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T Arai

Publications and source records attributed to T Arai.

At least 181 records · Page 10Linked to original sources
PubMed2000

Effect of canal drying methods on the apical seal.

The purpose of this study was to observe the seal obtained in human root canals under different in vitro treatment conditions. Root canals of freshly extracted human maxillary incisors received traditional biomechanical preparation and irrigation with 10% NaClO, followed by a final rinse of distilled water. Teeth were divided into four groups. In group 1, each root canal was dried with one paper point. In group 2, each root canal was dried with four paper points. Group 3 was dried with four paper points, followed by a gentle burst of warm air. Group 4 was dried using four paper points, followed by an internal 200 degrees C heat probe. Twenty canals in each group were filled with a gutta-percha cone and a zinc oxide-eugenol sealer, whereas 20 were filled with a glass ionomer sealer. All teeth were immediately immersed in India ink for 1 or 4 wk. The teeth were cleared, and the dye penetration-leakage measured with an accuracy of +/- 0.01 mm. Optimum sealing conditions were observed when the canal was dried with paper points and a 200 degrees C probe. There were no significant differences between 1 and 4 wk immersion. Glass ionomer sealer appeared more susceptible to the wet condition of the root canal walls than zinc oxide-eugenol sealer. An additional 40 teeth were prepared in the same manner as the dye penetration tests to observe the drying conditions of the root canal walls, and the moisture inside the canals was measured to an accuracy of 0.0001 g. The highest degree of internal canal wall dryness was found in group 4.

Air↗
PubMed2000

The walking bleach procedure: an in vitro study to measure microleakage of five temporary sealing agents.

The purpose of this study was to compare the in vitro sealing capacity of five materials, each used as a temporary sealing agent for the walking bleach technique. All teeth received traditional biomechanical root canal instrumentation, after which the walking bleach agent was placed in the pulp chamber space. The occlusal access was sealed with one of five temporary materials: two hydraulic filling materials, a photoactivated resin composite, a zinc oxide-eugenol cement, and a zinc oxide phosphate cement with/without the placement of a piece of rubber sheet that was placed as a barrier to isolate filling material from the bleaching agent. All teeth were stored in a 1% solution of Alcian blue with thermal cycling stress. After 1 wk, they were sectioned longitudinally, and ranked by graded scores of 0 to 3, according to the degree of the dye penetration. Significantly less dye microleakage was observed in the two hydraulic materials than in the photoactivated resin. Both zinc oxide-eugenol and zinc phosphate cements showed a considerable amount of microleakage. There were no significant differences between the groups with and without a rubber sheet. Our data demonstrate that hydraulic filling materials provide the most favorable cavosurface seal when they are firmly packed into the cavity space to prevent microleakage.

Alcian Blue↗
PubMed2000

Pathologic characteristics of colorectal cancer in the elderly: a retrospective study of 947 surgical cases.

To determine the pathologic characteristics of colorectal cancer in the very old, a retrospective study of 947 consecutive Japanese patients aged > or =65 with 1,039 lesions were examined. Pathologic findings in the very old group (>85 years, n = 140) were compared with those in the younger groups; young-old group (65-74 years, n = 352) and middle-old group (75-84 years, n = 455). Although male:female ratio significantly decreased with advancing age, reaching 1:1.8 in the very old group, the relative odds of colorectal cancer in men were higher than that in women in all age groups. In the very old group, cancer of the proximal colon (proximal to the splenic flexure) accounted for 52% in women and 37% in men, being significantly higher than those in the younger groups. Proximal colonic cancers increased with advancing age in both genders. Higher proportions of poorly differentiated adenocarcinoma, mucinous carcinoma, cancer >5 cm in size, and protruding type cancer were present in the very old group, although these kinds of tumors typically occur in the proximal colon. The incidence of multiple cancers in the large intestine was not different among any age group (average, 8.6%). These results indicated that, even in the very old, colorectal cancers showed marked proximal excess, being explained by effect of both age and gender, and that the proximal shift may influence the proportion of histologic type and size of the tumor. These findings have important implications for screening and diagnosis of colorectal cancer in the elderly.

Adenocarcinoma↗
PubMed2000

Various imaging modalities for the detection of salivary gland lesions: the advantages of 201Tl SPET.

The aim of this study was to compare dual-isotope (99Tc(m) and 201Tl) SPET imaging with computed tomography (CT) and magnetic resonance imaging (MRI) in the differentiation of various lesions of the major salivary glands. Twenty-two patients underwent dual-isotope SPET imaging, of whom 12 also had CT and 15 also had an MRI study. The uptake ratio and retention index for 99Tc(m) and 201Tl were calculated by drawing regions of interest on the involved and normal glands. Both CT and MRI were interpreted by two radiologists. All malignant tumours were detected by all three modalities. Warthin's tumours were detected by dual-isotope SPET imaging; however, MRI failed to differentiate Warthin's tumour from pleomorphic adenoma. Of 13 other benign tumours, dual-isotope SPET correctly diagnosed 12. Of 16 tumours showing a cold defect on the 99Tc(m) images, parametric analysis with 201Tl gave an accuracy of 94%, whereas CT gave an accuracy of 70-90%. MRI was 73-91% accurate in differentiating between benign (Warthin's) and malignant tumours. We believe that dual-isotope SPET imaging (99Tc(m) and 201Tl), together with semi-quantitative analysis, is the method of choice for differentiating between various lesions of the major salivary glands.

Adenolymphoma↗
PubMed2000

Introduction of the interleukin-10 gene into mice inhibited bleomycin-induced lung injury in vivo.

Interleukin (IL)-10 has been shown to reduce many inflammatory reactions. We investigated the in vivo effects of IL-10 on a bleomycin-induced lung injury model. Hemagglutinating virus of Japan (HVJ)-liposomes containing a human IL-10 expression vector (hIL10-HVJ) or a balanced salt solution as a control (Cont-HVJ) was intraperitoneally injected into mice on day -3. This was followed by intratracheal instillation of bleomycin (0.8 mg/kg) on day 0. Myeloperoxidase activity of bronchoalveolar lavage fluid and tumor necrosis factor-alpha mRNA expression in bronchoalveolar lavage fluid cells on day 7 and hydroxyproline content of the whole lung on day 21 were inhibited significantly by hIL10-HVJ treatment. However, Cont-HVJ treatment could not suppress any of these parameters. We also examined the in vitro effects of IL-10 on the human lung fibroblast cell line WI-38. IL-10 significantly reduced constitutive and transforming growth factor-beta-stimulated type I collagen mRNA expression. However, IL-10 did not affect the proliferation of WI-38 cells induced by platelet-derived growth factor. These data suggested that exogenous IL-10 may be useful in the treatment of pulmonary fibrosis.

Animals↗
PubMed2000

Increased LDL cholesterol and atherosclerosis in LDL receptor-deficient mice with attenuated expression of scavenger receptor B1.

Scavenger receptor BI (SR-BI) is a multiligand cell-surface receptor that plays a central role in high density lipoprotein homeostasis in rodents. To investigate a role for SR-BI in atherosclerosis, mice with attenuated SR-BI expression were crossed with low density lipoprotein (LDL) receptor-deficient mice. Compound-homozygous mutants showed increased plasma cholesterol, surprisingly due primarily to increased LDL cholesterol and apolipoprotein B levels. LDL turnover studies showed that this resulted from increased LDL cholesterol production rather than decreased LDL catabolism. Atherosclerotic lesion size was significantly increased in male compound-mutant mice relative to LDL receptor-deficient controls (93 427+/-16 079 versus 34 448+/-5 331 microm(2), respectively; P=0.003). The proatherogenic effect of attenuated SR-BI expression may in part be due to increased LDL cholesterol levels. These findings suggest that upregulation of the receptor could have therapeutic potential for the treatment of atherosclerosis.

Animals↗
PubMed2000

Induction of dog sperm capacitation by glycosaminoglycans and glycosaminoglycan amounts of oviductal and uterine fluids in bitches.

Ejaculated sperm collected from 12 beagle dogs were incubated in canine capacitation medium (CCM), supplemented with 5 microg/ml chondroitin sulfate A (CS), 5 microg/ml hyaluronic acid (HA), or 5 microg/ml heparin (HP) for 7 hr at 38 degrees C in a 5% CO2 in air atmosphere to investigate the effects of glycosaminoglycans (GAGs) on dog sperm capacitation. The percentages of motile sperm, hyperactivated sperm (%HY), and acrosome-reacted sperm (%AR) in all media were examined after 4 hr and 7 hr of incubation. The oviducts and uteri of 9 anestrous and 18 estrous beagle bitches were removed under halothane inhalation anesthesia to measure the total GAG amounts in oviductal and uterine fluids. The lumens of the ampulla of the oviducts, isthmus of the oviducts, and the uterine horns were each flushed with 1 ml HEPES-EDTA fluid. Total GAG amounts in the flush fluids obtained were measured with a spectrophotometer. Sperm motility (51-59%), %HY (79-86%), and %AR (31-36%) in CCM supplemented with CS, HA, or HP were significantly higher after 7 hr of incubation than when incubated in CCM without GAGs (P<0.01 or 0.05). The mean total GAG amounts in the fluids from the ampulla and isthmus of the oviducts and the uterine horns in the estrous bitches were higher than in the anestrous bitches. These results indicate that GAGs in the oviductal and uterine fluids in estrous bitches are associated with in vivo sperm capacitation.

Acrosome Reaction↗
PubMed2000

Measurement of anti-thyroglobulin and anti-thyroid peroxidase antibodies using highly sensitive radioimmunoassay: an effective method for detecting asymptomatic focal lymphocytic thyroiditis in the elderly.

Subclinical thyroiditis or thyroid dysfunction is relatively common in the elderly. To estimate the effectiveness of measurement of serum levels of anti-thyroglobulin and anti-microsomal or thyroid peroxidase antibodies for detecting focal lymphocytic thyroiditis (FLT) in the elderly, we examined the relationships between antibody titer and postmortem histological finding of the thyroid gland in 180 consecutive autopsies (69 women and 111 men) over 60 years of age without any overt clinical thyroid or collagen diseases. FLT was found in 25 cases (13.9%) with female predominance (21.7% in female vs. 9.0% in male). Measurements of serum levels of anti-thyroglobulin and anti-thyroid peroxidase antibodies by radioimmunoassay (TgAb and TPOAb, respectively) were compared with the measurements of anti-thyroglobulin and anti-microsomal antibodies by a hemagglutination technique (TGHA and MCHA, respectively), using sera from 25 patients with FLT and age- and sex-matched 51 patients without FLT. Among 25 cases with FLT, TgAb and TPOAb were positive in 17 (68%) and 12 (48%), respectively. There was a close relationship between degree of FLT and serum level of TgAb or TPOAb (P<0.0001). On the other hand, TGHA and MCHA were positive only in 8 (32%) and 10 (40%), respectively. TgAb and TPOAb were more sensitive than TGHA (68% vs. 32%, P<0.05) and MCHA (48% vs. 40%) to detect FLT. Positive findings in either TgAb or TPOAb significantly improved sensitivity (76%) compared with that of TGHA or MCHA (44%) (P<0.05). Specificities of combined measurements of TgAb and TPOAb (90%) were not significantly different from those of TGHA and MCHA (100%). These findings indicate that TgAb is a more sensitive method for detecting FLT and that its diagnostic sensitivity for FLT increases by using it in combination with TPOAb. Therefore, in the elderly without clinically or biochemically overt thyroid dysfunction, positive TgAb and/or TPOAb could imply presence of FLT, and their titers might reflect degree of inflammation.

Aged↗
PubMed2000

Technetium tin colloid test detecting symptomless dysphagia and ACE inhibitor prevented occurrence of aspiration pneumonia.

Symptomless dysphagia and swallowing disorders play a very important role in the pathogenesis of aspiration pneumonia. A videofluoroscopic examination and a simple two-step swallowing provocation test (STS-SPT) could be useful for detection of swallowing disorders in elderly patients with stroke, however, there is no report on such a test for detection of symptomless dysphagia. We administered 1 ml Technetium Tin Colloid (99mTC) to the patient during sleep via a nasal catheter placed in the mouth. At 09:00 h the next day, symptomless dysphagia was checked for by imaging. Improvement of the symptomless dysphagia was observed, and thus we could prevent the occurrence of aspiration pneumonia. The 99mTC test was particularly useful in detecting symptomless dysphagia in elderly patients with stroke.

Aged↗
PubMed2000

Effect of intrathecal nocistatin on the formalin-induced pain in mice versus that of nociceptin/orphanin FQ.

The effect of intrathecal nocistatin on formalin-induced pain in mice was investigated and compared with that of nociceptin/orphanin FQ (Noc/OFQ) to get information on the functional relationship between nocistatin and Noc/OFQ in the spinal cord. Subcutaneous injection of formalin into the hindpaw induced biphasic pain behaviors. Nocistatin, 1 pg, given intrathecally 1 min before 2% formalin injection, significantly attenuated the first phase of the formalin-induced pain. Also, 10 to 1000 pg of nocistatin, given 10 min after formalin injection, significantly inhibited the second phase of the formalin test. Naloxone, 5 mg/kg i.p., failed to antagonize inhibitory effects of nocistatin on either phase of the formalin-induced pain, indicating that analgesic effects of nocistatin were unrelated to the classic opioid system. At 1 to 100 pg, Noc/OFQ exerted no influence on either phase of the 2% formalin-induced pain. However, at 1% formalin, Noc/OFQ significantly aggravated the second phase at 10 pg but not the first phase at 1 to 1000 pg. This aggravating effect of Noc/OFQ was completely reversed by 10 pg of nocistatin. At 0.3 and 1 microg, Noc/OFQ, but not nocistatin, significantly inhibited both phases of the 2% formalin-induced pain. Suppressive effects of 1 microg of Noc/OFQ on the formalin-induced pain were not affected by 1 microg of nocistatin. These results suggest that Noc/OFQ might be involved in the second phase of the mouse formalin test and that, under such pathophysiological conditions, nocistatin could exhibit antagonism against Noc/OFQ at the spinal level.

Animals↗
PubMed2000

New multifunctional percutaneous transluminal coronary angioplasty catheter device capable of balloon inflation, local drug delivery and coronary perfusion.

A new percutaneous transluminal coronary angioplasty catheter with multiple functions of balloon inflation, local drug delivery and coronary perfusion has been devised. The device consists of an inflatable lumen, a drug delivery lumen, and a perfusion (or guide wire) lumen. A drug can be infused from the port located distal to the inflated balloon during continuous blood perfusion via the perfusion lumen. Fluorescence-labeled heparin and peroxidase administered using the device permeated into denuded vessel tissues during ongoing perfusion and remained there for over 24 hr. This prototype device indicates the potential therapeutic implications of the concepts of the device.

Angioplasty, Balloon, Coronary↗
PubMed2000

A new factor from Bacillus mesentericus which promotes the growth of Bifidobacterium.

It was reported previously that supernatants of cultures of Bacillus mesentericus TO-A promote the growth of Bifidobacterium species. In this study, a new growth-promoting factor, BM-1, was purified from the supernatant of such a culture and its chemical structure was determined. BM-1 was identified as 3,3-dihydroxyazetidine, and it promoted the growth of several strains of Bifidobacterium.

Azetidines↗
PubMed2000

Cytochrome P450 2E1 polymorphism in gastric cancer in Brazil: case-control studies of Japanese Brazilians and non-Japanese Brazilians.

Cytochrome P450 2E1 (Cyp2E1) is involved in the metabolic oxidation of carcinogenic nitroso compounds, including N-nitrosoamines. There is an RsaI polymorphism in the transcriptional regulatory region of this gene, and in vitro evidence suggests that the variant type of this polymorphic site has higher transcriptional activity but less chlorzoxazone-metabolizing activity. Interindividual differences in the metabolic capacity of Cyp2E1 are assumed to be associated with cancer susceptibility, but the results of the previous studies on the relation between Cyp2E1 RsaI polymorphism and cancer susceptibility have been inconsistent. Two case-control studies of gastric cancer in Japanese Brazilians (96 cases, 192 controls) and Brazilians not of Japanese ancestry (non-Japanese Brazilians; 236 cases, 236 controls) in São Paulo were designed to clarify the role of the Cyp2E1 RsaI genotype in susceptibility to gastric cancer after considering multifactorial environmental influences. The subjects with variant RsaI genotypes amounted to 47% (28 of 59) and 48% (64 of 133), respectively, of the Japanese cases and controls, and 6% (11 of 187) and 10% (19 of 192), respectively, of the non-Japanese cases and controls. As expected, a difference in the distributions of the two groups was observed. The odds ratio of the RsaI variant genotype of Cyp2E1 was 0.46 (95% confidence interval, 0.21-1.04) in the non-Japanese Brazilian population and 0.98 (95% confidence interval, 0.50-1.90) in the Japanese Brazilian population after adjusting for sex, age, tobacco use, and meat consumption. Additional adjustment for potential confounding factors did not change the odds ratio substantially. No significant interactions were observed between the polymorphism and environmental factors. In regard to the histological type of gastric cancer, the variant genotype was significantly more prevalent than the common genotype in Japanese subjects with diffuse type gastric cancer. Our study suggests that the Cyp2E1 RsaI polymorphism is associated with a reduced risk of gastric cancer, although how the assumed increase in Cyp2E1 expression produced by this polymorphism is related to a reduced risk of cancer remains unclear. The observations in this study are consistent with the recent observations of esophageal cancer in endemic areas of China.

Aged↗
PubMed2000

Immunohistochemical expression of glutathione transferase-pi in untreated primary non-small-cell lung cancer.

Patients with unresectable non-small-cell lung cancer (NSCLC) usually have undergone chemotherapy; however, such problems as resistance to chemotherapeutic agents occur during the treatments. Recent studies have indicated that glutathione S-transferase-pi (GST-pi) may play an important role in the resistance of cancer cells to alkylating agents, including cisplatin compounds. We examined a possible relationship between immunohistochemical expression of GST-pi and the response to cisplatin plus etoposide chemotherapy in patients with untreated and unresectable primary NSCLC. Of the 89 patients, 50 (56.2%) were GST-pi-positive and 39 (43.8%) were GST-pi-negative. For the patients with negative GST-pi expression, the response rate was 66.7% (26 of 39 patients). In the patients with positive GST-pi expression, the response rate was 26% (13 of 50 patients). This difference was statistically significant (P = .0019). The results suggest that GST-pi expression in NSCLC tissues is related to response to cisplatin plus etoposide chemotherapy and may be useful as a predictor of chemotherapy response.

Adenocarcinoma↗
PubMed2000

[Endonasal transsphenoidal surgery under local anesthesia for elderly patient with pituitary tumor: case report].

We present a surgical case under local anesthesia of an 88-year-old woman suffering from visual disturbance caused by pituitary adenoma. Magnetic resonance (MR) imaging showed a large pituitary tumor with suprasellar extension compressing the chiasmatic nerve. Neither she nor her family would agree to surgical therapy. However, when we proposed surgery under local anesthesia, they accepted it. Partial removal of the tumor via the endonasal transsphenoidal approach was carried out, uneventfully. The nasal surface was infiltrated with 4%-Xylocaine prior to the ordinary xylocaine injection to the nasal mucosa. The patient did not complain of any pain associated with the surgical procedure, including saline injection to the subarachnoid space through spinal drainage. The postoperative course was fine except for the temporarily appearance of diabetes insipidus. Postoperative MR imaging showed complete relief of compression to the chiasmatic nerve. Her visual field was improved dramatically. Endonasal transsphenoidal surgery under local anesthesia is thought to be one of the most useful methods of choice, especially in cases of elderly patient with pituitary tumor.

Adenoma↗