Evaluation of Different Polymeric Organic Materials for Creating Conditions That Favor Reductive Processes in Groundwater

The ability of three different polymeric organic materials (POMs) to create redox conditions favorable for reductive processes such as dechlorination was evaluated over a period of 70 days. Corn crop residue, unrefined chitin, and wood shavings were mixed with sand, packed into columns, and flushed with fresh groundwater once per day. Extracted groundwater was evaluated for pH, hydrogen, methane, volatile fatty acids (VFAs), alcohols, dissolved organic carbon (DOC), and chemical oxygen demand (COD). The pH measured for all POMs was between 5 and 8.5, with values after 30 days generally between 6 and 8. Hydrogen and methane concentrations indicated that all columns remained anaerobic during the entire experiment. Acetate was the dominant VFA in all columns, although propionate, butyrate, isobutyrate, and isovalerate were detected at much lower concentrations. Also, acetate concentrations were greater at all times in columns containing unrefined chitin (4 to 43 mM) than in those containing either corn crop residue (1 to 7 mM) or wood shavings (0 to 3 mM). Total electron donating capacities for dechlorination (expressed as total chloride removal capacities) were estimated from total COD and hydrogen concentrations. This capacity was greater in the column containing unrefined chitin than in those containing either corn crop residue or wood shavings. Overall the electron donating capacities remaining after 70 days were 40%, 11%, and 44% of the initial values for the corn crop residue, the unrefined chitin, and the wood shavings, respectively. The results indicate that over a 70-day period, anaerobic and nutrient-rich conditions were sustained for all POMs, but that the amount of electron donor available for reductive terminal electron accepting processes varies between POMs and is greatest for unrefined chitin.     

Use and Utility of Hemostatic Screening in Adults Undergoing Elective,Non-Cardiac Surgery

Introduction

One view of value in medicine is outcome relative to cost of care provided. With respect to operative care, increased attention has been placed on evaluation and optimization of patients prior to undergoing an elective surgery. We examined more than 2 million patients having elective, non-cardiac surgery to assess the incidence and utility of pre-operative hemostatic screening, compared with a composite of history variables that may indicate a propensity for bleeding, to assess several important outcomes of surgery.

Materials & Methods

We queried the NSQIP database to identify 2,020,533 patients and compared hemostatic tests (PT, aPTT, platelet count) and history covariables indicative of potential for abnormal hemostasis. We compared outcomes across predictor values; used Person’s chi-square tests to compare differences, and logistic regression to model outcomes.

Results

Approximately 36% of patients had all three tests pre-operatively while 16% had none of them; 11.2% had a history predictive of potential abnormal bleeding. Outcomes of interest across the cohort included death in 0.7%, unplanned return to the operating room or re-admission within 30 days in 3.8% and 6.2% of patients; 5.3% received a transfusion during or after surgery. Sub-analyses in each of the nine surgical specialties’ most common procedures yielded similar results.

Conclusion

The limited predictive value of each hemostatic screening test, as well as excess costs associated with them, across a broad spectrum of elective surgeries, suggests that limiting pre-operative testing to a more select group of patients may be reasonable, equally efficacious, efficient, and cost-effective.     

Evidence of mesenchymal stromal cell adaptation to local microenvironment following subcutaneous transplantation

Subcutaneous transplantation of mesenchymal stromal cells (MSC) emerged as an alternative to intravenous administration because it avoids the pulmonary embolism and prolongs post‐transplantation lifetime. The goal of this study was to investigate the mechanisms by which these cells could affect remote organs. To this aim, murine bone marrow–derived MSC were subcutaneously transplanted in different anatomical regions and the survival and behaviour have been followed. The results showed that upon subcutaneous transplantation in mice, MSC formed multicellular aggregates and did not migrate significantly from the site of injection. Our data suggest an important role of hypoxia‐inducible signalling pathways in stimulating local angiogenesis and the ensuing modulation of the kinetics of circulating cytokines with putative protective effects at distant sites. These data expand the current understanding of cell behaviour after subcutaneous transplantation and contribute to the development of a non‐invasive cell‐based therapy for distant organ protection.     

New variants in Spanish Niemann–Pick type c disease patients

Molecular Biology Reports - Niemann–Pick type C (NPC) disease is a rare inherited disease, with progressive neurodegeneration as the main symptom. It is a lysosomal storage disorder caused by...     

Poor antibody validation is a challenge in biomedical research: a case study for detection of c-FLIP

Successful translation of findings derived from preclinical studies into effective therapies is critical in biomedical research. Lack of robustness and reproducibility of the preclinical data, due to insufficient number of repeats, inadequate cell-based and mouse models contribute to the poor success rate. Antibodies are widely used in preclinical research, notably to determine the expression of potential therapeutic targets in tissues of interest, including tumors, but also to identify disease and/or treatment response biomarkers. We sought to determine whether the current antibody characterization standards in preclinical research are sufficient to ensure reliability of the data found in peer-reviewed publications. To address this issue, we used detection of the protein c-FLIP, a major factor of resistance to apoptosis, as a proof of concept. Accurate detection of endogenous c-FLIP levels in the preclinical settings is imperative since it is considered as a potential theranostic biomarker. Several sources of c-FLIP antibodies validated by their manufacturer and recommended for western blotting were therefore rigorously tested. We found a wide divergence in immune recognition properties. While these antibodies have been used in many publications, our results show that several of them failed to detect endogenous c-FLIP protein by Western blotting. Our results suggest that antibody validation standards are inadequate, and that systematic use of genetic knockdowns and/or knockouts to establish proof of specificity is critical, even for antibodies previously used in the scientific literature. Because antibodies are fundamental tools in both preclinical and clinical research, ensuring their specificity is crucial.     

Interorgan amino acid interchange in propionic acidemia: the missing key to understanding its physiopathology

Amino Acids - Propionic acidemia is an inborn error of metabolism caused by a deficiency in the mitochondrial enzyme propionyl-CoA carboxylase that converts the propionyl CoA to methyl malonyl CoA....