Effects of elephant garlic volatile oil (Allium ampeloprasum) and T-2 toxin on murine skin.

Effects of elephant garlic (Allium ampeloprasum) volatile oil (GVO) and trichothecene (T-2) toxin were studied in Swiss albino mice. The animals were 1) topically applied GVO, 2) topically applied T-2 toxin, 3) topically applied GVO followed by T-2 toxin (GVO/T-2), and 4) T-2 toxin application followed by GVO (T-2/GVO) on the right footpad. All animals were observed by Langerhans cell enumeration and pathological changes of the footpad on days 1, 3, 5 and 7.

Chimeric dengue type 2/type 1 viruses induce immune responses in cynomolgus monkeys.

Chimeric dengue type 2/type 1 (DEN2/1) viruses, which contain the structural genes of the dengue-1 (16007) parental virus and the nonstructural genes of the DEN2-PDK53 virus, have been constructed. These DEN2/1 viruses induce high levels of DEN1 virus-specific neutralizing antibodies in mice. In this study, the DEN2/1 viruses induced DEN1 virus-specific neutralizing antibodies without the development of viremia in cynomolgus monkeys.

In vivo and in vitro studies on the morphological change in the monkey epidermal Langerhans cells following exposure to dengue 2 (16681) virus.

A direct comparison of skin Langerhans cell (LC) morphologic change following in vivo and in vitro exposure to dengue-2 (DEN-2) virus (16681) was performed in the monkey to investigate any differences in functional activity profiles. Time-lapse study of skin biopsy at the intradermal (id) virus injection sites, and thin skin sheets removed from the monkey with exposure to virus in culture medium, revealed a highly active migration of epidermal LCs in both sets of experimental specimens. The migration led to a relatively higher number of dendritic cells (DC) which appeared in active migrational profiles, in the superficial dermis.

Langerhans cell density and serological changes following intradermal immunisation of mice with dengue 2 virus.

After the introduction of the dengue-2 (16681) virus by intradermal (i.d.) injection into the footpads of mice, Langerhans cells (LCs) increased in numbers within 24 h at the site of injection and neutralising antibody developed.

Dengue-3 (16562) PGMK 33 vaccine: neurovirulence, viremia and immune responses in Macaca fascicularis.

Investigation of monkey neurovirulence of dengue-3 viruses (DEN-3, 16562) was undertaken to provide an evaluation of the relative safety of virus strain attenuated for potential use of live virus vaccine. Ten flavivirus-negative, cynomolgus monkeys (Macacafascicularis) were used in the test. The animals were inoculated intrathalamically, intraspinally and intramuscularly with DEN-3 PGMK 33 attenuated live virus vaccine (6 monkeys): parent virus (2) and control cell culture fluid (2).

A single dose-response effect of aflatoxin B1 on rapid liver cancer induction in two strains of rats.

To investigate rapid liver cancer induction in rats by aflatoxin B1 (AFB1), different single oral doses of AFB1 were given to 3 groups of 1-year-old Buffalo and Wistar rats. The animals were treated once and all survivors were killed 6 weeks later. Control animals received an equal volume of solvent (DMSO), and both groups of animals were maintained under identical conditions throughout the period of experiment.

Minimal dose and time protection by lindane (gamma-isomer of 1,2,3,4,5,6 hexachlorocyclohexane) against liver tumors induced by aflatoxin B1.

This study was carried out in order to investigate the minimal exposure to lindane (LD, 99.72% gamma isomer of 1,2,3,4,5,6 hexachlorocyclohexane), a chlorinated hydrocarbon insecticide, required to protect against liver tumor induced by aflatoxin B1 (AFB1). Materials fed to Buffalo strain rats were as follows: LD 100 ppm; AFB1 1 ppm, LD 100 ppm plus AFB1 1 ppm; and control basal diet.

Reducing effects of rodent malaria on hepatic carcinogenesis induced by dietary aflatoxin B1.

The present study was undertaken to evaluate the effects of Plasmodium berghei infection on the development of liver tumors induced in male Buffalo rats by aflatoxin B1 (AFB1). Intraperitoneal (i.p.

Dengue-4 vaccine: neurovirulence, viraemia and immune responses in rhesus and cynomolgus monkeys.

A dengue 4 (DEN-4, strain 1036-PDK 48) vaccine attenuated by passage in primary dog kidney cells was tested using rhesus (Macaca mulatta) and cynomolgus (M. fascicularis) monkeys to determine its safety, potency, and immunogenicity. 14 rhesus monkeys were divided into 3 groups: group 1, 2 animals given control culture fluid; group 2, 2 animals given DEN-4 parental virus; group 3, 10 animals given DEN-4 vaccine virus.

Neurovirulence detection of dengue virus using rhesus and cynomolgus monkeys.

The results of a comparative study of neurovirulence of dengue type 1 virus in two species of Old World monkeys, viz. rhesus monkeys (Macaca mulatta) and cynomolgus monkeys (Macaca fascicularis) are reported. In the present study, parental dengue type 1 (16007) and its vaccine viruses were tested by intrathalamic, intramuscular and intraspinal injections in these two species of monkey.

Neurovirulence effects of dengue-2 viruses on the rhesus (Macaca mulatta) brain and spinal cord.

Vaccines prepared from attenuated virus can cause symptomatic viral infection of the central nervous system. In the present study, dengue-2 parental and its live attenuated viruses were tested by intrathalamic and intraspinal injections in rhesus monkeys. The dengue-2 viruses were found to be only very weakly neurovirulent when injected directly into the brain or spinal cord of rhesus monkeys.

The neurovirulence of flaviviruses in crab-eating monkeys (Macaca fascicularis).

The neurovirulent properties of attenuated dengue-2 and yellow fever (YF) vaccines, dengue-2 (DEN-2) and Japanese encephalitis (JE) viruses were studied in crab-eating monkeys (Macaca fascicularis). Number of central nervous system sites (as proportion affected) with neurovirulence (NV) lesions were compared. The results indicate that these monkeys reliably developed NV-lesion when inoculated with either JE or YF vaccine viruses (87%).

Blood value changes in flavivirus-inoculated Macaca fascicularis monkeys.

Blood values were analysed in eighteen cynomolgus monkeys on pre-and post-neurovirulence testing of dengue-2 and yellow fever vaccine viruses, dengue-2 parental and Japanese encephalitis viruses. Certain changes between blood chemistry, hematology and serology were observed and briefly discussed.

Enhancing effects of rodent malaria on aflatoxin B1-induced hepatic neoplasia.

The interaction between aflatoxin and malaria was tested for its usefulness as a model for hepatic tumor induction in rats. Male Buffalo rats which received aflatoxin B1 (AFB1) followed by Plasmodium berghei infection developed more preneoplastic lesions in the liver compared to those given AFB1 alone. No preneoplastic lesions were found in the liver of control and malarial-treated animals.

Enhancing effects of dimethylnitrosamine on aflatoxin B hepatocarcinogenesis in rats.

In a study of possible enhancing effects of dimethylnitrosamine (DMN) on aflatoxin B1 (AFB1) hepatocarcinogenesis, male Buffalo strain rats were fed diets containing 1 ppm AFB1, 25 ppm DMN, and a combination of 1 ppm AFB1 and 25 ppm DMN (AFB1 + DMN). The diets were replaced by chow pellets after 6 months, and animals were killed 3, 6, 9 and 12 months after the onset of the experiment. In the untreated control group animals were free of hepatocellular carcinoma but the treated groups fed AFB1, DMN and AFB1 plus DMN developed hepatic lesions ranging from multiple cysts, altered cell foci and neoplastic nodules to hepatocellular carcinomas.

Aflatoxicosis in horses.

Two episodes of acute aflatoxin poisoning in horses suggest that horses are susceptible to the toxic effects of this mycotoxin. Lesions associated with exposure to aflatoxin included encephalomalacia of cerebral hemispheres, fatty degeneration, necrosis, bile duct hyperplasia, fibrosis of the liver, fatty infiltration of the kidney, hemorrhagic enteritis, and myocardial degeneration. Hypoglycemia, hyperlipidemia, and depletion of lymphocytes accompanied these lesions.

Alpha benzene hexachloride inhibition of aflatoxin B1-induced hepatocellular carcinoma. A preliminary report.

Alpha benzene hexachloride protected against the development of liver carcinoma in male albino Fisher rats ingesting aflatoxin B1.