Cytokine induction owing to LVAD support in canine models.
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to T Kanda.
Explore the source record for details and available documents.
The role of lymphocytes in the pathogenesis of viral myocarditis is controversial. To better understand how lymphocyte maturation controls a virus-induced myocarditic process, a murine model of viral myocarditis was utilized. Encephalomyocarditis virus (EMCV) was inoculated intraperitoneally into three kinds of mice; virus-susceptible C57BL/6, virus-resistant 129/SV and recombination activity gene (RAG)-2 knockout 129/SV mice. The RAG2 participate in the maturity of T and B lymphocytes. Survival rate, heart weight (HW), HW to body weight (BW) ratio, viral genome, cardiac inflammation and myocardial necrosis were evaluated after EMCV (500 plaque forming unit/mouse) inoculation. On post-inoculation day 10, the survival rate of C57BL/6, 129/SV and RAG2 knockout mice were 42, 90 and 0%, respectively. Myocardial viral titer was significantly (P<0.05) higher in C57BL/6 and RAG2 knockout mice than in 129/SV mice. In situ hybridization demonstrated the EMCV genome in the myocardium of RAG2 knockout and C57BL/6 mice, but not in 129/SV mice. At day 8, HW and HW/BW ratios were elevated (P<0.05) in RAG2 knockout mice as well as C57BL/6 mice compared with 129/SV mice. Myocardial necroses were more severe in RAG2 knockout mice than in wild-type 129/SV mice. In conclusion, matured lymphocytes protect the development of viral myocarditis which includes viral replication and myocardial apoptosis.
BACKGROUND/AIM: Patients with liver cirrhosis are insulin-resistant and frequently glucose-intolerant. Although peripheral glucose uptake has been shown to be impaired in liver cirrhosis, little is known about the significance of splanchnic (hepatic) glucose uptake after oral glucose load. METHODS/RESULTS: We performed an oral glucose tolerance test and euglycemic hyperinsulinemic clamp with oral glucose load for eight patients with liver cirrhosis and eight patients with chronic active hepatitis. The patients with liver cirrhosis had higher plasma glucose levels 2 h after glucose load than those with chronic active hepatitis (228+/-22 mg/dl vs. 102+/-9 mg/dl, p<0.01). Using the euglycemic hyperinsulinemic clamp with oral glucose load, we simultaneously measured peripheral and splanchnic glucose uptake. Peripheral glucose uptake in liver cirrhosis was 6.1+/-0.7 mg x kg(-1) x min(-1), which was lower than that in healthy volunteers (10.5+/-0.9 mg x kg(-1) x min(-1), p<0.05) and in chronic active hepatitis (8.4+/-0.3 mg x kg(-1) x min(-1), p<0.05). Furthermore, splanchnic glucose uptake in liver cirrhosis was much lower (20.1+/-3.4%) than in healthy volunteers (36.0+/-4.0%, p<0.05) and in chronic active hepatitis (37.2+/-3.1%, p<0.05). CONCLUSION: These results suggest that glucose intolerance in patients with liver cirrhosis is caused by a defect of the glucose uptake of both splanchnic and peripheral tissues.
Motoneurons need muscle-derived neurotrophic substances for their survival during the initial phase of their development, but after maturation they lose this requirement and can survive after axotomy. This suggests that some neurotrophic substances other than target-derived ones control the survival of motoneurons in adults. Because spinal motoneurons express fibroblast growth factor-9 (FGF-9) messenger RNA, we hypothesized that FGF-9 might be an autocrine or paracrine survival factor for motoneurons. FGF-9 promoted the survival of motoneurons and upregulated the choline acetyl-transferase (ChAT) activity in the dissociated cultures of ventral half of rat E13 spinal cord. Externally added FGF-9 was more effective in low density cultures, and polyclonal blocking antibody against FGF-9 significantly lowered the ChAT activity. Our results support an autocrine or paracrine role for FGF-9 in mediating the survival of spinal motoneurons. Non-target-derived neurotrophic substances for motoneurons including FGF-9 should be important in the pathogenesis of motor neuron disorders in the adults, especially amyotrophic lateral sclerosis.
Hormone replacement therapy (HRT) reduces the incidence of cardiovascular disease (CVD) in postmenopausal women (PMW). Recently, it has been reported that HRT declines angiotensin converting enzyme (ACE) activity, which may be one of the factors protecting against CVD. We measured the plasma levels of bradykinin, which would be expected to increase because the bradykinin-degrading enzyme (kinase II) is the same as ACE. Treatment with conjugated estrogens (0.625 mg/day) and medroxyprogesterone (2.5 mg/ day) was given for 3 months as HRT to 19 hypertensive and 19 normotensive PMW. Plasma bradykinin and ACE activity levels were measured at baseline and after 3 months of HRT. The plasma levels of ACE activity in both the hypertensive and normotensive PMW were significantly reduced by HRT. The plasma levels of bradykinin in the hypertensive PMW were significantly increased by HRT, whereas the administration of HRT tended to increase plasma levels of bradykinin in the normotensive PMW. The increased bradykinin levels with a concomitant decrease of plasma ACE activity by HRT in hypertensive PMW seem to be beneficial for reducing the risk of CVD.
A gene (named cell) homologous to the cellobiohydrolase I gene (cbhl) of Trichoderma reesei was isolated and sequenced from the white rot basidiomycete Irpex lacteus MC-2. The cell open reading frame consists of 1551 bp, which is interrupted by two introns, encoding a polypeptide of 517 amino acid residues with a calculated molecular mass of 54,522 Da. The deduced amino acid sequence showed that CEL1 (the protein encoded by cell) has a modular structure consisting of a catalytic domain of 449 amino acids and a C-terminal cellulose-binding domain (CBD) of 36 amino acids separated by a proline-, serine-, threonine-rich linker region of 32 amino acids. The CEL1 catalytic domain is homologous with fungal cellobiohydrolases (CBHs) belonging to family 7 of the glycosyl hydrolases. The transcription of cell was induced in the presence of various cellulosic substrates and repressed by glucose. It was therefore concluded that the reported sequence represents the first cellulase gene isolated from the basidiomycete Irpex.
A new exo-type cellulase, named exo-cellulase II (Ex-2), was purified from the crude enzyme preparation of Irpex lacteus. Ex-2 was very similar to the previously characterized exo-cellulase I (Ex-1) with respect to enzymatic features such as optimal pH, temperature, heat stability, and catalytic activity. However, Ex-2 exhibited greater pH stability than Ex-1. The molecular mass and carbohydrate content of Ex-2 (56,000, 4.0%) were different from those of Ex-1 (53,000, 2.0%). A cellulase gene (named cel2) encoding both Ex-2 and Ex-1 was isolated from an I. lacteus genomic library. The cel2 gene was found to consist of 1569 bp with an open reading frame encoding 523 amino acids, interrupted by two introns. The deduced amino acid sequences revealed that cel2 ORF has a modular structure consisting of a catalytic domain and a fungal-type cellulose-binding domain (CBD) separated by a serine-rich linker region. The catalytic domain was homologous to those of fungal cellobiohydrolases belonging to family 7 of the glycosyl hydrolases. Northern blot analysis showed that expression of the cel2 gene was induced by various cellulosic substrates and repressed by glucose, fructose, and lactose.
Anthocyanin pigments from rosé cider and red wine, which is a sparkling wine made from apples, were separated by gel permeation chromatography (GPC) using a TSK-GEL Toyopearl HW-40 (F) column with a 6:4 mixture of acetone and 8 M urea (pH 2.0) as the eluent. Under this condition, all phenolic compounds containing monomeric anthocyanins (mainly, cyanidin-3-galactoside; Cyn-3-gal), oligomeric and polymeric anthocyanins, chlorogenic acid, catechin, epicatechin, procyanidin B2 (PB2), and procyanidin C1 (PC1) in the apples and rosé cider were found to elute according to molecular weight. Bleaching of the anthocyanin pigments by SO(2) was gradually effective in the fractions separated by GPC according to elution volume. In the case of rosé cider, the levels of Cyn-3-gal decreased markedly during fermentation and then decreased gradually during maturation. We confirmed that anthocyanin polymers are not detectable in apple juice; these polymers are produced during fermentation and maturation as determined by GPC. The polymeric anthocyanins from red wine could be separated by this method, too.
OBJECTIVE: Conflicting results have emerged over the nature of autonomic nervous system abnormalities in human obesity. This present study was designed to investigate the sympatho-vagal activities and their responsiveness to acute cold exposure in age- and height-matched obese and non-obese young women. SUBJECTS: Twenty-four age- and height-matched obese (Weight: 68.1 +/- 2.64 kg, BMI: 26.3 +/- 0.74 kg/m2, %Fat: 39.9 +/- 1.23%) and non-obese young women (Weight: 46.9 +/- 0.77 kg, BMI: 18.5 +/- 0.18 kg/m2, %Fat: 22.9 +/- 0.8%). MEASUREMENTS: Plasma leptin, insulin, glucose and lipid concentrations were measured at rest. The sympathetic (SNS) and parasympathetic (PNS) nervous system activities were assessed by means of power spectral analysis of heart rate variability (HRV) for 15 min under control (25 degrees C) or acute cold exposure (10 degrees C) conditions. The very low (VLO) frequency component, and SNS (low/high power), and PNS (high/total power) indexes were used to evaluate thermoregulatory sympathetic function, and cardiac sympathetic and parasympathetic nervous activities, respectively. RESULTS: Plasma leptin concentration was significantly greater in the obese than in the control group (47.3 +/- 7.00 vs 12.1 +/- 1.22 ng.ml-1, P < 0.001). There was a highly positive correlation between plasma leptin concentration and percent of body fat (r = 0.863, P < 0.001). During the resting condition, there was no significant difference in any of the parameters of the HRV between the obese and control groups. Upon acute cold exposure, the VLO frequency component associated with thermoregulation (309 +/- 49.9 vs 578 +/- 142.2 ms2, P < 0.05) as well as its responsiveness (25-10 degrees C delta changes: 17 +/- 82.9 vs 326 +/- 138.2 ms2, P < 0.05) were significantly lower in the obese than in the control group. CONCLUSION: Our data indicate that a reduced autonomic, especially sympathetic responsiveness associated with thermoregulation and possibly leptin resistance might be aetiological factors of obesity in young women.
OBJECTIVE: To examine the influence of systemic nitric oxide (NO) synthesis on blood pressure in patients with chronic renal failure undergoing haemodialysis, since nitric oxides are susceptible to renal excretion or are dialysed, a different indicator that is unaffected by renal function, such as the level of exhaled NO was evaluated. We examined the levels of the endogenous NO before and after a haemodialysis session. DESIGN AND METHODS: We evaluated the serum concentrations of nitrite/nitrate and the rate of nitric oxide release into exhaled air in 10 patients with hypertension who were receiving maintenance haemodialysis. RESULTS: The serum concentrations of nitrite/nitrate before haemodialysis were significantly higher than those in 10 normal controls (183 +/- 151 microM vs 42 +/- 17 microM, P < 0.05). These levels decreased significantly by the end of haemodialysis (42 +/- 26 microM). Because the amount of nitric oxide in the deepest expirate correlated well with the duration of exhalation, we were able to derive the rate of release of NO. The rate of NO release was 0.034 +/- 0.012 nmol/sec before haemodialysis, similar to that in normal controls (0.031 +/- 0.013nmol/sec). The rate was significantly reduced after dialysis (0.023 +/- 0.010 nmol/sec) (P < 0.05). The mean pre-dialysis mean blood pressure (109 +/- 11 mm Hg) and the post-dialysis blood pressure (106 +/- 9 mm Hg) were the same. CONCLUSIONS: These data indicate that NO production does not appear to have a critical role in control of arterial blood pressure across haemodialysis in patients with chronic renal failure.
Lupus anticoagulant (LA) is an antibody that interferes with phospholipid-dependent coagulation tests. We investigated the usefulness of the ratio of factor V activity determined by the Simplastin auto test (PT assay) to factor V activity determined by the Platelin Excel LS test (APTT assay) for detection of LA in plasma samples obtained from 276 patients with haematological and non-haematological disorders and 73 healthy subjects. This ratio was significantly higher in the 15 LA-positive (4.82 +/- 3.34) than in samples from healthy subjects (1.09 +/- 0.10) and was > 1.4 in 10 of the remaining 261 patient samples. The ratio was particularly low in the 54 samples from warfarin-treated patients. These findings suggest that determination of this ratio may be useful as a routine laboratory test for detection of LA. This test requires no specific antigens and can be applied in patients receiving anticoagulants such as warfarin and heparin.
Budding yeast CDC45 encodes Cdc45p, an essential protein required to trigger initiation of DNA replication in late G1 phase. We cloned four and one species of the human Cdc45p homolog cDNA, resulting from different splicing patterns, from HeLa cell and human placenta cDNA libraries, respectively. A comparison of the cDNAs and the genomic sequence showed that the longest encoding a 610-amino acid protein was comprised of 20 exons. One species, which lacks exon 7 and contains the shorter of two exons 18, was identical with the previously reported CDC45L cDNA and constituted 24 out of 28 clones from HeLa cells. Splicing was different in HeLa cells and TIG-1 cells, a human diploid cell line. Human CDC45 protein was found to bind directly in vitro to human minichromosome maintenance 7 protein (hMCM7) and to the p70 subunit of DNA polymerase alpha. The data support a thesis that human CDC45 acts as a molecular tether to mediate loading of the DNA polymerase alpha on to the DNA replication complex through binding to hMCM7.
BACKGROUND: The TT virus (TTV), a new DNA virus found in Japan from a patient with post-transfusion hepatitis non-A-non-G, is frequently positive in the sera of patients with liver disease. It is not established whether this virus causes liver damage. We studied the frequency of superinfection of this virus and hepatitis C virus (HCV) known to be endemic among haemodialysis patients, and the possible deleterious effect of TTV on HCV-induced chronic liver disease. METHODS: We used primers from a conservative region in the TTV genome (Okamoto, 1998) to detect TTV. Sera from 163 dialysis patients positive for anti-HCV and 77 dialysis patients negative for anti-HCV (control) were tested. RESULTS: TT Virus positivity was 35% among HCV antibody (anti-HCV)-positive patients and 45.4% among anti-HCV-negative patients. TT Virus positivity was unrelated to the length of haemodialysis or amounts of blood the patients had received in the past. More anti-HCV-positive patients had a history of transfusion, but TTV positivity was not as closely associated with transfusion as anti-HCV positivity. The severity of chronic liver disease was estimated from peak serum alanine aminotransferase levels in the preceding 6 months. Among anti-HCV positives, TTV-positive patients tended to have less active disease; at least there was no indication that TTV superinfection aggravated chronic hepatitic C in long-term dialysis patients. Four of 35 anti-HCV-negative, TTV-positive patients had chronic active liver disease, while none of the anti-HCV-negative and TTV-negative patients did. CONCLUSIONS: TT Virus infection is prevalent among haemodialysis patients. Its transmission occurs not only by blood transfusion, but also by non-parenteral infection. Superinfection of TTV does not exert deleterious effects on the liver disease induced by HCV. However, it may cause chronic hepatitis in a limited number of patients, but remains dormant most of the time. Triple infection, HCV and TTV plus HBV or HGV (one case each), did not cause severe liver disease.
Serum concentrations of leptin, a hormone secreted into the circulation by adipocytes, correlate with body mass index. Circulating of leptin is thought to signal the brain in patients with hyperinsulinemia, a condition reported to be preventable and testable by exercise training. In the present experiments, sucrose-fed rats had reduced concentrations of leptin in portal venous blood after 4 weeks of nonforced wheel-running exercise (1.1 +/- 0.1 vs. 6.2 +/- 1.8 ng/mL, in nonexercised sucrose-fed rats, P < 0.05). Mesenteric and subcutaneous fat stores were similar between groups. After 12 weeks of exercise, portal vein levels of leptin concentrations (5.2 +/- 2.1 vs. 9.9 +/- 0.8 ng/mL, P < 0.05) and mesenteric and subcutaneous fat all were reduced in the exercise group. These results suggest that short-term running exercise reduces circulating leptin before any reduction of adipose mass, and this reduction in the concentration of leptin available to its receptors has beneficial effects on the metabolism of fat and carbohydrates.
UNLABELLED: The nucleus raphe magnus (NRM) is an important descending inhibitory system for pain transmission. We tested whether clonidine, an alpha2-adrenergic agonist, and yohimbine, an alpha2-adrenergic antagonist, modulate the activity of NRM neurons using extracellular recording in a rat brainstem slice preparation. Clonidine 1-20 microM increased firing frequencies (FF) in 22 (37%) and decreased FF in 6 (10%) spontaneously active neurons. Correlation between the concentrations of clonidine and FF changes was unremarkable. Eight spontaneously active neurons (13%) showed increases followed by decreases in FF with increasing doses of clonidine. The remaining 24 neurons (40%) showed no change in FF. Yohimbine 1 microM decreased FF in 38 spontaneously active neurons (58%), whereas the remaining 27 neurons (42%) showed no change in FF. In some neurons, yohimbine antagonized the increase or decrease in FF by application of clonidine. In three silent neurons (25%), clonidine (5 or 10 microM) induced firing activity, which stopped or decreased with the increasing doses of clonidine. In the remaining nine neurons (75%), clonidine did not induce firing activity. We conclude that activation and inhibition of alpha2-adrenergic receptors of NRM neurons augments and suppresses output of the descending inhibitory pain pathway. IMPLICATIONS: The nucleus raphe magnus is implicated in descending control of the nociceptive processes. We found that clonidine and yohimbine increased and decreased, respectively, the firing activity of a substantial number of nucleus raphe magnus neurons. Clonidine and may facilitate and yohimbine may reduce the outflow of the descending inhibitory pathway.
Studies of virus neutralization by antibody are a prerequisite for development of a prophylactic vaccine strategy against human papillomaviruses (HPVs). Using HPV16 and -6 pseudovirions capable of inducing beta-galactosidase in infected monkey COS-1 cells, we examined the neutralizing activity of mouse monoclonal antibodies (MAbs) that recognize surface epitopes in HPV16 minor capsid protein L2. Two MAbs binding to a synthetic peptide with the HPV16 L2 sequence of amino acids (aa) 108 to 120 were found to inhibit pseudoinfections with HPV16 as well as HPV6. Antisera raised by immunizing BALB/c mice with the synthetic peptide had a cross-neutralizing activity similar to that of the MAb. The data indicate that HPV16 and -6 have a common cross-neutralization epitope (located within aa 108 to 120 of L2 in HPV16), suggesting that this epitope may be shared by other genital HPVs.
Adeno-associated virus capsids are composed of three proteins, VP1, VP2, and VP3. Although VP1 is necessary for viral infection, it is not essential for capsid formation. The other capsid proteins, VP2 and VP3, are sufficient for capsid formation, but the functional roles of each protein are still not well understood. By analyzing a series of deletion mutants of VP2, we identified a region necessary for nuclear transfer of VP2 and found that the efficiency of nuclear localization of the capsid proteins and the efficiency of virus-like particle (VLP) formation correlated well. To confirm the importance of the nuclear localization of the capsid proteins, we fused the nuclear localization signal of simian virus 40 large T antigen to VP3 protein. We show that this fusion protein could form VLP, indicating that the VP2-specific region located on the N-terminal side of the protein is not structurally required. This finding suggests that VP3 has sufficient information for VLP formation and that VP2 is necessary only for nuclear transfer of the capsid proteins.
The prognosis for patients with idiopathic dilated cardiomyopathy (DCM) is poor, although clinical features are variable. Prediction of outcome has been difficult in individual patients based on laboratory data. In some patients with DCM, myocardial damage secondary to viral or immune-mediated myocardial inflammation may persist. To objectively assess inflammation, we measured plasma concentrations of C-reactive protein (CRP) in 188 patients with idiopathic DCM over 5-8 years. All had dyspnea and fatigue at rest; all patients had a left ventricular ejection fraction less than 40% by echocardiography or by contrast or radionuclide ventriculography. We divided these patients into two groups: patients dying within 5 years following admission (n = 49) and the remainder surviving for at least 5 years (n = 139). CRP concentrations in the patients dying early were significantly higher than in the long-term survivors (1. 05 +/- 1.37 vs. 0.49 +/- 1.04 mg/dl, p < 0.05). Sixty-two percent of the patients with CRP>1.0 died within 5 years. In addition to other laboratory tests including electrocardiography and echocardiography, routine CRP measurements proved to be valuable for identifying high-risk patients who require special treatment strategies.