From unstructured accident reports to a hybrid decision support system for occupational risk management: The consensus converging approach.

INTRODUCTION: Workplace accidents in the petroleum industry can cause catastrophic damage to people, property, and the environment. Earlier studies in this domain indicate that the majority of the accident report information is available in unstructured text format. Conventional techniques for the analysis of accident data are time-consuming and heavily dependent on experts' subject knowledge, experience, and judgment. There is a need to develop a machine learning-based decision support system to analyze the vast amounts of unstructured text data that are frequently overlooked due to a lack of appropriate methodology. METHOD: To address this gap in the literature, we propose a hybrid methodology that uses improved text-mining techniques combined with an un-bias group decision-making framework to combine the output of objective weights (based on text mining) and subjective weights (based on expert opinion) of risk factors to prioritize them. Based on the contextual word embedding models and term frequencies, we extracted five important clusters of risk factors comprising more than 32 risk sub-factors. A heterogeneous group of experts and employees in the petroleum industry were contacted to obtain their opinions on the extracted risk factors, and the best-worst method was used to convert their opinions to weights. CONCLUSIONS AND PRACTICAL APPLICATIONS: The applicability of our proposed framework was tested on the data compiled from the accident data released by the petroleum industries in India. Our framework can be extended to accident data from any industry, to reduce analysis time and improve the accuracy in classifying and prioritizing risk factors.

Autologous lung-derived mesenchymal stem cell transplantation in experimental emphysema.

Autologous lung-derived mesenchymal stem cells (LMSCs) were transplanted endoscopically into sheep with experimental emphysema to assess their capacity to regenerate functional tissue. LMSC lines were derived from transbronchial biopsies, cloned at passage 2, expanded in culture, and labeled. A delivery scaffold containing 1% fibrinogen, 20 µg/ml of fibronectin, and 20 µg/ml of poly-L-lysine was used to promote cell attachment and spreading. Treatment animals received scaffold containing 5-10 × 10(6) cells/site; control animals received scaffold alone. Phenotypic markers, differentiation capacity, extracellular matrix protein expression, and paracrine function of LMSCs were characterized in vitro. Responses to LMSC transplantation in vivo were assessed in terms of clinical toxicity, lung physiology, change in tissue mass (measured by CT scanning) and perfusion (measured by scintigraphy scanning), and tissue histology. At 4-week follow-up, transplants were well tolerated and associated with increased tissue mass and lung perfusion compared to control treatment. Histology confirmed cell retention, increased cellularity, and increased extracellular matrix content following LMSC treatment. Labeled cells were distributed in the alveolar septum and peribronchiolar interstitium. Some label was also present within phagocytes, indicating that a fraction of autologous LMSCs do not survive transplantation. These results suggest that endobronchial delivery of autologous LMSCs has potential therapeutic utility for regenerating functional lung in emphysema.

Lung-derived mesenchymal stromal cell post-transplantation survival, persistence, paracrine expression, and repair of elastase-injured lung.

While multipotent mesenchymal stromal cells have been recently isolated from adult lung (L-MSCs), there is very limited data on their biological properties and therapeutic potential in vivo. How L-MSCs compare with bone marrow-derived MSCs (BM-MSCs) is also unclear. In this study, we characterized L-MSC phenotype, clonogenicity, and differentiation potential, and compared L-MSCs to BM-MSCs in vivo survival, retention, paracrine gene expression, and repair or elastase injury after transplantation. L-MSCs were highly clonogenic, frequently expressed aldehyde dehydrogenase activity, and differentiated into osteocytes, chondrocytes, adipocytes, myofibroblasts, and smooth muscle cells. After intravenous injection (2 h), L-MSCs showed greater survival than BM-MSCs; similarly, L-MSCs were significantly more resistant than BM-MSCs to anchorage independent culture (4 h) in vitro. Long after transplantation (4 or 32 days), a significantly higher number of CD45(neg) L-MSCs were retained than BM-MSCs. By flow cytometry, L-MSCs expressed more intercellular adhesion molecule-1 (ICAM-1), platelet derived growth factor receptor alpha (PDGFRα), and integrin α2 than BM-MSCs; these proteins were found to modulate endothelial adherence, directional migration, and migration across Matrigel in L-MSCs. Further, L-MSCs with low ICAM-1 showed poorer lung retention and higher phagocytosis in vivo. Compared with BM-MSCs, L-MSCs expressed higher levels of several transcripts (e.g., Ccl2, Cxcl2, Cxcl10, IL-6, IL-11, Hgf, and Igf2) in vitro, although gene expression in vivo was increased by L-MSCs and BM-MSCs equivalently. Accordingly, both L-MSCs and BM-MSCs reduced elastase injury to the same extent. This study demonstrates that tissue-specific L-MSCs possess mechanisms that enhance their lung retention after intravenous transplantation, and produce substantial healing of elastase injury comparable to BM-MSCs.

Design and testing of biological scaffolds for delivering reparative cells to target sites in the lung.

This study summarizes the development and testing of a scaffold to promote engraftment of cells in the distal lung. A fibrinogen-fibronectin-vitronectin hydrogel (FFVH) was developed and optimized with respect to its mechanical and biological properties for this application. In vitro, FFVH scaffolds promoted attachment, histiotypic growth and expression of basement membrane proteins by primary ovine lung mesenchymal cells derived from lung biopsies. In vivo testing was then performed to assess the ability of FFVHs to promote cell engraftment in the sheep lung. Treatment with autologous cells delivered using FFVH was clinically well tolerated. Cells labelled with a fluorescent dye (PKH-26) were detected at treatment sites after 1 month. Tissue mass (assessed by CT imaging) and lung perfusion (assessed by nuclear scintigraphy) were increased at emphysema test sites. Post-treatment histology demonstrated cell proliferation and increased elastin expression without scarring or collapse. No treatment-related pathology was observed at healthy control sites. FFVH scaffolds promote cell attachment, spreading and extracellular matrix expression in vitro and apparent engraftment in vivo, with evidence of trophic effects on the surrounding tissue. Scaffolds of this type may contribute to the development of cell-based therapies for patients with end-stage pulmonary diseases.