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Previous studies have demonstrated that a novel source of ozone gas (O3) maybe used to chemically degrade numerous mycotoxins, including aflatoxin (AF) B1. Subsequent in vitro analyses demonstrated detoxification of AFB1, suggesting a potential method of remediate AF-contaminated grain. The objective of this study was to evaluate the capability of electrochemically produced ozone to degrade AFB1 in naturally contaminated whole kernel corn and confirm detoxification in turkey poults. Corn was procured from the southern coastal areas of Texas and HPLC revealed 1,220 +/- 73.3 ppb AFB1. Control and contaminated corn were treated for 92 h with O3 at 200 mg/min in 30 kg batches; greater than 95% reduction of AFB1 in contaminated corn was achieved. One-day-old female turkey poults were fed 1) control corn, 2) control corn + O3, 3) AFB1 corn, or 4) AFB1 corn + O3 mixed in rations (46% by wt.) and consumed ad libitum for 3 wk. When compared with controls, turkeys fed AFB1 corn had reduced body weight gain and relative liver weight, whereas turkeys fed control corn + O3 or AFB1 corn + O3 did not differ from controls. Furthermore, alterations in the majority of relative organ weight, liver discoloration, serum enzyme activity, hematological parameters, and blood chemistry caused by AFB1 were eliminated (no difference from controls) by treatment with O3. These data demonstrate that treatment of contaminated corn with electrochemically produced O3 provided protection against AFB1 in young turkey poults. It is important to note that treatment of control corn with O3 did not alter the performance of the turkey poults.

Previous studies with cyclopiazonic acid (CPA) have indicated that this mycotoxin strongly adsorbs onto the surface of a naturally acidic phyllosilicate clay (AC). The objective of this study was to determine whether AC (and similar adsorbents) could protect against the toxicity of CPA in vivo. Acidic phyllosilicate clay, neutral phyllosilicate clay (NC, or hydrated sodium calcium aluminosilicate), and a common zeolite (CZ, or clinoptilolite) were evaluated. One-day-old broiler chicks consumed diets containing 0 or 45 mg/kg CPA alone or in combination with 1% AC, NC, or CZ ad libitum from Day 1 to 21. Body weight, feed consumption, feed:gain, hematology, serum biochemical values, and enzyme activities were evaluated. Compared to controls, CPA alone reduced body weight at Day 21 by a total of 26% and resulted in a significantly higher feed:gain ratio. Toxicity of CPA was also expressed through increased relative weights of kidney, proventriculus, and gizzard. Also, there were some alterations in hematology, serum biochemical values, and enzyme activities. Treatment with inorganic adsorbents did not effectively diminish the growth-inhibitory effects of CPA or the increased weights of organs, although there was some protection from hematological, serum biochemical, and enzymatic changes produced by CPA. The results of this study suggest that in vitro binding of CPA to clay does not accurately forecast its efficacy in vivo; the reasons for this discrepancy are not clear, but they may be related to differences in clay binding capacity and ligand selectivity for CPA in vitro vs in vivo. Predictions about the ability of inorganic adsorbents to protect chickens from the adverse effects of mycotoxins should be approached with caution and should be confirmed in vivo, paying particular attention to the potential for nutrient interactions.

We conducted an epidemiological survey of antibiotic resistance in Salmonella recovered from market-age swine at five different Texas farms. These farms, which were visited between October 1997 and June 1998, were completely integrated, farrow-to-finish operations. Samples were taken from the lymph nodes and cecal contents at the time of slaughter. The Salmonella samples that were recovered were sent to the National Veterinary Services Laboratory for serotyping. Antibiotic resistance was determined using the Dispens-O-Disc Susceptibility Test System using 13 different antimicrobial agents that have been utilized in either veterinary medicine, human medicine, or both. Preliminary analysis of the first 183 samples out of approximately 400 Salmonella samples recovered indicated that 183 (100%) of the Salmonella samples were resistant to penicillin G, and 122 (66.7%) were resistent to chlortetracycline. Six (3.3%) were resistant to four antibiotics (chlortetracycline, penicillin G, streptomycin, and sulfisoxazole), and 25 (13.7%) were resistant to three antibiotics (chlortetracycline, penicillin G, and either streptomycin, sulfisoxazole, or ampicillin). Variation was seen between serotypes, with four out of five S. agona samples (80.0%) and two out of eight S. derby samples (25.0%) resistant to four antibiotics. Variation in antibiotic resistance also was seen between farms. There is an increasing concern about the prevalent usage of antibiotics in medicine and agriculture and the relationship this may have on emerging microbial resistance patterns; therefore, continued surveillance on antibiotic resistance in animal production is warranted.

Ceftiofur, a recently introduced antibiotic of the beta-lactam group, is rapidly converted to both free and protein-bound metabolites when administered by the prescribed procedure, intramuscular injection. Free metabolites retain antimicrobial activity and may be detected by antibiotic-screening tests based on antimicrobial activity. It is thus desirable to distinguish ceftiofur metabolites from other antibiotics. A multiresidue procedure for beta-lactams in milk was adapted for determination of free ceftiofur metabolites by collecting appropriate liquid chromatographic fractions during cleanup. Analysis of tissues from treated animals showed that the principal free metabolite was the desfuroylceftiofurcysteine conjugate.

Deacetyl diltiazem (M1) is a major metabolite of the widely used calcium antagonist diltiazem (DTZ). In order to study the pharmacokinetic and haemodynamic effects of this metabolite, M1 was administered as a single 5 mg kg-1 dose intravenously (i.v.) to New Zealand white rabbits (n = 5) via a marginal ear vein. Blood samples, blood pressure (SBP and DBP), and heart rate (HR) recordings were obtained from each rabbit up to 8 h, and urine samples for 48 h post-dose. Plasma concentrations of M1 and its metabolites were determined by HPLC. The results showed that the only quantifiable basic metabolite in the plasma was deacetyl N-monodesmethyl DTZ (M2). The t1/2 and AUC of M1 and M2 were 2.1 +/- 0.5 and 3.0 +/- 1.1 h, and 1300 +/- 200 and 240 +/- 37 ng h mL-1, respectively. The Cl and Clr of M1 were 60 +/- 10 and 0.81 +/- 0.63 mL min-1 kg-1, respectively. M1 significantly decreased blood pressure (SBP and DBP) for up to 1 h post-dose (p0.05), but had no significant effect on the heart rate (P0.05). The Emax and EC50 as estimated by the inhibitory sigmoidal Emax model were 20 +/- 18% 620 +/- 310 ng mL-1, respectively for SBP; 20 +/- 8.3% and 420 +/- 160 ng mL-1 for DBP.

The effects of feeding diets containing 100 mg moniliformin (M)/kg of feed from culture material and 16 mg deoxynivalenol (DON)/kg of feed from naturally contaminated wheat were evaluated in growing broiler chicks from 1 day to 21 days of age. Body weight (BW), body-weight gain, and feed consumption were decreased by feeding M and M plus DON diets. Relative heart weight was increased by the M diet, whereas relative weights of proventriculus, gizzard, and heart were increased by the M plus DON diet. The M diet increased alanine transferase and aspartate transaminase activities and creatinine concentration and decreased mean corpuscular volume, mean corpuscular hemoglobin, and mean corpuscular hemoglobin concentration (MCHC). The M and DON diet decreased glucose, hemoglobin, and MCHC. Histopathological lesions from the M diet were limited to the kidney and consisted of extensive renal tubular epithelial degeneration plus luminal mineralization. A moderation of the severity of lesions was seen in the tissues of the M plus DON-fed chicks, consisting of generally mild tubular epithelial degeneration. None of the parameters measured were affected by the DON diet. Results indicate additive or less-than-additive toxicity for most parameters when chicks were fed diets containing 100 mg M plus 16 mg DON/kg of feed. Although the concentration of M in this study was high compared with that reported for feedstuffs, additional information on the occurrence and toxicity of M will need to be collected in order to assess the importance of M to the poultry industry.

This study describes the epidemiology of injuries due to falls from horses in New Zealand. There were 54 fatalities from 1977 to 1986 (0.17 per 100,000 persons per year). There were 773 hospitalisations in 1987 (23.7 per 100,000 persons per year). Head injuries were predominant among both fatal and nonfatal injuries. The incidence of nonfatal head injury in the 10 to 19 age group was significantly higher than the incidence in all older groups (P = 0.003). Young people, particularly females, were the segment of the population most affected by the problem of falls from horses. Reference to data on horse-riding participation rates, however, did not indicate that young people were overrepresented in the series studied. Reference to the same data showed that the rate of hospitalisation due to falls from horses is comparable to the rate for injuries from playing rugby. The magnitude and severity of the problem indicates that there is a need need for helmet use, safe-riding practices, and further research.

This study was undertaken to determine whether isozyme-specific inhibitors of cAMP-selective phosphodiesterases (PDEs) induce bronchodilation without the cardiovascular side effects known to be produced by nonselective PDE inhibitors. The abilities of PDE inhibitors to reverse the bronchoconstriction induced by serotonin in a beta-blocked anesthetized dog were compared simultaneously with their effects on cardiac contractile force (+dP/dt), heart rate and blood pressure. Aminophylline and enprofylline, two antiasthma drugs with nonselective PDE inhibitory activity, produced dose-dependent (ED50S = 2.3 and 0.58 mg/kg, respectively) and complete (95-100%) bronchodilation accompanied by profound increases in cardiac force, tachycardia and decreases in blood pressure. Similar effects were observed with forskolin, a potent adenylate cyclase activator. Imazodan and CI-930 (inhibitors of the cGMP-inhibitable cAMP-selective PDE isozyme designated PDE-III) induced pulmonary and cardiovascular effects virtually identical to the nonselective PDE inhibitors, but with greater potency (ED50S = 0.02 and 0.04 mg/kg). In contrast, rolipram and Ro 20-1724 (inhibitors of a cGMP-insensitive cAMP-selective PDE isoform commonly designated PDE-IV) induced bronchodilation in the dog (ED50S = 0.007 and 0.63 mg/kg, respectively) without causing significant changes in cardiac force or heart rate, even after predosing dogs with forskolin. However, rolipram and Ro 20-1724 were less efficacious than the other inhibitors in that they induced only partial (50-60%) bronchodilation. The results suggest that canine respiratory muscle tension is regulated by both PDE-III and PDE-IV. Inhibitors of PDE-IV produce bronchodilation in the described model with minimal concomitant cardiac side effects.(ABSTRACT TRUNCATED AT 250 WORDS)

Summary1. SK 3818, N,N′,N′-triethylene-phosphoramide and SK 4614, N,N-diethyl-N′, N′-diethylenephosphoramide are both capable of retarding the growth of Sarcoma 180 in mice 24 hours and four days after implantation of tumor. Among the chemotherapeutic agents tested in our laboratory SK 3818 has shown the greatest effective dose range. 2. Histopathological examination of tumors of mice treated with SK 3818 and SK 4614 showed enlargement of cells with vacuolar degeneration of cytoplasm, enlargement of nuclei and nucleoli. Furthermore, the number of mitoses was decreased. Numerous cells showed nuclear alterations as commonly encountered during necrosis such as pyknosis, karyolysis and karyorrhexis. 3. Histopathological examination of organs of mice treated with SK 3818 and SK. 4614 revealed lesions similar to the ones occurring during administration of nitrogen mustards: intestinal damage and depletion of myeloid and lymphoid system with leucopenia (granulocytopenia and relative increase of mononuclear cells...

Nine cells lines--BHK-21, Vero, Aedes albopictus, A. aegypti (monolayer and howwow vesicles), A. w-albus, A. vittatus, Anopheles stephensi and Culex quinquefasciatus--were infected with small- and large-plaque (SP, LP) variants of chikungunya virus. Ross strain, and incubated at different temperatures. In the Aedes (29 plus or minus 1 degrees C) and the vertebrate cell lines (36 degrees C), infectivity titers of extracellular virus rapidly reached a peak; cytopathic effect (CPE) occurred only in the latter. In Anopheles cells (29 plus or minus 1 degrees C), infectivity titers increased very slowly to a peak at 10 days post-inoculation (p.i.); in Culex cells (29 plus or minus 1 degrees C or room temperature), persistence of virus only or no multiplication was observed. In infected A. albopictus, A. aegypti and A. w-albus carrier cultures, the SP variant continued to resemble the original stock virus in terms of mouse pathogenicity and plaque morphology in Vero cells, but the LP variant tended to modify toward the SP variant.

The present isolated tissue study was designed to quantitate the alpha-adrenoceptor agonist activity of AY- 30,191 (5-(1-hydroxy-2-amino-ethyl)-1H-indole-7-carboxamide) and a series of related compounds. AY-30,191 induced contractions in the rabbit aorta, which were blocked by prazosin. In the rat vas deferens, while clonidine inhibited the electrically induced twitch response, AY-30,191 caused a prazosin-sensitive augmentation. In the dog saphenous vein, rauwolscine was less effective than the combination of rauwolscine and prazosin in inhibiting the contractions induced by AY-30,191. Pretreatment of the dog saphenous vein with phenoxybenzamine reduced the response to AY-30,191. The addition of rauwolscine to phenoxybenzamine-treated tissues had no effect on the contractions to AY-30,191 remaining after phenoxybenzamine treatment. These results suggest that AY-30,191 is a selective alpha 1-adrenoceptor agonist. Optimal alpha 1-adrenoceptor agonist activity in the 1H-indole-7-carboxamide series was seen in compounds in which a) the indole ring and the ethylamine side chain were intact; b) the indole nitrogen was unsubstituted; and c) the carboxamide was present at the 7-position in the indole ring. Removal of the carboxamide decreased alpha 1-adrenoceptor activity and, more importantly, resulted in a loss of alpha 1-adrenoceptor selectivity. Replacement of the carboxamide in the 7 position with methanesulfonamide resulted in a decrease in activity but a retention of alpha 1-adrenoceptor selectivity, whereas the dimethylamino analog was nonselective and the phosphoramidic acid diethylester analog was inactive.(ABSTRACT TRUNCATED AT 250 WORDS)

1. Protein synthesis occurs at a high rate in the ovaries of maturing Octopus vulgaris and can be measured from the incorporation of [14C]leucine in vivo and in isolated groups of eggs in vitro. 2. Removal of the optic glands in vivo 1--3 days prior to testing markedly reduces amino acid incorporation in vivo or in vitro. After 5 days in vivo incorporation stops. 3. The rate of incorporation in vitro is increased by the addition of optic gland extract. 4. Analysis of the kinetics of leucine uptake and incorporation in vitro indicates that the hormone has an effect on the inward transport of leucine which is independent of its action on protein synthesis. 5. Electron-microscope studies of the follicle cells and ova show that the former are the site of protein synthesis. 6. Changes in either uptake or incorporation into protein by the follicle cells can be used as a qualitative biolobical assay for the optic gland hormone. Uptake is very easy to measure but incorporation is the more sensitive parameter. Either is potentially suitable as a quantitative assay for this and perhaps also for other molluscan gonadotropins.

A neutrophil-derived relaxing factor (NDRF) from oyster glycogen (OG)-elicited rat PMN, which causes an endothelium independent relaxation of rat aorta, and which is pharmacologically indistinguishable from endothelium-derived relaxing factor (EDRF) has been described. Experiments were designed to evaluate the presence of NDRF in PMN from rat -whole blood, -carrageenan pleurisy, -OG peritonitis, and guinea pig (GP) -OG peritonitis, as well as in OG-elicited rat macrophages (M phi). Significant vascular relaxing activity was found using rat PMN from OG peritonitis and carrageenan pleurisy, as well as from OG-M phi. Little or no activity was found in rat whole blood PMN or PMN from GP-OG peritonitis. These results suggest that NDRF activity may be expressed upon cellular migration to an inflammatory site in the rat, and may not be present in all species. Also, all inflammatory cells examined were capable of reversing EDRF-dependent relaxations when stimulated to produce superoxide anion suggesting a dual regulatory role for these cells on local vascular tone.

Summary Of 129 different arboviruses (134 strains) inoculated into cultures of the baby-hamster kidney-cell line BHK-21 (clone 13), all but five viruses produced cytopathic effect. The agents tested comprised members of 18 serogroups and a large number of ungrouped arboviruses. Comparative titrations of 10 viruses indicated that BHK-21 tissue culture, although slightly less sensitive than infant mice, could be of value as a routine assay system. Results were satisfactory in a limited series of BHK-21 tissue-culture neutralization tests. A total of 31 arboviruses, 10 in the larger serogroups and 21 mostly ungrouped, was tested in tissue culture for hemadsorption of guinea-pig erythrocytes. Results were negative except for one ungrouped virus, both strains of which were shown to be a myxovirus. The applicability of the hemadsorption test as a screening method in field laboratories is discussed.