Formation of γ-H2AX in response to DNA double stranded breaks (DSBs) provides the basis for a sensitive assay of DNA damage in human biopsies. The review focuses on the application of γ-H2AX-based ...methods to translational studies to monitor the clinical response to DNA targeted therapies such as some forms of chemotherapy, external beam radiotherapy, radionuclide therapy or combinations thereof. The escalating attention on radiation biodosimetry has also highlighted the potential of the assay including renewed efforts to assess the radiosensitivity of prospective radiotherapy patients. Finally the γ-H2AX response has been suggested as a basis for an in vivo imaging modality.
A finite element model is introduced in this paper to describe the coupling between the welding arc and the weld pool dynamic in pulsed gas tungsten arc welding. The cathode, arc-plasma and melting ...anode regions are taken into account. The unified time-dependent model describes the heat transfer, fluid flow and electromagnetic fields in the three regions. The originality of the numerical model is its ability to treat the arc and weld pool time evolution under pulsed current welding in a unified formalism, taking into account eddy current in the weld pool. The case of thin plates with fully penetrated weld pools is also handled.
To validate the predictions of the model, an Infra-Red camera is used to film the dynamic of the weld pool surface. Then an image processing algorithm permits to get the time evolution of the weld pool width directly from the film. The numerical model is applied to the 304 stainless steel welding, and the computed results show that the predictions are in fair agreement with the experimental results.
We designed a multicenter randomized trial to compare 3 approaches to the initial respiratory management of preterm neonates: prophylactic surfactant followed by a period of mechanical ventilation ...(prophylactic surfactant PS); prophylactic surfactant with rapid extubation to bubble nasal continuous positive airway pressure (intubate-surfactant-extubate ISX) or initial management with bubble continuous positive airway pressure and selective surfactant treatment (nCPAP).
Neonates born at 26 0/7 to 29 6/7 weeks' gestation were enrolled at participating Vermont Oxford Network centers and randomly assigned to PS, ISX, or nCPAP groups before delivery. Primary outcome was the incidence of death or bronchopulmonary dysplasia (BPD) at 36 weeks' postmenstrual age.
648 infants enrolled at 27 centers. The study was halted before the desired sample size was reached because of declining enrollment. When compared with the PS group, the relative risk of BPD or death was 0.78 (95% confidence interval: 0.59-1.03) for the ISX group and 0.83 (95% confidence interval: 0.64-1.09) for the nCPAP group. There were no statistically significant differences in mortality or other complications of prematurity. In the nCPAP group, 48% were managed without intubation and ventilation, and 54% without surfactant treatment.
Preterm neonates were initially managed with either nCPAP or PS with rapid extubation to nCPAP had similar clinical outcomes to those treated with PS followed by a period of mechanical ventilation. An approach that uses early nCPAP leads to a reduction in the number of infants who are intubated and given surfactant.
Traditionally, surfactant has been administered to preterm infants with respiratory distress syndrome via an endotracheal tube and in conjunction with mechanical ventilation. However, negative ...consequences of mechanical ventilation such as pneumothorax and bronchopulmonary dysplasia are well known. In order to provide the benefits of surfactant administration without the negative effects of mechanical ventilation, several methods of less invasive surfactant administration have been developed. These methods include InSurE (intubate, surfactant, extubate), pharyngeal administration, laryngeal mask administration, aerosolized surfactant administration, and thin catheter administration (TCA). Of these, TCA has been studied most extensively and holds the most promise as a less invasive and effective mode of surfactant administration to preterm infants. Further studies will aid in determining which patients would benefit most from less invasive surfactant administration.
Mitochondrially generated reactive oxygen species are involved in a myriad of signaling and damaging pathways in different tissues. In addition, mitochondria are an important target of reactive ...oxygen and nitrogen species. Here, we discuss basic mechanisms of mitochondrial oxidant generation and removal and the main factors affecting mitochondrial redox balance. We also discuss the interaction between mitochondrial reactive oxygen and nitrogen species, and the involvement of these oxidants in mitochondrial diseases, cancer, neurological, and cardiovascular disorders.
This manuscript represents an appraisal of the evidence in support of
l
-ornithine-
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-aspartate (LOLA) for the management and treatment of hepatic encephalopathy (HE) in cirrhosis. Meta-analyses of ...randomized controlled trials (RCTs) conducted over the last two decades generally reveal evidence of benefit of LOLA in a range of clinical presentations. This included improvement of mental state grade in overt HE (OHE) assessed by West Haven criteria as well as in minimal HE (MHE) assessed by psychometric testing where the oral formulation of LOLA was determined to be particularly effective. However, concerns over study quality were noted in one meta-analysis. Nevertheless, the concomitant lowering of fasting blood ammonia was reported in all RCTs using this endpoint. Network meta-analyses showed that LOLA appears to be comparable (or superior) in efficacy to non-absorbable disaccharides or probiotics. Emerging evidence from single RCTs show efficacy of LOLA for the treatment of post-transjugular intrahepatic portosystemic shunt (TIPSS) HE as well as for secondary HE prophylaxis. These findings provide support for the use of LOLA in the treatment of HE and future trials should focus on the use of LOLA for prophylaxis.
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