Biosynthesis of Bacterial Nanocellulose from Low-Cost Cellulosic Feedstocks: Effect of Microbial Producer.

Biodegradable bacterial nanocellulose (BNC) is a highly in-demand but expensive polymer, and the reduction of its production cost is an important task. The present study aimed to biosynthesize BNC on biologically high-quality hydrolyzate media prepared from miscanthus and oat hulls, and to explore the properties of the resultant BNC depending on the microbial producer used. In this study, three microbial producers were utilized for the biosynthesis of BNC: individual strains Komagataeibacter xylinus B-12429 and Komagataeibacter xylinus B-12431, and symbiotic Medusomyces gisevii Sa-12. The use of symbiotic Medusomyces gisevii Sa-12 was found to have technological benefits: nutrient media require no mineral salts or growth factors, and pasteurization is sufficient for the nutrient medium instead of sterilization. The yield of BNCs produced by the symbiotic culture turned out to be 44-65% higher than that for the individual strains. The physicochemical properties of BNC, such as nanofibril width, degree of polymerization, elastic modulus, Iα allomorph content and crystallinity index, are most notably dependent on the microbial producer type rather than the nutrient medium composition. This is the first study in which we investigated the biosynthesis of BNC on hydrolyzate media prepared from miscanthus and oat hulls under the same conditions but using different microbial producers, and showed that it is advisable to use the symbiotic culture. The choice of a microbial producer is grounded on the yield, production process simplification and properties. The BNC production from technical raw materials would cover considerable demands of BNC for technical purposes without competing with food resources.

Ecotoxicity to Freshwater Organisms and Cytotoxicity of Nanomaterials: Are We Generating Sufficient Data for Their Risk Assessment?

The aim of the present study was to investigate the eco-cytotoxicity of several forms of nanomaterials (NM), such as nano-CuO, nano-TiO2, nano-SiO2 and nano-ZnO, on different aquatic species (Raphidocelis subcapitata, Daphnia magna and Lemna minor) following standard protocols and on human cell lines (Caco-2, SV-80, HepG2 and HaCaT). Predicted no-effect concentrations (PNEC) or hazard concentrations for 5% of the species (HC5) were also estimated based on the compilation of data available in the literature. Most of the NM agglomerated strongly in the selected culture media. For the ecotoxicity assays, nano-CuO and nano-ZnO even in particle agglomeration state were the most toxic NM to the freshwater organisms compared to nano-TiO2 and nano-SiO2. Nano-ZnO was the most toxic NM to R. subcapitata and D. magna, while nano-CuO was found to be very toxic to L. minor. Nano-CuO was very toxic to Caco-2 and HepG2 cells, particularly at the highest tested concentrations, while the other NM showed no toxicity to the different cell lines. The HC5 and PNEC values are still highly protective, due to data limitations. However, the present study provides consistent evidence of the potential risks of both nano-CuO and nano-ZnO against aquatic organisms and also their effects on public health.

The Yekaterinburg headache initiative: an interventional project, within the Global Campaign against Headache, to reduce the burden of headache in Russia.

BACKGROUND: As major causes of global public ill-health and disability, headache disorders are paradoxically ignored in health policy and in planning, resourcing and implementing health services. This is true worldwide. Russia, where the prevalence of headache disorders and levels of attributed disability are well in excess of the global and European averages, is no exception, while arcane diagnoses and treatment preferences are an aggravating factor. Urgent remedial action, with political support, is called for. METHODS: Yekaterinburg, in Sverdlovsk Oblast, is the chosen centre for a demonstrational interventional project in Russia, undertaken within the Global Campaign against Headache. The initiative proposes three actions: 1) raise awareness of need for improvement; 2) design and implement a three-tier model (from primary care to a single highly specialized centre with academic affiliation) for efficient and equitable delivery of headache-related health care; 3) develop a range of educational initiatives aimed at primary-care physicians, non-specialist neurologists, pharmacists and the general public to support the second action. RESULTS AND CONCLUSION: We set these proposals in a context of a health-care needs assessment, and as a model for all Russia. We present and discuss early progress of the initiative, justify the investment of resources required for implementation and call for the political support that full implementation requires. The more that the Yekaterinburg headache initiative can achieve, the more likely it is that this support will be forthcoming.

Quick assessment of cytotoxins effect on Daphnia magna using in vivo fluorescence microscopy.

A novel approach to contaminant toxicity screening is proposed. The use of fluorescent microscopy with fluorescent dyes allows for assessing intoxication of Daphnia magna tissues, at various stages of exposure, to contaminants present in water. As shown, D. magna may not only be used as a test species in toxicity tests based on its lethality, but due to its translucency and application of fluorescent probes, separate steps of its intoxication and dying can be visualized. Using a variety of fluorescent probes, the present study also contributes to a better understanding of the toxicity mechanisms.

Equivalence of a single saline nebulised dose of formoterol powder vs three doses of nebulised Albuterol every twenty minutes in acute asthma in children: a suitable cost effective approach for developing nations.

BACKGROUND: An increase in asthma prevalence is reported from developed as well as developing nations, with rising costs from acute asthma and great expenditures to health care systems. Venezuela's Ministry of Health ambulatory facilities care for 80 % or more of a mostly urban and impoverished population of 26 million inhabitants, registering close to a million acute asthma visits per year; a nebulised fixed fenoterol-ipratropium bromide combination (Bero-dual, Boehringer-Ingelheim) in repeated dosing is the standard treatment. OBJECTIVES: to simplify acute asthma care and management in a cost effective manner employing Formoterol Fumarate powder, a long acting beta agonist with immediate bronchodilator effects. METHODOLOGY: Fifty acute asthmatic children (5-12 years old) were randomly assigned (25 patients in each group) to receive either a nebulised single dose (US $1.35) of two 12 microg Formoterol Fumarate capsules (Foradil 12 microg/cap, Novartis Pharma AG, Basel, Switzerland) diluted in 2.5 ml of sterile saline solution; or 3 doses of Albuterol (US $ 6.73) every twenty minutes for one hour (Glaxo Smith Kline Albuterol ampoules, 2.5 mg/2.5 ml, at a dose of 0.15 mg/kg/dose, maximum dose 2.5 mg). Symptoms score, oxygen saturation and lung function testing were recorded before and one hour after commencing treatments. RESULTS: Both groups improved significantly on all parameters, except for FEV(1) in the Albuterol group. CONCLUSIONS: Single dose nebulised Formoterol Fumarate (dry powder) in sterile saline solution, as depicted in this trial, is equivalent to three doses of Albuterol every twenty minutes for one hour in acute asthma in children, simplifying acute care management and at one fifth of medication costs. A pursuit of simpler and more cost effective approaches is found wanting in developing nations with depressed economies and unique cultural and socio-medical contexts; also, in countries where pharmaco-economics orients quality of health policies, novel approaches like this are worth exploring.