Biomedical subjects

K Tayama

Publications and source records attributed to K Tayama.

At least 37 records · Page 2Linked to original sources

PubMed2001

Antihypertensive effects of acetic acid and vinegar on spontaneously hypertensive rats.

To clarify the possibility of a preventive effect of dietary vinegar on blood pressure, long-term administration of vinegar or the acetic acid to SHR was examined. As a result, it was observed that acetic acid itself, the main component of vinegar, significantly reduced both blood pressure (p<0.05) and renin activity (p<0.01) compared to controls given no acetic acid or vinegar, as well as vinegar. There were no significant differences in angiotensin I-converting enzyme activity in various organs. As for the mechanism of this function, it was suggested that this reduction in blood pressure may be caused by the significant reduction in renin activity and the subsequent decrease in angiotensin II. From this study, it was also suggested that the antihypertensive effect of vinegar is mainly due to the acetic acid in it.

Acetic Acid↗

PubMed2001

The est1 regulation depends on the oxygen concentration in Acetobacter pasteurianus.

The regulation mechanism for expression of the ethanol inducible esterase gene, est1, was investigated in A. pasteurianus. Deletion analysis of the 5' non coding region of est1 showed that the FNR-binding consensus sequence is important in the induction of est1 by ethanol. Cells grown under oxygen starvation produced esterase-1 in not only the presence but also the absence of ethanol. These results suggest that the induction of est1-expression depends on the oxygen concentration, and the gene may be induced by a FNR-like factor activated by a decrease in the intracellular oxygen concentration.

Alcohol Dehydrogenase↗

PubMed2001

Xanthogranulomatous cholecystitis mimicking gallbladder cancer: report of a case.

A 61-year-old woman was admitted to our hospital with abnormal findings of abdominal computed tomography. Whereas she had neither fever nor abdominal pain, a cholecystitis was suspected. Ultrasonography showed a mass in the gallbladder with several stones, and an unclear border between the gallbladder and liver. Computed tomography showed a large-mass in the gallbladder with findings that seemed to indicate hepatic invasion and para-aortic lymph node metastasis. On the basis of these findings, we made a diagnosis of gallbladder cancer associated with hepatic invasion and lymph node metastasis. We treated this gallbladder tumor by hepatic arterial infusion chemotherapy via catheter with cisplatin and 5-fluorouracil. Four weeks after administration of the anti-cancer drugs, the tumorous lesion of the gallbladder could not be detected by abdominal imagings, and the gallbladder wall revealed no irregular findings. During laparotomy, the gallbladder showed signs of chronic cholecystitis, and a cholecystectomy was performed. Findings of the resected specimens showed severe inflammation, fibrosis, and bleeding in the gallbladder wall with infiltration by many foamy cells. Histopathological diagnosis was xanthogranulomatous cholecystitis. We report here a case of xanthogranulomatous cholecystitis mimicking gallbladder cancer and review the literature.

Cholecystitis↗

PubMed2001

Unruptured aneurysm of the right coronary sinus of Valsalva with type B aortic dissection.

A seventy-two year-old man, who complained of severe back pain, was referred to our hospital. Digital subtraction angiogram (DSA) delineated an extracardiac unruptured aneurysm of the right coronary sinus of Valsalva and acute type B aortic dissection. Patch plasty of the right coronary sinus with reimplantation of the right coronary artery using a Dacron graft was performed. Postoperative DSA confirmed successful reconstruction of the aortic root and the patent right coronary artery.

Aged↗

PubMed2000

Cerebral protection selection in aortic arch surgery for patients with preoperative complications of cerebrovascular disease.

OBJECTIVE: Retrograde perfusion is gaining acceptance as a means of cerebral protection, but it remains unclear how long the brain is protected and whether it is effective in patients with preoperative cerebrovascular disease. METHODS: From January 1989 to August 1999, 205 patients--118 male and 87 female patients who ranged 12 to 86 years old, mean: 65.5 years old--underwent surgery at our hospital for aortic arch aneurysm using cerebral protection. We focused on mortality, stroke incidence and perioperative risk factor between 2 groups--selective cerebral and retrograde cerebral perfusion--also studying patients with preoperative cerebrovascular disease that influenced postoperative stroke. RESULTS: The hospital mortality was 11.7% (selective cerebral perfusion group: 12%, retrograde group: 10.9%). Stroke occurred in 11 patients (5.3%), 4.7% in the selective cerebral perfusion group and 7.3% in the retrograde group. Preoperative cerebrovascular disease does not appear to be a risk factor for postoperative brain damage in aortic arch surgery. Regarding total replacement of the aortic arch, the incidence of postoperative brain damage in the retrograde group with preoperative cerebrovascular disease was higher than that in another group (p = 0.072). Cardiopulmonary bypass time and selective cerebral perfusion time in the patients with postoperative stroke were significantly longer than that in non-stroke group. CONCLUSIONS: Preoperative cerebrovascular disease did not appear to be a risk factor in postoperative neurological deficit in the selective cerebral perfusion group. Prolonged selective cerebral perfusion time and cardiopulmonary bypass time may, however, lead to brain edema and cause neurological deficit.

Adolescent↗

PubMed2000

Serum concentrations of advanced glycation endproducts are associated with the development of atherosclerosis as well as diabetic microangiopathy in patients with type 2 diabetes.

We measured serum concentrations of advanced glycation endproducts (AGEs) in patients with type 2 diabetes, to elucidate the mechanisms underlying the elevated serum concentrations of AGEs and to clarify the relationship between serum AGE concentrations and the development of microangiopathy and macroangiopathy. Serum AGEs were significantly higher in diabetic patients than in age-matched control subjects (p < 0.0001). In diabetic patients, serum AGEs were positively correlated with HbAlc (r = 0.47, p < 0.0001), urinary albumin excretion (UAE) (r = 0.42, p < 0.0001), diabetes duration (r = 0.31, p = 0.0030), and fasting plasma glucose (r = 0.34, p = 0.0010). Multiple regression analysis disclosed that only the HbAlc and UAE levels independently correlated with serum AGE levels. Serum AGEs in diabetic patients with progressive retinopathy and overt nephropathy were significantly higher than in those with less severe retinopathy and nephropathy. Serum AGEs were significantly higher in the diabetic patients with coronary heart disease (CHD) than in those without CHD. These results suggest that the HbAlc and UAE levels are independent risk factors for increased serum AGE concentrations in type 2 diabetic patients, and that higher serum AGE concentrations are associated with increased severity of diabetic retinopathy and nephropathy. Serum AGE concentrations may be a useful marker not only for the severity of diabetic microangiopathy but also for the development of CHD in patients with type 2 diabetes mellitus.

Aged↗

PubMed2000

An experimental study of atrial natriuretic peptide levels and the effect of inhaled nitric oxide after pneumonectomy.

The aim of this study was to investigate the changes in atrial natriuretic peptide (ANP) levels and lung cyclic guanosine 3',5'-monophosphate (cGMP) concentrations caused by pneumonectomy (Pn), and the effect of inhaled nitric oxide (NO) after Pn in a canine model. The mean pulmonary arterial pressure (PAP) and plasma ANP levels were measured over 180 min in two groups of dogs, one subjected to 60 min of 5 ppm NO inhalation (Pn + NO group, n = 5) and one subjected to 180 min without NO inhalation (Pn group, n = 5). The ANP and cGMP levels in the lung were also measured before and after Pn. Both the PAP and ANP levels increased significantly. Inhaled NO rapidly reduced the PAP and plasma ANP to levels similar to those before Pn. The lung ANP level was significantly increased after Pn, but inhaled NO reduced it to a level similar to that before Pn. The lung cGMP level, which was significantly decreased after Pn, was significantly increased by NO inhalation. These results indicate that NO administration may be effective for preventing post-Pn pulmonary hypertension, although an elevation in ANP does not reduce the PAP.

Animals↗

PubMed2000

Left ventricular myxoma: report of a case.

Although recent advances in echocardiography have made it easier to detect cardiac tumors, left ventricular myxomas are still rare and often not found until the patient presents with a history of syncopal episodes or systemic embolization. Left ventricular myxomas are usually benign and curable; however, unreliable excision of the myxoma due to poor visualization of the left ventricular cavity can result in recurrence. To prevent recurrence, it is necessary to select the most appropriate surgical approach to excise the myxoma completely. We report herein the case of a patient in whom surgical excision of a left ventricular myxoma arising from the posterior wall of the left ventricle was successfully performed.

Diagnosis, Differential↗

PubMed2000

Relationship between soluble thrombomodulin in plasma and coagulation or fibrinolysis in type 2 diabetes.

Serum concentration of soluble thrombomodulin (TM) is thought to be a marker for endothelial damage. Although several studies have reported that serum TM concentrations are increased in patients with diabetes mellitus, there is little information on the physiological function of soluble TM in human plasma. To evaluate the relationship of soluble TM in plasma between coagulation and/or fibrinolysis system in patients with diabetes, we measured plasma soluble TM, protein C activity (a natural anticoagulant induced by thrombin-TM complex), prothrombin F1+2 (a direct marker of thrombin generation), and plasmin-alpha 2-antiplasmin complex (PAP) and D dimer (measures of fibrinolytic activity) in 55 patients with type 2 diabetes mellitus. The plasma concentrations of soluble TM (P<0.01), protein C activity (P<0.01), prothrombin F1+2 (P<0.05), PAP (P<0.001) and D dimer (P<0.001) were significantly higher in the diabetic patients than the 48 age-matched control subjects. The plasma concentrations of TM and PAP were obviously increased in patients with diabetic nephropathy. In the diabetic patients, the plasma concentrations of soluble TM were inversely correlated with the protein C activity (r=-0.43, P<0.005), and were positively correlated with the plasma concentrations of prothrombin F1+2 (r=0.63, P<0.0001) and the plasma PAP concentrations (r=0.30, P<0.05). The present study demonstrated that both coagulation and fibrinolysis are enhanced concomitantly in patients with type 2 diabetes mellitus, and that an increase in plasma concentration of soluble TM is associated not only with hypercoagulability but also with enhanced fibrinolysis in diabetic patients.

Adult↗

PubMed2000

Serum levels of carboxy-terminal propeptide of human type I procollagen are an indicator for the progression of diabetic nephropathy in patients with type 2 diabetes mellitus.

The finding that glomerular mesangial cells produce human type I collagen suggests that the serum levels of carboxy-terminal propeptide of human type I procollagen (P1CP) may reflect the severity of diabetic nephropathy. We therefore investigated the relationship between serum P1CP levels and the extent of diabetic complications in 100 patients (46 males and 54 females) with Type 2 diabetes and in 64 healthy subjects. Serum P1CP was determined by radioimmunoassay. In diabetes, we defined P1CP levels less than 142 ng/ml as a normal P1CP group (group A), whereas we defined them as equal to or greater than 142 ng/ml as a high P1CP group (group B). The diabetic patients had significantly elevated serum P1CP levels compared with the controls. The prevalence of hypertension, proliferative diabetic retinopathy or macroalbuminuria was significantly higher in group B than in group A. Serum P1CP levels showed a significant positive correlation with urinary albumin excretion, but not with fasting blood glucose, glycosylated hemoglobin A(1c) or serum osteocalcin. Macroalbuminuric patients showed significantly higher P1CP levels than the normoalbuminuric patients. In patients in the absence of diabetic nephropathy, no significant differences of P1CP levels were found among the severity of diabetic retinopathy. The present results suggest that serum P1CP levels reflect the progression of diabetic nephropathy in patients with Type 2 diabetes.

Biomarkers↗

PubMed2000

A preoperative alternating chemotherapy and radiotherapy program for patients with stage IIIA (N2) non-small cell lung cancer.

The objective of the present study was to evaluate the feasibility and toxicity of a preoperative alternating chemotherapy and radiotherapy program followed by surgery in stage IIIA non-small cell lung cancer (NSCLC). The tumor response, resection rate, tumor/lymph node downstaging, and survival were also evaluated. The positive predictive value (PPV) in the diagnosis of mediastinal lymph node metastasis was 81% using conventional magnetic resonance imaging (MRI) with short inversion-time inversion recovery (STIR) technique (STIR-MRI) on our criteria. Eligible patients had clinical N2 lesions (stage IIIA) and a World Health Organization (WHO) performance status of 0-2. The treatment program consisted of two courses of preoperative cisplatin, vindesine, and ifosfamide; alternating with radiotherapy, including two courses of 20 Gy radiation. Surgery was performed within 4 weeks after the treatment. Twenty-two patients with stage IIIA (N2) NSCLC (20 men and two women, age 35-71 years) were enrolled into the study. Hematologic and other toxicities were within an acceptable range. Surgery was not indicated for two patients because of distant metastasis; one patient with renal dysfunction and one with pancytopenia during this treatment underwent surgery subsequently. The clinical response rate was 50% (partial response in 11/22). Definitive surgery was indicated for 18 patients resulting in 17 patients with complete resection and one exploratory thoracotomy. A pathologic complete response of the primary tumor occurred in 41% of the patients (seven of 17; without residual tumor), whereas 58% (ten of 17) were pathologic N0. The median survival was 33 months with an actuarial 4-year survival rate of 33% in 17 patients with complete resection and 30 months with 28% 4-year survival rate in all entered patients. A randomized phase-III study using this approach for stage IIIA (clinical N-2 disease) is warranted.

Adult↗

PubMed2000

Role of intracellular esterases in the production of esters by Acetobacter pasteurianus.

Esters are the major flavor compounds produced by Acetobacter sp. during vinegar production. The two genes encoding the esterases in the bacteria were disrupted, and the effects of the disruptions studied. When cultured in the presence of ethanol, the est1 gene-disrupted mutant (DE1K) did not produce any ethyl acetate or isoamyl acetate. However, the disruption of est2 did not affect the ester production. Ethyl acetate production by N-23 (pME122P) and DE1K (pME122P), which contain est1, was 1.7-fold higher than that by the wild type, N-23. On analyzing the relationship between ethyl acetate production and the extracellular ethanol and acetic acid concentrations, we found that the highest amount of ethyl acetate was produced when the molar ratio of ethanol and acetic acid was 1:1. These results indicate that the ester production by Acetobacter sp. is mostly catalyzed by the intracellular esterase, esterase-1, with ethanol and acetic acid used as the substrates.

Journal Article↗

PubMed2000

Surgical treatment for acute type A aortic dissection in pregnancy: a case of aortic root replacement just after Cesarean section.

A 25-year-old woman with Marfan syndrome in the 37th week of pregnancy was referred for acute chest pain and dyspnea. An emergency Cesarean section was performed because of fetal distress. Intraoperative echocardiography at the end of the Cesarean section showed dilatation of the aortic root and dissection of the ascending aorta. The patient underwent replacement of the aortic root and the ascending aorta on the following day because of uterine bleeding. The postoperative course was uneventful for the mother and her baby.

Adult↗

PubMed2000

Bilateral pleural effusion following cervical abscess drainage: a case report.

Postoperative bilateral chylothorax after cervical surgery has been rarely reported, whereas unilateral chylothorax has been occasionally reported after thoracic surgery. Here, we report a rare case of bilateral pleural effusion that developed after cervical abscess drainage. On the second day after the drainage, the patient felt dyspnea, and bilateral pleural effusion was found on a chest X-ray. The effusion was thought to be chyle and was successfully treated with conservative management. Additionally here, we have suggested that non-traumatic chylothorax was caused by increasing intraluminal pressure occurring inside the thoracic duct after its ligation. Careful follow up of any respiratory symptoms and of chest X-rays is recommended after cervical intervention.

Abscess↗

PubMed2000

Estrogen markedly increases LDL-receptor activity in hypercholesterolemic patients.

We investigated the change in low-density lipoprotein receptor activity following the administration of estrogen to patients with hypercholesterolemia (HC). Studies were conducted in 16 patients with HC (total cholesterol (TC)>220 mg/dL) and 133 healthy control subjects. LDL-R activity was measured by fluorocytometry. Three of sixteen patients with HC showed low LDL-R activity below 80% together with extremely high serum levels of TC and LDL cholesterol (LDL-C). LDL-R activity showed an inverse correlation with serum levels of TC and LDL-C (p<0.05, respectively). Two women with initially low LDL-R activity who showed a marked increase in LDL-R activity exhibited a normalized activity at four and eight weeks after estriol administration, proportional to the reduction in serum levels of TC and LDL-C. One man with an initially extremely low LDL-R activity showed no abnormality at the sites of exons 7, 14, 17 and intron 12 by the PCR-DGGE method, which are common sites for point-mutations of LDL-R among Japanese patients with HC. Estrogen reduced serum levels of TC and LDL-C in patients with HC, at least in part, via an increase in the LDL-R activity of patients with HC and an initially low LDL-R activity.

Adult↗

PubMed1999

Concentric wear of the Delrin disc in a Bjork-Shiley heart valve prosthesis: report of two cases.

We report herein the cases of two patients who received replacement of aortic Bjork-Shiley Delrin (BSD) valves that had been implanted for over 20 years following the development of aortic regurgitation (AR) resulting from wear of a Delrin disc. Case 1 was a 61-year-old woman in whom echocardiography revealed marked left ventricular dilatation and moderate AR 23 years after an aortic valve replacement (AVR) with a 21-mm BSD valve. Case 2 was a 51-year-old woman in whom echocardiography revealed marked dilation of the right atrium and moderate AR 23 years and 8 months after an AVR with a 21-mm BSD valve, as well as a mitral valve replacement with a 3M Starr-Edwards (SE) ball valve and tricuspid annuloplasty. In both patients, the BSD valves were replaced with other mechanical valves at reoperation. Examination of the explanted BSD valves showed that the Delrin discs contained increases in the radial gaps and strut indentation grooves on the inflow and outflow surfaces. The type and magnitude of the wear on the Delrin discs in these valves were consistent with data reported in the literature for this valve design after similar implant duration.

Aortic Valve↗

PubMed1999

Preperitoneal fat deposition estimated by ultrasonography in patients with non-insulin-dependent diabetes mellitus.

UNLABELLED: Preperitoneal fat is an indicator of visceral fat deposition, which is closely related to atherosclerosis and coronary heart disease in obese patients. We assessed the relationship of preperitoneal fat deposition and various clinical characteristics in 90 patients with non-insulin-dependent diabetes mellitus (NIDDM). Preperitoneal and subcutaneous fat deposition were measured by ultrasonography. In both the male and female diabetics, preperitoneal fat levels were significantly higher than in age-matched healthy subjects. We also determined blood pressures, fasting plasma glucose, glycosylated hemoglobin A1c, serum lipids, fasting immunoreactive insulin (FIRI), daily urinary C-peptide (CPR), serum leptin, urinary albumin excretion and body mass index (BMI). Of these parameters, BMI, FIRI, leptin and daily urinary CPR were positively correlated with preperitoneal fat deposition. Patients with diet therapy alone showed significantly higher preperitoneal fat levels than those receiving insulin therapy. In female, patients with increased preperitoneal fat showed higher prevalence of hypertension than those with decreased fat. Macroalbuminuric patients had a lower preperitoneal fat than microalbuminuric and normoalbuminuric patients. Patients with proliferative retinopathy exhibited lower preperitoneal fat than did those without retinopathy. Preperitoneal fat levels were positively correlated with motor or sensory nerve conduction velocity. CONCLUSION: The present findings suggest that in NIDDM patients, increased preperitoneal fat deposition is closely associated with obesity, hypertension and hyperinsulinemia, and negatively modulates diabetic microangiopathy including nephropathy, retinopathy and neuropathy.

Adipose Tissue↗

PubMed1999

Cloning and characterization of ethanol-regulated esterase genes in Acetobacter pasteurianus.

The esterase encoding genes, est1 and est2, were cloned from Acetobacter pasteurianus. Nucleotide sequence analysis of est1 revealed a gene of 954 bp, and est1 coded for an arylesterase with a molecular weight of 34863 Da consisting of 317 amino acids. The est2 gene contained an open reading frame composed of 1221 bp encoding an esterase with a molecular weight of 43389 Da consisting of 406 amino acids. The est1 gene showed some similarity, but the est2 gene showed no significant homology to other esterases reported in various microorganisms. Northern blot analysis of total RNA from A. pasteurianus revealed that transcription of the est1 gene was induced only when the cells were grown in a medium containing ethanol, and suggested that the est1 transcript is monocistronic. In contrast, transcription of the est2 gene was repressed in the presence of ethanol. In the absence of ethanol, expression of the est2-mRNA, capable of encoding a multiple number of proteins, was revealed by Northern blot analysis. In addition, deletion analysis indicated that the 5'-region of the est2 gene contained a cis-acting domain for est2 transcriptional regulation. Analysis of the est1 promoter using the chloramphenicol acetyltransferase gene as a reporter gene showed that the promoter within the 305-bp fragment upstream of the ATG initiation codon was responsible for the transcription in cells grown in the presence of ethanol. Primer extension analysis of est1-mRNA showed that the transcription initiation site was 49 bp upstream from the ATG initiation codon. The results of a gel mobility shift assay indicated that there is a regulatory protein related to est1 regulation, which may have some relation to the ethanol resistance of Acetobacter sp.

Journal Article↗