Evaluation of the influence of different types of seats on postural control in individuals with paraplegia

Study design: Cross-sectional study. Objectives: To assess the importance of proprioceptive and vision information on different types of wheelchair seats with regard to postural control in paraplegic individuals during static posture. Setting: Centre of Rehabilitation at the University Hospital/FMRP-USP and Rehabilitation Outpatient Clinic at University Hospital/UNICAMP, Brazil. Methods: This study involved 11 individuals with paraplegia. All individuals were submitted to an evaluation of static balance with their eyes open and closed in three different types of seats: wheelchair seat, foam seat and gel seat. Balance evaluation was performed by using the Polhemus system, in which body displacements and anteroposterior and mediolateral speeds were assessed in a static seated position in the different types of seats. Data were analyzed using analysis of variance. The differences were considered at P<0.05. Results: No statistical differences were found between the three types of seats in terms of displacements and anteroposterior and mediolateral speeds, or between seats with individuals keeping their eyes open or closed (P>0.05). However, it was observed that body displacements were more prominent toward an anteroposterior than a mediolateral direction. Conclusion: This study suggests that individuals with paraplegia tend to exhibit a more anteroposterior body displacement than a mediolateral one, with no significant differences between the types of seats in both situations of eyes open and closed. Spinal Cord (2010) 48, 825-827; doi:10.1038/sc.2010.30; published online 30 March 2010

Major histocompatibility complex (MHC) class II but not MHC class I molecules are required for efficient control of Strongyloides venezuelensis infection in mice

P>Strongyloides stercoralis is an intestinal nematode capable of chronic, persistent infection and hyperinfection of the host; this can lead to dissemination, mainly in immunosuppressive states, in which the infection can become severe and result in the death of the host. In this study, we investigated the immune response against Strongyloides venezuelensis infection in major histocompatibility complex (MHC) class I or class II deficient mice. We found that MHC II(-/-) animals were more susceptible to S. venezuelensis infection as a result of the presence of an elevated number of eggs in the faeces and a delay in the elimination of adult worms compared with wild-type (WT) and MHC I(-/-) mice. Histopathological analysis revealed that MHC II(-/-) mice had a mild inflammatory infiltration in the small intestine with a reduction in tissue eosinophilia. These mice also presented a significantly lower frequency of eosinophils and mononuclear cells in the blood, together with reduced T helper type 2 (Th2) cytokines in small intestine homogenates and sera compared with WT and MHC I(-/-) animals. Additionally, levels of parasite-specific immunoglobulin M (IgM), IgA, IgE, total IgG and IgG1 were also significantly reduced in the sera of MHC II(-/-) infected mice, while a non-significant increase in the level of IgG2a was found in comparison to WT or MHC I(-/-) infected mice. Together, these data demonstrate that expression of MHC class II but not class I molecules is required to induce a predominantly Th2 response and to achieve efficient control of S. venezuelensis infection in mice.

Preliminary analysis of miRNA pathway in Schistosoma mansoni

RNA silencing refers to a series of nuclear and cytoplasmatic processes involved in the post-transcriptional regulation of gene expression or post-transcriptional gene silencing (PTGS), either by sequence-specific mRNA degradation or by translational at-rest. The best characterized small RNAs are microRNAs (miRNAs), which predominantly perform gene silencing through post-transcriptional mechanisms. in this work we used bioinformatic approaches to identify the parasitic trematode Schistosoma Mansoni sequences that are similar to enzymes involved in the post-transcriptional gene silencing mediated by miRNA pathway. We used amino acid sequences of well-known proteins involved in the miRNA pathway against S. mansoni genome and transcriptome databases identifying a total of 13 Putative proteins in the parasite. In addition, the transcript levels of SinDicer1 and SmAgo2/3/4 were identified by qRT-PCR using cercariae, adult worms, eggs and in vitro Cultivated schistosomula. Our results showed that the SmDicer1 and SmAgo2/3/4 are differentially expressed during schistosomula development, suggesting that the miRNA pathway is regulated at the transcript level and therefore may control gene expression during the life cycle of S. mansoni. (C) 2008 Published by Elsevier Ireland Ltd.

CCR2 receptor is essential to activate microbicidal mechanisms to control Toxoplasma gondii infection in the central nervous system

Chemokines comprise a structurally related family of cytokines that regulate leukocyte trafficking. Because infection with Toxoplasma gondii can induce an important inflammatory reaction that, if left uncontrolled, can lead to death, we investigated the role of the chemokine receptor CCR2 in T gondii infection. We orally infected CCR2(-/-) mice with five ME-49 T gondii cysts and monitored morbidity, survival, and immune response thereafter. The CCR2(-/-) mice displayed higher susceptibility to infection as all mice died on day 28 after infection. Despite similar Th1 responses, a more evident anti-inflammatory response was induced in the peripheral organs of CCR2(-/-) mice compared with wild-type C57BL/6 mice. Additionally, CCR2-/- mice presented greater parasitism and a milder inflammatory reaction in their peripheral organs with lesser CD4(+) and MAC-1(+) and greater CD8(+) cell migration. The parasite load decreased in these organs in CCR2(-/-) mice but remained uncontrolled in the central nervous system. Additionally, we observed down-regulated inducible nitric oxide synthase expression in peripheral organs from CCR2(-/-) mice that was associated with a small nitric oxide production by spleen macrophages. In conclusion, in the absence of CCR2, another mechanism is activated to control tissue parasitism in peripheral organs. Nevertheless, CCR2 is essential for the activation of microbicidal mediators that control T gondii replication in the central nervous system.

Cell homeostasis in a Leishmania major mutant overexpressing the spliced leader RNA is maintained by an increased proteolytic activity

Although several stage-specific genes have been identified in Leishmania, the molecular mechanisms governing developmental gene regulation in this organism are still not well understood. We have previously reported an attenuation of virulence in Leishmania major and L braziliensis carrying extra-copies of the spliced leader RNA gene. Here, we surveyed the major differences in proteome and transcript expression profiles between the spliced leader RNA overexpressor and control lines using two-dimensional gel electrophoresis and differential display reverse transcription PCR, respectively. Thirty-nine genes related to stress response, cytoskeleton, proteolysis, cell cycle control and proliferation, energy generation, gene transcription, RNA processing and post-transcriptional regulation have abnormal patterns of expression in the spliced leader RNA overexpressor line. The evaluation of proteolytic pathways in the mutant revealed a selective increase of cysteine protease activity and an exacerbated ubiquitin-labeled protein population. Polysome profile analysis and measurement of cellular protein aggregates showed that protein translation in the spliced leader RNA overexpressor line is increased when compared to the control line. We found that L major promastigotes maintain homeostasis in culture when challenged with a metabolic imbalance generated by spliced leader RNA surplus through modulation of intracellular proteolysis. However, this might interfere with a fine-tuned gene expression control necessary for the amastigote multiplication in the mammalian host. (c) 2010 Elsevier Ltd. All rights reserved.

Differential expression of hypoxia pathway genes in honey bee (Apis mellifera L.) caste development

Diphenism in social bees is essentially contingent on nutrient-induced cellular and systemic physiological responses resulting in divergent gene expression patterns. Analyses of juvenile hormone (JH) titers and functional genomics assays of the insulin-insulin-like signaling (IIS) pathway and its associated branch, target-of-rapamycin (TOR), revealed systemic responses underlying honey bee (Apis mellifera) caste development. Nevertheless, little attention has been paid to cellular metabolic responses. Following up earlier investigations showing major caste differences in oxidative metabolism and mitochondrial physiology, we herein identified honey bee homologs of hypoxia signaling factors, HIF alpha/Sima, HIF beta/Tango and PHD/Fatiga and we investigated their transcript levels throughout critical stages of larval development. Amsima, Amtango and Amfatiga showed correlated transcriptional activity, with two peaks of occurring in both queens and workers, the first one shortly after the last larval molt and the second during the cocoon-spinning phase. Transcript levels for the three genes were consistently higher in workers. As there is no evidence for major microenvironmental differences in oxygen levels within the brood nest area, this appears to be an inherent caste character. Quantitative PCR analyses on worker brain, ovary, and leg imaginal discs showed that these tissues differ in transcript levels. Being a highly conserved pathway and linked to IIS/TOR, the hypoxia gene expression pattern seen in honey bee larvae denotes that the hypoxia pathway has undergone a transformation, at least during larval development, from a response to environmental oxygen concentrations to an endogenous regulatory factor in the diphenic development of honey bee larvae. (C) 2010 Elsevier Ltd. All rights reserved.

Multiple recurrent genetic events converge on control of histone lysine methylation in medulloblastoma

We used high-resolution SNP genotyping to identify regions of genomic gain and loss in the genomes of 212 medulloblastomas, malignant pediatric brain tumors. We found focal amplifications of 15 known oncogenes and focal deletions of 20 known tumor suppressor genes (TSG), most not previously implicated in medulloblastoma. Notably, we identified previously unknown amplifications and homozygous deletions, including recurrent, mutually exclusive, highly focal genetic events in genes targeting histone lysine methylation, particularly that of histone 3, lysine 9 (H3K9). Post-translational modification of histone proteins is critical for regulation of gene expression, can participate in determination of stem cell fates and has been implicated in carcinogenesis. Consistent with our genetic data, restoration of expression of genes controlling H3K9 methylation greatly diminishes proliferation of medulloblastoma in vitro. Copy number aberrations of genes with critical roles in writing, reading, removing and blocking the state of histone lysine methylation, particularly at H3K9, suggest that defective control of the histone code contributes to the pathogenesis of medulloblastoma.

Transcriptional changes in U343 MG-a glioblastoma cell line exposed to ionizing radiation

Glioblastoma multiforme (GBM) is a highly invasive and radioresistant brain tumor. Aiming to study how glioma cells respond to gamma-rays in terms of biological processes involved in cellular responses, we performed experiments at cellular context and gene expression analysis in U343-MG-a GBM cells irradiated with 1 Gy and collected at 6 h post-irradiation. The survival rate was approximately 61% for 1 Gy and was completely reduced at 16 Gy. By performing the microarray technique, 859 cDNA clones were analyzed. The Significance Analysis of Microarray algorithm indicated 196 significant expressed genes (false discovery rate (FDR) = 0.42%): 67 down-regulated and 97 up-regulated genes, which belong to several classes: metabolism, adhesion/cytoskeleton, signal transduction, cell cycle/apoptosis, membrane transport, DNA repair/DNA damage signaling, transcription factor, intracellular signaling, and RNA processing. Differential expression patterns of five selected genes (HSPA9B, INPP5A, PIP5K1A, FANCG, and TPP2) observed by the microarray analysis were further confirmed by the quantitative real time RT-PCR method, which demonstrated an up-regulation status of those genes. These results indicate a broad spectrum of biological processes (which may reflect the radio-resistance of U343 cells) that were altered in irradiated glioma cells, so as to guarantee cell survival.

Transcriptional Response of Peripheral Lymphocytes to Early Fibrosarcoma: A Model System for Cancer Detection Based on Hybridization Signatures

Since circulating leukocytes, mainly B and T cells, continuously maintain vigilant and comprehensive immune surveillance, these cells could be used as reporters for signs of infection or other pathologies, including cancer. Activated lymphocyte clones trigger a sensitive transcriptional response, which could be identified by gene expression profiling. To assess this hypothesis, we conducted microarray analysis of the gene expression profile of lymphocytes isolated from immunocompetent BALB/c mice subcutaneously injected with different numbers of tumorigenic B61 fibrosarcoma cells. Flow cytometry demonstrated that the number of circulating T (CD3(+)CD4(+) or CD3(+)CD8(+)) or B (CD19(+)) cells did not change. However, the lymphocytes isolated from tumor cell-injected animals expressed a unique transcriptional profile that was identifiable before the development of a palpable tumor mass. This finding demonstrates that the transcriptional response appears before alterations in the main lymphocyte subsets and that the gene expression profile of peripheral lymphocytes can serve as a sensitive and accurate method for the early detection of cancer. Exp Biol Med 234:802-812, 2009

Paracoccidioidomycosis in Patients Infected with and Not Infected with Human Immunodeficiency Virus: A Case-Control Study

Epidemiologic and clinical data for 53 patients with paracoccidioidomycosis and co-infected with human immunodeficiency virus (HIV) (cases) were compared with those for 106 patients with endemic paracoccidioidomycosis (controls). The prevalence of Paracoccidioides brasiliensis co-infection was estimated in 1.4% in cases of acquired immunodeficiency syndrome (AIDS). Patients co-infected with HIV were younger, less involved in agricultural occupations; 83.7% had CD4+ cell count < 200 cells/mu L. Paracoccidioidomycosis in co-infected patients usually showed a rapid progression, with more fever, frequent involvement of the lungs, and multiple extrapulmonary lesions. The response to antifungal therapy and deaths caused by paracoccidioidomycosis were similar in the two patient groups, but late relapses were more common in co-infected cases. Paracoccidioidomycosis in HIV-infected patients shows epidemiologic and clinical characteristics differing from those of the endemic disease and should be considered an AIDS-defining opportunistic infection in Latin America.

Genetic Susceptibility Loci in Rheumatoid Arthritis Establish Transcriptional Regulatory Networks with Other Genes

Linkage studies have identified the human leukocyte antigen (HLA)-DRB1 as a putative rheumatoid arthritis (RA) susceptibility locus (SL). Nevertheless, it was estimated that its contribution was partial, suggesting that other non-HLA genes may play a role in RA susceptibility. To test this hypothesis, we conducted microarray transcription profiling of peripheral blood mononuclear cells in 15 RA patients and analyzed the data, using bioinformatics programs (significance analysis of microarrays method and GeneNetwork), which allowed us to determine the differentially expressed genes and to reconstruct transcriptional networks. The patients were grouped according to disease features or treatment with tumor necrosis factor blocker. Transcriptional networks that were reconstructed allowed us to identify the interactions occurring between RA SL and other genes, for example, HLA-DRB1 interacting with FNDC3A (fibronectin type III domain containing 3A). Given that fibronectin fragments can stimulate mediators of matrix and cartilage destruction in RA, this interaction is of special interest and may contribute to a clearer understanding of the functional role of HLA-DRB1 in RA pathogenesis.

Effect of the glycemic control on intracellular cytokine production from peripheral blood mononuclear cells of type 1 and type 2 diabetic patients

Aims: To evaluate the intracellular production of tumor necrosis factor (TNF-alpha), interleukine-6 (IL-6), INF-gamma, IL-8 and IL-10 in peripheral blood lympbomononuclear cells from type 1 and type 2 diabetic patients, stratified according to the glycemic control. Methods: Thirty-five diabetic patients (17 type 1 and 18 type 2) and nine healthy individuals paired to patients in terms of sex and age were studied. Nine patients of each group were on inadequate glycemic controls. Intracellular cytokines were evaluated using flow cytometry. Cell cultures were stimulated with LPS to evaluate TNF-alpha and IL-6 or with PMA and lonomycin to evaluate IFN-gamma, IL-8 and IL-10 intracellular staining. Results: The percentages of CD33(+) cells bearing TNF-alpha and CD3(+) cells bearing IL-10 were increased in type 1 diabetic patients with inadequate glycemic control in relation to those with adequate control. In contrast, the percentage of CD3(+) cells bearing IL-8 was decreased in type 2 patients under inadequate glycemic control. Conclusions: The glycemic control is important for the detection of intracellular cytokines, and may contribute towards the susceptibility to infections in diabetic patients. (c) 2008 Elsevier Ireland Ltd. All rights reserved.

A pilot case-control association study of cytokine polymorphisms in Brazilian women presenting with HPV-related cervical lesions

Objective and study design: A case-control study was conducted on 42 Brazilian women presenting with human papilloma virus (HPV) infection and cervical lesion and 87 HPV-negative women to evaluate single nucleotide polymorphisms observed in TNF-alpha, TGF-beta, IL-10, IL-6, and IFN-gamma genes. Results and conclusion: No significant association was observed on the cytokine polymorphisms analyzed in this series. Larger studies using cytokine polymorphisms may be useful for providing further information regarding their influence or not in HPV-related cervical lesions. (C) 2008 Elsevier Ireland Ltd. All rights reserved.

Effects of periodontal therapy on glycemic control and inflammatory markers

Background: Periodontitis, a complication of diabetes mellitus (DM), can induce or perpetuate systemic conditions. This double-masked, placebo-controlled study evaluated the effects of periodontal therapy (scaling and root planing [SRP]) on the serum levels of glycated hemoglobin (HbA1c) and on inflammatory biomarkers. Methods: Thirty subjects with type 2 DM and periodontitis were treated with SRP + placebo (SRP; N = 15) or with SRP + doxycycline (SRP+Doxy; N = 15), 100 mg/day, for 14 days. Clinical and laboratory data were recorded at baseline and at 3 months after treatment. Results: After 3 months, the reduction in probing depth Was 0.8 mm for the SRP group (P <0.01) and 1.1 mm for the SRP+Doxy group (P <0.01) followed by a 0.9% (SRP; P = 0.17) and 1.5% (SRP+Doxy; P<0.01) reduction in HbA1c levels. A significant reduction in interleukin (IL)-6; interferon-inducible protein 10; soluble fas ligand; granulocyte colony-stimulating factor; RANTES; and IL-12 p70 serum levels were also verified (N = 30). To our knowledge, this is the first report on the effects of periodontal therapy on multiple systemic inflammatory markers in DM. Conclusions: Periodontal therapy may influence the systemic conditions of patients with type 2 DM, but no statistical difference was observed with the adjunctive systemic doxycycline therapy. Moreover, it is possible that the observed improvement in glycemic control and in the reduction of inflammatory markers could also be due to diet, which was not controlled in our study. Therefore, a confirmatory study with a larger sample size and controlled diet is necessary.

Ethanol consumption increases blood pressure and alters the responsiveness of the mesenteric vasculature in rats

Chronic ethanol Consumption and hypertension are related. In the current study we investigated whether changes in reactivity of the mesenteric arterial bed could account for the increased blood pressure associated with chronic ethanol intake. Changes in reactivity to phenylephrine and acetylcholine were investigated in the perfused mesenteric bed from rats treated with ethanol for 2 or 6 weeks and their age-matched controls. Mild hypertension was observed in chronically ethanol-treated rats. Treatment of rats for 6 weeks induced an increase in the contractile response of endothelium-intact mesenteric bed to phenylephrine, but not denuded rat mesenteric bed. The phenylephrine-induced increase in perfusion pressure was not altered after 2 weeks` treatment with ethanol. Moreover, acetylcholine-induced endothelium-dependent relaxation was reduced by ethanol treatment for 6 weeks, but not 2 weeks. Pre-treatment with indometacin, a cyclooxygenase inhibitor, reduced the maximum effect induced by phenylephrine (E-max) in endothelium-intact mesenteric bed from both control and ethanol-treated rats. No differences in the E-max values for phenylephrine were observed between groups in the presence of indometacin. L-NNA, a nitric oxide (NO) synthase (NOS) inhibitor, increased the E-max for phenylephrine in endothelium-intact mesenteric bed from control rats but not from ethanol-treated rats. Levels of endothelial NOS (eNOS) mRNA were not altered by chronic ethanol consumption. However, chronic ethanol intake strongly reduced eNOS protein levels in the mesenteric bed. This study shows that chronic ethanol consumption increases blood pressure and alters the reactivity of the mesenteric bed. Moreover, the increased vascular response to phenylephrine observed in the mesenteric bed is maintained by two mechanisms: an increased release of endothelial-derived vasoconstrictor prostanoids and a reduced modulatory action of endothelial NO, which seems to be associated with reduced post-transcriptional expression of eNOS.