The relationship between the cholinergic mechanism of toxicity and oxidative stress in rats during subacute diazinon poisoning.

Diazinon is an organophosphate pesticide (OP) that has significant potential for accidental and intentional poisoning of wildlife, domestic animals and humans. The aim of the study is to investigate the correlation between cholinesterase activity and oxidative stress parameters in liver and diaphragm by continuous monitoring as a function of time during prolonged use of diazinon. Wistar rats were treated orally with diazinon (55 mg/kg/day): 7, 14, 21 and 28 days. At the end of each period, blood, liver and diaphragm were collected to examine cholinesterase activity and enzymatic/non-enzymatic oxidative stress parameters: superoxide dismutase 1 (SOD1), catalase (CAT), thiobarbituric acid substances (TBARS), protein carbonyl groups. In all four time periods, there was a significant change in acetylcholinesterase (AChE) in erythrocytes and butyrylcholinesterase (BuChE) in blood plasma, CAT in liver and diaphragm and SOD1 in diaphragm. Parameters significantly altered during the cholinergic crisis included: cholinesterases and TBARS in liver and diaphragm and partially SOD1 in liver. Protein carbonyl groups in liver and diaphragm were significantly altered outside the cholinergic crisis. In the liver, there was a very strong negative correlation between BuChE and TBARS in all four time periods and BuChE and CAT on day 7. In the diaphragm, a very strong negative correlation was found between AChE and TBARS at days 7 and 14, and a very strong positive correlation between AChE and SOD1 at days 14, 21 and 28. A better understanding of the relationship between cholinergic overstimulation and oxidative stress may help to better assess health status in prolonged OPs intoxication.

MTT based L-aminoacid oxidase activity test for determination of antivenom potency against Vipera ammodytes envenomation.

The MTT assay is routinely used to detect the activity of living cells. While working with Vipera ammodytes venom we detected the reduction of MTT without the presence of cells, in a concentration-dependent manner. By combining non-reducing PAGE, L-amino acid oxidase (LAAO) assays, and standard MTT assays, we established and confirmed that venom MTT reduction is catalyzed by only one enzyme, the LAAO. Even though it was previously known that the dimeric and tetrameric forms of LAAO are active, we conclude that the enzyme is also active in the monomeric form. Our results have led to the definition of a new MTT assay in a microtiter plate for in vitro testing of svLAAO activity i.e. from the venom of the V. ammodytes snake. Potentially, this method can be used for testing hemorrhagic venoms of other snakes as well as the LAAO neutralization capability of appropriate antivenoms.

Recovery of brain cholinesterases and effect on parameters of oxidative stres and apoptosis in quails (Coturnix japonica) after chlorpyrifos and vitamin B1 administration.

Chlorpyrifos is a extensively used organophosphate pesticide (OP). In this study, we closely looked into neurotoxicity of CPF and effect of vitamin B1, by checking the levels of cholinesterases, determining the activity of parameters of oxidative stress, inflammation and also level of apoptotic regulator. The study was performed on a total of 80 male Japanese quails (Coturnix japonica), (two control and 6 experimental groups, n = 10). Three group of quails were given by gavage chlorpyrifos (CPF) for 7 consecutive days at doses of 1.50 mg/kg b.w., 3.00 mg/kg b.w., and 6.00 mg/kg b.w. Another three groups were treated with 10 mg/kg b.w. of vitamin B1 i.m. 30 min after CPF application (in above mentioned doses). Our study have proved that all doses of CPF significantly inhibited cholinesterases in brain, while vitamin B1 reactivated them. CPF has led to an increase in the concentration of malondialdehyde (MDA), and activity of catalase (CAT), superoxide dismutase (SOD), glutathione-S-transferase (GST), while tiamin changed the activity of antioxidant enzymes: CAT, SOD, GST. CPF stimulated apoptosis by decreasing B-cell lymphoma (Bcl-2) in brain, while application of vitamin B1 caused an increase of this parameter. CPF amplified inflammatory effect by elevating levels of inducible nitric oxide synthase (iNOS), and cyclooxygenase (COX-2). Thiamine proved its anti-inflammatory property by decreasing the expression of iNOS and interleukin-1(IL-1) and interleukin-6(IL-6). This study is highly pertinent because there is little defense currently available to humans and animals to prevent toxic effects of pesticides.

Novel coronavirus-related acute respiratory distress syndrome in a patient with twin pregnancy: A case report.

We present the case of a 39-year-old woman, G1P0, who had conceived twins via in-vitro fertilization, who presented at 27 weeks of gestation with nasal congestion and dry cough for 7 days. On presentation, her physical examination was benign, except for sinus tachycardia, and she was oxygenating adequately on room air. Laboratory studies were unremarkable, except a PCR test positive for SARS-COV2, and a CT scan of her chest showed bilateral multi-focal ground-glass opacities. A fetal non-stress test was reassuring. She was treated with intravenous fluids, ceftriaxone, azithromycin, and hydroxychloroquine. During her hospital stay, she developed progressively worsening respiratory failure, initially requiring non-invasive ventilation, and subsequently progressed to acute respiratory distress syndrome requiring mechanical ventilation. She then suffered from sudden hypoxemia and hemodynamic collapse, on maximal ventilatory support, prompting an emergency cesarean section at bedside. This led to rapid stabilization of hemodynamic parameters, and of her overall respiratory status. Both the twins were born prematurely, and one of them tested positive for SARS-COV2.

Nitroso-Oxidative Stress, Acute Phase Response, and Cytogenetic Damage in Wistar Rats Treated with Adrenaline.

This study is aimed at analysing biochemical and genetic endpoints of toxic effects after administration of adrenaline. For this purpose, the study was carried out on Wistar rats and three doses of adrenaline were used: 0.75 mg/kg, 1.5 mg/kg, and 3 mg/kg body weight. To achieve these aims, we investigated the effects of adrenaline on catalase (CAT), Cu, Zn-superoxide dismutase (SOD), malondialdehyde (MDA), nitrite (NO2-), carbonyl groups (PCC), and nitrotyrosine (3-NT). Total activity of lactate dehydrogenase (LDH), its relative distribution (LDH1-LDH5) activity, level of acute phase proteins (APPs), and genotoxic effect were also evaluated. The obtained results revealed that all doses of adrenaline induced a significant rise in CAT activity, MDA level, PCC, NO2 -, and 3-NT and a significant decrease in SOD activity compared to control. Adrenaline exerted an increase in total activity of LDH, LDH1, and LDH2 isoenzymes. Further study showed that adrenaline significantly decreased serum albumin level and albumin-globulin ratio, while the level of APPs (α 1-acid glycoprotein and haptoglobulin) is increased. The micronucleus test revealed a genotoxic effect of adrenaline at higher concentrations (1.5 mg/kg and 3 mg/kg body weight) compared to untreated rats. It can be concluded that adrenaline exerts oxidative and nitrative stress in rats, increased damage to lipids and proteins, and damage of cardiomyocytes and cytogenetic damage. Obtained results may contribute to better understanding of the toxicity of adrenaline with aims to preventing its harmful effects.

Downregulation of nicotinic and muscarinic receptor function in rats after subchronic exposure to diazinon.

Diazinon (DZN) is an organophosphate insecticide which exerts its effect through the inhibition of acetylcholinesterase enzyme (AChE). In this work, we studied the development of tolerance to subchronic p.o. administration of DZN in rats, under both in vivo and in vitro conditions. A group of 20 rats (2 groups, n = 10) was administered p.o. the 1/10 of established LD50 DZN (namely 55.87 mg/kg bw) for 28 days. On the 14th and 28th day of study with isolated diaphragm and ileum, we examined the downregulation of nicotinic and muscarinic receptor function through Electrical Field Stimulation (EFS). Maximum contractility of the diaphragm was recorded on the 14th day of the study (25% higher compared to the non-treated rats), while on the 28th day the contractions almost did not differ from the values found in non-treated rats. EFS of isolated ileum on the 14th day of study caused significantly higher contractions compared to the non-treated rats, but after 28 days, ileum contractions decreased approximately to the level of contractions in non-treated rats. On the 14th study day, we also recorded increased amplitude of spontaneous ileum contractions, compared to non-treated rats. The application of increasing ACh concentrations caused dose-dependent ileum contractions, without statistically significant differences of median effective concentration (EC50) values in non-treated and treated rats. Tolerance to subchronic DZN administration develops due to various adaptation mechanisms, including the most important one-downregulation of nicotinic and muscarinic receptor function.

We thought we would be perfect: medication errors before and after the initiation of Computerized Physician Order Entry.

BACKGROUND: Because the Institute of Medicine demanded health care improvement, electronic medical records have been implemented with the hopes of eliminating iatrogenic injury caused by avoidable mistakes. Electronic orders and electronic medical records survived its initial slow adoption and have since had a myriad of identifiable flaws as it becomes incorporated nationally. MATERIALS AND METHODS: This retrospective study at a university teaching hospital analyzed all medication order errors (OEs) for the 26 wk of paper-order entries before computer physician order entry (CPOE) and 26 weeks after CPOE was initiated. All OEs were included and documented by month as well as severity using standard taxonomy. RESULTS: Results indicated that CPOE yielded a significant increase in overall medication OE with five of six severity categories remaining the same or increasing in OE. Severity categories A and E saw a significant increase once CPOE began (P < 0.01). Pre-CPOE OEs were 1741, whereas Post-CPOE OEs were 2226, showing an increase in overall medication errors (P < 0.01). After CPOE began, the cumulative successive errors recorded were 112, 290, 267, 307, 412, 399, and 439 with an R(2) value of 0.849 and a P value of 0.003 in the analysis of variance to test regression relation. CONCLUSIONS: As CPOE adapts for its real-world applications, it may eventually prove useful in reducing errors; however, perfection and error free order entry will not be achieved unless objective data analysis guides its evolution.

Ivermectin effects on motor coordination and contractions of isolated rat diaphragm.

Ivermectin, the antiparasitic drug from the macrocyclic lactones class raises attention due to its high efficiency against nematodes and arthropods and very specific toxic and side effects that it may produce in host. Dominant clinical symptoms of adverse effects and toxicity of ivermectin in animals are tremor, ataxia, CNS depression and coma which often results in mortality. In our study increasing intravenous doses of ivermectin, (6 or more times higher than therapeutic dose: 1.25, 2.5, 3.75, 5.0, 6.25 and 7.5 mg/kg), caused dose-dependent disturbance of motor coordination in treated rats. The median effective dose (ED50) that was able to impair the rota-rod performance in rats treated 3 min before testing was 2.52 mg/kg. This effect weakens over time, while in the rats treated 60 min before the rota-rod test, ED50 of ivermectin was 4.21 mg/kg. Whereas, all tested doses of ivermectin did not cause any other clinical symptoms of toxicity. Ivermectin has no effect on the contractions of isolated diaphragm caused by the EFS, which effectively blocked mecamylamine (100 µM) and pancuronium (1 and 2 µM). Effect on motor coordination is the first detectable clinical symptom of ivermectin toxicity and apparently is a result of its central effects.