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1.
Artigo em Inglês | MEDLINE | ID: mdl-29040049

RESUMO

In February 2014 a new law was approved by the Israeli parliament, namely the Control of Animal Feed Law. The law intends to regulate the production and marketing of animal feed. In preparation for the law's implementation in 2017, we have assessed the current feed and food safety challenges in Israel in recent years in association with the presence of common undesirable contaminants in various common feed and food commodities. Tight collaboration between regulatory authorities and feed/food industry, enhanced feed and food quality monitoring, transparency of survey results and readily accessible and reliable information for the public about health hazards of chemical contaminants, will guarantee the safety and quality of food and feed.


Assuntos
Ração Animal/estatística & dados numéricos , Contaminação de Alimentos/estatística & dados numéricos , Indústria de Processamento de Alimentos/tendências , Política Nutricional/tendências , Animais , Inocuidade dos Alimentos/métodos , Substâncias Perigosas , Humanos , Israel , Medição de Risco
2.
Food Chem ; 219: 459-467, 2017 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-27765252

RESUMO

Sorghum ergot is a disease caused commonly by C. africana. In 2015, ergot was identified for the first time in sorghum fields in Israel, leading to measures of eradication and quarantine. The aims of the study were to identify the ergot species by molecular and ergot alkaloid profile analysis, to determine the ergot alkaloid profile in pure honeydew and in infected sorghum silages and to estimate the safety of sorghum silages as a feed source. C. africana was rapidly and reliably identified by microscopical and molecular analysis. Dihydroergosine was identified as the major ergot alkaloid. Dihydrolysergol and dihydroergotamine were identified for the first time as significant ergot alkaloid components within the C. africana sclerotia, thereby providing for the first time a proof for the natural occurrence of dihydroergotamine. The sorghum silages were found to be safe for feed consumption, since the ergot alkaloids and the regulated mycotoxins were below their regulated limits.


Assuntos
Claviceps/química , Alcaloides de Claviceps/análise , Doenças das Plantas/microbiologia , Sorghum/microbiologia , Grão Comestível/microbiologia , Ergotaminas/análise , Israel
3.
Clin Pharmacol Ther ; 56(5): 471-6, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7955810

RESUMO

The effect of fluvoxamine on the pharmacokinetics of diazepam and metabolically derived N-desmethyl-diazepam was investigated in eight healthy volunteers. Each subject received a single oral dose of diazepam (10 mg) in a control session and on the fourth day of a 16-day treatment with fluvoxamine maleate (100 to 150 mg daily). Compared with the control session, concurrent fluvoxamine intake was associated with increased mean peak plasma diazepam concentrations (from 108 to 143 ng/ml, geometric means, difference not significant), with a marked reduction in apparent oral diazepam clearance (from 0.40 to 0.14 ml/min/kg; p < 0.01) and with a prolongation in diazepam half-life (from 51 to 118 hours; p < 0.01). Although peak plasma N-desmethyldiazepam levels were similar in the two sessions, the time required for the metabolite to reach a peak was longer during fluvoxamine intake than in the control session (206 versus 62 hours; p < 0.01). N-Desmethyldiazepam area under the plasma concentration-time curve values were also significantly increased during fluvoxamine treatment. These data suggest that fluvoxamine inhibits the biotransformation of diazepam and its active N-demethylated metabolite. The magnitude of this interaction is likely to have considerable clinical significance.


Assuntos
Diazepam/farmacocinética , Fluvoxamina/farmacologia , Adulto , Biotransformação , Diazepam/metabolismo , Feminino , Fluvoxamina/efeitos adversos , Humanos , Masculino , Nordazepam/sangue
4.
Clin Pharmacol Ther ; 61(4): 442-9, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9129561

RESUMO

OBJECTIVE: To investigate the pharmacokinetics of the four stereoisomers of valnoctamide, a mild tranquilizer endowed with anticonvulsant properties. METHODS: Racemic valnoctamide, 400 mg, was administered orally to seven healthy subjects and to six patients with epilepsy stabilized with long-term carbamazepine therapy. In the patients with epilepsy, valnoctamide kinetics was also reassessed after 8-day oral dosing at a dosage of 600 mg daily. Plasma samples were assayed by gas chromatography-mass spectrometry with use of a capillary column coated with chiral stationary phase that enabled baseline resolution of the four stereoisomers, designated hereafter as A, B, C, and D (where A and C, together with B and D, represent enantiomeric pairs). RESULTS: In healthy subjects, stereoisomers A, C, and D showed similar kinetics, with an apparent oral clearance (CL/F) of about 4 1/2 L/hr, a half-life (t1/2) of about 10 hours, and an apparent volume of distribution (VSS/F) of about 65 L. However, stereoisomer B showed a much higher clearance (8.7 +/- 0.9 L/hr) and a shorter t1/2 (5.8 hours). For all stereoisomers, CL/F values in patients with epilepsy were about tenfold higher than those found in healthy subjects. Compared with healthy subjects, patients with epilepsy also showed shorter t1/2 values and higher VSS/F values for each of the stereoisomers. After 7-day dosing, CL/F values at steady state were lower than those determined in the same patients after a single dose. CONCLUSIONS: Valnoctamide exhibits enantioselectivity and diastereoselectivity, an observation that may have important practical implications if pharmacodynamic differences between stereoisomers are also found. The observed pharmacokinetic differences between healthy subjects and patients with epilepsy are likely to be related to induction of metabolism of valnoctamide stereoisomers by carbamazepine.


Assuntos
Amidas/farmacocinética , Ansiolíticos/farmacocinética , Anticonvulsivantes/farmacocinética , Epilepsia/sangue , Administração Oral , Adulto , Amidas/administração & dosagem , Amidas/sangue , Ansiolíticos/administração & dosagem , Ansiolíticos/sangue , Anticonvulsivantes/administração & dosagem , Anticonvulsivantes/sangue , Área Sob a Curva , Esquema de Medicação , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , Valores de Referência , Estereoisomerismo
5.
Biochem Pharmacol ; 42(4): 949-51, 1991 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-1867649

RESUMO

HT-2 toxin was the sole metabolite formed when T-2 toxin was treated with homogenate from brain without its blood content. Homogenate from brain with its full blood content produced--besides HT-2 toxin--T-2 triol, neosolaniol, 4-deacetylneosolaniol and T-2 tetraol, i.e. the same metabolites formed by incubation of T-2 toxin with whole rat blood.


Assuntos
Encéfalo/metabolismo , Toxina T-2/metabolismo , Animais , Hidrolases/metabolismo , Hidrólise , Masculino , Ratos , Especificidade por Substrato , Tricotecenos/metabolismo
6.
Physiol Behav ; 69(3): 309-15, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10869597

RESUMO

This study investigated the sexual attraction of female blind mole rats to four groups of male mole rats: (a) intact males raised in captivity; (b) intact males trapped in the field; (c) captive males injected with testosterone; (d) captive castrated males. In the first part we measured blood testosterone, androstenedione, and dihydrotestosterone (DHT) levels, by radioimmunoassay; and urine testosterone levels, measured by GC-MS. The second part examined the relationship between urine testosterone levels in males and their attractiveness to females. Higher blood and urine testosterone levels were found in the field animals and in those injected with testosterone compared to captive intact or castrated animals: urine testosterone levels in the two other groups were not detectable. Blood androstenedione levels were also higher in the field animals and in those injected with testosterone compared to captive intact or castrated mole rats. Blood dihydrotestosterone levels were not detectable in all four experimental groups. Female mole rats chose to spend a longer period of time next to males with high blood and urine testosterone levels and high blood androstenedione levels than next to those with lower levels of these hormones. Because courtship and sexual behavior are influenced both by high levels of blood and urine testosterone and high levels of blood androstenedione, we suggest that the low levels of courtship and other sexual behavior in captive mole rats may be related to the lack of female attraction to these males, which display low levels of all three parameters.


Assuntos
Comportamento Sexual Animal/fisiologia , Testosterona/urina , Androstenodiona/sangue , Animais , Di-Hidrotestosterona/sangue , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Masculino , Ratos-Toupeira , Orquiectomia , Testosterona/sangue
7.
Toxicol Lett ; 153(1): 99-107, 2004 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-15342086

RESUMO

A novel non-destructive sampling approach is described for the identification of food matrices contaminated with deoxynivalenol and other mycotoxins. This technique is different from currently applied sampling procedures for this purpose and is based on the principle that surface material from the tested goods is collected on a filter and brought to chemical or spectroscopic analysis. This approach has been applied to several matrices and mycotoxins, with a focus on those mycotoxin-matrix combinations that are of main relevance due to current or future legislation. Tests were carried out with a facility that has been shown to be suitable to process large quantities of materials at points of transaction, such as harbour. Further experiments with a small sampling lance prototype showed that analytical results from the chemical analysis of the tested goods can be correlated with the results obtained with this novel sampling procedure.


Assuntos
Técnicas de Química Analítica/métodos , Contaminação de Alimentos/análise , Micotoxinas/análise , Cromatografia Líquida de Alta Pressão/métodos , Espectrofotometria/métodos
8.
J Pharm Sci ; 79(6): 548-51, 1990 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2395102

RESUMO

Verrucarol is a simple trichothecene which is structurally related to T-2 and HT-2 toxins. Several macrocyclic trichothecenes which are ester derivatives of verrucarol possess antitumor activity. The pharmacokinetics of verrucarol has been studied in eight dogs following iv and oral administrations (0.4 and 0.8 mg/kg, respectively). The iv study showed that verrucarol has a mean (+/- SD) clearance of 11 +/- 5.5 mL/min/kg, a volume of distribution of 1.2 +/- 0.6 L/kg, and a terminal half-life of 1.6 +/- 0.5 h. Following oral administration, the absolute bioavailability of verrucarol was 44 +/- 33%, and its terminal half-life was similar to that obtained after iv administration. In comparison with T-2 and HT-2 toxins, verrucarol has a longer half-life and a lower clearance, and its liver extraction ratio is about one third of that of T-2 and HT-2 toxins. Therefore, verrucarol is less susceptible to a liver first-pass effect and its partially absorbed after oral administration. These characteristics make verrucarol the first partially absorbed trichothecene whose pharmacokinetics was investigated following oral administration.


Assuntos
Sesquiterpenos/farmacocinética , Tricotecenos/farmacocinética , Administração Oral , Animais , Cromatografia Gasosa , Cães , Estabilidade de Medicamentos , Feminino , Meia-Vida , Injeções Intravenosas , Masculino , Ligação Proteica , Solubilidade , Toxina T-2/farmacocinética
9.
J Ethnopharmacol ; 33(1-2): 187-91, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1943167

RESUMO

Essential oil from Achillea fragrantissima exerted a bactericidic effect on several gram positive and gram negative bacterial strains, as well as on Candida albicans. The oil was fractionated on sillica gel columns by a gradient of ether in petrol ether (30 degrees C-40 degrees C). Two fractions which contained less polar compounds were active against C. albicans only. The fractions which contained more polar compounds inhibited the growth of all the microorganisms tested. One of these compounds was identified as terpinen-4-ol. Commercial terpinen-4-ol had a similar antimicrobial activity.


Assuntos
Anti-Infecciosos/farmacologia , Óleos Voláteis/farmacologia , Plantas Medicinais/química , Antibacterianos , Bactérias/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Cromatografia em Camada Fina , Cromatografia Gasosa-Espectrometria de Massas , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Israel , Testes de Sensibilidade Microbiana , Óleos Voláteis/química
10.
Vet Parasitol ; 206(3-4): 258-66, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25468024

RESUMO

High infectivity of entomopathogenic fungi to ticks under laboratory conditions has been demonstrated in many studies. However, the few reports on their use under field conditions demonstrate large variations in their success, often with no clear explanation. The present study evaluated the factors affecting the efficacy of the fungus Metarhizium brunneum against the tick Rhipicephalus (Boophilus) annulatus. It demonstrates how environmental conditions and ground cover affect the efficiency of the fungus under field conditions. During the summer, 93% of tick females exposed to fungus-contaminated ground died within 1 week, whereas during the winter, only 62.2% died within 6 weeks. Nevertheless, the hatchability of their eggs was only 6.1% during the summer and 0.0% during winter. Covering the ground with grass, leaves or gravel improved fungal performance. Aside from killing female ticks, the fungus had a substantial effect on tick fecundity. Fungal infection reduced the proportion of female ticks laying full-size egg masses by up to 91%, and reduced egg hatchability by up to 100%. To reduce the negative effect of outdoor factors on fungal activity, its conidia were mixed with different oils (olive, canola, mineral or paraffin at 10% v/v) and evaluated in both laboratory and field tests for efficacy. All tested oils without conidia sprayed on the sand did not influence tick survival or weight of the laid eggs but significantly reduced egghatchability. Conidia in water with canola or mineral oil spread on agarose and incubated for 18 h showed 57% and 0% germination, respectively. Comparing, under laboratory conditions, the effects of adding each of the four oils to conidia in water on ticks demonstrated no effect on female mortality or weight of the laid egg mass, but the percentage of hatched eggs was reduced. In outdoor trials, female ticks placed on the ground sprayed with conidia in water yielded an average of 175 larvae per female and there was no hatching of eggs laid by females placed on ground sprayed with conidia in water with canola or mineral oils.


Assuntos
Metarhizium/fisiologia , Controle Biológico de Vetores/métodos , Rhipicephalus/microbiologia , Infestações por Carrapato/prevenção & controle , Animais , Meio Ambiente , Feminino , Larva , Óleo Mineral , Poaceae , Esporos Fúngicos
11.
Biopharm Drug Dispos ; 15(7): 609-16, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7849236

RESUMO

The pharmacokinetics and renal excretion of a trichothecene mycotoxin, verrucarol, were studied in six mongrel dogs following IV administration (0.4 mg kg-1). The fraction of verrucarol excreted intact in the urine ranged from 0.9% to 2.7% of the administered dose. The fraction of verrucarol metabolites excreted in the urine was 32-60% for verrucaryl glucuronides and 32-47% for verrucaryl sulphates. These urinary conjugated metabolites were analysed quantitatively following their enzymatic hydrolysis. The half-life of verrucarol calculated from the urinary data of its conjugated metabolites was not significantly different from the half-life calculated from the plasma data of the parent compound.


Assuntos
Tricotecenos/farmacocinética , Animais , Cães , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Glucuronatos/urina , Meia-Vida , Hidrólise , Masculino , Sulfatos/urina , Tricotecenos/administração & dosagem , Tricotecenos/urina
12.
Hum Reprod ; 12(2): 373-5, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9070728

RESUMO

The concentrations of the enviromental pollutant 2,3,7,8-tetrachlorodibenzo-p-dioxin were measured in the blood of 44 infertile women with endometriosis (study group), and in 35 age-matched women with tubal infertility (control group). Eight women with endometriosis (18%) were dioxin positive as compared to one woman (3%) in the controls (P = 0.04). Although the concentrations of dioxin did not seem to be directly correlated with the severity of endometriosis, these observations contribute to the accumulating data linking dioxin to endometriosis in humans.


Assuntos
Dioxinas/sangue , Endometriose/sangue , Adulto , Biomarcadores , Feminino , Humanos
13.
Mycotoxin Res ; 17 Suppl 2: 198-201, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23605871

RESUMO

Mycotoxins contamination is highly non-uniformly distributed as is well recog-nized by the EC, by not only setting legal limits in a series of commodities, but also schedule a sampling plan that takes this heterogeneity into account. In practice however, it turns out that it is very difficult to carry out this sampling plan in a harmonised way. Applying the sampling plan to a container filled with pallets of bags (i.e. with nuts or coffee beans) varies from very laborious to almost impossible. The presented non-destructive automated method to sample bulk food could help to overcome these practical problems and to enforcing of EC directives. It is derived from a tested and approved technology for detection of illicit substances in security applications. It has capability to collect and iden-tify ultra trace contaminants, i.e. from a fingerprint of chemical substance in a bulk of goods, a cargo pallet load (~ 1000 kg) with boxes and commodities.The technology, patented for explosives detection, uses physical and chemistry processes for excitation and remote rapid enhanced release of contaminant residues, vapours and particulate, of the inner/outer surfaces of inspected bulk and collect them on selective probes. The process is automated, takes only 10 minutes, is non-destructive and the bulk itself remains unharmed. The system design is based on applicable international regulations for shipped cargo hand-ling and transportation by road, sea and air. After this process the pallet can be loaded on a truck, ship or plane. Analysis can be carried out before the cargo leaves the place of shipping. The potent application of this technology for myco-toxins detection, has been demonstrated by preliminary feasibility experiments. Aflatoxins were detected in pistachios and ochratoxin A in green coffee beans bulk. Both commodities were naturally contaminated, priory found and confirm-ed by common methods as used at routine inspections. Once the contaminants are extracted from a bulk shipment, an appropriate existing analytical method, i.e. a CEN method, can be used to measure the mycotoxins.The system, routinely in use for explosives detection, was able to screen bulk food and feed for mycotoxins, through non-destructive automated sampling of a whole batch/lot/sublot of commodities. The opportunity to sample a whole bulk would provide more effective tools for inspection at seaports, production facili-ties and distri-bution points. It will advance the current process of myco-toxins check because: (i) Checks will be automated and harmonized, (ii) Checks will be non-destructive, (iii) Checks will be faster and allow a greater amount of bulk commodities to be inspected and (iv) The ability to check, with automated equipment, larger portions of lots of a shipment will increase the probability to detect the heterogeneous mycotoxins contamination in bulk foods. The poster provides some results of feasibility experiments indicating the capability of this technology for inspection of commodities bulks for the detection of mycotoxins, at legal limits, in naturally contaminated food.

14.
Biopharm Drug Dispos ; 15(1): 45-52, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8161715

RESUMO

The pharmacokinetics of two new sustained-release (SR) products of diltiazem, Dilapress 120 mg tablets and Dilapress 240 mg tablets, was analysed and characterized in three different studies, in comparison to the following diltiazem SR formulations: Cardizem Retard, Cardizem SR, and Cardizem CD. Dilapress 120, designated for twice-daily dosing, was found to be bioequivalent to Cardizem SR and to Cardizem Retard with mean (+/- SD) relative bioavailability values of 99 +/- 27% and 113 +/- 38%, respectively. Dilapress 240, designed for once-a-day treatment, was found to have a slower absorption rate than Cardizem SR and its extent of absorption was 56 +/- 19% relative to that of Cardizem SR. However, the bioavailability of Dilapress 240 relative to that of Cardizem CD was 118 +/- 46%, indicating that the bioavailability of Cardizem CD relative to that of Cardizem SR was only 54 +/- 29%. Diltiazem is partially available due to a saturable liver first-pass effect. A high dose of Cardizem SR may partially escape this first-pass effect and, thus, achieve a higher extent of absorption than a slower SR product. Consequently, SR products of diltiazem designed for once-daily treatment may not reach the saturation stage in the liver first-pass effect process that diltiazem is susceptible to. Consequently, a twice-daily SR product of diltiazem cannot serve as a reference for extent of absorption assessments of a once-daily SR product.


Assuntos
Diltiazem/farmacocinética , Absorção , Análise de Variância , Disponibilidade Biológica , Cromatografia Líquida de Alta Pressão , Preparações de Ação Retardada , Diltiazem/administração & dosagem , Diltiazem/sangue , Esquema de Medicação , Humanos
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