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1.
Samar Farha Daniel Laskowski Deepa George Margaret M Park WH Wilson Tang Raed A Dweik Serpil C Erzurum 《Respiratory research》2013,14(1):6
Background
Reduced gas transfer in patients with pulmonary arterial hypertension (PAH) is traditionally attributed to remodeling and progressive loss of pulmonary arterial vasculature that results in decreased capillary blood volume available for gas exchange.Methods
We tested this hypothesis by determination of lung diffusing capacity (DL) and its components, the alveolar capillary membrane diffusing capacity (Dm) and lung capillary blood volume (Vc) in 28 individuals with PAH in comparison to 41 healthy individuals, and in 19 PAH patients over time. Using single breath simultaneous measure of diffusion of carbon monoxide (DLCO) and nitric oxide (DLNO), DL and Dm were respectively determined, and Vc calculated. Dm and Vc were evaluated over time in relation to standard clinical indicators of disease severity, including brain natriuretic peptide (BNP), 6-minute walk distance (6MWD) and right ventricular systolic pressure (RVSP) by echocardiography.Results
Both DLCO and DLNO were reduced in PAH as compared to controls and the lower DL in PAH was due to loss of both Dm and Vc (all p < 0.01). While DLCO of PAH patients did not change over time, DLNO decreased by 24 ml/min/mmHg/year (p = 0.01). Consequently, Dm decreased and Vc tended to increase over time, which led to deterioration of the Dm/Vc ratio, a measure of alveolar-capillary membrane functional efficiency without changes in clinical markers.Conclusions
The findings indicate that lower than normal gas transfer in PAH is due to loss of both Dm and Vc, but that deterioration of Dm/Vc over time is related to worsening membrane diffusion. 相似文献2.
Wei-jie Guan Yong-hua Gao Gang Xu Zhi-ya Lin Yan Tang Hui-min Li Zhi-min Lin Jin-ping Zheng Rong-chang Chen Nan-shan Zhong 《PloS one》2014,9(11)
Background
Characteristics of lung function impairment in bronchiectasis is not fully understood.Objectives
To determine the factors associated with lung function impairment and to compare changes in spirometry during bronchiectasis exacerbation and convalescence (1 week following 14-day antibiotic therapy).Methods
We recruited 142 patients with steady-state bronchiectasis, of whom 44 with acute exacerbations in the follow-up were included in subgroup analyses. Baseline measurements consisted of chest high-resolution computed tomography (HRCT), sputum volume, purulence and bacteriology, spirometry and diffusing capacity. Spirometry, but not diffusing capacity, was examined during acute exacerbations and convalescence.Results
In the final multivariate models, having bronchiectasis symptoms for 10 years or greater (OR = 4.75, 95%CI: 1.46–15.43, P = 0.01), sputum culture positive for Pseudomonas aeruginosa (OR = 4.93, 95%CI: 1.52–15.94, P<0.01) and HRCT total score being 12 or greater (OR = 7.77, 95%CI: 3.21–18.79, P<0.01) were the major variables associated with FEV1 being 50%pred or less; and the only variable associated with reduced DLCO was 4 or more bronchiectatic lobes (OR = 5.91, 95%CI: 2.20–17.23, P<0.01). Overall differences in FVC and FEV1 during exacerbations and convalescence were significant (P<0.05), whereas changes in other spirometric parameters were less notable. This applied even when stratified by the magnitude of FEV1 and DLCO reduction at baseline.Conclusion
Significant lung function impairment should raise alert of chest HRCT abnormality and sputum culture positive for Pseudomonas aeruginosa, in patients with predominantly mild to moderate steady-state bronchiectasis. Acute exacerbations elicited reductions in FVC and FEV1. Changes of other spirometric parameters were less significant during exacerbations.Trial Registration
ClinicalTrials.gov NCT01761214相似文献3.
Background
Increasing atmospheric CO2 and nitrogen (N) deposition across the globe may affect ecosystem CO2 exchanges and ecosystem carbon cycles. Additionally, it remains unknown how increased N deposition and N addition will alter the effects of elevated CO2 on wetland ecosystem carbon fluxes.Methodology/Principal Findings
Beginning in 2010, a paired, nested manipulative experimental design was used in a temperate wetland of northeastern China. The primary factor was elevated CO2, accomplished using Open Top Chambers, and N supplied as NH4NO3 was the secondary factor. Gross primary productivity (GPP) was higher than ecosystem respiration (ER), leading to net carbon uptake (measured by net ecosystem CO2 exchange, or NEE) in all four treatments over the growing season. However, their magnitude had interannual variations, which coincided with air temperature in the early growing season, with the soil temperature and with the vegetation cover. Elevated CO2 significantly enhanced GPP and ER but overall reduced NEE because the stimulation caused by the elevated CO2 had a greater impact on ER than on GPP. The addition of N stimulated ecosystem C fluxes in both years and ameliorated the negative impact of elevated CO2 on NEE.Conclusion/Significance
In this ecosystem, future elevated CO2 may favor carbon sequestration when coupled with increasing nitrogen deposition. 相似文献4.
Kuang-Hsi Chang Mei-Yin Chang Chih-Hsin Muo Trong-Neng Wu Chiu-Ying Chen Chia-Hung Kao 《PloS one》2014,9(8)
Background
The air pollution caused by vehicular emissions is associated with cognitive decline. However, the associations between the levels of nitrogen dioxide (NO2) and carbon monoxide (CO) exposure and dementia remain poorly defined and have been addressed in only a few previous studies.Materials and Methods
In this study, we obtained data on 29547 people from the National Health Insurance Research Database (NHIRD) of Taiwan, including data on 1720 patients diagnosed with dementia between 2000 and 2010, and we evaluated the risk of dementia among four levels of air pollutant. Detailed data on daily air pollution were available from January 1, 1998 to December 31, 2010. Yearly average concentrations of pollutants were calculated from the baseline to the date of dementia occurrence, withdrawal of patients, or the end of the study, and these data were categorized into quartiles, with Q1 being the lowest level and Q4 being the highest.Results
In the case of NO2, the adjusted hazard ratios (HRs) of dementia for all participants in Q2, Q3, and Q4 compared to Q1 were 1.10 (95% confidence interval (CI), 0.96–1.26), 1.01 (95% CI, 0.87–1.17), and 1.54 (95% CI, 1.34–1.77), and in the case of CO, the adjusted HRs were 1.07 (95% CI, 0.92–1.25), 1.37 (95% CI, 1.19–1.58), and 1.61 (95% CI, 1.39–1.85).Conclusion
The results of this large retrospective, population-based study indicate that exposure to NO2 and CO is associated with an increased risk of dementia in the Taiwanese population. 相似文献5.
Tsung-Ming Tsao Ming-Jer Tsai Ya-Nan Wang Heng-Lun Lin Chang-Fu Wu Jing-Shiang Hwang Sandy-H.J. Hsu Hsing Chao Kai-Jen Chuang Charles- CK. Chou Ta-Chen Su 《PloS one》2014,9(7)
Background
Assessment of health effects of a forest environment is an important emerging area of public health and environmental sciences.Purpose
To demonstrate the long-term health effects of living in a forest environment on subclinical cardiovascular diseases (CVDs) and health-related quality of life (HRQOL) compared with that in an urban environment.Materials and Methods
This study included the detailed health examination and questionnaire assessment of 107 forest staff members (FSM) and 114 urban staff members (USM) to investigate the long-term health effects of a forest environment. Air quality monitoring between the forest and urban environments was compared. In addition, work-related factors and HRQOL were evaluated.Results
Levels of total cholesterol, low-density lipoprotein cholesterol, and fasting glucose in the USM group were significantly higher than those in the FSM group. Furthermore, a significantly higher intima-media thickness of the internal carotid artery was found in the USM group compared with that in the FSM group. Concentrations of air pollutants, such as NO, NO2, NOx, SO2, CO, PM2.5, and PM10 in the forest environment were significantly lower compared with those in the outdoor urban environment. Working hours were longer in the FSM group; however, the work stress evaluation as assessed by the job content questionnaire revealed no significant differences between FSM and USM. HRQOL evaluated by the World Health Organization Quality of Life-BREF questionnaire showed FSM had better HRQOL scores in the physical health domain.Conclusions
This study provides evidence of the potential beneficial effects of forest environments on CVDs and HRQOL. 相似文献6.
Mandeep S. Jassal Gueno G. Nedeltchev Jong-Hee Lee Seong Won Choi Viorel Atudorei Zachary D. Sharp Vojo Deretic Graham S. Timmins William R. Bishai 《PloS one》2010,5(8)
Background
Pathogen-specific metabolic pathways may be detected by breath tests based on introduction of stable isotopically-labeled substrates and detection of labeled products in exhaled breath using portable infrared spectrometers.Methodology/Principal Findings
We tested whether mycobacterial urease activity could be utilized in such a breath test format as the basis of a novel biomarker and diagnostic for pulmonary TB. Sensitized New-Zealand White Rabbits underwent bronchoscopic infection with either Mycobacterium bovis or Mycobacterium tuberculosis. Rabbits were treated with 25 mg/kg of isoniazid (INH) approximately 2 months after infection when significant cavitary lung pathology was present. [13C] urea was instilled directly into the lungs of intubated rabbits at selected time points, exhaled air samples analyzed, and the kinetics of δ13CO2 formation were determined. Samples obtained prior to inoculation served as control samples for background 13CO2 conversion in the rabbit model. 13CO2, from metabolic conversion of [13C]-urea by mycobacterial urease activity, was readily detectable in the exhaled breath of infected rabbits within 15 minutes of administration. Analyses showed a rapid increase in the rate of 13CO2 formation both early in disease and prior to treatment with INH. Following INH treatment, all evaluable rabbits showed a decrease in the rate of 13CO2 formation.Conclusions/Significance
Urea breath testing may provide a useful diagnostic and biomarker assay for tuberculosis and for treatment response. Future work will test specificity for M. tuberculosis using lung-targeted dry powder inhalation formulations, combined with co-administering oral urease inhibitors together with a saturating oral dose of unlabeled urea, which would prevent the δ13CO2 signal from urease-positive gastrointestinal organisms. 相似文献7.
Amanda Ribeiro de Oliveira Ana Caroline Colombo Sangu Muthuraju Rafael Carvalho Almada Marcus Lira Brand?o 《PloS one》2014,9(8)
Background
A reduction of dopamine release or D2 receptor blockade in the terminal fields of the mesolimbic system clearly reduces conditioned fear. Injections of haloperidol, a preferential D2 receptor antagonist, into the inferior colliculus (IC) enhance the processing of unconditioned aversive information. However, a clear characterization of the interplay of D2 receptors in the mediation of unconditioned and conditioned fear is still lacking.Methods
The present study investigated the effects of intra-IC injections of the D2 receptor-selective antagonist sulpiride on behavior in the elevated plus maze (EPM), auditory-evoked potentials (AEPs) to loud sounds recorded from the IC, fear-potentiated startle (FPS), and conditioned freezing.Results
Intra-IC injections of sulpiride caused clear proaversive effects in the EPM and enhanced AEPs induced by loud auditory stimuli. Intra-IC sulpiride administration did not affect FPS or conditioned freezing.Conclusions
Dopamine D2-like receptors of the inferior colliculus play a role in the modulation of unconditioned aversive information but not in the fear-potentiated startle response. 相似文献8.
Rationale
Both atopy and smoking are known to be associated with increased bronchial responsiveness. Fraction of nitric oxide (NO) in the exhaled air (FENO), a marker of airways inflammation, is decreased by smoking and increased by atopy. NO has also a physiological bronchodilating and bronchoprotective role.Objectives
To investigate how the relation between FENO and bronchial responsiveness is modulated by atopy and smoking habits.Methods
Exhaled NO measurements and methacholine challenge were performed in 468 subjects from the random sample of three European Community Respiratory Health Survey II centers: Turin (Italy), Gothenburg and Uppsala (both Sweden). Atopy status was defined by using specific IgE measurements while smoking status was questionnaire-assessed.Main Results
Increased bronchial responsiveness was associated with increased FENO levels in non-smokers (p = 0.02) and decreased FENO levels in current smokers (p = 0.03). The negative association between bronchial responsiveness and FENO was seen only in the group smoking less <10 cigarettes/day (p = 0.008). Increased bronchial responsiveness was associated with increased FENO in atopic subjects (p = 0.04) while no significant association was found in non-atopic participants. The reported interaction between FENO and smoking and atopy, respectively were maintained after adjusting for possible confounders (p-values<0.05).Conclusions
The present study highlights the interactions of the relationship between FENO and bronchial responsiveness with smoking and atopy, suggesting different mechanisms behind atopy- and smoking-related increases of bronchial responsiveness. 相似文献9.
Hui-Hsien Pan Chun-Tzu Chen Hai-Lun Sun Min-Sho Ku Pei-Fen Liao Ko-Hsiu Lu Ji-Nan Sheu Jing-Yang Huang Jar-Yuan Pai Ko-Huang Lue 《PloS one》2014,9(5)
Background
A nationwide asthma survey on the effects of air pollution is lacking in Taiwan. The purpose of this study was to evaluate the time trend and the relationship between air pollution and health care services for asthma in Taiwan.Methods
Health care services for asthma and ambient air pollution data were obtained from the National Health Insurance Research database and Environmental Protection Administration from 2000 through 2009, respectively. Health care services, including those related to the outpatient and inpatient visits were compared according to the concentration of air pollutants.Results
The number of asthma-patient visits to health-care facilities continue to increase in Taiwan. Relative to the respective lowest quartile of air pollutants, the adjusted relative risks (RRs) of the outpatient visits in the highest quartile were 1.10 (P-trend = 0.013) for carbon monoxide (CO), 1.10 (P-trend = 0.015) for nitrogen dioxide (NO2), and 1.20 (P-trend <0.0001) for particulate matter with an aerodynamic diameter ≦10µm (PM10) in the child group (aged 0–18). For adults aged 19–44, the RRs of outpatient visits were 1.13 (P-trend = 0.078) for CO, 1.17 (P-trend = 0.002) for NO2, and 1.13 (P-trend <0.0001) for PM10. For adults aged 45–64, the RRs of outpatient visits were 1.15 (P-trend = 0.003) for CO, 1.19 (P-trend = 0.0002) for NO2, and 1.10 (P-trend = 0.001) for PM10. For the elderly (aged≥ 65), the RRs of outpatient visits in were 1.12 (P-trend = 0.003) for NO2 and 1.10 (P-trend = 0.006) for PM10. For inpatient visits, the RRs across quartiles of CO level were 1.00, 1.70, 1.92, and 1.86 (P-trend = 0.0001) in the child group. There were no significant linear associations between inpatient visits and air pollutants in other groups.Conclusions
There were positive associations between CO levels and childhood inpatient visits as well as NO2, CO and PM10 and outpatient visits. 相似文献10.
Han Sam Cho Dae Jung Baek Seung Soo Baek 《Journal of Exercise Nutrition & Biochemistry》2014,18(4):379-384
[Purpose]
Attention-deficit/hyperactivity disorder (ADHD) is a heritable, chronic, neurobehavioral disorder that is characterized by hyperactivity, inattention, and impulsivity. It is commonly believed that the symptoms of ADHD are closely associated with hypo-function of the dopamine system. Dopamine D2 receptor activation decreases the excitability of dopamine neurons, as well as the release of dopamine. Physical exercise is known to improve structural and functional impairments in neuropsychiatric disorders. We investigated the therapeutic effect of exercise on ADHD.[Methods]
Open field task and elevated-plus maze task were used in the evaluation of hyperactivity and impulsivity, respectively. Dopamine D2 receptor expression in the substantia nigra and striatum were evaluated by western blotting.[Results]
The present results indicated that ADHD rats showed hyperactivity and impulsivity. Dopamine D2 receptor expression in the substantia nigra and striatum were increased in ADHD rats. Exercise alleviated hyperactivity and impulsivity in ADHD rats. Furthermore, dopamine D2 receptor expression in ADHD rats was also decreased by exercise.[Conclusion]
We thus showed that exercise effectively alleviates ADHD-induced symptoms through enhancing dopamine D2 expression in the brain. 相似文献11.
Pierachille Santus Antonio Russo Enzo Madonini Luigi Allegra Francesco Blasi Stefano Centanni Antonio Miadonna Gianfranco Schiraldi Sandro Amaducci 《Respiratory research》2012,13(1):95
Background
Environmental pollution is a known risk factor for multiple diseases and furthermore increases rate of hospitalisations. We investigated the correlation between emergency room admissions (ERAs) of the general population for respiratory diseases and the environmental pollutant levels in Milan, a metropolis in northern Italy.Methods
We collected data from 45770 ERAs for respiratory diseases. A time-stratified case-crossover design was used to investigate the association between air pollution levels and ERAs for acute respiratory conditions. The effects of air pollutants were investigated at lag 0 to lag 5, lag 0–2 and lag 3–5 in both single and multi-pollutant models, adjusted for daily weather variables.Results
An increase in ozone (O3) levels at lag 3–5 was associated with a 78% increase in the number of ERAs for asthma, especially during the warm season. Exposure to carbon monoxide (CO) proved to be a risk factor for pneumonia at lag 0–2 and in the warm season increased the risk of ERA by 66%. A significant association was found between ERAs for COPD exacerbation and levels of sulphur dioxide (SO2), CO, nitrate dioxide (NO2), and particulate matter (PM10 and PM2.5). The multipollutant model that includes all pollutants showed a significant association between CO (26%) and ERA for upper respiratory tract diseases at lag 0–2. For chronic obstructive pulmonary disease (COPD) exacerbations, only CO (OR 1.19) showed a significant association.Conclusions
Exposure to environmental pollution, even at typical low levels, can increase the risk of ERA for acute respiratory diseases and exacerbation of obstructive lung diseases in the general population. 相似文献12.
Marc Feissel Ludwig Serge Aho Stefan Georgiev Romain Tapponnier Julio Badie Rémi Bruyère Jean-Pierre Quenot 《PloS one》2015,10(6)
Background
We determined reliability of cardiac output (CO) measured by pulse wave transit time cardiac output system (esCCO system; COesCCO) vs transthoracic echocardiography (COTTE) in mechanically ventilated patients in the early phase of septic shock. A secondary objective was to assess ability of esCCO to detect change in CO after fluid infusion.Methods
Mechanically ventilated patients admitted to the ICU, aged >18 years, in sinus rhythm, in the early phase of septic shock were prospectively included. We performed fluid infusion of 500ml of crystalloid solution over 20 minutes and recorded CO by EsCCO and TTE immediately before (T0) and 5 minutes after (T1) fluid administration. Patients were divided into 2 groups (responders and non-responders) according to a threshold of 15% increase in COTTE in response to volume expansion.Results
In total, 25 patients were included, average 64±15 years, 15 (60%) were men. Average SAPSII and SOFA scores were 55±21.3 and 13±2, respectively. ICU mortality was 36%. Mean cardiac output at T0 was 5.8±1.35 L/min by esCCO and 5.27±1.17 L/min by COTTE. At T1, respective values were 6.63 ± 1.57 L/min for esCCO and 6.10±1.29 L/min for COTTE. Overall, 12 patients were classified as responders, 13 as non-responders by the reference method. A threshold of 11% increase in COesCCO was found to discriminate responders from non-responders with a sensitivity of 83% (95% CI, 0.52-0.98) and a specificity of 77% (95% CI, 0.46-0.95).Conclusion
We show strong correlation esCCO and echocardiography for measuring CO, and change in CO after fluid infusion in ICU patients. 相似文献13.
Background
Although aerobic fitness is regarded as an overall prognostic measure of morbidity and mortality, its evaluation in the chronic progressive sinopulmonary disease primary ciliary dyskinesia (PCD) has been infrequently and inconsistently reported. Here we assessed peak oxygen uptake (VO2peak) in a large well-characterized cohort of PCD patients, and explored whether VO2peak was associated with parameters of pulmonary function, self-reported physical limitations, and physical activity level.Methods
VO2peak, spirometry, diffusing capacity, whole-body plethysmography, and nitrogen multiple breath inert gas washout (N2 MBW) were assessed in a cross-sectional, single-occasion study of clinically stable children and young adults with PCD. We used a questionnaire including self-reported physical limitations in everyday life or in vigorous activities, and estimation of weekly hours of strenuous physical activity. VO2peak in PCD patients was compared with that in matched, healthy control subjects and a national reference.Results
Forty-four PCD patients aged 6–29 years exhibited reduced VO2peak compared to healthy controls (P<0.001) and the national reference. VO2peak was abnormal (z-score <–1.96) in 34% of PCD patients. Spirometric values, RV/TLC, and indices of N2 MBW were significantly abnormal, but VO2peak only correlated with FEV1 and DLCO/VA. VO2peak correlated with complaints of moderate or significant limitations in vigorous activities (P = 0.0001), exhibited by 39% of PCD patients.Conclusion
One-third of PCD patients exhibited substantially lower aerobic fitness than healthy subjects. Aerobic fitness correlated with FEV1, DLCO/VA and self-reported complaints of limitations in vigorous physical activity. These findings are most likely explained by PCD pulmonary disease and its impact on pulmonary function and physical ability. Considering fitness as an important outcome and including regular strenuous physical activity in PCD treatment would probably altogether increase pulmonary clearance, lung function, aerobic fitness, and quality of life, and prevent lifestyle-related diseases. 相似文献14.
Martin Schwaiblmair Christian Faul Wolfgang von Scheidt Thomas M Berghaus 《Respiratory research》2012,13(1):18
Background
As differences in gas exchange between pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH) have been demonstrated, we asked if cardiac output measurements determined by acetylene (C2H2) uptake significantly differed in these diseases when compared to the thermodilution technique.Method
Single-breath open-circuit C2H2 uptake, thermodilution, and cardiopulmonary exercise testing were performed in 72 PAH and 32 CTEPH patients.Results
In PAH patients the results for cardiac output obtained by the two methods showed an acceptable agreement with a mean difference of -0.16 L/min (95% CI -2.64 to 2.32 L/min). In contrast, the agreement was poorer in the CTEPH group with the difference being -0.56 L/min (95% CI -4.96 to 3.84 L/min). Functional dead space ventilation (44.5 ± 1.6 vs. 32.2 ± 1.4%, p < 0.001) and the mean arterial to end-tidal CO2 gradient (9.9 ± 0.8 vs. 4.1 ± 0.5 mmHg, p < 0.001) were significantly elevated among CTEPH patients.Conclusion
Cardiac output evaluation by the C2H2 technique should be interpreted with caution in CTEPH, as ventilation to perfusion mismatching might be more relevant than in PAH. 相似文献15.
Objective
Boluses are used in high-energy radiotherapy in order to overcome the skin sparing effect. In practice though, commonly used flat boluses fail to make a perfect contact with the irregular surface of the patient’s skin, resulting in air gaps. Hence, we fabricated a customized bolus using a 3-dimensional (3D) printer and evaluated its feasibility for radiotherapy.Methods
We designed two kinds of bolus for production on a 3D printer, one of which was the 3D printed flat bolus for the Blue water phantom and the other was a 3D printed customized bolus for the RANDO phantom. The 3D printed flat bolus was fabricated to verify its physical quality. The resulting 3D printed flat bolus was evaluated by assessing dosimetric parameters such as D1.5 cm, D5 cm, and D10 cm. The 3D printed customized bolus was then fabricated, and its quality and clinical feasibility were evaluated by visual inspection and by assessing dosimetric parameters such as Dmax, Dmin, Dmean, D90%, and V90%.Results
The dosimetric parameters of the resulting 3D printed flat bolus showed that it was a useful dose escalating material, equivalent to a commercially available flat bolus. Analysis of the dosimetric parameters of the 3D printed customized bolus demonstrated that it is provided good dose escalation and good contact with the irregular surface of the RANDO phantom.Conclusions
A customized bolus produced using a 3D printer could potentially replace commercially available flat boluses. 相似文献16.
Background
Higher serum concentrations of 25-hydroxyvitamin D (25(OH)D), an indicator of vitamin D synthesis and intake, have been associated with better mental health and cognitive function. Concentrations of 1,25-dihydroxyvitamin D3 (the active vitamin D3 metabolite) have been associated with openness and extrovert behaviour, but 25(OH)D concentrations have not been associated with behavioural problems in humans.Methods
We investigated the prospective association between the different forms of 25(OH)D - 25(OH)D3 and 25(OH)D2– and childhood behavioural problems in Avon Longitudinal Study of Parents and Children (ALSPAC). Serum 25(OH)D3 and 25(OH)D2 concentrations were assessed at mean age 9.9 years. Incident behavioural problems were assessed with Strengths and Difficulties Questionnaire (SDQ; emotional symptoms, conduct problems, hyperactivity-inattention problems, peer relationship problems and pro-social behaviour subscales and total difficulties score) at mean age 11.7. Sample sizes varied between 2413-2666 depending on the outcome.Results
Higher 25(OH)D3 concentrations were weakly associated with lower risk of prosocial problems (fully adjusted odds ratio: OR (95% confidence interval: CI) 0.85 (0.74, 0.98)). Serum 25(OH)D3 or 25(OH)D2 concentrations were not associated with other subscales of SDQ or total difficulties score after adjusting for concfounders and other measured analytes related to vitamin D.Conclusions
Our findings do not support the hypothesis that 25-hydroxyvitamin D status in childhood has important influences on behavioural traits in humans. 相似文献17.
Jordis Trischler Nick Merkel Stephanie K?nitzer Christina-Maria Müller Susanne Unverzagt Christiane Lex 《Respiratory research》2012,13(1):14
Background
Asthma is a chronic inflammatory disease of the airways but recent studies have shown that alveoli are also subject to pathophysiological changes. This study was undertaken to compare hydrogen peroxide (H2O2) concentrations in different parts of the lung using a new technique of fractioned breath condensate sampling.Methods
In 52 children (9-17 years, 32 asthmatic patients, 20 controls) measurements of exhaled nitric oxide (FENO), lung function, H2O2 in exhaled breath condensate (EBC) and the asthma control test (ACT) were performed. Exhaled breath condensate was collected in two different fractions, representing mainly either the airways or the alveoli. H2O2 was analysed in the airway and alveolar fractions and compared to clinical parameters.Results
The exhaled H2O2 concentration was significantly higher in the airway fraction than in the alveolar fraction comparing each single pair (p = 0.003, 0.032 and 0.040 for the whole study group, the asthmatic group and the control group, respectively). Asthma control, measured by the asthma control test (ACT), correlated significantly with the H2O2 concentrations in the alveolar fraction (r = 0.606, p = 0.004) but not with those in the airway fraction in the group of children above 12 years. FENO values and lung function parameters did not correlate to the H2O2 concentrations of each fraction.Conclusion
The new technique of fractionated H2O2 measurement may differentiate H2O2 concentrations in different parts of the lung in asthmatic and control children. H2O2 concentrations of the alveolar fraction may be related to the asthma control test in children. 相似文献18.
Jacqueline de Melo Barcelar Andrea Aliverti Catarina Rattes Maria Eduarda Ximenes Shirley Lima Campos Daniella Cunha Brand?o Guilherme Fregonezi Armèle Dornelas de Andrade 《PloS one》2014,9(11)
Objective
To analyze in obese women the acute effects of the breath stacking technique on thoraco-abdominal expansion.Design and Methods
Nineteen obese women (BMI≥30 kg/m2) were evaluated by anthropometry, spirometry and maximal respiratory muscle pressures and successively analyzed by Opto-Electronic Plethysmography and a Wright respirometer during quiet breathing and breath stacking maneuvers and compared with a group of 15 normal-weighted healthy women. The acute effects of the maneuvers were assessed in terms of total and compartmental chest wall volumes at baseline, end of the breath stacking maneuver and after the maneuver. Obese subjects were successively classified into two groups, accordingly to the response during the maneuver, group 1 = prevalent rib cage or group 2 = abdominal expansion.Results
Age was significantly lower in group 1 than group 2. When considering the two obese groups, FEV1 was lower and minute ventilation was higher only in group 2 compared to controls group. During breath stacking, inspiratory capacity was significant differences in obese subjects with a smaller expansion of the pulmonary rib cage and a greater expansion of the abdomen compared to controls and also between groups 1 and 2. A significant inverse linear relationship was found between age and inspiratory capacity of the pulmonary rib cage but not of the abdomen.Conclusions
In obese women the maximal expansion of the rib cage and abdomen is influenced by age and breath stacking maneuver could be a possible therapy for preventing respiratory complications. 相似文献19.
Xinyou Yin 《Annals of botany》2013,112(3):465-475
Background
Process-based ecophysiological crop models are pivotal in assessing responses of crop productivity and designing strategies of adaptation to climate change. Most existing crop models generally over-estimate the effect of elevated atmospheric [CO2], despite decades of experimental research on crop growth response to [CO2].Analysis
A review of the literature indicates that the quantitative relationships for a number of traits, once expressed as a function of internal plant nitrogen status, are altered little by the elevated [CO2]. A model incorporating these nitrogen-based functional relationships and mechanisms simulated photosynthetic acclimation to elevated [CO2], thereby reducing the chance of over-estimating crop response to [CO2]. Robust crop models to have small parameterization requirements and yet generate phenotypic plasticity under changing environmental conditions need to capture the carbon–nitrogen interactions during crop growth.Conclusions
The performance of the improved models depends little on the type of the experimental facilities used to obtain data for parameterization, and allows accurate projections of the impact of elevated [CO2] and other climatic variables on crop productivity. 相似文献20.