• 1 DNA methylation and development. 复制标题 收藏 收藏

    【DNA甲基化和发展。】 复制标题 收藏 收藏
    DOI:10.1016/0167-4781(90)90076-e 复制DOI
    作者列表:Cedar H,Razin A
    BACKGROUND & AIMS: -2
    背景与目标: -2
  • 【产后睾丸促性腺激素受体,血清促性腺激素和睾丸激素浓度的变化以及公牛睾丸的功能发育。】 复制标题 收藏 收藏
    DOI:10.1530/rep.1.00768 复制DOI
    作者列表:Bagu ET,Cook S,Gratton CL,Rawlings NC
    BACKGROUND & AIMS: :The primary objectives of this study were to follow the temporal patterns of testicular LH and FSH receptor (LH-R and FSH-R) concentrations and affinity (Ka) during sexual maturation in bulls and to see if such patterns could help explain the control of rapid testicular growth that occurs after 25 weeks of age, when serum gonadotropin concentrations are low. Separate groups of Hereford x Charolais calves (n = 6) were castrated every 4 weeks from 5 to 33 weeks of age and at 56 weeks of age. A week prior to castrations, from 5 to 33 weeks of age, blood was collected every 15 min for 10 h. The transition from indifferent supporting cells to Sertoli cells in seminiferous tubules was rapid between 13 and 25 weeks and rapid testis growth occurred after 25 weeks of age. Serum LH and FSH concentrations were transiently elevated at 12 weeks of age (P < 0.05). LH-R concentrations decreased from 13 to 25 weeks of age and increased to 56 weeks of age (P < 0.05). LH-RKa decreased from 9 to 17 weeks of age, increased to 29 weeks of age and declined to 33 weeks of age (P < 0.05). FSH-R concentrations declined from 17 to 25 weeks of age then increased to 56 weeks of age (P < 0.05). FSH-RKa increased from 17 to 25 weeks of age (P < 0.05). High concentrations of gonadotropins and their receptors may be critical to initiate testis growth postnatally and support it after 25 weeks of age in the face of low serum gonadotropin concentrations.
    背景与目标: :本研究的主要目的是追踪公牛性成熟过程中睾丸LH和FSH受体(LH-R和FSH-R)浓度和亲和力(Ka)的时间模式,并观察这种模式是否有助于解释控制因素血清促性腺激素浓度低时,在25周龄后出现睾丸快速生长的情况。从5到33周龄和56周龄每4周cast割一次赫瑞福德x夏洛来牛犊(n = 6)组。 5至33周龄weeks割前一周,每15分钟收集一次血液,持续10 h。在13至25周之间,从生精小管中的冷漠支持细胞向Sertoli细胞的过渡迅速,并且25周龄后睾丸迅速生长。血清LH和FSH浓度在12周龄时短暂升高(P <0.05)。 LH-R浓度从13周龄降低到25周龄,增加到56周龄(P <0.05)。 LH-RKa从9周龄降低到17周龄,增加到29周龄,下降到33周龄(P <0.05)。 FSH-R浓度从17周下降到25周,然后上升到56周(P <0.05)。 FSH-RKa从17周龄增加到25周龄(P <0.05)。高浓度的促性腺激素及其受体对于出生后开始睾丸生长并在25周龄后面对低血清促性腺激素浓度的情况下支持睾丸生长可能至关重要。
  • 【氨基末端脑钠肽:一种诊断,预后和管理心力衰竭的生物标志物。】 复制标题 收藏 收藏
    DOI:10.1586/14737159.6.5.649 复制DOI
    作者列表:Morello AM,Januzzi JL
    BACKGROUND & AIMS: :There is a substantial need for a diagnostic tool to aid in the early diagnosis of heart failure and in the recognition of those at risk for its development, as well as in guidance of therapy. Testing for amino-terminal pro-brain natriuretic peptide (NT-proBNP) has been recognized to have utility in the diagnosis, prognosis and management of heart failure. In addition, numerous other applications for NT-proBNP testing are now recognized, such as evaluation of patients with heart disease in the absence of heart failure, as well as the diagnostic and prognostic evaluation of patients with acute coronary syndromes or pulmonary thromboembolism.
    背景与目标: :非常需要一种诊断工具来辅助心力衰竭的早期诊断,并认识到可能发展为心力衰竭的人,以及指导治疗。氨基末端脑钠肽(NT-proBNP)的检测已被认为可用于心力衰竭的诊断,预后和管理。此外,现在还认可了NT-proBNP测试的许多其他应用,例如在没有心力衰竭的情况下对心脏病患者的评估以及对急性冠状动脉综合征或肺血栓栓塞患者的诊断和预后评估。
  • 【人脑中的微透析:其应用综述。】 复制标题 收藏 收藏
    DOI:10.1080/01616412.1997.11740814 复制DOI
    作者列表:Hamani C,Luer MS,Dujovny M
    BACKGROUND & AIMS: The analysis of brain extracellular fluid can provide essential information about both the physiology and the pathology of the human nervous system. The introduction of microdialysis into the clinical sciences has provided a new opportunity to study this environment. Using microdialysis, endogenous substances can be obtained and drugs can be delivered in very close proximity to the receptors and ion channels on neuronal membranes. In this sense, microdialysis can be regarded as a novel technique since it can continuously measure interstitial brain activity in living tissue while causing minimal adverse effects. Although it has been well established as an experimental technique for neurochemistry, the true utility of microdialysis as a clinical tool is still being defined. The potential clinical applications of microdialysis to characterize the human brain extracellular environment in patients with pathologic conditions has grown rapidly. The number of publications in which microdialysis has been performed in clinical studies has been increasing during recent years and this article gives a summary of those reports where microdialysis was applied in the study of human brain disorders.

    背景与目标: 对大脑细胞外液的分析可以提供有关人类神经系统生理和病理的基本信息。将微透析技术引入临床科学为研究这种环境提供了新的机会。使用微透析,可以获得内源性物质,并且药物可以非常靠近神经元膜上的受体和离子通道递送。从这个意义上讲,微透析可以被视为一种新颖的技术,因为它可以连续测量活组织中的间质性大脑活动,同时将不良影响降到最低。尽管已经将其很好地确立为神经化学的实验技术,但微透析作为临床工具的真正用途仍在定义中。微透析在表征病理状况患者中表征人脑细胞外环境的潜在临床应用迅速增长。近年来,在临床研究中进行微透析的出版物数量不断增加,本文总结了在人类脑部疾病研究中应用微透析的那些报道。

  • 【苯巴比妥依赖和戒断大鼠脑中谷氨酸受体,c-fos mRNA表达和激活蛋白-1(AP-1)DNA结合活性的变化。】 复制标题 收藏 收藏
    DOI:10.1016/s0006-8993(97)00134-0 复制DOI
    作者列表:Tanaka S,Kiuchi Y,Numazawa S,Oguchi K,Yoshida T,Kuroiwa Y
    BACKGROUND & AIMS: We studied changes in glutamate receptors, expression of immediate early genes, and AP-1 DNA binding activity in the brains of phenobarbital (PB)-dependent and -withdrawn rats to investigate the possible involvement of activation of glutamate receptors in PB withdrawal syndrome. PB-dependent rats were prepared by feeding drug-admixed food for 5 weeks. Autoradiographic analysis showed that binding of [3H(+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imin e (MK-801), an antagonist of N-methyl-D-aspartic acid (NMDA) receptors, increased significantly in the cerebral cortices of PB-dependent and 24-h-withdrawn rats. However, [3H]MK-801 binding in the hippocampus and [3H]6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) and [3H]kainic acid binding in the hippocampus and cerebral cortex were essentially unchanged in both groups. PB withdrawal seizures were followed by increased expression of c-fos mRNA in the hippocampus and cerebral cortex and of c-jun mRNA in the cerebral cortex. The induction of c-fos and c-jun mRNA was suppressed by administration of MK-801. Furthermore, PB withdrawal enhanced AP-1 DNA binding activity in the brain. The present findings suggest functional enhancement of glutamatergic neurotransmission during the development of PB withdrawal syndrome.

    背景与目标: 我们研究了苯巴比妥(PB)依赖和戒断大鼠大脑中谷氨酸受体的变化,立即早期基因的表达以及AP-1 DNA结合活性,以研究谷氨酸受体激活在PB戒断综合征中的可能。通过喂食药物混合的食物5周来制备PB依赖的大鼠。放射自显影分析表明,[3H()-5-甲基-10,11-二氢-5H-二苯并[a,d]环庚烯-5,10-亚胺e(MK-801)与N-甲基- D-天冬氨酸(NMDA)受体,在PB依赖和24小时戒断大鼠的大脑皮层中显着增加。然而,在海马中的[3H] MK-801结合以及在海马和大脑皮层中的[3H] 6-氰基-7-硝基喹喔啉-2,3-二酮(CNQX)和[3H]海藻酸结合基本上没有变化。组。 PB抽搐发作后,海马和大脑皮层中c-fos mRNA的表达增加,大脑皮层中c-jun mRNA的表达增加。通过施用MK-801抑制了c-fos和c-jun mRNA的诱导。此外,PB撤离可增强大脑中AP-1 DNA的结合活性。目前的发现表明,在PB戒断综合征的发展过程中,谷氨酸能神经传递的功能增强。

  • 【ROS形成对依赖NADH的底物支持的孤立的脑线粒体中DeltaPsim的中等依赖性。】 复制标题 收藏 收藏
    DOI:10.1007/s11064-006-9130-y 复制DOI
    作者列表:Tretter L,Adam-Vizi V
    BACKGROUND & AIMS: :The membrane potential (DeltaPsim) dependence of the generation of reactive oxygen species (ROS) in isolated guinea-pig brain mitochondria respiring on NADH-linked substrates (glutamate plus malate) was addressed. Depolarization by FCCP was without effect on H(2)O(2) formation in the absence of bovine serum albumin (BSA). Addition of BSA (0.025%) to the assay medium hyperpolarized mitochondria by 6.1 +/- 0.9 mV (from 169 +/- 3 to 175.1 +/- 2.1 mV) and increased the rate of H(2)O(2) formation from 207 +/- 4.5 to 312 +/- 12 pmol/min/mg protein. Depolarization by FCCP (5-250 nM) in the presence of BSA decreased H(2)O(2) formation but only to the level observed in the absence of BSA. Rotenone stimulated the formation of H(2)O(2) both in the absence and presence of BSA. It is suggested that H(2)O(2) formation in mitochondria supported by NADH-linked substrates is sensitive to changes in DeltaPsim only when mitochondria are highly polarized and even then, 60% of ROS generation is independent of DeltaPsim. This is in contrast to earlier reports on the highly DeltaPsim sensitive ROS formation related to reverse electron flow observed in well-coupled succinate-supported mitochondria.
    背景与目标: :膜电位(DeltaPsim)依赖于在NADH相连的底物(谷氨酸加苹果酸)上呼吸的豚鼠脑线粒体中分离的活性氧(ROS)的产生。在没有牛血清白蛋白(BSA)的情况下,通过FCCP去极化对H(2)O(2)的形成没有影响。将BSA(0.025%)添加到测定介质超极化线粒体的6.1 /-0.9 mV(从169 /-3到175.1 /-2.1 mV),并将H(2)O(2)的形成速率从207 /-增加4.5至312 /-12 pmol / min / mg蛋白质。在BSA存在下由FCCP(5-250 nM)进行的去极化降低了H(2)O(2)的形成,但仅达到了在没有BSA的情况下观察到的水平。鱼藤酮在没有和存在BSA的情况下刺激H(2)O(2)的形成。建议仅在线粒体高度极化并且即使那时,60%的ROS生成独立于DeltaPsim时,由NADH链接的底物支持的线粒体中的H(2)O(2)形成对DeltaPsim的变化敏感。这与早先报道的关于高度DeltaPsim敏感的ROS形成相反,后者与在耦合良好的琥珀酸负载的线粒体中观察到的反向电子流有关。
  • 【正常成年大鼠的血脑屏障缺陷区域的免疫环境增强。】 复制标题 收藏 收藏
    DOI:10.1016/s0165-5728(97)00038-6 复制DOI
    作者列表:Pedersen EB,McNulty JA,Castro AJ,Fox LM,Zimmer J,Finsen B
    BACKGROUND & AIMS: The circumventricular organs (CVOs) in the brain are without a blood-brain barrier (BBB) and as such directly exposed to blood plasma constituents and blood-borne pathogens. In light of previous studies showing discrepancies regarding the immunocompetence of these organs, we initiated the present study to provide a comprehensive immunohistochemical analysis of the cellular expression of immune-associated antigens within the pineal gland, area postrema and the subfornical organ. In all CVOs, subpopulations of cells morphologically similar to complement receptor type 3 immunoreactive microglial/macrophage cells expressed major histocompatibility complex (MHC) class II antigen, leucocyte common antigen (LCA/CD45), as well as CD4 and ED1 antigen. Based on morphological criteria the MHC class II antigen expressing cells could be grouped into a major population of classical parenchymal and perivascular ramified microglial cells and a minor population presenting itself as scattered or small groups of rounded macrophage-like cells. CD4 and ED1 antigen were expressed by both cell types. CD45 was preferentially expressed by macrophage-like cells. MHC class I antigen was expressed by the vascular endothelium in both BBB-protected and BBB-deficient areas and was additionally present as a lattice-like network throughout the BBB-deficient parenchyma in all CVOs. The results suggest that the BBB-free areas of the brain besides being constantly surveyed by blood-borne macrophages, possess an intrinsic immune surveillance system based on resting and activated microglial cells, which may function as a non-endothelial, cellular barrier against blood-borne pathogens.

    背景与目标: 大脑中的室间隔器官(CVO)没有血脑屏障(BBB),因此直接暴露于血浆成分和血源性病原体。鉴于先前的研究表明这些器官的免疫能力存在差异,我们启动了本研究,以提供对松果体,视网膜后区域和分支下器官内免疫相关抗原的细胞表达的全面免疫组织化学分析。在所有CVO中,与补体受体3型免疫反应性小胶质细胞/巨噬细胞细胞形态相似的细胞亚群表达了主要的组织相容性复合物(MHC)II类抗原,白细胞常见抗原(LCA / CD45)以及CD4和ED1抗原。根据形态学标准,可以将表达MHC II类抗原的细胞分为经典的实质和血管周围分枝的小神经胶质细胞的主要群体,以及表现为散在的或成团的圆形巨噬细胞样细胞的少数群体。 CD4和ED1抗原通过两种细胞类型表达。 CD45优先由巨噬细胞样细胞表达。 MHC I类抗原在BBB保护区和BBB缺失区均由血管内皮表达,并在所有CVO中的整个BBB缺失实质中均呈格子状网络存在。结果表明,除了大脑中无血脑屏障的区域不断被血源性巨噬细胞检查外,还具有基于静止和活化的小胶质细胞的内在免疫监视系统,该系统可能起非内皮细胞屏障的作用。传播的病原体。

  • 【神经元自噬:从发育到变性。】 复制标题 收藏 收藏
    DOI:10.1016/j.mam.2006.08.009 复制DOI
    作者列表:Boland B,Nixon RA
    BACKGROUND & AIMS: :Macroautophagy, a lysosomal pathway responsible for the turnover of organelles and long-lived proteins, has been regarded mainly as an inducible process in neurons, which is mobilized in states of stress and injury. New studies show, however, that macroautophagy is also constitutively active in healthy neurons and is vital to cell survival. Neurons in the brain, unlike cells in the periphery, are protected from large-scale autophagy induction because they can use several different energy sources optimally, receive additional nutrients and neurotrophin support from glial cells, and benefit from hypothalamic regulation of peripheral nutrient supplies. Due to its exceptional efficiency, constitutive autophagy in healthy neurons proceeds in the absence of easily detectable autophagic vacuole intermediates. These intermediates can accumulate rapidly, however, when late steps in the autophagic process are blocked. Autophagic vacuoles also accumulate abnormally in affected neurons of several major neurodegenerative diseases, including Alzheimer's disease and Parkinson's disease, where they have been linked to various aspects of disease pathogenesis including neuronal cell death. The build-up of autophagic vacuoles in these neurological disorders and others may reflect either heightened autophagy induction, impairment in later digestive steps in the autophagy pathway, or both. Determining the basis for AV accumulation is critical for understanding the pathogenic significance of autophagy in a given pathologic state and for designing possible therapies based on modulating autophagy. In this review, we discuss the special features of autophagy regulation in the brain, its suspected roles in neurodevelopment and plasticity, and recent progress toward understanding how dysfunctional autophagy contributes to neurodegenerative disease.
    背景与目标: :巨噬细胞吞噬,一种负责细胞器和长寿蛋白质更新的溶酶体途径,主要被认为是神经元的诱导过程,在压力和损伤状态下被动员。然而,新研究表明,巨噬细胞自噬在健康神经元中也具有组成性活性,对细胞存活至关重要。与周围的细胞不同,大脑中的神经元可以免受大规模自噬的诱导,因为它们可以最佳地利用几种不同的能源,可以从神经胶质细胞中获得更多的营养和神经营养蛋白支持,并受益于下丘脑对周围营养供应的调节。由于其出色的效率,健康神经元中的组成型自噬在缺乏易于检测的自噬液泡中间体的情况下进行。但是,当自噬过程的后期步骤被阻滞时,这些中间体会迅速积累。自噬空泡还在几种主要的神经退行性疾病(包括阿尔茨海默氏病和帕金森氏病)的受影响神经元中异常蓄积,它们与疾病发病机制的各个方面(包括神经元细胞死亡)相关。在这些神经系统疾病和其他神经系统疾病中,自噬泡的形成可能反映了自噬诱导的增强,自噬途径中以后消化步骤的损伤或两者兼而有之。确定AV积累的基础对于理解给定病理状态下自噬的致病意义以及基于调节自噬设计可能的治疗方法至关重要。在这篇综述中,我们讨论了大脑中自噬调节的特殊功能,其在神经发育和可塑性中的可疑作用,以及在理解功能失调自噬如何导致神经退行性疾病方面的最新进展。
  • 【神经元活动的同步促进单个大鼠新皮层神经元在早期发育中的存活。】 复制标题 收藏 收藏
    DOI:10.1111/j.1460-9568.1997.tb01449.x 复制DOI
    作者列表:Voigt T,Baier H,Dolabela de Lima A
    BACKGROUND & AIMS: Neural activity is thought to play a significant role during the development of the cerebral cortex. In this study, we examined the effects of global activity block or enhancement and the effects of patterned firing on the ability of cultured rat neocortical neurons to survive during the second week in vitro, beyond the beginning of synaptogenesis. Blockade of neuronal activity by adding tetrodotoxin (TTX) and increasing magnesium concentration in the medium strongly reduced the survival of cortical cells. Increasing neuronal activity by raising the external potassium concentration significantly improved the survival of cortical neurons. We postulated that in a developing neuronal network the survival of nerve cells is regulated by synaptically mediated events that involve changes in the intracellular calcium concentration. To examine this question further, we monitored the activity of the developing network by optically recording the intracellular calcium signals of many neurons simultaneously. These recordings show that in low magnesium neocortical neurons express synchronized oscillation of their intracellular calcium concentration. The ability of a network to synchronize the changes in intracellular calcium of multiple cells appeared gradually during the second week in culture, paralleled by both an increase in the synaptic density and a decline in the number of surviving neurons. By examining the fate of identified cells several days after a recording session, we found that those nerve cells that were co-activated with other neurons had a significantly higher chance to survive than cells that did not participate in synchronized events. These experiments demonstrate that during early cortical network development cortical neurons show synchronized firing activity and that the survival of neurons is at least partially dependent on this pattern of neuronal activity.

    背景与目标: 人们认为神经活动在大脑皮层的发育过程中起着重要的作用。在这项研究中,我们研究了整体活动阻滞或增强的作用以及图案化放电对培养的大鼠新皮层神经元在体外第二周(突触形成开始之后)存活的能力的影响。通过添加河豚毒素(TTX)和增加培养基中镁的浓度来阻止神经元活性,这会大大降低皮质细胞的存活率。通过提高外部钾离子浓度来增加神经元活性可以显着改善皮层神经元的存活率。我们推测,在发育中的神经元网络中,神经细胞的存活受到涉及细胞内钙浓度变化的突触介导事件的调节。为了进一步检查这个问题,我们通过光学记录许多神经元的细胞内钙信号同时监测了发育中网络的活动。这些记录表明,在低镁状态下,新皮层神经元表达其细胞内钙浓度的同步振荡。在培养的第二周内,网络同步多个细胞的细胞内钙变化的能力逐渐显现,同时突触密度增加和存活神经元数量减少。通过在录制会话几天后检查识别出的细胞的命运,我们发现与其他神经元共激活的神经细胞比不参与同步事件的细胞具有更高的存活机会。这些实验表明,在早期皮质网络发育过程中,皮质神经元显示出同步的放电活动,并且神经元的存活至少部分取决于这种神经元活动模式。

  • 【T(2)加权的microMRI和诱发的低髓鞘转基因小鼠的发展过程中视觉系统测量的潜力。】 复制标题 收藏 收藏
    DOI:10.1007/s11064-006-9121-z 复制DOI
    作者列表:Martin M,Reyes SD,Hiltner TD,Givogri MI,Tyszka JM,Fisher R,Campagnoni AT,Fraser SE,Jacobs RE,Readhead C
    BACKGROUND & AIMS: :Our objective was to follow the course of a dysmyelinating disease followed by partial recovery in transgenic mice using non-invasive high-resolution (117 x 117 x 70 microm) magnetic resonance (microMRI) and evoked potential of the visual system (VEP) techniques. We used JOE (for J37 golli overexpressing) transgenic mice engineered to overexpress golli J37, a product of the Golli-mbp gene complex, specifically in oligodendrocytes. Individual JOE transgenics and their unaffected siblings were followed from 21 until 75-days-old using non-invasive in vivo VEPs and 3D T2-weighted microMRI on an 11.7 T scanner, performing what we believe is the first longitudinal study of its kind. The microMRI data indicated clear, global hypomyelination during the period of peak myelination (21-42 days), which was partially corrected at later ages (>60 days) in the JOE mice compared to controls. These microMRI data correlated well with [Campagnoni AT (1995) "Molecular biology of myelination". In: Ransom B, Kettenmann H (eds) Neuroglia--a Treatise. Oxford University Press, London, pp 555-570] myelin staining, [Campagnoni AT, Macklin WB (1988) Cellular and molecular aspects of myelin protein gene-expression. Mol Neurobiol 2:41-89] a transient intention tremor during the peak period of myelination, which abated at later ages, and [Lees MB, Brostoff SW (1984) Proteins in myelin. In: Morell (ed) Myelin. Plenum Press, New York and London, pp 197-224] VEPs which all indicated a significant delay of CNS myelin development and persistent hypomyelination in JOE mice. Overall these non-invasive techniques are capable of spatially resolving the increase in myelination in the normally developing and developmentally delayed mouse brain.
    背景与目标: :我们的目标是通过非侵入性高分辨率(117 x 117 x 70 microm)磁共振(microMRI)和诱发视觉系统(VEP)技术追踪转基因小鼠的运动异常,然后部分恢复。我们使用经工程改造过表达Golli-mbp基因复合物产物Golli J37(特别是在少突胶质细胞中)的JOE(用于J​​37 golli过表达)转基因小鼠。从21岁到75天大,使用11.7 T扫描仪上的非侵入性体内VEP和3D T2加权显微MRI对个体JOE转基因及其未受影响的兄弟姐妹进行跟踪研究,我们认为这是同类研究中的首次纵向研究。显微MRI数据表明,在峰值髓鞘形成期(21-42天)期间出现了明显的整体性低髓鞘形成,与对照组相比,JOE小鼠在以后的年龄(> 60天)中得到了部分纠正。这些显微MRI数据与[Campagnoni AT(1995)“髓鞘形成的分子生物学”)有很好的相关性。在:Ransom B,Kettenmann H(eds)Neuroglia-专着中。牛津大学出版社,伦敦,第555-570页]髓磷脂染色,[Campagnoni AT,Macklin WB(1988)髓磷脂蛋白基因表达的细胞和分子方面。 [Mol Neurobiol 2:41-89]在髓鞘形成高峰期发生短暂的意向性震颤,此现象在以后的年龄有所减轻,[Lees MB,Brostoff SW(1984)蛋白在髓鞘中。在:莫雷尔(编辑)髓磷脂。 [Plenum Press,纽约和伦敦,第197-224页] VEP均表明JOE小鼠的CNS髓磷脂发育显着延迟和持续性髓鞘减少。总体而言,这些非侵入性技术能够在空间上解决正常发育和发育迟缓的小鼠大脑中髓鞘形成的增加。
  • 【胎儿小脑发育的磁共振成像。】 复制标题 收藏 收藏
    DOI:10.1080/14734220600589210 复制DOI
    作者列表:Triulzi F,Parazzini C,Righini A
    BACKGROUND & AIMS: :In the last few years fetal magnetic resonance imaging (MRI) has been proposed as a second level technique in the evaluation of fetal brain anomalies. It has been demonstrated that MRI is highly accurate in illustrating the morphologic changes of developing brain and fetal brain abnormalities being a useful procedure when ultrasonography is inconclusive or doubtful. Starting from the 19-20 weeks gestational age (GA), MRI can reliably depict fetal brain anatomy and locating pathology, offering a robust and reliable tool in the assessment of fetal CNS diseases. In this review both in vivo MRI quantitative and qualitative data about fetal cerebellar development are presented and compared with ultrasonography data. Fetal cerebellar development is gradual, steady, and largely comparable to the development of the supratentorial brain. Archicerebellar (flocculo-nodular lobe) and paleocerebellar (vermis) structures develop first, whereas neocerebellum (cerebellar hemispheres) develop slowly and largely after birth.
    背景与目标: :在最近几年中,胎儿磁共振成像(MRI)已被提出作为评估胎儿脑异常的第二级技术。已经证明,当超声检查不确定或值得怀疑时,MRI可以高度准确地说明发育中的大脑和胎儿脑部异常的形态变化,这是一种有用的方法。从19-20周胎龄(GA)开始,MRI可以可靠地描绘胎儿的大脑解剖结构和定位病理,从而为评估胎儿CNS疾病提供了强大而可靠的工具。在这篇综述中,提出了关于胎儿小脑发育的体内MRI定量和定性数据,并将其与超声检查数据进行了比较。胎儿小脑发育是渐进的,稳定的,并且在很大程度上可与上脑上脑的发育相媲美。先生小脑(结节状结节状)和小脑((状)结构,而新小脑(小脑半球)出生后缓慢且大部分发育。
  • 【体内形成SMAC的成熟免疫突触介导病毒感染的星形胶质细胞从大脑中清除。】 复制标题 收藏 收藏
    DOI:10.1084/jem.20060420 复制DOI
    作者列表:Barcia C,Thomas CE,Curtin JF,King GD,Wawrowsky K,Candolfi M,Xiong WD,Liu C,Kroeger K,Boyer O,Kupiec-Weglinski J,Klatzmann D,Castro MG,Lowenstein PR
    BACKGROUND & AIMS: :The microanatomy of immune clearance of infected brain cells remains poorly understood. Immunological synapses are essential anatomical structures that channel information exchanges between T cell-antigen-presenting cells (APC) during the priming and effector phases of T cells' function, and during natural killer-target cell interactions. The hallmark of immunological synapses established by T cells is the formation of the supramolecular activation clusters (SMACs), in which adhesion molecules such as leukocyte function-associated antigen 1 segregate to the peripheral domain of the immunological synapse (p-SMAC), which surrounds the T cell receptor-rich or central SMAC (c-SMAC). The inability so far to detect SMAC formation in vivo has cast doubts on its functional relevance. Herein, we demonstrate that the in vivo formation of SMAC at immunological synapses between effector CD8+ T cells and target cells precedes and mediates clearance of virally infected brain astrocytes.
    背景与目标: :对被感染的脑细胞免疫清除的微观解剖学知之甚少。免疫突触是必不可少的解剖结构,可在T细胞功能的启动阶段和效应阶段以及自然杀伤分子与靶细胞的相互作用期间,引导T细胞抗原呈递细胞(APC)之间的信息交换。 T细胞建立的免疫突触的标志是超分子激活簇(SMAC)的形成,其中粘附分子(如白细胞功能相关抗原1)分离到免疫突触(p-SMAC)的外围结构域,周围T细胞受体丰富或中央SMAC(c-SMAC)。迄今为止,尚无法在体内检测到SMAC的形成,对其功能相关性产生了疑问。在本文中,我们证明了在效应CD8 T细胞和靶细胞之间的免疫突触中SMAC的体内形成先于并介导了病毒感染的脑星形胶质细胞的清除。
  • 【PedsQL脑肿瘤模块:初始可靠性和有效性。】 复制标题 收藏 收藏
    DOI:10.1002/pbc.21026 复制DOI
    作者列表:Palmer SN,Meeske KA,Katz ER,Burwinkle TM,Varni JW
    BACKGROUND & AIMS: BACKGROUND:Brain tumors (BT) are second only to acute lymphoblastic leukemia as the most prevalent form of pediatric cancer, with BT 5-year survival rates approaching 70%. With increased survival, quality of life has emerged as an essential health outcome. This investigation examines the internal consistency reliability and construct validity of the Pediatric Quality of Life Inventory (PedsQL) Brain Tumor Module. METHODS:The PedsQL 4.0 Generic Core Scales, PedsQL Multidimensional Fatigue Scale, and PedsQL Brain Tumor Module were administered to 99 families. The average age of the 56 boys and 43 girls was 9.76 years (range=2-18 years). The sample included children with tumors located in the posterior fossa/brainstem (N=62, 62.6%), supratentorial (N=15, 15.2%), and midline (N=22, 22.2%). Children were on treatment (N=46, 46.5%), off treatment<12 months (N=19, 19.2%), or off treatment>12 months/long-term survivor (N=34, 34.3%). Treatment included radiation (N=61, 61.6%), surgery (N=83, 83.8%), chemotherapy (N=87, 87.9%), and bone marrow transplant (N=5, 5.1%). RESULTS:Internal consistency reliability was demonstrated for the 24-item PedsQL Brain Tumor Module (average alpha=0.78-0.92, parent proxy-report, n=99; average alpha=0.76-0.87, child self-report, n=51). Construct validity for the PedsQL Brain Tumor Module was supported through an analysis of the intercorrelations with the Generic Core Scales and Fatigue Scale. CONCLUSIONS:The findings provide support for the measurement properties of the PedsQL Brain Tumor Module.
    背景与目标: 背景:脑肿瘤(BT)仅次于急性淋巴细胞白血病,是儿童癌症的最普遍形式,其BT 5年生存率接近70%。随着生存率的提高,生活质量已成为一种必不可少的健康结果。这项研究检查了儿童生命质量量表(PedsQL)脑肿瘤模块的内部一致性可靠性和构建效度。
    方法:将PedsQL 4.0通用核心量表,PedsQL多维疲劳量表和PedsQL脑肿瘤模块应用于99个家庭。 56名男孩和43名女孩的平均年龄为9.76岁(范围= 2-18岁)。样本包括肿瘤位于后颅窝/脑干(N = 62,62.6%),幕上(N = 15,15.2%)和中线(N = 22,22.2%)的儿童。儿童接受治疗(N = 46,46.5%),不接受治疗<12个月(N = 19,19.2%)或不接受治疗> 12个月/长期幸存者(N = 34,34.3%)。治疗包括放疗(N = 61,61.6%),手术(N = 83,83.8%),化学疗法(N = 87,87.9%)和骨髓移植(N = 5,5.1%)。
    结果:24项PedsQL脑肿瘤模块具有内部一致性可靠性(平均α= 0.78-0.92,父母代理报告,n = 99;平均α= 0.76-0.87,孩子自我报告,n = 51)。通过分析通用核心量表和疲劳量表之间的相互关系,支持了PedsQL脑肿瘤模块的构建效度。
    结论:这些发现为PedsQL脑肿瘤模块的测量特性提供了支持。
  • 【口服用多糖凝胶包衣的小丸的开发1.物理机械性能。】 复制标题 收藏 收藏
    DOI:10.1016/j.ijpharm.2006.07.004 复制DOI
    作者列表:Sriamornsak P,Burton MA,Kennedy RA
    BACKGROUND & AIMS: :Spherical pellets containing theophylline, calcium acetate and microcrystalline cellulose were extruded and spheronized, before being coated with six different pectins or alginates by interfacial complexation. The aim of this study was to discover the effect of the coatings on physico-mechanical properties that will be crucial in determining the pellets' utility as sustained release systems. An insoluble, smooth and uniformly thick coat of calcium polysaccharide was formed around the core pellets. A factorial experiment was designed to investigate the effect of pellet size and polysaccharide type and concentration on the entrapment efficiency, mechanical properties and other physical characteristics. Coated pellets were observed by scanning electron microscopy and, depending on the particular polysaccharide used, the dry coats were found to be 30-80 microm thick. The size of pellet, the type and concentration of polysaccharide influenced the yield of theophylline in the coated pellets. Although the mechanical properties of the pellets were improved by applying any of the gel coats, use of an alginate with a high content of guluronic acid or an amidated pectin coating gave the best results. This is probably because both of these have significant potential to form very stable cross-links within the gel coats.
    背景与目标: :将含有茶碱,乙酸钙和微晶纤维素的球形小球挤出并滚圆,然后通过界面络合用六种不同的果胶或藻酸盐包衣。这项研究的目的是发现包衣对物理机械性能的影响,这对于确定微丸作为缓释系统的用途至关重要。在核心药丸周围形成了不溶的,光滑且均匀厚的钙多糖涂层。设计了析因实验,以研究颗粒大小,多糖类型和浓度对包封效率,机械性能和其他物理特性的影响。通过扫描电子显微镜观察包衣的小丸,并且根据所使用的特定多糖,发现干衣的厚度为30-80微米。药丸的大小,多糖的类型和浓度影响了包衣药丸中茶碱的产量。尽管可通过使用任何凝胶包衣来改善丸粒的机械性能,但使用具有高含量古洛糖醛酸的藻酸盐或酰胺化果胶包衣的效果最佳。这可能是因为这两者都具有在凝胶涂层内形成非常稳定的交联的巨大潜力。
  • 【鲨鱼脑中一种含有羟脯氨酸的蛋白质,与髓磷脂碱性蛋白质有关。】 复制标题 收藏 收藏
    DOI:10.1111/j.1471-4159.1990.tb04958.x 复制DOI
    作者列表:Wood DD,McLaurin J,Moscarello MA
    BACKGROUND & AIMS: :Myelin basic protein (MBP) from shark (Chondricthyes) consists of a simpler mixture of charge isomers than human MBP. About two-thirds of the total amount applied to a CM-52 cellulose cation-exchange column was recovered in the unbound fraction of the column; the remaining one-third bound to column and was eluted as a single OD280 peak. This bound material did not sow the usual pattern of charge microheterogeneity found with human or bovine MBP. The unbound fraction was composed of a high molecular weight protein (55-60 kDa), which constituted most of this protein fraction and a low molecular weight protein (approximately 18 kDa). The amino acid composition of our unbound fraction was similar to that reported earlier. The Glx (glutamic acid + glutamine) was increased about threefold whereas the Arg content was only about 25% of that of the 18.5 kDa variant of bovine or human origin. The presence of hydroxyproline (1.2 residues/100) in this protein was noteworthy, identification of which was achieved by amino acid analysis in two different systems and by mass spectrometry. In the precolumn derivatization method, hydroxyproline eluted at 2.7 min; in the postcolumn derivatization method it eluted at 12.2 min. Identification of hydroxyproline was completed by fast atom bombardment-mass spectral analysis. The effect of hydroxyproline on the secondary structure of this protein is being studied. Verification that this high molecular weight protein contained MBP sequences within its primary structure was confirmed by immunological methods.(ABSTRACT TRUNCATED AT 250 WORDS)
    背景与目标: :鲨鱼(Chondricthyes)的髓磷脂碱性蛋白(MBP)由电荷异构体组成的混合物比人MBP更简单。应用于CM-52纤维素阳离子交换柱的总量的约三分之二是在该柱的未结合馏分中回收的;剩余的三分之一与色谱柱结合,并以一个OD280峰洗脱。这种结合的材料并未播种人或牛MBP常见的电荷微异质性模式。未结合的部分由高分子量蛋白质(55-60 kDa)和低分子量蛋白质(约18 kDa)组成,其中高分子量蛋白质占该蛋白质部分的大部分。我们未结合部分的氨基酸组成与先前报道的相似。 Glx(谷氨酸谷氨酰胺)增加了约三倍,而Arg含量仅为牛或人来源的18.5 kDa变体的Arg含量的约25%。值得注意的是,该蛋白质中存在羟脯氨酸(1.2个残基/ 100个),通过在两个不同系统中进行氨基酸分析并通过质谱法进行鉴定。在柱前衍生化方法中,羟脯氨酸在2.7分钟洗脱;在柱后衍生化方法中,它在12.2分钟时洗脱。通过快速原子轰击质谱分析完成了羟脯氨酸的鉴定。羟脯氨酸对该蛋白二级结构的影响正在研究中。通过免疫学方法证实了这种高分子量蛋白质在其一级结构中包含MBP序列。(摘要截短为250字)

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