The study was conducted to select the best promising keratinolytic bacterial strain. A good keratinase positive bacterium isolated from the soil samples of Hazaribagh tannery industrial zone, Dhaka was identified as Arthrobacter genus depending on the conventional techniques and confirmed as Arthrobacter sp. by sequencing 16S rRNA gene. The medium components and culture conditions were optimized to enhance keratinase production through shake flask culture. Keratin and feather powder (10 g/l or 1%) were good substrates for the highest keratinase production along with yeast extract (0.2 g/l or 0.02%) as an organic nitrogen source and potassium nitrate (1 g or 0.1%) as an inorganic nitrogen source. Maximum yield of keratinase was found after 24 h of incubation at 37 °C with an initial pH of 7.0 and inoculums volume 5% under 150 rpm when keratin, yeast extract and potassium nitrate were used as nutrient sources. Keratinase production was more than 5.0-fold increased when all optimized parameters were applied simultaneously. The optimum reaction temperature and pH were determined to be 40 °C and 8.0 respectively for crude keratinase activity. Therefore, Arthrobacter sp. NFH5 might be used for large scale production of keratinase for industrial purposes in less time.Electronic supplementary materialThe online version of this article (doi:10.1186/s13568-017-0462-6) contains supplementary material, which is available to authorized users.

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Alternative bone regeneration strategies that do not rely on harvested tissue or exogenous growth factors are needed. One of the major challenges in tissue reconstruction is recreating the bone tissue microenvironment using the appropriate combination of cells, scaffold, and stimulation to direct differentiation. This study presents a bone regeneration formulation that involves the use of human adipose‐derived mesenchymal stem cells (hASCs) and a three‐dimensional (3D) hydrogel scaffold based on self‐assembled RADA16 peptides containing superparamagnetic iron oxide nanoparticles (NPs). Although superparamagnetic NPs could be used as stimulus to manipulate the cell proliferation and differentiation, in this paper their use is explored for assisting osteogenic differentiation of hASCs in conjunction with direct stimulation by extremely low‐frequency pulsed electromagnetic fields (pEMFs). Cellular morphology, proliferation, and viability, as well as alkaline phosphatase activity, calcium deposition, and osteogenic capacity were monitored for cells cultured up to 21 days in the 3D construct. The results show that the pEMFs and NPs do not have any negative effect on cell viability, but instead distinctly induced early differentiation of hASCs to an osteoblastic phenotype, when compared with cells without biophysical stimulation. This effect is attributed to synergy between the pEMFs and NPs, which may have stimulated mechanotransduction pathways, which, in turn activated biochemical signals between cells to differentiate or proliferate. This approach may offer a safe and effective option for the treatment of non‐union bone fractures. Bioelectromagnetics. © 2020 The Authors. Bioelectromagnetics published by Wiley Periodicals, Inc.

PurposeThe paper aims to investigate the most influential social media information sources to trust in healthcare facilities. The article shows a valuable point of reference for understanding how social media becomes the casting of social capital.Design/methodology/approachThis paper has taken 660 responses from the people who used social media for healthcare information in the mid of 2020 during the pandemic. The people were approached through different social media groups. The paper conducted structural equation modelling (SEM). The result has shown that with the instigating power of social capital where people put trust in social media information during pandemics.FindingsThe findings demonstrated that personal sources, government organisations and healthcare professionals are the most influential sources of social media. In order to effectively ensure the encompassing provision of COVID-19 health services, this article argues that social capital considerations establish trust between healthcare facilities seeking community to healthcare information providers.Research limitations/implicationsThis research has signified that social cohesion and concern for community welfare instigated people to engage in social media communication. The inherent social capital belongings influence people to trust the sources of health information from selected sources that appear on social media.Practical implicationsHealthcare policymakers may utilise this intense feeling of belongingness and cohesion of social capital and use social media platforms to spread health-related information.Originality/valueThe study shows social capital has the strength to entice people into healthcare-seeking behaviour. In this era, social capital is reformulated to digital social capital through social media and strongly affects people's trust.

Much of the current understanding on molecular and cellular events of adipose developmental biology comes from monolayer cell culture models using preadipocyte cell lines, although in vivo adipose tissue consists of a much more complex three-dimensional microenvironment of diverse cell types, extracellular network, and tissue-specific morphological and functional features. Added to this fact, the preadipocytes, on which the adipogenesis mechanisms are mostly explored, possess some serious limitations (e.g., time of initial subculture and adipogenic differentiation time), which, perhaps, can efficiently be replaced with progenitor cells such as adipose tissue-derived stem cells (ASCs). With the objective of developing a better in vitro model for adipose developmental biology, this project involves gene expression profiling of human ASCs (hASCs) during their differentiation to adipocytes in a 2D versus 3D culture model. This transcriptional-level analysis revealed that gene expression patterns of adipogenesis-induced hASCs in a 3D selfassembled polypeptide hydrogel are relatively different from the 2D monolayered cells on plastic hard substrate.Moreover, analysis of adipogenic lineage progression 9 days after adipogenic induction shows earlier differentiation of hASCs in 2D over their 3D counterparts. However, differentiation in 2D shows some unexpected behavior in terms of gene expression, which does not seem to be related to adipogenic lineage specification. Since hASCs are already being used in clinical trials due to their therapeutic potential, it is important to have a clear understanding of the molecular mechanisms in an in vivo model microenvironment like the one presented here.