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51.
Proteomic changes in the brain of the western painted turtle (Chrysemys picta bellii) during exposure to anoxia 下载免费PDF全文
During anoxia, overall protein synthesis is almost undetectable in the brain of the western painted turtle. The aim of this investigation was to address the question of whether there are alterations to specific proteins by comparing the normoxic and anoxic brain proteomes. Reductions in creatine kinase, hexokinase, glyceraldehyde‐3‐phosphate dehydrogenase, and pyruvate kinase reflected the reduced production of adenosine triphosphate (ATP) during anoxia while the reduction in transitional endoplasmic reticulum ATPase reflected the conservation of ATP or possibly a decrease in intracellular Ca2+. In terms of neural protection programed cell death 6 interacting protein (PDCD6IP; a protein associated with apoptosis), dihydropyrimidinase‐like protein, t‐complex protein, and guanine nucleotide protein G(o) subunit alpha (Go alpha; proteins associated with neural degradation and impaired cognitive function) also declined. A decline in actin, gelsolin, and PDCD6IP, together with an increase in tubulin, also provided evidence for the induction of a neurological repair response. Although these proteomic alterations show some similarities with the crucian carp (another anoxia‐tolerant species), there are species‐specific responses, which supports the theory of no single strategy for anoxia tolerance. These findings also suggest the anoxic turtle brain could be an etiological model for investigating mammalian hypoxic damage and clinical neurological disorders. 相似文献
52.
目的:探讨帕金森病(PD)伴轻度认知功能障碍(PD-MCI)的相关因素及临床特征,找出帕金森病伴轻度认知功能障碍的预测因子。方法:参照运动障碍协会工作组推荐的帕金森病伴轻度认知功能障碍的诊断标准,用蒙特利尔认知功能评估量表(Mo C A)及帕金森病统一评定量表(Ⅰ~Ⅲ)对81例PD患者进行评估。结果:81例PD患者中47例为轻度认知功能障碍,占58%,23例无认知功能障碍,占28%;14%PD-MCI病人病程小于5年。PD-MCI组与帕金森病不伴有认知功能障碍(PD-NCI)组在文化程度、HY分期、每日左旋多巴等效剂量(LEDD)上差异有统计学意义(P0.05);视空间/执行功能、延迟记忆、注意力、语言、抽象能力认知域差异有统计学意义(P0.05);UPDRSⅢ、姿势不稳步态障碍(PIGD)差异有统计学意义(P0.05);Mo CA评分与年龄(r=-0.31,P0.05)、HY分期(r=-0.44,P0.05)、UPDRS-Ⅲ分数(r=-0.32,P0.05)、UPDRS-Ⅱ(r=-0.35,P0.05)、UPDRS-Ⅰ(r=-0.40,P0.05)、迟缓(r=-0.38,P0.05)、PIGD呈负相关(r=-0.31,P0.05),与教育程度呈正相关(r=0.30,P0.05)。纳入Mo CA评分为因变量,年龄、教育程度、HY分期、UPDRS-Ⅲ分数、UPDRS-Ⅱ分数、UPDRS-Ⅰ分数为自变量行多元线性回归分析,年龄(βcoefficients-0.06,P0.05)和HY分期(βcoefficients-0.80,P0.05)为帕金森病伴轻度认知功能障碍的预测因子;为观察UPDRSⅢ中亚项评分对认知功能的独立影响,单独纳入迟缓和PIGD评分为自变量,结果迟缓为帕金森病伴轻度认知功能障碍的预测因子(βcoefficients-0.12,P0.05)。结论:MCI是PD患者中发生率较高的一种非运动症状,以视空间/执行功能、延迟记忆、注意力、语言功能障碍为主。患者的认知功能和年龄、教育程度、疾病严重程度、运动障碍密切相关,特别是迟缓与姿势不稳/步态障碍。年龄、HY分期、迟缓为PD-MCI的预测因子。 相似文献
53.
目的:探讨氯胺酮麻醉下的MECT治疗难治性抑郁症的安全性和治疗前后的认知功能变化。方法:入组60例需要MECT治疗的难治性抑郁症患者,随机分为氯胺酮组(30例)使用氯胺酮诱导麻醉的MECT治疗;异丙酚组(30例)使用异丙酚诱导麻醉的MECT治疗。入组患者在基线期及MECT治疗8次后完成汉密尔顿抑郁量表(HAMD)评定及连线测验AB、威斯康星卡片分类测验、汉诺塔测试,出组时评定副反应量表。结果:两组患者治疗结束后认知功能均较治疗前明显降低,异丙酚组较氯胺酮组降低更明显。结论:氯胺酮MECT治疗难治性抑郁症安全有效,对患者的认知功能损害较异丙酚组轻,未出现严重副作用。 相似文献
54.
Elizabeth D. Miller Norbert W. Seidler 《Biochemical and biophysical research communications》2010,391(2):1297-1300
Postoperative Cognitive Dysfunction (POCD) is associated with increased mortality in the elderly and may occur from lipid peroxidation in aging. We previously showed that sevoflurane sequesters acrolein, which promotes the formation of a novel species of a putative neuromelanin. The current study examined the properties of this serotonin-derived melanoid (SDM). The interaction of SDM with unilamellar vesicles (ULVs) was examined using lipid membrane probes. Vesicle disruption was investigated by leakage of dye from calcein-loaded ULVs. We observed that SDM decreased diphenyl-hexatriene fluorescence anisotropy and increased the temperature-dependent change in anisotropy. SDM changed the absorbance of merocyanin-bound ULVs. SDM increased detergent-mediated calcein leakage. SDM structure was dramatically altered upon interaction with ULVs. We also observed that SDM enhanced detergent-mediated leakage of loaded ULVs, suggesting that SDM may be neurotoxic. We propose that inhalational agents, which sequester acrolein, may promote the production of certain species of neuromelanin that depletes local serotonin and enhances neuronal vulnerability. 相似文献
55.
56.
摘要 目的:分析自拟益气通阳活血方治疗阿尔茨海默病的临床效果。方法:选取2020年10月~2022年4月于中国人民解放军空军军医大学第一附属医院接受治疗的阿尔茨海默病患者104例,依据入院先后顺序编号,按单双号分为对照组(n=52)和研究组(n=52)。对照组进行常规西药治疗,研究组在此基础上进行自拟益气通阳活血方治疗。比较两组临床疗效、治疗前后中医证候积分、日常生活活动能力、认知功能、血清去甲肾上腺素(NE)、多巴胺(DA)、乙酰胆碱转移酶(ChAT)水平、β淀粉样蛋白前体(APP)、β淀粉样蛋白1-42(Aβ1-42)、丙二醛(MDA)、超氧化物歧化酶(SOD)水平,并比较两组安全性。结果:治疗后,两组中医证候积分均降低,且研究组显著低于对照组(P<0.05);研究组总有效率为94.23%,明显高于对照组的78.85%(P<0.05);治疗后,两组简易智能精神状态检查量表(MMSE)评分与蒙特利尔认知评估量表(MoCA)评分研究组均高于对照组(P<0.05);治疗后,两组barthel指数评分及日常生活能力量表(ADL)评分研究组均显著高于对照组(P<0.05);治疗后,两组DA、NE、ChAT水平均升高,且研究组明显高于对照组(P<0.05);治疗后,两组SOD水平升高,APP、Aβ1-42、MDA水平均降低(P<0.05),且与对照组相比研究组各指标变化更显著(P<0.05);两组治疗期间的不良反应均较轻微,经对症处理后均缓解,不良反应发生率比较无明显差异(P>0.05)。结论:自拟益气通阳活血方治疗阿尔茨海默病疗效显著,可降低中医证候积分,提高认知功能,调节NE、DA、ChAT水平,抑制APP、Aβ1-42水平,提高其日常生活活动能力,且安全性高。 相似文献
57.
摘要 目的:探讨帕金森病(PD)患者血清激肽释放酶6(klk6)、热休克蛋白70(HSP70)水平与病情严重程度以及PD轻度认知障碍(PD-MCI)的关系。方法:选择2021年2月至2022年2月徐州医科大学附属医院收治的165例PD患者(PD组),根据修订的Hoehn-Yahr分级将PD患者分为早期组(1.0~2.5级,59例)、中期组(3.0级,65例)和晚期组(4.0~5.0 级,41例),根据是否存在PD-MCI将PD患者分为PD-MCI组(66例)和非PD-MCI组(99例),另选择同期72例于我院门诊体检的健康志愿者为对照组。检测血清klk6、HSP70水平,比较不同分组血清klk6、HSP70水平差异,多因素Logistic回归分析影响PD患者发生PD-MCI的因素。结果:PD组血清klk6水平高于对照组(P<0.05),HSP70水平低于对照组(P<0.05),晚期组血清klk6水平高于早期组和中期组,且中期组血清klk6水平均高于早期组(P<0.05),晚期组血清HSP70水平低于早期组和中期组,且中期组血清HSP70水平低于早期组(P<0.05);PD-MCI组血清klk6水平高于非PD-MCI组(P<0.05),HSP70水平低于非PD-MCI组(P<0.05)。多因素Logistic回归分析结果显示年龄偏高、修订的Hoehn-Yahr分级晚期、高水平klk6是PD患者发生PD-MCI的危险因素(P<0.05),高水平HSP70是PD患者发生PD-MCI的保护因素(P<0.05)。结论:PD患者血清klk6水平增高,HSP70水平降低与修订的Hoehn- Yahr分级增加以及PD-MCI有关,检测血清klk6、HSP70水平有助于评估PD病情以及PD-MCI风险。 相似文献
58.
V. P. Lyashenko O. Z. Mel’nikova A. V. Gorkovenko S. M. Lukashov T. G. Chaous 《Neurophysiology》2007,39(1):64-75
We examined the dynamics of the spectral powers and indices of frequency components of background field electrical activity
recorded from tropho-and ergotropic zones of the rat hypothalamus (electrohypothalamogram, EHtG) in the course of long-term
(21 weeks) emotional stress induced by a zooconflict situation. Low-frequency delta-range (0.5 to 3.5 Hz) oscillations dominated
in EHtGs recorded from both hypothalamic zones of both control and stressed animals. The integral power of EHtG oscillations
underwent significant changes within the observation period; it considerably increased on the 6th to 9th week, dropped within
the 12th to 18th week, and, after this (up to the 21st week) again increased, i.e., the dynamics, in general, were threephase.
The dynamics of the power of separate frequency components of EHtG showed certain similarities to the dynamics of the integral
power. Changes in the EHtG power in stressed animals were characterized by a shorter duration and greater rate; the powers
of all EHtG components in these animals were lower than in control ones within a greater part of the observation period. The
dynamics of the normalized powers and of the indices of different EHtG rhythms in stressed and control animals, especially
the dynamics of dominating oscillations of the delta and theta ranges, were to a certain extent opposite. Our data show that
changes in the EHtG can be electrographic correlates of subsequent phases of a long-lasting stress reaction of the organism
in the course of the experiment; specific features of manifestation of these modifications in the tropho-and ergotropic hypothalamic
zones are related to a certain specificity of the hormonal/transmitter mechanisms in the structures under study.
Neirofiziologiya/Neurophysiology, Vol. 39, No. 1, pp. 69–80, January–February, 2007. 相似文献
59.
Llorenç Milà i Canals Christian Bauer Jochen Depestele Alain Dubreuil Ruth Freiermuth Knuchel Gérard Gaillard Ottar Michelsen Ruedi Müller-Wenk Bernt Rydgren 《The International Journal of Life Cycle Assessment》2007,12(1):5-15
Background, Aim and Scope
Land use by agriculture, forestry, mining, house-building or industry leads to substantial impacts, particularly on biodiversity
and on soil quality as a supplier of life support functions. Unfortunately there is no widely accepted assessment method so
far for land use impacts. This paper presents an attempt, within the UNEP-SETAC Life Cycle Initiative, to provide a framework
for the Life Cycle Impact Assessment (LCIA) of land use.
Materials and Methods:
This framework builds from previous documents, particularly the SETAC book on LCIA (Lindeijer et al. 2002), developing essential
issues such as the reference for occupation impacts; the impact pathways to be included in the analysis; the units of measure
in the impact mechanism (land use interventions to impacts); the ways to deal with impacts in the future; and bio-geographical
differentiation.
Results:
The paper describes the selected impact pathways, linking the land use elementary flows (occupation; transformation) and parameters
(intensity) registered in the inventory (LCI) to the midpoint impact indicators and to the relevant damage categories (natural
environment and natural resources). An impact occurs when the land properties are modified (transformation) and also when
the current man-made properties are maintained (occupation).
Discussion:
The size of impact is the difference between the effect on land quality from the studied case of land use and a suitable reference
land use on the same area (dynamic reference situation). The impact depends not only on the type of land use (including coverage
and intensity) but is also heavily influenced by the bio-geographical conditions of the area. The time lag between the land
use intervention and the impact may be large; thus land use impacts should be calculated over a reasonable time period after
the actual land use finishes, at least until a new steady state in land quality is reached.
Conclusions:
Guidance is provided on the definition of the dynamic reference situation and on methods and time frame to assess the impacts
occurring after the actual land use. Including the occupation impacts acknowledges that humans are not the sole users of land.
Recommendations and Perspectives:
The main damages affected by land use that should be considered by any method to assess land use impacts in LCIA are: biodiversity
(existence value); biotic production potential (including soil fertility and use value of biodiversity); ecological soil quality
(including life support functions of soil other than biotic production potential). Bio-geographical differentiation is required
for land use impacts, because the same intervention may have different consequences depending on the sensitivity and inherent
land quality of the environment where it occurs. For the moment, an indication of how such task could be done and likely bio-geographical
parameters to be considered are suggested. The recommendation of indicators for the suggested impact categories is a matter
of future research. 相似文献
60.
《Revista espa?ola de geriatría y gerontología》2022,57(3):174-181
Background and objectivesThe ageing population and the increasing dependency associated with it, makes the caregiver a highly relevant figure nowadays. The present study analyzes the socio-demographic differences between family and professional caregivers and their satisfaction and implication in a training program for caregivers.MethodsThe sample consisted of 59 caregivers of older people (37 were family caregivers and 22 professional caregivers) which received and implemented a caregivers training program in their daily care functions. These caregivers were trained in communication skills and cognitive stimulation strategies so they could use them in their daily care activities with the older adults under their care during a period of 3 months. All the participants were assessed with a socio-demographic questionnaire, 2 questionnaires to analyze their satisfaction with their work and the training received and one questionnaire to analyze their ability to detect and react to memory and behavior problems in the older adults they attended.ResultsThe results showed socio-demographic differences, improvements in satisfaction in family caregivers and a greater commitment in their daily work after the treatment in both groups although these effects could be due to different reasons.ConclusionsThe research shows the benefits of carrying out training programs for caregivers as they significantly increase the quality and satisfaction with caregiving. The study also displays the need to adjust such programs taking into account that the socio-demographic characteristics and training needs are different depending on whether de caregiver is a family member or a professional. 相似文献