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T Muto

Publications and source records attributed to T Muto.

At least 37 records · Page 2Linked to original sources
PubMed2002

The effect of head posture on the pharyngeal airway space (PAS).

The purpose of this study was to investigate the relationship between cranio-cervical inclination and pharyngeal airway space (PAS) by measuring these parameters at different head postures in the same subjects and to obtain a regression equation to correct the values measured. Fifty lateral cephalometric radiographs taken at five different head postures per individual were obtained from ten adults (seven males and three females) aged from 25 to 30 years with nose breathers and Class I occlusion. The changes in cranio-cervical inclination produced by head extension were correlated with changes in the variables describing the PAS. The OPT/NSL (cranio-cervical inclination in the second vertebrae) and C3-Me (distance between the third vertebrae and the Menton) correlated strongly with PAS-TP (the most proximal distance measured between the posterior pharyngeal wall and the tongue base) in the pharyngeal airway space (r = 0.807 and 0.854 respectively). The regression equations were Y = - 27.177+0.39X (Y = PAS-TP, X = OPT/NSL), and Y = -21.105+0.402X (Y = PAS-TP, X = C3-Me), respectively. From these equations we could conclude that an increase of 10 degrees in OPT/NSL or 10 mm in C3-Me increased the pharyngeal airway space (PAS-TP) by about 4 mm.

Adult↗
PubMed2001

Elongation of the pi-system of phthalocyanines by introduction of thienyl substituents at the peripheral beta positions. Synthesis and characterization.

1,4,8,11,15,18,22,25-octabutoxyphthalocyanines ((OBu)8Pcs) having eight 2-thienyl (1) and [2,2'-bithiophene]-5-yl (2) groups at beta positions and their zinc(II) and cobalt(II) derivatives were prepared from 2-thienyl- (3) or [2,2'-bithiophene]-5-yl (4)-substituted phthalonitriles in moderate to good yields. The electronic absorption spectra of the Pcs showed red-shifted Q-bands relative to beta-unsubstituted (OBu)8Pcs. The longer substituent, the [2,2'-bithiophene]-5-yl group, is more effective than the 2-thienyl group in enlarging the pi-conjugated system of the Pcs. The ring oxidation potential obtained by cyclic voltammetry shifted cathodically with increasing chain length, indicating destabilization of the HOMOs. Due to the shift of the Q-band, 2-thienyl- and [2,2'-bithiophene]-5-yl-substituted Pcs exhibit a remarkable color change from the original green color.

Journal Article↗
PubMed2001

Cloning and characterization of FGF23 as a causative factor of tumor-induced osteomalacia.

Tumor-induced osteomalacia (TIO) is one of the paraneoplastic diseases characterized by hypophosphatemia caused by renal phosphate wasting. Because removal of responsible tumors normalizes phosphate metabolism, an unidentified humoral phosphaturic factor is believed to be responsible for this syndrome. To identify the causative factor of TIO, we obtained cDNA clones that were abundantly expressed only in a tumor causing TIO and constructed tumor-specific cDNA contigs. Based on the sequence of one major contig, we cloned 2,270-bp cDNA, which turned out to encode fibroblast growth factor 23 (FGF23). Administration of recombinant FGF23 decreased serum phosphate in mice within 12 h. When Chinese hamster ovary cells stably expressing FGF23 were s.c. implanted into nude mice, hypophosphatemia with increased renal phosphate clearance was observed. In addition, a high level of serum alkaline phosphatase, low 1,25-dihydroxyvitamin D, deformity of bone, and impairment of body weight gain became evident. Histological examination showed marked increase of osteoid and widening of growth plate. Thus, continuous production of FGF23 reproduced clinical, biochemical, and histological features of TIO in vivo. Analyses for recombinant FGF23 products produced by Chinese hamster ovary cells indicated proteolytic cleavage of FGF23 at the RXXR motif. Recent genetic study indicates that missense mutations in this RXXR motif of FGF23 are responsible for autosomal dominant hypophosphatemic rickets, another hypophosphatemic disease with similar features to TIO. We conclude that overproduction of FGF23 causes TIO, whereas mutations in the FGF23 gene result in autosomal dominant hypophosphatemic rickets possibly by preventing proteolytic cleavage and enhancing biological activity of FGF23.

Alanine↗
PubMed2001

NMR identification of the Tom20 binding segment in mitochondrial presequences.

Many mitochondrial proteins are synthesized in the cytosol as precursors with N-terminal presequences, and are imported into mitochondria with the aid of translocator protein complexes containing presequence-binding proteins. Tom20, a receptor protein which functions in an early step of the mitochondrial protein import, recognizes presequences with divergent amino acid sequences. Here, we report the identification of the segments involved in binding to Tom20 in mitochondrial presequences. We monitored the chemical shift perturbation of the NMR signals of five different 15N-labeled presequence peptides by the addition of the cytosolic receptor domain of rat or yeast Tom20. The perturbed segments occupy different positions, either near the N terminus or at the C terminus, in the presequences. Spin label experiments revealed that this is not due to different orientations of the presequence peptides bound to Tom20. The results presented here will offer a starting point to perform detailed analyses of Tom20-binding elements by systematic amino acid replacements.

Amino Acid Sequence↗
PubMed2001

Safety and efficacy of granulocyte and monocyte adsorption apheresis in patients with active ulcerative colitis: a multicenter study.

Active ulcerative colitis (UC) is characterized by activation and infiltration of granulocytes and monocytes/macrophages into the colonic mucosa. The infiltrated leukocytes can cause mucosal damage by releasing degradative proteases, reactive oxygen derivatives, and proinflammatory cytokines. The aim of this trial (conducted in 14 specialist centers) was to assess safety and efficacy of granulocyte and monocyte adsorption apheresis in patients with active UC most of whom were refractory to conventional drug therapy. We used a new adsorptive type extracorporeal column (G-1 Adacolumn) filled with cellulose acetate beads (carriers) of 2 mm in diameter, which selectively adsorb granulocytes and monocytes/macrophages. Patients (n = 53) received five apheresis sessions, each of 60 minutes duration, flow rate 30 ml per minute for 5 consecutive weeks in combination with 24.4 +/- 3.60 mg prednisolone (mean +/- SE per patient per day, baseline dose). During 60 minutes apheresis, 26% of granulocytes, 19.5% of monocytes and 2% of lymphocytes adsorbed to the carriers. At week 7, 58.5% of patients had remission or improved, the dose of prednisolone was reduced to 14.2 +/- 2.25 mg (n = 37). The apheresis treatment was fairly safe, only eight non-severe side effects (in 5 patients) were reported. Based on our results, we believe that in patients with active severe UC, patients who are refractory to conventional drugs, granulocyte and monocyte adsorption apheresis is a useful adjunct to conventional therapy. This procedure should have the potential to allow tapering the dose of corticosteroids, shorten the time to remission and delay relapse.

Adult↗
PubMed2001

Evaluation of a multicomponent workplace health promotion program conducted in Japan for improving employees' cardiovascular disease risk factors.

BACKGROUND: The long-term effectiveness of multicomponent worksite health promotion programs targeting cardiovascular disease risk factors remains unclear in Japan. This study was conducted to evaluate the effectiveness of such a health promotion program consisting of a main program provided over 4 days and a follow-up program provided over 1 year. METHODS: The subjects of this randomized controlled trial were male employees working for a building maintenance company in Japan. The intervention group (n = 152) and the control group (n = 150) consisted of employees having abnormal findings in at least one of the following items at baseline health examination: body mass index (BMI), systolic (SBP) or diastolic blood pressure, total cholesterol, HDL cholesterol, triglycerides, and fasting blood glucose. Evaluation was conducted at 18 months after the main program. RESULTS: BMI, SBP, total cholesterol, and triglycerides improved significantly in the intervention group compared with the control group (P < 0.05). When comparisons were limited to those who showed abnormality at baseline, BMI, total cholesterol, and triglycerides improved significantly in the intervention group (P < 0.05). CONCLUSIONS: The multicomponent health promotion program provided to employees was shown to be effective in improving obesity, high blood pressure, and hyperlipidemia when evaluated 18 months after the main intervention program.

Adult↗
PubMed2001

Thoracic empyema associated with recurrent colon cancer: report of a case and review of the literature.

Many types of infections associated with colorectal cancer have been reported. Here, we describe a rare case of thoracic empyema that was observed during immunotherapy for recurrent colon cancer. Culture of the pleural fluid yielded Streptococcus bovis, which is known to be associated with gastrointestinal lesions, especially colorectal malignancies. The possible correlation between these two clinical entities-empyema and colon cancer-is discussed.

Adenocarcinoma↗
PubMed2001

Randomized, controlled trial of lateral node dissection vs. nerve-preserving resection in patients with rectal cancer after preoperative radiotherapy.

PURPOSE: The effectiveness of preoperative radiation therapy for advanced lower rectal carcinoma to preserve the function of pelvic organs and reduce local recurrences was examined in a prospective, randomized, controlled study. METHODS: Fifty-one patients with a diagnosis of localized and resectable adenocarcinoma of the lower rectum undergoing 50 Gy of preoperative radiotherapy were recruited into the trial between April 1993 and March 1995. The patients were randomly allocated to complete autonomic nerve-preserving surgery without lateral node dissection (D1), or surgery with dissection of the lateral lymph nodes including autonomic nerves (D2) followed by oral administration of carmofur for one year. RESULTS: No difference was observed in either survival or disease-free survival between D1 and D2 groups. There was no difference between the two groups in terms of recurrence rate. A significant difference was observed in urinary and sexual function (P = 0.02 and 0.02, respectively) one year after surgery between D1 and D2 groups. CONCLUSION: This study suggests that lateral node dissection is not necessary in terms of curability for patients with advanced carcinoma of the lower rectum who undergo preoperative radiotherapy.

Adenocarcinoma↗
PubMed2001

Colorectal cancer statistics in Japan: data from JSCCR registration, 1974-1993.

Japanese colorectal cancer statistics from 1974 to 1993 are reported, based on the accumulated data registered by the member institutions of the Japan Society for Cancer of the Colon and Rectum (JSCCR). Both colon and rectal cancers were more prevalent in men than in women. In both sexes, colonic cancers were more prevalent than rectal cancers, and a greater increasing trend was seen in colonic cancers. Moderately differentiated adenocarcinoma seemed to have increased in recent years. The resectability and operative death rates improved slightly, but the ratio of stage I + II/III + IV cancers (both colonic and rectal) did not change at all during the 20-year period reported. The yearly improved survival in both colonic and rectal cancers, particularly in stages II and III, may well reflect improved surgical techniques.

Adenocarcinoma↗
PubMed2001

Neck muscle responses to abrupt vertical acceleration in the seated human.

The control of neck muscle during marked changes in "g" loading must be to protect head-trunk orientation. However, little is known about the organization of reflexes. We therefore investigated the shortest latency in neck muscle evoked by abrupt ascending and descending vertical acceleration with a stroke of 20 cm and peak acceleration 0.4xg in six healthy subjects. The subjects were seated upright and restrained on a chair driven by a hydraulic servo system. Ascent induced small responses in sternocleidomastoid muscles (SCMs) with a latency of 24.0 ms (SE 1.7) from onset of head acceleration, followed by larger responses of 100 ms in duration. In comparison the responses in SCMs evoked by descent were significantly delayed, with greater interindividual variations at 44.1 ms (SE 3.1) and smaller in amplitude than responses in ascent. Latencies were consistent and showed no habituation. In order to eliminate stretch components, we measured the neck responses to vertical acceleration with the head fixed by cervical collar. The latency of the fast response of SCM evoked by ascent was not significantly different from the latency of SCMs without the collar. These results may indicate that the fast responses of SCMs to sudden ascent may be composed of a vestibular-collic reflex for making the neck and head rigid for defense to sudden gravitational change.

Acceleration↗
PubMed2001

Role of esophagectomy in treatment of esophageal carcinoma with clinical evidence of adjacent organ invasion.

With carcinoma of the thoracic esophagus, clinical evidence of invasion of adjacent organs (T4) indicates a highly advanced stage, and most surgeons avoid esophagectomy. Although the therapeutic strategy for such disease is generally selected based on preoperative evaluation and intraoperative inspection, their accuracy and the relation to survival outcomes after esophagectomy have seldom been analyzed on the basis of exact histopathologic evidence. We performed esophagectomy, with perioperative adjuvant therapy when possible, on patients with clinical-T4 tumors unless absolutely unresectable conditions were detected. Among the 500 patients who underwent esophagectomy, the 78 patients whose tumors were confirmed to be T4 pathologically were compared with patients whose tumors were assessed as T4 preoperatively or intraoperatively to evaluate the role of esophagectomy for clinical-T4 carcinoma. Esophagectomy was possible for 99% of the pathologic-T4 tumors preoperatively assessed as resectable, but the resection was grossly incomplete in 35%. The true-positive rates in tumors preoperatively and intraoperatively assessed as T4 were 51% and 84%, respectively. The hospital mortality rate in patients with pathologic-T4 tumors was 4%. The overall 5-year survival rate for patients with pathologic-T4 tumors was 14%, compared with 60% for those with tumors assessed as T4 intraoperatively but not pathologically. Esophagectomy with perioperative adjuvant therapy yielded occasional cure with an acceptable mortality rate for patients with pathologic-T4 tumors assessed as technically resectable. Preoperative assessment and intraoperative macroscopic inspection had limitations for predicting pathologic-T4 disease and incomplete resection. Only patients with definitive evidence of unresectability should be excluded from esophagectomy.

Carcinoma, Squamous Cell↗
PubMed2001

Superficial depressed early carcinoma that developed into protuberant advanced carcinoma in the transverse colon.

A screening colonoscopic examination in a 70-year-old man revealed a nonpolypoid type superficial depressed early carcinoma, about 2cm in diameter, in the transverse colon. The lesion was not resected and was observed because of coexisting nonresectable hepatocellular carcinoma (HCC). Fifteen months later, follow-up examinations revealed a polypoid type protuberant advanced carcinoma, about 6 cm in diameter, at the same site. Because complete response of the HCC had been induced by transarterial embolization, the colon carcinoma was operatively resected. There is an indefinite concept that colorectal carcinomas develop without substantial morphological changes, and no superficial depressed carcinoma that developed into a protuberant type advanced carcinoma has been reported. The case reported here provides evidence that some polypoid carcinomas arise from superficial depressed precursors. There is some intermingling between the two postulated colorectal carcinogenic pathways, the conventional polypoid pathway named the "adenoma-carcinoma sequence", and the nonpolypoid pathway, including so-called "de-novo" carcinogenesis.

Aged↗
PubMed2001

Infected abdominal aortic aneurysm presenting with sudden appearance: diagnostic importance of serial computed tomography.

The case of an 86-year-old man with an infected abdominal aortic aneurysm (AAA) that developed suddenly over 3 weeks is presented here. Previous reports on the diagnosis of infected AAA have focused mainly on the findings of single computed tomography (CT). These include the presence of a saccular aneurysm with an irregular lumen, perianeurysmal fluid, gas and/or hematoma, osteomyelitis in adjacent vertebral bodies, disruption of intimal calcification, and obscuring of the aortic wall. Our case report presents a useful diagnostic technique for the diagnosis of infected AAA, emphasizing the importance of serial CT for suspected cases, even if the initial scan does not demonstrate the findings listed above.

Aged↗
PubMed2001

Associations of distinct variants of the intestinal mucin gene MUC3A with ulcerative colitis and Crohn's disease.

Ulcerative colitis (UC) and Crohn's disease (CD), the major forms of inflammatory bowel diseases (IBDs). are multifactorial disorders of unknown etiology. We reported a possible association of rare variable number of tandem repeat (VNTR) alleles of the "MUC3" gene with a susceptibility to UC. However, an entire structure of "MUC3" is still unknown because the long stretches of tandem repeats in this "gene" make its cloning extraordinarily difficult. In this study, we report evidence that "MUC3" consists of two genes, MUC3A and MUC3B, both of which encode membrane-bound mucins with two epidermal growth factor-like motifs, and we describe the complete 3'-terminal structures of these two genes. We have also analyzed the single nucleotide polymorphisms (SNPs) in the exonic sequences of the 3' portions of these two genes to investigate whether sequence variations in these regions can cause person-to-person differences in the susceptibility to IBDs, and report here that non-synonymous SNPs of MUC3A, involving a tyrosine residue with a proposed role in cell signaling, may confer genetic predisposition to CD (P = 0.0132). Our findings suggest that variants of MUC3A may be involved in the occurrence of UC and CD in distinct manners.

Amino Acid Sequence↗
PubMed2001

The indication of local excision for T2 rectal carcinomas.

BACKGROUND: Several researchers reported that local excision with or without postoperative chemo-radiation therapy is an alternative approach for sphincter preservation in patients with locally invasive rectal carcinoma. However, indications and long-term results have not yet been determined. METHODS: Seventy-two patients with T2 colorectal carcinomas underwent bowel resection with regional lymph node dissection. The associations between lymph node metastasis (LNM) and clinicopathologic factors were examined with special reference to the presence or absence of moderate to severe degree of focal dedifferentiation or mucinous component at the invasive margin (unfavorable histology). RESULTS: Multivariate logistic regression analysis revealed that both sex and unfavorable histology were significantly associated with LNM (P = 0.0102, 0.0226, respectively). However, the associations between LNM and lymphatic invasion or tumor location were not statistically significant (P = 0.0947, 0.1738). CONCLUSIONS: When locally resected T2 rectal carcinoma specimens have unfavorable histology at the invasive margin, additional bowel resection with lymph node dissection should be recommended.

Colorectal Neoplasms↗
PubMed2001

Anatomical major resection versus nonanatomical limited resection for liver metastases from colorectal carcinoma.

BACKGROUND: Although systematic anatomical hepatic resection has been reported to improve patient survival in hepatocellular carcinoma, principles of hepatectomy procedure have not been clearly demonstrated in secondary hepatic malignancy. The purpose of the present study was to determine whether selection of surgical procedures for liver resection is associated with the pattern of tumor recurrence or patient survival. METHODS: During the period of 1980 through 1999, 174 cases underwent liver resection for hepatic metastasis from colorectal cancer. Of these, 96 underwent systematic anatomical major hepatic resection (anatomical group) and 78 cases underwent nonanatomical limited resection (nonanatomical group). Subset analysis of 115 patients with unilobar single or double tumors was also conducted. RESULTS: The overall 5-year survival rate of 174 patients was 43.2%. Univariate analysis did not show a significant difference in patient survival according to surgical procedure (anatomical group versus nonanatomical group). Operative morbidity and mortality rates were slightly higher in anatomical group. From the subset analysis in unilobar single or double tumors, anatomical major hepatectomy was unnecessary in 80.4% of the cases if the tumors were resectable by nonanatomical limited resection. Ninety percent of the ipsilateral recurrence, which could have been avoided if the first operation was anatomical hemihepatectomy, could undergo second hepatectomy with 5-year survival rate of 58.3%. CONCLUSIONS: There was not a significant difference in patient survival according to surgical procedure. To minimize surgical stress and operative risk, nonanatomical limited liver resection should be a basic surgical procedure for colorectal metastases.

Colorectal Neoplasms↗
PubMed2001

Proliferative activity of intrahepatic colorectal metastases after preoperative hemihepatic portal vein embolization.

Although hemihepatic portal vein embolization (PVE) has been used preoperatively to extend indications for hepatectomy in patients with colorectal metastases, the effects of this procedure on tumor growth and outcome remain controversial. To address this issue, we assessed the proliferative activity of intrahepatic metastases after PVE and the long-term outcome of this procedure. Eighteen patients with colorectal metastases underwent preoperative PVE between 1996 and 2000 (PVE group). Twenty-nine patients who underwent major hepatic resection without PVE served as control (non-PVE group). The hepatic parenchymal fraction of the left lobe had significantly increased from 38.1 +/- 3.2% to 45.9 +/- 2.9% 3 weeks after PVE (+20.5%, P <.0001). Tumor volume and percent tumor volume had also significantly increased from 223 +/- 89 mL to 270 +/- 97 mL (+20.8%, P =.016) and from 13.7 + 4.3% to 16.2 + 4.9% (+18.5%, P =.014), respectively. There was no apparent correlation between the increase in parenchymal volume and that in tumor volume. The Ki-67 labeling index of metastatic lesions was 46.6 +/- 7.2% in the PVE group and 35.4 +/- 12.6% in the non-PVE group (P =.013). Long-term survival was similar in the PVE and non-PVE groups, however, disease-free survival was significantly poorer in the PVE group than in the non-PVE group (P =.004). We conclude that PVE increases tumor growth and probably is associated with enhanced recurrence of disease. Although PVE is effective in extending indications for surgery, patient selection for PVE should be cautious.

Adult↗