Post-stroke neurogenesis and the neurovascular niche: Newly born neuroblasts localize to peri-infarct cortex in close association with the vascular endothelium

An agonist-induced Ca2+ influx pathway in vascular endothelium and other nonexcitable cells is closely aligned with the depletion of microsomal Ca2+ stores. The mechanism by which this occurs is unknown. In these studies 2',5',-di(tert-butyl-1,4-benzohydroquinone, a specific inhibitor of the microsomal Ca(2+)-adenosinetriphosphatase, and patch-clamp recordings were used to evaluate the relationship of inward Ca2+ current to the depletion of intracellular Ca2+ stores. The results demonstrate that depletion and refilling of Ca2+ stores control the amplitude of an electrogenic influx pathway in vascular endothelium. Prominent fluctuations in Ca2+ current occur when there is an imbalance between depletion and refilling of the stores. Furthermore, the studies suggest that the Ca2+ influx pathway is spatially in close association with the intracellular store.

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Immunocytochemical Localization of Amyloid Protein AA in the “Dense Fibrillar Inclusions” of the Reticuloendothelical Cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100079632 ◽

1977 ◽

Vol 35 ◽

pp. 438-439

Author(s):

T. Shirahama ◽

M. Skinner ◽

A.S. Cohen

Keyword(s):

Amyloid Fibril ◽

Close Association ◽

Gel Filtration ◽

Fibril Formation ◽

Amyloid Protein ◽

Electron Microscopic ◽

Amyloid Deposits ◽

Amyloid Fibril Formation ◽

Electron Microscopic Technique ◽

Lysosomal System

A1thought the mechanisms of amyloidogenesis have not been entirely clarified, proteolysis of the parent proteins may be one of the important steps in the amyloid fibril formation. Recently, we reported that "dense fibrillar inclusions" (DFI), which had the characteristics of lysosomes and contained organized fibrillar profiles as well, were observed in the reticuloendothelial cells in close association with the foci of new amyloid deposits. We considered the findings as evidence for the involvement of lysosomal system in amyloid fibril formation (l). In the present study, we attempted to determine the identity of the contents of the DFI by the use of antisera against the amyloid protein (AA) and an immuno-electron microscopic technique.Amyloidosis was induced in CBA/J mice by daily injections of casein (l). AA was isolated from amyloid-laden spleens by gel filtration and antibody to it was produced in rabbits (2). For immunocytochemistry, the unlabeled antibody enzyme method (3) was employed.

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Linear Arrays of Helical Polyribosomes in Cells Exposed to Antitumor Drug Vincristine Sulfate

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100063706 ◽

1969 ◽

Vol 27 ◽

pp. 358-359

Author(s):

Awtar Krishan

Keyword(s):

Close Association ◽

Annulate Lamellae ◽

Large Array ◽

Vincristine Sulfate ◽

Linear Arrays ◽

Golgi Membranes ◽

Related Drug ◽

Drug Leads ◽

Lethal Doses ◽

Vinblastine Sulfate

Earle's L-929 fibroblasts treated with mitosis-arresting but sub-lethal doses of vinblastine sulfate (VLB) show hypertrophy of the granular endoplasmic reticulum and annulate lamellae. Exposure of the cells to heavier doses of vincristine sulfate (VCR), a VLB-related drug, leads to the accumulation of large amounts of helical polyribosomes, Golgi membranes and crystals in the cytoplasm. In many of these cells a large number of helical polyribosomes are arranged in prominent linear rows, some of which may be up to 5 micrometers in length. Figure 1 shows a large array of helical polyribosomes near a crystalline mass (CRS) in an Earle's L-929 fibroblast exposed to VCR (5ϒ/ml.) for 3 hours At a higher magnification, as seen in figure 2, the helical polyribosomes are seen arranged in parallel rows. In favorably cut sections, a prominent backbone like "stalk" of finely granular material, measuring approximately 300Å in width is seen in close association with the linear rows of helical polyribosomes.

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SEM analysis of fish scale cross sections: A technique study

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100124124 ◽

1992 ◽

Vol 50 (1) ◽

pp. 744-745

Author(s):

M.E. Lee ◽

A. Moller ◽

P.S.O. Fouche ◽

I.G Gaigher

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Cross Sections ◽

Soft Tissues ◽

Close Association ◽

Sem Analysis ◽

Fish Scale ◽

Fish Scales ◽

Micro Structures ◽

Scanning Electron

Scanning electron microscopy of fish scales has facilitated the application of micro-structures to systematics. Electron microscopy studies have added more information on the structure of the scale and the associated cells, many problems still remain unsolved, because of our incomplete knowledge of the process of calcification. One of the main purposes of these studies has been to study the histology, histochemistry, and ultrastructure of both calcified and decalcified scales, and associated cells, and to obtain more information on the mechanism of calcification in the scales. The study of a calcified scale with the electron microscope is complicated by the difficulty in sectioning this material because of the close association of very hard tissue with very soft tissues. Sections often shatter and blemishes are difficult to avoid. Therefore the aim of this study is firstly to develop techniques for the preparation of cross sections of fish scales for scanning electron microscopy and secondly the application of these techniques for the determination of the structures and calcification of fish scales.

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Brain Imaging Could Predict Aphasia Post-Stroke

ASHA Leader ◽

10.1044/leader.rib2.21102016.14 ◽

2016 ◽

Vol 21 (10) ◽

pp. 14-14

Keyword(s):

Brain Imaging ◽

Post Stroke

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Intensive Treatment May Improve Verbal Communication in Patients with Post-Stroke Chronic Aphasia

ASHA Leader ◽

10.1044/leader.rib2.22112017.15 ◽

2017 ◽

Vol 22 (11) ◽

pp. 15-15 ◽

Cited By ~ 1

Keyword(s):

Verbal Communication ◽

Intensive Treatment ◽

Post Stroke ◽

Chronic Aphasia

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Transcranial Electrical Stimulation in Post-Stroke Cognitive Rehabilitation

European Psychologist ◽

10.1027/1016-9040/a000238 ◽

2016 ◽

Vol 21 (1) ◽

pp. 55-64 ◽

Cited By ~ 4

Author(s):

Silvia Convento ◽

Cristina Russo ◽

Luca Zigiotto ◽

Nadia Bolognini

Keyword(s):

Electrical Stimulation ◽

Cognitive Rehabilitation ◽

Cognitive Disorders ◽

Spatial Neglect ◽

Transcranial Electrical Stimulation ◽

Clinical Settings ◽

Post Stroke ◽

Neuropsychological Disorders ◽

Current State ◽

Stimulation Technique

Abstract. Cognitive rehabilitation is an important area of neurological rehabilitation, which aims at the treatment of cognitive disorders due to acquired brain damage of different etiology, including stroke. Although the importance of cognitive rehabilitation for stroke survivors is well recognized, available cognitive treatments for neuropsychological disorders, such as spatial neglect, hemianopia, apraxia, and working memory, are overall still unsatisfactory. The growing body of evidence supporting the potential of the transcranial Electrical Stimulation (tES) as tool for interacting with neuroplasticity in the human brain, in turn for enhancing perceptual and cognitive functions, has obvious implications for the translation of this noninvasive brain stimulation technique into clinical settings, in particular for the development of tES as adjuvant tool for cognitive rehabilitation. The present review aims at presenting the current state of art concerning the use of tES for the improvement of post-stroke visual and cognitive deficits (except for aphasia and memory disorders), showing the therapeutic promises of this technique and offering some suggestions for the design of future clinical trials. Although this line of research is still in infancy, as compared to the progresses made in the last years in other neurorehabilitation domains, current findings appear very encouraging, supporting the development of tES for the treatment of post-stroke cognitive impairments.

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