917 resultados para non-communicable disease (NCD)


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To complement the existing treatment guidelines for all tumour types, ESMO organises consensus conferences to focus on specific issues in each type of tumour. The 2nd ESMO Consensus Conference on Lung Cancer was held on 11–12 May 2013 in Lugano. A total of 35 experts met to address several questions on non-small-cell lung cancer (NSCLC) in each of four areas: pathology and molecular biomarkers, first-line/second and further lines of treatment in advanced disease, early-stage disease and locally advanced disease. For each question, recommendations were made including reference to the grade of recommendation and level of evidence. This consensus paper focuses on locally advanced disease.

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Lung cancer accounts for more cancer-related deaths than any other cancer. In Finland, five-year survival ranges from 8% to 13%. The main risk factor for lung cancer is long-term cigarette smoking, but its carcinogenesis requires several other factors. The aim of the present study was to 1) evaluate post-operative quality of life, 2) compare clinical outcomes between minimally invasive and conventional open surgery, 3) evaluate the role of oxidative stress in the carcinogenesis of non-small lung cancer (NSCLC), and 4) to identify and characterise targeted agents for therapeutic and diagnostic use in surgery. For study I, pneumonectomy patients replied to 15D quality of life and baseline dyspnea questionnaires. Study III involved a prospective quality of life assessment using the 15D questionnaire after lobectomy or bi-lobectomy. Study IV was a retrospective comparison of clinical outcomes between 212 patients treated with open thoracotomy and 116 patients who underwent a minimally invasive technique. Study II measured parameters of oxidative metabolism (myeloperoxidase activity, glutathione content and NADPH oxidase activity) and DNA adducts. Study V employed the phage display method and identified a core motif for homing peptides. This method served in cell-binding, cell-localisation, and biodistribution studies. Following both pneumonectomy and lobectomy, NSCLC patients showed significantly decreased long-term quality of life. No significant correlation was noted between post-operative quality of life and pre-operative pulmonary function tests. Women suffered more from increased dyspnea after pneumonectomy which was absent after lobectomy or bi-lobectomy. Patients treated with video-assisted thoracoscopy showed significantly decreased morbidity and shorter periods of hospitalization than did open surgery patients. This improvement was achieved even though the VATS patients were older and suffered more comorbid conditions and poorer pulmonary function. No significant differences in survival were noted between these two groups. An increase in NADPH oxidase activity was noted in tumour samples of both adenocarcinoma and squamous cell carcinoma. This increase was independent from myeloperoxidase activity. Elevated glutathione content was noted in tumour tissue, especially in adenocarcinoma. After panning the clinical tumour samples with the phage display method, an amino acid sequence of ARRPKLD, the Thx, was chosen for further analysis. This method proved selective of tumour tissue in both in vitro and in vivo cell-binding assay, and biodistribution showed tumour accumulation. Because of the significantly reduced quality of life following pneumonectomy, other operative strategies should be implemented as an alternative (e.g. sleeve-lobectomy). To treat this disease, implementation of a minimally invasive surgical technique is safe, and the results showed decreased morbidity and a shorter period of hospitalisation than with thoracotomy. This technique may facilitate operative treatment of elderly patients with comorbid conditions who might otherwise be considered inoperable. Simultaneous exposure to oxidative stress and altered redox states indicates the important role of oxidative stress in the pathogenesis and malignant transformation of NSCLC. The studies showed with great specificity and with favourable biodistribution that Thx peptide is specific to NSCLC tumours. Thx thus shows promise in imaging, targeted therapy, and monitoring of treatment response.

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Celiac disease is life-long autoimmune disorder of the small intestine, which is caused by a reaction to gliadin found in wheat, rye and barley in genetically predisposed individuals. Proline- and glutamine -rich proteins cause villous atrophy and crypt hyperplasia with extensive inflammation in the epithelium and lamina propria. Symptoms of celiac disease vary considerably and elimination of gluten from diet is the only way to treat disease. In small intestine of celiac disease patient transglutaminase 2 (TG2) modifies gluten peptides, which causes T-cell activation and inflammation in the epithelium of mucosa. T-cell activation induces development of celiac disease specific antibodies. These celiac disease specific antibodies recognise TG2 and interfere in vitro and in vivo in angiogenesis. Abnormal angiogenesis is typical in many disorders, such in cancer, in which TG2 has a crucial role in the development and growth of tumor. Overexpression of TG2 has been shown to correlate with accelerated growth of tumor. TG2-specific antibodies are suggested to inhibit differentation of epithelial cell, increase their proliferation, decrease their barrier-function and increase the permeability of blood vessels. The aims of the pilot study were to establish whether celiac disease TG2 antibodies affect in vivo tumorigenesis and tumorangiogenesis as well as to try to clarify the mechanism behind the phenomenon. Tumor xenograft model was used in severe combined immunodeficient (SCID) mice. Human oesophageal carcinoma (OE-19) cancer cells were incubated with celiacs TG2 miniautoantibody (mini 2.8), non-celiac miniautoantibody (mini 6.2) or PBS before cancer cells were injected to mice subcutaneously. During the experiment mice were weighted and tumor size was measured couple of times per week. To estimate the volumes of tumors the following formula was used: π/6 * L* W* H. Experiment lasted for four weeks after which the mice were euthanized, cardiac blood and tissue samples taken and tumours were excised and weighted. Sections were made from tumors and immunohistochemical stainings were done to compare blood vessel areas and to study general tumors´morphology and other parameters. Western blot -analyse were performed to cancer cells. The masses and volumes were clearly smaller in mini 2.8-group compared to control groups and the necrotic area of tumor in mini 2.8 was smallest as percentage compared to control groups. Blood vessel area were smallest in mini 2.8 group. Results suggest that celiac disease anti-TG2-autoantibodies inhibit tumor growth, but the number of animals is insufficient to give an accurate outcome.

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Cassava brown streak disease (CBSD) was described for the first time in Tanganyika (now Tanzania) about seven decades ago. Tanganyika (now Tanzania) about seven decades ago. It was endemic in the lowland areas of East Africa and inland parts of Malawi and caused by Cassava brown streak virus (CBSV; genus Ipomovirus; Potyviridae). However, in 1990s CBSD was observed at high altitude areas in Uganda. The causes for spread to new locations were not known.The present work was thus initiated to generate information on genetic variability, clarify the taxonomy of the virus or viruses associated with CBSD in Eastern Africa as well as to understand the evolutionary forces acting on their genes. It also sought to develop a molecular based diagnostic tool for detection of CBSD-associated virus isolates. Comparison of the CP-encoding sequences of CBSD-associated virus isolates collected from Uganda and north-western Tanzania in 2007 and the partial sequences available in Genbank revealed occurrence of two genetically distinct groups of isolates. Two isolates were selected to represent the two groups. The complete genomes of isolates MLB3 (TZ:Mlb3:07) and Kor6 (TZ:Kor6:08) obtained from North-Western (Kagera) and North-Eastern (Tanga) Tanzania, respectively, were sequenced. The genomes were 9069 and 8995 nucleotides (nt), respectively. They translated into polyproteins that were predicted to yield ten mature proteins after cleavage. Nine proteins were typical in the family Potyviridae, namely P1, P3, 6K1, CI, 6K2, VPg, NIa-Pro, NIb and CP, but the viruses did not contain HC-Pro. Interestingly, genomes of both isolates contained a Maf/HAM1-like sequence (HAM1h; 678 nucleotides, 25 kDa) recombined between the NIb and CP domains in the 3’-proximal part of the genomes. HAM1h was also identified in Euphorbia ringspot virus (EuRSV) whose sequence was in GenBank. The HAM1 gene is widely spread in both prokaryotes and eukaryotes. In yeast (Saccharomyces cerevisiae) it is known to be a nucleoside triphosphate (NTP) pyrophosphatase. Novel information was obtained on the structural variation at the N-termini of polyproteins of viruses in the genus Ipomovirus. Cucumber vein yellowing virus (CVYV) and Squash vein yellowing virus (SqVYV) contain a duplicated P1 (P1a and P1b) but lack the HC-Pro. On the other hand, Sweet potato mild mottle virus (SPMMV), has a single but large P1 and has HC-Pro. Both virus isolates (TZ:Mlb3:07 & TZ:Kor6:08) characterized in this study contained a single P1 and lacked the HC-Pro which indicates unique evolution in the family Potyviridae. Comparison of 12 complete genomes of CBSD-associated viruses which included two genomes characterized in this study, revealed genetic identity of 69.0–70.3% (nt) and amino acid (aa) identities of 73.6–74.4% at polyprotein level. Comparison was also made among 68 complete CP sequences, which indicated 69.0-70.3 and 73.6-74.4 % identity at nt and aa levels, respectively. The genetic variation was large enough for dermacation of CBSD-associated virus isolates into two distinct species. The name CBSV was retained for isolates that were related to CBSV isolates available in database whereas the new virus described for the first time in this study was named Ugandan cassava brown streak virus (UCBSV) by the International Committee on Virus Taxonomy (ICTV). The isolates TZ:Mlb3:07 and TZ:Kor6:08 belong to UCBSV and CBSV, respectively. The isolates of CBSV and UCBSV were 79.3-95.5% and 86.3-99.3 % identitical at nt level, respectively, suggesting more variation amongst CBSV isolates. The main sources of variation in plant viruses are mutations and recombination. Signals for recombination events were detected in 50% of isolates of each virus. Recombination events were detected in coding and non-coding (3’-UTR) sequences except in the 5’UTR and P3. There was no evidence for recombination between isolates of CBSV and UCBSV. The non-synonomous (dN) to synonomous (dS) nucleotide substitution ratio (ω) for the HAM1h and CP domains of both viruses were ≤ 0.184 suggesting that most sites of these proteins were evolving under strong purifying selection. However, there were individual amino acid sites that were submitted to adaptive evolution. For instance, adaptive evolution was detected in the HAM1h of UCBSV (n=15) where 12 aa sites were under positive selection (P< 0.05) but not in CBSV (n=12). The CP of CBSV (n=23) contained 12 aa sites (p<0.01) while only 5 aa sites in the CP gene of UCBSV were predicted to be submitted to positive selection pressure (p<0.01). The advantages offered by the aa sites under positive selection could not be established but occurrence of such sites in the terminal ends of UCBSV-HAMIh, for example, was interpreted as a requirement for proteolysis during polyprotein processing. Two different primer pairs that simultaneously detect UCBSV and CBSV isolates were developed in this study. They were used successfully to study distribution of CBSV, UCBSV and their mixed infections in Tanzania and Uganda. It was established that the two viruses co-infect cassava and that incidences of co-infection could be as high as 50% around Lake Victoria on the Tanzanian side. Furthermore, it was revealed for the first time that both UCBSV and CBSV were widely distributed in Eastern Africa. The primer pair was also used to confirm infection in a close relative of cassava, Manihot glaziovii (Müller Arg.) with CBSV. DNA barcoding of M. glaziovii was done by sequencing the matK gene. Two out of seven M. glaziovii from the coastal areas of Korogwe and Kibaha in north eastern Tanzania were shown to be infected by CBSV but not UCBSV isolates. Detection in M. glaziovii has an implication in control and management of CBSD as it is likely to serve as virus reservoir. This study has contributed to the understanding of evolution of CBSV and UCBSV, which cause CBSD epidemic in Eastern Africa. The detection tools developed in this work will be useful in plant breeding, verification of the phytosanitary status of materials in regional and international movement of germplasm, and in all diagnostic activities related to management of CBSD. Whereas there are still many issues to be resolved such as the function and biological significance of HAM1h and its origin, this work has laid a foundation upon which the studies on these aspects can be based.

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Model building and molecular mechanics studies have been carried out to examine the potential structures for d(GGC/GCC)5 and d(CAG/CTG)5 that might relate to their biological function and association with triplet repeat expansion diseases. Model building studies suggested that hairpin and quadruplex structures could be formed with these repeat sequences. Molecular mechanics studies have demonstrated that the hairpin and hairpin dimmer structures of triplet repeat sequences formed by looping out of the two strands are as favourable as the corresponding B-DNA type hetero duplex structures. Further, at high salt condition, Greek key type quadruplex structures are energetically comparable with hairpin dimer and B-DNA type duplex structures. All tetrads in the quadruplex structures are well stacked and provide favourable stacking energy values. Interestingly, in the energy minimized hairpin dimer and Greek key type quadruplex structures, all the bases even in the non-G tetrads are cyclically hydrogen bonded, even though the A, C and T-tetrads were not hydrogen bonded in the starting structures.

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Chronic obstructive pulmonary disease (COPD) is a slowly progressive disease characterized by airway inflammation and largely irreversible airflow limitation. One major risk factor for COPD is cigarette smoking. Since the inflammatory process starts many years prior to the onset of clinical symptoms and still continues after smoking cessation, there is an urgent need to find simple non-invasive biomarkers that can be used in the early diagnosis of COPD and which could help in predicting the disease progression. The first aim of the present study was to evaluate the involvement of different oxidative/nitrosative stress markers, matrix metalloproteinases (MMPs) and their tissue inhibitor-1 (TIMP-1) in smokers and in COPD. Elevated numbers of inducible nitric oxide synthase (iNOS), nitrotyrosine, myeloperoxidase (MPO) and 4-hydroxy-2-nonenal (4-HNE) positive cells and increased levels of 8-isoprostane and lactoferrin were found in sputum of non-symptomatic smokers compared to non-smokers, and especially in subjects with stable mild to moderate COPD, and they correlated with the severity of airway obstruction. This suggests that an increased oxidant burden exists already in the airways of smokers with normal lung function values. However, none of these markers could differentiate healthy smokers from symptomatic smokers with normal lung function values i.e. those individuals who are at risk of developing COPD. In contrast what is known about asthma exhaled nitric oxide (FENO) was lower in smokers than in non-smokers, the reduced FENO value was significantly associated with neutrophilic inflammation and the elevated oxidant burden (positive cells for iNOS, nitrotyrosine and MPO). The levels of sputum MMP-8 and plasma MMP-12 appeared to differentiate subjects who have a risk for COPD development but these finding require further investigations. The levels of all studied MMPs correlated with the numbers of neutrophils, and MMP-8 and MMP-9 with markers of neutrophil activation (MPO, lactoferrin) suggesting that especially neutrophil derived oxidants may stimulate the tissue destructive MMPs already in lungs of smokers who are not yet experiencing any airflow limitation. When investigating the role of neutrophil proteases (neutrophil elastase, MMP-8, MMP-9) during COPD exacerbation and its recovery period, we found that levels of all these proteases were increased in sputum of patients with COPD exacerbation as compared to stable COPD and controls, and decreased during the one-month recovery period, giving evidence for a role of these enzymes in COPD exacerbations. In the last study, the effects of subject`s age and smoking habits were evaluated on the plasma levels of surfactant protein A (SP-A), SP-D, MMP-9 and TIMP-1. Long-term smoking increased the levels of all of these proteins. SP-A most clearly correlated with age, pack years and lung function decline (FEV1/FVC), and based on the receiver operating characteristic curve analysis, SP-A was the best marker for discriminating subjects with COPD from controls. In conclusion, these findings support the hypothesis that especially neutrophil derived oxidants may activate MMPs and induce an active remodeling process already in the lungs of smokers with normal lung function values. The marked increase of sputum levels of neutrophil proteases in smokers, stable COPD and/or during its exacerbations suggest that these enzymes play a role in the development and progression of COPD. Based on the comparison of various biomarkers, SP-A can be proposed to serve as sensitive biomarker in COPD development.

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Regular vaccinations with potent vaccine, in endemic countries and vaccination to live in non-endemic countries are the methods available to control foot-and-mouth disease. Selection of candidate vaccine strain is not only cumbersome but the candidate should grow well for high potency vaccine preparation. Alternative strategy is to generate an infectious cDNA of a cell culture-adapted virus and use the replicon for development of tailor-made vaccines. We produced a chimeric `O' virus in the backbone of Asia 1 and studied its characteristics. The chimeric virus showed high infectivity titre (>10(10)) in BHK 21 cell lines, revealed small plague morphology and there was no cross reactivity with antiserum against Asia I. The virus multiplies rapidly and reaches peak at 12 h post infection. The vaccine prepared with this virus elicited high antibody titres.

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Background: This study was performed to understand the possible therapeutic activity of Terminalia paniculata ethanolic extract (TPEE) on non alcoholic fatty liver in rats fed with high fat diet. Methods: Thirty six SD rats were divided into 6 groups (n = 6): Normal control (NC), high fat diet (HFD), remaining four groups were fed on HFD along with different doses of TPEE (100,150 and 200 mg/kg b.wt) or orlistat, for ten weeks. Liver tissue was homogenized and analyzed for lipid profiles, activities of superoxide dismutase (SOD), catalase (CAT) and malondialdehyde (MDA) content. Further, the expression levels of FAS and AMPK-1 alpha were also studied in addition to histopathology examination of liver tissue in all the groups. Results: HFD significantly increased hepatic liver total cholesterol (TC), triglycerides (TG), free fatty acids (FFA) and MDA but decreased the activities of SOD and CAT which were subsequently reversed by supplementation with TPEE in a dose-dependent manner. In addition, TPEE administration significantly down regulated hepatic mRNA expression of FAS but up regulated AMPK-1 alpha compared to HFD alone fed group. Furthermore, western blot analysis of FAS has clearly demonstrated decreased expression of FAS in HFD + TPEE (200 mg/kg b. wt) treated group when compared to HFD group at protein level. Conclusions: Our biochemical studies on hepatic lipid profiles and antioxidant enzyme activities supported by histological and expression studies suggest a potential therapeutic role for TPEE in regulating obesity through FAS.

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Background: We recently reported significant association of non-polio enteroviruses (NPEVs) with acute diarrhea in children. Persistent diarrhea (PD) remains a major cause of morbidity and mortality in infants below two years of age in developing countries. Understanding age-dependent frequency and duration of NPEV infections is important to determine their association with persistent diarrhea and disease burden. Objectives: A cohort of 140 infants was followed for 6 months to 2 years of age to determine the frequency, duration, and association with PD of NPEV infections in comparison with rotavirus and other agents. Study design: Stool samples were collected every 14 days, and diarrheal episodes and their duration were recorded. Enteroviruses were characterized by RT-PCR and VP1 gene sequence analysis, rotavirus by electropherotyping, and other agents by PCR. Results: Of 4545 samples, negative for oral polio vaccine strains, 3907 (85.96%) and 638 (14.04%) were NPEV-negative and NPEV-positive, respectively, representing 403 (8.87%) infection episodes. About 68% of NPEV infections occurred during the first year with every child having at least one episode lasting between four days and four months. Approximately 38% and 22% of total diarrheal episodes were positive for NPEV and RV, respectively. While about 18% of NPEV infection episodes were associated with diarrhea, 6% being persistent, 13% of total diarrheal episodes were persistent involving infections by monotype NPEV strains or sequential infections by multiple strains and other agents. Conclusions: This is the first report revealing NPEVs as the single most frequently and persistently detected viral pathogen in every PD episode. (C) 2014 Elsevier B.V. All rights reserved.

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T-protein, an aminomethyltransferase, represents one of the four components of glycine cleavage system (GCS) and catalyzes the transfer of methylene group from H-protein intermediate to tetrahydrofolate (THF) forming N-5, N-10-methylene THF (CH2-THF) with the release of ammonia. The malaria parasite genome encodes T-, H- and L-proteins, but not P-protein which is a glycine decarboxylase generating the aminomethylene group. A putative GCS has been considered to be functional in the parasite mitochondrion despite the absence of a detectable P-protein homologue. In the present study, the mitochondrial localization of T-protein in the malaria parasite was confirmed by immunofluorescence and its essentiality in the entire parasite life cycle was studied by targeting the T-protein locus in Plasmodium berghei (Pb). PbT knock out parasites did not show any growth defect in asexual, sexual and liver stages indicating that the T-protein is dispensable for parasite survival in vertebrate and invertebrate hosts. The absence of P-protein homologue and the non-essentiality of T protein suggest the possible redundancy of GCS activity in the malaria parasite. Nevertheless, the H- and L-proteins of GCS could be essential for malaria parasite because of their involvement in alpha-lcetoacid dehydrogenase reactions. (C) 2014 Elsevier B.V. All rights reserved.

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Ser/Thr and Tyr protein kinases orchestrate many signalling pathways and hence loss in this balance leads to many disease phenotypes. Due to their high abundance, diversity and importance, efforts have been made in the past to classify kinases and annotate their functions at both gross and fine levels. These kinases are conventionally classified into subfamilies based on the sequences of catalytic domains. Usually the domain architecture of a full-length kinase is consistent with the subfamily classification made based on the sequence of kinase domain. Important contributions of modular domains to the overall function of the kinase are well known. Recently occurrence of two kinds of outlier kinases-''Hybrid'' and ``Rogue'' has been reported. These show considerable deviations in their domain architectures from the typical domain architecture known for the classical kinase subfamilies. This article provides an overview of the different subfamilies of human kinases and the role of non-kinase domains in functions and diseases. Importantly this article provides analysis of hybrid and rogue kinases encoded in the human genome and highlights their conservation in closely related primate species. These kinases are examples of elegant rewiring to bring about subtle functional differences compared to canonical variants.

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We have recently reported significant association of non-polio enteroviruses (NPEVs) with acute and persistent diarrhea (18-21% of total diarrheal cases), and non-diarrheal Increased Frequency of Bowel Movements (IFoBM-ND) (about 29% of the NPEV infections) in children and that the NPEV-associated diarrhea was as significant as rotavirus diarrhea. However, their diarrhea-causing potential is yet to be demonstrated in an animal model system. Since the determination of virus titers by the traditional plaque assay takes 4-7 days, there is a need for development of a rapid method for virus titer determination to facilitate active clinical research on enterovirus-associated diarrhea. The goal of this study is to develop a cell-based rapid detection and enumeration method and to demonstrate the diarrhea-inducing potential of purified and characterized non-polio enteroviruses, which were isolated from diarrheic children. Here we describe generation of monoclonal and polyclonal antibodies against purified strains belonging to different serotypes, and development of an enzyme-linked immuno focus assay (ELIFA) for detection and enumeration of live NPEV particles in clinical and purified virus samples, and a newborn mouse model for NPEV diarrhea. Plaque-purified NPVEs, belonging to different serotypes, isolated from children with diarrhea, were grown in cell culture and purified by isopycnic CsCl density gradient centrifugation. By ELIFA, NPEVs could be detected and enumerated within 12 h post-infection. Our results demonstrated that Coxsackievirus B1 (CVB1) and CVB5 strains, isolated from diarrheic children, induced severe diarrhea in orally-inoculated 9-12 day-old mouse pups, fulfilling Koch's postulates. The methods described here would facilitate studies on NPEV-associated gastrointestinal disease. (C) 2015 Elsevier B.V. All rights reserved.

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Background: Dicistroviridae is a new family of small, non-enveloped, +ssRNA viruses pathogenic to both beneficial arthropods and insect pests. Little is known about the dicistrovirus replication mechanism or gene function, and any knowledge on these subjects comes mainly from comparisons with mammalian viruses from the Picornaviridae family. Due to its peculiar genome organization and characteristics of the per os viral transmission route, dicistroviruses make good candidates for use as biopesticides. Triatoma virus (TrV) is a pathogen of Triatoma infestans (Hemiptera: Reduviidae), one of the main vectors of the human trypanosomiasis disease called Chagas disease. TrV was postulated as a potential control agent against Chagas' vectors. Although there is no evidence that TrV nor other dicistroviruses replicate in species outside the Insecta class, the innocuousness of these viruses in humans and animals needs to be ascertained. Methods: In this study, RT-PCR and ELISA were used to detect the infectivity of this virus in Mus musculus BALB/c mice. Results: In this study we have observed that there is no significant difference in the ratio IgG2a/IgG1 in sera from animals inoculated with TrV when compared with non-inoculated animals or mice inoculated only with non-infective TrV protein capsids. Conclusions: We conclude that, under our experimental conditions, TrV is unable to replicate inmice. This study constitutes the first test to evaluate the infectivity of a dicistrovirus in a vertebrate animal model.

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The EC (entorhinal cortex) is fundamental for cognitive and mnesic functions. Thus damage to this area appears as a key element in the progression of AD (Alzheimer's disease), resulting in memory deficits arising from neuronal and synaptic alterations as well as glial malfunction. In this paper, we have performed an in-depth analysis of astroglial morphology in the EC by measuring the surface and volume of the GFAP (glial fibrillary acidic protein) profiles in a triple transgenic mouse model of AD [3xTg-AD (triple transgenic mice of AD)]. We found significant reduction in both the surface and volume of GFAP-labelled profiles in 3xTg-AD animals from very early ages (1 month) when compared with non-Tg (non-transgenic) controls (48 and 54%, reduction respectively), which was sustained for up to 12 months (33 and 45% reduction respectively). The appearance of Lambda beta (amyloid beta-peptide) depositions at 12 months of age did not trigger astroglial hypertrophy; nor did it result in the close association of astrocytes with senile plaques. Our results suggest that the AD progressive cognitive deterioration can be associated with an early reduction of astrocytic arborization and shrinkage of the astroglial domain, which may affect synaptic connectivity within the EC and between the EC and other brain regions. In addition, the EC seems to be particularly vulnerable to AD pathology because of the absence of evident astrogliosis in response to A beta accumulation. Thus we can consider that targeting astroglial atrophy may represent a therapeutic strategy which might slow down the progression of AD.