Search results for "toxin"
showing 10 items of 1434 documents
Does low concentration mycotoxin exposure induce toxicity in HepG2 cells through oxidative stress?
2020
The purpose of this study was to determine whether exposure to low concentrations of deoxynivalenol (DON), T-2 toxin (T-2) and patulin (PAT) in a human hepatocellular carcinoma cell line (HepG2) exerts toxic effects through mechanisms related to oxidative stress, and how cells deal with such exposure. Cell viability was determined by the MTT and protein content (PC) assays over 24, 48 and 72 h. The IC
IMMUNOGENICITY OF AN ACELLULAR PERTUSSIS VACCINE COMPOSED OF GENETICALLY INACTIVATED PERTUSSIS TOXIN COMBINED WITH FILAMENTOUS HEMAGGLUTININ AND PERT…
1993
We studied the immunogenicity of an acellular pertussis vaccine composed of genetically detoxified pertussis toxin (PT-9K/129G), filamentous haemagglutinin, and a 69-kilodalton protein, pertactin, in 30 children aged 12 to 24 months and in 80 infants aged 2 to 4 months. A significant increase of the neutralizing titer and of the titers against pertussis toxin, filamentous hemagglutinin, and pertactin, as determined by enzyme-linked immunosorbent assay, was achieved after three doses of vaccine in all the children; a significant increase of these antibody titers was obtained in 100%, 96.1%, 93.5%, and 98.7% of the infants, respectively.
Inhibitory influence of chromogranin A N-terminal fragment (vasostatin-1) on the spontaneous contractions of rat proximal colon
2005
Very little is known about the role played by CGA and its fragments in the gastrointestinal physiology. We have studied the role of CGA N-terminal fragments in the regulation of intestinal smooth muscle contractility by measuring the influence of recombinant CGA 1-78 (VS-1) and synthetic CGA 7-57 peptides on the spontaneous mechanical activity of rat proximal colon in vitro. The mechanical activity was recorded as changes in the intraluminal pressure. VS-1 (0.1-30 nM) and CGA 7-57 (10-300 nM) produced concentration-dependent inhibitory effects, characterized by a progressive decrease in the mean amplitude of circular muscle spontaneous contractions, without affecting the resting tone. The r…
Effect of polybrominated biphenyls on bromobenzene lethality in mice.
1977
Polybrominated biphenyls (PBBs) are inducers of hepatic microsomal cytochrome P450 and P1 450 in rats and mice. The purpose of this study was to determine, in mice, the effect of PBBs on the lethality of the hepatotoxin bromobenzene. Female NMRI mice were administered a single ip injection of 150 mg/kg PBBs and other mice received phenobarbital (PB), 100 mg/kg daily for 3 days, or 3‐methylcholanthrene (MC), 20 mg/kg daily for 3 days. At 24 hr after PB or MC and 24, 48, and 96 hr after PBBs animals received 3,150 mg/kg bromobenzene ip (LD85) and the time to death was recorded. Both PB and MC enhanced bromobenzene lethality and decreased the median time to death (LT50) from 23 hr in controls …
Effect of priming with diphtheria and tetanus toxoids combined with whole-cell pertussis vaccine or with acellular pertussis vaccine on the safety an…
1995
Objective: To evaluate the safety and the immunogenicity of a booster dose of recombinant acellular pertussis vaccine combined with diphtheria and tetanus toxoids (DTaP, Biocine SpA) in 15- to 21-month-old children primed in infancy with either whole-cell diphtheria-tetanus-pertussis (DTwP) vaccine or DTaP vaccine. Design: Open-label second phase of a double-masked, controlled trail, with masked analysis of serum samples. Participants and setting: Three hundred fifty children, 15 to 21 months of age, who had been primed at 2, 4, and 6 months of age with either three doses of DTaP vaccine (n = 173) or DTwP vaccine (n = 177). The children were enrolled in eight vaccination centers in Italy. I…
Insect Immune Evasion by Dauer and Nondauer Entomopathogenic Nematodes
2021
The immune response of animals, including insects, is overcome by some parasites. For example, dauer larvae (DL) of the obligate entomopathogenic nematodes (EPNs) Heterorhabditis and Steinernema can invade insects, evade their defenses, and cause death. Although DL were long assumed to be the only infective stage of nematodes, recent reports suggest that L2-L3 larvae of facultative EPNs are also capable of killing insects. There are no studies, to our knowledge, about the role of nonimmunological barriers (the exoskeleton and its openings) in avoiding infection by DL and L2-L3 larvae, or whether these larval stages evade the host immune system in the same way. The objective of this study wa…
D2R striatopallidal neurons inhibit both locomotor and drug reward processes.
2009
The specific functions of dopamine D(2) receptor-positive (D(2)R) striatopallidal neurons remain poorly understood. Using a genetic mouse model, we found that ablation of D(2)R neurons in the entire striatum induced hyperlocomotion, whereas ablation in the ventral striatum increased amphetamine conditioned place preference. Thus D(2)R striatopallidal neurons limit both locomotion and, unexpectedly, drug reinforcement.
Evaluation of Mycotoxins in Infant Breast Milk and Infant Food, Reviewing the Literature Data
2021
In this review, an analysis focusing on mycotoxin determination in infant breast milk and infant food has been summarised for the last fifteen years of research focused on the intended population group of 1–9 months. The objective was to know the level of exposure of the child population to an estimated daily intake (EDI) of mycotoxins from the consumption of habitual foods. The EDI was compared with the tolerable daily intake (TDI) established by EFSA to estimate risk. In breast milk, the high prevalence and levels were for samples from Africa (Egypt and Tanzania) with aflatoxin M1 (1.9 μg/L and 10%), and Asia (Iran) with ochratoxin-A (7.3 μg/L and 100%). In infant formulas, high incidence…
Occurrence of mycotoxins in refrigerated pizza dough and risk assessment of exposure for the Spanish population.
2016
Mycotoxins are toxic metabolites produced by filamentous fungi, as Aspergillus, Penicillium and Fusarium. The first objective of this research was to study the presence of mycotoxins in 60 samples of refrigerated pizza dough, by extraction with methanol and determination by liquid chromatography associated with tandem mass spectrometry (LC-MS/MS). Then, the estimated dietary intakes (EDIs) of these mycotoxins, among the Spanish population, was calculated and the health risk assessment was performed, comparing the EDIs data with the tolerable daily intake values (TDIs). The mycotoxins detected in the analyzed samples were aflatoxin B1 (AFB1), aflatoxin B2 (AFB2), aflatoxin G1 (AFG1), zearale…
Review on the toxicity, occurrence, metabolism, detoxification, regulations and intake of zearalenone: An oestrogenic mycotoxin
2005
Zearalenone (ZEA) is a mycotoxin produced mainly by fungi belonging to the genus Fusarium in foods and feeds. It is frequently implicated in reproductive disorders of farm animals and occasionally in hyperoestrogenic syndromes in humans. There is evidence that ZEA and its metabolites possess oestrogenic activity in pigs, cattle and sheep. However, ZEA is of a relatively low acute toxicity after oral or interperitoneal administration in mice, rat and pig. The biotransformation for ZEA in animals involves the formation of two metabolites alpha-zearalenol (alpha-ZEA) and beta-zearalenol (beta-ZEA) which are subsequently conjugated with glucuronic acid. Moreover, ZEA has also been shown to be h…