993 resultados para retrovirus, integration site


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In this paper, we consider the ATM networks in which the virtual path concept is implemented. The question of how to multiplex two or more diverse traffic classes while providing different quality of service requirements is a very complicated open problem. Two distinct options are available: integration and segregation. In an integration approach all the traffic from different connections are multiplexed onto one VP. This implies that the most restrictive QOS requirements must be applied to all services. Therefore, link utilization will be decreased because unnecessarily stringent QOS is provided to all connections. With the segregation approach the problem can be much simplified if different types of traffic are separated by assigning a VP with dedicated resources (buffers and links). Therefore, resources may not be efficiently utilized because no sharing of bandwidth can take place across the VP. The probability that the bandwidth required by the accepted connections exceeds the capacity of the link is evaluated with the probability of congestion (PC). Since the PC can be expressed as the CLP, we shall simply carry out bandwidth allocation using the PC. We first focus on the influence of some parameters (CLP, bit rate and burstiness) on the capacity required by a VP supporting a single traffic class using the new convolution approach. Numerical results are presented both to compare the required capacity and to observe which conditions under each approach are preferred

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BACKGROUND: Mediastinal lymph-node dissection was compared to systematic mediastinal lymph-node sampling in patients undergoing complete resection for non-small cell lung cancer with respect to morbidity, duration of chest tube drainage and hospitalization, survival, disease-free survival, and site of recurrence. METHODS: A consecutive series of one hundred patients with non-small-cell lung cancer, clinical stage T1-3 N0-1 after standardized staging, was divided into two groups of 50 patients each, according to the technique of intraoperative mediastinal lymph-node assessment (dissection versus sampling). Mediastinal lymph-node dissection consisted of removal of all lymphatic tissues within defined anatomic landmarks of stations 2-4 and 7-9 on the right side, and stations 4-9 on the left side according to the classification of the American Thoracic Society. Systematic mediastinal lymph-node sampling consisted of harvesting of one or more representative lymph nodes from stations 2-4 and 7-9 on the right side, and stations 4-9 on the left side. RESULTS: All patients had complete resection. A mean follow-up time of 89 months was achieved in 92 patients. The two groups of patients were comparable with respect to age, gender, performance status, tumor stage, histology, extent of lung resection, and follow-up time. No significant difference was found between both groups regarding the duration of chest tube drainage, hospitalization, and morbidity. However, dissection required a longer operation time than sampling (179 +/- 38 min versus 149 +/- 37 min, p < 0.001). There was no significant difference in overall survival between the two groups; however, patients with stage I disease had a significantly longer disease-free survival after dissection than after sampling (60.2 +/- 7 versus 44.8 +/- 8 months, p < 0.03). Local recurrence was significantly higher after sampling than after dissection in patients with stage I tumor (12.5% versus 45%, p = 0.02) and in patients with nodal tumor negative mediastinum (N0/N1 disease) (46% versus 13%, p = 0.004). CONCLUSION: Our results suggest that mediastinal lymph-node dissection may provide a longer disease-free survival in stage I non-small cell lung cancer and, most importantly, a better local tumor control than mediastinal lymph-node sampling after complete resection for N0/N1 disease without leading to increased morbidity.

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BACKGROUND: Surveillance is an essential element of surgical site infection (SSI) prevention. Few studies have evaluated the long-term effect of these programmes. AIM: To present data from a 13-year multicentre SSI surveillance programme from western and southern Switzerland. METHODS: Surveillance with post-discharge follow-up was performed according to the US National Nosocomial Infections Surveillance (NNIS) system methods. SSI rates were calculated for each surveyed type of surgery, overall and by year of participation in the programme. Risk factors for SSI and the effect of surveillance time on SSI rates were analysed by multiple logistic regression. FINDINGS: Overall SSI rates were 18.2% after 7411 colectomies, 6.4% after 6383 appendicectomies, 2.3% after 7411 cholecystectomies, 1.7% after 9933 herniorrhaphies, 1.6% after 6341 hip arthroplasties, and 1.3% after 3667 knee arthroplasties. The frequency of SSI detected after discharge varied between 21% for colectomy and 94% for knee arthroplasty. Independent risk factors for SSI differed between operations. The NNIS risk index was predictive of SSI in gastrointestinal surgery only. Laparoscopic technique was protective overall, but associated with higher rates of organ-space infections after appendicectomy. The duration of participation in the surveillance programme was not associated with a decreased SSI rate for any of the included procedure. CONCLUSION: These data confirm the effect of post-discharge surveillance on SSI rates and the protective effect of laparoscopy. There is a need to establish alternative case-mix adjustment methods. In contrast to other European programmes, no positive impact of surveillance duration on SSI rates was observed.

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This paper presents the use of a mobile robot platform as an innovative educational tool in order to promote and integrate different curriculum knowledge. Hence, it is presented the acquired experience within a summer course named ldquoapplied mobile roboticsrdquo. The main aim of the course is to integrate different subjects as electronics, programming, architecture, perception systems, communications, control and trajectory planning by using the educational open mobile robot platform PRIM. The summer course is addressed to a wide range of student profiles. However, it is of special interests to the students of electrical and computer engineering around their final academic year. The summer course consists of the theoretical and laboratory sessions, related to the following topics: design & programming of electronic devices, modelling and control systems, trajectory planning and control, and computer vision systems. Therefore, the clues for achieving a renewed path of progress in robotics are the integration of several knowledgeable fields, such as computing, communications, and control sciences, in order to perform a higher level reasoning and use decision tools with strong theoretical base

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L’estudi de l’Anàlisi del Cicle de Vida (ACV) ha estat realitzat a l’empresa CRODA Ibèrica S.A - Mevisa Site, en concret a la línia productiva on s’hi fabrica el monoestearat de glicerina utilitzant una eina informàtica comercial denominada SIMAPRO que analitza i compara els aspectes mediambientals d’un producte d’una manera sistemàtica i consistent seguint les recomanacions de les normes ISO 14040

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The prototypic arenavirus lymphocytic choriomeningitis virus (LCMV), which naturally persists in rodents, represents a model for HIV, HBV, and HCV. Cleavage of the viral glycoprotein precursor by membrane-bound transcription factor peptidase, site 1 (Mbtps1 or site-1 protease), is crucial for the life cycle of arenaviruses and therefore represents a potential target for therapy. Recently, we reported a viable hypomorphic allele of Mbtps1 (woodrat) encoding a protease with diminished enzymatic activity. Using the woodrat allele, we examine the role of Mbtps1 during persistent LCMV infection. Surprisingly, Mbtps1 inhibition limits persistent but not acute viral infection and is associated with an organ/cell type-specific decrease in viral titers. Analysis of bone marrow-derived dendritic cells from woodrat mice supports their specific role in resolving persistent viral infection. These results support in vivo targeting of Mbtps1 in the treatment of arenavirus infections and demonstrate a critical role for dendritic cells in persistent viral infections.

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We describe a new rapid and efficient polymerase chain reaction (PCR)-based site-directed mutagenesis method. This procedure is effective with any plasmid and it employs four oligonucleotide primers. One primer contains the desired mutation, the second is oriented in the opposite direction (one of these two primers should be phosphorylated), and the third and fourth should be coding in complementary fashion for a unique restriction site to be introduced in a nonessential region. The method consists of two simultaneous PCR reactions; the PCR products are digested with the enzyme that recognizes the newly introduced unique restriction site and then ligased and used to transform competent bacteria. Additionally, the use of Dpn I facilitates the elimination of template DNA. The newly introduced restriction site is essential for ligation in the correct orientation of the two-PCR products and is further used for mutant screening. Resulting plasmids carry both the new restriction site and the desired mutation. Using this method, more than 20 mutants have already been generated (using two different kinds of templates); all these mutants were sequenced for the desired mutation and transfected into AtT-20 cells and the expressed mutant proteins encoded by the vector were assayed.

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Access to online repositories for genomic and associated "-omics" datasets is now an essential part of everyday research activity. It is important therefore that the Tuberculosis community is aware of the databases and tools available to them online, as well as for the database hosts to know what the needs of the research community are. One of the goals of the Tuberculosis Annotation Jamboree, held in Washington DC on March 7th-8th 2012, was therefore to provide an overview of the current status of three key Tuberculosis resources, TubercuList (tuberculist.epfl.ch), TB Database (www.tbdb.org), and Pathosystems Resource Integration Center (PATRIC, www.patricbrc.org). Here we summarize some key updates and upcoming features in TubercuList, and provide an overview of the PATRIC site and its online tools for pathogen RNA-Seq analysis.

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We present results of the paleoparasitological analysis of Cervidae coprolites that were recovered from the archaeological site Furna do Estrago, Pernambuco, Brazil. Trichuris sp. eggs were recovered from the coprolite samples dated 1,040 ± 50 years before present. This is the first record of Trichuris sp. in semiarid Cervidae, unexpectedly recorded in archaeological material.

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Hyaline fibromatosis syndrome is an autosomal recessive disease caused by mutations in ANTXR2, a gene involved in extracellular matrix homeostasis. Sixty percent of patients carry frameshift mutations at a mutational hotspot in exon 13. We show in patient cells that these mutations lead to low ANTXR2 mRNA and undetectable protein levels. Ectopic expression of the proteins encoded by the mutated genes reveals that a two base insertion leads to the synthesis of a protein that is rapidly targeted to the ER-associated degradation pathway due to the modified structure of the cytosolic tail, which instead of being hydrophilic and highly disordered as in wild type ANTXR2, is folded and exposes hydrophobic patches. In contrast, one base insertion leads to a truncated protein that properly localizes to the plasma membrane and retains partial function. We next show that targeting the nonsense mediated mRNA decay pathway in patient cells leads to a rescue of ANTXR2 protein in patients carrying one base insertion but not in those carrying two base insertions. This study highlights the importance of in-depth analysis of the molecular consequences of specific patient mutations, which even when they occur at the same site can have drastically different consequences.

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The aim of the present study was to examine the parasite fauna present in rodent coprolites collected from Cueva Huenul 1 (CH1), northern Neuquén (Patagonia, Argentina), an archaeological site that provides stratified sequences of archaeological and palaeontological remains dating from the Late Pleistocene/Early Holocene Transition to the Late Holocene period. Twenty rodent coprolites collected from different sedimentary units from the site, with ages ranging from 13.844 ± 75-1.416 ± 37 years BP, were examined for parasites. Each coprolite was processed as a whole: rehydrated, homogenised, spontaneously sedimented and examined using light microscopy. The coprolites and the eggs of any parasites present were described, measured and photographed. In all, 158 parasite eggs were found in 10 coprolites. The faeces were positive for Viscachataenia quadrata Denegri, Dopchiz, Elissondo & Beveridge and Monoecocestus sp. Beddard (Cestoda: Anoplocephalidae) and for Heteroxynema (Cavioxyura) viscaciae Sutton & Hugot (Nematoda: Oxyuridae). The coprolites examined were tentatively attributed to Lagidium viscacia Molina (Mammalia, Rodentia, Caviomorpha, Chinchillidae). The life cycles of these parasites are discussed.

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OBJECTIVE: Spirituality and religiousness have been shown to be highly prevalent among patients with schizophrenia. However, clinicians are rarely aware of the importance of religion and understand little of the value or difficulties it presents to treatment. This study aimed to assess the role of religion as a mediating variable in the process of coping with psychotic illness. METHOD: Semistructured interviews about religious coping were conducted with a sample of 115 outpatients with psychotic illness. RESULTS: For some patients, religion instilled hope, purpose, and meaning in their lives (71%), whereas for others, it induced spiritual despair (14%). Patients also reported that religion lessened (54%) or increased (10%) psychotic and general symptoms. Religion was also reported to increase social integration (28%) or social isolation (3%). It may reduce (33%) or increase (10%) the risk of suicide attempts, reduce (14%) or increase (3%) substance use, and foster adherence to (16%) or be in opposition to (15%) psychiatric treatment. CONCLUSIONS: Our results highlight the clinical significance of religion in the care of patients with schizophrenia. Religion is neither a strictly personal matter nor a strictly cultural one. Spirituality should be integrated into the psychosocial dimension of care. Our results suggest that the complexity of the relationship between religion and illness requires a highly sensitive approach to each unique story.

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A single strain of Mycobacterium abscessus subsp. bolletii, characterised by a particular rpoB sequevar and two highly related pulsed field gel electrophoresis patterns has been responsible for a nationwide outbreak of surgical infections in Brazil since 2004. In this study, we developed molecular tests based on polymerase chain reaction restriction-enzyme analysis (PRA) and sequencing for the rapid identification of this strain. Sequences of 15 DNA regions conserved in mycobacteria were retrieved from GenBank or sequenced and analysed in silico. Single nucleotide polymorphisms specific to the epidemic strain and located in enzyme recognition sites were detected in rpoB, the 3' region of the 16S rDNA and gyrB. The three tests that were developed, i.e., PRA-rpoB, PRA-16S and gyrB sequence analysis, showed 100%, 100% and 92.31% sensitivity and 93.06%, 90.28% and 100% specificity, respectively, for the discrimination of the surgical strain from other M. abscessus subsp. bolletii isolates, including 116 isolates from 95 patients, one environmental isolate and two type strains. The results of the three tests were stable, as shown by results obtained for different isolates from the same patient. In conclusion, due to the clinical and epidemiological importance of this strain, these tests could be implemented in reference laboratories for the rapid preliminary diagnosis and epidemiological surveillance of this epidemic strain.