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A rise in the number of flood-affected people and areas has increased the interest in new methods and concepts that account for this change.Citizens are inte-gr...  相似文献   
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Respiratory viruses play an important role in asthma exacerbation, and early exposure can be involved in recurrent bronchitis and the development of asthma. The exact mechanism is not fully clarified, and pathogen-to-host interaction studies are warranted to identify biomarkers of exacerbation in the early phase. Only a limited number of international exacerbation cohorts were studied. Here, we have established a local pediatric exacerbation study in Germany consisting of children with asthma or chronic, recurrent bronchitis and analyzed the viriome within the nasopharyngeal swab specimens derived from the entire cohort (n = 141). Interestingly, 41% of exacerbated children had a positive test result for human rhinovirus (HRV)/human enterovirus (HEV), and 14% were positive for respiratory syncytial virus (RSV). HRV was particularly prevalent in asthmatics (56%), wheezers (50%), and atopic (66%) patients. Lymphocytes were decreased in asthmatics and in HRV-infected subjects, and patients allergic to house dust mites were more susceptible to HRV infection. Our study thus confirms HRV infection as a strong ‘biomarker’ of exacerbated asthma. Further longitudinal studies will show the clinical progress of those children with a history of an RSV or HRV infection. Vaccination strategies and novel treatment guidelines against HRV are urgently needed to protect those high-risk children from a serious course of disease.  相似文献   
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Journal für Ästhetische Chirurgie - Fett bietet neben seinem volumisierenden Effekt ein reichhaltiges Reservoir für regenerative Zellen, die eine wichtige Rolle für den Einbau...  相似文献   
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We report the first phase I trial to assess the safety and immunogenicity of a malaria vaccine candidate, ICC-1132 (Malarivax), composed of a modified hepatitis B virus core protein (HBc) containing minimal epitopes of the Plasmodium falciparum circumsporozoite (CS) protein. When expressed in Escherichia coli, the recombinant ICC-1132 protein forms virus-like particles that were found to be highly immunogenic in preclinical studies of mice and monkeys. Twenty healthy adult volunteers received a 20- or a 50-microg dose of alum-adsorbed ICC-1132 administered intramuscularly at 0, 2, and 6 months. The majority of volunteers in the group receiving the 50-microg dose developed antibodies to CS repeats as well as to HBc. Malaria-specific T cells that secreted gamma interferon were also detected after a single immunization with ICC-1132-alum. These studies support ICC-1132 as a promising malaria vaccine candidate for further clinical testing using more-potent adjuvant formulations and confirm the potential of modified HBc virus-like particles as a delivery platform for vaccines against other human pathogens.  相似文献   
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Conversion of the biophysically active large surfactant aggregate subtype (LA) of alveolar surfactant into the less surface active small surfactant aggregates (SA) occurs in vivo and is reproduced under conditions of cyclic surface area changes in vitro. A serine-active carboxyl esterase has been suggested as the responsible enzymatic activity, although the exact mechanisms underlying the conversion process are presently unclear. We investigated the influence of exogenous serine proteases and synthetic and natural serine protease inhibitors on the conversion kinetics of natural rabbit surfactant, obtained as bronchoalveolar lavage fluid (BALF). In vitro cycling of BALF was performed for various time periods in the absence or presence of increasing amounts of several serine proteases (trypsin, plasmin, thrombin, tryptase), and one natural (aprotinin) and 25 synthetic serine protease inhibitors (including regular benzamidines [group A], 3-amidinophenylalanine derivatives [group B], bis-benzamidines [group C], and analogs of naphthylsulfonyl-glycyl-4-amidinophenylalanine piperidide [group D]). LA were separated from SA by 48,000 x g centrifugation. Surface activity of the LA fraction was measured by means of the pulsating bubble surfactometer. None of the "classical" serine proteases forwarded any acceleration of the LA-to-SA conversion kinetics. Some of the serine protease inhibitors caused moderate retardation of conversion, but at the same dose range inhibited the surface tension-lowering properties of the LA fraction, which per se explained their inhibitory effect. In contrast, specific dose-dependent inhibition of the LA-to-SA transition was observed for four derivatives of the bis-benzamidine group: full blockage of conversion over 240 min of cycling was noted at doses that did not interfere with the surface activity of the LA fraction. In addition, the prototype of these bis-benzamidines, 1,4-bis-[beta-naphthylsulfonyl-(3-aminophenylalanine)]-piperazide, was found to inhibit the activity of the rabbit liver carboxylesterase ES-2 in two different synthetic substrate assays reflecting the amidase and esterase properties of carboxylesterases. These findings support the hypothesis that the LA-to-SA conversion is an enzymatically-driven process with serine-active carboxyl esterase(s) being centrally involved. Synthetic bis-benzamidine-type serine protease inhibitors may offer specific inhibition of this event.  相似文献   
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In the present study, surface-modified nanoparticles based on biodegradable material were used for antibody coupling in order to get a selective drug carrier systems. Gelatin nanoparticles were prepared by a desolvation process. Sulfhydryl groups were introduced which enabled the linkage of NeutrAvidin (NAv). Antibodies specific for the CD3 antigen on lymphocytic cells were conjugated to the nanoparticles surface. The binding of biotinylated anti-CD3 antibody was achieved by NAv-biotin-complex formation. Cellular binding and uptake were determined by flow cytometry and confocal laser scanning microscopy (CLSM). Cell-type-specific targeting of anti-CD3-conjugated nanoparticles into CD3-positive human T-cell leukemia cells and primary T-lymphocytes could be shown. Celluar uptake and effective internalization of antibody-conjugated nanoparticles into CD3 expressing cells were demonstrated. Uptake rates of about 84% into T-cell leukemia cells were observed. To confirm selectivity of T-cell targeting, competition experiments were carried out adding excessive free anti-CD3 prior to nanoparticle incubation leading to significantly reduced cellular uptake of antibody-conjugated nanoparticles. Further analysis on the mechanism of uptake confirmed a receptor-mediated endocytotic process. Protein-based nanoparticles conjugated with an antibody against a specific cellular antigen hold promise as selective drug delivery systems for specific cell types.  相似文献   
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