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1.
Braz. arch. biol. technol ; 65: e22200702, 2022. tab, graf
Article in English | LILACS | ID: biblio-1364476

ABSTRACT

Abstract: Boron is one of the most important micronutrients for plants. Plants may suffer from deficiency or with boron toxicity. Boron plays a role in significant physiological and biochemical events in plants such as synthesis of the cell wall, membrane integrity, antioxidation, transport of photosynthesis products to other organs of the plant. The enzyme activities of ascorbate peroxidase (APX), catalase (CAT), glutathione reductase (GR) and superoxide dismutase (SOD) in three different safflower cultivars (Balcı, Dinçer and Remzibey) subjected to different boric acid concentrations (0, 5, 10, 15 mM) were measured spectrophotometrically, and the changes in the expression levels of the genes that encode these enzymes were obtained by quantitative RT-qPCR. When both the spectrophotometric measurements and the mRNA values were evaluated together, both the activity and mRNA values of APX and GR enzymes were found to be the highest in the Dinçer cultivar among the varieties treated with 15 mM boric acid, while the lowest values of these enzymes were determined in the Remzibey cultivar. According to the RT-qPCR results, the lowest SOD and CAT values were determined in Remzibey. The Dinçer cultivar was found to have the highest antioxidant capacity (APX, GR) to cope with oxidative stress caused by boric acid application at high concentrations. The sensitive Remzibey cultivar was found to have the lowest antioxidant capacity to cope with such oxidative stress. Balcı was found to be closer to Dinçer than to Remzibey in terms of boron tolerance. As a result, the boron-sensitive cultivar had low antioxidant activity.


Subject(s)
Trace Elements/administration & dosage , Boron/administration & dosage , Crop Production , Carthamus tinctorius/metabolism , Antioxidants/metabolism , Trace Elements/toxicity , Boron/toxicity , Gene Expression/drug effects , Oxidative Stress/drug effects , Carthamus tinctorius/enzymology , Carthamus tinctorius/genetics
2.
Iranian Journal of Basic Medical Sciences. 2008; 10 (4): 222-228
in English | IMEMR | ID: emr-99454

ABSTRACT

High concentration of iron and other trace elements could restrict bacterial growth and modify their metabolic pattern as well. However, this study aimed to find out the influence of iron, chromium, cadmium and synergism or antagonism between these elements on the growth of a gram positive bacterium. In a series of experiments, Bucillus cereus was cultured in a nutrient broth which supplemented with Fe[+2], Fe[+3], Cr[+3], Cd[+2] separately, or in combination with each other, at 37°C for 5 hours. Bacterial growth was measured every half - hour, using spectrophotometer. The results indicated that bacterial growth rate reduced in the presence of 0.5 mM/L concentration of Fe[+2] or Fe[+3], in comparison with control and the growth of bacteria was inhibited by 1 mM/L concentration of iron. The results also revealed that Fe [III] as well as Fe [II] was toxic for bacteria. Chromium had partial inhibitory effects on the growth of bacteria and cadmium was very toxic. Cr[+3] and Cd[+] had antagonistic effect with iron on the growth of bacteria. Data obtained here provide a potentially interesting conceptual advance in toxic effects of trace elements on pathogenic bacteria


Subject(s)
Trace Elements/toxicity , Iron/toxicity , Cadmium/toxicity , Chromium/toxicity , Bacillus cereus/drug effects
3.
Vet. Méx ; 28(2): 83-6, abr.-jun. 1997. tab
Article in Spanish | LILACS | ID: lil-227530

ABSTRACT

Para realizar la presente investigación se contó con 20 muestras de un producto para perros hecho a base de esquilmos de curtiduría llamdo "carnaza". Estas muestras de varias fuentes comerciales del Valle de México, fueron remitidas al Laboratorio de toxicología de la Facultad de Medicina Veterinaria y Zootencia de la Universidad Nacional Autónoma de México, porque se asociaban con la muerte de los perros. Estas carnazas en forma de hueso son expendidas al público para que los perros jueguen y se limpien los dientes al mordisquearlas, pero la mayoría son consumidas. El análisis para elementos tóxicos y esenciales se practicó por espectrometría de absorción atómica para Cr, Pb, Cd, Ti, Ni, Fe, Cu y Zn. La preparación de la muestra se llevó a cabo por digestión alcalina y ácida. A cada digerido de la misma muestra se le leyó el contenido de estos minerales y después se sumarón ambos para notificarlo como totales. El promedio de los elementos minerales tóxicos encontrados en las muestras están por encima de la norma oficial mexicana (a ppm) para los alimentos de animales el contenido encontrado fue: Cr, 104; Pb, 25; Cd, 16; Ti, 4378 y Ni, 7.9 ppm. De los esenciales, la concentración de Fe es de 1128 que es 10 veces mayor de la que el perro necesita para nutrirse, pero el Cu y Zn son deficientes. También se concluye que la extracción alcalina digiere el cuero fácilmente, pero no solubiliza los elementos minerales tanto como la digestión ácida. Aunque la correlación entre el contenido mineral de cada muestra por los dos sistemas de digestión no es alta, se tiene cierta similitud para el Cr, Pb, Ti y Fe. El contenido de los metales tóxico, especialmente el Titanio, aunque se considera inerte con esta concentraciones (4378 ppm) debe señalarse como riesgo, pues se incluye en la cadena alimenticia


Subject(s)
Animals , Dogs , Poisoning/etiology , Solubility , Trace Elements/analysis , Trace Elements/toxicity , Dog Diseases/etiology , Dog Diseases/mortality
4.
Medical Journal of the Islamic Republic of Iran. 1992; 6 (2): 139-142
in English | IMEMR | ID: emr-24860

ABSTRACT

Toxic effects of trace elements upon the hypothalamic- pituitary- testicular axis and sex hormones have been reported in recent years. It is generally considered that CdCl2 poisoning causes histopathological changes in the testicles of male rats. Little attention had been drawn to the possible toxic effects of CdCl2 on the ovary and female sex hormones. The purpose of the present study was to determine the subacute poisoning effects of CdCI2 [10 mg/kg I.P. for 15 days] on the female gonadotropins and sex hormones such as FSH, LH, progestrone, estradiol and prolactin. Female wistar rats 12 weeks of age [approximately 300g] were divided into two groups [10 in each group], one group received CdCl2 and the other received saline as a control. Serum hormones were measured by radioimmunoassay. In contrast to male animals, CdCl2 injection did not affect serum FSH and LH concentration in female rats, whereas serum prolactin concentration was significantly elevated compared with that of control animals [p<0.05] after CdCl2 injection. This effect is not similar to the effect of CdCl2 on the prolactin of male rats which was reported by Chandler and coworkers. No marked differences were observed between the control and experimental values of serum estradiol and progestrone concentrations


Subject(s)
Gonadal Steroid Hormones/biosynthesis , Trace Elements/toxicity , Follicle Stimulating Hormone/blood , Luteinizing Hormone/blood
5.
Rev. Asoc. Méd. Argent ; 104(9/12): 6-8, 1991.
Article in Spanish | LILACS | ID: lil-175442

ABSTRACT

Se clasifican los elementos químicos en nutrientes (macro y micro, esenciales y beneficiosos), tóxicos y contaminantes, con ejemplos. Se especifican los tipos de toxicidad que pueden producir algunos oligoelementos, geno, terato y neurotoxicidad incluyendo en esta última la toxicidad conductual. Se discute la conveniencia de conocer la carga corporal real de oligoelementos y los medios para hacerlo. Se discuten los datos que pueden obtenerse con su determinación en sangre, orina y cabellos y la ventaja de estos últimos como índice de la carga corporal. Se discuten las vías de ingreso de estos elementos al organismo usando como ejemplo el plomo, sus posibles efectos tóxicos y el mecanismo de tales efectos. Se ejemplifica su importancia con ejemplos para cuatro especialidades clínicas: a) psiquiatría, usando las depresiones como modelo, sus posibles etiologías por excesos o carencias de oligoelementos. b) reproducción, con ejemplos causales de esterilidad. c) pediatría, ejemplificando con los oligoelementos tóxicos. c) dermatología con ejemplos de afecciones por elementos tóxicos. Se destaca la creciente importancia de estos elementos y la necesidad de incrementar su determinación especialmente en cabellos como índice del status corporal.


Subject(s)
Humans , Male , Female , Adult , Trace Elements/classification , Anorexia , Depression/metabolism , Elements/analysis , Elements/deficiency , Hyperkinesis , Infertility , Intellectual Disability , Trace Elements/analysis , Trace Elements/toxicity
6.
In. Waitzberg, Dan Linetzky. Nutricao enteral e parenteral na pratica clinica. s.l, Atheneu, 1990. p.52-74, tab. (Enfermagem. Nutricao).
Monography in Portuguese | LILACS | ID: lil-108251
7.
Indian J Ophthalmol ; 1987 ; 35(5-6): 311-4
Article in English | IMSEAR | ID: sea-70080

ABSTRACT

Acute toxicity of lead, nickel and cobalt on rabbit retina was studied. It was found that all these metals produced similar photoreceptor degenerative changes, but lead produced extensive degenerative changes at ganglion cell layer also. Electroretinographically nickel group showed statistically (by analysis of variance) significant prolongation of 'b' wave implicit time as seen in autosomal dominant retinitis pigmentosa.


Subject(s)
Animals , Cobalt/toxicity , Lead/toxicity , Nickel/toxicity , Rabbits , Retina/drug effects , Trace Elements/toxicity
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