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571.
UV radiation, in particular UVB, suppresses the skin immune response. In patients with polymorphous light eruption (PLE) the skin immune response seems activated after UV exposure. Typical PLE skin lesions can occur as early as several hours after UV exposure. In healthy volunteers, neutrophils infiltrate the skin shortly after UV exposure. The kinetics and mechanisms of neutrophil infiltration in the skin of PLE patients after UVB exposure was studied. Skin biopsies at 0, 3, 6, and 18 h were taken from five PLE patients and six healthy controls after irradiation with three minimal erythema dose UVB. Furthermore, neutrophils were isolated from blood of five PLE patients and six healthy controls to test their chemotactic activity. Immunohistochemical analysis showed a significant decreased neutrophil infiltration in PLE skin after UVB irradiation compared with healthy controls (p<0.05). In both healthy controls and PLE patients, after UVB irradiation, ICAM-1 and E-selectin expression on endothelial cells increased at 6 h after irradiation. Blood neutrophil chemotactic response towards IL-8 and C5a, as well as the expression of cell surface markers involved in adhesion and chemotaxis, was not different between PLE patients and healthy controls. In conclusion, PLE is marked by a decreased skin infiltration of neutrophils after UVB irradiation, possibly leading to a diminished neutrophil-induced suppression.  相似文献   
572.
573.
The incidence of fetal breathing was studied during the course of behavioral state observations on 28 low-risk fetuses between 32 and 40 weeks' gestational age and on 12 growth-retarded fetuses between 36 and 40 weeks. Real-time ultrasound scanners were used to detect fetal eye, body, and breathing movements, and the fetal heart rate was recorded continuously. The mean duration of the observation sessions was 110 minutes. The mean incidence of fetal breathing was greater during periods of fetal activity (body and eye movements present, greater heart rate variability) than during quiescence (body and eye movements absent, narrowed heart rate variability) at all gestational ages studied in both low-risk and growth-retarded fetuses. During periods when one of the state variables (body movements, eye movements, heart rate pattern) was in its active condition while the other two were quiet, or the reverse, the incidence of fetal breathing was intermediate between those found when all three state variables were in agreement. After behavioral states had developed, at 38 and 40 weeks, the mean incidence of fetal breathing in the low-risk fetuses was greater during active states than during the quiet state. There was no apparent increase in the degree of linkage between fetal breathing and other expressions of fetal activity after the emergence of behavioral states.  相似文献   
574.
Autoimmunity as an aetiological factor in vitiligo   总被引:2,自引:0,他引:2  
Vitiligo is a common dermatological disorder characterized by the presence on the skin of depigmented macules resulting from the destruction of cutaneous melanocytes. Autoimmunity is an important hypothesis with regard to vitiligo aetiology and the evidence for autoimmune responses being involved in the pathogenesis of this disorder will be discussed in the present review. All immune system compartments, including innate and adaptive immunity have been implicated in vitiligo development. Particularly relevant are autoantibodies and autoreactive T cells in vitiligo patients that have cytotoxic effects upon pigment cells. Furthermore, predisposition to vitiligo appears to be associated with certain alleles of the major histocompatibility complex class II antigens as well as with other autoimmune-susceptibility genes. Moreover, the association of vitiligo with autoimmune disorders, the animal models of the disease, and the positive response to immunosuppressive therapeutic agents emphasize the role of autoimmunity in the development of this disorder.  相似文献   
575.

Background  

Asthma is the most common chronic disease in childhood, characterized by chronic airway inflammation. There are problems with the diagnosis of asthma in young children since the majority of the children with recurrent asthma-like symptoms is symptom free at 6 years, and does not have asthma. With the conventional diagnostic tools it is not possible to differentiate between preschool children with transient symptoms and children with asthma. The analysis of biomarkers of airway inflammation in exhaled breath is a non-invasive and promising technique to diagnose asthma and monitor inflammation in young children. Moreover, relatively new lung function tests (airway resistance using the interrupter technique) have become available for young children. The primary objective of the ADEM study (Asthma DEtection and Monitoring study), is to develop a non-invasive instrument for an early asthma diagnosis in young children, using exhaled inflammatory markers and early lung function measurements. In addition, aetiological factors, including gene polymorphisms and gene expression profiles, in relation to the development of asthma are studied.  相似文献   
576.

Background

Gastroesophageal reflux disease (GERD) is one of the most prevalent gastrointestinal diseases in the western world. Lifestyle modifications and proton pump inhibitors (PPIs) form the basis of the management of GERD. A subset of patients seeks for (natural) alternative therapies besides PPIs. benesco™ is an over-the-counter nutrition based on quercetin which has a presumed positive effect on esophageal barrier function. Therefore we aim to assess the effect of benesco™ on reflux symptoms.

Methods

We performed a double-blind randomized placebo-controlled trial in participants with reflux symptoms. Participants were assigned randomly (1:1) to receive 6 weeks of benesco™ (three times daily one lozenge containing 200 mg of quercetin) or placebo. The primary outcome was treatment success (≥50% reduction in Reflux Disease Questionnaire Score). Secondary outcomes included GERD-related quality of life, reflux-free days and nights, and participant-reported treatment success.

Key Results

One hundred participants were randomized. Treatment success was seen in 18 (39%) of 46 participants in the intervention group versus 21 (47%) of 45 in the placebo group (p = 0.468). In the intervention group 10 (1–21) reflux-free days were reported compared to 10 (2–25) in the placebo group (p = 0.673). In addition, 38 (34–41) versus 39 (35–42) reflux-free nights were reported (p = 0.409).

Conclusions & Inferences

In our trial benesco™ showed no significant benefit over placebo at group level.  相似文献   
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