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521.
Mahdi Goudarzvand Mohammad Javan Javad Mirnajafi-Zadeh Sabah Mozafari Taki Tiraihi 《Cellular and molecular neurobiology》2010,30(2):289-299
Cognitive deficits have been observed in patients with multiple sclerosis (MS) due to hippocampal insults. Antioxidant vitamins
D and E are suggested for patients suffering from neurodegenerative diseases like MS, while their mechanisms of action are
not well understood. Here, we have tried to study the effects of these vitamins on demyelination, cell death, and remyelination
of rat hippocampus following local ethidium bromide (EB) injection. Animals received 100 mg/kg vitamin E or 5 μg/kg of vitamin
D3 for 2, 7, or 28 days. The extent of demyelination, myelin staining intensity, and expression of myelin basic protein and
caspase-3 were investigated using histological and immunoblotting verification. Administration of EB alone caused demyelination,
cell death, and afterward an endogenous repair. Vitamins E and D3 reduced the EB-induced damage and increased the endogenous
remyelination of hippocampus. Although the anti-apoptotic effect of these vitamins and protection against demyelination were
predictable based on their antioxidant effect, our results indicated the positive effect of vitamins E and D3 on process of
remyelination by endogenous progenitor cells and supported their possible therapeutic effects in the context of demyelinating
diseases like MS. 相似文献
522.
523.
The occurrence of Aphelinus paramali (Zehavi & Rosen) (Hym., Aphelinidae) was evidenced from North east Iran, in association with Aphis pomi (de Geer). This species is reported from Iran for the first time, and A. pomi is introduced as a new host for this parasitoid. Detailed morphological characters were studied with scanning electron microscopy (SEM) photographs. Also, sequences of ribosomal internal transcribed spacer 2 (ITS2) and cytochrome oxidase subunit I (COI) genes were used for determining species boundaries and comparing with other Aphelinus species. Different results were obtained in phylogenetic analysis of these two regions. Analysis of COI gene supported the closer relationship of this species with Aphelinus abdominalis. This is the first data about comprehensive characterization of a parasitic wasp using morphological characters, SEM and two‐locus information from Iran. 相似文献
524.
This paper includes studies on Heliotropium marifolium complex from India. Five new combinations in Euploca from H. sect. Orthostachys are proposed here. H. marifolium, H. marifolium subsp. wallichii, H. rottleri, H. cornutum and H. madurense are transferred to the genus Euploca. The taxonomic status of the unresolved name H. rottleri is also discussed. 相似文献
525.
Sandro D. Badilatti Patrik Christen Alina Levchuk Javad Hazrati Marangalou Bert van Rietbergen Ian Parkinson Ralph Müller 《Biomechanics and modeling in mechanobiology》2016,15(1):83-95
Identification of individuals at risk of bone fractures remains challenging despite recent advances in bone strength assessment. In particular, the future degradation of the microstructure and load adaptation has been disregarded. Bone remodeling simulations have so far been restricted to small-volume samples. Here, we present a large-scale framework for predicting microstructural adaptation in whole human vertebrae. The load-adaptive bone remodeling simulations include estimations of appropriate bone loading of three load cases as boundary conditions with microfinite element analysis. Homeostatic adaptation of whole human vertebrae over a simulated period of 10 years is achieved with changes in bone volume fraction (BV/TV) of less than 5 %. Evaluation on subvolumes shows that simplifying boundary conditions reduces the ability of the system to maintain trabecular structures when keeping remodeling parameters unchanged. By rotating the loading direction, adaptation toward new loading conditions could be induced. This framework shows the possibility of using large-scale bone remodeling simulations toward a more accurate prediction of microstructural changes in whole human bones. 相似文献
526.