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H Hirakata

Publications and source records attributed to H Hirakata.

At least 55 records · Page 3Linked to original sources
PubMed1999

Propofol has both enhancing and suppressing effects on human platelet aggregation in vitro.

BACKGROUND: Volatile anesthetics are known to suppress platelet aggregation. In contrast, there is conflicting information regarding the effect of propofol on platelet function. The present study was designed to clarify the effects of propofol on platelet function and the mechanisms underlying these effects. METHODS: Propofol or an equivalent volume of 10% Intralipos (as a control) was added to test tubes 5 min before the induction of each reaction. Platelet aggregation induced by epinephrine, arachidonic acid (AA), prostaglandin G2 (PGG2), or STA2 (a thromboxane A2 [TXA2] analog) was measured using an eight-channel aggregometer. To determine type 1 cyclooxygenase activity, AA (0.5 mM) was added to an assay mixture containing type 1 cyclooxygenase, and the concentration of the final product, malonaldehyde, was measured by spectrophotometry. Epinephrine-, adenosine diphosphate-, AA-, and PGG2-induced TXA2 formation was measured using a commercially available radioimmunoassay kit. To estimate TXA2 receptor-binding affinity, 3H-S145, a specific TXA2 receptor antagonist, was added, and the radioactivity of receptor-bound 3H-S145 was determined using a liquid scintillation analyzer. Inositol 1,4,5-triphosphate formation was measured in STA2-stimulated platelets using a commercially available inositol 1,4,5-triphosphate assay kit. RESULTS: Propofol (40 microM) enhanced, whereas 100 microM suppressed, adenosine diphosphate- and epinephrine-induced secondary aggregation without affecting primary aggregation. Propofol (40 microM) also enhanced, but 100 microM suppressed, AA-induced aggregation. Propofol (100 microM) enhanced PGG2- and STA2-induced aggregation. Propofol (100 microM) suppressed AA-induced TXA2 formation but did not alter that induced by PGG2. Propofol (30-100 microM) suppressed AA-induced malonaldehyde formation, indicating inhibition of type 1 cyclooxygenase activity. Propofol did not alter TXA2 receptor-binding affinity. Propofol (30 and 100 microM) augmented inositol 1,4,5-triphosphate formation in STA2-stimulated platelets. CONCLUSIONS: The present findings clearly indicate that high concentrations of propofol suppress the activity of type 1 cyclooxygenase, the enzyme that converts AA to PGG2. Furthermore, propofol also enhanced STA2-induced inositol 1,4,5-triphosphate formation. These results may explain the inconsistent findings of previous investigators.

Adult↗
PubMed1999

[A case of systemic sclerosis with crescentic glomerulonephritis associated with perinuclear-antineutrophil cytoplasmic antibody (p-ANCA)].

A 50-year-old female with systemic sclerosis (SSc) developed rapidly progressive renal insufficiency. Laboratory findings showed rapid elevation of serum creatinine level (3.8 mg/dl) and a high titer of perinuclear-antineutrophil cytoplasmic antibody (p-ANCA) (504 EU/ml). Renal pathology revealed crescentic glomerulonephritis (CrGN) without mucoid intimal proliferation of the interlobal arteries and fibrinoid necrosis of the afferent arterioles, Immunofluorescent micrography showed focal segmental granular deposition of IgG and C 3 in the mesangium and along the capillary loop and was in agreement with pauci-immune type. Recently, a subtype of renal involvement in SSc that is associated exclusively with normotensive renal failure and recognizable by p-ANCA is suggested. On the other hand, SSc with p-ANCA-positive glomerulonephritis as this case can be considered to be overlap syndrome of SSc and microscopic polyangitis nodosa (microscopic PN) because in microscopic PN, p-ANCA is detected at the range of 50% to 80% and renal pathology reveals necrotizing glomerulonephritis. In this point, we may describe this case as a suggestive one about p-ANCA-positive glomerulonephritis.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed1999

[The effect of 5-HT 2 antagonist for urinary frequency symptom on diabetes mellitus patients].

17 cases of patients with diabetes mellitus who had urinary frequency symptom for which anti-cholinergic agents proved ineffective were given Sarpogrelate Hydrochloride (Anplag), a selective 5-HT 2 receptor antagonist. Efficacy was judged using IPSS and QOL scores after 2 weeks medications, these showed that all cases had improved their urinary frequency during the days as well as the night. This was especially true for the QOL score. One time urinary volume markedly increased, but there was no statistical significance after medication in maximum flow rate and residual urine. At the same time, a separate group of 14 mainly BPH cases did not improve entirely. It is believed that reaction in the detrusor muscle with hyperreflexia of diabetes mellitus patients can reach 5-HT, and its reaction is believed to reach via the 5-HT 2 receptor. This paper is a first clinical report of making use of 5-HT 2 antagonist as hyperactive detrusor on diabetes mellitus patients.

Adult↗
PubMed1999

[Immunohistochemical study of p53 and Ki-67 antigen expression in bladder carcinoma].

We examined the relationship between the expression of mutant p53 and Ki-67 antigens in urinary bladder transitional cell carcinoma and the pathological and clinical findings. Tissues were obtained from 28 patients with bladder carcinoma who underwent total or partial cystectomy. An ABC immunostaining method and two primary antibodies (DO-7 and MIB-1 antibodies) were used. The percentages of p53 and Ki-67 antigen-positive cells to the total number of cells were regarded as the p53 and Ki-67 labeling indices (LI) respectively. There were no statistically significant correlations between p53 LI and the histological grade or stage, although p53 LI increased slightly in the high grade and high stage group. There was a statistically significant correlation between Ki-67 LI and the histological grade and stage (p < 0.05). The correlation between p53 LI and Ki-67 LI was linear. Some cases had a p53 LI below the mean even though the Ki-67 LI was higher. The clinical course was characteristic of superficial bladder carcinoma initially, but progressed to invasive bladder carcinoma over the next several years. These results suggest that even cases initially diagnosed as superficial bladder carcinoma with a low p53 LI may progress to invasive bladder carcinoma in subsequent years. Therefore, it is important that the patient be followed-up.

Aged↗
PubMed1998

Disadvantage of long-term CAPD for preserving cardiac performance: an echocardiographic study.

The indices of cardiac performances were compared between 31 continuous ambulatory peritoneal dialysis (CAPD) and 20 long-term hemodialysis (HD) patients. They were subdivided into three groups according to dialysis duration: L-CAPD (n = 16, mean age and CAPD duration were, respectively, 53 +/- 8 [SD] years and 77 +/- 13 months); S-CAPD (n = 15; 52 +/- 12 years, 28 +/- 12 months); HD (n = 20; 51 +/- 10 years, 162 +/- 52 months). The diabetic HD patients (DM-HD; n = 13; 60 +/- 13 years of age, 22 +/- 11 months) were chosen separately. Thirteen normotensive subjects with normal kidney function (mean age, 57 +/- 9 years) were selected as an age-matched control group. There were no significant differences between groups in age, gender, incidence of original kidney disease, or serum biochemical data. The blood pressure and the cardiothoracic ratio in L-CAPD were highest among groups. The indices of left ventricular (LV) hypertrophy as well as LV performance by means of echocardiography or pulsed Doppler were compared. Among nondiabetic dialysis patients, the calculated LV mass index (LVMI) of 166.4 +/- 84.3 g/m2 and the ratio of the peak atrial filling velocity to the peak diastolic flow velocity of 1.25 +/- 0.4 in L-CAPD were greatest, and the left ventricular fractional shortening (%FS) of 34.2 +/- 10.8% in L-CAPD was smallest. LVMI or %FS of L-CAPD was the same as DM-HD of 161.0 +/- 40.7 g/m2 or 31.6 +/- 8.2%. Possibly, poor control of hypervolemia, which is caused by peritoneal problems induced by either peritonitis or chronic exposure to high-glucose dialysate, causes a substantial cardiac preload leading to incipient cardiac failure in L-CAPD. According to the similar results of L-CAPD and DM-HD, it may be that hypertension, hyperlipidemia, or long-term constant glucose loading of CAPD fluids in addition to impaired glucose tolerance by chronic renal failure is more or less related to the progression of LV hypertrophy and latent cardiac dysfunction in long-term CAPD patients. In this context, CAPD of more than 5 years' duration is disadvantageous for preserving cardiac function as compared with HD.

Adult↗
PubMed1998

Thiopental attenuates relaxation and cyclic GMP production in vascular smooth muscle of endotoxin-treated rat aorta, independent of nitric oxide production.

As thiopental (thiopentone) suppresses cyclic GMP (cGMP) formation produced by nitric oxide donor drugs, we have tested if it suppresses cGMP formation and increases vascular tone after induction of calcium-calmodulin-independent nitric oxide synthase (iNOS). Rat aortic rings were treated with Escherichia coli lipopolysaccharide (LPS) 1 microgram ml-1 for 4 h, and the effects of thiopental on tension, cGMP concentrations and nitrite accumulation were determined. Thiopental 0.3 mmol litre-1 reduced the tension of phenylephrine-precontracted aortic rings before LPS treatment, but caused no significant effects on tension in the presence of L-arginine 10 mumol litre-1 after LPS treatment. L-Arginine 1 mumol litre-1 to 1 mmol litre-1 increased concentrations of cGMP in LPS-treated aorta in a concentration-dependent manner. This was reduced by thiopental 0.3-1 mmol litre-1. Treatment with L-arginine 1 mmol litre-1 increased concentrations of nitrite, the end product of nitric oxide; this was not affected by thiopental 1 mmol litre-1. We conclude that thiopental suppressed cGMP formation in iNOS-induced vascular smooth muscle without affecting nitric oxide production.

Anesthetics, Intravenous↗
PubMed1998

Successful use of single-lumen, urokinase immobilized femoral catheters as a temporary access for haemodialysis.

METHODS: Placement of a femoral vein catheter as a temporary vascular access for haemodialysis was conducted and the indications, catheter patency rate, and incidence of catheter-related infections were examined. An urokinase immobilized femoral vein catheter (UIFC) is a soft polyurethane single-lumen catheter 2.7 mm in diameter and 22 cm in length which needs no heparin infusion (Japan Shawood Co., Ltd., Tokyo; Unitica Co., Ltd., Hyogo, Japan). A soft silicon rubber was attached to the tip of the catheter in order to avoid excessive bleeding during insertion. Aseptic adhesive wound dressing was employed at the exit-site which was cleansed with popidone-iodine and renewed at each dialysis session. RESULTS: Eighty-one UIFCs were used for haemodialysis in 64 patients (acute renal failure: 11; vascular access trouble: 53; initiation of chronic dialysis: 17). The average age of the patients was 58 +/- 13 years, ranging from 26 to 80 years. The mean duration of catheter indwelling was 22.4 +/- 13.1 days. An adequate blood flow of 180-200 ml/min was obtained through UIFC and returned to another peripheral vein punctured at each dialysis session. Unexplained fever occurred in four cases while the UIFC was in place (4.9%) but culture of either blood or the catheter tip was negative for bacteria. The catheter was removed immediately and fever subsided in all cases. The overall catheter survival rate was 84% at 34 days calculated using the Kaplan-Meier method. Catheter insertion was easy to perform and no serious complications such as pulmonary embolism or septicaemia occurred. CONCLUSION: Our modified type of UIFC is very useful as a temporary access for haemodialysis with a very low incidence of catheter-related infections and no need for heparinization. Excellent catheter patency was maintained with the plug system and careful dressing techniques without unnecessary bleeding during catheter care.

Adult↗
PubMed1998

Crescentic glomerulonephritis due to rifampin treatment in a patient with pulmonary atypical mycobacteriosis.

A 64-year-old male was treated continuously with rifampin, isoniazid and streptomycin for pulmonary atypical mycobacteriosis, Mycobacterium kansasii. Five weeks after beginning the treatment, the patient suddenly developed acute renal failure. A renal biopsy showed crescentic lesions characteristic of rapidly progressive glomerulonephritis with moderate interstitial changes. Serum antirifampin antibody was detected, and the cessation of rifampin treatment was followed by a rapid spontaneous recovery of the patient's renal function. This is, to our knowledge, the first case of rapidly progressive crescentic glomerulonephritis associated with rifampin treatment where circulating antirifampin antibody is demonstrated and the renal function spontaneously improved after discontinuing rifampin treatment.

Antibiotics, Antitubercular↗
PubMed1997

Platelet aggregation is impaired during anaesthesia with sevoflurane but not with isoflurane.

PURPOSE: Halothane suppresses platelet aggregation in vitro and ex vivo, and prolongs bleeding time. In a previous in vitro study we demonstrated that sevoflurane had a more suppressive effect on platelet aggregation than did halothane. The present study investigated whether the clinical use of sevoflurane affected platelet aggregation ex vivo. METHODS: Thirty-eight patients undergoing minor elective surgery were divided randomly into sevoflurane and isoflurane groups. Anaesthesia was induced with thiopentone i.v., and was maintained with sevoflurane or isoflurane with nitrous oxide. Blood was collected to measure platelet aggregation induced by adenosine diphosphate (ADP) and epinephrine. The first (control) blood collection was performed in the operating room before induction of anaesthesia, and the second 5-10 min after tracheal intubation but before the start of surgery, when the end-expiratory sevoflurane or isoflurane concentrations had stabilised at 1-1.5 times the minimum alveolar concentration (MAC) and mean arterial pressures were between 80-120% of preanaesthetic values. RESULTS: In all samples obtained during sevoflurane anaesthesia (n = 15), ADP and epinephrine could not induce secondary aggregation, although they did induce primary aggregation. In contrast, in the isoflurane group, both primary and secondary aggregation were observed in 14 out of 15 patients, and secondary aggregation was abolished in only one of the samples obtained during anaesthesia. CONCLUSIONS: Sevoflurane, but not isoflurane, alters platelet aggregation in the clinical situation, possibly by suppression of thromboxane A2 formation.

Adult↗
PubMed1997

Sudden death in chronic dialysis patients.

METHODS: Causes of sudden death were investigated in 113 chronic dialysis patients who died during the 10-year period from July 1979 to January 1989; postmortem examination was performed on 93 of the cases (autopsy rate; 82.3%). Sudden death was regarded as death 24 h after the onset of acute illness in patients without any restriction in their daily activities. There were 35 sudden death cases out of the 93 autopsied chronic dialysis patients. We analysed the causes of sudden death for all chronic dialysis patients and for those who died suddenly. RESULTS: The mean age of the 93 cases was 61.4 +/- 10.5 years (+/-SD). Stroke was the most frequent cause of death (24 cases, 25.8%) in the 93 autopsied cases. This was followed by cardiac disease in 18 (19.4%), infectious disease in 16 (17.2%), malignancy in 14 (15.1%), and dissecting aortic aneurysm in 5 (5.4%). The mean age of the 35 sudden death cases was 60.9 +/- 10.9 years. Of the 35 sudden death cases in chronic dialysis patients, dissecting aortic aneurysm was the most common cause of sudden death (5 cases, 14.3%), followed by cerebral haemorrhage in three (8.6%), acute subdural haematoma in three (8.6%), acute myocardial infarction in two (5.7%), cerebral infarction in two (5.7%), and subarachnoidal haemorrhage in one (2.9%). CONCLUSIONS: Dissecting aortic aneurysm, leading frequently to stroke as a cause of sudden death in chronic dialysis patients, at least in Japan, should be carefully differentiated from other cardiac diseases in chronic dialysis patients, such as severe atherosclerosis.

Adult↗
PubMed1997

Electron microscopic study of the penile plaques and adjacent corpora cavernosa in Peyronie's disease.

BACKGROUND: We conducted ultrastructural studies to clarify the fine structure of penile plaques and adjacent corpora cavernosa, and the causative basis for the process, in Peyronie's disease. METHODS: Penile plaques and adjacent corpora cavernosa were obtained during surgical extirpation from 5 patients with Peyronie's disease. Control tissues from the tunica albuginea and adjacent corpora cavernosa were obtained at penile amputation from 2 patients with penile cancer. Prepared tissues were examined by using electron microscopy. RESULTS: Penile plaques were composed of collagen fibrils, amorphous particulate material, and fibroblasts in all patients. In 1 of 5 patients, myofibroblasts were found in the border area between the lesion and underlying structures. Smooth-muscle cells and endothelial cells resembling myofibroblasts were noted in adjacent corpora cavernosa. In this patient, the plaque progressively enlarged, and was removed within 1 year of onset of the induration. CONCLUSIONS: Fibromatosis in Peyronie's disease involves both fibroblasts and myofibroblasts, which undergo sclerosis in some phase. In addition, smooth-muscle cells and endothelial cells in the adjacent corpora cavernosa may be incorporated in the fibromatosis.

Aged↗
PubMed1997

Risk factors for left ventricular hypertrophy in chronic hemodialysis patients.

Left ventricular hypertrophy is reported to be common in chronic hemodialysis patients, and also to increase the risk for mortality in chronic hemodialysis patients. An echocardiographical and clinical study was carried out to investigate the risk factors for left ventricular hypertrophy in 151 non-diabetic chronic hemodialysis patients without valvular diseases or myocardial infarction in two hemodialysis units in Fukuoka, Japan. The left ventricular mass index (LVMI) correlated positively to age, systolic blood pressure and interdialysis weight gain while it correlated negatively to the duration of hemodialysis therapy and hematocrit. Resorting to a multivariate analysis, the LVMI was found to positively correlate to age and the systolic blood pressure while it correlated negatively with the duration of hemodialysis therapy and the hematocrit level. These findings suggest that hypertension and anemia may thus be independent risk factors for left ventricular hypertrophy.

Cross-Sectional Studies↗
PubMed1997

[Uremic lung].

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Humans↗