956 resultados para nonstructural protein 5
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Introduction: A resorbable collagen matrix with recombinant human bone morphogenetic protein (rhBMP-2) was compared with traditional iliac crest bone graft for the closure of alveolar defects during secondary dental eruption. Methods: Sixteen patients with unilateral cleft lip and palate, aged 8 to 12 years, were selected and randomly assigned to group 1 (rhBMP-2) or group 2 (iliac crest bone graft). Computed tomography was performed to assess both groups preoperatively and at months 6 and 12 postoperatively. Bone height and defect volume were calculated through Osirix Dicom Viewer (Pixmeo, Apple Inc.). Overall morbidity was recorded. Results: Preoperative and follow-up examinations revealed progressive alveolar bone union in all patients. For group 1, final completion of the defect with a 65.0% mean bone height was detected 12 months postoperatively. For group 2, final completion of the defect with an 83.8% mean bone height was detected 6 months postoperatively. Dental eruption routinely occurred in both groups. Clinical complications included significant swelling in three group 1 patients (37.5%) and significant donor-site pain in seven group 2 patients (87.5%). Conclusions: For this select group of patients with immature skeleton, rhBMP-2 therapy resulted in satisfactory bone healing and reduced morbidity compared with traditional iliac crest bone grafting.
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Extraction of intracellular protein from Escherichia coli is traditionally achieved by mechanical disruption. A chemical treatment that destroys the integrity of the bacterial cell wall and could provide an alternative technique is examined in this study. Treatment with a combination of the chelating agent ethylenediaminetetraacetate (EDTA) (greater than 0.3 mM) and the chaotropic agent urea (6 M) is highly effective at releasing protein from uninduced E. coli. The 6 M urea in the presence of 3 mM EDTA can release cytoplasmic protein from both logarithmic-phase and stationary-phase E. coli cells at levels equivalent to mechanical disruption. The concentrations of the two chemical agents were the major variables affecting the maximum levels of protein release. Several minor variables and interactions were also identified. The kinetics of protein release is first order. For 2, 4, and 6 M urea with 3 mM EDTA, the time constant is approximately 2.5 min independent of urea concentration. Kinetics for 3 mM EDTA without urea is considerably slower, with a time constant of 12.3 min. (C) 1997 John Wiley & Sons, Inc.
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We analyzed the effect of a 6-week aerobic exercise training program on the in vivo macrophage reverse cholesterol transport (RCT) in human cholesteryl ester transfer protein (CETP) transgenic (CETP-tg) mice. Male CETP-tg mice were randomly assigned to a sedentary group or a carefully supervised exercise training group (treadmill 15 m/min, 30 min sessions, five sessions per week). The levels of plasma lipids were determined by enzymatic methods, and the lipoprotein profile was determined by fast protein liquid chromatography (FPLC). CETP activity was determined by measuring the transfer rate of (14)C-cholesterol from HDL to apo-B containing lipoproteins, using plasma from CETP-tg mice as a source of CETP. The reverse cholesterol transport was determined in vivo by measuring the [(3)H]-cholesterol recovery in plasma and feces (24 and 48 h) and in the liver (48 h) following a peritoneal injection of [(3)H]-cholesterol labeled J774-macrophages into both sedentary and exercise trained mice. The protein levels of liver receptors were determined by immunoblot, and the mRNA levels for liver enzymes were measured using RT-PCR. Exercise training did not significantly affect the levels of plasma lipids or CETP activity. The HDL fraction assessed by FPLC was higher in exercise-trained compared to sedentary mice. In comparison to the sedentary group, a greater recovery of [(3)H]-cholesterol from the injected macrophages was found in the plasma, liver and feces of exercise-trained animals. The latter occurred even with a reduction in the liver CYP7A1 mRNA level in exercised trained animals. Exercise training increased the liver LDL receptor and ABCA-1 protein levels, although the SR-BI protein content was unchanged. The RCT benefit in CETP-tg mice elicited by exercise training helps to elucidate the role of exercise in the prevention of atherosclerosis in humans.
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Mice expressing human cholesteryl ester transfer protein (huCETP) are more resistant to Escherichia coli bacterial wall LIPS because death rates 5 days after intraperitoneal inoculation of LIPS were higher in wild-type than in huCETP(+/-) mice, whereas all huCETP(+/+) mice remained alive. After LIPS inoculation, plasma concentrations of TNF-alpha and IL-6 increased less in huCETP(+/+) than in wild-type mice. LPS in vitro elicited lower TNF-alpha production by CETP expressing than by wild-type macrophages. In addition, TNF-alpha production by RAW 264.7 murine macrophages increased on incubation with LPS but decreased in a dose-dependent manner when human CETP was added to the medium. Human CETP in vitro enhanced the LIPS binding to plasma high-density lipoprotein/low-density lipoprotein. The liver uptake of intravenous infused C-14-LPS from Salmonella typhimurium was greater in huCETP(+/+) than in wild-type mice. Present data indicate for the first time that CETP is an endogenous component involved in the first line of defense against an exacerbated production of proinflammatory mediators.
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Ninety-one consecutive systemic lupus erythematosus (SLE) patients (American College of Rheumatology criteria) with a history of cutaneous vasculitis were compared to 163 SLE controls without this clinical manifestation from July to December 2007 in order to determine the possible clinical and serological association of this manifestation. Data were obtained in an ongoing electronic database protocol and autoantibodies to anti-double-stranded DNA, anti-Sm, anti-RNP, anti-Ro/SS-A, anti-La/SS-B, and anticardiolipin and ribosomal P protein antibody (anti-P) were detected by standard techniques. Exclusion criteria were the presence of anti-phospholipid syndrome or antibodies, Sjogren syndrome, and a history of thrombosis. The mean age (38.5 +/- 11.5 vs. 37.8 +/- 11.6 years, p = 0.635), disease duration (12.5 +/- 7.8 vs. 11.8 +/- 7.9 years, p = 0.501), and frequency of white race (71.4% vs. 70.5%, p = 0.872) and female sex (96.8% vs. 93.7%, p = 0.272) were comparable in both groups. The vasculitis group had a higher frequency of malar rash (97.9% vs. 87.4%, p = 0.004), photosensitivity (91.4% vs. 81.6%, p = 0.030), and Raynaud phenomenon (RP; 27.7% vs. 7.5%, p < 0.001), whereas all other clinical manifestation including renal and central nervous system involvements were similar to the control group. Laboratorial data revealed that only anti-P (35.1% vs. 12.1%, p < 0.001) was more frequent in patients with vasculitis. In a multivariate logistic regression model, cutaneous vasculitis was associated to the presence of RP (OR = 3.70; 95% confidence interval [CI] = 1.73-8.00) and anti-P (OR = 3.42; 95% CI = 1.76-6.66). In summary, SLE cutaneous vasculitis characterizes a subgroup of patients with more RP and anti-P antibodies but not accompanied by a higher frequency of renal and central nervous system involvements.
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Paracoccidioides brasiliensis yeast cells can enter mammalian cells and may manipulate the host cell environment to favour their own growth and survival. Moreover, fibronectin and several other host extracellular matrix proteins are recognized by various components of the yeast cell extracts. The present study was designed to isolate and characterize a fibronectin-binding protein from P. brasiliensis. We also compared P. brasiliensis strain 18, tested before (Pb18a) and after (Pb18b) animal passage, in relation to its adhesion and invasion processes. Extracts from both samples, when cultured on blood agar solid medium, showed higher levels of protein expression than when the same samples were cultured on Fava-Netto solid medium, as demonstrated by two-dimensional electrophoresis and SDS-PAGE. Also, both Pb18a and Pb18b exhibited stronger adhesion to A549 epithelial cells when cultured on blood agar medium than when cultured on Fava-Netto medium. Ligand affinity binding assays revealed a protein of 54 kDa and pl 5.6 in P. brasiliensis cell-free extracts with the properties of a fibronectin-binding adhesin, which was characterized by tryptic digestion and mass spectroscopy as a homologue of enolase from P. brasiliensis. Antibody raised against this 54 kDa protein abolished 80 % of P. brasiliensis adhesion to A549 epithelial cells. Our results demonstrate that P. brasiliensis produces a fibronectin-binding adhesin, irrespective of the culture medium, and that this activity can be inhibited by a specific antibody and is involved in the adhesion of the fungus to pulmonary epithelial cells.
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Low-grade inflammation adversely influences metabolism and cardiovascular prognosis, nevertheless increased intake of fruits and vegetables has rarely been studied in this context. Objective: In a prospective controlled study, the effect on C-reactive protein (CRP) levels was assessed. Methodology: Sixty consecutive women undergoing cosmetic abdominal surgery were instructed to consume six servings each of fruits and vegetables during the first postoperative month. Detailed 24h interviewer-administered dietary recall was conducted at baseline and at the end of the study, with weekly returns to monitor unscheduled dietary changes and compliance with the protocol. Variance (ANOVA) and covariance (ANCOVA) were evaluated to confirm significance and minimize confounding variables. Results: No differences concerning age (42.2 +/- 5.3 vs 41.1 +/- 6.0 years) or BMI (25.5 +/- 3.1 vs 25.0 +/- 3.0 kg/m(2)) occurred. Ingestion of fruits increased to approximately 5.2 vs 3.9 and of vegetables 5.9 vs 3.4 servings/ day, respectively. CRP decreased more conspicuously in the treated group (P = 0.028), and correlation between vitamin C input and CRP in supplemented participants was demonstrated (P = 0.014). Conclusions: Higher intake of antioxidant foods was feasible, and an antiinflammaotory effect occurred. Further studies with longer administration and follow-up period are recommended.
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Our data suggest that serum concentrations of insulin-like growth factor I and insulin-like growth factor binding protein 3 do not correlate with breast cancer development. (Fertil Steril (R) 2011;95:2753-5. (C)2011 by American Society for Reproductive Medicine.)
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Introduction: The delay in the diagnosis of infections can be deleterious in renal transplant recipients. Thus, laboratory tests leading to an earlier diagnosis are very useful for these patients. Purpose: To assess the behavior of C-reactive protein (CRP) in renal transplant recipients with a diagnosis of cytomegalovirus (CMV) infection, tuberculosis (TB) and bacterial infection (BI). Methods: A retrospective analysis of 129 patients admitted at our hospital, from 2006 to 2008 because of CMV, TB or BI, was carried out. Appropriate statistical analysis was done and values were expressed as medians, range. Results: When CRP levels were compared among the groups with CMV disease, TB or BI, the group with CMV disease presented lower levels of CRP (18.4 mg/L, 0.28-44 mg/L) than the TB and BI (p < 0.05) groups. The area under the receiver-operating characteristics curve, distinguishing CMV disease from TB/BI, was 0.96 (p < 0.0001), resulting in 100% sensitivity and 90.63% specificity to detect CMV disease when CRP < 44.5 mg/L. The subgroup analysis of CMV infection showed increasing levels of CRP (0.28, 16 and 29.5 mg/L) in the asymptomatic, symptomatic and invasive disease subgroups, respectively (p < 0.05). Conclusion: The measurement of CRP levels may be a useful tool for differentiating CMV infection from the other types (bacterial or TB) of infection in kidney transplant recipients.
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Mechanisms regulating NADPH oxidase remain open and include the redox chaperone protein disulfide isomerase (PDI). Here, we further investigated PDI effects on vascular NADPH oxidase. VSMC transfected with wild-type PDI (wt-PDI) OF PDI mutated in all four redox cysteines (mut-PDI) enhanced (2.5-fold) basal cellular ROS production and membrane NADPH oxidase activity, with 3-fold increase in Nox1, but not Nox4 mRNA. However, further ROS production, NADPH oxidase activity and Nox1 mRNA increase triggered by angiotensin-II (AngII) were totally lost with PDI overexpression, suggesting preemptive Nox1 activation in such cells. PDI overexpression increased Nox4 mRNA after AngII stimulus, although without parallel ROS increase. We also show that Nox inhibition by the nitric oxide donor GSNO is independent of PDI. PDI silencing decreased specifically Nox1 mRNA and protein, confirming that PDI may regulate Nox1 at transcriptional level in VSMC. Such data further strengthen the role of PDI as novel NADPH oxidase regulator. (C) 2009 Elsevier Inc. All rights reserved.
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Although it is well known that catecholamines inhibit skeletal muscle protein degradation, the molecular underlying mechanism remains unclear. This study was undertaken to investigate the role of beta(2)-adrenoceptors (AR) and cAMP in regulating the ubiquitin-proteasome system (UPS) in skeletal muscle. We report that increased levels of cAMP in isolated muscles, promoted by the cAMP phosphodiesterase inhibitor isobutyl methylxanthine was accompanied by decreased activity of the UPS, levels of ubiquitin-protein conjugates, and expression of atrogin-1, a key ubiquitin-protein ligase involved in muscle atrophy. In cultured myotubes, atrogin-1 induction after dexamethasone treatment was completely prevented by isobutyl methylxanthine. Furthermore, administration of clenbuterol, a selective beta(2)-agonist, to mice increased muscle cAMP levels and suppressed the fasting-induced expression of atrogin-1 and MuRF-1, atrogin-1 mRNA being much more responsive to clenbuterol. Moreover, clenbuterol increased the phosphorylation of muscle Akt and Foxo3a in fasted rats. Similar responses were observed in muscles exposed to dibutyryl-cAMP. The stimulatory effect of clenbuterol on cAMP and Akt was abolished in muscles from beta(2)-AR knockout mice. The suppressive effect of beta(2)-agonist on atrogin-1 was not mediated by PGC-1 alpha (peroxisome proliferator-activated receptor-gamma coactivator 1 alpha known to be induced by beta(2)-agonists and previously shown to inhibit atrogin-1 expression), because food-deprived PGC-1 alpha knockout mice were still sensitive to clenbuterol. These findings suggest that the cAMP increase induced by stimulation of beta(2)-AR in skeletal muscles from fasted mice is possibly the mechanism by which catecholamines suppress atrogin-1 and the UPS, this effect being mediated via phosphorylation of Akt and thus inactivation of Foxo3. (Endocrinology 150: 5395-5404, 2009)
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This study investigated the in vivo effects of the Bothrops Jararaca venom (BjV) on general metabolic profile and, specifically. oil muscle protein metabolism in rats. The crude venom (0.4 mg/kg body weight, IV) was infused in awake rats, and plasma activity of enzymes and metabolites levels were determined after 1, 2, 3, and 4 hours. BjV increased urea, lactate, and activities of creatine kinase. lactate dehydrogenase. and aspartate aminotransferase after 4 hours. The content of liver glycogen was reduced by BjV. Protein metabolism was evaluated by means of microdialysis technique and in isolated muscles. BjV induced increase in the muscle interstitial-arterial tyrosine concentration difference. indicating a high protein catabolism. The myotoxicity induced by this venom is associated with reduction of protein synthesis and increase in rates of overall proteolysis, which was accompanied by activation of lysosomal and ubiquitin-proteasome systems without changes in protein levels of cathepsins and ubiquitin-protein conjugates.
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The present work investigated the role of the sympathetic nervous system (SINS) in the control of protein degradation in skeletal muscles from rats with streptozotocin (STZ)-induced diabetes. Diabetes (1, 3, and 5 days after STZ) induced a significant increase in the norepinephrine content of soleus and EDL muscles, but it did not affect plasma catecholamine levels. Chemical sympathectomy induced by guanethidine (100 mg/kg body weight, for 1 or 2 days) reduced muscle norepinephrine content to negligible levels (less than 5%), decreased plasma epinephrine concentration, and further increased the high rate of protein degradation in muscles from acutely diabetic rats. The rise in the rate of proteolysis (nmol.mg wet wt(-1).2h(-1)) in soleus from 1-day diabetic sympathectomized rats was associated with increased activities of lysosomal (0.127 +/- 0.008 vs. 0.086 +/- 0.013 in diabetic control) and ubiquitin (Ub)-proteasome-dependent proteolytic pathways (0.154 +/- 0,007 vs. 0.121 +/- 0.006 in diabetic control). Increases in Ca2+-depenclent (0.180 +/- 0.007 vs. 0.121 +/- 0.011 in diabetic control) and Ub-proteasome-dependent proteolytic systems (0.092 +/- 0.003 vs. 0.060 +/- 0.002 in diabetic control) were observed in EDL from 1-day diabetic sympathectomized rats. The lower phosphorylation levels of AKT and Foxo3a in EDL muscles from 3-day diabetic rats were further decreased by sympathectomy. The data suggest that the SNS exerts acute inhibitory control of skeletal muscle proteolysis during the early stages of diabetes in rats, probably involving the AKT/Foxo signaling pathway.
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It has been demonstrated that glutamine, a conditionally essential amino acid, improves nitrogen balance, acts as a stimulant of protein synthesis, and decreases proteolysis in myopathic children. In contrast, other studies have shown no beneficial effect of glutamine supplementation on burn victims or critically ill patients. Nonetheless, we hypothesized that glutamine supplementation would increase the fractional protein synthesis rate (FSR) in the jejunal mucosa of malnourished male Wistar rats. Thus, the objective of the present study was to test the effect of daily oral glutamine supplementation (0.42 g kg(-1) d(-1) for 14 days) on the FSR of the jejunal mucosa of healthy and malnourished rats. A 4-hour kinetic study with L-[1-(13)C]leucine was subsequently performed, and jejunal biopsies were obtained 1.5 cm from the Treitz angle and analyzed. Malnourished rats showed a 25% weight loss and increased urinary nitrogen excretion. Plasma amino acid concentration did not differ between groups. (13)C enrichment in plasma and jejunal cells was higher in the malnourished groups than in the healthy group. The FSR (percent per hour) was similar for the control and experimental groups (P > .05), with a mean range of 220%/h to 27%/h. Oral glutamine supplementation alone did not induce higher protein incorporation by the jejunal mucosa in malnourished rats, regardless of total food intake or the presence or absence of glutamine supplementation. (C) 2009 Elsevier Inc. All rights reserved.
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The effects of 2 diets with different protein contents on weight loss and subsequent maintenance was assessed in obese cats. The control group [Cc; n = 8; body condition score (BCS) = 8.6 +/- 0.2] received a diet containing 21.4 g crude protein (CP)/MJ of metabolizable energy and the high-protein group (HP; n = 7; BCS = 8.6 +/- 0.2) received a diet containing 28.4 g CP/MJ until the cats achieved a 20% controlled weight loss (0.92 +/- 0.2%/wk). After the weight loss, the cats were all fed a diet containing 28.0 g CP/MJ at an amount sufficient to maintain a constant body weight (MAIN) for 120 d. During weight loss, there was a reduction of lean mass in Cc (P < 0.01) but not in HIP cats and a reduction in leptinemia in both groups (P < 0.01). Energy intake per kilogram of metabolic weight (kg(-0.40)) to maintain the same rate of weight loss was lower (P < 0.04) in the Co (344 +/- 15.9 kJ.kg(-0.40).d(-1)) than in the HP group (377 +/- 12.4 kJ.kg-(0.40).d(-1)). During the first 40 d of MAIN, the energy requirement for weight maintenance was 398.7 +/- 9.7 kJ.kg(-0.40).d(-1) for both groups, corresponding to 73% of the NRC recommendation. The required energy gradually increased in both groups (P < 0.05) but at a faster rate in HP; therefore, the energy consumption during the last 40 d of the MAIN was higher (P < 0.001) for the HP cats (533.8 +/- 7.4 kJ.kg(-0.40).d(-1)) than for the control cats (462.3 +/- 9.6 kJ.kg(-0.40).d(-1)). These findings suggest that HIP diets allow a higher energy intake to weight loss in cats, reducing the intensity of energy restriction. Protein intake also seemed to have long-term effects so that weight maintenance required more energy after weight loss. J. Nutr, 139: 855-860, 2009.