The median 96-h lethal zinc concentration (LC50) was 439 microg Zn/L (hardness of 154 mg/L as CaCO3) for feral mottled sculpin (Cottus bairdi), decreasing to a median incipient lethal level of 266 microg Zn/L after 13 d. The 30-d chronic value was 255 microg Zn/L. The acute toxicity-hardness (ln-ln) slope of 1.022 exceeded that of the current U.S. Environmental Protection Agency zinc criteria. ...

The ƒ¿-toxin of Clostridium perfringens (werchii) contains both the lethal and hemolytic activities. It was identified as phospholipaseC (EC 3.1.4.3) catalyzing the hydrolysis of lecithin to a diglyceride and phosphorylcholine (Macfarlane and Knight, 1941). Pastan et al. (1968) separated the phospholipaseC of C. perfringens into two fractions, one preferentially hydrolyzing sphingomyelin to cer...

The ability of bacterial lipopolysaccharide (LPS) to enhance the toxicity of Shiga-like toxin II (SLT-II) was investigated in rabbits and mice. Rabbits were continuously infused with 0.5 50% lethal dose (LD50) of SLT-II per day. Rabbits that received a 30-micrograms/kg dose of LPS (0.02 LD50) on day 3 of infusion were significantly more likely to die than were rabbits receiving SLT-II only. Rab...

Previous studies have demonstrated that interleukin 1 (IL-1) can protect most mice from the acute lethal toxicity mediated by high doses of radiation and/or some chemotherapeutic drugs. The results presented herein demonstrate that the pretreatment of mice with recombinant human interleukin 1 alpha (rhIL-1 alpha) protects mice from the lethal effects of several myelotoxic chemotherapeutic drugs...

AIM To investigate the role of endotoxin in synergy between bacterial toxins associated with sudden infant death syndrome (SIDS). METHODS Extracellular toxins of 13 isolates of Staphylococcus from SIDS victims and matched healthy infants were tested for lethal toxicity in chick embryos with and without standard endotoxin (used at 1.00 ng/embryo). Endotoxin and toxins from staphylococci were u...

against COOP4-induced impairment of renal function in mats.At the same time, plasma clearance and urinary excme tion of platinum were essentially unaltered by diuretic administration. If plasma and urine platinum disposition reflects the disposition of the cytotoxic form(s) of COOP, then the above findings suggest that diuretic administration should result in decreased renal toxicity of COOP wi...

The pathological actions of anthrax toxin require the activities of its edema factor (EF) and lethal factor (LF) enzyme components, which gain intracellular access via its receptor-binding component, protective antigen (PA). LF is a metalloproteinase with specificity for selected mitogen-activated protein kinase kinases (MKKs), but its activity is not directly lethal to many types of primary an...

In this study, the lethal toxicity, behavioral responses and hematotoxicity of formulated chlorpyrifos on Clarias gariepinus was evaluated. C. gariepinus fingerlings were exposed to 0.2 mg/L, 0.25 mg/L, 0.3 mg/L, 0.35 mg/L and 0.4 mg/L of the active ingredient chlorpyrifos to determine the lethal concentrations and behavioral effects. C. gariepinus juveniles (38.84±7.67g) were then exposed to 0...

In this study, the lethal toxicity, behavioral responses and hematotoxicity of formulated chlorpyrifos on Clarias gariepinus was evaluated. C. gariepinus fingerlings were exposed to 0.2 mg/L, 0.25 mg/L, 0.3 mg/L, 0.35 mg/L and 0.4 mg/L of the active ingredient chlorpyrifos to determine the lethal concentrations and behavioral effects. C. gariepinus juveniles (38.84±7.67g) were then exposed to 0...

Explanation.................................................................................................. 149 Evaluation for acceptable daily intake......................................................... 150 Biochemical aspects........................................................................... 150 Absorption, distribution and excretion ....................................... 150 B...