Veterinary and human toxicology最新文献

This study compared CYP-mediated activation and toxicity of chlorpyrifos (CPF) in male and female rats, since gender difference in CPF toxicity in rats has been reported. A dose of 50 mg/kg of CPF in corn oil was administered ip to 2 groups of male and female rats while the respective control groups received the vehicle alone. Measurement of cholinesterase activity in brain showed no difference in cholinesterase inhibition between male and female rats 3 h following CPF administration. In contrast, inhibition of plasma cholinesterase was significantly greater in females than males. The activities of microsomal CYP 1A1, 2B1, 2E1 and 3AV 2 determined whether CPF, a suicide substrate of cytochrome P450 enzymes, was metabolized by the liver CYP enzymes. The CYP 1A1 and 2B1 activities were significantly decreased in both male and female rats, with the CYP 1A1 decrease in females markedly greater than that in males. CPF produced a significant inhibition of only CYP 3A1/2 activity, but not CYP 2E1 activity, irrespective of gender effect. These results demonstrated that CYP 1A1, 2B1 and 3A1/2 were differentially involved in the metabolism of CPF to CPF-oxon in both genders and the extent of plasma cholinesterase inhibition was significantly greater in female than male rats.

The Vietnamese centipede (Scolopendra subspinipes) is one of the largest and most aggressive tropical centipedes. It has become a popular pet among arthropod enthusiasts and the general public. Despite their reputation, few well-documented cases of envenomation are reported in the medical literature. A 53-yo man developed severe pain, swelling and erythema of his left hand and forearm after being bitten on the hand by his pet Vietnamese centipede. The neurological and vascular examination of the arm was normal. He was admitted to the hospital, treated with arm elevation, analgesics and parenteral antibiotics. His symptoms gradually resolved and he was discharged after 4 d with no neurological or cosmetic sequelae.

Antimony is a poisonous element with toxic properties that mimic those of arsenic. Numerous reports describe gastrointestinal complications of vomiting, diarrhea and stomatitis associated with antimony exposure. However, antimony toxicity from the use of tartar emetic as a treatment for alcohol abuse has never been described previously. A 19-y-o man with a history of alcohol abuse ingested a 10 mL bottle of "Soluto Vital" (tartar emetic, 50 mg/mL), produced in Guatemala for treatment of alcohol abuse. He presented 60 min after ingestion with severe vomiting, abdominal cramps, diarrhea, weakness and orthostasis. Initial laboratory evaluations were remarkable for creatinine of 2.5 mg/dL, potassium 6.1 mEq/L, and 60% hematocrit. He was given activated charcoal, iv saline and antiemetics. Over the next 48 h his creatinine normalized to 1.1 mg/dL and the hematocrit returned to 53%; urine had an antimony concentration of 1200 mcg/L (normal = < 10 mcg/L). It is important to recognize that foreign alcohol therapies aversive therapy other than disulfiram may be used, the contents of such a foreign product should be identified.

We report the first case from Turkey of a dermonecrotic wound associated with possible Loxosceles spider bite and offer the complete clinical course that resulted in a permanent scar. Emergency physicians in western Turkey should be aware of Loxosceles spider bites as a cause of necrotizing wounds.

Heightened toxicovigilance since the terrorist actions of 9/11 has raised concerns for malicious use of highly toxic botanicals, as the 3 cases reported illustrate.

September 11, 2001 demonstrated dramatic voids in national preparedness, and catalyzed massive efforts to identify and remedy vulnerabilities. Since Part I of this series appeared in August 2002, significant improvements have been achieved especially in bioterrorism and chemical terrorism for first responders and emergency medicine, law enforcement, and public health (surveillance). Such efforts manifested benefits during the SARS outbreaks and monkeypox cases of 2003. Nevertheless, emerging infectious diseases will continue to pose a threat if we do not remain vigilant and continue to invest in training, surveillance, and treatments. As expected, many poison centers and toxicologists have taken leadership roles nationwide. In regions where such leadership existed, preparedness levels are strong and collaborations resulted in the development of valuable response plans and training, including the Advanced Hazardous Life Support (AHLS) and Basic Disaster Life Support (BDLS) courses. Early success notwithstanding, experts suggest that current national preparedness has improved slightly from "1" (9/11) to "3" out of "10". Increasingly it has become evident that the nuclear threat, including radiation terrorism, is significant, against which the US remains inadequately prepared. Arguably the nuclear threat-whether accidental or planned-remains our highest consequence vulnerability, and we must rapidly improve our readiness across disciplines. Special populations including the elderly and children remain marginalized in preparedness protocols. Local vulnerabilities including chemical manufacturing and transportation--not just a risk for terrorism but industrial accidents--continue unabated. Our early success is not an endpoint; much work remains and time is fleeting. This report examines vulnerabilities that must be addressed to enhance preparedness.

Acute ingestion of copper sulfate has been reported to cause gastrointestinal injury, hemolysis, methemoglobinemia, hepatorenal failure, shock; or even death. The toxicity of organocopper compounds, however, remains largely unknown. A 40-y-old man attempted suicide by ingesting some 50 ml of Sesamine fungicide. He immediately developed headache, vomiting and abdominal pain, followed by progressive dyspnea, cyanosis, dark urine and diarrhea. Severe methemoglobinemia and hemolysis were documented, and treatment with ascorbic acid and hydration was commenced. He was referred to our service 3 d later for methylene blue treatment. Despite the above treatment, his symptomatology persisted and it was not until 5 d post-ingestion that the implicated fungicide was identified as copper-8-hydroxyquinolate. BAL therapy and plasma exchange were instituted, which decreased his plasma hemoglobin from 1,300 mg/dL to 29.1 mg/dL, and lowered his methemoglobin level from 20.9% to 1.1%. His serum and urine copper concentration dropped from 238 microg/dL to 96 microg/dL and from 112 microg/dL to 16 microg/dL, respectively. He was discharged uneventfully 18 d post-ingestion. Pre-existing glucose-6-phosphate dehydrogenase (G6PD) deficiency as well as copper-induced inhibition of G6PD activity was documented during hospitalization. Organocopper compounds may cause prolonged hemolysis and methemoglobinemia through oxidative stress, especially among patients with G6PD deficiency. Antidotal therapy with methylene blue is not likely to be effective in this setting: treatment with intensive supportive measures and other therapeutic options, such as plasma exchange, should be sought.

An outbreak of footrot occurred in a flock of Corriedale sheep; 27 animals were treated with antibiotic and footbathed in a 5% copper sulfate solution. Being deprived of water for > 17 h, many sheep drank the footbath solution. After 6 h 16 sheep became ill with acute copper poisoning, 10 animals died within 10 h; 6 were severely ill and were sent to Veterinary Hospital, and 4 had mild signs and recovered without treatment. The sick sheep had anorexia, dullness, grinding teeth, moaning, rumen atony, dehydration, dark blue-green diarrheic feces and congested membranes. They were treated with 3.4 mg tetrathiomolybdate/kg body weight and lactated Ringer's solution iv, oral molybdate, sulfate, kaolin and pectin, and drenched with antacids. Two of the 6 sheep died during hospitalization. The ingestion of copper solution caused an intense gastrointestinal injury that resulted in ulcers, petechial and echymotic hemorrhages in the mucosa, mild hemolysis detected by microscopic hemoglobinuria and a lowered packed cell volume, severe hepatic injury that raised the AST and gammaGT blood values, and moderate kidney lesions with increasing serum blood urea and nitrogen creatinine levels.

Yew ( Taxus baccata) foliage was co-incubated with rumen fluid (RF) taken from fistulated cattle (Bos taurus), anesthetized white-tailed deer (Odocoileus virginianus) and O. virginianus killed by bow hunters. The first trial with live deer resulted in statistically significant 59% reduction of taxine A by deer RF and no reduction by cattle RF. The second intubation trial, in which half the samples were stopped after 12 h, resulted in slightly less taxine A reduction by deer (46%) and 12% reduction by cattle RF. RF obtained by hunters eQuipped with thermos bottles and trained to collect RF immediatey upon field dressing their deer caused the most (88-96%) taxine A destruction: cattle RF reduced 68-88% the toxin. Obtaining RF from freshly killed deer was less expensive and more consistently successful than taking RF by intubation of anesthetized deer. The greater ability of white-tailed deer RF to detoxify yew taxines may not entirely explain the advantage white-tailed deer have over cattle to surviveyew ingestions without toxic effects.

The use of a powder for poisoning sea fish off Lebanon is reported for the first time. The powder is prepared from the seeds of storax (Styrax officinalis L) and tubers of common cyclamen (Cyclamen persicum Mill.), both species growing wild in Lebanon. References to the properties of these species are provided.