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Biomedical subjects

T Sumii

Publications and source records attributed to T Sumii.

At least 37 records · Page 2Linked to original sources
PubMed1995

Pancreatic enlargement in obstructive jaundice. Effects of biliary stream diversion in humans.

To verify the influence of obstructive jaundice on pancreatic growth, the anteroposterior width of the pancreas was measured by computed tomography in 30 cholangiocarcinoma patients excluded patients with distal bile duct tumor (jaundice group) and 74 control subjects. Follow-up examinations were performed on 12 patients with and without internal biliary drainage to elucidate the temporal relationship between pancreatic enlargement and the diversion of the obstructed biliary stream. Histologic analysis on autopsy samples from 13 control and 10 jaundice cases also was performed. Mean pancreatic head and body widths in the jaundice group were 2.93 +/- 0.3 cm and 2.01 +/- 0.3 cm, respectively. These values were significantly greater than those of the controls (2.13 +/- 0.3 cm and 1.49 +/- 0.3 cm, P < 0.01). The glandular widths returned to their normal sizes following internal biliary drainage. No changes were seen in patients who underwent external drainage alone. Histologic examination revealed that enlargement of the acinar cells or of the islet of Langerhans was often seen in the jaundiced patients. Therefore obstructive jaundice is thought to cause pancreatic growth through a trophic effect by interrupting biliary circulation.

Aged↗
PubMed1995

[Chronic pancreatitis and pancreatic dysfunction associated with Sjögren's syndrome].

Some pancreatic involvement was observed in Sjögren's syndrome (SS). Episodes of abdominal pain occurred infrequently in the course of SS, but there were some abnormal findings of the pancreatic functions and/or morphologic examinations. The level of serum amylase was affected by the destruction of both the pancreas and the salivary gland. Hyposecretion of bicarbonate in secretin test seemed to be characteristic in SS. ERP showed mild or moderate changes of the pancreatic duct, but their severities did not correlate with those of the salivary gland. Imaging of the pancreas tended to reveal definite abnormalities only in cases with an attack of pancreatitis. The roles of autoimmune mechanisms have been reported in pancreatitis associated with SS.

Amylases↗
PubMed1995

Evaluation of dimensional stability of elastomeric impression materials during disinfection.

Disinfection of impression materials is recommended for preventing cross-contamination in dental clinics. However, aspects of the evaluation of elastomeric impression materials only slightly subjected to the effects of disinfectants have not been established. Therefore, the effects of sodium hypochlorite, glutaral, iodine, and ethanol disinfectants on elastomeric impression materials, condensation silicone, polysulfide, addition-type silicone (vinyl silicone), hydrophilic vinyl silicone, and polyether, were evaluated directly in a time-dependent manner by a non-contact displacement meter. Condensation silicone impression materials and polysulfide rubber impression materials greatly shrank over time, but their shrinkage decreased with immersion in disinfectants. Vinyl silicone impression materials and polyether impression materials showed excellent dimensional stability in air. However, hydrophilic vinyl silicone impression materials and polyether impression materials expanded greatly when immersed in disinfectants, especially when immersed in ethanol. Hydrophobic vinyl silicone impression materials showed excellent dimensional stability regardless of the presence or absence of disinfectants.

Dental Impression Materials↗
PubMed1995

Study of a Pd-Ag-Sb system alloy for metal-ceramics.

The present study is aimed at developing a palladium silver based alloy containing antimony and other elements for metal-ceramics. Composition 54.2Pd-36.2Ag-4.7Sb-2.9In-1.0Sn-1.0Ga++ + (alloy No. 10) was finally selected as the best for practical applications. Liquidus and solidus temperatures of this alloy were 1,250 degrees C and 1,087 degrees C. Under fired conditions, the Vickers hardness number, tensile strength, and elongation were 270, 647 MPa, and 3.4%, respectively. In the temperature range from 20 degrees C to 600 degrees C, the thermal expansion rate was 0.87%, and the thermal expansion coefficient was 15.0 X 10(-6)/degrees C. The mechanical and manipulation properties of this alloy were satisfactory for clinical applications.

Antimony↗
PubMed1993

Role of local pancreatic blood flow in development of hemorrhagic pancreatitis induced by stress in rats.

Our previous data showed that the pancreatitis induced in rats by cerulein develops into hemorrhagic pancreatitis following water-immersion stress. The present study examined the effects of water-immersion stress and high doses of cerulein (intraperitoneal injection) on pancreatic blood flow. Five hours of water-immersion stress reduced the local pancreatic blood flow to approximately 30% of the initial value (253.75 +/- 12.58 ml/min/100 g) without causing any histological alterations. Blood flow was decreased as early as 1 h after the immersion and reached the lowest value (30% of initial value) 3 h after the immersion. The administration of 40 micrograms/kg body wt cerulein as two intraperitoneal injections reduced the pancreatic blood flow by 40% 5 h after the first cerulein injection. The injections of cerulein combined with water-immersion stress did not reduce the pancreatic blood flow more than did water-immersion stress alone. The systemic blood pressure was unaffected during 5 h of water immersion after the cerulein injections. These findings suggest that in rats the stress-induced decrease of local pancreatic blood flow may not produce pancreatitis, but may aggravate an existing acute pancreatitis.

Amylases↗
PubMed1993

Acute pancreatitis induced by cyclosporin A under stimulation of pancreas by caerulein.

Our purpose was to investigate enzymatically and morphologically the acute effect of the immunosuppressive agent cyclosporin A (CsA) on the exocrine pancreas of rats. The intravenous injection of CsA 10 and 20 mg/kg body weight (BW) increased the content of pancreatic amylase and protein and decreased the content of pancreatic DNA. Histologically, we observed intraacinar vacuolization and individual cell necrosis. Under stimulation of the pancreas by two intraperitoneal injections of caerulein 5 micrograms/kg BW at 1-h intervals (which did not induce any evident change in the pancreas), CsA induced a significant increase in serum amylase and in pancreatic wet weight in a dose-dependent manner. CsA at doses of 10 and 20 mg/kg BW produced a significant increase in the content of pancreatic amylase and protein. Macroscopically, we observed marked pancreatic edema, venous dilatation, and patchy hemorrhage. Histologically, there were significant differences in the severity of intra-acinar vacuolization, interstitial edema, neutrophil infiltration, individual cell necrosis, and hemorrhage, severity of which was dose dependent. Pancreatic ductal erosion was particularly marked following treatment with CsA 20 mg/kg BW. These findings indicate that CsA accelerates abnormal pancreatic enzyme secretion and suggest that the therapeutically recommended doses of CsA can induce acute pancreatitis under stimulation of the pancreas.

Acute Disease↗
PubMed1992

Horseshoe anomaly of the pancreas.

A 72-year-old man with recurrent pancreatitis and a horseshoe-shaped anomaly of the pancreas is described. The diagnosis was made by endoscopic retrograde cholangiopancreatography (ERCP) and computed tomography scan; laparotomy was confirmatory. The abnormal duct branched to the lower left from an enlarged Santorini's duct; a thin Wirsung's duct was joined at its distal portion to the junction of the abnormal duct. The anomaly was associated with a cystic dilatation of the common bile duct with stone and cholecystolithiasis. This anomaly is considered to be a variation of the dominant dorsal duct syndrome.

Aged↗
PubMed1992

Serum protease inhibitor capacity for elastase and the severity of pancreatitis.

To clarify the relationship between the diminution of the serum protease inhibitor capacity and the severity of pancreatitis, the binding capacity of serum protease inhibitors for exogenous elastase 1 (E1) was investigated by gel filtration, the elastase activity of the alpha 2-macroglobulin (alpha 2-M)-elastase complex was measured, and the relationship between these findings and the severity of pancreatitis was studied in 13 patients with pancreatic disease and 6 healthy subjects. When 125I-labeled E1 was added to the sera of healthy subjects, it bound to alpha 2-M and alpha 1-protease inhibitor (alpha 1-PI) with a mean ratio of 72:28. In mild acute pancreatitis (n = 5), the binding capacity of alpha 2-M was less than that in healthy subjects. In severe pancreatitis (n = 4), most of the exogenous E1 bound to alpha 1-PI (alpha 2-M vs. alpha 1-PI, 13:87). This diminution in the binding capacity of alpha 2-M correlated well with the severity of acute pancreatitis. In the sera of patients (n = 4) with pancreatic cancer containing much immunoreactive E1, the proportion of exogenous E1 bound by alpha 2-M and alpha 1-PI (25:75) was similar to that seen in severe acute pancreatitis. A significant inverse relationship between the binding capacity of alpha 2-M and the activity of the endogenous elastase bound to alpha 2-M was seen in various pancreatic diseases.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗
PubMed1991

Alteration of cholecystokinin receptor binding after caerulein-induced pancreatitis in rats.

The alteration of CCK receptor binding on the pancreatic acini in vitro following the induction of pancreatitis was investigated in male rats. Pancreatitis was induced by administering 5 intraperitoneal injections of caerulein, 40 micrograms/kg each at hourly intervals. The uptake of [3H]-thymidine in the pancreatic acini increased on day 7 following caerulein administration. The release of amylase stimulated by CCK-8, and CCK receptor analysis using bioactive [125I]-BH-CCK-8, were performed at regeneration stage, on days 14 and 28 following the injections. The maximal release of amylase stimulated by CCK-8 was reduced on day 14 by about 40% and recovered on day 28. On day 14 there was a decrease of 60% in the number of high-affinity receptors and an increase of 161% in the number of low-affinity receptors. On day 28 there was a 128% increase in the number of low-affinity receptors. Accordingly, we suggest that the CCK receptors of the regenerating cells following caerulein-induced pancreatitis differ from those of the intact cells.

Amylases↗
PubMed1991

Properties of hydroxyapatite-coated Ti-6Al-4V alloy produced by the ion-plating method.

To improvement the brittleness of hydroxyapatite (HAp) coated on titanium alloy (Ti-6Al-4V), a thin ceramic layer was formed by means of the RF ion-plating method. The alloy substrates were coated with HAp at 1, 3 or 5 microns thickness and heat-treated at 500 degrees C for 4 hours. Properties of HAp-coated alloy were evaluated by characterization of the ceramic films both before and after heat-treatment, as well as by bending, electrochemical and dissolution tests. HAp-coated film had a slightly higher Ca/P ratio than the original material and was stoichiometrically Ca10(PO4)6(OH)2 by EPMA analysis. HAp was mainly recognized crystallographically by XRD analysis of the films after heat treatment, though it was hardly recognized on before heat-treatment film. These coated materials had a residual strain ranging from 0.3 to 0.7% without causing cracks in the HAp films with the three-point bend testing. Electrochemically, it was confirmed that the corrosion resistance of the Ti alloy was improved by any coating process. The amounts of Ca released from HAp coated film in 0.9% NaCl solution tended to increase with films that were 3 and 5 microns in thickness, but there were no significant differences in Ca released from film before and after heat treatment.

Aluminum Oxide↗
PubMed1991

Characteristic behavior of serum elastase 1 in pancreatic cancer.

Diagnostic significance of serum immunoreactive elastase 1 (IRE) in pancreatic cancer was evaluated in 53 patients with pancreatic cancer. Frequency of abnormally high serum IRE levels in pancreatic cancer was 66.0%; 87.0% in head cancer (N = 23), 55.0% in body & tail cancer (N = 20) and 40% in diffuse cancer (N = 10). Serum IRE level in resectable cancer was significantly higher than that in unresectable cancer. Comparative studies of serum pancreatic enzymes revealed that serum IRE was the most sensitive marker for diagnosis of pancreatic cancer. The characteristic behavior of serum IRE throughout the course of pancreatic cancer was that abnormally high levels of IRE are maintained for a longer period of time when compared to that of pancreatitis. In the comparative study of serum IRE and CA19-9, of the 9 cases of pancreatic cancer with CA19-9 levels less than 100U/ml, 7 showed abnormally high values of IRE, and of these 4 were resectable. These results indicate that in order to detect early pancreatic cancer, any elevation of serum IRE before CA19-9 increase should be noted with care, and patients who particularly show elevated IRE values for more than one month should be subjected to more extensive morphological examinations.

Adult↗
PubMed1990

The pattern design for evaluation of castability of nickel-chromium alloys.

To find a pattern design that would provide a higher degree of discrimination for castability of nickel-chromium alloys using a polyester sieve cloth pattern, four shaped patterns were chosen. The results as calculated by t-test indicated that patterns No. 2 and No. 3 can discriminate the castability of nickel-chromium alloys over almost the total range of the casting temperatures, but that pattern No. 3 is a better discriminator for the castability. Pattern No. 1 can only discriminate the castability at lower casting temperatures. Pattern No. 4 can only discriminate the castability at higher casting temperatures. The percent castability value calculated from the number of complete square segments and the areas of the four patterns are highly linear correlations, so it is reasonably accurate to calculate the castability only from counting the number of complete square segments. Beryllium-containing nickel-chromium alloy is more castable than non-beryllium-containing alloy and the higher casting temperatures appear to result in better castability.

Beryllium↗
PubMed1990

A study of the method of making dental prosthetic appliances by sintered titanium alloys: effect of copper powder content on properties of sintered titanium alloy.

The effects of added copper powder to the properties of the sintered titanium alloys were investigated by measuring the compressive strength and densities of the green and sintered compacts, the thermal expansion curves and dimensional changes in the sintered compacts, and the accuracy of the crown-type restorations. The compressive strengths of green compacts ranged from 55 to 75 MPa. The expansion of green compacts increased with increased copper content. The sintered density was lower than the green density. The compressive yield strength of sintered compacts ranged from 260 MPa to 410 MPa. The sintered compacts expanded from 0.35% to 1.03% and the expansion increased with increased copper content. The dimensional accuracy of crown-type restorations showed the same dimensional change tendencies as did the sintered compacts. These results showed that the fit and the strength of sintered titanium alloy restorations could be improved.

Copper↗
PubMed1990

[The study on surface porosity of die stone. Influence of vinyl polysiloxane impression materials].

In this study, the authors have attempted to discover optimum conditions for eliminating all porosity, except what is caused by manual error, in the surfaces of Die Stone. Five vinyl-porisiloxane impression materials, two other kinds rubber impression materials, and two kinds of die materials were used. Die materials were poured at intervals of 0, 15, 30, 60, and 120 minutes after the impression had been removed. Cast-surface porosity was measured by means of SPICCA II. Results 1. Practically surface porosities were not scarcely observed in casts made from any of the impression materials except vinyl silicone rubber. Among the five vinyl-polysiloxane impression materials, Hydrophilic Exaflex produced the least porosity. 2. Porosity in casts made with Provil tended to decrease definitely as pouring time progressed. This tendency occurred with no other materials. 3. When the die material was mixed at a low water-powder ratio, cast-surface porosity was reduced in the case of all materials except President. 4. Concentration of hydrogen gas, which was released from all vinyl-polysiloxane impression materials, decreased with the passing of time. 5. In the case of Provil, a correlation existed between hydrogen-gas concentration and the degree of cast-surface porosity. But no similar correlation was observed in the case of any other vinyl-polysiloxane impression materials.

Dental Impression Materials↗
PubMed1990

[Corrosion of dental titanium alloys binary system of Ti-Al, Ti-Cu, Ti-Ni].

Anodic polarization, natural electrode potential, polarization resistance, tarnish, weight change and metal component dissolution in artificial saliva, of Ti-Al, Ti-Cu and Ti-Ni binary alloys were investigated to determine the effects of the added elements on the corrosion characteristics. In the case of Ti-5 at % Al to Ti-50 at % Al system alloys, increase in the aluminum content of the alloys raised the corrosion resistance. However pitting corrosion presumed at an aluminum content of more than 10 at %. In the case of the Ti-5 at % Cu to Ti-70 at % Cu system alloys, increase in the copper content of the alloys decreased the corrosion resistance and the decrease was marked at a copper content of more than 50 at %. In the case of Ti-5 at % Ni to Ti-70 at % Ni system alloys, 50 at % Ni was estimated to be the maximum content to keep corrosion resistance of the titanium alloys.

Aluminum↗
PubMed1989

[The usefulness of Chlamydia testpack for the diagnosis of Chlamydia trachomatis infection in genito-urinary tract].

A comparative study between Chlamydia Testpack and Chlamydiazyme for the detection of chlamydial antigen was performed. In 61 cases suspected of being chlamydial infection, Chlamydia Testpack had a specificity of 92% and a sensitivity of 88% when compared with Chlamydiazyme. On the result of study using Chlamydia trachomatis serotype B, the sensitivity of Chlamydia Testpack which had a lower limit of 6 x 10(4)/ml of EB was less than that of Chlamydiazyme which had a lower limit of 0.7 x 10(4). However, the large number of EB presented in almost all positive specimen, indicated that Chlamydia Testpack could be used to screen the clinical materials.

Adolescent↗