Pre-hospital management and outcome of acute poisonings by ambulances in Yekaterinburg, Russia.

INTRODUCTION: Large, prospective pre-hospital studies of acute poisonings are scarce. We present the epidemiology of the pre-hospital poisonings, the treatment given, the complications of the poisoning itself and the treatment, predictors for hospitalization, and the safety of the present approach in a large industrial Russian city. METHODS: Data were collected from March 2009 to March 2010. All adult (≥ 16 years) acute poisonings in the city of Yekaterinburg, Russia were included. The prospective cohort inclusion of data included age, gender, simple clinical features (including consciousness, respiratory status, circulatory status, convulsions, etc.), main toxic agent, reason why poisoning was suspected, treatment given, and outcome. Multivariate logistic regression analysis was used to identify the factors associated with hospitalization of the patients. RESULTS: In total, 1795/2536 patients (71%) were brought to hospitals, 736/2536 (29%) were discharged by the ambulance, and 5/2536 (0.2%) died on scene. The most frequent main agents were opioids (25%), ethanol (9%), benzodiazepines (8%), corrosive substances (7%), carbon monoxide (5%), and neuroleptics (5%). Pre-hospital treatment was given to 73% of patients; 3% were intubated, and antidotes were given in 27% (naloxone 24%, atropine 2%, and flumazenil 0.2%). Gastric lavage was performed in 34%, but only 20% within the first hour after ingestion; 49% had a Glasgow Coma Scale (GCS)< 15, but only 6% of them were intubated in the ambulance. Activated charcoal was given to two patients, both with a GCS = 15. A suicidal behavior was the strongest predictor for hospitalization. CONCLUSION: This study reveals current practice differing from the common treatment practice in most places, especially concerning the use of gastric lavage. Whether the current practice led to an increased morbidity and mortality is uncertain, but it justifies the need for thorough evaluation of clinical practice. These findings highlight the importance of studies like the present to improve diagnostics, triage, and treatment in acute poisonings.

DNA inhibits dsRNA-induced secretion of pro-inflammatory cytokines by gingival fibroblasts.

Nucleic acids interacting with pattern-recognizing receptors (PRRs), such as Toll-like-(TLRs), RIG-I-like receptors (RLRs) and dsDNA-receptors activate innate immune response in non-professional immune cells and thus the production of pro-inflammatory cytokines. Along with bacterial and viral nucleic acids, endogenous cell-free and cell-surface-bound extracellular DNA (exDNA and csbDNA) could interact with PRRs and possess immunomodulating activity. To elucidate if exDNA influence innate immunity a comparative study of exDNA, genomic and plasmid DNA on interleukin production in gingival fibroblasts (GF) has been done. All DNA tested have no effect on IL secretion in a broad concentration range (10 ng/ml-1 µg/ml). Simultaneous treatment of cells with DNA and dsRNA analog poly(I:C) leads to inhibition of poly(I:C)-activated secretion of IL-6 and IL-8. Cell-surface-bound DNA possesses two times stronger inhibiting effect as compared to genomic DNA indicating the enrichment of csbDNA in sequences providing such activity. Effects of several recently found specific DNA sequences tightly bound with cell surface have been tested. Joint stimulation of GF with poly(I:C) and deoxyribooligonucleotides (ODN), containing such sequences, demonstrates that both ssODN and dsODN possess sequence-dependent inhibiting effect. Inhibition of IL production after colipofection of ODN and poly(I:C) into cells indicates the involvement of RLRs or other cytoplasmic factors in the effect. The data obtained indicate that endogenous DNA might be involved in regulation of antiviral immune response and sequence-specific ODNs are potential inhibitors of the inflammation induced by viral infection.

Ku protein as the main cellular target of cell-surface-bound circulating DNA.

OBJECTIVE: An immunomodulatory activity of circulating DNA (cirDNA) is implemented via the interactions of cirDNA with the targets exposed on the cell membrane and/or intracellular targets. The goal of this work was to identify the cellular targets of immunoinhibiting cell-surface-bound cirDNA (csbDNA) using its oligodeoxyribonucleotide (ODN) analogs containing the nucleotide motifs frequently found in csbDNA and displaying the same effects. MATERIALS AND METHODS: The binding of [(32)P]-labeled single- and double-stranded ODNs (ss- and ds-ODNs) with membrane-cytosolic (MC) extracts and living human umbilical vein endothelial cells (HUVEC) was studied by electromobility shift assay (EMSA). Complexes of biotinylated ODNs with target proteins were affinity isolated using streptavidin Sepharose with subsequent SDS-PAGE and identified by MALDI-TOF mass spectrometry. RESULTS AND CONCLUSIONS: Both ss- and ds-ODNs form strong ODN-protein complexes with similar electrophoretic mobilities after incubation with the MC extracts of HUVEC either when added extracellularly or lipofected into cells. The ODN-binding proteins were identified as the DNA-binding components of DNA-dependent protein kinase (DNA-PK), namely, Ku70 and Ku80 proteins. Diverse cellular localizations and functions of the Ku proteins demand further clarification of Ku70/80 role as a mediator of the csbDNA immunoinhibiting effects.