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1.
Sci Total Environ ; 858(Pt 1): 159664, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36306832

RESUMO

The rewetting of degraded peatlands has been adopted as a method to address climate change. Concerns have been raised about the effects of peat inundation and drying cycles, in more extreme climate events, on the potential release of nitrogen (N) species, in particular ammonium (NH4-N), once rewetted, as well as the physico-chemical and biological properties of the peat. This study used intact peat cores to measure the impact of two different cycles of peat inundation and drying (1 month and 2 month) over a total study duration of 56 weeks on the (1) NH4-N, nitrate-N (NO3-N) and dissolved reactive phosphorus (DRP) in the soil pore water; (2) microbial community structure; (3) physico-chemical properties of the peat; and (4) the structure of the peat, and therefore its ability to mitigate flood risks and storm surges. The study found that rewetted cores released NO3-N in the pore water up to a concentration of 6.25 mg L-1, but had no appreciable impact on NH4-N, which remained below 1.7 mg L-1 over the study duration. DRP moved quickly though the upper layers of the cores, but physico-chemical analysis suggested it was adsorbed to more iron-rich soil, which was present at depths below 0.4 m in the cores. Time intervals between inundation produced no significant difference on the forms of inorganic N released, nor did it compact the soil or change the microbial community structure. The depth of the water table, however, had a significant impact on inorganic N release, particularly NO3-N, which indicates that this N species, and not NH4-N, may be problematic in rewetted peatlands.


Assuntos
Nitrogênio , Solo , Solo/química , Nitrogênio/análise , Fósforo/análise , Nitratos/análise , Água/química
2.
J Prev Alzheimers Dis ; 8(1): 29-32, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33336221

RESUMO

Emerging evidence of brain injury on risk of neurodegenerative diseases such as Alzheimer's disease (AD) and chronic traumatic encephalopathy (CTE) have resulted in interest in therapeutic potential of omega-3 fatty acids (n-3FA). We conducted a systematic review of n-3FA therapeutic efficacy for ageing adults at risk of AD/CTE following a history of repeated head trauma. Databases for articles between 1980-June 2020 were examined for studies reporting on n-3 FAs in adults (≥ 45 years) with a history of repeated brain injury. Following an initial screen of 175 articles, 12 studies were considered but were eventually rejected, as they did not meet inclusion criteria. Our review could find no evidence to support, or disprove, effectiveness of n-3FA intervention in older adults with a history of head trauma. With animal studies showing neuro-restorative potential of n-3FA following brain injury, this review highlights the urgent need for human research in this area.


Assuntos
Doença de Alzheimer/prevenção & controle , Encefalopatia Traumática Crônica/prevenção & controle , Ácidos Graxos Ômega-3/uso terapêutico , Envelhecimento , Doença de Alzheimer/etiologia , Animais , Concussão Encefálica/complicações , Encefalopatia Traumática Crônica/etiologia , Humanos , Recidiva
3.
J Neurol Neurosurg Psychiatry ; 85(2): 227-9, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24039028

RESUMO

OBJECTIVE: To investigate potential abnormalities in subcortical brain structures in conversion disorder (CD) compared with controls using a region of interest (ROI) approach. METHODS: Fourteen patients with motor CD were compared with 31 healthy controls using high-resolution MRI scans with an ROI approach focusing on the basal ganglia, thalamus and amygdala. Brain volumes were measured using Freesurfer, a validated segmentation algorithm. RESULTS: Significantly smaller left thalamic volumes were found in patients compared with controls when corrected for intracranial volume. These reductions did not vary with handedness, laterality, duration or severity of symptoms. CONCLUSIONS: These differences may reflect a primary disease process in this area or be secondary effects of the disorder, for example, resulting from limb disuse. Larger, longitudinal structural imaging studies will be required to confirm the findings and explore whether they are primary or secondary to CD.


Assuntos
Transtorno Conversivo/patologia , Neuroimagem , Tálamo/patologia , Adulto , Tonsila do Cerebelo/patologia , Atrofia/patologia , Gânglios da Base/patologia , Estudos de Casos e Controles , Feminino , Humanos , Masculino
4.
J Pharm Belg ; 53(2): 87-93; discussion 93-5, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9609969

RESUMO

Cisplatin [cis-dichlorodiammineplatinum (II)] is a widely used chemotherapeutic drug that is toxic to the kidney. Concurrent administration of cysteine together with vitamin E, Crocus sativus and Nigella sativa reduced the toxicity of cisplatin in rats. When administered i.p. for 5 alternate days with 3 mg/kg cisplatin, cysteine (20 mg/kg) together with vitamin E (2 mg/rat) an extract of Crocus sativus stigmas (50 mg/kg) and Nigella sativa seed (50 mg/kg) significantly reduced blood urea nitrogen (BUN) and serum creatinine levels as well as cisplatin-induced serum total lipids increases. In contrast, the protective agents given together with cisplatin led to an even greater decrease in blood glucose than that seen with cisplatin alone. The serum activities of alkaline phosphatase, lactate dehydrogenase, malate dehydrogenase, aspartate aminotransferase and alanine aminotransferase of cisplatin-treated rats were significantly decreased, whereas the activities of glutathione reductase and isocitrate dehydrogenase were significantly increased. Addition of cysteine and vitamin E, Crocus sativus and Nigella sativa in combination with cisplatin partially prevented many changes in the activities of serum enzymes. In cisplatin-treated rats, the liver activities of isocitrate dehydrogenase and aspartate aminotransferase were significantly increased, whereas much greater changes were found in the kidneys, with increased activity of glucose-6-phosphate dehydrogenase and decreased activities of alkaline phosphatase, isocitrate dehydrogenase, malate dehydrogenase, aspartate aminotransferase, alanine aminotransferase, sorbitol dehydrogenase and gamma-glutamyl transferase, as well as a decreased phosphorylation to oxidation ratio in the mitochondria, indicating reduced adenosine triphosphate production. Also, administration of cysteine and vitamin E, Crocus sativus and Nigella sativa together with cisplatin partially reversed many of the kidney enzymes changes induced by cisplatin. Cysteine together with vitamin E, Crocus sativus and Nigella sativa tended to protect from cisplatin-induced falls in leucocyte counts, haemoglobin levels and mean osmotic fragility of erythrocytes and also prevented the increase in haematocrit. The results of this study indicate a basis for the toxic effects of cisplatin, and suggest a possible way of counteracting the toxicity by introducing protective agents such sulphydryl compounds, other antioxidants and extracts of natural products. It also appears that cells adapt to the effects of cisplatin through the induction of systems that produce NADPH, which in turn compensates the decrease of free sulphydryl groups. We conclude that cysteine and vitamin E, Crocus sativus and Nigella Sativa may be a promising compound for reducing cisplatin-toxic side effects including nephrotoxicity.


Assuntos
Antineoplásicos/antagonistas & inibidores , Antineoplásicos/toxicidade , Cisplatino/antagonistas & inibidores , Cisplatino/toxicidade , Cisteína/farmacologia , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Vitamina E/farmacologia , Animais , Masculino , Ratos
5.
J Pharm Belg ; 52(4): 149-56, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9316341

RESUMO

Gentamicin, a nephrotoxic aminoglycoside antibiotic, was injected into adult male albino rats, alone or together with methimazole and fish oil. The effects on renal and liver functions and renal thiol status were studied. Gentamicin was administered as two i.p. injections (40 mg/kg body weight) for 3, 7 and 10 consecutive days. The animals were sacrificed 12 hours after the last injection. In gentamicin-treated rats, for 7 and 10 days, blood urea nitrogen (BUN) and serum creatinine concentrations and urinary N-acetyl-beta-D-glucosaminidase (NAG) activity were significantly increased compared with saline-treated controls. Administration of methimazole (20 mg/kg) and fish oil (5 ml/kg) together with gentamicin partially protected against the nephrotoxicity induced by gentamicin by returning the urea and creatinine concentrations and urinary NAG activity to normal levels, despite having higher kidney gentamicin concentrations, especially with methimazole. Rats given gentamicin alone for 3 days exhibited no elevation of BNU, serum creatinine and urinary NAG values. However, these rats exhibited an increase in nonprotein disulfide concentrations and a decrease in renal protein thiol and protein disulfide concentrations, as opposed to rats given gentamicin and methimazole and rats given gentamicin and fish oil. These results show that methimazole and fish oil were effective antagonists of gentamicin-induced nephrotoxicity. Methimazole did not inhibit gentamicin renal uptake but may protect against gentamicin-induced nephrotoxicity by acting as an antioxidant within the kidneys. On the other hand, fish oil may protect against gentamicin-induced nephrotoxicity by counteracting the biochemical alterations induced by the drug in the renal cortex. We conclude that methimazole and fish oil may be compounds for reducing gentamicin-toxic side effects, including nephrotoxicity, without compromising its antibiotic activity.


Assuntos
Óleos de Peixe/uso terapêutico , Gentamicinas/antagonistas & inibidores , Gentamicinas/toxicidade , Antagonistas de Hormônios/uso terapêutico , Nefropatias/prevenção & controle , Metimazol/uso terapêutico , Animais , Gentamicinas/farmacocinética , Rim/metabolismo , Nefropatias/induzido quimicamente , Masculino , Ratos
6.
Life Sci ; 59(22): 1881-90, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8950285

RESUMO

The effects of acute and chronic treatment with morphine and stadol on the functional activity of the hypothalamo-pituitary-adrenocortical (HPA) system in the rat were studied by investigating their effects on the secretion of adrenocorticotrophin (ACTH) by the pituitary gland and corticotrophin-releasing hormone (CRH) by the hypothalamus. The acute injection of morphine or stadol (3.5 mg/100 g body weight i.p.) caused a rise at 5 and 25 min followed by a fall at 90 and 120 min in the concentrations of ACTH in the plasma and adenohypophysis and in hypothalamic CRH content. It appears that, in the rat, the response of HPA system to acute morphine or stadol administration could change depending upon the time of courses. In addition, chronic morphine or stadol (0.5 mg/100 g body weight i.p. daily) administration for a period of 7 days have little effect on plasma and adenohypophysis ACTH concentrations and hypothalamic CRH content. This may indicate that drug tolerance might have developed. Conversely, repeated daily doses of morphine or stadol (2 mg/ 100 g body weight i.p.) for 7 days cause a significant lowering of plasma and pituitary ACTH concentrations and hypothalamic CRH content. These data suggest that the effect of both drugs is dose related. Overall, the present results are consistent with an increased release of pro-opiomelanocortin-derived peptides after acute morphine or stadol treatment for a short-term, and with a decreased release of these peptides in chronic treatment. However, the results indicate that morphine and stadol change HPA activity by acting on specific receptors in the hypothalamus and raise the possibility that opioid peptides and their receptors are physiologically important in the control of the secretion of CRH.


Assuntos
Córtex Suprarrenal/efeitos dos fármacos , Hormônio Adrenocorticotrópico/metabolismo , Butorfanol/farmacologia , Hormônio Liberador da Corticotropina/metabolismo , Hipotálamo/efeitos dos fármacos , Morfina/farmacologia , Córtex Suprarrenal/metabolismo , Hormônio Adrenocorticotrópico/sangue , Animais , Hormônio Liberador da Corticotropina/sangue , Hipotálamo/metabolismo , Masculino , Hipófise/efeitos dos fármacos , Ratos
7.
Lancet ; 342(8881): 1197-200, 1993 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-7901528

RESUMO

Many neuropsychiatric disorders differ between the sexes in incidence, symptoms, and age at onset. To investigate the effects of X-chromosome aneuploidy and of sex steroid deficiency during childhood on brain structure and function, we used neuropsychological tests and quantitative magnetic resonance imaging (MRI) to study the brains of eighteen women with Turner's syndrome (TS) and nineteen healthy control women of similar age. Nine TS subjects had mosaic 45,X karyotypes, and 9 had non-mosaic 45,X. The TS group had significantly lower scores than the controls for all the Wechsler adult intelligence scale tests, except verbal comprehension and reading level. The greatest difference was in visuospatial construction (mean 90 [SD12] vs 118 [13], p < 0.0001). The TS subjects also had a greater discrepancy than controls between verbal and performance intelligence quotients (9 [8] vs -5 [9], p < 0.001). We found that TS subjects had significantly smaller values than controls in MRI-measured volumes of hippocampus, caudate, lenticular, and thalamic nuclei, and parieto-occipital brain matter, on both sides. Women with mosaic TS had values between the full TS and control groups for cerebral hemisphere and lenticular and thalamic nuclei volume and for verbal ability. Within the mosaic TS group, visuospatial ability was significantly correlated with the percentage of lymphocytes that had the 45,X karyotype. Hippocampal volume and memory test scores were significantly lower in mosaic and non-mosaic 45,X TS subjects than in controls. We postulate that in human beings the X chromosome plays an important part in the development and ageing of grey matter in striatum, diencephalon, and cerebral hemispheres.


Assuntos
Aneuploidia , Encéfalo/patologia , Síndrome de Turner/genética , Cromossomo X , Adulto , Córtex Cerebral/patologia , Estrogênios/administração & dosagem , Feminino , Hormônios Esteroides Gonadais/deficiência , Hipocampo/patologia , Humanos , Testes de Inteligência , Imageamento por Ressonância Magnética , Testes Neuropsicológicos , Progestinas/administração & dosagem , Tálamo/patologia , Hormônios Tireóideos/administração & dosagem , Síndrome de Turner/patologia , Síndrome de Turner/psicologia
8.
Br J Med Psychol ; 60 ( Pt 1): 85-8, 1987 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3552026

RESUMO

After fantasy work in a trance state a patient with post-traumatic headaches experienced some relief as other symptoms appeared, and then total relief along with the disappearance of the other symptoms. He was able to withdraw from all medications.


Assuntos
Terapia Comportamental , Cefaleia/terapia , Transtornos de Estresse Pós-Traumáticos/terapia , Fantasia , Humanos , Hipnose , Masculino , Pessoa de Meia-Idade , Terapia de Relaxamento
9.
Biofeedback Self Regul ; 8(1): 135-52, 1983 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6882811

RESUMO

The efficacy of progressive relaxation, fingertip temperature training, and EMG training of the frontalis muscles was tested against chronic migraine and tension headaches in a double-blinded 3 X 2 design. All 56 subjects reported being conditioned in the course of the nine 1/2-hour training sessions. Detailed records of perceived severity and duration of the headaches were maintained by the subjects before the study and for at least 3 months after the training period. While even a conservative F revealed a diminution of perceived severity, of hours/month of headache, and of an index conceived by Budzynski, Stoyva, Adler, and Mullaney (1973), across time, at beyond the .05 level of significance, no specific treatment emerged as clearly most effective for either type of headache. Over time, however, progressive relaxation was not as good as the other procedures in reducing the number of hours/month of headache.


Assuntos
Biorretroalimentação Psicológica , Cefaleia/terapia , Transtornos de Enxaqueca/terapia , Adolescente , Adulto , Método Duplo-Cego , Eletromiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Relaxamento Muscular , Avaliação de Processos e Resultados em Cuidados de Saúde , Temperatura Cutânea
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