Search PubMed⌕ Search

Biomedical subjects

T Matsuo

Publications and source records attributed to T Matsuo.

At least 361 records · Page 20Linked to original sources
PubMed1995

Immunoglobulins in periapical exudates of infected root canals: correlations with the clinical findings of the involved teeth.

This study quantified the concentrations of IgG and IgA in the periapical exudates obtained from 69 single-rooted teeth using enzyme-linked immunosorbent assays, and examined their correlation with clinical findings of the involved teeth. Changes in the levels of these immunoglobulins during root canal treatment were also investigated. The average levels of IgG (85.61 mg/ml) was significantly higher than that of IgA (0.65 mg/ml) (P < 0.001). The exudates from the canals with large lesions (> or = 1 cm in diameter on radiographs) showed significantly higher IgG and IgA levels than small lesions (< 1 cm in diameter) (P < 0.01). The tendency for these to be a decrease in the levels of IgG and IgA was observed following the root canal treatment. These observations suggest that IgG and IgA are involved in the immunopathogenesis of periapical lesions.

Bacterial Infections↗
PubMed1995

Inflammation after cataract extraction and intraocular lens implantation in patients with rheumatoid arthritis.

AIMS: The purpose of this study was to examine whether preoperative activity of rheumatoid arthritis influences the extent of anterior chamber inflammation after cataract extraction and intraocular lens implantation. METHODS: The medical records of 23 consecutive patients (33 eyes) with rheumatoid arthritis, who underwent cataract extraction with intraocular lens implantation, were reviewed during a 4 year period from April 1990 to March 1994. RESULTS: Eleven patients who still showed a 1+ level of aqueous cells 1 month after the surgery had significantly higher titres of rheumatoid factor preoperatively, compared with the other 12 patients who showed no aqueous cells (p = 0.0019, Mann-Whitney U test). The persistence of aqueous cells also had a significant correlation with extracapsular cataract extraction compared with phacoemulsification (p = 0.0391, chi 2 test). Multivariate analysis showed that the titre of rheumatoid factor was the more significant element to determine the persistent aqueous inflammation. All the eyes, except for four which had a macular hole, optic disc atrophy, or retinitis pigmentosa gained visual acuity of 20/30 or better. The aqueous cells cleared 3 months after the surgery and left no complications in any of the eyes. CONCLUSION: Intraocular lens implantation is basically a safe procedure for patients with rheumatoid arthritis, although postoperative aqueous inflammation tends to be persistent in patients with high titres of rheumatoid factor.

Aged↗
PubMed1995

Endogenous Aspergillus endophthalmitis associated with periodontitis.

We report a 64-year-old woman who developed endogenous endophthalmitis in the course of severe periodontitis. Histopathological examination of the vitreous debris obtained during vitrectomy disclosed fungi and its culture identified Aspergillus flavus. Periodontitis should be considered as one of the infectious foci for endogenous fungal endophthalmitis as well as bacterial endophthalmitis.

Aspergillosis↗
PubMed1995

Suppression of plasma-activated factor VII levels by warfarin therapy.

To investigate the effect of warfarin treatment on the early phase of tissue factor-induced coagulation, we measured plasma-activated factor VII (factor VIIa) levels by a direct fluorogenic assay in 74 cardiovascular disease patients on long-term oral anticoagulation. We divided the patients into three groups based on the international normalized ratio (INR). In the patients with INR ranges of < 1.7 and 1.7 to 2.5, factor VIIa levels were 42% and 61% lower, respectively, than in age- and sex-matched controls. Factor VII coagulant activity (factor VIIc), factor VII antigen (factor VIIag), protein C, and factor X levels were also reduced to a similar extent in both groups. However, in patients with an INR > 2.5, the factor VIIa level was not decreased compared with that at an INR of 1.7 to 2.5, although the factor VIIc, factor VIIag, factor X, and protein C levels were all decreased further. Although the precise relation between the reduction of factor VIIa levels and the increase of INR requires appropriately designed long-term clinical trials, our data suggest that an INR range of 1.7 to 2.5 is sufficient for the suppression of factor VIIa. During the long-term follow-up of three patients with congenital antithrombin III or protein C deficiency, the factor VIIa level was more responsive to changes in the warfarin dose than the INR, and there were generally no corresponding changes of the thrombin-antithrombin III complex (TAT) level. However, one patient showed a transient marked increase of factor VIIa during the discontinuation of warfarin that was accompanied by an increase in TAT. Based on these findings, factor VIIa could be useful for monitoring both hypercoagulable and hypocoagulable states.

Adult↗
PubMed1995

Activation of tissue factor-induced coagulation and endothelial cell dysfunction in non-insulin-dependent diabetic patients with microalbuminuria.

We studied the relationships between albuminuria, tissue factor-induced coagulation, and endothelial cell dysfunction in 67 patients with non-insulin-dependent diabetes mellitus (NIDDM) who were divided into three groups on the basis of their urinary albumin excretion rate (AER). To assess the early phase of tissue factor-induced coagulation, activated factor VII (FVIIa) levels in plasma were measured by a direct fluorogenic assay. As markers of endothelial cell dysfunction, levels of von Willebrand factor (vWF), tissue-type plasminogen activator-plasminogen activator inhibitor-1 (TPA-PAI-1) complex, PAI-1, and tissue factor pathway inhibitor (TFPI) were measured. FVIIa levels were increased in normoalbuminuric NIDDM patients (AER < 15 micrograms/min) when compared with normal control subjects. This FVIIa increase was accompanied by an increase in thrombin-antithrombin III complex (TAT) levels, indicating increased activation of coagulation even in normoalbuminuric patients. In NIDDM patients with microalbuminuria (AER = 15-200 micrograms/min), the FVIIa level, the FVIIa-FVII antigen (Ag) ratio (an indicator of activation of FVII zymogen to FVIIa), and the TAT level were further increased. This group also had higher levels of endothelial cell-derived factors (vWF, TPA-PAI-1 complex, and PAI-1) than the control group. The levels of endothelial cell-derived factors (including TFPI) were highest in the NIDDM patients with overt albuminuria (AER > 200 micrograms/min). In all 67 diabetic patients, AER showed a strong positive correlation with FVIIa (r = .574, P < .0001) and a weakly but still significant correlation with FVIIa-FVII:Ag (r = .365, P = .01), vWF (r = .315, P < .01), and TAT (r = .323, P < .01).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Effect of Guglielmi detachable coils on experimental carotid artery aneurysms in primates.

BACKGROUND AND PURPOSE: Clinical experience has established that intravascularly placed metal coils can be a useful treatment for cerebral vascular aneurysms. However, the mechanism by which the coils induce occlusion of the aneurysm is unclear. Appropriate use of this promising treatment modality requires basic understanding of the occlusive process. We used an animal model system of experimentally induced carotid aneurysms to investigate the initial events induced by Guglielmi detachable coils (GDCs), as well as the subsequent vascular changes induced by the coils over time. METHODS: We induced 23 aneurysms in the carotid arteries of 16 Japanese monkeys. Nineteen aneurysms were then occluded with GDCs placed via endovascular surgery; 4 aneurysms served as controls. We then used gross and microscopic pathological examination, angiography, and scanning electron microscopy to assess the effects of the GDC. RESULTS: In the first few hours after placement of the GDC in the experimental aneurysms, we observed leukocyte attachment and deposition of fibrinlike materials and other proteins. By 4 days after coil placement, leukocytes and fibroblasts were observed in the thrombus. By 2 weeks after coil placement, there was evidence of an endothelial-like covering of the coils. At 3 months after coil placement, we observed development of an arterial media in the occluded aneurysms. CONCLUSIONS: The GDCs initiated a cellular response within several hours of aneurysm occlusion. By 2 weeks after coil placement, endothelialization was proceeding, and by 3 months after occlusion, remodeling of the aneurysm had progressed to produce a media-like structure in the former aneurysm.

Aneurysm↗
PubMed1995

Anti-Human T-lymphotropic virus type-I antibodies in atomic-bomb survivors.

Adult T-cell leukemia (ATL), induced by human T- lymphotropic virus type-I (HTLV-I), is endemic in Nagasaki, Japan. To investigate the effects of atomic-bomb radiation on development of this specific type of leukemia, 6182 individuals in the Radiation Effects Research Foundation (RERF) Adult Health Study sample in Hiroshima and Nagasaki were examined for positive rate of HTLV-I antibody. Several lymphocyte parameters were also studied for 70 antibody- positive subjects in Nagasaki. The HTLV-I antibody-positive rate was higher in Nagasaki (6.36%) than in Hiroshima (0.79%) and significantly increased with increasing age, but no association was observed with radiation dose. Whether relationship existed between antibody titer levels and radiation dose among antibody-positive subjects was not The frequency of abnormal lymphocytes tended to be higher in antibody-positive subjects than in antibody-negative subjects, and higher in females than in males regardless of radiation dose. The lymphocyte count was lower in antibody-positive subjects than in antibody-negative subjects and lower in female than in male subjects. No evidence was found to suggest that atomic-bomb radiation plays an important role in HTLV-I infection.

Adult↗
PubMed1995

Effects of the neonatal vitamin A exposure on behaviors of adult rats.

The effects of neonatal vitamin A exposure on six behavioral parameters in adult Wistar rats were investigated. Newborn male rats were injected intraperitoneally with 80,000 IU/kg/day of retinol palmitate (vitamin A) dissolved in physiological saline or vehicle alone (controls) during 1-5 days after birth. The animals were examined using the open field test (at 36 weeks of age), the rotarod test (38 weeks), the Biel water-maze test (40 weeks), the conditioned avoidance test (42 weeks), the running-wheel activity with pentobarbital challenge test (44 weeks), and the tail flick test (45 weeks). The vitamin A-exposed rats made significantly more errors and took significantly longer times in the Biel water-maze test, and showed significantly slower responses in the tail flick test than the controls. No significant effects of treatment with vitamin A were observed in any of the other behavioral tests. These results indicate that a long-lasting defect in learning in water-maze task and depression of the heat-pain response are induced in rats exposed neonatally to vitamin A.

Animals↗
PubMed1995

Effects of chemical sympathectomy on lipoprotein lipase activities in peripheral tissues of rats fed high fat diets consisting of different fats.

We have previously reported that the feeding of a beef tallow diet gives lower lipoprotein lipase activities in the interscapuler brown adipose tissue, heart and soleus muscle compared with feeding of a safflower oil diet. We have also suggested that sympathetic activities (norepinephrine turnover rates and beta-adrenergic receptor bindings) in these peripheral tissues were lower in the beef tallow diet group. To confirm the effects of dietary fats on the lipoprotein lipase activities in these tissues related to sympathetic activities, rats were chemically sympathectomized by treatment with 6-hydroxydopamine. The sympathectomized rats and control rats were meal-fed with a beef tallow diet or a safflower oil diet for 8 weeks. Sympathectomy abolished the differences in lipoprotein lipase activities in the interscapuler brown adipose tissue, heart and soleus muscle between two dietary groups. The percentage of body fat was increased by sympathectomy, resulting in no difference between the beef tallow diet group and the safflower oil diet group. These results suggest that intake of the beef tallow diet decreased lipoprotein lipase activities by reducing the sympathetic activities.

Adipose Tissue, Brown↗
PubMed1995

Marked increase of activated factor VII in uremic patients.

We investigated plasma activated factor VII (FVIIa) levels in uremic patients (nondialysis group: n = 38; dialysis group: n = 36) and healthy controls (n = 32). We also measured the plasma levels of thrombomodulin (an indicator of endothelial cell injury) and tissue factor. Plasma FVIIa showed a marked increase in the nondialysis group (mean [95% confidence interval]: 4.6 [4.1-5.1] ng/ml, p < 0.0001) with the progressive impairment of renal function, as indicated by the serum creatinine level, when compared with the 32 controls (2.8 [2.5-3.1] ng/ml), and was further increased in the dialysis group (6.1 [5.5-6.8] ng/ml, p < 0.001 vs. nondialysis group). Plasma levels of thrombomodulin and tissue factor were also higher in the nondialysis group than the control group, and were further increased in the dialysis group. Plasma tissue factor levels did not show any correlation with FVIIa or thrombomodulin in both the nondialysis and dialysis groups. Thus, circulating tissue factor appears to be released by a different mechanism from thrombomodulin and may not contribute to the direct activation of factor VII in uremic patients. On the other hand, the plasma level of thrombomodulin was positively correlated with that of FVIIa in the nondialysis group, and this correlation was independent of renal function. Thus, enhanced conversion of factor VII zymogen to FVIIa, probably related to endothelial cell injury, may be a risk factor for cardiovascular events in uremic patients.

Aged↗
PubMed1995

Genetic determinants of plasma factor VII activity in the Japanese.

We investigated the frequency of the factor VII Gln353 (FVII Gln353) allele in Japan, where coronary artery disease is much less common and factor VII coagulant activity (FVIIc) is lower than in Western countries. Japanese males (n = 144) aged 40-59 years living in 2 different districts were studied, and the FVIIc and activated factor VII (FVIIa) levels were measured with human (FVIIa Hum) and bovine soluble tissue factor (FVIIa Bov). The frequency of the FVII Gln353 allele in the 2 districts was 0.026 and 0.052 (combined: 0.034), which was about one third of that in a European population. Thus, the lower FVIIc level in Japanese is not due to the effect of FVII Gln353 allele. Ten individuals with the Gln353 allele showed a 39% decrease of FVIIa Hum levels and a 29% decrease of the FVIIa Bov level compared with 134 individuals homozygous for the FVII Arg353 allele. These decreases of FVIIa were greater than the decrease of FVIIc (17%), suggesting that FVII Gln353 may be difficult to activate in vivo. The marked decrease of FVIIa levels in individuals with the FVII Gln353 allele suggests that they are genetically protected against cardiovascular disease irrespective of ethnic background, by virtue of their decreased FVIIa level.

Adult↗
PubMed1995

Changes in beta 1- and beta 2-adrenoceptor mRNA levels in alveolar type II cells during cultivation.

Alveolar type II cells, the progenitor of type I epithelial cells, synthesize and secrete pulmonary surfactant. In this study, we determined the levels of mRNA for beta 1- and beta 2-adrenoceptor in cultured type II cells using a quantitative RNase protection assay. The mRNA levels for beta 1- and beta 2-adrenoceptors in the freshly isolated cells were 0.51 +/- 0.07 and 1.92 +/- 0.19 amol/microgram total cellular RNA, respectively. In the cells cultured for over 2 days, only beta 1-adrenoceptor mRNA level was remarkably reduced. These results suggest that each mRNA expression may be separately regulated in cultured alveolar type II cells.

Animals↗
PubMed1995

Time-lapse microcinematography of osteocytes.

We succeeded in the isolation of osteocytes from parietal bones of 16-day-old chick embryos. Isolated osteocytes showed a typical stellate morphology. More than 95% of these cells reacted with the osteocyte-specific antibody OB 7.3. In culture osteocytes formed gap junctions with each other, as could be established by ACAS. Sixteen-millimeter time-lapse microcinematography of the cells also demonstrated the formation of intercellular connections and gap junctions, and portrayed the interaction between osteocytes and osteoclasts: osteocytes seemed to inhibit osteoclast activity. This cinematography also showed the ability of osteocytes to proliferate after they had been disconnected from each other. Thereafter these cells redifferentiated into osteoblasts that became embedded in bone matrix produced by themselves. These findings suggest that osteocytes might be involved in bone formation during remodeling.

Animals↗
PubMed1995

Effect of the angiotensinogen gene Met235-->Thr variant on blood pressure and other cardiovascular risk factors in two Japanese populations.

OBJECTIVE: To investigate the gene frequency of the T235 allele and its relationship with hypertension in two Japanese populations. METHODS: T235 was investigated by restriction fragment length polymorphism using the polymerase chain reaction technique in 213 Japanese males aged 40-59 years, who were randomly selected from participants in the Jichi Medical School Cohort Study (Awaji-Hokudan population, n = 157; Niigata-Yamato population, n = 56). RESULTS: The gene frequency of the T235 allele in the two populations was very similar (Awaji-Hokudan 0.65, Niigata-Yamato 0.62; mean 0.64). The T235 frequency was 0.60 in normotensive males, approximately 1.2- to 1.7-fold that in Caucasians. Hypertension, in particular that associated with a positive family history of hypertension, was more common in individuals homozygous for the T235 allele. The levels of total cholesterol, blood glucose and fibrinogen showed a weak and non-significant relationship with the angiotensinogen genotype. CONCLUSION: The T235 angiotensinogen allele was more common in Japanese than in Caucasians, and was a predisposing factor for hypertension.

Adult↗
PubMed1995

[Stereotactic radiation therapy with linear accelerator: accuracy of alignment and portal film verification].

Stereotactic radiation therapy with a linear accelerator requires precise alignment of therapeutic radiation distribution to the target volume. To verify the accuracy of alignment, differences between the stereotactic coordinates of the center of the therapeutic radiation distribution determined from portal films and those of the target points determined from CT/MRI or CT/angiographic localization were calculated for 58 points. The average values and one standard deviation were--0.02 +/- 0.50mm, 0.37 +/- 0.39mm and 0.01 +/- 0.25mm in the x, y, and z directions, respectively. The average value of the total deviation was 0.73 +/- 0.07mm. Potential sources of misalignment were misaligned laser pointers, wide laser beam width, improperly zeroed target positioner scale, and motion of the patient couch. The accuracy of alignment should be verified prior to irradiation. Portal film verification is indispensable for strereotactic radiation therapy with a linear accelerator.

Cranial Irradiation↗
PubMed1995

The strong positive correlation between factor VII clotting activity using bovine thromboplastin and the activated factor VII level.

We compared factor VII clotting activity (FVIIc) assays using different thromboplastins to determine which is the most sensitive for activated FVII (FVIIa) or for FVII antigen (FVIIag). FVIIc levels were measured using thromboplastins derived from bovine brain (FVIIc Bov), human placenta (FVIIc Hum), and rabbit brain (FVIIc Rab). FVIIa levels were measured by fluorogenic assays using human soluble tissue factor (rsTF) or bovine rsTF. We also measured FVII activity by an amidolytic assay (FVIIc:am Hum) using human thromboplastin and a chromogenic substrate for thrombin. FVIIag levels were determined by ELISA. In the FVIIa assay, the reaction time obtained from using bovine rsTF was shorter than that with human rsTF, suggesting that the interaction of plasma FVIIa with bovine rsTF was stronger than with human rsTF. The plasma FVIIa levels measured using human rsTF and bovine rsTF were almost the same (r = 0.947, p < 0.0001). Among the three FVIIc assays, FVIIc Bov had the strongest positive correlation with the plasma FVIIa level (r = 0.886, p < 0.0001), but had no correlation with FVIIag. An increase of 1 ng/ml in the plasma FVIIa level yielded a 27.9% increase of FVIIc Bov. Plasma FVIIc Hum and FVIIc:am Hum showed moderate correlations with both FVIIa (r = 0.520, p < 0.02 and r = 0.569, p < 0.01, respectively) and FVIIag (r = 0.438, p < 0.05 and r = 0.468, p < 0.05, respectively). FVIIc Rab had the lowest correlation with FVIIa (r = 0.367, p < 0.1), but had a moderate correlation with FVIIag (r = 0.436, p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

High lipoprotein (a) levels in chronic hemodialysis patients are closely related to the acute phase reaction.

To study the mechanism underlying the high lipoprotein (a) [Lp(a)] level in uremic patients on chronic hemodialysis, we investigated the levels of Lp(a), acute phase reactants (C-reactive protein and sialic acid), and interleukin-6 (IL-6) in 54 dialysis patients. The mean [95% CI] Lp(a) level was increased in the hemodialysis patients compared with the 30 controls (30 [25-36] vs. 18 [14-23] mg/dl, p < 0.005). Among dialysis patients, 46% had an Lp(a) level > 30 mg/dl, which was significantly higher than the percentage in the control group (17%). The levels of C-reactive protein, sialic acid, and IL-6 were also increased in dialysis subjects compared with controls (200 [134-299] vs. 37 [24-58] micrograms/dl, p < 0.0001; 63 [59-66] vs. 54 [52-56] mg/dl, p < 0.002; and 9.2 [7.8-11] vs. 5.5 [5.0-6.1] pg/ml, p < 0.0005, respectively). The Lp(a) level was positively correlated with that of C-reactive protein (r = 0.415, p < 0.002), sialic acid (r = 0.426, p < 0.002), and IL-6 (r = 0.298, p < 0.05) in the hemodialysis patients, but not in the controls or non-dialysis uremic patients. The Lp(a) level in the dialysis patients was also positively correlated with activation markers of coagulation (thrombin-antithrombin III complex and plasmin-alpha 2-plasmin inhibitor complex, p < 0.005). These results indicate that the Lp(a) level is closely related to the acute phase reaction and hypercoagulability in chronic hemodialysis patients.

Acute-Phase Reaction↗