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31.

Background

The aim of the study was to investigate how the expression of adhesion molecules changes as neutrophils migrate from the circulation to the lung and if these changes differ between non-smoking subjects and smokers with and without COPD.

Methods

Non-smoking healthy subjects (n=22), smokers without (n=21) and with COPD (n=18) were included. Neutrophils from peripheral blood, sputum and bronchial biopsies were analysed for cell surface expression of adhesion molecules (CD11b, CD62L, CD162). Serum, sputum supernatant and BAL-fluid were analysed for soluble adhesion molecules (ICAM-1, -3, E-selectin, P-selectin, VCAM-1, PECAM-1).

Results

Expression of CD11b was increased on circulating neutrophils from smokers with COPD. It was also increased on sputum neutrophils in both smokers groups, but not in non-smokers, as compared to circulating neutrophils.Serum ICAM-1 was higher in the COPD group compared to the other two groups (p<0.05) and PECAM-1 was lower in smokers without COPD than in non-smoking controls and the COPD group (p<0.05). In BAL-fluid ICAM-1 was lower in the COPD group than in the other groups (p<0.05).

Conclusions

Thus, our data strongly support the involvement of a systemic component in COPD and demonstrate that in smokers neutrophils are activated to a greater extent at the point of transition from the circulation into the lungs than in non-smokers.  相似文献   
32.

Background

A major barrier to improving perinatal mental health in Africa is the lack of locally validated tools for identifying probable cases of perinatal depression or for measuring changes in depression symptom severity. We systematically reviewed the evidence on the reliability and validity of instruments to assess perinatal depression in African settings.

Methods and Findings

Of 1,027 records identified through searching 7 electronic databases, we reviewed 126 full-text reports. We included 25 unique studies, which were disseminated in 26 journal articles and 1 doctoral dissertation. These enrolled 12,544 women living in nine different North and sub-Saharan African countries. Only three studies (12%) used instruments developed specifically for use in a given cultural setting. Most studies provided evidence of criterion-related validity (20 [80%]) or reliability (15 [60%]), while fewer studies provided evidence of construct validity, content validity, or internal structure. The Edinburgh postnatal depression scale (EPDS), assessed in 16 studies (64%), was the most frequently used instrument in our sample. Ten studies estimated the internal consistency of the EPDS (median estimated coefficient alpha, 0.84; interquartile range, 0.71-0.87). For the 14 studies that estimated sensitivity and specificity for the EPDS, we constructed 2 x 2 tables for each cut-off score. Using a bivariate random-effects model, we estimated a pooled sensitivity of 0.94 (95% confidence interval [CI], 0.68-0.99) and a pooled specificity of 0.77 (95% CI, 0.59-0.88) at a cut-off score of ≥9, with higher cut-off scores yielding greater specificity at the cost of lower sensitivity.

Conclusions

The EPDS can reliably and validly measure perinatal depression symptom severity or screen for probable postnatal depression in African countries, but more validation studies on other instruments are needed. In addition, more qualitative research is needed to adequately characterize local understandings of perinatal depression-like syndromes in different African contexts.  相似文献   
33.
34.

Background

Schistosoma (S.) haematobium infection is a common cause of genital morbidity in adult women. Ova in the genital mucosal lining may cause lesions, bleeding, pain, discharge, and the damaged surfaces may pose a risk for HIV. In a heterogeneous schistosomiasis endemic area in South Africa, we sought to investigate if young girls had genital symptoms and if this was associated with urinary S. haematobium.

Methodology

In a cross-sectional study of 18 randomly chosen primary schools, we included 1057 schoolgirls between the age of 10 and 12 years. We interviewed assenting girls, whose parents had consented to their participation and examined three urines from each of them for schistosome ova.

Principal findings

One third of the girls reported to have a history of genital symptoms. Prior schistosomal infection was reported by 22% (226/1020), this was associated with current genital symptoms (p<0.001). In regression analysis the genital symptoms were significantly associated both with urinary schistosomiasis (p<0.001) and water contact (p<0.001).

Conclusions

Even before sexually active age, a relatively large proportion of the participating girls had similar genital symptoms to those reported for adult genital schistosomiasis previously. Anti-schistosomal treatment should be considered at a young age in order to prevent chronic genital damage and secondary infections such as HIV, sexually transmitted diseases and other super-infections.  相似文献   
35.
36.

Purpose

To demonstrate a method of generating patient-specific, biologically-guided radiotherapy dose plans and compare them to the standard-of-care protocol.

Methods and Materials

We integrated a patient-specific biomathematical model of glioma proliferation, invasion and radiotherapy with a multiobjective evolutionary algorithm for intensity-modulated radiation therapy optimization to construct individualized, biologically-guided plans for 11 glioblastoma patients. Patient-individualized, spherically-symmetric simulations of the standard-of-care and optimized plans were compared in terms of several biological metrics.

Results

The integrated model generated spatially non-uniform doses that, when compared to the standard-of-care protocol, resulted in a 67% to 93% decrease in equivalent uniform dose to normal tissue, while the therapeutic ratio, the ratio of tumor equivalent uniform dose to that of normal tissue, increased between 50% to 265%. Applying a novel metric of treatment response (Days Gained) to the patient-individualized simulation results predicted that the optimized plans would have a significant impact on delaying tumor progression, with increases from 21% to 105% for 9 of 11 patients.

Conclusions

Patient-individualized simulations using the combination of a biomathematical model with an optimization algorithm for radiation therapy generated biologically-guided doses that decreased normal tissue EUD and increased therapeutic ratio with the potential to improve survival outcomes for treatment of glioblastoma.  相似文献   
37.
Aim was to elucidate autonomic responses to dynamic and static (isometric) exercise of the lower limbs eliciting the same moderate heart rate (HR) response. Method: 23 males performed two kinds of voluntary exercise in a supine position at similar heart rates: static exercise (SE) of the lower limbs (static leg press) and dynamic exercise (DE) of the lower limbs (cycling). Subjective effort, systolic (SBP) and diastolic blood pressure (DBP), mean arterial pressure (MAP), rate pressure product (RPP) and the time between consecutive heart beats (RR-intervals) were measured. Time-domain (SDNN, RMSSD), frequency-domain (power in the low and high frequency band (LFP, HFP)) and geometric measures (SD1, SD2) as well as non-linear measures of regularity (approximate entropy (ApEn), sample entropy (SampEn) and correlation dimension D2) were calculated. Results: Although HR was similar during both exercise conditions (88±10 bpm), subjective effort, SBP, DBP, MAP and RPP were significantly enhanced during SE. HRV indicators representing overall variability (SDNN, SD 2) and vagal modulated variability (RMSSD, HFP, SD 1) were increased. LFP, thought to be modulated by both autonomic branches, tended to be higher during SE. ApEn and SampEn were decreased whereas D2 was enhanced during SE. It can be concluded that autonomic control processes during SE and DE were qualitatively different despite similar heart rate levels. The differences were reflected by blood pressure and HRV indices. HRV-measures indicated a stronger vagal cardiac activity during SE, while blood pressure response indicated a stronger sympathetic efferent activity to the vessels. The elevated vagal cardiac activity during SE might be a response mechanism, compensating a possible co-activation of sympathetic cardiac efferents, as HR and LF/HF was similar and LFP tended to be higher. However, this conclusion must be drawn cautiously as there is no HRV-marker reflecting “pure” sympathetic cardiac activity.  相似文献   
38.
Botulinum neurotoxin (BoNT) is a potent and potentially lethal bacterial toxin that binds to host motor neurons, is internalized into the cell, and cleaves intracellular proteins that are essential for neurotransmitter release. BoNT is comprised of a heavy chain (HC), which mediates host cell binding and internalization, and a light chain (LC), which cleaves intracellular host proteins essential for acetylcholine release. While therapies that inhibit toxin binding/internalization have a small time window of administration, compounds that target intracellular LC activity have a much larger time window of administrations, particularly relevant given the extremely long half-life of the toxin. In recent years, small molecules have been heavily analyzed as potential LC inhibitors based on their increased cellular permeability relative to larger therapeutics (peptides, aptamers, etc.). Lead identification often involves high-throughput screening (HTS), where large libraries of small molecules are screened based on their ability to modulate therapeutic target function. Here we describe a FRET-based assay with a commercial BoNT/A LC substrate and recombinant LC that can be automated for HTS of potential BoNT inhibitors. Moreover, we describe a manual technique that can be used for follow-up secondary screening, or for comparing the potency of several candidate compounds.  相似文献   
39.
For bottom‐up proteomics, there are wide variety of database‐searching algorithms in use for matching peptide sequences to tandem MS spectra. Likewise, there are numerous strategies being employed to produce a confident list of peptide identifications from the different search algorithm outputs. Here we introduce a grid‐search approach for determining optimal database filtering criteria in shotgun proteomics data analyses that is easily adaptable to any search. Systematic Trial and Error Parameter Selection‐–referred to as STEPS‐–utilizes user‐defined parameter ranges to test a wide array of parameter combinations to arrive at an optimal “parameter set” for data filtering, thus maximizing confident identifications. The benefits of this approach in terms of numbers of true‐positive identifications are demonstrated using datasets derived from immunoaffinity‐depleted blood serum and a bacterial cell lysate, two common proteomics sample types.  相似文献   
40.
Oxygen minimum zones (OMZs) affect distribution patterns, community structure and metabolic processes of marine organisms. Due to the prominent role of zooplankton, especially copepods, in the marine carbon cycle and the predicted intensification and expansion of OMZs, it is essential to understand the effects of hypoxia on zooplankton distribution and ecophysiology. For this study, calanoid copepods were sampled from different depths (0–1800 m) at eight stations in the eastern tropical Atlantic (3°47′N to 18°S) during three expeditions in 2010 and 2011. Their horizontal and vertical distribution was determined and related to the extent and intensity of the OMZ, which increased from north to south with minimum O2 concentrations (12.7 µmol kg−1) in the southern Angola Gyre. Calanoid copepod abundance was highest in the northeastern Angola Basin and decreased towards equatorial regions as well as with increasing depth. Maximum copepod biodiversity was observed in the deep waters of the central Angola Basin. Respiration rates and enzyme activities were measured to reveal species-specific physiological adaptations. Enzyme activities of the electron transport system (ETS) and lactate dehydrogenase (LDH) served as proxies for aerobic and anaerobic metabolic activity, respectively. Mass-specific respiration rates and ETS activities decreased with depth of occurrence, consistent with vertical changes in copepod body mass and ambient temperature. Copepods of the families Eucalanidae and Metridinidae dominated within the OMZ. Several of these species showed adaptive characteristics such as lower metabolic rates, additional anaerobic activity and diel vertical migration that enable them to successfully inhabit hypoxic zones.  相似文献   
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