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In this task, you're given a paragraph from the research paper and your task is to generate a suitable title for the research paper based on the given paper. Under 100 words is a good title length.
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Background: Porcine circovirus type 2 (PCV2) has been associated with several disease complexes, including reproductive failure. The aim of this study was to identify the subtypes of PCV2 that are associated with reproductive failure in pigs from the State of São Paulo, Brazil and to investigate co-infections with other infectious organisms. Findings: Samples of 168 aborted foetuses or mummified foetuses from five farrow-to-finish swine farms known to be infected with PCV2 and located in the State of São Paulo were tested for PCV2 by polymerase chain reaction (PCR). Positive samples were additionally tested for porcine parvovirus (PPV), Leptospira spp. and Brucella spp. by PCR. PCV2 was detected in 18 of the samples (10.7%). PPV, Brucella spp. and Leptospira spp were found in 2, 10 and 0 cases, respectively. Eleven PCV2 strains were sequenced and determined to be either genotype 2a (n = 1) or 2b (n = 10). The findings indicate that the frequency of PCV2 infections in aborted porcine foetuses from the State of São Paulo is rather low (10.7%) and that co-infection with other pathogens is common and may be involved in PCV2 associated reproductive failure. No repeatable, characteristic amino acid motifs for regions of the PCV2 capsid protein seemed to be associated with abortion in sows.
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Detection of porcine circovirus genotypes 2a and 2b in aborted foetuses from infected swine herds in the State of São Paulo, Brazil


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with the pathological structure of BPD, as seen in the lungs of preterm infants who died and in animal models (3, 7). As the authors note, this study was limited in that the subjects with BPD were stable outpatients younger than 3 years who did not require oxygen therapy at the time of the study. Whether their findings hold true in infants with persistent severe BPD, including those with chronic ventilator-dependent hypoxemic respiratory failure, is not clear. In addition, BPD classification was based on clinical decision making, rather than a physiologic assessment such as the oxygen reduction test (11). In an earlier article, members of this group studied DL CO and its components, DM and Vc, in full-term infants without lung disease and showed that DL CO and Vc (but not DM) correlated with the level of proangiogenic circulating hematopoietic stem/progenitor cells (pCHSPCs) (12). However, this study did not include preterm infants with or without BPD. Both pCHSPCs, also referred to as circulating progenitor cells, as well as late-outgrowth endothelial colony-forming cells, are decreased in the cord blood of preterm infants who later develop moderate or severe BPD (13, 14) . Together, these findings suggest that early disruptions in the number and function of angiogenic progenitor cells, possibly by maternal complications of pregnancy known to be associated with BPD risk, may lead to impaired development of the pulmonary vasculature and sustained impaired gas exchange in preterm infants with BPD. This study shows how a physiologic assessment, such as infant pulmonary function testing, may be used in the clinical setting to provide an estimation of impaired gas exchange in preterm infants with varying degrees of lung injury. Combining functional assays such as this with measurement of pCHSPCs and other angiogenic biomarkers in the cord blood, as well as novel imaging techniques such as quantitative pulmonary magnetic resonance imaging (15), will lead to improved disease phenotyping of preterm infants at risk for BPD. Given the spectrum of disease severity among infants with severe BPD (as determined by the currently accepted diagnostic criteria), novel methods such as these will help identify preterm neonates more accurately, permit targeted therapies for the most severely affected infants, and provide quantitative evidence of the efficacy of these interventions in young children after preterm birth (16). n
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Jobe AH, Bancalari E. Bronchopulmonary dysplasia


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Dysfunction of CFTR in cystic fibrosis (CF) airway epithelium perturbs the normal regulation of ion transport, leading to a reduced volume of airway surface liquid (ASL), mucus dehydration, decreased mucus transport, and mucus plugging of the airways. CFTR is normally expressed in ciliated epithelial cells of the surface and submucosal gland ductal epithelium and submucosal gland acinar cells. Critical questions for the development of gene transfer strategies for CF airway disease are what airway regions require CFTR function and how many epithelial cells require CFTR expression to restore normal ASL volume regulation and mucus transport to CF airway epithelium? An in vitro model of human CF ciliated surface airway epithelium (CF HAE) was used to test whether a human parainfluenza virus (PIV) vector engineered to express CFTR (PIVCFTR) could deliver sufficient CFTR to CF HAE to restore mucus transport, thus correcting the CF phenotype. PIVCFTR delivered CFTR to .60% of airway surface epithelial cells and expressed CFTR protein in CF HAE approximately 100-fold over endogenous levels in non-CF HAE. This efficiency of CFTR delivery fully corrected the basic bioelectric defects of Cl 2 and Na + epithelial ion transport and restored ASL volume regulation and mucus transport to levels approaching those of non-CF HAE. To determine the numbers of CF HAE surface epithelial cells required to express CFTR for restoration of mucus transport to normal levels, different amounts of PIVCFTR were used to express CFTR in 3%-65% of the surface epithelial cells of CF HAE and correlated to increasing ASL volumes and mucus transport rates. These data demonstrate for the first time, to our knowledge, that restoration of normal mucus transport rates in CF HAE was achieved after CFTR delivery to 25% of surface epithelial cells. In vivo experimentation in appropriate models will be required to determine what level of mucus transport will afford clinical benefit to CF patients, but we predict that a future goal for corrective gene transfer to the CF human airways in vivo would attempt to target at least 25% of surface epithelial cells to achieve mucus transport rates comparable to those in non-CF airways.
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CFTR Delivery to 25% of Surface Epithelial Cells Restores Normal Rates of Mucus Transport to Human Cystic Fibrosis Airway Epithelium