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T Uchida

Publications and source records attributed to T Uchida.

At least 451 records · Page 25Linked to original sources
PubMed1995

Can simple radiographs be predictive of total hip dislocation?

The usefulness of angles measured on standardized radiographs to determine acetabular position and predict dislocation after primary total hip arthroplasty (THA) was reviewed retrospectively. Seventy-four patients (97 primary THAs) were reviewed. All patients underwent a standardized protocol of postoperative radiographs which included an anteroposterior view of the pelvis and a cross-table lateral radiograph of the hip. Two angles were measured to define acetabular position: the abduction angle was measured on the anteroposterior radiograph and the version angle was measured on the cross-table lateral radiograph. The values for these angles were compared in a group of known dislocating THAs (7 hips) and a control group of stable THAs (90 hips). These radiographic measurements were also assessed for their reproducibility. The values for the abduction and version angles were not significantly different between the two groups. The values for abduction and version angles for a given hip, from one examination to another, were reproducible. Neither the abduction nor the version angle was a predictor of dislocation.

Biomechanical Phenomena↗
PubMed1995

Effect of ileo-jejunal transposition on the growth of the GI tract and pancreas in young and aged rats.

BACKGROUND: Ileo-jejunal transposition (IJT; transposition of the distal quarter of the small intestine into the proximal jejunum) is known to stimulate mucosal growth of the transposed ileum, but the effects on other parts of the small intestine are controversial. The effect of aging on the trophic action of IJT is not known. METHODS: We examined the trophic effect of IJT (3 weeks post-operation) on the gastrointestinal tract and pancreas, and on plasma levels of neurotensin and gastrin in three different aged groups of Fischer 344 rats (4, 12, and 24 months old). RESULTS: Three weeks after IJT, the mucosal mass, villus height, and crypt depth increased significantly in the transposed ileum as well as in the remainder of the small intestine. The weights of the colon and pancreas increased significantly after IJT. These responses were not affected by aging. In each of the three age groups, IJT did not affect plasma gastrin level, but significantly increased plasma level of neurotensin. CONCLUSIONS: The distal ileum appears to play an important role in the regulation of growth in the intestine and pancreas; this role is preserved in aged rats. Neurotensin may play an important role in this mechanism.

Aging↗
PubMed1995

Evidence for cdk5 as a major activity phosphorylating tau protein in porcine brain extract.

The major kinase capable of phosphorylating tau in a porcine brain extract was suggested to be a brain cdc2-like kinase, called cdk5. Tau protein components of microtubules assembled in the brain extract using ATP were phosphorylated to a higher level, and showed a slower electrophoretic mobility than those assembled with GTP. Most of this phosphorylation and electrophoretic mobility shift, that occurred in the brain extract incubated with ATP, were inhibited by butyrolactone I, a specific inhibitor of cdc2 kinase and cdk5. Further, butyrolactone I inhibited phosphorylation of tau exogenously added to the brain extract by approximately 70%. cdk5 purified from porcine brain decreased the electrophoretic mobility of dephosphorylated tau by in vitro phosphorylation of tau to the level present in microtubules polymerized with ATP. cdc2 kinase purified from starfish oocytes also phosphorylated tau and shifted its electrophoretic mobility to an extent greater than that obtained with cdk5. Western blot analysis showed that cdc2 kinase phosphorylated epitopes recognized by SMI31, 33, 34, and tau 1 antibodies in tau proteins , while cdk5 phosphorylated the site recognized by SMI33 (corresponding to phosphorylation at Ser235 in the longest human tau isoform) and partially phosphorylated the tau 1 site. Phosphorylation experiments performed on tau in brain extracts, in the presence of okadaic acid, suggested the presence of both okadaic acid-sensitive and -insensitive phosphatases acting on phosphorylated Ser235. Rat tau that was prepared immediately after decapitation showed a similar phosphorylation state to tau in microtubules polymerized with ATP, suggesting that tau is relatively phosphorylated in vivo.

4-Butyrolactone↗
PubMed1995

Mixed venous oxygen saturation during cardiopulmonary bypass poorly predicts regional venous saturation.

Mixed venous oxygen saturation is generally accepted as an indicator of adequacy of systemic oxygen delivery; however, cardiopulmonary bypass (CPB) may alter this relationship. Major postoperative complications potentially secondary to inadequate oxygen delivery during CPB indicate that mixed venous oxygen saturation may not detect regional venous desaturation during CPB. We therefore tested the hypothesis that mixed venous oxygen saturation and pH did not predict regional venous oxygen saturations and pH during 2 h of bypass in a swine model. Six immature swine (27-34 kg) received standard normothermic CPB. Sagittal sinus and portal vein oxygen saturations and blood gases were measured at 30, 60, 90, and 120 min of bypass. Although the venous reservoir oxygen saturation remained unchanged during 2 h of bypass, sagittal sinus saturation and pH decreased significantly (66% +/- 3.3% to 33% +/- 2.2% and 7.38 +/- 0.04 to 7.23 +/- 0.05, respectively). Likewise in the portal vein, oxygen saturation and pH also decreased (82% +/- 2.4% to 59.3% +/- 3.9% and 7.39 +/- 0.03 to 7.27 +/- 0.06, respectively). We conclude that profound regional venous desaturation and progressive regional acidemia may go undetected even when a standard pump flow rate of 100 mL.kg-1.min-1 is used and mixed venous oxygen saturation is normal.

Animals↗
PubMed1995

Trophic response of gut and pancreas after ileojejunal transposition.

OBJECTIVE: The authors determined whether ileojejunal transposition (IJT) stimulates the growth of the pancreas or the nontransposed segment of small intestine, and ascertained whether this trophic effect is altered by the location of transposed gut segment. SUMMARY BACKGROUND DATA: Transposition of the ileum to the proximal small intestine stimulates a marked mucosal growth of the transposed ileal segment; the cellular mechanisms responsible for this adaptive hyperplasia are not known. METHODS: The distal quarter of the small intestine (distal ileum) was transposed into the proximal (Type I), middle (Type II), or distal (Type III) portions of the remaining small intestine. On postoperative day 28, the pancreas and scraped mucosa from the segments of transposed ileum, proximal ileum, and duodenum were obtained, weighed, and examined for DNA and protein content. RESULTS: All types of IJT increased mucosal weight and DNA content of the transposed ileum. Types I and II IJT produced a significant proliferation of the pancreas and mucosa of the duodenum and proximal ileum. The magnitude of proliferative increases was greatest in Type I IJT. CONCLUSIONS: Ileojejunal transposition appears to be an excellent model to examine the mechanisms by which intestinal epithelial cells proliferate in response to luminal nutrients or humoral factors.

Adaptation, Physiological↗
PubMed1995

Increasing organ blood flow during cardiopulmonary bypass in pigs: comparison of dopamine and perfusion pressure.

OBJECTIVE: To determine whether low-dose dopamine infusion (5 micrograms/kg/min) during cardiopulmonary bypass selectively increases perfusion to the kidney, splanchnic organs, and brain at low (45 mm Hg) as well as high (90 mm Hg) perfusion pressures. DESIGN: Randomized crossover trial. SETTING: Animal research laboratory in a university medical center. SUBJECTS: Ten female Yorkshire pigs (weight 29.9 +/- 1.2 kg). INTERVENTION: Anesthetized pigs were placed on normothermic cardiopulmonary bypass at a 100-mL/kg/min flow rate. After baseline measurements, the animal was subjected, in random sequence, to 15-min periods of low perfusion pressure (45 mm Hg), low perfusion pressure with dopamine (5 micrograms/kg/min), high perfusion pressure (90 mm Hg), and high perfusion pressure with dopamine. Regional perfusion (radioactive microspheres) was measured in tissue samples (2 to 10 g) from the renal cortex (outer two-third and inner one-third segments), stomach, duodenum, jejunum, ileum, colon, pancreas, and cerebral hemispheres. MEASUREMENTS AND MAIN RESULTS: Systemic perfusion pressure was altered by adjusting pump flow rate (r2 = .61; p < .05). In the kidney, cortical perfusion pressure increased from 178 +/- 16 mL/min/100 g at the low perfusion pressure to 399 +/- 23 mL/min/100 g at the high perfusion pressure (p < .05). Perfusion pressure augmentation increased the ratio of outer/inner renal cortical blood flow from 0.9 +/- 0.1 to 1.2 +/- 0.1 (p < .05). At each perfusion pressure, low-dose dopamine had no beneficial effect on renal perfusion or flow distribution. Similar results were found in the splanchnic organs, where regional perfusion was altered by perfusion pressure but not by dopamine. In contrast, neither changing perfusion pressure nor adding low-dose dopamine altered blood flow to the cerebral cortex. CONCLUSIONS: These data indicate that the lower autoregulatory limits of perfusion to the kidneys and splanchnic organs differ from those limits to the brain during normothermic bypass. Selective vasodilation from low-dose dopamine was not found in renal, splanchnic, or cerebral vascular beds. Increasing the perfusion pressure by pump flow, rather than by the addition of low-dose dopamine, enhanced renal and splanchnic but not cerebral blood flows during cardiopulmonary bypass.

Animals↗
PubMed1995

Limiting initial resuscitation of uncontrolled hemorrhage reduces internal bleeding and subsequent volume requirements.

We tested the hypothesis that full or "standard resuscitation" (SR) with lactated Ringer's solution (LRS) results in increased bleeding in uncontrolled hemorrhagic shock, compared with a "limited prehospital resuscitation" (LPR) regimen and a control group of "no resuscitation" (NR). Cardiac output was used as physiological endpoint for resuscitation. Twenty swine had 25 mL/kg of blood withdrawn during a 30-minute controlled hemorrhage, followed by a 20-minute "prehospital" resuscitation regimen was conducted in three groups: the SR group (n = 6), LRS infused as needed to restore cardiac index (CI) to 100% baseline; the LPR group (n = 8), with resuscitation using LRS to 60% of baseline CI, with volume limited to 10 mL/kg; and the NR group (n = 6). After aortotomy repair, intraoperative resuscitation was continued for 120 minutes using LRS to achieve and maintain 80% of baseline mean arterial pressure. Blood pressure and cardiac index were greatly reduced, to 34% and 39% of baseline, respectively, by hemorrhage. During prehospital resuscitation, the SR group required 48.8 +/- 6.5 mL/kg of LRS, whereas the LPR group received 9.4 +/- 0.6 mL/kg (p < 0.05). Mean arterial pressure increased in all three groups during prehospital resuscitation (p < 0.05). Pulse pressures increased in the SR and LPR groups only (p < 0.05). The increment in oxygen delivery was significantly greater in the SR group, compared with the LPR group (p < 0.05), which in turn was significantly greater than the NR group (p < 0.05). Peritoneal blood volume was significantly higher in the SR group (20.6 +/- 5.6 mL/kg), versus the LPR (7.3 +/- 1.3 mL/kg; p < 0.05) and NR groups (3.0 +/- 0.9 mL/kg; p < 0.05). Crystalloid and whole blood requirements during the intraoperative resuscitation phase were significantly higher in the SR group (193 +/- 16.0 and 9.0 +/- 2.5 mL/kg), than in LPR (111.8 +/- 15.6 and 4.5 +/- 1.8 mL/kg; p < 0.05) and NR groups (128.5 +/- 32.3 and 3.9 +/- 2.3 mL/kg; p < 0.05). In the presence of uncontrolled hemorrhagic shock, LPR and NR can significantly reduce internal hemorrhage and subsequent intraoperative crystalloid and blood requirements.

Animals↗
PubMed1995

Cross-reactivity of Rickettsia japonica and Rickettsia typhi demonstrated by immunofluorescence and Western immunoblotting.

Cross-reactivity between Rickettsia japonica and R. typhi was observed by immunofluorescence tests using sera from patients with Oriental spotted fever (OSF), from whom the causative agent was isolated and identified as R. japonica. Western immunoblotting with these sera revealed that only the 120-kilodalton surface polypeptide, i.e., rickettsial outer membrane protein (rOmp) B, has a common antigenicity with the 105-kilodalton surface polypeptide of R. typhi. In some cases, antibodies specifically reactive with R. typhi were detected in acute-phase sera followed by a significant rise in titers, possibly because of an anamnestic response to a previous infection with an R. typhi-like agent; the sera retained reactivity to R. typhi even after absorption by a homologous strain. A lipopolysaccharide (LPS)-like antigen of R. typhi was found to be reactive with some sera of OSF patients. The ladder bands on Western immunoblot of rickettsial organisms were confirmed to be polysaccharide in nature, which was demonstrated by comparing them with the pattern of silver-stained gel of proteinase K-treated rickettsial specimens after sodium dodecyl sulfate-polyacrylamide gel electrophoresis.

Antibodies, Bacterial↗
PubMed1995

Age-related changes in cerebral and peripheral monoamine contents in stroke-prone spontaneously hypertensive rats.

1. We examined monoamine contents in various regions of the brain and catecholamine contents in the heart and the adrenal gland of stroke-prone spontaneously hypertensive rats (SHRSP) and Wistar-Kyoto (WKY) rats aged 1.5, 3 and 6 months. 2. The noradrenaline (NA) content and the 5-hydroxytryptamine (5-HT) content in the brainstem were larger in 1.5 month old SHRSP than in the age-matched WKY. In addition, at age 6 months the brainstem 5-HT content was higher in SHRSP than in WKY. 3. The NA and 5-HT contents in basal ganglia, thalamus, hypothalamus, septum and anterior and lateral cerebral cortex showed no significant difference between SHRSP and WKY at any age. 4. The dopamine (DA) contents in all brain regions examined did not differ between WKY and SHRSP at any age. 5. The NA contents in left and right ventricles were larger in 3 month old SHRSP than in the age-matched WKY, but were lower in 6 month old SHRSP than in the age-matched WKY. The cardiac DA contents did not differ between the two rat strains of any age. 6. The adrenal NA and adrenaline (A) contents in 6 month old SHRSP were significantly larger than those in the corresponding WKY. 7. These findings suggest that the increased NA and 5-HT contents in the brainstem may be related to the onset of hypertension, and that the altered cardiac NA contents and adrenal NA and A contents change as a result of the onset or persistence of hypertension.

Adrenal Glands↗
PubMed1995

Small hepatocellular carcinoma: its relationship to multistep hepatocarcinogenesis.

Recent advances in imaging techniques have led to the discovery of small hepatocellular carcinomas (HCC). The small HCC most often exhibit low-grade malignant (LGM) or extremely well differentiated features, which are different from those of advanced, full-blown HCC. The LGM-HCC present a serious diagnostic challenge to pathologists and must be differentiated from benign (reactive) and atypical (borderline) hyperplastic nodules. Analysis of small HCC revealed that hepatocarcinogenesis frequently occurs stepwise from atypical hyperplasia to LGM-HCC and subsequently to advanced HCC. The HCC arise in irregular regeneration in chronic liver disease and in the essentially normal liver after steroid administration. Although the tumor suppressor gene, p53, is revealed to be often mutated in advanced HCC, the genetic events corresponding to each stage of multistep hepatocarcinogenesis are not clarified at all.

Anabolic Agents↗
PubMed1995

Type La glycogen storage disease with focal nodular hyperplasia in siblings.

Glycogen storage disease type I (GSD-I) is an inherited disorder that is due to a glucose-6-phosphatase (G6Pase) deficiency. There have been recent reports of hepatocellular tumors in adults with this disease. Hepatic adenoma is the most common tumor described but others, including hepatocellular carcinomas, hepatoblastomas, and focal nodular hyperplasia (FNH) have been reported. FNH of the liver is a rare benign lesion that has been reported in eight patients with GSD-I. Three of these eight patients, in addition to the patient in our study, had been treated with portacaval shunts. When these patients were compared with patients who had not received such treatment, it appeared that the portacaval shunts may have induced the development of FNH and may have been associated with earlier complications. FNH is a benign tumor that may coexist with adjacent fibrolamillar carcinomas and/or adenomas and requires careful follow-up.

Child↗
PubMed1995

Assessment of sextant biopsy of the prostate for detecting cancer prior to therapy in patients clinically diagnosed as benign prostatic hyperplasia.

Pathological results and perioperative morbidity were compared in 199 patients who had undergone prostatectomy and/or biopsy in order to determine the extent to which systematic biopsy is effective for detecting prostate cancer prior to therapy in patients clinically diagnosed as having benign prostatic hyperplasia. Seventeen (8.5%) cancers were detected in 199 patients following surgery and/or biopsy. Digitally-guided biopsy as a means of detecting prostate cancer was found to be just as effective as ultrasound-guided biopsy. Seven (12.5%) cancers were detected in 56 patients who had undergone biopsy and transurethral resection. Preprostatectomy biopsy detected only two of three patients with stage T1b disease. All four stage T1a and one stage T1b failed to be diagnosed. Of 90 patients who had biopsy prior to surgery other than TURP, seven (7.8%) cancers were found. Four of these were advanced. The incidence of postoperative fever > 38.0 degrees C and duration of postoperative pyuria did not differ significantly between groups with or without biopsy. Preoperative biopsy did not contribute to perioperative morbidity. Tumors detected by systematic biopsy are usually large and clinically significant. Positive biopsy results are often diagnostic, but the pathological features of a tumor together with clinical parameters should be considered to reduce the chance of overdiagnosing an insignificant tumor. Sextant biopsy would be most applicable to patients scheduled for any type of therapy other than TURP especially in those with markedly elevated serum PSA levels. This procedure may be beneficial particularly for younger patients with long life expectancy who will benefit from definitive therapy.

Aged↗
PubMed1995

High intensity focused ultrasound for benign prostatic hyperplasia.

BACKGROUND: Transurethral resection of the prostate (TURP) has been the gold standard of treatment for patients with symptomatic benign prostatic hyperplasia (BPH). The present paper discusses the safety and effectiveness of transrectal high intensity focused ultrasound (HIFU) for treating patients with symptomatic BPH. METHODS: HIFU was conducted on 28 patients with BPH. At one, three and six months after treatment, all patients were examined for parameters including International Prostate Symptom Scores (I-PSS), Quality of Life (QOL) inquiry, uroflowmetry, and transrectal ultrasound for determining prostate volume. RESULTS: I-PSS and QOL showed statistically significant improvement at one, three, and six months postoperatively (P < 0.0001-0.005, Wilcoxon signed-rank test). Ten of 28 (35.7%), 13 of 28 (46.4%), and 6 of 15 (40.0%) cases were categorized as effective cases with HIFU treatment at one, three, and six months follow-up. CONCLUSIONS: Focused ultrasound is an exciting new technology by which tissue can be destroyed at a site distant from the source of energy without damage to surrounding tissue. Clinical experience with alternative power settings, more accurate spacing of treatment lesions, and further development of HIFU machines may improve the results. Longer follow-up of patients with further clinical evaluation of HIFU is necessary to define the efficacy of this technique.

Aged↗
PubMed1995

Prostate-specific antigen in mass screening for carcinoma of the prostate.

BACKGROUND: Prostate-specific antigen (PSA) has various advantages over prostatic acid phosphatase (PAP) as a marker for prostate cancer, but its role in prostate cancer mass screening remains controversial. We measured serum PSA in addition to serum PAP determination and digital rectal examination (DRE) in our mass screening program to assess the usefulness of PSA for prostate cancer mass screening. METHODS: Serum PSA and PAP measurements and DRE were performed in 1249 patients in mass screening for carcinoma of the prostate in 1989 and 1990. Thirteen cancers were diagnosed. We calculated the mean plus standard deviations (2SD) of the PSA and PAP values of men without cancer, and assessed the usefulness of PSA for prostate cancer screening by using these figures as the upper limit of normal. RESULTS: The number positive for PSA, PAP and DRE were 39, 36 and 48, respectively. If our screening had been performed without DRE, three cancers would have remained undetected, and the number would have been the same if performed without PSA. If the screening had been performed without PAP, on the other hand, no cancers would have remained undetected. The sensitivities of PSA and PAP were 54% and 23%, respectively. The screening detection rate with DRE and PSA was 0.88%, and with DRE and PAP was 0.64%. CONCLUSIONS: Measurement of serum PSA values with adjustment of the cut-off value was considered more useful than PAP in mass screening for prostate cancer.

Acid Phosphatase↗
PubMed1995

Particle size studies for subcutaneous delivery of poly(lactide-co-glycolide) microspheres containing ovalbumin as vaccine formulation.

The primary objectives of the present study were to produce poly(lactide-co-glycolide) (PLGA) microspheres with different diameters, to characterize these microspheres which were loaded with a model antigen, ovalbumin and to evaluate the effect of microsphere particle size on the serum antibody levels following administration to mice. Four kinds of ovalbumin-loaded PLGA microspheres with different diameters (1.2, 3.5, 7.0 and 14.3 microns as mean volume diameter) were manufactured by a w/o/w emulsion/solvent evaporation method. Low loading percent (0.08%-0.25% w/w) and efficiencies (8-25% w/w) were observed. Examination using scanning electron photomicrographs showed smooth spherical particles. The in-vitro release of ovalbumin from microspheres showed an expected burst release with all batches and the extent of the burst release increased with decreasing diameters of spheres; PLGA microspheres with the smallest diameter (1.2 microns) showed an 80% burst release within one day. Approximately 10-60% of ovalbumin remained unreleased 30 days later. The single subcutaneous administrations of ovalbumin-loaded PLGA microspheres with different diameters to mice induced good antibody responses above ovalbumin saline negative controls at 3, 6, 9, and 12 weeks after inoculation. Especially, 0.16% ovalbumin-loaded PLGA microspheres having mean volume diameter of 3.5 microns exhibited the best immune responses with values greater than those obtained after inoculation with adjuvants such as complete Freund's adjuvant or alum as positive control. The strong adjuvant activity of PLGA microspheres as vaccine formulation was suggested.

Alum Compounds↗
PubMed1995

[Serosurvey for spotted fever group rickettsial infection in vertebrates in Shimane Prefecture].

We carried out a survey for the prevalence of antibodies to the spotted fever group (SFG) rickettsia in vertebrates such as dogs, cattle, deer, and mice in Shimane Prefecture. Rickettsia japonica was employed as antigen in indirect immunofluorescence (IF) tests. The experiment for natural infections using decoy animals was performed in the field of the endemic area. 1. Among 115 street dogs, 18.3% possessed the antibodies against SFG rickettsia, while all of the 8 hunting dogs had the antibodies. 2. Among 234 cattle tested, 17.9% possessed the antibodies. IF titers were 1:40 to 1:160 (mean 1:68). 3. Among 69 wild deer, 92.7% possessed the antibodies ranging between 1:40 and 1:640, which showed the highest IF titers (mean 1:89) among those of the examined vertebrates. 4. The incidence of the antibodies in Apodemus speciosus, Apodemus argenteus and Eothenomys smithi smithi mice were 16.5, 4.3 and 0%, respectively. The incidence of the antibodies against SFG rickettsia in mice captured in the endemic area was significantly higher (22.8%) than that in non-endemicarea (10.4%). Difference in the incidence of antibody-positive mice was also observed within the endemic area. Therefore, we concluded that the infection of mice was restricted to a limited area. 5. No significant rise in IF titers was observed in decoy animals that had been infested with ticks in the endemic area.

Animals↗
PubMed1995

Detection of Rickettsia japonica in Haemaphysalis longicornis ticks by restriction fragment length polymorphism of PCR product.

PCR was applied to the detection of Rickettsia japonica, the causative agent of Oriental spotted fever (OSF), in ticks collected at two sites of the Muroto area on Shikoku Island, a major area in Japan where OSF is endemic. Primer pair Rr190.70p and Rr190.602n of the R. rickettsii 190-kDa antigen gene sequence of Regnery and others (R.L. Regnery, C.L. Spruill, and B.D. Plikaytis, J. Bacteriol. 173:1576-1589, 1991) primed the DNA extracted from Haemaphysalis longicornis ticks but not those extracted from Haemaphysalis formosensis, Haemaphysalis flava, Haemaphysalis hystricis, or Amblyomma testudinarium ticks. Digestion of the amplification product with the restriction endonucleases PstI and AluI produced the restriction fragment length polymorphism pattern specific to R. japonica. The HindIII and MspI digests gave restriction fragment length polymorphism patterns identical to those of the PCR product from R. japonica DNA. Hemolymph preparations of H. longicornis ticks were demonstrated to contain rod-shaped organisms that were detected by immunofluorescence with the monoclonal antibody specific to R. japonica species. The primer pair did not amplify the DNA of a laboratory colony of H. longicornis ticks originally collected at an area where OSF is not endemic. Our results provided evidence that H. longicornis ticks might be an arthropod reservoir for R. japonica and a vector of OSF.

Animals↗