Biomedical subjects
T Otani
Publications and source records attributed to T Otani.
Changes in the structure of the myelinated nerve fiber with chemicals. V. Structural changes of the nerve fiber with mercuric chloride.
Explore the source record for details and available documents.
Differential platelet-associated factor gene expression by a panel of human cell lines with megakaryoblastic properties after treatment with phorbol myristate acetate.
Four human megakaryocytoid cell lines, namely MOLM-1, MOLM-7, MEG-01 and HEL, were treated with phorbol 12-myristate 13-acetate (PMA) and expression of the platelet-derived growth factor (PDGF) A chain, von Willebrand factor (vWF) and endothelial cell growth factor (ECGF) genes was examined by the reverse transcriptase-polymerase chain reaction (RT-PCR) using specific primers. The gene for PDGF A chain is constitutively weakly expressed by MEG-01 cells and strong expression is induced in MEG-01, MOLM-1 and MOLM-7 but not in HEL cells after treatment with PMA for three days. All four cell lines express the vWF gene both constitutively and after exposure to PMA. None of the cell lines constitutively express the gene for ECGF but MEG-01 cells can be induced to do so after treatment with the phorbol diester. Immunohistochemical staining after exposure to PMA showed that the expression of the platelet-associated markers CD41 and CD61 was enhanced in all cell lines indicating possible differentiation along the megakaryocyte lineage. Our results illustrate differential platelet-associated factor gene expression in different megakaryoblastic cell populations in response to treatment with PMA, and suggest that expressions of the PDGF A chain gene and the ECGF gene may be good markers for megakaryocyte maturation.
Age of onset and type of Japanese younger diabetics in Tokyo.
The age of onset of diabetes and the type of diabetes were examined in 1408 Japanese patients who were initially diagnosed as having diabetes under the age of 30 and were registered in our Diabetes Center between 1980 and 1989. Of the 1408 patients, 538 (38.2%) had insulin-dependent diabetes mellitus (IDDM) (male/female ratio of 2:3), and 870 (61.8%) had non-insulin-dependent diabetes mellitus (NIDDM) (male/female ratio of 5:4). There were significant differences of the sex ratio in both IDDM and NIDDM. The age at which the numbers in both the IDDM and NIDDM groups were almost equal was 13-14 (26 for IDDM and 23 for NIDDM at 13; 28 for IDDM and 30 for NIDDM at 14). A total of 58% of IDDM patients (22% of all patients) and only 6% of NIDDM patients (4% of all patients) were diagnosed under the age of 14 (P less than 0.01). Of the patients with IDDM, 42% (16% of all patients) were diagnosed over the age of 14, as were 94% of NIDDM (58% of all patients). The percentage of NIDDM cases increased even more over the age of 28, and no NIDDM patients developed diabetes under the age of 9.
Carotid atherosclerosis in young-aged IDDM associated with diabetic retinopathy and diastolic blood pressure.
To determine whether young patients with IDDM already have atherosclerosis and what factors would relate to atherosclerosis, we examined the intimal-medial thickness (IMT) of the common carotid artery by ultrasonography. Subjects were 29 young patients with IDDM (aged 17-39 years, duration 4-31 years) without manifest macroangiopathy and 13 healthy controls of comparable age (22-29 years). The carotid artery IMT of young patients with IDDM were significantly higher than those of controls (0.60 +/- 0.09 vs. 0.46 +/- 0.02 mm, P < 0.0001). The levels of IMT significantly correlated to diastolic blood pressure (r = 0.45, P < 0.02), and were higher in those with proliferative retinopathy than those without retinopathy (0.66 +/- 0.09 vs. 0.55 +/- 0.08 mm, P < 0.02). The levels of IMT showed no significant correlation to the attained age, duration of IDDM, HbA1c, systolic blood pressure, and cholesterol level. These findings suggest the usefulness of this examination for the early detection of diabetic macroangiopathy, and point to a close relationship between microangiopathy and macroangiopathy in IDDM.
Changes of albumin concentrations in the first morning urine according to age and sex in 2990 healthy children and adults.
This study was performed to clarify the changes in urinary albumin excretion according to age and sex in healthy subjects, for the appropriate judgment of microalbuminuria in insulin-dependent diabetes mellitus (IDDM). Concentrations of albumin in the first morning urine from 2990 healthy individuals (1713 males, 1277 females) aged from 6 to 39 years were measured by turbidimetry immunoassay. Reference values of the concentrations for each age group were obtained from the 95% confidence limits from the distribution simulated by the chi 2-test (k = 1). Reference values were 1.3-2.2 mg/dl in children aged 6-11 years. Values for females increased significantly from 22 mg/dl at age 11 years to 3.9 mg/dl at age 12 years (P < 0.0001) and those of males increased gradually from 1.7 mg/dl at age 11 years to 3.9 mg/dl at age 16 years. There were significant differences between males and females at the ages of 12 (P < 0.0001), 13 (P < 0.0001), and 14 (P < 0.0007). After 17 years, the values decreased from 3.9 mg/dl to 3.3 mg/dl in females, and to 2.9 mg/dl in males. We conclude that reference values of urinary albumin excretion change according to age and sex, which should be taken into consideration in the assessment of diabetic nephropathy in IDDM.
Development of diabetic nephropathy in Japanese patients with insulin-dependent diabetes mellitus: Tokyo Women's Medical College epidemiologic study.
To clarify the development of diabetic nephropathy in Japanese insulin-dependent diabetes mellitus (IDDM), 373 patients with IDDM who had no proteinuria at the first visit to our Diabetes Center were evaluated. The incidence of persistent proteinuria increased rapidly between 10 and 19 years of diabetes duration, and only a few new cases occurred thereafter. Patients whose ages at onset of IDDM were 9-17 years (n = 167) and 18-29 years (n = 90) had rapid development of persistent proteinuria compared to the 0 to 8-year group (n = 116) (p < 0.02 and p < 0.003, respectively). Females (n = 233) developed persistent proteinuria to a greater extent until 24 years of diabetes duration than males (n = 140) (p = 0.17). Development of proteinuria did not vary according to calendar year of diagnosis of IDDM or diabetes duration at the first visit. Renal insufficiency (serum creatinine of 2.0 mg/dL or greater) followed the onset of proteinuria; 60% of the patients with the onset of IDDM between 1951 and 1969 developed renal insufficiency 10 years after the onset of proteinuria, whereas 30% of patients with the onset of IDDM after 1970 developed this condition. Development of renal insufficiency did not vary according to sex, age at onset of IDDM, or age at onset of proteinuria. Renal failure requiring dialysis therapy occurred within 4 years after renal insufficiency. In conclusion, development of diabetic nephropathy in Japanese IDDM exhibits three stages. The onset of proteinuria appears to be influenced by age at onset of IDDM and sex.(ABSTRACT TRUNCATED AT 250 WORDS)
Slightly elevated blood pressure as well as poor metabolic control are risk factors for the progression of retinopathy in early-onset Japanese Type 2 diabetes.
Not a few patients in Japan with early-onset type 2 (non-insulin-dependent) diabetes become blind due to proliferative diabetic retinopathy (PDR). However, the risk factors are poorly understood. The aim of this study was to determine the risk factors for background diabetic retinopathy (BDR) and PDR by following 394 Japanese patients with early-onset type 2 diabetes diagnosed before 30 years of age (mean age 27, mean blood pressure at entry 116/73 mm Hg). Of the 322 patients who were free of diabetic retinopathy at entry, 88 developed BDR, giving an incidence of 57.7 (95% CI 55.5-60. 0)/1000 person-years. Cox proportional hazard analysis revealed mean HbA(1c) and duration of diabetes to be significant predictors of development of BDR. Of the 160 patients with BDR, i.e., the 72 patients who had BDR at entry and the 88 who developed BDR during the follow-up, 50 developed PDR, giving an incidence of 17.9 (95% CI 13.6-23.6)/1000 person-years. Cox proportional hazard analysis indicated mean HbA(1c) and diastolic blood pressure to be significant predictors of the progression from BDR to PDR. In conclusion, in early-onset Japanese type 2 diabetic patients, the rates of both development of BDR and of progression from BDR to PDR appear to be potentially high. Not only lifetime exposure to glycemia but also a slightly elevated blood pressure level is an important risk factor for progression to PDR.
Therapeutic effect of oral levofloxacin, ciprofloxacin, and ampicillin on experimental murine pneumonia caused by penicillin intermediate Streptococcus pneumoniae for which the minimum inhibitory concentrations of the quinolones are similar.
The therapeutic efficacy of oral treatment with levofloxacin, ciprofloxacin, and ampicillin on an experimental pneumonia caused by the penicillin-intermediate Streptococcus pneumoniae for which the minimum inhibitory concentrations (MICs) of the quinolones are similar was assessed in immunocompetent CBA/J mice. Levofloxacin exhibited a dose-dependent therapeutic effect, and achieved complete eradication of S. pneumoniae from the lungs at 120 mg/kg/day, whereas ciprofloxacin and ampicillin were hardly effective at all. A pharmacokinetic study in infected mice revealed good oral absorption and lung tissue penetration of levofloxacin (peak lung concentration: 5.95 microg/g of lung), low oral absorption of ciprofloxacin in spite of a good penetration into lung tissue (1.10 microg/g of lung), and low lung tissue penetration of ampicillin despite rather good oral absorption (1.71 microg/g of lung). In an in vitro time-kill study that simulated the peak concentration of drugs in the lungs of infected animals, the killing activity of levofloxacin was found to be greater than that of ciprofloxacin and ampicillin. These data suggest that the therapeutic efficacy of levofloxacin in this model is attributable to both its potent bactericidal activity and excellent pharmacokinetic profile.
Usefulness of diagnostic criteria for aspiration cytology of hepatocellular carcinoma.
OBJECTIVE: To establish new criteria for cytodiagnosis of hepatocellular carcinoma by comparing cytologic findings of hepatocellular carcinoma with those of liver cirrhosis. STUDY DESIGN: Review of cytologic findings of hepatocellular carcinoma on preoperative aspiration biopsy of 31 lesions from 27 patients who underwent surgical resection and comparison of these findings with those of liver cirrhosis in 17 patients. RESULTS: In the 11 lesions of moderately and poorly differentiated hepatocellular carcinoma, significant cytologic findings included monotonous and abundant cytoplasm, thick cytoplasm, increased nuclear/cytoplasmic ratio, irregular nuclear contours, increased chromatin density, intranuclear vacuoles and naked nuclei. In the 20 lesions demonstrating well-differentiated hepatocellular carcinoma, significant cytologic findings included monotonous and scant cytoplasm, well-defined cytoplasmic borders, thick cytoplasm, eccentric nuclei, increased nuclear/cytoplasmic ratio, thick nuclear membranes and increased chromatin density. We established the criteria for moderately and poorly differentiated hepatocellular carcinoma as including three cytologic parameters: increased nuclear/cytoplasmic ratio, irregular nuclear contours and increased chromatin density. We also established the criteria for well-differentiated hepatocellular carcinoma as including six cytologic parameters: monotonous cytoplasm, scant cytoplasm, well-defined cytoplasmic borders, thick cytoplasm, eccentric nuclei and increased nuclear/cytoplasmic ratio. For all 31 hepatocellular carcinoma lesions, including 27 lesions that were < or = 2 cm in diameter, both sensitivity and specificity were 100% by concurrently employing both criteria. CONCLUSION: The new criteria for cytodiagnosis we established were useful for differentiating hepatocellular carcinoma from liver cirrhosis. In particular, our criteria ensured appropriate diagnostic accuracy for well-differentiated hepatocellular carcinoma.
Clear demonstration of carcinoma of the ampulla of Vater with ultrasonography.
We present a non-icteric case, in which an ampullary polypoid lesion was clearly demonstrated by ultrasonography, suggesting carcinoma of the ampulla of Vater. The lesion was a 3 cm in diameter, spherical tumor with a polypoid surface, and internal hyperechogenicity. The patient underwent a curative pylorus-preserving pancreaticoduodenectomy.