984 resultados para calcium response


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DNA-hsp65, a DNA vaccine encoding the 65-kDa heat-shock protein of Mycobacterium leprae (Hsp65) is capable of inducing the reduction of established tumors in mouse models. We conducted a phase I clinical trial of DNA-hsp65 in patients with advanced head and neck carcinoma. In this article, we report on the vaccine`s potential to induce immune responses to Hsp65 and to its human homologue, Hsp60, in these patients. Twenty-one patients with unresectable squamous cell carcinoma of the head and neck received three doses of 150, 400 or 600 mu g naked DNA-hsp65 plasmid by ultrasound-guided intratumoral injection. Vaccination did not increase levels of circulating anti-hsp65 IgG or IgM antibody, or lead to detectable Hsp65-specific cell proliferation or interferon-gamma (IFN-gamma) production by blood mononuclear cells. Frequency of antigen-induced IL-10-producing cells increased after vaccination in 4 of 13 patients analyzed. Five patients showed disease stability or regression following immunization; however, we were unable to detect significant differences between these patients and those with disease progression using these parameters. There was also no increase in antibody or IFN-gamma responses to human Hsp60 in these patients. Our results suggest that although DNA-hsp65 was able to induce some degree of immunostimulation with no evidence of pathological autoimmunity, we were unable to differentiate between patients with different clinical outcomes based on the parameters measured. Future studies should focus on characterizing more reliable correlations between immune response parameters and clinical outcome that may be used as predictors of vaccine success in immunosuppressed individuals. Cancer Gene Therapy (2009) 16, 598-608; doi:10.1038/cgt.2009.9; published online 6 February 2009

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Background. The ability to inhibit inappropriate or unwanted actions is a key element of executive control. The existence OF executive function deficits in schizophrenia is consistent with frontal lobe theories of the disorder. Relatively few Studies have examined response inhibition in schizophrenia, and none in adolescent patients with early-onset schizophrenia (EOS). Methods. Twenty-one adolescents with (lie onset of clinically impairing psychosis before 19 years of age and 16 matched controls performed a stop-signal task to assess response inhibition. The patients with EOS were categorized Lis paranoid (n= 10) and Undifferentiated subtypes (n= 11). The undifferentiated group had higher levels of negative symptomatology. Stop-signal reaction time (SSRT) and go-signal reaction time (Go-RT) were analysed with respect to hand of response. Results. The Undifferentiated early-onset patients had significantly longer SSRTs, indicative of poor response inhibition, for the left hand compared to the paranoid early-onset patients and control participants. No differences existed for inhibitory control with the right hand. The three groups did not differ in Go-RT. Conclusions. Our results indicate a specific lateralized impairment of response inhibition in patients With Undifferentiated, but not paranoid, EOS. These findings are consistent with reports of immature frontostriatal networks in EOS and implicate areas such as the pre-motor cortex and Supplementary motor area (SMA) that are thought to play a role in both voluntary initiation and inhibition of movement.

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We sought to evaluate this ""response-to-injury"" hypothesis of atherosclerosis by studying the interaction between systolic blood pressure (SBP) and LDL-cholesterol (LDL-C) in predicting the presence of coronary artery calcification (CAC) in asymptomatic men. We Studied 526 men (46 +/- 7 years of age) referred for electron-beam tomography (EBT) exam. The prevalence of CAC was determined across LDL-C tertiles (low: <115 mg/dl; middle: 115-139 mg/dl high: >= 140 mg/dl) within tertiles of SBP (low: <121 mmHg; middle: 121-130 mmHg; high: >= 131 mmHg). CAC was found in 220 (42%) men. There was no linear trend in the presence of CAC across LDL-C tertiles in the low (p = 0.6 for trend) and middle (p = 0.3 for trend) SBP tertile groups, respectively. In contrast, there was a significant trend for increasing CAC with increasing LDL-C (1st: 44%; 2nd: 49%; 3rd: 83%; p < 0.0001 for trend) in the high SBP tertile group. In multivariate logistic analyses (adjusting for age, smoking, triglyceride levels, HDL-cholesterol levels, body mass index, and fasting glucose levels), the odds ratio for any CAC associated with increasing LDL-C was significantly higher in those with highest SBP levels, whereas no such relationship was observed among men with SBP in the lower two tertiles. An interaction term (LDL-C x SBP) incorporated in the multivariate analyses was statistically significant (p = 0.038). The finding of an interaction between SBP and LDL-C relation to CAC in asymptomatic men support the response-to-injury model of atherogenesis. (C) 2007 Elsevier Ireland Ltd. All rights reserved.

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Matricellular proteins play a unique role in the skeleton as regulators of bone remodeling, and the matricellular protein osteonectin (SPARC, BM-40) is the most abundant non-collagenous protein in bone In. the absence of osteonectin, mice develop progressive low turnover osteopenia, particularly affecting trabecular bone. Polymorphisms in a regulatory region of the osteonectin gene are associated with bone mass in a subset of idiopathic osteoporosis patients, and these polymorphisms likely regulate osteonectin expression. Thus it is important to determine how osteonectin gene dosage affects skeletal function. Moreover, intermittent administration of parathyroid hormone (PTH) (1-34) is the only anabolic therapy approved for the treatment of osteoporosis, and it is critical to understand how modulators of bone remodeling, such as osteonectin, affect skeletal response to anabolic agents. In this study, 10 week old female wild type, osteonectin-haploinsufficient, and osteonectin-null mice (C57Bl/6 genetic background) were given 80 mu g/kg body weight/day PTH(1-34) for 4 weeks. Osteonectin gene dosage had a profound effect on bone microarchitecture. The connectivity density of trabecular bone in osteonectin-haploinsufficient mice was substantially decreased compared with that of wild type mice, suggesting compromised mechanical properties. Whereas mice of each genotype had a similar osteoblastic response to PTH treatment, the osteoclastic response was accentuated in osteonectin-haploinsufficient and osteonectin-null mice. Eroded surface and osteoclast number were significantly higher in PTH-treated osteonectin-null mice, as was endosteal area. In vitro studies confirmed that PTH induced the formation of more osteoclast-like cells in marrow from osteonectin-null mice compared with wild type. PTH treated osteonectin-null bone marrow cells expressed more RANKL mRNA compared with wild type. However, the ratio of RANKL:OPG mRNA was somewhat lower in PTH treated osteonectin-null cultures. Increased expression of RANKL in response to PTH could contribute to the accentuated osteoclastic response in osteonectin(-/-) mice, but other mechanisms are also likely to be involved. The molecular mechanisms by which PTH elicits bone anabolic vs. bone catabolic effects remain poorly understood. Our results imply that osteonectin levels may play a role in modulating the balance of bone formation and resorption in response to PTH. (c) 2008 Elsevier Inc. All rights reserved.

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Objective: GH secretagogues (GHS) produce exaggerated ACTH and cortisol responses in Cushing`s disease (CD) patients, attributable to their direct action on GH-releasing peptide receptor type la (GHSR-1a). However, there are no studies correlating the ill vivo response to GHS and GHSR-1a mRNA expression in ACTH-dependent Cushing`s syndrome (CS) patients. The aim of this study is to correlate the patterns of ACTH and cortisol response to GH-releasing peptide-6 (GHRP-6) to GHSR-1a expression in ACTH-dependent CS patients Design: Prospective study in a tertiary referral hospital center. Fifteen CD patients and two ectopic ACTH syndrome (EAS) patients were studied. Methods: Tumor fragments were submitted to RNA extraction, and GHSR-1a expression was studied through real-time qPCR and compared with normal tissue samples. The patients were also submitted to desmopressin test and vasopressin receptor type 1B (AVPR1B) mRNA analysis by qPCR. Results: GHSR-1a expression was similar in normal pituitary samples and in corticotrophic tumor samples. GHSR-1a expression was higher in patients (CD and EAS) presenting ill vivo response to GHRP-6. Higher expression of AVPR1B was observed in the EAS patients responsive to desmopressin, as well as in corticotrophic tumors, as compared with normal pituitary samples, but no correlation between AVPR1B expression and response to desmopressin was observed in the CD patients. Conclusions: Our results revealed a higher expression of GHSR-1a in the ACTH-dependent CS patients responsive to GHRP-6, suggesting an association between receptor gene expression and ill vivo response to the secretagogue in both the CD and the EAS patients.

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Hepatitis C virus (HCV) is a major cause of hepatic disease and of liver transplantation worldwide. Mannan-binding lectin (MBL), encoded by the MBL2 gene, can have an important role as an opsonin and complement activating molecule in HCV persistence and liver injury. We assessed the MBL2 polymorphism in 102 Euro-Brazilian patients with moderate and severe chronic hepatitis C, paired for gender and age with 102 HCV seronegative healthy individuals. Six common single nucleotide polymorphisms in the MBL2 gene, three in the promoter (H/L, X/Y and P/Q) and three in exon 1 (A, the wild-type, and B, C or D also known as O) were evaluated using real-time polymerase chain reaction with fluorescent hybridization probes. The concentration of MBL in plasma was measured by enzyme-linked immunosorbent assay. The frequency of the YA/YO genotype was significantly higher in the HCV patients compared with the controls (P = 0.022). On the other hand, the genotypes associated with low levels of MBL (XA/XA, XA/YO and YO/YO) were decreased significantly in the patients with severe fibrosis (stage F4), when compared with the patients with moderate fibrosis (stage F2) (P = 0.04) and to the control group (P = 0.011). Furthermore, MBL2 genotypes containing X or O mutations were found to be associated with non-responsiveness to pginterferon and ribavirin treatment (P = 0.023). MBL2 polymorphisms may therefore be associated not only with the development of chronic hepatitis C, but also with its clinical evolution and response to treatment.

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Small mammals are subject to predation from mammalian, avian and reptilian predators. There is an obvious advantage for prey species to detect the presence of predators in their environment, enabling them to make decisions about movement and foraging behaviour based on perceived risk of predation. We examined the effect of faecal odours from marsupial and eutherian predators, and a native reptilian predator, on the behaviour of three endemic Australian rodent species (the fawn-footed melomys, Melomys cervinipes, the bush rat, Rattus fuscipes, and the giant white-tailed rat, Uromys caudimaculatus) in rainforest remnants on the Atherton Tableland, North Queensland, Australia. Infrared camera traps were used to assess visit rates of rodents to odour stations containing faecal and control odours. Rodents avoided odour stations containing predator faeces, but did not avoid herbivore or control odours. The responses of the three prey species differed: in the late wet season U. caudimaculatus avoided predator odours, whereas R. fuscipes and M. cervinipes did not. In contrast, in the late dry season all three species avoided odour stations containing predator odours. We speculate that these different responses may result from variation in life history traits between the species. (c) 2006 The Association for the Study of Animal Behaviour Published by Elsevier Ltd. All rights reserved.

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To describe the case of a patient with celiac disease who achieved a complete response to a gluten-free diet. A 28-year-old woman presented with diarrhea, oral ulcers, and refractory uveitis of 2.5-years duration. She was treated with prednisone, mydriatic drops, and infliximab with no response. She was referred to our hospital at which point her previous diagnosis of uveitis was confirmed; she was also diagnosed with right-sided sacro-iliitis. The patient did not have arthritis or any skin conditions. Three tests for fecal parasites and a fecal leukocyte were negative. Endoscopy revealed atrophic appearance of the duodenal mucosa. Biopsy showed atrophy of the duodenal villi with intra-epithelial lymphocytes, hyperplasia of the crypts, and chronic inflammatory infiltrate. The search for antiendomysial antibody was > 1/1,280. The patient was started on a gluten-free diet and after 3 months demonstrated significant improvement of gastrointestinal symptoms and uveitis, as well as a reduction of antiendomysial antibodies (1/80). After 6 months, there was complete remission of gastrointestinal symptoms and total control of uveitis. The antiendomysial antibody was negative at that time. Clinical uveitis as a manifestation of celiac disease has been described in only two cases in the literature. This case study is the third to demonstrate that uveitis is a clinical symptom that can be addressed in patients with celiac disease.

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Background: Fibroblast growth factor 23 (FGF23) concentrations increase early in chronic kidney disease (CKD), and the influence of current CKD-mineral and bone disorder (MBD) therapies on serum FGF23 levels is still under investigation. Methods: In this post-hoc analysis of a randomized clinical trial, phosphate binders and calcitriol were washed out of 72 hemodialysis patients who were then submitted to bone biopsy, coronary tomography and biochemical measures, including FGF23. They were randomized to receive sevelamer or calcium acetate for 1 year and the prescription of calcitriol and the calcium concentration in the dialysate were adjusted according to serum calcium, phosphate and PTH and bone biopsy diagnosis. Results: At baseline, bone biopsy showed that 58.3% had low-turnover bone disease, whereas 38.9% had high-turnover bone disease, with no significant differences between them with regard to FGF23. Median baseline FGF23 serum levels were elevated and correlated positively with serum phosphate. After 1 year, serum FGF23 decreased significantly. Repeated measures ANOVA analysis showed that the use of a 3.5-mEq/l calcium concentration in the dialysate, as well as the administration of calcitriol and a calcium-based phosphate binder were associated with higher final serum FGF23 levels. Conclusions: Taken together, our results confirm that the current CKD-MBD therapies have an effect on serum levels of FGF23. Since FGF23 is emerging as a potential treatment target, our findings should be taken into account in the decision on how to manage CKD-MBD therapy. Copyright (C) 2010 S. Karger AG, Basel

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Aortic valve calcium (AVC) can be quantified on the same computed tomographic scan as coronary artery calcium (CAC). Although CAC is an established predictor of cardiovascular events, limited evidence is available for an independent predictive value for AVC. We studied a cohort of 8,401 asymptomatic subjects (mean age 53 10 years, 69% men), who were free of known coronary heart disease and were undergoing electron beam computed tomography for assessment of subclinical atherosclerosis. The patients were followed for a median of 5 years (range 1 to 7) for the occurrence of mortality from any cause. Multivariate Cox regression models were developed to predict all-cause mortality according to the presence of AVC. A total of 517 patients (6%) had AVC on electron beam computed tomography. During follow-up, 124 patients died (1.5%), for an overall survival rate of 96.1% and 98.7% for those with and without AVC, respectively (hazard ratio 3.39, 95% confidence interval 2.09 to 5.49). After adjustment for age, gender, hypertension, dyslipidemia, diabetes mellitus, smoking, and a family history of premature coronary heart disease, AVC remained a significant predictor of mortality (hazard ratio 1.82, 95% confidence interval 1.11 to 2.98). Likelihood ratio chi-square statistics demonstrated that the addition of AVC contributed significantly to the prediction of mortality in a model adjusted for traditional risk factors (chi-square = 5.03, p = 0.03) as well as traditional risk factors plus the presence of CAC (chi-square = 3.58, p = 0.05). In conclusion, AVC was associated with increased all-cause mortality, independent of the traditional risk factors and the presence of CAC. (C) 2010 Published by Elsevier Inc. (Am J Cardiol 2010;106:1787-1791)

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Colonius suggests that, in using standard set theory as the language in which to express our computational-level theory of human memory, we would need to violate the axiom of foundation in order to express meaningful memory bindings in which a context is identical to an item in the list. We circumvent Colonius's objection by allowing that a list item may serve as a label for a context without being identical to that context. This debate serves to highlight the value of specifying memory operations in set theoretic notation, as it would have been difficult if not impossible to formulate such an objection at the algorithmic level.

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Background: Calcium is one of the triggers involved in ischemic neuronal death. Because hypotension is a strong predictor of outcome in traumatic brain injury (TBI), we tested the hypothesis that early fluid resuscitation blunts calcium influx in hemorrhagic shock associated to TBI. Methods: Fifteen ketamine-halothane anesthetized mongrel dogs (18.7 kg +/- 1.4 kg) underwent unilateral cryogenic brain injury. Blood was shed in 5 minutes to a target mean arterial pressure of 40 mm Hg to 45 mm Hg and maintained at these levels for 20 minutes (shed blood volume = 26 mL/kg +/- 7 mL/kg). Animals were then randomized into three groups: CT (controls, no fluid resuscitation), HS (7.5% NaCl, 4 mL/kg, in 5 minutes), and LR (lactate Ringer`s, 33 mL/kg, in 15 minutes). Twenty minutes later, a craniotomy was performed and cerebral biopsies were obtained next to the lesion (""clinical penumbra"") and from the corresponding contralateral side (""lesion`s mirror"") to determine intracellular calcium by fluorescence signals of Fura-2-loaded cells. Results: Controls remained hypotensive and in a low-flow state, whereas fluid resuscitation improved hemodynamic profile. There was a significant increase in intracellular calcium in the injured hemisphere in CT (1035 nM +/- 782 nM), compared with both HS (457 nM +/- 149 nM, p = 0.028) and LR (392 nM +/- 178 nM, p = 0.017), with no differences between HS and LR (p = 0.38). Intracellular calcium at the contralateral, uninjured hemisphere was 438 nM +/- 192 nM in CT, 510 nM +/- 196 nM in HS, and 311 nM +/- 51 nM in LR, with no significant differences between them. Conclusion: Both small volume hypertonic saline and large volume lactated Ringer`s blunts calcium influx in early stages of TBI associated to hemorrhagic shock. No fluid resuscitation strategy promotes calcium influx and further neural damage.

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Although planning is important for the functioning of patients with dementia of the Alzheimer Type (DAT), little is known about response programming in DAT. This study used a cueing paradigm coupled with quantitative kinematic analysis to document the preparation and execution of movements made by a group of 12 DAT patients and their age and sex matched controls. Participants connected a series of targets placed upon a WACOM SD420 graphics tablet, in response to the pattern of illumination of a set of light emitting diodes (LEDs). In one condition, participants could programme the upcoming movement, whilst in another they were forced to reprogramme this movement on-line (i.e. they were not provided with advance information about the location of the upcoming target). DAT patients were found to have programming deficits, taking longer to initiate movements; particularly in the absence of cues. While problems spontaneously programming a movement might cause a greater reliance upon on-line guidance, when both groups were required to guide the movement on-line, DAT patients continued to show slower and less efficient movements implying declining sensori-motor function; these differences were not simply due to strategy or medication status. (C) 1997 Elsevier Science Ltd.