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T Tsuru

Publications and source records attributed to T Tsuru.

At least 73 records · Page 4Linked to original sources
PubMed1995

Measurement of tear electrolyte concentration and turnover rate using a flexible conductimetric sensor.

Tear fluid conductivity was measured by a non-invasive method. A flexible 3 mm-wide conductimetric sensor was placed inside the human subjects temporal lower cul-de-sac (similar to Schirmer test strip), and used to evaluate electrolyte concentration and turnover rate in tear for normal, healthy subjects aged between 30 to 85 years in a normal, light indoor environment. The tear electrolyte concentration was calculated from tear conductivity to give a mean value of 297 mEq/l (S.D. 30 mEq/l; n = 29) which was consistently with previously reported values. Tear turnover rate was calculated by a single exponential equation of tear conductivity change, following the application to the eye-drops of 40.0 milligrams sodium chloride solution. The mean turnover rate was 44.2% per minute (S.D. = 13.3% per minute; n = 30), being in agreement with previously reported values.

Adult↗
PubMed1994

[Quantitative analysis of glycosaminoglycans in tear fluids during corneal epithelial wound healing in rabbits].

We performed quantitative analyses of glycosaminoglycans in the tear fluids in a rabbit wound healing model. We ablated rabbit corneal epithelium with trephine and spatula, and sampled tear fluids before the epithelial ablation, and at 3, 24, 48, and 72 hours after it. After an instillation of 200 microliters saline solution in the conjunctival sac, as much tear fluid as possible was collected from the lower cul-del-sac. The glycosaminoglycans in the tears were then treated with chondoroitinase ABC to make fractions of disaccharides. The quantities of disaccharides were determined with high-performance liquid chromatography as weight per unit protein in the tears. The concentrations of delta Di-HA in the tear fluids at 3 and 24 hours were significantly higher than those before the treatment and returned to the initial value at 72 hours after making the epithelial wound. Among the disaccharides of chondroitin sulfate, delta Di-0S and delta Di-6S showed a significant increase at 3 hours after the treatment but delta Di-4S did not show any significant variation. The results suggest that the glycosaminoglycans in the rabbit tear fluids may play an important role in the corneal epithelial wound healing process.

Animals↗
PubMed1994

[Multivariate analysis of risk factors of rejection in penetrating keratoplasty].

In order to evaluate preoperative risk factors that affect the incidence of endothelial rejection after penetrating keratoplasty, we performed statistical analysis on 571 consecutive cases who had been followed at the University of Tokyo Hospital for at least one year. We applied a logistic regression model (multiple variate analysis) to determine the significance of the association between the preoperative factors and the incidence of rejection. We identified four preoperative risk factors of endothelial rejection in a year as follows: the extent of corneal vascularization, failed previous graft continuous sutures, and preoperative corneal endothelial damage. When the rejection cases were divided into an early group that suffered rejection within 3 months and a late group that suffered rejection after 6 to 12 months, young patients were likely to suffer rejection in the early postoperative period.

Adolescent↗
PubMed1994

[Histopathological study of the meibomian glands in 72 autopsy cases].

We investigated histopathological changes in human meibomian glands and analyzed the incidence of histopathological parameters and the relationship between parameters and age or sex of patients. Human meibomian glands, measuring 3 x 3 mm in size, were excised from both upper eyelids of 72 autopsy cases (mean age 63 +/- 12 years; 44 males, 28 females). The specimens were stained with hematoxylin and eosin and examined in detail with the light microscope. The following histopathological changes were investigated as parameters: (1) cystic dilatation of the duct and/or the acini, (2) atrophy of the acini, and (3) granulomatous inflammation. The incidences of the parameters were (1) 34.7% (25 cases), (2) 19.4% (14 cases), and (3) 18.6% (13 cases). There was statistically significant correlation between age and atrophy of the acini, which was found in the older patients. No sex difference was found in any of the parameters. These results suggest that the decrease in the meibomian gland secretion with aging is related to atrophy of the acini. These results further suggest that cystic dilatation, which has been described as a histopathological finding in meibomian gland dysfunction, may be caused by factors other than aging.

Adolescent↗
PubMed1994

[Statistic evaluation of prognostic risk factors in penetrating keratoplasty using Cox multiple regression model].

Preoperative risk factors that may influence the prognosis in penetrating keratoplasty were statistically analyzed on 698 consecutive eye that had been operated on at the University of Tokyo Hospital. A Cox multiple regression model (proportional hazards models) was constructed with simultaneous consideration of follow-up periods and prognostic factors. Six preoperative risk factors were identified: corneal endothelial damage, the presence of anterior synechiae, glaucoma, older donor age, the area of vascularization, and aphakia or pseudophakia. Simulations of the prognosis were attempted using the significant factors.

Adult↗
PubMed1993

Effect of T cells on the complement production by monocytes.

We studied the role of T cells in the regulation of C3 or C4 production by monocytes. While cocultured T cells reduced C3 production, they enhanced C4 production by monocytes in a number-dependent manner. Interleukin-2 enhanced these effects of T cells on C3 and C4 production, indicating that activated T cells had greater effects on complement production by monocytes. CD4+ T cells had greater effects than those of CD8+ T cells on the C3 or C4 production by monocytes, indicating that CD4+ T cells were mainly involved in the regulation of C3 and C4 production by monocytes. T-cell-conditioned medium (T-CM) also decreased C3 and enhanced C4 production, but the effect of T-CM on C3 and C4 production was less remarkable than that of T cells. T cells separated by transwell inserts from monocytes had similar effects as those of T-CM on complement production. Anti-IFN-gamma antibody completely blocked the suppressing effect on C3 production and partially blocked the stimulating effect of T cells on C4 production. These results indicate that T cells regulate C3 or C4 production by monocytes via IFN-gamma as a humoral factor. Moreover, the stimulating effect of T cells on C4 production was partially blocked when monocytes and T cells were incubated with anti-CD2, anti-LFA-1, and anti-HLA-DR antibodies, and anti-CD2 partially blocked the suppressing effect of T cells on C3 production by monocytes. These results indicate that T cells modulate the C3 and C4 production by monocytes not only via a humoral factor but also via a direct interaction with monocytes.

Cell Communication↗
PubMed1993

Primary collision neoplasm of malignant melanoma and adenocarcinoma in the lung. A case report.

We report an extremely rare case of a primary collision neoplasm in the lung consisting of malignant melanoma and adenocarcinoma. A malignant melanoma was histologically diagnosed by a transbronchial lung biopsy of the lung nodule in a 61-year-old woman, in whom there was no demonstrable primary malignant melanoma found elsewhere. However, at autopsy the above two components of the pulmonary tumor were both histologically and immunohistochemically confirmed. There was little intermingling of the two tumors. The malignant melanoma was positive for monoclonal antibody specific for melanotic tumor (HMB45) and S-100 protein but was negative for epithelial membrane antigen (EMA), while it was the opposite in the adenocarcinoma. This case is, to our knowledge, the first reported collision tumor of the above two components.

Adenocarcinoma↗
PubMed1993

Annular pancreas associated with pancreaticobiliary maljunction in an infant.

We report the first known case of an annular pancreas associated with pancreaticobiliary maljunction without cholangiectasis in an infant, aged 2 years and 5 months in Japan. Only two other cases have been reported in Japan both of which were in adults. In our case, the main clinical features were abdominal pain, vomiting and an increasing level of plasma amylase. Endoscopic retrograde cholangiopancreatography (ERCP) was not successful in demonstrating the pancreaticobiliary maljunction due to duodenal stenosis. At operation, a complete type of annular pancreas was found with no enlargement of the common bile duct. We could visualize the pancreaticobiliary maljunction using cholangiopancreatography from the gallbladder during the operation. We then performed duodeno-duodenostomy (side-to-side anastomosis, diamond anastomosis) and portal jejunostomy (Roux en Y anastomosis). The infant was discharged in a good condition at 13 days after the operation. The pattern of the pancreatic ducts was Millbourn's 2a and the type of the duct in the annular portion was Yumura's type I. These results correspond to Lecco's hypothesis that the ring formation originates from the ventral pancreas. It has been further suggested that the cacogenesis and/or dysplasia of the ventral pancreas plays a role in the development at the stage of the pancreaticobiliary maljunction.

Abnormalities, Multiple↗
PubMed1993

Torsion of the gallbladder in a thirteen year old boy--case report.

Torsion of the gallbladder in a child is rare and only 23 cases in children have been reported in Japan. A preoperative diagnosis is very difficult and only four cases have been diagnosed, preoperatively, to date. In the case reported here the suspected preoperative diagnosis was an acute cholecystitis. During the operation, the gallbladder was found to be enlarged to twice the normal size and twisted 540 degrees in a clockwise direction around the cystic duct. A cholecystectomy with abdominal drainage was successfully performed; and the patient was discharged in good condition, 13 days after the operation. It was concluded that one of the most important features for the preoperative diagnosis of torsion of the gallbladder is a dislocation on ultrasonography.

Adolescent↗
PubMed1993

Increased incidence of cholestasis during total parenteral nutrition in children--factors affecting stone formation.

Cholelithiasis is extremely unusual in infants and children. Recently, some cases of cholelithiasis associated with total parenteral nutrition (TPN) have been reported. A group of 400 children receiving TPN were evaluated prospectively for the presence of gallstones and sludge in this report. Eight children (2%) were determined by ultrasonography to have developed cholelithiasis. All of these patients had received large amounts of amino acids (> or = 1.8g/kg/day) and relatively low amounts of fat (< or = 1.7g/kg/day) with a high ratio of non-protein: kcal/ml (> 0.8). It was concluded that the administration of large amounts of amino acids and a high ratio of non-protein: kcal/ml enhanced the risk for formation of gallstones and sludge. Conversely, these are prevented by the administration of appropriate amounts of fat.

Adolescent↗
PubMed1993

Clinical application of new membrane filter for cytopathological diagnosis in ophthalmology.

In order to evaluate the clinical usefulness of a new membrane filter method, PORETEC, for cytopathological diagnosis in ophthalmology, we performed a comparative study on conjunctival cell specimens using this method and a previously developed cytocentrifugation method. The subjects were 5 normal male volunteers (6 eyes) with an average age of 33 years. The conjunctival cells were obtained by brush cytology, and processed for both the new membrane filter and the cytocentrifugation methods. The total numbers of epithelial cells obtained by both methods were counted under a light microscope. The number of cells obtained by the cytocentrifugation method was 4933 +/- 2338 for each specimen, whereas that by the new membrane filter method was 12436 +/- 5281 (mean +/- SD). The difference was statistically significant (Wilcoxon signed-rank test, P < 0.05). The new membrane filter diagnostic method was also applied to specimens of aqueous humor from patients with uveitis or vitreous body from patients with proliferative diabetic retinopathy or endophthalmitis. The new method provided excellent cytopathological specimens which were also applicable for special staining and immunocytochemical study. We concluded that the new membrane filter is quite useful for cytopathological diagnosis of ocular fluid specimens.

Adult↗
PubMed1992

[Effects of argon laser irradiation of the iris on the concentration of aqueous prostaglandins and cyclic AMP].

In order to elucidate the influence of acute ocular inflammation on the aqueous humor dynamics and intraocular pressure (IOP), we carried out argon laser photo-coagulations on the rabbit irises and determined the concentrations of aqueous humor prostaglandins (PGs), cyclic AMP and protein. The IOP changed in a biphasic manner, i.e. initial hypertension and later hypotension. The concentrations of aqueous humor PG E2, PG F2 alpha and protein increased markedly after laser irradiation and then decreased gradually, although the concentrations of PG E2 and protein remained significantly higher than the baseline values at 24 hours after the irradiations. The concentrations of aqueous cyclic AMP of the irradiated eyes and control eyes were 67.8 pmol/ml and 29.3 pmol/ml, respectively. We presumed that the increase in concentration of aqueous cyclic AMP and breakdown of the blood-aqueous barrier by PGs caused the reactive hypotension.

Animals↗
PubMed1992

Effects of cell differentiation on the synthesis of the third and fourth component of complement (C3, C4) by the human monocytic cell line U937.

Association of complement synthesis with cell differentiation in U937 cells was investigated using granulocyte-macrophage colony-stimulating factor (GM-CSF), vitamin D3 and interferon-gamma (IFN-gamma) as differentiation-inducing agents. GM-CSF or vitamin D3 enhanced the synthesis of the third component of complement (C3) by U937 cells, but had no stimulatory effect on the synthesis of the fourth component of complement (C4). IFN-gamma increased both C3 and C4 synthesis by U937 cells. Combination of two of these three agents resulted in synergistic enhancement and all three agents caused maximal enhancement of C3 synthesis. Vitamin D3 enhanced IFN-gamma-induced C4 synthesis by U937 cells. These results were confirmed by ELISA and SDS-PAGE after biosynthetic labelling. GM-CSF, vitamin D3 or IFN-gamma increased the expression of complement receptor type 3 (CR3), one of the markers of monocyte/macrophage differentiation. Two of these agents caused a further increase and all three agents maximal increase in CR3 expression. Since C3 was synthesized in parallel with the degree of CR3 expression, the synthesis of C3, but not C4, by U937 cells is thought to be closely related to cell differentiation. It was reconfirmed that the synthesis of C3 and C4 by U937 cells was independently regulated.

Cell Differentiation↗
PubMed1988

New quantitative method to determine protein concentration and cell number in aqueous in vivo.

We have developed a new quantitative method to determine protein concentration and number of cells in the aqueous in vivo. The principal instruments in the system were a He-Ne laser and a detection system for measuring scattered light intensity. The power of the He-Ne laser was 25 microW and the focused beam diameter was 20 microns. The laser beam was operated by an optical scanner. The sampling window, 0.3 X 0.5 mm, was fixed in the center of the laser path. For the protein concentration measurement, the laser beam was scanned for a length of 0.6 mm vertically, covering the sampling window. To minimize signal contamination by background laser scattering, scattered light intensity produced by aqueous protein (Sp) was calculated as follows. Sp = Si - (S'o + S''o)/2, where Si indicates scattered light intensity when the beam passed in the sampling window and S'o and S''o indicate scattered light intensity when the beam passed above and below the sampling window. For the cell counts, the laser beam (0.25 X 0.6 mm) was scanned over the sampling window and the detected peaks were counted. Each measurement mode took 0.5 seconds. The operation of the instrument and data analysis were performed by a personal computer. In in vitro measurements with human plasma solution in diluting factors ranging from 1/50 to 1/10(4), and bovine serum albumin solution in concentrations ranging from 1 g/100 ml to 1 mg/100 ml, significant linear correlations between the values for concentration and photon counts (/msec) were obtained in each solution (r, ranging from 0.987 to 0.998, P = 0.000). In in vitro experiments with latex particles with diameters of 2.02 or 2.95 microns, significant correlations between the number of detected peaks and latex particles were also obtained. However, as the number of latex particles decreased, the variation in the number of detected peaks was large. In 31 normal young adults, with an average age of 23 years, the average photon count was 4.1 +/- 1.0, which corresponded to 27 mg/100 ml according to the in vitro bovine albumin solution measurement, and there was no definite relation in photon counts between eyes with and without mydriatics. Twenty patients with incipient or immature cataract, whose ages averager 70 years, showed significantly higher average photon counts, 6.2 +/-2.5, than the above young adults.We concluded that this new method of determining protein concentration and cell number in the aqueous enabled us to make a noninvasive and quantitative evaluation of the inflammation in the anterior segment of the eye.(ABSTRACT TRUNCATED AT 400 WORDS)

Aged↗