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1.

Introduction  

Positive end-expiratory pressure (PEEP)-induced lung derecruitment can be assessed by a pressure–volume (P–V) curve method or by lung computed tomography (CT). However, only the first method can be used at the bedside. The aim of the study was to compare both methods for assessing alveolar derecruitment after the removal of PEEP in patients with acute lung injury or acute respiratory distress syndrome.  相似文献   
2.
Background: Pulmonary concentrations of aminoglycosides administered intravenously are usually low in the infected lung parenchyma. Nebulization represents an alternative to increase pulmonary concentrations, although the obstruction of bronchioles by purulent plugs may impair lung deposition by decreasing lung aeration.

Methods: An experimental bronchopneumonia was induced in anesthetized piglets by inoculating lower lobes with a suspension of 106 cfu/ml Escherichia coli. After 24 h of mechanical ventilation, 7 animals received two intravenous injections of 15 mg/kg amikacin, and 11 animals received two nebulizations of 40 mg/kg amikacin at 24-h intervals. One hour following the second administration, animals were killed, and multiple lung specimens were sampled for assessing amikacin pulmonary concentrations and quantifying lung aeration on histologic sections.

Results: Thirty-eight percent of the nebulized amikacin (15 mg/kg) reached the tracheobronchial tree. Amikacin pulmonary concentrations were always higher after nebulization than after intravenous administration, decreased with the extension of parenchymal infection, and were significantly influenced by lung aeration: 197 +/- 165 versus 6 +/- 5 [mu]g/g in lung segments with focal bronchopneumonia (P = 0.03), 40 +/- 62 versus 5 +/- 3 [mu]g/g in lung segments with confluent bronchopneumonia (P = 0.001), 18 +/- 7 versus 7 +/- 4 [mu]g/g in lung segments with lung aeration of 30% or less, and 65 +/- 9 versus 2 +/- 3 [mu]g/g in lung segments with lung aeration of 50% or more.  相似文献   

3.
Because organ transplantation is the preferred treatment for organ failure, the demand for human organs for transplantation is large and growing. From this demand, several fields based on new technologies for the replacement or repair of damaged tissues and organs have emerged. These fields include stem cell biology, cloning, tissue engineering and xenotransplantation. Here we evaluate the potential contribution of these to the devising of alternative approaches to organ replacement. We present our vision for the development of two structurally complex organs – the lung and the kidney – based on a 'fusion' of new and established technologies.  相似文献   
4.
We investigated the effects of oral L-glutamine (Gln) supplementation, associated or not with physical exercises, in control of glycemia, oxidative stress, and strength/power of knee muscles in elderly women. Physically active (n = 21) and sedentary (n = 23) elderly women aged 60 to 80 years were enrolled in the study. Plasma levels of D-fructosamine, insulin, reduced (GSH) and oxidized (GSSG) glutathione, iron, uric acid, and thiobarbituric acid-reactive substances (TBARs) (lipoperoxidation product), as well as knee extensor/flexor muscle torque peak and average power (isokinetic test), were assessed pre- and post-supplementation with Gln or placebo (30 days). Higher plasma D-fructosamine, insulin, and iron levels, and lower strength/power of knee muscles were found pre-supplementation in the NPE group than in the PE group. Post-supplementation, Gln subgroups showed higher levels of GSH, GSSG, and torque peak, besides lower D-fructosamine than pre-supplementation values. Higher muscle average power and plasma uric acid levels were reported in the PE + Gln group, whereas lower insulin levels were found in the NPE + Gln than pre-supplementation values. TBARs levels were diminished post-supplementation in all groups. Gln supplementation, mainly when associated with physical exercises, improves strength and power of knee muscles and glycemia control, besides boosting plasma antioxidant capacity of elderly women.  相似文献   
5.
Although there is a large body of research connecting emotion to eating behaviors, little is known about the role of caregivers’ responses to children’s emotions in the context of child feeding. The purpose of this study was to analyze the relation between caregivers’ emotional responsiveness and feeding responsiveness. The mothers of 137 children between 2 and 6 years of age reported on their responses to children’s negative emotions using the Coping with Children’s Negative Emotions Scale and on their feeding practices using the Comprehensive Feeding Practices Questionnaire. The results showed that mothers’ supportive emotion responses (e.g., problem-focused, emotion-focused, and expressive encouragement reactions) tend to be positively associated with responsive feeding practices (e.g., encouraging, modelling, and teaching healthy food-related behaviors). Instead, mothers’ unsupportive responses (e.g., distress, punitive and minimization reactions) tend to be positively associated with nonresponsive feeding practices (e.g., food as reward or to regulate emotions, and pressure to eat) and negatively associated with responsive feeding practices. Our results suggest that emotional and feeding responsiveness may be intertwined and that differences in parent’s emotional responsiveness may translate into differences in their feeding styles, setting the stage for parents’ use of positive vs. negative feeding practices.  相似文献   
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Background:The eye is an important sensory organ occupationally exposed to ionizing radiation (IR) in healthcare workers (HCWs) engaged in medical imaging (MI). New evidence highlights the possible induction of cataract at IR exposure levels to be much lower than expected in the past.Objective:Conduct an updated review on the current evidence on cataract risk in healthcare workers exposed to IR.Methods:Published scientific studies on cataract risk in IR exposed healthcare workers were collected through a systematic search of two biomedical databases (MEDLINE and Scopus). Data from included studies was extracted and summarized. Study quality was also assessed.Results:All 21 eligible studies reported an increased prevalence of cataract, especially posterior subcapsular cataract, in IR exposed HCWs with a higher prevalence in interventional cardiology staff.Discussion:Our review synthesizes the latest evidence to support the hypothesis of a significantly increased risk of occupational cataract in healthcare workers operating MI and exposed to IR, especially in interventional cardiologists. Data also support a dose-response relationship between IR exposure and the prevalence of opacities, especially posterior subcapsular opacities.Conclusions:Findings highlight the need for effective control measures including appropriate training, adherence to protective procedures, and a constant use of shields and eye personal protective equipment in healthcare workers with optical exposure to IR. Periodic health surveillance programs, possibly including lens evaluation, are also important to monitor cataract risk in these MI operators.Key words: Healthcare workers, ionizing radiation, cataract, radiation, radiology, radiologist work-related injury, occupational injury, occupational exposure, interventional radiology, radiation protection, radiation-induced cataract, interventional fluoroscopy, dosimetry, radiation workers, dosimeter, radiation effects  相似文献   
10.
The inflammatory processes in the joints of a child with juvenile idiopathic arthritis (JIA) can persist into adulthood. Inflammation has been linked to distortions of the lipid profile and accelerated atherogenesis. In the present study, we examined the lipid profiles of adults with JIA compared with those of healthy people. A lipid profile of a sample of 54 adults with JIA (57.3% with polyarticular JIA, 37.0% with oligoarticular JIA, 1.9% with enthesitis-related JIA and 3.7% with systemic onset JIA) and 54 healthy subjects were compared. In the adults with JIA, data on gender, age, age at disease onset, the presence of rheumatoid factor (RF) and antinuclear antibodies (ANA), a Health Assessment Questionnaire (HAQ) and the disease duration were collected. We found that hypercholesterolaemia, increased low-density lipoprotein (LDL) and decreased high-density lipoprotein (HDL) were more common in patients with JIA than the controls (P = 0.016, P < 0.0001 and P = 0.0008, respectively). Changes in the levels of total cholesterol (TC) and LDL were more common in the individuals who had a later onset of disease (P = 0.0017 for TC and P = 0.023 for LDL). In the entire JIA group, no other variable, such as RF, ANA, disease duration or responses to the HAQ, could be linked to dyslipidaemia (P = non-significant). We concluded that the adult patients with JIA have a lipid profile with increased TC and LDL levels and decreased levels of HDL compared to the controls. No clinical feature could be correlated with this change except for the age at disease onset.  相似文献   
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