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D Yamada

Publications and source records attributed to D Yamada.

27 records · Page 2Linked to original sources
PubMed1994

Direct evidence for erythropoietin-induced release of endothelin from peripheral vascular tissue.

The effect of recombinant human erythropoietin (r-HuEPO, 0.1 to 2.0 U/ml) on endothelin-1 (ET-1) release was examined in isolated hind legs perfused with Krebs-Ringer solution from normal rats. r-HuEPO increased immunoreactive (ir-) ET-1 release in a dose-dependent fashion; the maximal percent increment in ir-ET-1 release evoked by r-HuEPO (2.0 U/ml) was about +210% over the basal rate of release. However, r-HuEPO showed no effect on release of angiotensin II, thromboxane B2 or vasodilatory prostaglandin I2 from the vasculature. These results not only provide direct evidence that r-HuEPO has the potential to specifically stimulate release of ET-1 from peripheral vascular beds, but, hence, suggest a contributory role of ET-1 in r-HuEPO-induced hypertension in anemic human subjects undergoing r-HuEPO therapy.

6-Ketoprostaglandin F1 alpha↗
PubMed1990

[Clinico-bacteriological studies on the etiology of bacterial prostatitis. I. The distribution of clinical isolates and bacteria-specific immunoglobulin in EPS].

The distribution of clinical isolates from patients with prostatitis and pathogenicity of the isolates were studied. A new method for measuring the bacteria-specific immunoglobulins in expressed prostatic secretion (EPS) was developed and used for the detection of local immuno-reaction against pathogenic bacteria in the cases with prostatitis. There were no cases with increased antibodies specific for gram-positive cocci (GPC), indicating that the pathogenecity of GPC in bacterial prostatitis was doubtful. On the other hand, specific antibodies against gram negative rods (GNR) were elevated in all cases with acute prostatitis and changes of the antibody titers were correlated well to clinical courses. The present clinico-statistic and immuno-biological studies re-confirmed that E. coli was the main organism in uncomplicated bacterial prostatitis.

Adolescent↗
PubMed1990

[Clinico-bacteriological studies on the etiology of bacterial prostatitis. II. Virulence factors of E. coli in bacterial prostatitis].

The virulence factors of E. coli in bacterial prostatitis were studied using 59 E. coli isolated from uncomplicated prostatitis. O-antigens of prostatitis-derived E. coli belonged to some specific serotypes such as 0-4, 6, 18, 22 and the haemolysin production was positive in 64.4%. With regard to the fimbriae, the majority of the strains had type 1 fimbriae (81.4%). Mannose resistant (MR) fimbriae were also positive in 59.3% and both type 1 and MR fimbriae were positive in 55.9%. Among MR strains, P-fimbriated and S-fimbriated strains were present in 25.7% and 28.6%, respectively, indicating that these two MR fimbriae were not always specific for the prostatitis-derived E. coli. Although the specific adhesion of E. coli onto the human prostatic epithelium mediated by MR-fimbriae was equivocal, that mediated by type 1 fimbriae was observed clearly. Therefore, type 1 fimbriae was thought to be one of the most significant virulence factors in the pathogenesis of prostatitis caused by E. coli.

Bacterial Adhesion↗
PubMed1989

[Prostatic tissue and fluid levels of lomefloxacin (NY-198)].

The concentration of Lomefloxacin (NY-198), a new quinolone, in human prostatic tissue and fluid was examined. Lomefloxacin was concentrated in prostatic gland and the mean ratios of prostatic tissue levels to serum levels (P/S) were 1.39-1.83 during 2 to 6 hrs after administration. Concerning prostatic fluid concentrations, there were no significant differences between healthy volunteers and patients with chronic prostatitis. The mean ratios of prostatic fluid levels to serum levels (Pf/S) were 0.36-0.77 during 1 to 4 hrs after administration. The concentration of Lomefloxacin in the prostatic tissue and fluid is high enough to eradicate the majority of pathogens causing bacterial prostatitis.

4-Quinolones↗
PubMed1986

Hydrops fetalis secondary to Bart hemoglobinopathy.

Alpha-thalassemia is the most common cause of hydrops fetalis among Southeast Asians. With the recent influx of Southeast Asian refugees and the rapidly growing Filipino population this will become an increasingly important obstetric problem in the United States. Homozygous alpha-thalassemia, or Bart hemoglobinopathy, is invariably fatal to the fetus and produces significant maternal morbidity. Eighteen cases of homozygous alpha-thalassemia in one hospital are reviewed. This is the largest series reported in the United States. Recommendations are made for antenatal screening, diagnosis, and management of alpha-thalassemia.

Adult↗
PubMedDate not supplied

Plasma vascular endothelial growth factor in Japanese Type 2 diabetic patients with and without nephropathy.

AIM: To determine whether plasma vascular endothelial growth factor (VEGF) level is elevated in Type 2 diabetic patients with an early stage of diabetic nephropathy. METHODS: We studied 71 Japanese Type 2 diabetic patients with normal serum creatinine level (<100 micromol/l) (age 63.0 [60.3-65.6] years old, diabetes duration 15.6 [14.0-17.3] years, HbA1c 7.36% [7.06-7.66%], mean [95% confidence interval, CI]): normoalbuminuric patients (n=36); microalbuminuric patients (n=21); and proteinuric patients (n=14). Plasma VEGF concentration was measured by a quantitative sandwich enzyme immunoassay technique. RESULTS: Plasma VEGF concentration was not related to the degree of albuminuria: normoalbuminuric patients (25 [13-95] ng/l, median [25th-75th percentile]); microalbuminuric patients (33 [15-120] ng/l); and proteinuric patients (54 [17-107] ng/l). Plasma VEGF level in patients with retinopathy (25 [15-95] ng/l, n=30) was not elevated as compared to those without retinopathy (53 [14-126] ng/l, n=34). Plasma VEGF tended to correlated negatively with diabetes duration (R's=-.217, P=.0690) and HbA1c (R's=-.221, P=.0647), whereas there was no correlation between plasma VEGF level and age, serum creatinine or urinary albumin to creatinine ratio (ACR) of the patients, respectively. Plasma VEGF level in the group of patients with HbA1c equal to or below the median (<7.2%) was significantly higher than that in the group of patients with HbA1c above the median (>7.2%) (P<.05). CONCLUSIONS: The results suggested that Type 2 diabetic patients with microalbuminuria and those with retinopathy are not necessarily associated with an elevation of circulating plasma VEGF concentration. Plausible association between plasma VEGF level and glycemic control remains to be seen.

Aged↗
PubMedDate not supplied

[Clinical evaluation of basic fetoprotein in bladder cancer].

PURPOSE: The early diagnosis of bladder cancer allows for effective local treatment and optimizes the success of surgical therapy. Basic fetoprotein (BFP), measured using a rapid latex immuno-agglutination method, was introduced for the detection of transitional cell carcinoma. The objective of this study was to determine whether there was a correlation between urine BFP level and the grade or stage of bladder cancer, and whether the level could serve as a biochemical marker of bladder cancer. MATERIALS AND METHODS: Single voided specimens were obtained from 66 patients with confirmed or suspicious bladder cancer on cystoscopy, urine cytology or BFP. Each sample was divided into 3 aliquots of which 1 was for urine analysis, 1 was tested for BFP according to latex immunoagglutination method and 1 was sent for cytological examination. All patients subsequently underwent bladder biopsy. RESULTS: There were 54 (82%) patients with biopsy confirmed bladder cancer and 12 (18%) with benign conditions of the bladder. Overall sensitivity with BFP and urine cytology was 38.9% and 48.1% respectively. Specificity was 58.3% and 75.0%, and positive predictive value was 80.8% and 89.7%, respectively. The positive rate of BFP and cytology was higher in invasive cancer (75% and 100%, respectively) than in superficial cancer (36% and 28%). There was no correlation between BFP level and tumor grade, while cytology had a strong association. Linear regression analysis showed the significant correlation between BFP level and tumor size (r = 0.695, p < 0.0001). The detection rate of bladder cancer was higher by the combination of BFP and cytology than by using alone. CONCLUSIONS: BFP in conjunction with urine cytology can increase the detection rate of bladder cancer. But BFP alone cannot be used as a screening test for bladder cancer.

Adult↗