961 resultados para INCREASED EXPRESSION


Relevância:

70.00% 70.00%

Publicador:

Resumo:

Aims Following sinoaortic denervation (SAD), isolated rat aortas present oscillatory contractions and demonstrate a heightened contraction for alpha-adrenergic agonists. Our aim was to verify the effects of SAD on connexin43 (Cx43) expression and phenylephrine-induced contraction in isolated aortas. Methods and results Three days after surgery (SAD or sham operation), isolated aortic rings were exposed to phenylephrine and acetylcholine (0.1-10 mu M) in the presence or absence of the gap junction blocker 18 beta-glycyrrhetinic acid (18 beta-GA, 100 mu M). Vascular reactivity to potassium chloride (KCl, 4.7-120 mM) was also examined. The incidence of rats presenting oscillatory contractions was measured. Effects of SAD on the vascular smooth muscle expression of the Cx43 mRNA by RT-PCR and western blotting for Cx43 protein were examined. Phenylephrine-induced contraction was higher in SAD rat aortas compared with the control. In the presence of 18 beta-GA, the response to phenylephrine was similar in both groups. Oscillatory contractions were observed in 10/10 SAD rat aortas vs. 2/10 controls. Relaxing response to acetylcholine was similar in both groups, but in the presence of 18 beta-GA, the response to acetylcholine decreased significantly in the sham-operated group (82.7 +/- 7.6% reduction of relaxation), whereas a half-maximal relaxation (reduction of 46.2 +/- 5.3%) took place in SAD rat aortas. KCl-induced contraction was similar in both groups. Following SAD, RT-PCR revealed significantly increased levels of Cx43 mRNA (9.85 fold, P < 0.01). Western blot analysis revealed greater levels of Cx43 protein (P < 0.05). Conclusion Blood pressure variability evoked by SAD leads to increased expression of Cx43, which could contribute to enhanced phenylephrine-induced contraction and oscillatory activity in isolated aortas.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

We evaluate osmotic and chloride (Cl(-)) regulatory capability in the diadromous shrimp Macrobrachium amazonicum, and the accompanying alterations in hemolymph osmolality and [Cl(-)], gill Na(+)/K(+)-ATPase activity, and expression of gill Na(+)/K(+)-ATPase alpha-subunit and V-ATPase B subunit mRNA during salinity (S) acclimation. We also characterize V-ATPase kinetics and the organization of transport-related membrane systems in the gill epithelium. Macrobrachium amazonicum strongly hyper-regulates hemolymph osmolality and [Cl(-)] in freshwater and in salinities up to 25 parts per thousand S. During a 10-day acclimation period to 25 parts per thousand S, hemolymph became isosmotic and hypo-chloremic after 5 days, [Cl(-)] alone remaining hyporegulated thereafter. Gill Na(+)/K(+)-ATPase alpha-subunit mRNA expression increased 6.5 times initial values after 1 h, then decreased to 3 to 4 times initial values by 24 h and to 1.5 times initial values after 10 days at 25 parts per thousand S. This increased expression was accompanied by a sharp decrease at 5 h then recovery of initial Na(+)/K(+)-ATPase activity within 24 h, declining again after 5 days, which suggests transient Cl(-) secretion. V-ATPase B-subunit mRNA expression increased 1.5-fold within 1 h, then reduced sharply to 0.3 times initial values by 5 h, and remained unchanged for the remainder of the 10-day period. V-ATPase activity dropped sharply and was negligible after a 10-day acclimation period to 21 parts per thousand S, revealing a marked downregulation of ion uptake mechanisms. The gill epithelium consists of thick, apical pillar cell flanges, the perikarya of which are coupled to an intralamellar septum. These two cell types respectively exhibit extensive apical evaginations and deep membrane invaginations, both of which are associated with numerous mitochondria, characterizing an ion transporting epithelium. These changes in Na(+)/K(+)- and V-ATPase activities and in mRNA expression during salinity acclimation appear to underpin ion uptake and Cl(-) secretion by the palaemonid shrimp gill.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

Several differences have been described between neonatal and adult immune responses. The predisposition in early life to Th2-type response or tolerance makes it a susceptible period for infections and allergic sensitization. The aim of this work was to evaluate the effects of CpG-containing oligodeoxynucleotides on neonatal and adult immunization with ovalbumin and Blomia tropicalis extract and compare the CpG effects on B and T cells of neonatal and adult mice. Mice that received CpG showed reduced immunoglobulin E (IgE) antibody production in both neonatal and adult periods, in parallel to increased IgG2a antibody levels. We observed that spleen cells of mice that received CpG in early life produced increased amounts of interferon-gamma upon anti-CD3 stimulation. Negative regulation of IgE response was more pronounced in adult than neonate mice; further, CpG decreased anaphylactic antiovalbumin IgG1 only in adults. Also, an upregulation of toll-like receptor 9 expression was detected in adult B cells, but not in neonatal, upon CpG stimuli. Neonatal B cells showed enhanced interleukin (IL)-10 expression and decreased IL-6 levels than adult B cells in response to CpG. When we analyzed in vitro activation of CD4+ T cells, an increased expression of B7 molecules on T cells in neonates was suppressed by CpG. Altogether, we verified qualitative and quantitative evidences regarding CpG effect on neonatal and adult allergens immunizations, which points to the importance of understanding neonatal immune system to establish immunomodulatory strategies for prevention of allergic diseases.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

Purpose: Subclinical inflammation may be observed in patients, using topical antiglaucomatous drugs. The objective,e of this study was to investigate inflammation in conjunctiva of glaucoma patients using prostaglandin analogs, by the detection of a immunogenetic marker (HLA-DR) and compare the effect of 3 different drugs: latanoprost, bimatoprost, and travoprost in the induction of this inflammation. Subjects and Methods: Thirty-three patients with primary open-angle glaucoma were evaluated without and with prostaglandin analogs topical therapy. Imprints of conjunctival cells were obtained, fixed on glass slides. and Prepared for immunohistochemical analysis. Results: Before the use of prostaglandin analogs, 4 of the 33 patients evaluated presented expression (of HLA-DR in the conjunctiva (mild). After 1 month oil prostaglandin analog treatment, all but 1 patient presented HLA-DR staining. HLA-DR expression of these 32 patients was scored as mild (19 patients), medium (11 patients), or intense (2 patients). The differences were statistically significant both when the presence and the increased expression of HLA-DR were considered (P<0.001). When the 3 different groups were analyzed (latanoprost, bimatoprost, and travoprost) no statistically significant difference was round (P 0.27). Conclusions: The use of prostaglandin analogs eye drops provokes, a reaction, observed by HLA-DR subclinical inflammatory expression, even after a short period of treatment, independently of the class of the prostaglandin analogs used.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

Some studies have demonstrated the involvement of nuclear factor-kappa B (NF-kB) in the pathogenesis of glomerulonephritis. The aim of our study was twofold: (1) to analyze the prognostic value of NF-kB expression in primary IgA nephropathy (IgAN) and (2) to compare the results of NF-kB expression by immunohistochemistry (IHC) and southwestern histochemistry (SWH). We analyzed 62 patients diagnosed with IgAN from 1987 to 2003. We used monoclonal antibodies to CD68 and mast cell tryptase and polyclonal antibodies to TGF-beta 1, alpha-SMA and NF-kB p65. We used SWH for the in situ detection of activated NF-kB. The results showed that NF-kB expression (mainly by SWH) correlated with clinical and histological parameters. An unfavorable clinical course of IgAN was significantly related to tubular NF-kB expression by SWH, but not by IHC. The Kaplan-Meier curves demonstrated that increased NF-kB expression, which was measured by IHC and SWH, decreased renal survival. In conclusion, the increased expression of NF-kB in the tubular area may be a predictive factor for the poor prognosis of patients with IgAN. Compared with IHC, NF-kB expression determined by SWH was correlated with a larger number of parameters of poor disease outcome.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

We found an increased expression of the TAGLN gene in endometriotic lesions compared with the eutopic endometrium of the same patients by real-time polymerase chain reaction. It is possible that this deregulation contributes to the development and maintenance of endometriosis by being involved in the pathways of organization of cytoskeletal architecture. (Fertil Steril (R) 2011;96:700-3. (C)2011 by American Society for Reproductive Medicine.)

Relevância:

70.00% 70.00%

Publicador:

Resumo:

Neospora caninum is one of the main causes of abortion and natimortality in cattle. Host immune defense is capable to inhibit tachyzoite activity during acute infection, but there is no action against bradyzoites in tissue cysts. Activation and modulation of this response is controlled by cell mediators. The real-time RT-PCR technique was employed to detect some of those mediators during N. caninum infection. Holstein and Nelore calves intramuscularly infected with tachyzoites and uninfected controls were slaughtered at the sixth day post-infection and popliteal lymph node, liver and brain cortex samples were analyzed. Real-time RT-PCR detected gene expression in all tissues. No significant variation of GAPDH gene expression was detected among groups, its amplification efficiency was similar to the other genes tested and it was used as the endogenous control for the analysis. Comparisons between infected and uninfected groups allowed the relative gene expression quantification. IFN-gamma and TNF-alpha genes showed increased expression in some samples. iNOS and TGF-beta 1 genes had some non-significant variations and IL-4 and IL-10 stayed pratically inaltered.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

Aims: Claudins, a large family of essential tight junction (TJ) proteins, are abnormally regulated in human carcinomas. The aim of this study was to determine the expression of claudins 1, 2, 3, 4, 5, 7, and 11 in prostate samples from Brazilian patients and correlate it with the clinicopathological features of prostate cancer. Methods: Using a tissue microarray (TMA) of specimens of prostate adenocarcinoma and benign prostatic hyperplasia (BPH) we analysed the expression of claudins 1, 2, 3, 4, 5, 7, and 11 by immunohistochemistry. Results: Claudin 4 was down-regulated and claudins 2, 3, and 5 were overexpressed in prostate adenocarcinomas compared with BPH samples. Expression of claudins 1 and 7 was similar in tumours and BPH samples. Claudin 11 was absent from all prostate samples. Overexpression of claudin 3 was associated with perineural invasion (p = 0.014) and tended to occur in advanced stages of the disease (p = 0.064). Increased expression of claudin 5 was marginally associated with perineural invasion (p = 0.060). Conclusions: Our results suggest that alterations in claudin expression occur in prostate cancer cells, although we have not found an association with the main clinicopathological parameters.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

Oral cancer is the eighth most prevalent cancer worldwide. It causes significant mortality and morbidity rates, which have motivated the search for prognostic factors to better tailor the individual management of oral squamous cell carcinoma patients. Nucleophosmin is a multifunctional protein that is involved in many cellular activities, such as, regulation of the tumor suppressor genes TP53 and p14(ARF). and is associated with proliferative and growth suppressive roles in the cell. Nucleophosmin is overexpressed in many solid tumors in human, including tumors of the colon, liver, stomach, ovary, and prostate. In this study, we analyzed the expression of nucleophosmin, Ki-67, and p53 by immunohistochemistry in oral squamous cell carcinomas. Less than 10% of nuclear staining was observed in 90.3%, 50.6%, and 65.3% of the cases for nucleophosmin, p53, and Ki-67, respectively. Expression of p53 was not significantly associated with any of the clinicopathologic parameters analyzed. Increased expression of Ki-67 was associated with the presence of lymph node metastasis (P < .0001), advanced stages of disease (P = .0030), tumors occurring in the floor of mouth (P = .0018), and moderately/well-differentiated tumors (P = .0287). Local recurrence was associated with higher expression of nucleophosmin (P = .0233), and disease-free survival rate was significantly better in patients with low expression of nucleophosmin. Multivariate analysis suggested that expression of nucleophosmin could be an independent prognostic factor for oral squamous cell carcinoma patients. (C) 2010 Elsevier Inc. All rights reserved.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

There are at present disparate published results with regard to the relevance of the Bcl-2 gene family, levels of apoptosis, and cell proliferation in the development and progression of renal cell carcinoma (RCC). The present study v analyses the interrelationship between the expression of representatives of the anti-apoptotic (Bcl-2, Bcl-X-L) or pro-apoptotic (Bax) Bcl-2 proteins, incidence of apoptosis, and mitosis in a selected small group of 22 graded RCCs that had paired normal renal tissue, or non-neoplastic tissue in the renal biopsy specimen. The cases were chosen to determine the feasibility of measuring these parameters as potential surrogate markers of progression or treatment failure of the cancers. The results showed that in approximately 50% of the RCCs, where Bcl-2 and/or Bcl-X-L expression was high, apoptosis it-as not detected, and when expression of these proteins was low or not found, increased levels of apoptosis were seen. In most of the remaining 50% of samples, high levels of Bcl-X-L but not Bcl-2 were negatively correlated with low levels of apoptosis (Bcl-X-L: r = -0.437, P = 0.07 and Bcl-2: r = + 0.560, P = 0.02). For the same group of samples, high Bax expression was found in association with apoptosis (r = + 0.578, P = 0,02). A novel finding was an association between low expression of Bcl-2 an/or Bcl-X-L in normal tissue and the level of expression of these proteins in the RCCs, an intrinsic variation that may be an individual patient factor. The results indicate that, in RCCs with increased expression of Bcl-2 and/or Bcl-X-L, levels of apoptosis are minimal and these combined factors may assist in progression of the cancers and resistance to treatments.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

Problem: The present study was performed to explore the effects of pregnancy on experimental autoimmune encephalomyelitis (EAE) induced in Lewis rats by inoculation with myelin basic protein (MBP) (MBP-EAE). Method of study: MBP-EAE was induced in pregnant and non-pregnant rats and severity of disease evaluated. Serum from pregnant and non-pregnant rats was used in standard lymphocyte proliferation assays. Real-time polymerase chain reaction (PCR) was used to investigate the expression of cytokine mRNA in the inflammatory cells obtained from the spinal cord of rats on day 15 after inoculation. Results: Pregnant rats developed less severe disease than non-pregnant rats. Serum from pregnant rats suppressed the proliferation of T lymphocytes in response to MBP. There was significantly increased expression of IL-4. IL-10 and TNF-alpha mRNA in the spinal cord infiltrate of pregnant rats. Conclusion: Circulating humoral factors and alteration in cytokine production by inflammatory cells may contribute to the suppression of EAE in pregnant rats.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

The contribution of the UV component of sunlight to the development of skin cancer is widely acknowledged, although the molecular mechanisms that are disrupted by UV radiation (UVR) resulting in the loss of normal growth controls of the epidermal stem cell keratinocytes and melanocytes is still poorly understood. alpha-Melanocyte stimulating hormone (alpha-MSH), acting via its receptor MC1, has a key role in skin pigmentation and the melanizing response after exposure to UVR. The cell cycle inhibitor p16/CDKN2A also appears to have an important function in a cell cycle checkpoint response in skin after exposure to UVR. Both of these genes have been identified as risk factors in skin cancer, MC1R variants are associated with increased risk to both melanoma and nonmelanoma skin cancers, and p16/CDKN2A with increased risk of melanoma. Here we demonstrate that the increased expression of p16 after exposure to sub-erythemal doses of UVR is potentiated by alpha-MSH, a ligand for MC1R, and this effect is mimicked by cAMP, the intracellular mediator of alpha-MSH signaling via the MC1 receptor. This link between p16 and MC1R may provide a molecular basis for the increased skin cancer risk associated with MC1R polymorphisms.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

Expression of the mRNAs encoding the astrocytic (EAAT1, EAAT2) and neuronal (EAAT3, EAAT4) excitatory amino acid transporters and the AMPA-type glutamate receptor subunits GluR2 and GluR3 was investigated in postmortem cerebellar extracts from a patient with olivopontocerebellar atrophy (OPCA) and in material from three age-matched controls. Decreased expression in the steady state level of EAAT4 mRNA in the OPCA sample was correlated with the selective loss of Purkinje cells. Neuropathological evaluation revealed reactive gliosis and concomitantly increased expression of the mRNA encoding astrocytic glial fibrillary acidic protein (GFAP). Expression of the mRNAs encoding the AMPA receptor subunits GluR2 and GluR3 subunits was found to be decreased in OPCA suggesting that excitotoxic mechanism could play a role in the pathogenesis of the selective neuronal cell death in this disorder.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

Background - Marfan syndrome (MS) is a genetic disorder caused by a mutation in the fibrillin gene FBN1. Bicuspid aortic valve (BAV) is a congenital heart malformation of unknown cause. Both conditions are associated with ascending aortic aneurysm and premature death. This study examined the relationship among the secretion of extracellular matrix proteins fibrillin, fibronectin, tenascin, and vascular smooth muscle cell (VSMC) apoptosis. The role of matrix metalloproteinase (MMP)- 2 in VSMC apoptosis was studied in MS aneurysm. Methods and Results - Aneurysm tissue was obtained from patients undergoing surgery ( MS: 4 M, 1 F, age 27 - 45 years; BAV: 3 M, 2 F, age 28 - 65 years). Normal aorta from subjects with nonaneurysm disease was also collected ( 4 M, 1 F, age 23 - 93 years). MS and BAV aneurysm histology showed areas of cystic medial necrosis (CMN) without inflammatory infiltrate. Immunohistochemical study of cultured MS and BAV VSMC showed intracellular accumulation and reduction of extracellular distribution of fibrillin, fibronectin, and tenascin. Western blot showed no increase in expression of fibrillin, fibronectin, or tenascin in MS or BAV VSMC and increased expression of MMP-2 in MS VSMCs. There was 4-fold increase in loss of cultured VSMC incubated in serum-free medium for 24 hours in both MS ( 27 +/- 8%) and BAV ( 32 +/- 14%) compared with control ( 7 +/- 5%). Conclusions - In MS and BAV there is alteration in both the amount and quality of secreted proteins and an increased degree of VSMC apoptosis. Up-regulation of MMP-2 might play a role in VSMC apoptosis in MS VSMC. The findings suggest the presence of a fundamental cellular abnormality in BAV thoracic aorta, possibly of genetic origin.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

Cytokines are important for breast cell function, both as trophic hormones and as mediators of host defense mechanisms against breast cancer. Recently, inducible feedback suppressors of cytokine signalling (SOCS/JAB/SSI) have been identified, which decrease cell sensitivity to cytokines. We examined the expression of SOCS genes in 17 breast carcinomas and 10 breast cancer lines, in comparison with normal tissue and breast lines. We report elevated expression of SOCS-1-3 and CIS immunoreactive proteins within in situ ductal carcinomas and infiltrating ductal carcinomas relative to normal breast tissue. Significantly increased expression of SOCS-1-3 and CIS transcripts was also shown by quantitative in situ hybridisation within both tumour tissue and reactive stroma. CIS transcript expression was elevated in all 10 cancer lines, but not in control lines. However, there was no consistent elevation of other SOCS transcripts. CIS protein was shown by immunoblot to be present in all cancer lines at increased levels, mainly as the 47 kDa ubiquitinylated form. A potential proliferative role for CIS overexpression is supported by reports that CIS activates ERK kinases, and by strong induction in transient reporter assays with an ERK-responsive promoter. The in vivo elevation of SOCS gene expression may be part of the host/tumour response or a response to autocrine/paracrine GH and prolactin. However, increased CIS expression in breast cancer lines appears to be a specific lesion, and could simultaneously shut down STAT 5 signalling by trophic hormones, confer resistance to host cytokines and increase proliferation through ERK kinases.