Veterinary and human toxicology最新文献

Despite the well-founded reputation of plants of the genus Taxus as being amongst the most toxic plants for domestic livestock in the US, there are surprisingly few published case reports of yew poisoning in horses. This report documents 2 acute fatalities in horses in the central Willamette Valley, OR associated with the consumption of Taxus sp. The predominant features of the intoxication were peracute death, with no signs of struggling or convulsions, in otherwise fit and well managed adult horses. The most significant gross necropsy findings were limited to pulmonary congestion and hemorrhage, suggestive of acute circulatory disturbance. A diagnosis of Taxus sp poisoning was confirmed on the basis of a history of potential exposure, by the identification of yew leaves in the gastric contents of the horses, and by the subsequent identification of yew clippings in the pasture. The literature relevant to Taxus sp poisoning in horses is reviewed.

An education program was implemented at a regional poison center to increase use of a new nationwide 800 number (800/222-1222) in counties in our region that had low rates of utilization. We identified 10 counties with the lowest utilization rates and provided textbook covers to the elementary and secondary schools in these areas. The covers contained the poison help logo and information about what to do if a poisoning occurs. Changes in utilization rate for these counties were compared to similar counties over the course of a year. Utilization rates increased in both sets of counties over the study period, but there was no significant difference (p = 0.84) between the 2 groups. Use of textbook covers to increase awareness and utilization made little impact beyond our normal efforts and was not cost-effective.

This study covers 1975 to 2003 with measurements of lead in soil (n = 24), hay (n = 259), silage (n = 35) and blood of cows (n = 1279) from farms (n = 1 to 14) situated 1 to 10 km around a lead smelter. Until 1978, when protective filters were installed in the plant chimneys, the farms had been exposed to heavy industrial-metallurgic effluent. Early measurments (1968 to 1975) high lead (> 600.0 mg lead/kg) in the topsoil, and continuing measurements (1981 to 2003) showed no significantly decreased lead after the installation of filters; however, mean lead in hay samples gradually decreased. In 1975 lead concentrations in 4 samples of hay were 227.0 to 953.0 mg/kg DM. In 2002 (n = 12) mean lead concentrations were about 100-fold lower (5.6 +/- 3.3 mg lead/kg DM). A similar trend of decreasing lead concentrations occurred also in the blood of cows. In 1975 (n = 9) average lead concentration was 1.2 +/- 0.6 mg/kg whole blood, while in 2002 (n = 58) it was about 20-times lower (0.07 +/- 0.005 mg/kg). This significant decrease in lead concentration may be attributed to sanitation of the major source of industrial emission of lead gasses and dust by installation of bag filters to the plant chimneys in 1978. After 1982 mean cow lead blood concentrations were within normal reference values (< 0.250 mg of lead/kg). However, during the last 10y mean lead concentrations have still been 1- to 2-fold above the values measured in blood (n = 32) from 3 control areas in Slovenia. Cattle blood levels proved a good bioindicator of environmental contamination. Monitoring lead in the blood of animals on farms near the smelter should continue because the persistence of lead in topsoil is the main problem in this area.

Fentanyl patches offer a novel, but increasingly common method of drug abuse. We describe a patient who developed severe respiratory dysfunction after fentanyl patch abuse via insufflation, naloxone administration and aspiration. After other aggressive interventions failed to correct worsening hypoxemia, extracorporeal membrane oxygenation (ECMO) was initiated and led to complete recovery. To our knowledge, this is the 1st reported case of ECMO being used to correct severe pulmonary dysfunction associated with opioid abuse. The risks associated with naloxone administration are discussed.

Sixteen fatal dog envenomations by the snake Vipera palaestinae over a 14-y period are described. Most envenomations occurred during the late night hours in the warm months, and 8/16 dogs were bitten on the limbs. The most frequent clinical signs upon admission were soft tissue swelling and edema, local pain, depression, bleeding, lameness, dyspnea, and 6 dogs were in shock. Thrombocytopenia was present in 14/16 cases and increased hematocrit (13/16) and hemoglobin (9/16) concentration were the most common hematological abnormalities upon admission. Biochemical abnormalities included increased activities of muscle enzymes and alkaline phosphatase, hypocalcemia, and hypocholesterolemia. Creatine kinase activity was markedly increased in 2 dogs. During hospitalization serious complications in many dogs were disseminated intravascular coagulation, acute renal failure, seizures, cardiac arrhythmias, acute necrotizing pancreatitis and severe laryngeal edema; these required intensive and expensive therapies. Specific antivenin (10 ml) administered to 8/16 dogs did not prevent death. Glucocorticosteroids were given in 8 cases; however, their use was associated with complications. Four dogs suffered sudden death, 2 of which died 1-2 d after discharge. Necropsy performed on 3/16 dogs found soft tissue swelling and local bleeding at the envenomation sites as well as bleeding in several distal body organs and tissues.

One hundred and ninety-two crossbred pigs (barrows, Duroc x Landrace x Yorkshine, initial weight 27.6 kg) were used to evaluate the effects of montmorillonite nanocomposite (MNC) on cadmium (Cd) retention in tissues of growing pigs. The animals were randomly assigned to 2 supplementations of Cd (0 or 10 mg/kg) and 2 levels of MNC (0 or 0.5%) in a 2x2 factorial arrangement. Each group was fed corn-soybean basal diets and consisted of 3 replications of 16 pigs. The feeding experiment lasted 83 d. Pig growth performances decreased significantly by addition of 10 mg Cd/kg (p<0.05) and improved with supplementation of MNC (p<0.05). Addition of MNC with Cd decreased Cd retentions in muscle, liver, kidney, spleen, thymus and lymphaden of pigs (p<0.05). MNC also decreased tissue Cd residues of pigs fed the diet without added Cd (p>0.05). There were decreased iron levels and increased copper levels in serum and liver of 10 mg Cd/kg treatment (p<0.05). Zinc content in serum and liver was not affected by the addition of Cd (p>0.05). Serum and liver iron, copper and zinc concentrations of pigs fed MNC without added Cd were unaffected by MNC (p>0.05).

Epidemiological, clinical and pathological aspects of an unreported plant poisoning are described in sheep from southern Brazil. The disease occurred during the summer of 2003/2004 in 173 crossbred sheep with morbidity, mortality and lethality rates respectively of 31.8%, 8.1%, and 25.5%. Affected sheep were reluctant to move; when forced to walk they had stiff uncoordinated gaits, dragged their toes and bumped into objects in their path. When standing they assumed a wide base position with the legs widely spread apart. Increased respiratory rates, laborious breathing and cyanosis were marked in affected sheep that died. The experimental feeding of 2 sheep with the fruits of Eythroxylum argentinum reproduced the clinical disease. Except for consistent findings of distended bladder and the presence of E. argentinum undigested seeds in the abomasum and rumen in 4 necropsied sheep, no significant necropsy and histopathological findings were found. It was concluded that the ingestion of fruits of E. argentinum was the cause of this disease in sheep.

Accidental hydrofluoric acid (HF) splashes often occur in industrial settings. HF easily penetrates into tissues by initial acid action allowing fluoride ions to penetrate deeply, chelating calcium and magnesium. Resultant hypocalcemia and hypomagnesemia can be fatal. This report describes the utilization of Hexafluorine--a hypertonic, amphoteric, chelating decontamination solution--in workplaces where water decontamination followed by calcium gluconate inunction failed to prevent HF burns and systemic toxicity. Between 1998 and 1999, 16 cases of ocular and dermal HF splashes with either 70% HF or 6% HF/15% nitric acid (HNO3) were decontaminated with Hexafluorine at the worksite. HF burns did not develop and medical treatment other than initial decontamination was not reQuired in 12/16 (75%). In 7/16 (44%) cases, lost work time corresponded to duration of hospital observation (mean < 1 d).

We describe 4 cases of delayed extrapyramidal disorder following acute dichlorvos poisonings. All patients were seriously poisoned since all exhibited profound coma and respiratory failure, and they were all tracheally intubated and mechanically ventilated. On admission, plasma cholinesterase activity was greaty decreased, < 10 micromol/ml/h at 37 C in all patients (< 10% of normal for our laboratory). Extrapyramidal symptoms occurred between 5 and 15 d and were characterized by dystonia of arms and legs, resting tremor, cogwheel rigidity, and hypereflexia. With bromocriptine therapy the features of extrapyramidal syndrome disappeared progressively with complete recovery in all patients. Our observations suggest a delayed extrapyramidal syndrome should be taken into account during the course of acute dichlorvos organophosphate poisonings.