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941.
Fast, cheap, and easy to implement point-of-care testing for various pathogens constituted a game changer in past years due to its potential for early disease diagnosis. Herein, we report on the proof-of-concept of a simple method enabling in vitro detection of a structural spike protein subunit from the SARS-CoV-2 (S1) in aqueous samples. At the core of this discovery lies the well-known paradigm of monitoring the capacitive current across a reconstituted zwitterionic lipid membrane subjected to a periodic transmembrane potential, followed by the real-time spectral analysis enabling the extraction of the second harmonic of the capacitive current. Subsequent changes in the amplitude of this harmonic recorded during lipid membrane–S1 interactions were correlated with alterations induced in the inner membrane potential profile by the S1 protein subunit adsorption, and were shown to be augmented by ionic strength, the presence of a specific monoclonal antibody designed against the S1 subunit and the angiotensin-converting enzyme 2 (ACE2) protein receptor, and uninhibited by the presence of other human serum proteins.  相似文献   
942.

Inbreeding can have negative effects on survival and reproduction, which may be of conservation concern in small and isolated populations. However, the physiological mechanisms underlying inbreeding depression are not well-known. The length of telomeres, the DNA sequences protecting chromosome ends, has been associated with health or fitness in several species. We investigated effects of inbreeding on early-life telomere length in two small island populations of wild house sparrows (Passer domesticus) known to be affected by inbreeding depression. Using genomic measures of inbreeding we found that inbred nestling house sparrows (n?=?371) have significantly shorter telomeres. Using pedigree-based estimates of inbreeding we found a tendency for inbred nestling house sparrows to have shorter telomeres (n?=?1195). This negative effect of inbreeding on telomere length may have been complemented by a heterosis effect resulting in longer telomeres in individuals that were less inbred than the population average. Furthermore, we found some evidence of stronger effects of inbreeding on telomere length in males than females. Thus, telomere length may reveal subtle costs of inbreeding in the wild and demonstrate a route by which inbreeding negatively impacts the physiological state of an organism already at early life-history stages.

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Human male height is one of the most conspicuous sexually dimorphic, phenotypic characteristics that affect how men are perceived both by men and women, impacting mate selection and intra-sexual competition. Testosterone is a key hormone linked to morphological masculinity and advantage in intra-sexual competition. To date, there have been limited studies linking height with testosterone levels. Here, we examined the change in circulating testosterone levels after physical exercise in 97 healthy and physically active men. Our results show that there was a significant relationship between male stature and the change in testosterone levels, whereas there was no such link between body height and circulating testosterone levels. Therefore, our findings provide evidence that height may indicate male’s adaptive capabilities to physiologically mobilize their bodies when it is needed and/or beneficial.  相似文献   
947.
A modular dendrimer-based drug delivery platform was designed to improve upon existing limitations in single dendrimer systems. Using this modular strategy, a biologically active platform containing receptor mediated targeting and fluorescence imaging modules was synthesized by coupling a folic acid (FA) conjugated dendrimer with a fluorescein isothiocyanate (FITC) conjugated dendrimer. The two different dendrimer modules were coupled via the 1,3-dipolar cycloaddition reaction ("click" chemistry) between an alkyne moiety on the surface of the first dendrimer and an azide moiety on the second dendrimer. Two simplified model systems were also synthesized to develop appropriate "click" reaction conditions and aid in spectroscopic assignments. Conjugates were characterized by (1)H NMR spectroscopy and NOESY. The FA-FITC modular platform was evaluated in vitro with a human epithelial cancer cell line (KB) and found to specifically target the overexpressed folic acid receptor.  相似文献   
948.
Arginase constrains endothelial nitric oxide synthase activity by competing for the common substrate, L -Arginine. We have recently shown that inducible nitric oxide synthase (NOS2) S-nitrosates and activates arginase 1 (Arg1) leading to age-associated vascular dysfunction. Here, we demonstrate that a direct interaction of Arg1 with NOS2 is necessary for its S-nitrosation. The specific domain of NOS2 that mediates this interaction is identified. Disruption of this interaction in human aortic endothelial cells prevents Arg1 S-nitrosation and activation. Thus, disruption of NOS2-Arg1 interaction may represent a therapeutic strategy to attenuate age related vascular endothelial dysfunction.  相似文献   
949.
The aim of the study was to evaluate the antifungal activity of a new triazole formulation against 182 clinical isolates of yeasts recovered from blood cultures in three tertiary hospitals in Romania and to compare its activity with those of fluconazole and voriconazole. In vitro susceptibility was assessed by following the guidelines of AFST-EUCAST E. Def. 7.1. The distribution of minimum inhibitory concentrations (MICs) of MXP-4509 was very similar to that of voriconazole (MIC50: 0.0312 mg/l vs. 0.0156 mg/l; MIC90: 0.25 mg/l vs. 0.25 mg/l), but significantly different from that of fluconazole (MIC50: 0.0312 mg/l vs. 0.5 mg/l; MIC90: 0.25 mg/l vs. 32 mg/l). The new triazole MXP-4509 proved to have a good in vitro antifungal activity raising the interest for further pharmacological and microbiological investigations in order to assess its potential advantages for therapy.  相似文献   
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