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Biomedical subjects

K Oshima

Publications and source records attributed to K Oshima.

At least 19 recordsLinked to original sources
PubMed1995

Calcium-induced platelet aggregation in washed platelets from guinea pigs.

The present study investigated the effects of extracellular calcium on washed platelets of guinea pigs, rabbits, rats and humans. CaCl2 without agonists induced platelet aggregation in guinea pigs and rabbits, but not in rats or humans. CaCl2 increased platelet [Ca2+]i in Fura-2-loaded guinea pig platelets. Calcium-induced platelet aggregation was inhibited by W-7 (a calmodulin antagonist), aspirin, indomethacin, TMB-8 (an inhibitor of intracellular Ca2+ release) and also nicardipine (a calcium antagonist). These data suggest that CaCl2-induced platelet aggregation is mediated by calmodulin, cyclooxygenase and other, as yet unknown, mechanisms.

Animals↗
PubMed1995

Metal-characterization of N-acyl-D-glutamate amidohydrolase from Pseudomonas sp. strain 5f-1.

N-Acyl-D-glutamate amidohydrolase (D-AGase) from Pseudomonas sp. 5f-1 was a zinc-metalloenzyme which contained 2.06-2.61 g.atom of Zn per mole of enzyme. The zinc atom was required for the catalytic activity and stability of the enzyme. The N-terminal amino acid sequence of Pseudomonas sp. 5f-1 D-AGase showed 32% identity to that of Alcaligenes xylosoxydans subsp. xylosoxydans A-6.

Amidohydrolases↗
PubMed1995

Laryngeal function in postpolio patients.

Of the 250,000 survivors of the polio epidemics, approximately 25% experience progressive muscle weakness known as postpolio syndrome (PPS). Laryngeal function in postpolio patients previously has not been studied. This paper presents data detailing laryngeal function in a group of postpolio patients who had been evaluated for swallowing complaints. Nine patients underwent comprehensive history and physical exam, acoustical voice analysis, and laryngeal videostroboscopic endoscopy. Three patients underwent laryngeal electromyography (EMG) evaluation. Results indicated some degree of phonatory or laryngeal deficit in all subjects. Subjects with dysphagia also demonstrated vocal fold paralysis. EMG revealed decreased recruitment and increased amplitude, findings consistent with EMG studies in skeletal muscle in postpolio patients. Results suggest that postpolio patients who complain of swallowing difficulties are at risk for laryngeal pathology.

Aged↗
PubMed1995

[A case of hemophagocytic syndrome manifesting adult Still's disease and acute hepatitis].

We report a 20 year-old woman with hemophagocytic syndrome. In February 1993, she developed high fever, arthralgia, salmon-like pink eruption, leukocytosis and splenomegaly. She was diagnosed as adult Still's disease and successfully treated with intravenous immunoglobulin and oral prednisolone. In September 1993, she was re-admitted to our hospital complaining of general fatigue and low grade fever and treated with oral prednisolone at a daily dose of 15 mg. On October 2, 1993, she suddenly developed high fever and salmon-like pink eruption on her leg followed by the marked increase of serum transaminase and LDH levels (GOT 3,270 IU/l, GPT 1,880 IU/l, LDH 5,480 IU/l) on October 7. Since hepatic failure progressed, we started methylprednisolone pulse therapy and plasmapheresis. However, because of the progression of pancytopenia caused by hemophagocytosis, the treatment with VP-16 was initiated. However, she died of DIC on November 2, 1993. Autopsy revealed submassive necrosis of the hepatocytes with moderate infiltration of histiocytes. She was retrospectively diagnosed as hemophagocytic syndrome whose manifestations are very similar to those in adult Still's disease and acute viral hepatitis.

Acute Disease↗
PubMed1995

[A study of vitreous liquefaction using in vitro models--1. The effect of plasma on vitreous liquefaction].

To study the mechanism of vitreous liquefaction following vitreous hemorrhage, an in vitro study was done. We isolated whole vitreous gel of pig eyes, then weighed, incubated it with sample solution and shook it at room temperature. The ratio of weight loss after shaking to initial weight were calculated as vitreous liquefaction rate (VLR). There was no significant difference in VLR between samples incubated with whole blood (50.7%) and with plasma (48.8%), and it was significantly higher than control incubated with isotonic phosphate buffered physiological saline (PBS)(14.8%) after 24 hours shaking. There were no significant differences between control and samples incubated with blood cells (21.1%) and with hemoglobin (20.5%). The VLR of samples incubated with plasma gradually increased with time whereas controls incubated with PBS showed no changes until 24 hours. The VLR and concentration of plasma were highly correlated. These results indicated that contact of plasma with vitreous gel encourages liquefaction possibly by enzymatic digestive action with proteases.

Animals↗
PubMed1994

Primary central nervous system lymphomas. Immunophenotypic, virologic, and cytogenetic findings of three patients without immune defects.

BACKGROUND: Primary central nervous system (PCNS) lymphoma is a relatively rare disease, but an increasing incidence is reported. The Epstein-Barr virus (EBV), which is often found in lymphomas of immunocompromised patients, has been implicated in the development of lymphomas. Many cytogenetic analyses of nodal B cell lymphomas have been performed, but few studies on PCNS lymphomas have been reported. METHODS: The detection of EBV genome using the polymerase chain reaction (PCR) method and cytogenetic studies were performed, in addition to histopathologic and immunophenotypic approaches in biopsied tissue from three patients with PCNS lymphoma. Immunosuppressive states and exposure to mutagens were not clear in all patients. RESULTS: Histopathologic examination disclosed a diffuse type of malignant lymphoma in all patients. Immunophenotypic studies revealed B cell phenotype in all patients, two of whom showed positive reaction for CD5. The PCR method revealed no involvement of EBV genome in tumors in any patients. The cytogenetic study showed clonal chromosome abnormalities in all patients, and abnormalities of chromosome 1 (1q21), 6 (-6, 6q15 and 6q21), 7 (-7 and 7p15), and 14 (14q24 and 14q32) were prominent. The t(6;14)(q15;q32) observed in Patient 1 is the first case to be reported in human de novo lymphoma. CONCLUSIONS: These findings indicate that the causative role of EBV in PCNS lymphoma without immune defects is not clear. The cytogenetic findings were similar to those observed in nodal B-cell lymphoma, suggesting that the origin of PCNS lymphoma cells does not differ from nodal B cell lymphoma cells cytogenetically.

Aged↗
PubMed1994

Extraocular muscle surgery in a rabbit model: site of reattachment following hang-back and conventional recession.

To determine the precise site of reattachment of recessed muscles, 4-mm conventional and hang-back recessions of the inferior rectus muscle were performed in 18 albino rabbits. Six weeks later, the distance from the anterior border of the reattached muscle to the insertion was measured both grossly and microscopically. In all cases the operated muscles had advanced minimally from the site of surgical placement. Gross observation showed that the mean forward creep was significantly greater for those rabbits which underwent hang-back recession (1.81 +/- 0.67 mm) than for those that were submitted to the conventional technique (0.83 +/- 0.38 mm). Measurements done on histological sections revealed that the mean distance of the anterior border of the muscle fiber from the reference suture was larger for conventional recession (2.73 +/- 0.75 mm) than for hang-back recession (1.91 +/- 0.72 mm).

Animals↗
PubMed1994

Immunohistochemical study of cellular fibronectin in preretinal membranes.

BACKGROUND: The presence of fibronectin has been shown in preretinal membranes from eyes with proliferative vitreoretinopathy and proliferative diabetic retinopathy. It is not clear, however, which type of fibronectin (plasma or cellular) is present in preretinal membranes. METHODS: A human cellular fibronectin antibody was used to immunohistochemically determine if cellular fibronectin only demonstrates presence or association with proliferation of preretinal membranes. RESULTS: The results revealed a diffuse distribution of cellular fibronectin within membranes extracted from proliferative vitreoretinopathy and proliferative diabetic retinopathy patients, and a localized distribution of neovascular vessels in proliferative diabetic retinopathy membranes. CONCLUSION: Cellular fibronectin produced locally in preretinal membranes may contribute a local, cell-mediated process to cell proliferation or migration and the expression of cellular fibronectin by the cellular constituents of preretinal membranes is unique to this pathologic situation like proliferative diabetic retinopathy and proliferative vitreoretinopathy.

Adult↗
PubMed1994

Cervical ripening and uterine contraction induced by prostaglandin E2-gel in pregnant Japanese monkeys (Macaca fuscata fuscata).

Effects of intracervical administration of PGE2-gel were studied in pregnant Japanese monkeys (Macaca fuscata fuscata) near term. Administration of PGE2-gel induced cervical ripening and an increase in maternal plasma PGE2 but no change in PGF2 alpha. Ultrastructural observations of the connective tissue of the cervix after PGE2-gel treatment revealed a decrease in the number of collagenous fibers. These results show that intracervical administration of PGE2-gel induces cervical ripening without induction of labor in the Japanese monkey.

Animals↗
PubMed1994

Renal pathology in patients with reflux nephropathy. The turning point in irreversible renal disease.

In reflux nephropathy both interstitial and glomerular damage advances with an increase in the scarring grade even in macroscopically normal regions. Based on various histologic findings, sclerosis and the enlargement of glomeruli rapidly accelerate between stages c-a and c-b, as shown by the combined Smellie's scarring grade of the bilateral kidneys. These two steep histologic changes in stage c-b are followed by a remarkable reduction in renal function (DTPA-GFR) and an increase in the amount of urinary protein. These clinicopathological changes thus suggest that hemodynamic changes or overloading in the functional remnant nephrons possibly start in stage c-a. It is also suggested that glomerular enlargement is an index of progressive disease in reflux nephropathy. Among our specimens, most cases of glomerular sclerosis were global while focal segmental glomerulosclerosis was very rare. These findings thus suggest that the global sclerosis observed in our specimens is clearly different from focal segmental glomerulosclerosis.

Adult↗
PubMed1994

Age-dependent decrease in platelet aggregation in rats.

The degree of platelet aggregation induced by ADP and collagen was examined in platelet-rich plasma from 7- to 90-week-old rats. The aggregation induced by ADP was unchanged at 90 weeks. Collagen-induced aggregation decreased remarkably at 60 and 90 weeks. Therefore, collagen-induced platelet activation is highly age-dependent, with rats of advanced age showing a lower response than younger rats.

Adenosine Diphosphate↗
PubMed1994

[Phimosis as a pathogenetic factor in urinary tract infection and vesicoureteral reflux].

The present study has been carried out to clarify relationship between phimosis and urinary tract infection or vesicoureteral reflux. The subjects consisted of 654 boys up to 15 years old with phimosis who had been treated at the outpatient division, Fukuoka University Hospital during 13 years from 1974; 393 boys (60%) with false phimosis, 261 boys (40%) with true phimosis. Thirty three cases (5%) had abnormal voiding (weak stream, preputial ballooning, dribbling etc.) Boys with true phimosis without abnormal voiding showed high incidence of urinary tract infection compared with normal subject, and if these boys had abnormal voiding symptoms as well, the incidence of urinary tract infection, particularly in the form of pyelonephritis, was noted to be high. Therefore, we suggest that boys with phimosis should be treated surgically. The incidence of urinary tract infection in boys with false phimosis were similar to normal group. All cases except one of vesicoureteral reflux accompanied by true phimosis was diagnosed as primary reflux cystoscopically. Therefore in most cases of phimosis associated with reflux, phimosis is determined to be only an accessory factor of vesicoureteral reflux. And refluxing patients should be worked up for urinary tract infection after they have had circumcision. Only in one boy with phimosis and reflux, was the reflux thought to be secondary reflux caused by phimotic obstruction.

Adolescent↗
PubMed1994

[Low molecular weight heparin inhibits raised intraocular pressure following intracameral administration of sodium hyaluronate].

The effect of low molecular weight (LMW) heparin on increase of intraocular pressure following intracameral administration of sodium hyaluronate (HA) was investigated in rabbit eyes. In each case, the aqueous humor of one eye was replaced with HA and a balanced salt solution (BSS) containing 10.0 IU/ml of LMW heparin, and as a control the aqueous humor of the fellow eye was replaced with HA and BSS containing no LMW heparin. Intraocular pressure was measured for 24 hours following the replacement. As a result, significant increase of intraocular pressure was observed at 6 hours after the injection in the eyes administered HA and BSS. In comparison, no significant increase of intraocular pressure was observed in the eyes injected with HA and LMW heparin. When the concentration of LMW heparin was less than 2 IU/nl or the LMW heparin was heat-deactivated, the HA-induced increase of intraocular pressure was not inhibited. The results indicated that LMW heparin inhibits increase of intraocular pressure following intracameral administration of HA possibly by an inhibitory effect on intraocular fibrin exudation, and the increase of intraocular pressure is probably associated with interaction between fibrin and HA.

Animals↗
PubMed1994

[Immunohistochemical localization of blood-retinal barrier breakdown after argon laser photocoagulation in the monkey retina].

Retinal photocoagulation induces breakdown of the blood-retinal barrier (BRB), but the site of the breakdown is not precisely known. The breakdown and repair of BRB following argon laser photocoagulation were studied in the monkey retina by immunohistochemical localization of serum albumin. Argon laser photocoagulation was performed to obtain ordinary burns as in human use. 1, 3, and 7 days after photocoagulation, serum albumin was observed in the outer retina and retinal pigment epithelium, but not around the retinal blood vessels. The immunostaining disappeared within 14 and 28 days after photocoagulation. The results of this study suggest that photocoagulation induces local breakdown of the outer BRB and that the breakdown is repaired within 14 days.

Animals↗
PubMed1992

Fine needle aspiration cytology of high grade T-cell lymphomas in human T-lymphotropic virus type 1 carriers.

We studied the fine needle aspiration (FNA) cytology of high grade peripheral T-cell lymphomas from eight human T-lymphotropic virus-1 (HTLV-1) positive patients. FNA smears from seven lymphomas showed a distinctive cytologic pattern with a dominance of rounded cells with irregular nuclei and a moderately basophilic cytoplasm. Irregular cells with a pale abundant cytoplasm were present in varying amounts. Some smears contained a few giant cells with cerebriform nuclei. In addition, plasma cells and eosinophils were found. Epithelioid cells were an inconstant finding. On histology these seven lymphomas were assigned to the pleomorphic medium-large cell subtype and all but one were of T-helper phenotype with rearrangements of the T-cell receptor. FNA smears from a lymph node in a patient with a previous histological diagnosis of lymphomatoid papulosis of the gingiva showed a monotonous pattern of large immunoblastic cells with some binucleated variants consistent with a diagnosis of high grade immunoblastic lymphoma, which was confirmed histologically. Our results show that peripheral T-cell lymphomas from HTLV-1 positive patients have cytological patterns which are distinctive enough to allow a conclusive diagnosis of high grade T-cell lymphoma. However, we do not think that the cytology of HTLV-1 positive lymphomas can be differentiated from that of virus-unrelated high grade T-cell lymphomas.

Adult↗
PubMed1992

Wolinella recta in adult gingivitis and periodontitis.

Wolinella recta has been associated with adult periodontitis, but its role in the disease remains uncertain. This report clarifies the distribution of W. recta in periodontally healthy and diseased subjects, and treated patients with recurrent disease. A specific polyclonal rabbit antiserum against W. recta strain 372 was used for indirect immunofluorescence localization of W. recta in dental plaque from untreated and treated patients. Supragingival plaque was collected from 15 periodontally healthy individuals (H), 10 adults with mild gingivitis (G1), 8 with severe gingivitis (G2) and 15 with periodontitis (AP). Subgingival samples from 23 diseased sites (G2 and AP) were examined as well. There was a significant difference (p = 0.000) between the proportions of W. recta in subgingival (4.4%) vs. supragingival (0.3%) plaque samples from AP. A significant difference (p = 0.000) in W. recta proportions was also detected between subgingival plaque samples of AP (4.4%) vs. G2 (1.2%). No significant difference in the mean % of W. recta was found between supragingival plaque of AP (0.3%) and G2 (0%), and samples of G1 (0.01%) and H (0.1%). In a separate study, 85 adults previously treated for moderate to severe adult periodontitis were monitored over a 12-month period for evidence of disease recurrence. Recurrent disease was detected at 32 sites in 18 subjects. Of these, 20 sites in 13 subjects were positive for W. recta. With subjects as the experimental unit, a significant increase in the proportions of W. recta was found at sites with recurrent disease (3.12%) as compared to stable, paired control sites (0.24%), but only when sites with breakdown and positive for W. recta were compared with their controls. These results indicate that W. recta is associated with some, but not all sites with advanced adult periodontitis. The association of W. recta with gingivitis was not statistically significant.

Adult↗
PubMed1992

Structural requirements of peptide YY for biological activity at enteric sites.

Peptide YY (PYY) is a colonic hormone consisting of 36 amino acids that is a potent inhibitor of pancreatic exocrine, gastric acid, and insulin secretion. The objective of the present experiments was to characterize the structural requirements of PYY for inhibition of pancreatic exocrine, gastric acid, and insulin secretion, using conscious dogs prepared with gastric and pancreatic fistulas. Intravenous administration of PYY-(1-36), PYY-(3-36), or PYY-(4-36) (400 pmol.kg-1 x h-1) inhibited cholecystokinin-8-stimulated (25 pmol.kg-1 x h-1) pancreatic exocrine secretion (P < 0.05); however, PYY-(1-10), PYY-(1-20), PYY-(6-36), PYY-(10-36), PYY-(13-36), PYY-(24-36), and PYY-(27-36) did not inhibit pancreatic exocrine secretion. Intravenous administration of PYY-(1-36), PYY-(3-36), or PYY-(4-36) (200, 400, 800 pmol.kg-1 x h-1) inhibited pentagastrin (0.5 microgram.kg-1 x h-1)-stimulated gastric acid secretion (P < 0.05), as well as 2-deoxy-D-glucose-stimulated insulin release (75 mg/kg) in a dose-related manner. PYY-(6-36), PYY-(13-36), and [Leu31, Pro34] neuropeptide Y did not inhibit either gastric acid secretion or insulin release. In the gastric acid and insulin secretion bioassays, PYY-(1-36) was significantly more potent than PYY-(3-36) and PYY-(4-36); however, in the pancreatic exocrine secretion bioassay, the inhibitory effects of PYY-(3-36) and PYY-(1-36) did not differ significantly. PYY-(4-36) was less potent than PYY-(1-36) on pancreatic exocrine secretion.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗