered by direct regional injection (from 2 million to 8 x 10(7) cells). These injections were given repeatedly about once a week at 2-week intervals for three months. The surface phenotypes of activated PBMC or PBMC were tested by two color immunostaining technique with anti-CD3, -CD4, -CD8 and also anti-CD16, -CD25 or -CD56. Natural killer cell activity was also investigated. The clinical outcome was evaluated by CT scan and serum CEA levels. In the cultured activated PBMCs, NK cell activity was 40%, both CD3 and CD4 positive cells was 30%, and both CD3 and CD8 positive cells was 48%. There were far more CD8 cells than CD4 cells. In the PBMC, NK cell activity had increased, both CD3 and CD4 positive cells had decreased and both CD3 and CD8 positive cells had increased. There were then predominantly more CD8 cells than CD4 cells by repeated administration of the cultured activated PBMCs. The only adverse effect was grade 2 fever. Serum CEA levels fell from 293.7 ng/ml to 160 ng/ml, but the tumor size on the CT scan was slightly increased except for the directly administered region. We have been observing him as an outpatient.

Humans↗
PubMed2001

Cloning and sequencing of two genes encoding chitinases A and B from Bacillus cereus CH.

Two genes encoding chitinases A and B (chiA and chiB) from Bacillus cereus CH were cloned into Escherichia coli XL1-Blue MRF', by using pBluescript II SK+, and their nucleotide sequences were determined. Open reading frames of the chiA and chiB genes encoded distinct polypeptide chains consisting of 360 and 674 amino acid residues, respectively, with calculated molecular sizes of 39,470 and 74,261 Da, respectively. Comparison of the deduced amino acid sequences with those of other bacterial chitinases revealed that chitinase A consisted of a catalytic domain, while chitinase B consisted of three functional domains, a catalytic domain, a fibronectin type III-like domain, and a cellulose-binding domain. The primary structures of these two proteins were not similar to each other.

Amino Acid Sequence↗
PubMed2001

[A case of lung metastasis from colon cancer treated successfully with combined chemotherapy of CPT-11 and 5'-DFUR].

The patient was a 52-year-old woman who had sigmoid colon cancer with liver metastasis and multiple lung metastases. Resection of curability B was performed, and alternating adjuvant chemotherapy consisting of hepatic artery injection of 5-FU and systemic administration of CPT-11 was performed. Lung recurrence was found and no antitumor effect of chemotherapy was observed, so the CPT-11 which had been administered every other week was given every week in a dose of 60 mg/body, half of the original dose. Moreover, 5'-DFUR was administered in a dose of 800 mg/day every day. As a result, lung metastasis tumors were reduced markedly. Adverse events such as nausea, vomiting and depilation were mitigated, and no other toxicity was observed. The patient could thus be treated extremely safely in the outpatient clinic. This was considered to be a valuable case suggestive of the significance of combination chemotherapy of CPT-11 and 5'-DFUR and the importance of appropriate administration of CPT-11.

Antineoplastic Combined Chemotherapy Protocols↗