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1.
In the present study, we addressed the question of whether treatment with mannitol, an osmotic diuretic, affects astrogliovascular responses to status epilepticus (SE). In saline-treated animals, astrocytes exhibited reactive astrogliosis in the CA1-3 regions 2-4 days after SE. In the mannitol-treated animals, a large astroglial empty zone was observed in the CA1 region 2 days after SE. This astroglial loss was unrelated to vasogenic edema formation. There was no difference in SE-induced neuronal loss between saline- and mannitol-treated animals. Furthermore, mannitol treatment did not affect astroglial loss and vasogenic edema formation in the dentate gyrus and the piriform cortex. These findings suggest that mannitol treatment induces selective astroglial loss in the CA1 region independent of vasogenic edema formation following SE. These findings support the hypothesis that the susceptibility of astrocytes to SE is most likely due to the distinctive heterogeneity of astrocytes independent of hemodynamics. [BMB Reports 2015; 48(9): 507-512] 相似文献
2.
Dr Chunki Piplai 《International Journal of Anthropology》1991,6(4):233-236
The Tamang women tea-labouren of Jalpaiguri district show no significant difference in age at menopause among their three «migration status» groups, viz., MO, M1 and M2+. The mean age at menopause is 47.3±4.26 and the median age is 47.68 years. A significant difference occurs between the observed mean age at menopause and 45 years, which is generally taken to be the menopausal age by convention. These Tamang women seem to be similar to other hill women in respect of age at menopause. 相似文献
3.
Douglas M. Carlson William L. Pflieger Linden Trial Pamela S. Haverland 《Environmental Biology of Fishes》1985,14(1):51-59
Synopsis
Scaphirhynchus albus and S. platorynchus were studied in Missouri during 1978–1979 to assess their distribution and abundance, to obtain information on their life
histories, and to identify existing or potential threats to their survival. S. platorynchus was collected in substantial numbers (4355 specimens) at all 12 sampling stations in the Missouri and Mississippi rivers,
while only 11 S. albus were captured from 6 stations. Twelve specimens identified in the field as hybrids between the two species were captured
from 4 stations. Morphometric and meristic comparisons of presumed hybrids with the parent species, using cluster and principal
components analyses, demonstrated intermediacy of most specimens identified in the field as hybrids. Aquatic insects comprised
most of the diet of S. platorynchus and S. albus, but S. albus and the hybrids had consumed considerable quantities of fish. S. albus grew more rapidly than S. platorynchus, while the growth of hybrids was intermediate. Hybridization appears to be a recent phenomenon, resulting from man-caused
changes in the big-river environment. Hybridization may be a threat to survival of S. albus in the study streams. 相似文献
4.
Enamel hypoplasia was recorded for the primary and permanent teeth of Natufians (terminal Pleistocene Hunter-Gatherers) and
Early Arabs (Subsistence farmers). Minimal hypoplasia was found in the primary teeth of the Natufians, but in the Early Arab
population, 31% of upper first primary molars showed enamel defects. In the permanent teeth, the Early Arab population again
showed a significantly higher frequency of hypoplasia, with all teeth affected. In the Natufians, only later developing teeth
showed enamel defects. These findings suggest that health status in the Early Arab population was poor throughout life, affecting
pregnant mothers, their foetuses, young infants and children. These results confirm other studies that have shown deterioration
in health status of early agriculturalists relative to hunter- gatherers. Comparisons of these findings with those of recent
populations indicate that health status in the Natufians was comparable to that of modern populations with subsistence diets
and mediocre health care. Health status in the Early Arab population was comparable to that of modern populations suffering
from severe malnutrition and chronic disease. 相似文献
5.
《Electromagnetic biology and medicine》2013,32(4):436-448
The aim of the study was to investigate the effects of extremely low-frequency electric field (ELF EF) on visual evoked potential (VEP), thiobarbituric acid reactive substances (TBARS), total antioxidant status (TAS), total oxidant status (TOS), and oxidant stress index (OSI). Thirty female Wistar rats, aged 3 months, were divided into three equal groups: Control (C), the group exposed to EF at 12 kV/m strength (E12), and the group exposed to EF at 18 kV/m strength (E18). Electric field was applied to the E12 and E18 groups for 14 days (1 h/day). Brain and retina TBARS, TOS, and OSI were significantly increased in the E12 and E18 groups with respect to the control group. Also, TBARS levels were significantly increased in the E18 group compared with the E12 group. Electric fields significantly decreased TAS levels in both brain and retina in E12 and E18 groups with respect to the control group. All VEP components were significantly prolonged in rats exposed to electric fields compared to control group. In addition, all latencies of VEP components were increased in the E18 group with respect to the E12 group. It is conceivable to suggest that EF-induced lipid peroxidation may play an important role in changes of VEP parameters. 相似文献
6.
Status epilepticus (SE) is a life threatening condition that often precedes the development of epilepsy. Traditional treatments for epilepsy have been focused on targeting neuronal mechanisms contributing to hyperexcitability, however, approximately 30% of patients with epilepsy do not respond to existing neurocentric pharmacotherapies. A growing body of evidence has demonstrated that profound changes in the morphology and function of astrocytes accompany SE and persist in epilepsy. Astrocytes are increasingly recognized for their diverse roles in modulating neuronal activity, and understanding the changes in astrocytes following SE could provide important clues about the mechanisms underlying seizure generation and termination. By understanding the contributions of astrocytes to the network changes underlying epileptogenesis and the development of epilepsy, we will gain a greater appreciation of the contributions of astrocytes to dynamic circuit changes, which will enable us to develop more successful therapies to prevent and treat epilepsy. This review summarizes changes in astrocytes following SE in animal models and human temporal lobe epilepsy and addresses the functional consequences of those changes that may provide clues to the process of epileptogenesis. 相似文献
7.
Didone?FrigerioEmail author Katharina?Hirschenhauser Erich?M?stl John?Dittami Kurt?Kotrschal 《Acta ethologica》2004,7(1):9-18
Testosterone modulates male vertebrates sexual and social behaviour. We experimentally investigated the testosterone-sensitive behaviours in male greylag geese (Anser anser) by implanting silastic tubes containing crystalline testosterone during the mating season (February; 5 implanted and 5 control males) and in the early winter (November; 7 and 7). Focal animals were part of a semi-tame, unrestrained flock with fully intact social relationships. Excreted testosterone and corticosterone immunoreactive metabolites (TM, BM) were determined by enzyme immunoassay. Individual faecal samples and behavioural protocols were collected daily over a period of 5 weeks, including 1 control week before implantation. In February, no significant behavioural effects of the supplemental testosterone were observed, which may be due to the naturally occurring high systemic androgen levels in spring. In November, however, implanted males had higher TM excretion rates and performed status signalling behaviour (beak up) more frequently than control males. No differences between implanted and control males were found with respect to BM, agonistic interactions or vigilance behaviour. Furthermore, during the second week after implantation, TM positively correlated with the frequency of beak up of implanted males, whilst their female partners were attacked with lower latency by other members of the flock than the females of control males. Hence, status signalling in greylag ganders seems to be testosterone-sensitive year-long and inappropriate status signalling of males may draw attacks towards their females. 相似文献
8.
9.
目的:探讨姜黄素(curcumin)对癫痫大鼠认知功能障碍的预防作用及其可能机制。方法:将30只成年雄性SD大鼠分为正常对照组、单纯致痫组(SE组)、姜黄素[60mg/(kg·d)]干预组(curcumin组)。采用MorriS水迷宫方法检测大鼠学习记忆功能变化,并检测脑片水平的长时程增强(LTP)变化,处死大鼠后取脑组织并匀浆,测超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH.PX)、谷胱甘肽(GSH)、丙二醛(MDA)的水平。结果:(1)SE组大鼠寻找平台的潜伏期明显长于对照组,具有统计学意义(P〈0.05),姜黄素组寻找平台的潜伏期相对于SE组显著缩短(P〈0.05)。撤离平台后,SE组大鼠在平台所在象限的停留时间明显短于对照组(P〈0.05),姜黄素治疗后大鼠在平台所在象限的停留时间较SE组显著延长(P〈0.05)。(2)给予HFS刺激后各组兴奋性突出后电位(fEPSP)斜率较前明显增加,均可持续1h以上,与对照组比较SE组HFS刺激后fEPSP斜率明显减小(P〈0.05),姜黄素可减轻SE所致的fEPSP斜率减小(P〈0.05)。(3)SE组SOD、GSH—PX、GSH显著下降,MDA明显增高,姜黄素可逆转上述现象,有统计学意义(P〈0.05)。结论:姜黄素可显著减轻癫痫持续状态所致的大鼠认知功能障碍,减轻海马区的氧化应激反应从而保护海马海马是其可能机制之一。 相似文献
10.
Changes in phosphorylation of the NMDA receptor in the rat hippocampus induced by status epilepticus 总被引:4,自引:0,他引:4
Niimura M Moussa R Bissoon N Ikeda-Douglas C Milgram NW Gurd JW 《Journal of neurochemistry》2005,92(6):1377-1385
Systemic administration of pilocarpine preceded by lithium induces status epilepticus (SE) that results in neurodegeneration and may lead to the development of spontaneous recurrent seizures. We investigated the effect of Li/pilocarpine-induced SE on phosphorylation of the NMDA receptor in rat hippocampus. Phosphorylation of NR1 by PKC on Ser890 was decreased to 45% of control values immediately following 1 h of SE. During the first 3 h following the termination of SE, phosphorylation of Ser890 increased 4-fold before declining to control values by 24 h. Phosphorylation of NR1 by PKA was also depressed relative to controls immediately following SE and transiently increased above control values upon the termination of SE. SE was accompanied by a general increase in tyrosine phosphorylation of hippocampal proteins that lasted for several hours following the termination of seizures. Tyrosine phosphorylation of the NR2A and NR2B subunits of the NMDAR increased 3-4-fold over control values during SE, continued to increase during the first hour following SE and then declined to control levels by 24 h. SE resulted in the activation of Src and Pyk2 associated with the postsynaptic apparatus, suggesting a role for these enzymes in the SE-induced increase in tyrosine phosphorylation. Changes in phosphorylation of the NMDA receptor may play a role in the pathophysiological consequences of SE. 相似文献