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101.
Pelin Aribal Kocatürk M. Cenk Akbostanci Canan Işikay Aylin Öcal Deniz Tuncel Güzin Özelçi Kavas Nermin Mutluer 《Biological trace element research》2001,80(2):115-124
Ischemia is associated with the pathological changes caused by the accumulation of reactive oxygen metabolites (ROM) in cerebrovascular
accident (CVA). The aim of this study was to determine red cell copper/zinc-superoxide dismutase (Cu/Zn-SOD) and catalase
activities and copper and zinc concentrations both in plasma and in red cells in CVA. Cu/Zn-SOD and catalase activities of
16 patients, with an average age of 64 yr, were measured spectrophotometrically; copper and zinc concentrations were determined
by atomic absorption spectrophotometer. The results showed that Cu/Zn-SOD activity was increased markedly in patients compared
to the young controls and reached a peak on the d 5 of the disease, whereas the catalase activity of the patients on d 3 and
d 5 were in the normal range, but higher on d 10. The enzyme activities of the elderly group were generally increased compared
to the young controls. Copper and zinc concentrations showed corresponding alterations. These findings suggested that the
effects of oxidative stress in CVA might be reflected in red cell and plasma parameters.
Presented at the III International Congress of Pathophysiology, Lahti, Finland, 28 June–3 July, 1998. 相似文献
102.
Arzu Karakurt Meral Özalp Şamil Işık James P. Stables Sevim Dalkara 《Bioorganic & medicinal chemistry》2010,18(8):2902-2911
In this study, as a continuation of our research for new (arylalkyl)imidazole anticonvulsant compounds, the design, synthesis and anticonvulsant/antimicrobial activity evaluation of a series of 2-acetylnaphthalene derivatives have been described. Molecular design of the compounds has been based on the modification of nafimidone [1-(2-naphthyl)-2-(imidazol-1-yl)ethanone], which is a representative of the (arylalkyl)imidazole anticonvulsant compounds as well as its active metabolite, nafimidone alcohol (3, 4). In general, these compounds were variously substituted at the alkyl chain between naphthalene and imidazole rings and subjected to some other modifications to evaluate additional structure–activity relationships. The anticonvulsant activity profile of those compounds was determined by maximal electroshock seizure (MES) and subcutaneous metrazol (scM) seizure tests, whereas their neurotoxicity was examined using rotarod test. All the ester derivatives of nafimidone alcohol (5a–h), which were designed as prodrugs, showed anticonvulsant activity against MES-induced seizure model. Four of the most active compounds were chosen for further anticonvulsant evaluations. Quantification of anticonvulsant protection was calculated via the ip route (ED50 and TD50) for the most active candidate (5d). Observed protection in the MES model was 38.46 mg kg?1 and 123.83 mg kg?1 in mice and 20.44 mg kg?1, 56.36 mg kg?1 in rats, respectively. Most of the compounds with imidazole ring also showed antibacterial and/or antifungal activities to a certain extent in addition to their anticonvulsant activity. 相似文献
103.
Hypolimnetic phosphorus and nitrogen dynamics in a small,eutrophic lake with a seasonally anoxic hypolimnion 总被引:4,自引:0,他引:4
In situ estimates of sediment nutrient flux are necessary to understand seasonal variations in internal loading in lakes.
We investigated the sources and sinks of nutrients in the hypolimnion of a small (0.33 km2), relatively shallow (18 m max. depth), eutrophic lake (Lake Okaro, New Zealand) in order to determine changes in sediment
nutrient fluxes resulting from a whole lake sediment capping trial using a modified zeolite phosphorus inactivation agent
(Z2G1). Sediment nutrient fluxes in the hypolimnion were estimated as the residual term in a nutrient budget model that accounted
for mineralisation of organic nutrients, nutrient uptake by phytoplankton and mixing, nitrification, adsorption/desorption
and diffusion of dissolved nutrients at the thermocline. Of the total hypolimnetic phosphate and ammonium fluxes during one
period of seasonal stratification (2007–08), up to 60 and 50%, respectively, were derived from the bottom sediments, 18 and
24% were due to mineralisation of organic species, 36 and 28% were due to phytoplankton uptake and 9 and 6% were from diffusion
across the thermocline. Adsorption/desorption of phosphate to suspended solids and nitrification were of minor (<8%) importance
to the total fluxes. Any reduction in sediment nutrient release by Z2G1 was small compared with both the total sediment nutrient
flux and the sum of other hypolimnetic fluxes. Uneven sediment coverage of Z2G1 may have been responsible for the limited
effect of the sediment capping layer formed by Z2G1. 相似文献
104.
105.
Volpi Denise Alves Fabiana Villa da Silva Arguelho Alan do Vale Marcos Martinez Deniz Matheus Zopollatto Maity 《International journal of biometeorology》2021,65(10):1695-1705
International Journal of Biometeorology - The aim of this study was to estimate, using data mining, which microclimate and behavioral variables affect the behavior of animals to seek shaded or... 相似文献
106.
107.
Time-dependent changes in superoxide dismutase, catalase, xanthine dehydrogenase and oxidase activities in focal cerebral ischaemia 总被引:2,自引:0,他引:2
Time-dependent changes in the activities of antioxidant enzymes and an oxidant enzyme, xanthine oxidase (XO), were detected in primary and peri-ischaemic brain regions during permanent occlusion of the middle cerebral artery (MCAO) in rats. There were no changes in superoxide dismutase (SOD) and catalase (CAT) activities after 3 h of MCAO, whereas antioxidant enzyme activities decreased significantly in ischaemic brain areas following 24 h of ischaemia. After 48 h, the enzyme activities returned to the baseline but then a further increase was observed in ischaemic brain areas by 72 h post-ischaemia. Normally, XO exists as a dehydrogenase (XD), but it is converted to XO which contributes to injury in some ischaemic tissues. The XO activity increased slightly at 3 h after ischaemia, but after 24 h of ischaemia it returned to the baseline and then remained relatively unchanged in ischaemic areas. Pretreatment with allopurinol before ischaemia prevented changes in SOD and CAT activities and attenuated brain oedema during 24 h of ischaemia. Neither XO nor XD activity changed in allopurinol-treated rats at the times of ischaemia. These results indicated that ischaemic brain tissue remained vulnerable to free radical damage for as long as 48 h after ischaemia, and XO was probably not an important source of free radicals in cerebral ischaemia. 相似文献
108.
Park B Nguyen NT Dutt P Merdek KD Bashar M Sterpetti P Tosolini A Testa JR Toksoz D 《The Journal of biological chemistry》2002,277(47):45361-45370
109.
110.
In this study, we aimed to investigate the distribution pattern of ubiquitin and p97/VCP in the rat retina during postnatal
development. Eyeballs from 1-, 4-, 10-, 36- and 72-week-old rats were examined by immunohistochemistry, and protein colocalization
was determined by immunofluorescence microscopy. In the 1-week-old rat retina, p97/VCP was strongly expressed in the neuroblast
layer, however no ubiquitin immunoreactivity was observed. p97/VCP immunoreactivity was present in the ganglion cell layer
(GCL), inner nuclear layer (INL), outer nuclear layer (ONL), inner segment (IS) of the photoreceptor layer, and retinal pigment
epithelium in the 4- and 10-week-old rat retinas. p97/VCP immunoreactivity increased significantly in the 10-week-old rat
retinas. Ubiquitin was barely seen in the 4-week-old rat retinas, and ubiquitin expression was weak in the GCL and the IPL
of the 10-week-old rat retinas. In the 36- and 72-week-old rats, the presence of ubiquitin was remarkable in the IS, INL,
IPL and GCL, however, p97/VCP immunoreactivity was significantly decreased. Colocalization of ubiquitin and p97/VCP was also
observed in the INL, IS, GCL and ONL of 36- and 72-week-old rat retinas. Our results indicate that p97/VCP immunoreactivity
in the retina significantly decreases after rats reach 10 weeks of age, whereas ubiquitin immunoreactivity increases with
aging. These results suggest that an altered expression pattern of p97/VCP and ubiquitin in the developing rat retina may
associate with age-related retinal degeneration. 相似文献