Stabilization of Charged Polysaccharide Film Forming Solution by Sodium Chloride: Nanoparticle Z-Average and Zeta-Potential Monitoring

Different natural biopolymers are becoming the issue of an expanding number of studies reporting their potential applications in food, pharmaceutical and cosmetic technologies, as well as in tissues engineering . In this respect, the utilization of charged polysaccharides like chitosan (CH) or pectin (PEC) appears to be one of the most interesting way in manufacturing of biodegradable new materials

Basil essential oil: Composition, antimicrobial properties, and microencapsulation to produce active chitosan films for food packaging

The essential oil (EO) from basil—Ocimum basilicum—was characterized, microencapsu-lated by vibration technology, and used to prepare a new type of packaging system designed to extend the food shelf life. The basil essential oil (BEO) chemical composition and antimicrobial activity were analyzed, as well as the morphological and biological properties of the derived BEO microcapsules (BEOMC). Analysis of BEO by gas chromatography demonstrated that the main component was linalool, whereas the study of its antimicrobial activity showed a significant inhibitory effect against all the microorganisms tested, mostly Gram-positive bacteria. Moreover, the prepared BEOMC showed a spheroidal shape and retained the EO antimicrobial activity. Finally, chitosan-based edible films were produced, grafted with BEOMC, and characterized for their physicochemical and biological properties. Since their effective antimicrobial activity was demonstrated, these films were tested as packaging system by wrapping cooked ham samples during 10 days of storage, with the aim of their possible use to extend the shelf life of the product. It was demonstrated that the obtained active film can both control the bacterial growth of the cooked ham and markedly inhibit the pH increase of the packaged food

Target identification of Mycobacterium tuberculosis phenotypic\textit{Mycobacterium tuberculosis phenotypic} hits using a concerted chemogenomic, biophysical and structural approach

Mycobacterium phenotypic hits are a good reservoir for new chemotypes for the treatment of tuberculosis. However, the absence of defined molecular targets and modes of action could lead to failure in drug development. Therefore, a combination of ligand-based and structure-based chemogenomic approaches followed by biophysical and biochemical validation have been used to identify targets for Mycobacterium tuberculosis phenotypic hits. Our approach identified EthR and InhA as targets for several hits, with some showing dual activity against these proteins. From the 35 predicted EthR inhibitors, eight exhibited an IC50 below 50 μM against M. tuberculosis EthR and three were confirmed to be also simultaneously active against InhA. Further hit validation was performed using X-ray crystallography yielding eight new crystal structures of EthR inhibitors. Although the EthR inhibitors attain their activity against M. tuberculosis by hitting yet undefined targets, these results provide new lead compounds that could be further developed to be used to potentiate the effect of EthA activated pro-drugs, such as ethionamide, thus enhancing their bactericidal effect.GM is grateful to the European Molecular Biology Laboratory and Marie Sklodowska-Curie Actions for funding this work. VM and MB acknowledge Bill & Melinda Gates Foundation [subcontract by the Foundation for the National Institutes of Health (NIH)] (OPP1024021). VM and MS acknowledge the European Community’s Seventh Framework Programme [grant number 260872]. GP would like to acknowledge the Wellcome Trust and the European Molecular Biology Laboratory for funding. JPO was funded by the member nation states of the European Molecular Biology Laboratory. TLB acknowledges The Wellcome Trust for funding and support (grant number 200814/Z/16/Z)

Prospective Validation of the Emergency Heart Failure Mortality Risk Grade for Acute Heart Failure: The ACUTE Study

Background: Improved risk stratification of acute heart failure in the emergency department may inform physicians\u27 decisions regarding patient admission or early discharge disposition. We aimed to validate the previously-derived Emergency Heart failure Mortality Risk Grade for 7-day (EHMRG7) and 30-day (EHMRG30-ST) mortality. Methods: We conducted a multicenter, prospective validation study of patients with acute heart failure at 9 hospitals. We surveyed physicians for their estimates of 7-day mortality risk, obtained for each patient before knowledge of the model predictions, and compared these with EHMRG7 for discrimination and net reclassification improvement. We also prospectively examined discrimination of the EHMRG30-ST model, which incorporates all components of EHMRG7 as well as the presence of ST-depression on the 12-lead ECG. Results: We recruited 1983 patients seeking emergency department care for acute heart failure. Mortality rates at 7 days in the 5 risk groups (very low, low, intermediate, high, and very high risk) were 0%, 0%, 0.6%, 1.9%, and 3.9%, respectively. At 30 days, the corresponding mortality rates were 0%, 1.9%, 3.9%, 5.9%, and 14.3%. Compared with physician-estimated risk of 7-day mortality (PER7; c-statistic, 0.71; 95% CI, 0.64-0.78) there was improved discrimination with EHMRG7 (c-statistic, 0.81; 95% CI, 0.75-0.87; P=0.022 versus PER7) and with EHMRG7 combined with physicians\u27 estimates (c-statistic, 0.82; 95% CI, 0.76-0.88; P=0.003 versus PER7). Model discrimination increased nonsignificantly by 0.014 (95% CI, -0.009-0.037) when physicians\u27 estimates combined with EHMRG7 were compared with EHMRG7 alone (P=0.242). The c-statistic for EHMRG30-ST alone was 0.77 (95% CI, 0.73-0.81) and 30-day model discrimination increased nonsignificantly by addition of physician-estimated risk to 0.78 (95% CI, 0.73-0.82; P=0.187). Net reclassification improvement with EHMRG7 was 0.763 (95% CI, 0.465-1.062) when assessed continuously and 0.820 (0.560-1.080) using risk categories compared with PER7. Conclusions: A clinical model allowing simultaneous prediction of mortality at both 7 and 30 days identified acute heart failure patients with a low risk of events. Compared with physicians\u27 estimates, our multivariable model was better able to predict 7-day mortality and may guide clinical decisions. Clinical Trial Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT02634762

High-frequency conductivity of optically excited charge carriers in hydrogenated nanocrystalline silicon investigated by spectroscopic femtosecond pump-probe reflectivity measurements

We report an investigation into the high-frequency conductivity of optically excited charge carriers far from equilibrium with the lattice. The investigated samples consist of hydrogenated nanocrystalline silicon films grown on a thin film of silicon oxide on top of a silicon substrate. For the investigation, we used an optical femtosecond pump-probe setup to measure the reflectance change of a probe beam. The pump beam ranged between 580 and 820nm, whereas the probe wavelength spanned 770 to 810nm. The pump fluence was fixed at 0.6mJ/cm2. We show that at a fixed delay time of 300fs, the conductivity of the excited electron-hole plasma is described well by a classical conductivity model of a hot charge carrier gas found at Maxwell-Boltzmann distribution, while Fermi-Dirac statics is not suitable. This is corroborated by values retrieved from pump-probe reflectance measurements of the conductivity and its dependence on the excitation wavelength and carrier temperature. The conductivity decreases monotonically as a function of the excitation wavelength, as expected for a nondegenerate charge carrier gas

Abnormal mitochondrial respiration in skeletal muscle in patients with peripheral arterial disease

AbstractObjectiveDiscrete morphologic, enzymatic and functional changes in skeletal muscle mitochondria have been demonstrated in patients with peripheral arterial disease (PAD). We examined mitochondrial respiration in the gastrocnemius muscle of nine patients (10 legs) with advanced PAD and in nine control patients (nine legs) without evidence of PAD.MethodsMitochondrial respiratory rates were determined with a Clark electrode in an oxygraph cell containing saponin-skinned muscle bundles. Muscle samples were obtained from the anteromedial aspect of the gastrocnemius muscle, at a level 10 cm distal to the tibial tuberosity. Mitochondria respiratory rate, calculated as nanoatoms of oxygen consumed per minute per milligram of noncollagen protein, were measured at baseline (V0), after addition of substrates (malate and glutamate; (VSUB), after addition of adenosine diphosphate (ADP) (VADP), and finally, after adenine nucleotide translocase inhibition with atractyloside (VAT). The acceptor control ratio, a sensitive indicator of overall mitochondrial function, was calculated as the ratio of the respiratory rate after the addition of ADP to the respiratory rate after adenine nucleotide translocase inhibition with atractyloside (VADP/ VAT).ResultsRespiratory rate in muscle mitochondria from patients with PAD were not significantly different from control values at baseline (0.31 ± 0.06 vs 0.55 ± 0.12; P = .09), but Vsub was significantly lower in patients with PAD compared with control subjects (0.43 ± 0.07 vs 0.89 ± 0.20; P < .05), as was VADP (0.69 ± 0.13 vs 1.24 ± 0.20; P < .05). Respiratory rates after atractyloside inhibition in patients with PAD were no different from those in control patients (0.47 ± 0.07 vs 0.45 ± P = .08). Compared with control values, mitochondria from patients with PAD had a significantly lower acceptor control ratio (1.41 ± 0.10 vs 2.90 ± 0.20; P < .001).ConclusionMitochondrial respiratory activity is abnormal in lower extremity skeletal muscle in patients with PAD. When considered in concert with the ultrastructural and enzymatic abnormalities previously documented in mitochondria of chronically ischemic muscle, these data support the concept of defective mitochondrial function as a pathophysiologic component of PAD

The Buffer Gas Beam: An Intense, Cold, and Slow Source for Atoms and Molecules

Beams of atoms and molecules are stalwart tools for spectroscopy and studies of collisional processes. The supersonic expansion technique can create cold beams of many species of atoms and molecules. However, the resulting beam is typically moving at a speed of 300-600 m/s in the lab frame, and for a large class of species has insufficient flux (i.e. brightness) for important applications. In contrast, buffer gas beams can be a superior method in many cases, producing cold and relatively slow molecules in the lab frame with high brightness and great versatility. There are basic differences between supersonic and buffer gas cooled beams regarding particular technological advantages and constraints. At present, it is clear that not all of the possible variations on the buffer gas method have been studied. In this review, we will present a survey of the current state of the art in buffer gas beams, and explore some of the possible future directions that these new methods might take