Application of flow cytometry for the assessment of preservation and recovery efficiency of bioaerosol samplers spiked with Pantoea agglomerans

Exposure assessment of biological aerosols requires trade-offs between efficient sampling of airborne microorganisms as either particles or viable units. The main objective of this work was to characterize aspects of bioaerosol measurement efficiency. A known concentration of the vegetative bacteria Pantoea agglomerans was spiked onto different samplers (AGI-30, BioSampler, and membrane filters) and then run for increasing time periods using HEPA filtered air. Measurement efficiency was evaluated based on total, viable, and culturable counts. Total and viable counts were determined by flow-cytometry (FCM); culturable counts were evaluated by standard plating. FCM as a method for assaying viability showed excellent agreement with known proportions of live/dead organisms (slope = 0.82, R(2) = 0.99). P. agglomerans recoveries (total, viable, and culturable) in order of best sampler performance included the BioSampler (75%, 52%, and 50%), filtration (50%, 13%, and 2%), and the AGI-30 (<30%, 15%, and 5%). The difference between viability and culturability provided an indication of viable but nonculturable (VBNC) cells. VBNC efficiency for sampling by filter, AGI-30, and BioSampler was 80%, 50%, and 100%, respectively. This research helps characterize recovery, survival, and culturability efficiencies while sampling environmentally sensitive airborne bacteria for purposes of exposure assessment, epidemiologic studies, and homeland security.     

Allicin as a Volatile or Nebulisable Antimycotic for the Treatment of Pulmonary Mycoses: In Vitro Studies Using a Lung Flow Test Rig

Fungal infections of the lung are an increasing problem worldwide and the search for novel therapeutic agents is a current challenge due to emerging resistance to current antimycotics. The volatile defence substance allicin is formed naturally by freshly injured garlic plants and exhibits broad antimicrobial potency. Chemically synthesised allicin was active against selected fungi upon direct contact and via the gas phase at comparable concentrations to the pharmaceutically used antimycotic amphotericin B. We investigated the suppression of fungal growth by allicin vapour and aerosols in vitro in a test rig at air flow conditions mimicking the human lung. The effect of allicin via the gas phase was enhanced by ethanol. Our results suggest that allicin is a potential candidate for development for use in antifungal therapy for lung and upper respiratory tract infections.     

Combined Therapy with a CCR2/CCR5 Antagonist and FGF21 Analogue Synergizes in Ameliorating Steatohepatitis and Fibrosis

(1) Background: With new potential drug targets emerging, combination therapies appear attractive to treat non-alcoholic steatohepatitis (NASH) and fibrosis. Chemokine receptor CCR2/5 antagonists can improve fibrosis by reducing monocyte infiltration and altering hepatic macrophage subsets. Fibroblast growth factor 21 (FGF21) may improve NASH by modulating lipid and glucose metabolism. We compared effects of single drug to combination treatment as therapeutic strategies against NASH. (2) Methods: We analyzed serum samples and liver biopsies from 85 nonalcoholic fatty liver disease (NAFLD) patients. A CCR2/5 inhibitor (BMS-687681-02-020) and a pegylated FGF21 agonist (BMS-986171) were tested in male C57BL/6J mice subjected to dietary models of NASH and fibrosis (choline-deficient, L-amino acid-defined, high-fat diet (CDAHFD) up to 12 weeks; short- (2w) or long-term (6w) treatment). (3) Results: In NAFLD patients, chemokine CCL2 and FGF21 serum levels correlated with inflammatory serum markers, only CCL2 was significantly associated with advanced liver fibrosis. In rodent NASH, CCR2/5 inhibition significantly reduced circulating Ly6C+ monocytes and hepatic monocyte-derived macrophages, alongside reduced hepatic inflammation and fibrosis. FGF21 agonism decreased body weight, liver triglycerides and histological NASH activity. Combination treatment reflected aspects of both compounds upon short- and long-term application, thereby amplifying beneficial effects on all aspects of steatohepatitis and fibrosis. (4) Conclusions: CCR2/5 inhibition blocks hepatic infiltration of inflammatory monocytes, FGF21 agonism improves obesity-related metabolic disorders. Combined therapy ameliorates steatohepatitis and fibrosis more potently than single drug treatment in rodent NASH, corroborating the therapeutic potential of combining these two approaches in NASH patients.     

Novel Nickel(II), Palladium(II), and Platinum(II) Complexes with O,S Bidendate Cinnamic Acid Ester Derivatives: An In Vitro Cytotoxic Comparison to Ruthenium(II) and Osmium(II) Analogues

(1) Background: Since the discovery of cisplatin’s cytotoxic properties, platinum(II) compounds have attracted much interest in the field of anticancer drug development. Over the last few years, classical structure–activity relationships (SAR) have been broken by some promising new compounds based on platinum or other metals. We focus on the synthesis and characterization of 17 different complexes with β-hydroxydithiocinnamic acid esters as O,S bidendate ligands for nickel(II), palladium(II), and platinum(II) complexes. (2) Methods: The bidendate compounds were synthesized and characterized using classical methods including NMR spectroscopy, MS spectrometry, elemental analysis, and X-ray crystallography, and their cytotoxic potential was assessed using in vitro cell culture assays. Data were compared with other recently reported platinum(II), ruthenium(II), and osmium(II) complexes based on the same main ligand system. (3) Results: SAR analyses regarding the metal ion (M), and the alkyl-chain position (P) and length (L), revealed the following order of the effect strength for in vitro activity: M > P > L. The highest activities have Pd complexes and ortho-substituted compounds. Specific palladium(II) complexes show lower IC₅₀ values compared to cisplatin, are able to elude cisplatin resistance mechanisms, and show a higher cancer cell specificity. (4) Conclusion: A promising new palladium(II) candidate (Pd3) should be evaluated in further studies using in vivo model systems, and the identified SARs may help to target platinum-resistant tumors.     

Renewable energy in India: Historical developments and prospects

Promoting renewable energy in India has assumed great importance in recent years in view of high growth rate of energy consumption, high share of coal in domestic energy demand, heavy dependence on imports for meeting demands for petroleum fuels and volatility of world oil market. A number of renewable energy technologies (RETs) are now well established in the country. The technology that has achieved the most dramatic growth rate and success is wind energy; India ranks fourth in the world in terms of total installed capacity. India hosts the world's largest small gasifier programme and second largest biogas programme. After many years of slow growth, demand for solar water heaters appears to be gaining momentum. Small hydro has been growing in India at a slow but steady pace. Installation of some of the technologies appears to have slowed down in recent years; these include improved cooking stoves (ICSs) and solar photovoltaic (PV) systems. In spite of many successes, the overall growth of renewable energy in India has remained rather slow. A number of factors are likely to boost the future prospects of renewable energy in the country; these include global pressure and voluntary targets for greenhouse gas emission reduction, a possible future oil crisis, intensification of rural electrification program, and import of hydropower from neighbouring countries.     

Impact of climate policy uncertainty on the adoption of electricity generating technologies

This paper presents a real options model where multiple options are evaluated simultaneously so that the effect of the individual options on each other is accounted for. We apply this model to the electricity sector, where we analyze three typical technologies based on fossil fuel, fossil fuel with carbon capture and renewable energy, respectively. In this way, we can analyze the transition from CO₂-intensive to CO₂-neutral electricity production in the face of rising and uncertain CO₂ prices. In addition, such a modelling approach enables us to estimate precisely the expected value of (perfect) information, i.e. the willingness of investors and producers to pay for information about the correct CO₂ price path. As can be expected, the expected value of information rises with increasing CO₂ price uncertainty. In addition, the larger the price uncertainty, the larger are the cumulative CO₂ emissions over the coming century. The reason for this is that the transition to less CO₂-intensive technologies is increasingly postponed with rising CO₂ price uncertainty. By testing different price processes (geometric Brownian motion versus jump processes with different jump frequencies), we can also make useful recommendations concerning the importance of policy predictability. We find that it is better to have climate change policies that are stable over a certain length of time and change abruptly than less abrupt but more frequently changing policies. Less frequent fluctuations reduce the expected value of information and result in smaller cumulative CO₂ emissions.     

Hydridic,thermodynamic and kinetic properties of Hf2Ni intermetallic phase

The intermetallic compound Hf₂Ni was the subject of investigations by several methods. The relative stability was checked by calculating its enthalpy and cohesive properties, using the augmented plane wave plus local orbitals (APW + lo) method of ab initio calculations. The kinetics of hydrogen absorption in this compound was investigated in the temperature range from 573 to 823 K, under the constant hydrogen pressure of 1 bar. The obtained rate constants, k (s^?1), and hydriding capacities (H/M) are as follows: 0.00038 (0.69), 0.00131 (0.95), 0.00246 (1.13) and 0.0042 (0.92) for temperatures 573, 673, 723 and 823 K, respectively. The changes in crystal structure and morphology caused by multiple hydriding/dehydriding cycles were followed by XRD and SEM.     

Agent-based simulations for protecting nursing homes with prevention and vaccination strategies

Due to its high lethality among older people, the safety of nursing homes has been of central importance during the COVID-19 pandemic. With test procedures and vaccines becoming available at scale, nursing homes might relax prohibitory measures while controlling the spread of infections. By control we mean that each index case infects less than one other person on average. Here, we develop an agent-based epidemiological model for the spread of SARS-CoV-2 calibrated to Austrian nursing homes to identify optimal prevention strategies. We find that the effectiveness of mitigation testing depends critically on test turnover time (time until test result), the detection threshold of tests and mitigation testing frequencies. Under realistic conditions and in absence of vaccinations, we find that mitigation testing of employees only might be sufficient to control outbreaks if tests have low turnover times and detection thresholds. If vaccines that are 60% effective against high viral load and transmission are available, control is achieved if 80% or more of the residents are vaccinated, even without mitigation testing and if residents are allowed to have visitors. Since these results strongly depend on vaccine efficacy against infection, retention of testing infrastructures, regular testing and sequencing of virus genomes is advised to enable early identification of new variants of concern.     

Small Extracellular Vesicles Derived from Human Chorionic MSCs as Modern Perspective towards Cell-Free Therapy

Mesenchymal stem cells (MSCs) are of great interest to scientists due to their application in cell therapy of many diseases, as well as regenerative medicine and tissue engineering. Recently, there has been growing evidence surrounding the research based on extracellular vesicles (EVs), especially small EVs (sEVs)/exosomes derived from MSCs. EVs/exosomes can be secreted by almost all cell types and various types of EVs show multiple functions. In addition, MSCs-derived exosomes have similar characteristics and biological activities to MSCs and their therapeutic applications are considered as a safe strategy in cell-free therapy. The aim of this study was the characterization of MSCs isolated from the chorion (CHo-MSCs) of human full-term placenta, as well as the isolation and analysis of small EVs obtained from these cells. Accordingly, in this study, the ability of small EVs’ uptake is indicated by synovial fibroblasts, osteoblasts and periosteum-derived MSCs. Improvement in the understanding of the structure, characteristics, mechanism of action and potential application of MSCs-derived small EVs can provide new insight into improved therapeutic strategies.     

Poly(2,6-dimethyl-1,4-phenylene ether) (PPO®) capping and its significance in the preparation of PPO®/epoxy laminate

The thermal expansion property at 288°C of poly(2,6-dimethyl-1,4-phenylene ether) (PPO®)/epoxy laminate was found to be affected by the PPO/epoxy copolymer content in the laminate. Capping of redistributed PPO with epoxide-containing reagents such as Araldite® EPN 1138 and an “upstaged” resin was readily accomplished with tetraethylammonium hydroxide or N, N-dimethylaminopyridine as the catalyst during the varnish preparation step. The resulting PPO/epoxy laminate maintained the nonlofting property despite the presence of phenolic hardener (curing accelerator) and antimony pentoxide (flame retardant) in the formulation. © 1996 John Wiley & Sons, Inc.