984 resultados para mechanical pre-dewatering


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Mechanical ventilation (MV) is life-saving but potentially harmful for lungs of premature infants. So far, animal models dealt with the acute impact of MV on immature lungs, but less with its delayed effects. We used a newborn rodent model including non-surgical and therefore reversible intubation with moderate ventilation and hypothesized that there might be distinct gene expression patterns after a ventilation-free recovery period compared to acute effects directly after MV. Newborn rat pups were subjected to 8 hr of MV with 60% oxygen (O(2) ), 24 hr after injection of lipopolysaccharide (LPS), intended to create a low inflammatory background as often recognized in preterm infants. Animals were separated in controls (CTRL), LPS injection (LPS), or full intervention with LPS and MV with 60% O(2) (LPS + MV + O(2) ). Lungs were recovered either directly following (T:0 hr) or 48 hr after MV (T:48 hr). Histologically, signs of ventilator-induced lung injury (VILI) were observed in LPS + MV + O(2) lungs at T:0 hr, while changes appeared similar to those known from patients with chronic lung disease (CLD) with fewer albeit larger gas exchange units, at T:48 hr. At T:0 hr, LPS + MV + O(2) increased gene expression of pro-inflammatory MIP-2. In parallel anti-inflammatory IL-1Ra gene expression was increased in LPS and LPS + MV + O(2) groups. At T:48 hr, pro- and anti-inflammatory genes had returned to their basal expression. MMP-2 gene expression was decreased in LPS and LPS + MV + O(2) groups at T:0 hr, but no longer at T:48 hr. MMP-9 gene expression levels were unchanged directly after MV. However, at T:48 hr, gene and protein expression increased in LPS + MV + O(2) group. In conclusion, this study demonstrates the feasibility of delayed outcome measurements after a ventilation-free period in newborn rats and may help to further understand the time-course of molecular changes following MV. The differences obtained from the two time points could be interpreted as an initial transitory increase of inflammation and a delayed impact of the intervention on structure-related genes. Pediatr Pulmonol. 2012; 47:1204-1214. © 2012 Wiley Periodicals, Inc.

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Aim: The aim of the study was to investigate the influence of dietary intake of commercial hydrolyzed collagen (Gelatine Royal ®) on bone remodeling in pre-pubertal children. Methods: A randomized double-blind study was carried out in 60 children (9.42 ± 1.31 years) divided into three groups according to the amount of partially hydrolyzed collagen taken daily for 4 months: placebo (G-I, n = 18), collagen (G-II, n = 20) and collagen + calcium (G-III, n = 22) groups. Analyses of the following biochemical markers were carried out: total and bone alkaline phosphatase (tALP and bALP), osteocalcin, tartrate-resistant acid phosphatase (TRAP), type I collagen carboxy terminal telopeptide, lipids, calcium, 25-hydroxyvitamin D, insulin-like growth factor 1 (IGF-1), thyroid-stimulating hormone, free thyroxin and intact parathormone. Results: There was a significantly greater increase in serum IGF-1 in G-III than in G II (p < 0.01) or G-I (p < 0.05) during the study period, and a significantly greater increase in plasma tALP in G-III than in G-I (p < 0.05). Serum bALP behavior significantly (p < 0.05) differed between G-II (increase) and G-I (decrease). Plasma TRAP behavior significantly differed between G-II and G-I (p < 0.01) and between G-III and G-II (p < 0.05). Conclusion: Daily dietary intake of hydrolyzed collagen seems to have a potential role in enhancing bone remodeling at key stages of growth and development.

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Background: Mortality from invasive meningococcal disease (IMD) has remained stable over the last thirty years and it is unclear whether pre-hospital antibiotherapy actually produces a decrease in this mortality. Our aim was to examine whether pre-hospital oral antibiotherapy reduces mortality from IMD, adjusting for indication bias. Methods: A retrospective analysis was made of clinical reports of all patients (n = 848) diagnosed with IMD from 1995 to 2000 in Andalusia and the Canary Islands, Spain, and of the relationship between the use of pre-hospital oral antibiotherapy and mortality. Indication bias was controlled for by the propensity score technique, and a multivariate analysis was performed to determine the probability of each patient receiving antibiotics, according to the symptoms identified before admission. Data on in-hospital death, use of antibiotics and demographic variables were collected. A logistic regression analysis was then carried out, using death as the dependent variable, and prehospital antibiotic use, age, time from onset of symptoms to parenteral antibiotics and the propensity score as independent variables. Results: Data were recorded on 848 patients, 49 (5.72%) of whom died. Of the total number of patients, 226 had received oral antibiotics before admission, mainly betalactams during the previous 48 hours. After adjusting the association between the use of antibiotics and death for age, time between onset of symptoms and in-hospital antibiotic treatment, pre-hospital oral antibiotherapy remained a significant protective factor (Odds Ratio for death 0.37, 95% confidence interval 0.15–0.93). Conclusion: Pre-hospital oral antibiotherapy appears to reduce IMD mortality.

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The European Prospective Investigation into Cancer and nutrition (EPIC) is a long-term, multi-centric prospective study in Europe investigating the relationships between cancer and nutrition. This study has served as a basis for a number of Genome-Wide Association Studies (GWAS) and other types of genetic analyses. Over a period of 5 years, 52,256 EPIC DNA samples have been extracted using an automated DNA extraction platform. Here we have evaluated the pre-analytical factors affecting DNA yield, including anthropometric, epidemiological and technical factors such as center of subject recruitment, age, gender, body-mass index, disease case or control status, tobacco consumption, number of aliquots of buffy coat used for DNA extraction, extraction machine or procedure, DNA quantification method, degree of haemolysis and variations in the timing of sample processing. We show that the largest significant variations in DNA yield were observed with degree of haemolysis and with center of subject recruitment. Age, gender, body-mass index, cancer case or control status and tobacco consumption also significantly impacted DNA yield. Feedback from laboratories which have analyzed DNA with different SNP genotyping technologies demonstrate that the vast majority of samples (approximately 88%) performed adequately in different types of assays. To our knowledge this study is the largest to date to evaluate the sources of pre-analytical variations in DNA extracted from peripheral leucocytes. The results provide a strong evidence-based rationale for standardized recommendations on blood collection and processing protocols for large-scale genetic studies.

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The addition of a capped mini-exon [spliced leader (SL)] through trans-splicing is essential for the maturation of RNA polymerase (pol) II-transcribed polycistronic pre-mRNAs in all members of the Trypanosomatidae family. This process is an inter-molecular splicing reaction that follows the same basic rules of cis-splicing reactions. In this study, we demonstrated that mini-exons were added to precursor ribosomal RNA (pre-rRNA) are transcribed by RNA pol I, including the 5' external transcribed spacer (ETS) region. Additionally, we detected the SL-5'ETS molecule using three distinct methods and located the acceptor site between two known 5'ETS rRNA processing sites (A' and A1) in four different trypanosomatids. Moreover, we detected a polyadenylated 5'ETS upstream of the trans-splicing acceptor site, which also occurs in pre-mRNA trans-splicing. After treatment with an indirect trans-splicing inhibitor (sinefungin), we observed SL-5'ETS decay. However, treatment with 5-fluorouracil (a precursor of RNA synthesis that inhibits the degradation of pre-rRNA) led to the accumulation of SL-5'ETS, suggesting that the molecule may play a role in rRNA degradation. The detection of trans-splicing in these molecules may indicate broad RNA-joining properties, regardless of the polymerase used for transcription.

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Trypanosomatidae is a family of early branching eukaryotes harbouring a distinctive repertoire of gene expression strategies. Functional mature messenger RNA is generated via the trans-splicing and polyadenylation processing of constitutively transcribed polycistronic units. Recently, trans-splicing of pre-small subunit ribosomal RNA in the 5' external transcribed spacer region and of precursor tRNAsec have been described. Here, we used a previously validated semi-nested reverse transcription-polymerase chain reaction strategy to investigate internal transcribed spacer (ITS) I acceptor sites in total RNA from Leishmania (Leishmania) amazonensis. Two distinct spliced leader-containing RNAs were detected indicating that trans-splicing reactions occur at two AG acceptor sites mapped in this ITS region. These data provide further evidence of the wide spectrum of RNA molecules that act as trans-splicing acceptors in trypanosomatids.

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Purpose. This study was conducted to determine whether newer infrared or laser welding technologies created joints superior to traditional furnace or torch soldering methods of joining metals. It was designed to assess the mechanical resistance, the characteristics of the fractured surfaces, and the elemental diffusion of joints obtained by four different techniques: (1) preceramic soldering with a propane-oxygen torch, (2) postceramic soldering with a porcelain furnace, (3) preceramic and (4) postceramic soldering with an infrared heat source, and (5) laser welding. Material and methods. Mechanical resistance was determined by measuring the ultimate tensile strength of the joint and by determining their resistance to fatigue loading. Elemental diffusion to and from the joint was assessed with microprobe tracings. Scanning electron microscopy micrographs of the fractured surface were also obtained and evaluated. Results. Under monotonic tensile stress, three groups emerged: The laser welds were the strongest, the preceramic joints ranged second, and the postceramic joints were the weakest. Under fatigue stress, the order was as follows: first, the preceramic joints, and second, a group that comprised both postceramic joints and the laser welds. Inspection of the fractographs revealed several fracture modes but no consistent pattern emerged. Microprobe analyses demonstrated minor diffusion processes in the preceramic joints, whereas significant diffusion was observed in the postceramic joints. Clinical Implications. The mechanical resistance data conflicted as to the strength that could be expected of laser welded joints. On the basis of fatigue resistance of the joints, neither infrared solder joints nor laser welds were stronger than torch or furnace soldered joints.

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This review investigates ancient infectious diseases in the Americas dated to the pre-colonial period and considers what these findings can tell us about the history of the indigenous peoples of the Americas. It gives an overview, but focuses on four microbial pathogens from this period: Helicobacter pylori, Mycobacterium tuberculosis, Trypanosoma cruzi and Coccidioides immitis, which cause stomach ulceration and gastric cancer, tuberculosis, Chagas disease and valley fever, respectively. These pathogens were selected as H. pylori can give insight into ancient human migrations into the Americas, M. tuberculosis is associated with population density and urban development, T. cruzi can elucidate human living conditions and C. immitis can indicate agricultural development. A range of methods are used to diagnose infectious disease in ancient human remains, with DNA analysis by polymerase chain reaction one of the most reliable, provided strict precautions are taken against cross contamination. The review concludes with a brief summary of the changes that took place after European exploration and colonisation.

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Durante los procedimientos endovasculares en el ictus isquémico la información per-procedimiento del daño cerebral ayudaría a tomar decisiones sobre intentar la recanalización arterial. Métodos Se estudiaron parámetros gasométricos de sangre extraída durante los procedimientos endovasculares de recanalización. Se obtuvieron muestras proximal y distal a la oclusión. Un estudio gasométrico se realizo inmediatamente. Resultados El estudio mostró diferencias significativas entre las muestras pre-oclusión y postoclusión en la presión parcial de oxígeno (PaO2Pre78,9±16.3mmHgVs73.4±14.9 mmHg,p&0,001). Una curva ROC determinó que una Post-PaO2&70 mmHg predice mejoría clínica. Los pacientes con post-PaO2&70mmHg tuvieron mejor autonomía (medianaMRS:3Vs.6, p=0,024). En el análisis multivariante el único predictor independiente de mejoría clínica fue la Post-PaO2&70(OR:5,21IC95%:1.38-67.24,p=0,013). Conclusión Es posible la obtención de muestras de sangre del tejido lesionado distal a la oclusión. La información puede ser utilizada para predecir evolución clínica y en las decisiones durante el procedimiento.