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1.
Poult Sci ; 93(9): 2304-13, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24974390

RESUMO

Radiation from UV-C has been demonstrated as a potential surface decontamination method in addition to several advantages over regular sanitation methods. However, UV-C radiation possibly affects the physicochemical properties of meat products. To determine the optimum exposure time for bacterial reduction, 39 chicken breasts, inoculated with a pool of Salmonella spp., were submitted to 3 levels of UV-C intensities (0.62, 1.13, and 1.95 mW/cm²) for up to 120 s. After the optimum exposure time of 90 s was determined, changes in the biogenic amines, total aerobic mesophilic bacteria, Enterobacteriaceae, lipid oxidation, pH, and instrumental color were evaluated in 84 chicken breasts that were irradiated (0.62, 1.13, and 1.95 mW/cm²) and stored at 4°C for 9 d. The groups treated with UV-C radiation exhibited an increase in tyramine, cadaverine, and putrescine contents (P < 0.05). The highest UV-C intensity (1.95 mW/cm²) promoted a decrease in the initial bacterial load, and extended the lag phase and the shelf life. The groups irradiated with 1.13 and 1.95 mW/cm² exhibited a more stable b* value than the other groups; similar trends for L*, a*, pH, and TBA reactive substance values were observed among all groups. The UV-C light was demonstrated to be an efficient alternative technology to improve the bacteriological quality of chicken meat without negatively affecting the physical and chemical parameters of chicken breast meat. Nonetheless, the increases on the biogenic amines content should be considered as an effect of the UV processing and not as an indicator of bacterial growth.


Assuntos
Bactérias/efeitos da radiação , Aminas Biogênicas/efeitos da radiação , Microbiologia de Alimentos/métodos , Conservação de Alimentos/métodos , Carne/efeitos da radiação , Carne/normas , Raios Ultravioleta , Animais , Bactérias/crescimento & desenvolvimento , Aminas Biogênicas/análise , Aminas Biogênicas/química , Galinhas , Temperatura Baixa , Contagem de Colônia Microbiana , Concentração de Íons de Hidrogênio/efeitos da radiação , Metabolismo dos Lipídeos/efeitos da radiação , Carne/análise , Carne/microbiologia , Oxirredução/efeitos da radiação , Músculos Peitorais/microbiologia , Músculos Peitorais/fisiologia , Músculos Peitorais/efeitos da radiação , Salmonella/crescimento & desenvolvimento , Salmonella/efeitos da radiação , Fatores de Tempo
2.
Life Sci ; 73(24): 3073-82, 2003 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-14550848

RESUMO

The aim of this study was to determine whether exposure to magnetic fields might affect human health and to look for possible effects of acute exposure (9 hours) to 50-Hz magnetic fields (10 microT) on the urinary concentration of biogenic amines. Thirty-two young men (20-30 years old) were divided into two groups (sham-exposed and exposed group) of 12 to 16 subjects each. All subjects participated in two 24-hour experiments to evaluate the effects of both continuous and intermittent exposure to magnetic fields. The subjects were exposed to the magnetic field from 2300 to 0800, while lying down. Total urine (from 2300 to 0800) was collected at 0800. The results (expressed as a ratio of biogenic amine excretion to creatinine excretion (nmol/mmol)) did not differ significantly between sham-exposed and exposed men for any of the parameters measured: adrenaline, noradrenaline, dopamine, dihydroxyphenylalanine, 3,4-dihydroxyphenylacetic acid, homovanillic acid and 5-hydroxyindoleacetic acid. These results suggest that nocturnal exposure to either continuous or intermittent 50-Hz magnetic fields of 10 microT does not affect, at least under our experimental conditions, the nocturnal excretion of biogenic amines in healthy young men.


Assuntos
Aminas Biogênicas/urina , Ritmo Circadiano , Campos Eletromagnéticos/efeitos adversos , Exposição Ambiental/efeitos adversos , Adulto , Aminas Biogênicas/efeitos da radiação , Humanos , Masculino , Decúbito Dorsal
3.
Klin Khir ; (8): 42-4, 2000 Aug.
Artigo em Russo | MEDLINE | ID: mdl-11036314

RESUMO

The dynamics of the biogenic amines level in the blood of patients after performance of hemorrhoidectomy was dependent on severity of an organism stress-reaction predicting the wound healing outcome. When the wound irradiation using the low-energy laser of infrared diapason is performed in patients with the lowered reactivity of organism the histamine and serotonin contents dynamics is the same as in the patients with normal reactivity.


Assuntos
Aminas Biogênicas/sangue , Aminas Biogênicas/efeitos da radiação , Raios Infravermelhos , Terapia a Laser/métodos , Adulto , Feminino , Humanos , Masculino , Fatores de Tempo , Cicatrização
4.
Neurotoxicol Teratol ; 22(4): 593-602, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10974598

RESUMO

The present investigation was carried out to study the effects of in utero exposure to low-level gamma radiation (0.25, 0.35, or 0.50 Gy) on the postnatal neurophysiology and neurochemistry of the mouse. Pregnant Swiss albino mice were irradiated on days 11.5, 12.5, 14.5, or 17.5 post coitus (PC) and allowed to deliver. Locomotor and exploratory activities, learning and memory functions, and emotional activities were tested at 3 months of age using behavior tests. A representative group of animals was killed and hippocampal biogenic amines, noradrenaline, dopamine, serotonin (5-HT), and 5-HT's metabolite 5-hydroxy indoleactetic acid (5-HIAA), were measured. Exposure to 0.25 Gy at any of the gestation days did not produce any significant impairment in brain functions. However, an increase in gamma irradiation to 0.50 Gy on all the gestation days produced significant impairment in locomotor (open-field test) and anxiolytic (light and dark area test) activities, learning (hole board test), memory functions (active avoidance test), and emotional activity (rearings). The late fetal period is relatively resistant to radiation-induced impairment of brain functions. Both of the organogenesis gestation days showed a higher sensitivity than the fetal gestation days studied. Even a lower dose of 0.35 Gy when exposed on the late organogenesis days 11.5 and 12.5 PC, produced significant reduction in locomotor and exploratory activities. Day 11.5 PC showed a higher sensitivity than the other PC days studied. Biogenic amines did not show significant change after any of the exposures on any of the gestation days. The results suggest a threshold between 0.25 to 0.35 Gy for postnatal neurobehavior changes.


Assuntos
Comportamento Animal/efeitos da radiação , Efeitos Tardios da Exposição Pré-Natal , Animais , Aprendizagem da Esquiva/efeitos dos fármacos , Aminas Biogênicas/efeitos da radiação , Condicionamento Psicológico/efeitos dos fármacos , Relação Dose-Resposta à Radiação , Comportamento Exploratório/efeitos da radiação , Feminino , Raios gama , Idade Gestacional , Masculino , Memória/efeitos dos fármacos , Camundongos , Atividade Motora/efeitos da radiação , Gravidez
5.
Radiats Biol Radioecol ; 37(3): 372-6, 1997.
Artigo em Russo | MEDLINE | ID: mdl-9244525

RESUMO

Sublethal doses of X radiation (0.5 Gy and 1 Gy) caused the alterations in levels of main components of endogenous radioresistance background in rat tissues. There were demonstrated the decrease of serotonin content in stomach mucosa and spleen, adrenalin, noradrenalin and corticosteroid contents in adrenal glands, nonprotein thiols content in spleen, and the increase of lipid peroxide level in serum on the 3-14 days after irradiation. The recovery of the investigated parameters was occurred to the 21 day after exposure.


Assuntos
Tolerância a Radiação , Corticosteroides/metabolismo , Corticosteroides/efeitos da radiação , Animais , Aminas Biogênicas/metabolismo , Aminas Biogênicas/efeitos da radiação , Relação Dose-Resposta à Radiação , Peróxidos Lipídicos/metabolismo , Peróxidos Lipídicos/efeitos da radiação , Masculino , Tolerância a Radiação/fisiologia , Ratos , Compostos de Sulfidrila/metabolismo , Compostos de Sulfidrila/efeitos da radiação , Fatores de Tempo
7.
Vrach Delo ; (1): 24-7, 1991 Jan.
Artigo em Russo | MEDLINE | ID: mdl-2011885

RESUMO

A study is presented of the effect of copper vapors laser therapy on the content of biogenic amines--serotonin and histamine and the state of adenylcyclase (AC) system (content of cAMP, cGMP and AC activity) at the edge of the gastric ulcer. Direct effect of laser radiation (single dose 10--15 J.) produced a significant increase of serotonin, histamine, cAMP, AC activity and an insignificant increase of cGMP. Healing of the ulcerative defect after 5--6 laser therapy sessions was followed by a reduction of the content of serotonin, increase of histamine, cAMP and AC activity. The authors discuss the biostimulating effect of laser radiation by influencing the inflammatory-proliferative processes in the epitheliocytes in prolonged nonhealing gastric ulcers.


Assuntos
Aminas Biogênicas/efeitos da radiação , Terapia a Laser , Nucleotídeos Cíclicos/efeitos da radiação , Úlcera Gástrica/radioterapia , Cicatrização/efeitos da radiação , Adulto , Aminas Biogênicas/metabolismo , Terapia Combinada , Feminino , Mucosa Gástrica/metabolismo , Mucosa Gástrica/efeitos da radiação , Humanos , Masculino , Pessoa de Meia-Idade , Nucleotídeos Cíclicos/metabolismo , Dosagem Radioterapêutica , Úlcera Gástrica/metabolismo
8.
Radiobiologiia ; 30(2): 252-5, 1990.
Artigo em Russo | MEDLINE | ID: mdl-2190263

RESUMO

In experiments with albino male rats subjected to whole-body pulse electromagnetic irradiation of 100 mTl magnetic induction, the luminescent histochemical methods and the subsequent microspectrofluorometry were used to determine the content of biogenic amines (catecholamines, serotonin, and histamine) in spinal ganglia neurons. Significant changes were revealed not only in the content of all studied bioamines but in the histamine/serotonin ratio as well.


Assuntos
Aminas Biogênicas/efeitos da radiação , Campos Eletromagnéticos , Fenômenos Eletromagnéticos , Gânglios Espinais/efeitos da radiação , Irradiação Corporal Total , Animais , Aminas Biogênicas/metabolismo , Catecolaminas/análise , Catecolaminas/efeitos da radiação , Gânglios Espinais/metabolismo , Histamina/análise , Histamina/efeitos da radiação , Histocitoquímica , Masculino , Microscopia de Fluorescência , Ratos , Serotonina/análise , Serotonina/efeitos da radiação , Espectrometria de Fluorescência , Fatores de Tempo
10.
J Pharmacol Methods ; 17(1): 1-14, 1987 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3560982

RESUMO

We describe a simple and sensitive method for the rapid and simultaneous quantification of dopamine, 3-methoxytyramine, 3,4-dihydroxyphenylacetic acid, homovanillic acid, serotonin, 5-hydroxyindoleacetic acid, and 5-hydroxytryptophan in the picogram range in small samples of brain tissue. After minimal sample preparation the amines were analyzed utilizing isocratic separation and reversed-phase high-performance liquid chromatography with amperometric detection. The effects of pH and methanol concentration in the solvent on the retention times of the amines on two different C-18 columns were investigated. Stabilities of the amines in solution were determined under various conditions. Light and air were found to be detrimental to the stability of indoles. In the absence of light, their stability was dependent on temperature and the presence of air; however, in the absence of air, light and/or temperature had little effect. The catechols were stable under most of these conditions. The assay has been applied to study the postmortem stability of dopamine, serotonin, and their metabolites in the striatum of rat brain. In the striatum 4 hr after death, the content of dopamine and 3,4-dihydroxyphenylacetic acid decreased by less than 20%, and 3-methoxytyramine increased by 158%, with no changes in serotonin, 5-hydroxyindoleacetic acid, and homovanillic acid.


Assuntos
Aminas Biogênicas/análise , Animais , Aminas Biogênicas/isolamento & purificação , Aminas Biogênicas/efeitos da radiação , Biotransformação , Química Encefálica , Cromatografia Líquida de Alta Pressão , Estabilidade de Medicamentos , Eletroquímica , Concentração de Íons de Hidrogênio , Luz , Masculino , Metanol , Mudanças Depois da Morte , Ratos , Solventes , Temperatura
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