Regulating the production and biological function of small extracellular vesicles: current strategies, applications and prospects

Numerous studies have confirmed the great application potentials of small extracellular vesicles (sEVs) in biological medical field, especially in tissue repair and regeneration. However, the production capability of sEVs by noncancerous cells is very limited, while their dosage requirements in disease treatments are usually very high. Meanwhile, as cell aging, the sEV production capability of cells decreases and the biological function of sEVs changes accordingly. In addition, for special applications, sEVs carrying desired bioactive substances should be designed to perform their expected biological function. Therefore, improving the production of sEVs and precisely regulating their biological function are of great significance for promoting the clinical applications of sEVs. In this review, some of the current classic strategies in affecting the cellular behaviors of donor cells and subsequently regulating the production and biological function of their sEVs are summarized, including gene engineering methods, stress-inducing conditions, chemical regulators, physical methods, and biomaterial stimulations. Through applying these strategies, increased yield of sEVs with required biological function can be obtained for disease treatment and tissue repair, such as bone regeneration, wound healing, nerve function recovery and cancer treatment, which could not only reduce the harvest cost of sEV but promote the practical applications of sEVs in clinic. Graphical Abstract

Buyer-assisted lean intervention in supplier firms: a supplier development approach

PurposeThis study aims to investigate how buyer-assisted lean intervention in garment supplier factories affects garment suppliers' productivity and production capability development.Design/methodology/approachEmploying a qualitative research approach and a lean intervention design, a multiple case study method was adopted for this study. Quantitative data on productivity performance and qualitative data on production capability development were collected from a Danish buyer and their four corresponding garment suppliers. Collected data were analysed using standard lean measurement tools and qualitative data analysis techniques.FindingsThis study demonstrates that buyer-assisted lean intervention is a useful strategy for garment suppliers to enhance their productivity and production capability. However, suppliers need to select the right lean tools, ensure seriousness and commitment to lean initiatives, substantial involvement of top management and workers, arrange formal and informal training, provide performance-based financial/non-financial incentives and nurture a learning culture to facilitate suppliers' production capability development.Research limitations/implicationsThis study implemented few lean tools in a single sewing line in four supplier factories for a short intervention duration. Thus, there is a scope for future studies to investigate the impact of the lean intervention on a large scale.Practical implicationsThe findings of this study might bring new insights to the management of buyer and supplier firms concerning how buyers could involve in suppliers' lean intervention initiatives and what suppliers need to ensure to develop production capability.Originality/valueFor the first time, this study engaged a buyer in suppliers' lean intervention initiatives to improve productivity and production capability in the garment industry of a developing country.

Metabolic Current Production by an Oral Biofilm Pathogen Corynebacterium matruchotii

The development of a simple and direct assay for quantifying microbial metabolic activity is important for identifying antibiotic drugs. Current production capabilities of environmental bacteria via the process called extracellular electron transport (EET) from the cell interior to the exterior is well investigated in mineral-reducing bacteria and have been used for various energy and environmental applications. Recently, the capability of human pathogens for producing current has been identified in different human niches, which was suggested to be applicable for drug assessment, because the current production of a few strains correlated with metabolic activity. Herein, we report another strain, a highly abundant pathogen in human oral polymicrobial biofilm, Corynebacterium matruchotii, to have the current production capability associated with its metabolic activity. It showed the current production of 50 nA/cm2 at OD600 of 0.1 with the working electrode poised at +0.4 V vs. a standard hydrogen electrode in a three-electrode system. The addition of antibiotics that suppress the microbial metabolic activity showed a significant current decrease (>90%), establishing that current production reflected the cellular activity in this pathogen. Further, the metabolic fixation of atomically labeled 13C (31.68% ± 2.26%) and 15N (19.69% ± 1.41%) confirmed by high-resolution mass spectrometry indicated that C. matruchotii cells were metabolically active on the electrode surface. The identified electrochemical activity of C. matruchotii shows that this can be a simple and effective test for evaluating the impact of antibacterial compounds, and such a method might be applicable to the polymicrobial oral biofilm on electrode surfaces, given four other oral pathogens have already been shown the current production capability.