908 resultados para misfolding and disease


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Gardnerella vaginalis is the most frequent microorganism found in bacterial vaginosis (BV), while Escherichia coli and Enterococcus faecalis are amongst the most frequent pathogens found in urinary tract infections (UTIs). This study aimed to evaluate possible interactions between UTIs pathogens and G. vaginalis using an in vitro dual-species biofilm model. Our results showed that dual-species biofilms reached significantly higher bacterial concentration than mono-species biofilms. Moreover, visualization of dual-populations species in the biofilms, using the epifluorescence microscopy, revealed that all of the urogenital pathogens co-existed with G. vaginalis. In conclusion, our work demonstrates that uropathogens can incorporate into mature BV biofilms.

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Renal cell tumors (RCTs) are the most lethal of the common urological cancers. The widespread use of imaging entailed an increased detection of small renal masses, emphasizing the need for accurate distinction between benign and malignant RCTs, which is critical for adequate therapeutic management. Histone methylation has been implicated in renal tumorigenesis, but its potential clinical value as RCT biomarker remains mostly unexplored. Hence, the main goal of this study was to identify differentially expressed histone methyltransferases (HMTs) and histone demethylases (HDMs) that might prove useful for RCT diagnosis and prognostication, emphasizing the discrimination between oncocytoma (a benign tumor) and renal cell carcinoma (RCC), especially the chromophobe subtype (chRCC). We found that the expression levels of three genes-SMYD2, SETD3, and NO66-was significantly altered in a set of RCTs, which was further validated in a large independent cohort. Higher expression levels were found in RCTs compared to normal renal tissues (RNTs) and in chRCCs comparatively to oncocytomas. SMYD2 and SETD3 mRNA levels correlated with protein expression assessed by immunohistochemistry. SMYD2 transcript levels discriminated RCTs from RNT, with 82.1% sensitivity and 100% specificity (AUC=0.959), and distinguished chRCCs from oncocytomas, with 71.0% sensitivity and 73.3% specificity (AUC: 0.784). Low expression levels of SMYD2, SETD3, and NO66 were significantly associated with shorter disease-specific and disease-free survival, especially in patients with non-organ confined tumors. We conclude that expression of selected HMTs and HDMs might constitute novel biomarkers to assist in RCT diagnosis and assessment of tumor aggressiveness.

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Empirical evidence supports the hypothesis that emotional states might contribute to cardiovascular disease and health through multiple pathways. To the extent that the acute cardiovascular response to emotional events plays a role in cardiovascular health and disease, an essential step in order to understand this possible link is to define the hemodynamic response to affective challenges. This was the aim of the present study. We assessed blood pressure (BP), heart rate (HR), stroke volume (SV), cardiac output, and total peripheral resistance (TPR) in response to 13 picture series in 18 men and 19 women (mean age 26) in order to investigate their hemodynamic responses associated with activation of the appetitive and defensive motivational systems underlying emotional experience. The hemodynamic parameters were recorded by finger-cuff photoplethysmography with Finometer™ (FMS Finapres Medical Systems, Amsterdam) and electrocardiography with the Lifeshirt system (VivoMetrics Inc., Ventura, California). Participants rated self-perceived pleasantness and arousal for each series. In men, BP and SV, but not TPR, increased with increasing self-rated arousal both for appetitive and defensive activation, whereas in women these relationships were almost absent, especially, for defensive activation. HR decelerated more in response to negative than positive and neutral pictures, and more so in men than women. These findings indicate striking sex differences. In particular, it is suggested that the sympathetic inotropic effect to the heart increases with increasing self-rated arousal strongly in men but only weakly in women. Regardless of sex differences, the modulation of the cardiovascular response to affective pictures along the dimensions of pleasantness and arousal is primarily myocardial, and the pattern of cardiovascular response is consistent with a configuration of cardiac sympathetic-parasympathetic coactivation. One possible implication of the observed sex differences concerns the link between affective states and cardiovascular health and disease. Men have a higher incidence of cardiovascular diseases than premenopausal women, and exaggerated sympathetic reactivity to emotional events is a potential pathophysiological mechanism. These findings extend current knowledge showing that under several acute behavioral challenges men demonstrate stronger cardiovascular reactivity than women.

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The peripheral nervous system (PNS) is involved in many age-dependent neurological deficits, including numbness, pain, restless legs, trouble with walking and balance that are commonly found in the elderly. These symptoms generally result from demyelination and/or loss of axonal integrity. However, the precise identity of age-regulated molecular changes in either neuronal or glial compartments of the nerve is unclear. Interestingly, these deficiencies are also present in inherited neuropathies, where the expressivity of the rapid and early onset phenotypes is undeniably more severe than in normal aging. Nevertheless, especially the molecular changes underlying loss of axonal integrity in neuropathy condition are also poorly understood. To unravel molecular mechanisms affected by PNS aging, we used wildtype mice at 17 time-points from day of birth until senescence (28 months-old). For the neuropathy study, we focused on 56 day-old Schwann cell-specific neuropathy-inducing mutants, MPZCre/1/ LpinfE2-3/fE2-3 and MPZCre/1/ScapfE1/fE1 mice, that have, at this age, already developed neuropathic symptoms. Transcriptomes of dissected Schwann cell-containing endoneurium or sensory neuron-containing dorsal root ganglia have been analyzed throughout time or genotypes, using Illumina Bead Chips. Following data validation, we identified groups of differentially expressed genes in the development, aging and in the neuropathic mutants, in both glial and neuronal compartments. We detected substantial differences in the dynamics of changes in gene expression during development and aging between these two compartments. Furthermore, considering the above-mentioned phenotypic similarities, we integrated aging and mutant data. Interestingly, we observed that there are some parallels at the molecular level between processes involved in aging, which leads to less severe and more progressive PNS alterations, and in the rapid onset peripheral neuropathies. Apart from helping the understanding of molecular alterations underlying age-related PNS phenotypes, this data should also contribute to the identification of pathways that could be used as targets for therapeutical approaches to prevent complications associated with both aging and inherited forms of neuropathies.

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A panel of novel monoclonal antibodies was tested on the human entorhinal cortex for the recognition of age- and disease-related changes of neurofilament proteins (NF). Several antibodies identified phosphorylated NF-H subunit, which occurred preferentially in those aged between 60 and 80 years and were localized in degenerating neurons. Such neurons also contained neurofibrillary tangles, but neurofilament aggregates did not co-localize with tangles, nor did the quantity nor the number of NF-positive neurons correlate with the severity of Alzheimer's disease. This points to a susceptibility of NF in a subset of neurons for phosphorylation- and metabolically related morphological changes during neurodegeneration.

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The association between both HLA-A1 and B5 antigens and chronic forms of human schistosomiasis was studied in 64 patients and 26 normal controls from a southern Brazilian hospital. No apparent correlation between the chronic forms of the disease and the expression of those antigens was detected. However, the analysis of these date together with those observed on an Egyptian sample suggests that the presence of either of the antigens and the hepatomegalic forms of schistosomiasis is significant, without heterogeneity. Converseley, the association of histocompatibility antigens with splenogegaly is consistent and significant only for HLA-B5, but not HLA-A1

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ABSTRACT Objectives: Patients with failed back surgery syndrome (FBSS) and chronic neuropathic pain experience levels of health-related quality of life (HRQoL) that are considerably lower than those reported in other areas of chronic pain. The aim of this article was to quantify the extent to which reductions in (leg and back) pain and disability over time translate into improvements in generic HRQoL as measured by the EuroQoL-5D and SF-36 instruments. Methods: Using data from the multinational Prospective, Randomized, Controlled, Multicenter Study of Patients with Failed Back Surgery Syndrome trial, we explore the relationship between generic HRQoL-assessed using two instruments often used in clinical trials (i.e., the SF-36 and EuroQol-5D)-and disease-specific outcome measures (i.e., Oswestry disability index [ODI], leg and back pain visual analog scale [VAS]) in neuropathic patients with FBSS. Results: In our sample of 100 FBSS patients, generic HRQoL was moderately associated with ODI (correlation coefficient: -0.462 to -0.638) and mildly associated with leg pain VAS (correlation coefficient: -0.165 to -0.436). The multilevel regression analysis results indicate that functional ability (as measured by the ODI) is significantly associated with HRQoL, regardless of the generic HRQoL instrument used. On the other hand, changes over time in leg pain were significantly associated with changes in the EuroQoL-5D and physical component summary scores, but not with the mental component summary score. Conclusions: Reduction in leg pain and functional disability is statistically significantly associated with improvements in generic HRQoL. This is the first study to investigate the longitudinal relationship between generic and disease-specific HRQoL of neuropathic pain patients with FBSS, using multinational data.

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Despite advances in the diagnosisand treatment of head and neck cancer,survival rates have not improvedover recent years. New therapeuticstrategies, including immunotherapy,are the subject of extensive research.In several types of tumors, the presenceof tumor infiltrating lymphocytes(TILs), notably CD8+ T cellsand dendritic cells, has been correlatedwith improved prognosis. Moreover,some T cells among TILs havebeen shown to kill tumor cells in vitroupon recognition of tumor-associatedantigens. Tumor associated antigensare expressed in a significant proportionof squamous cell carcinoma ofthe head and neck and apparently mayplay a role in the regulation of cancercell growth notably by inhibition ofp53 protein function in some cancers.The MAGE family CT antigens couldtherefore potentially be used as definedtargets for immunotherapy andtheir study bring new insight in tumorgrowth regulation mechanisms. Between1995 - 2005 54 patients weretreated surgically in our institution forsquamous cell carcinoma of the oralcavity. Patient and clinical data wasobtained from patient files and collectedinto a computerized database.For each patient, paraffin embeddedtumor specimens were retrieved andexpression of MAGE CT antigens,p53, NY-OESO-1 were analyzed byimmunohistochemistry. Results werethen correlated with histopathologicalparameter such as tumor depth,front invasion according to Bryne andboth, local control and disease freesurvival. MAGE-A was expressed in52% of patients. NY-ESO-1 and p53expression was found in 7% and 52%cases respectively. A higher tumordepth was significantly correlatedwith expression of MAGE-Aproteins(p = 0.03). No significant correlationcould be made between the expressionof both p53 andNY-OESO-1 andhistopathological parameters. Expressionof tumor-associated antigendid not seem to impact significantlyon patient prognosis. As does thedemonstration of p53 function inhibitionby CT antigens of MAGE family,our results suggest, that tumor associatedantigens may be implicated in tumorprogression mechanisms. Thishypothesis need further investigationto clarify the relationship betweenhost immune response and local tumorbiology.

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Altered synaptic function is considered one of the first features of Alzheimer disease (AD). Currently, no treatment is available to prevent the dysfunction of excitatory synapses in AD. Identification of the key modulators of synaptopathy is of particular significance in the treatment of AD. We here characterized the pathways leading to synaptopathy in TgCRND8 mice and showed that c-Jun N-terminal kinase (JNK) is activated at the spine prior to the onset of cognitive impairment. The specific inhibition of JNK, with its specific inhibiting peptide D-JNKI1, prevented synaptic dysfunction in TgCRND8 mice. D-JNKI1 avoided both the loss of postsynaptic proteins and glutamate receptors from the postsynaptic density and the reduction in size of excitatory synapses, reverting their dysfunction. This set of data reveals that JNK is a key signaling pathway in AD synaptic injury and that its specific inhibition offers an innovative therapeutic strategy to prevent spine degeneration in AD.

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Eosinophilic esophagitis (EoE) is a clinicopathologic condition of increasing recognition and prevalence. In 2007, a consensus recommendation provided clinical and histopathologic guidance for the diagnosis and treatment of EoE; however, only a minority of physicians use the 2007 guidelines, which require fulfillment of both histologic and clinical features. Since 2007, the number of EoE publications has doubled, providing new disease insight. Accordingly, a panel of 33 physicians with expertise in pediatric and adult allergy/immunology, gastroenterology, and pathology conducted a systematic review of the EoE literature (since September 2006) using electronic databases. Based on the literature review and expertise of the panel, information and recommendations were provided in each of the following areas of EoE: diagnostics, genetics, allergy testing, therapeutics, and disease complications. Because accumulating animal and human data have provided evidence that EoE appears to be an antigen-driven immunologic process that involves multiple pathogenic pathways, a new conceptual definition is proposed highlighting that EoE represents a chronic, immune/antigen-mediated disease characterized clinically by symptoms related to esophageal dysfunction and histologically by eosinophil-predominant inflammation. The diagnostic guidelines continue to define EoE as an isolated chronic disorder of the esophagus diagnosed by the need of both clinical and pathologic features. Patients commonly have high rates of concurrent allergic diatheses, especially food sensitization, compared with the general population. Proved therapeutic options include chronic dietary elimination, topical corticosteroids, and esophageal dilation. Important additions since 2007 include genetic underpinnings that implicate EoE susceptibility caused by polymorphisms in the thymic stromal lymphopoietin protein gene and the description of a new potential disease phenotype, proton pump inhibitor-responsive esophageal eosinophila. Further advances and controversies regarding diagnostic methods, surrogate disease markers, allergy testing, and treatment approaches are discussed.

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The kinetoplastid membrane protein 11 (KMP-11) has been recently described in Leishmania (Leishmania) donovani as a major component of the promastigote membrane. Two oligonucleotide primers were synthesized to PCR-amplify the entire coding region of New World Leishmania species. The Leishmania (Viannia) panamensis amplification product was cloned, sequenced and the putative amino acid sequence determined. A remarkably high degree of sequence homology was observed with the corresponding molecule of L. (L) donovani and L. (L) infantum (97% and 96%, respectively). Southern blot analysis showed that the KMP-11 locus is conformed by three copies of the gene. The L. (V) panamensis ORF was subsequently cloned in a high expression vector and the recombinant protein was induced and purified from Escherichia coli cultures. Immunoblot analysis showed that 80%, 77% and 100% sera from cutaneous, mucocutaneous and visceral leishmaniasis patients, respectively, recognized the recombinant KMP-11 protein. In a similar assay, 86% of asymptomatic Leishmania-infected individuals showed IgG antibodies against the rKMP-11. We propose that KMP-11 could be used as a serologic marker for infection and disease caused by Leishmania in America.

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In several studies reporting cell death (CD) in lower eukaryotes and in the human protozoan parasite Leishmania, proteolytic activity was revealed using pan-caspase substrates or inhibitors such as carbobenzoxy-valyl-alanyl-aspartyl-[O-methyl]-fluoromethylketone (Z-VAD-FMK). However, most of the lower eukaryotes do not encode caspase(s) but MCA, which differs from caspase(s) in its substrate specificity and cannot be accountable for the recognition of Z-VAD-FMK. In the present study, we were interested in identifying which enzyme was capturing the Z-VAD substrate. We show that heat shock (HS) induces Leishmania CD and leads to the intracellular binding of Z-VAD-FMK. We excluded binding and inhibition of Z-VAD-FMK to Leishmania major metacaspase (LmjMCA), and identified cysteine proteinase C (LmjCPC), a cathepsin B-like (CPC) enzyme, as the Z-VAD-FMK binding enzyme. We confirmed the specific interaction of Z-VAD-FMK with CPC by showing that Z-VAD binding is absent in a Leishmania mexicana strain in which the cpc gene was deleted. We also show that parasites exposed to various stress conditions release CPC into a soluble fraction. Finally, we confirmed the role of CPC in Leishmania CD by showing that, when exposed to the oxidizing agent hydrogen peroxide (H(2)O(2)), cpc knockout parasites survived better than wild-type parasites (WT). In conclusion, this study identified CPC as the substrate of Z-VAD-FMK in Leishmania and as a potential additional executioner protease in the CD cascade of Leishmania and possibly in other lower eukaryotes.

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Background and purpose: Decision making (DM) has been defined as the process through which a person forms preferences, selects and executes actions, and evaluates the outcome related to a selected choice. This ability represents an important factor for adequate behaviour in everyday life. DM impairment in multiple sclerosis (MS) has been previously reported. The purpose of the present study was to assess DM in patients with MS at the earliest clinically detectable time point of the disease. Methods: Patients with definite (n=109) or possible (clinically isolated syndrome, CIS; n=56) MS, a short disease duration (mean 2.3 years) and a minor neurological disability (mean EDSS 1.8) were compared to 50 healthy controls aged 18 to 60 years (mean age 32.2) using the Iowa Gambling Task (IGT). Subjects had to select a card from any of 4 decks (A/B [disadvantageous]; C/D [advantageous]). The game consisted of 100 trials then grouped in blocks of 20 cards for data analysis. Skill in DM was assessed by means of a learning index (LI) defined as the difference between the averaged last three block indexes and first two block indexes (LI=[(BI-3+BI-4+BI-5)/3-(BI-1+B2)/2]). Non parametric tests were used for statistical analysis. Results: LI was higher in the control group (0.24, SD 0.44) than in the MS group (0.21, SD 0.38), however without reaching statistical significance (p=0.7). Interesting differences were detected when MS patients were grouped according to phenotype. A trend to a difference between MS subgroups and controls was observed for LI (p=0.06), which became significant between MS subgroups (p=0.03). CIS patients who confirmed MS diagnosis by presenting a second relapse after study entry showed a dysfunction in the IGT in comparison to the other CIS (p=0.01) and definite MS (p=0.04) patients. In the opposite, CIS patients characterised by not entirely fulfilled McDonald criteria at inclusion and absence of relapse during the study showed an normal learning pattern on the IGT. Finally, comparing MS patients who developed relapses after study entry, those who remained clinically stable and controls, we observed impaired performances only in relapsing patients in comparison to stable patients (p=0.008) and controls (p=0.03). Discussion: These results raise the assumption of a sustained role for both MS relapsing activity and disease heterogeneity (i.e. infra-clinical severity or activity of MS) in the impaired process of decision making.

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Triggering receptor expressed on myeloid cells-1 (TREM-1) is a potent amplifier of pro-inflammatory innate immune reactions. While TREM-1-amplified responses likely aid an improved detection and elimination of pathogens, excessive production of cytokines and oxygen radicals can also severely harm the host. Studies addressing the pathogenic role of TREM-1 during endotoxin-induced shock or microbial sepsis have so far mostly relied on the administration of TREM-1 fusion proteins or peptides representing part of the extracellular domain of TREM-1. However, binding of these agents to the yet unidentified TREM-1 ligand could also impact signaling through alternative receptors. More importantly, controversial results have been obtained regarding the requirement of TREM-1 for microbial control. To unambiguously investigate the role of TREM-1 in homeostasis and disease, we have generated mice deficient in Trem1. Trem1(-/-) mice are viable, fertile and show no altered hematopoietic compartment. In CD4(+) T cell- and dextran sodium sulfate-induced models of colitis, Trem1(-/-) mice displayed significantly attenuated disease that was associated with reduced inflammatory infiltrates and diminished expression of pro-inflammatory cytokines. Trem1(-/-) mice also exhibited reduced neutrophilic infiltration and decreased lesion size upon infection with Leishmania major. Furthermore, reduced morbidity was observed for influenza virus-infected Trem1(-/-) mice. Importantly, while immune-associated pathologies were significantly reduced, Trem1(-/-) mice were equally capable of controlling infections with L. major, influenza virus, but also Legionella pneumophila as Trem1(+/+) controls. Our results not only demonstrate an unanticipated pathogenic impact of TREM-1 during a viral and parasitic infection, but also indicate that therapeutic blocking of TREM-1 in distinct inflammatory disorders holds considerable promise by blunting excessive inflammation while preserving the capacity for microbial control.

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A review of the ticks (Acari, Ixodida) of the State of Rio Grande do Sul, southern Brazil, was completed as a step towards a definitive list (currently indicated as 12) of such species, their hosts and distribution. The ticks: Argas miniatus (poultry), Ixodes loricatus (opossums), Amblyomma aureolatum (dogs), A. calcaratum (anteaters), A. cooperi (capybaras), A. nodosum (anteaters), A. tigrinum (dogs) (Neotropical) and Rhipicephalus sanguineus (dogs) (introduced, cosmopolitan, Afrotropical) were confirmed as present, in addition to the predominant, Boophilus microplus (cattle) (introduced, pan-tropical, Oriental). Of the further 18 species thus far reported in the literature as present in the state, but unavailable for examination: only Ornithodoros brasiliensis (humans and their habitations) (Neotropical), Ixodes affinis (deer) (Nearctic/Neotropical) and I. auritulus (birds) (Nearctic/Neotropical/Afrotropical/ Australasian) are considered likely; 13 species would benefit from corroborative local data but the majority appear unlikely; reports of A. maculatum (Nearctic/Neotropical, but circum-Caribbean) are considered erroneous; the validity of A. fuscum is in doubt. The very recent, first known report of the tropical Anocentor nitens (horses)(Nearctic/Neotropical), but still apparent absence of the tropical A. cajennense (catholic) (Nearctic/Neotropical) and the sub-tropical/temperate Ixodes pararicinus (cattle) (Neotropical) in Rio Grande do Sul are important for considerations on their current biogeographical distribution and its dynamics in South America. The state has relatively long established, introduced ("exotic"), Old World tick species (B. microplus, R. sanguineus) that continue to represent significant pests and disease vectors to their traditional, introduced domestic animal hosts, cattle and urban dogs. There are also indigenous, New World ticks (A. miniatus, O. brasiliensis, A. aureolatum, A. nitens), as both long established and possibly newly locally introduced species in the state, that should be considered as potential and emergent pests and pathogen vectors to humans and their more recently acquired, introduced domestic animal hosts; rural poultry, dogs and horses.