Oncocytoma of the spinal cord

2001 ◽  
Vol 94 (2) ◽  
pp. 310-312 ◽  
Author(s):  
Se Hoon Kim ◽  
Soya Paik ◽  
Do Heum Yoon ◽  
Tai Seung Kim
Keyword(s):  
Electron Microscopy ◽  
Spinal Cord ◽  
Microscopy Study ◽  
Electron Microscopy Study ◽  
Content Type ◽  
Ultrastructural Findings ◽  
Fine Print

✓ The authors report a case of oncocytoma arising from the spinal cord in a 40-year-old woman who presented with the complaints of gradual difficulty in walking. The excised tumor was exclusively composed of polygonal cells with abundant homogeneous eosinophilic cytoplasms. Electron microscopy study showed densely packed swollen mitochondria and frequent desmosomes. The histological and ultrastructural findings were consistent with a diagnosis of oncocytoma. To the authors' knowledge, this represents the first reported case of oncocytoma of the spinal cord.

Observations on Developing Blood Vessels in Rat Spinal Cord—A High Voltage Electron Microscopy Study

1974 ◽  
Vol 32 ◽  
pp. 66-67
Author(s):  
Richard S. Hannah
Keyword(s):  
Electron Microscopy ◽  
Spinal Cord ◽  
High Voltage ◽  
Microscopy Study ◽  
Electron Microscopy Study ◽  
High Voltage Electron Microscopy ◽  
Thin Sections ◽  
Voltage Electron ◽  
High Voltage Electron ◽  
Transmission Electron

The formation of junctional complexes between endothelial cell processes was examined in rat spinal cords, from age birth to six weeks. Segments of spinal cord were removed from the region of the cervical enlargement and fixed. For comparative purposes, animals from each time group were subdivided into groups, fixed by either immersion or perfusion with an aldehyde combination in sodium cacodylate buffer and embedded in Araldite. Thin sections were examined by conventional transmission electron microscopy. Thick sections (0.5μ - 1.0μ) were stained with uranyl magnesium acetate for four hours at 60°C and lead citrate for 30 mins. and examined in the AEI Mark II High Voltage Electron Microscope.

Fine Surface Structure of an Intraspinal Neurenteric Cyst: A Scanning and Transmission Electron Microscopy Study

Neurosurgery ◽  
1990 ◽  
Vol 27 (5) ◽  
pp. 829-833 ◽  
Author(s):  
Yoshihiro Morita ◽  
Kazuo Kinoshita ◽  
Shinichiro Wakisaka ◽  
Shinji Makihara
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Goblet Cells ◽  
Microscopy Study ◽  
Electron Microscopy Study ◽  
Neurenteric Cyst ◽  
Transmission Electron Microscopy Study ◽  
Transmission Electron ◽  
Fine Surface ◽  
Ultrastructural Findings

Abstract The case of an 11-year-old boy with an intraspinal neurenteric cyst, which recurred 8 years and 3 months after surgery, is presented. Scanning and transmission electron microscopy of the cyst epithelium revealed marked resemblance to that of the respiratory tract, despite the presence of numerous goblet cells mimicking intestine on light microscopy study. Detailed ultrastructural findings are described.

Transitory traumatic paraplegia: electron microscopy of early alterations in myelinated nerve fibers

1972 ◽  
Vol 36 (4) ◽  
pp. 407-415 ◽  
Author(s):  
George J. Dohrmann ◽  
Franklin C. Wagner ◽  
Paul C. Bucy
Keyword(s):  
Electron Microscopy ◽  
Spinal Cord ◽  
White Matter ◽  
Nerve Fibers ◽  
Myelinated Nerve ◽  
Content Type ◽  
Myelinated Nerve Fibers ◽  
Myelin Sheaths ◽  
Fine Print

✓ The white matter of the monkey spinal cord was examined by electron microscopy during the first 4 hours following a contusion sufficient to produce a transitory paraplegia. At 5 min after injury the myelinated nerve fibers resembled those of the control animals. By 15 and 30 min after contusion, selected fibers were noted to have moderately enlarged periaxonal spaces. Attenuated myelin sheaths, splaying of the myelin lamellae, and a marked increase in the periaxonal spaces were present in affected nerve fibers at 1 hr following trauma. By 4 hrs after contusion approximately one-fourth of the fibers showed breakage of the myelin sheaths and consequent denuding of axons or marked attenuation of the myelin sheaths, greatly enlarged periaxonal spaces, and degeneration of the associated axons.

The microvasculature in transitory traumatic paraplegia

1971 ◽  
Vol 35 (3) ◽  
pp. 263-271 ◽  
Author(s):  
George J. Dohrmann ◽  
Franklin C. Wagner ◽  
Paul C. Bucy
Keyword(s):  
Electron Microscopy ◽  
Spinal Cord ◽  
Gray Matter ◽  
Perivascular Spaces ◽  
Central Gray Matter ◽  
Content Type ◽  
Structural Alterations ◽  
Spinal Cord Contusion ◽  
Central Gray ◽  
Fine Print

✓ Fine structural alterations in the microvasculature, primarily of the gray matter, occur as one aspect of experimental spinal cord contusion. A force of 300 gm-cm, shown by the authors to produce a transitory paraplegia, was applied to the T-10 level of exposed primate spinal cord. At 5 min post-contusion, the muscular venules of the central gray matter were distended with erythrocytes. Erythrocytes were seen within the perivascular spaces of the post-capillary venules and muscular venules at 15 and 30 min post-contusion, and there was hemorrhage into the gray matter at 1 hour post-contusion. The appearance of erythrocytes within the perivenular spaces was apparently due to small ruptures in the walls of the muscular venules, which were first demonstrated by electron microscopy 15 min after contusion. Alterations in capillary and post-capillary venule endothelium of both gray and white matter were present at 4 hours post-contusion and consisted of vacuolation and endothelial swelling. In conclusion, following experimental contusion of the spinal cord sufficient to cause a transitory paraplegia, the principal changes were early perivascular and parenchymal hemorrhages followed by later evidence of ischemic endothelial injury in the microvasculature.

Effect of mexiletine on lipid peroxidation and early ultrastructural findings in experimental spinal cord injury

1999 ◽  
Vol 91 (2) ◽  
pp. 200-204 ◽  
Author(s):  
Erkan Kaptanoglu ◽  
Hakan H. Caner ◽  
H. Selçuk Sürücü ◽  
Filiz Akbiyik
Keyword(s):  
Spinal Cord ◽  
Lipid Peroxidation ◽  
Spinal Cord Injury ◽  
Sodium Succinate ◽  
Content Type ◽  
Methylprednisolone Sodium Succinate ◽  
Cord Injury ◽  
Group 3 ◽  
Ultrastructural Findings ◽  
Fine Print

Object. The purpose of this study was to investigate the effect of mexiletine on lipid peroxidation and on ultrastructural findings after induced spinal cord injury (SCI). The authors also compared the activity of mexiletine to that of the well-known antioxidant, methylprednisolone sodium succinate (MPSS). Methods. Wistar rats were divided into seven groups, (Groups 1–7). Those in Groups 1 and 2 were control animals that underwent laminectomy only, after which nontraumatized spinal cord samples were obtained immediately (Group 1) and 2 hours postsurgery (Group 2). Spinal cord injury was induced in all other groups, and cord samples were obtained at 2 hours postsurgery. The rats in Group 3 underwent SCI alone; those in Group 4 received 30 mg/kg of MPSS intraperitoneally immediately after trauma was induced; and those in Groups 5, 6, and 7 received 1, 10, and 50 mg/kg of mexiletine, respectively, by intraperitoneal injection immediately after trauma was induced. Compared with the levels in control animals, lipid peroxidation was significantly elevated in rats in Groups 3 and 5, but there were no statistical differences among those in Groups 1, 2, 4, 6 and 7 in this regard. Compared with the findings in rats in Group 3, ultrastructural damage post-SCI was minor in rats in Groups 4 and 5, and there was even less damage evident in rats in Group 7. Conclusions. Analysis of these findings showed that administration of 50 mg/kg mexiletine significantly decreased the level of lipid peroxidation and protected spinal cord ultrastructure following SCI.

The mechanism of spinal cord cavitation following spinal cord transection

1977 ◽  
Vol 46 (6) ◽  
pp. 745-756 ◽  
Author(s):  
Chun C. Kao ◽  
Louis W. Chang ◽  
James M. B. Bloodworth
Keyword(s):  
Electron Microscopy ◽  
Spinal Cord ◽  
Electron Microscope ◽  
Spinal Cord Transection ◽  
Content Type ◽  
Fine Print

✓ The authors report their findings by electron microscopy after microsurgical subpial spinal cord transection in dogs. After cord transection, conspicuous myelin microcysts are formed in a background of otherwise intact cord tissue at a distance of 1 to 2 mm from the cut end of the cord, both proximal and distal to the transection. Seen through the electron microscope, the microcyst is a myelin sac distended by fluid under pressure, containing a swollen axon filled with excessive axoplasmic organelles; that is, a terminal club. Later the microcysts and terminal clubs rupture. The large spaces within the microcysts are opened to heretofore small extracellular spaces and the spinal cord tissues are destroyed. Thus, microcysts are precursors of large cavities seen at the ends of transected cord stumps. The formation of microcysts and their subsequent rupture, which leads to cord cavitation, is interpreted as an inherent response of cord tissue to injury, and the result of an abortive attempt at cord regeneration.

Factors influencing adhesive bonding at the bone/implant interface

1992 ◽  
Vol 50 (2) ◽  
pp. 1114-1115
Author(s):  
Julie A. Martini ◽  
Robert H. Doremus
Keyword(s):  
Electron Microscopy ◽  
Adhesive Bonding ◽  
Microscopy Study ◽  
Electron Microscopy Study ◽  
Bone Implant ◽  
Factors Influencing ◽  
Lr White ◽  
Transmission Electron ◽  
New Zealand White Rabbits ◽  
Scanning Electron

Tracy and Doremus have demonstrated chemical bonding between bone and hydroxylapatite with transmission electron microscopy. Now researchers ponder how to improve upon this bond in turn improving the life expectancy and biocompatibility of implantable orthopedic devices.This report focuses on a study of the- chemical influences on the interfacial integrity and strength. Pure hydroxylapatite (HAP), magnesium doped HAP, strontium doped HAP, bioglass and medical grade titanium cylinders were implanted into the tibial cortices of New Zealand white rabbits. After 12 weeks, the implants were retrieved for a scanning electron microscopy study coupled with energy dispersive spectroscopy.Following sacrifice and careful retrieval, the samples were dehydrated through a graduated series starting with 50% ethanol and continuing through 60, 70, 80, 90, 95, and 100% ethanol over a period of two days. The samples were embedded in LR White. Again a graduated series was used with solutions of 50, 75 and 100% LR White diluted in ethanol.

Transmission Electron Microscopy study of Bi-based superconducting phases

1990 ◽  
Vol 48 (4) ◽  
pp. 50-51
Author(s):  
J.G. Wen ◽  
K.K. Fung
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Single Crystals ◽  
Microscopy Study ◽  
Electron Microscopy Study ◽  
Space Groups ◽  
Superconducting Phases ◽  
Ceramic Samples ◽  
Transmission Electron ◽  
Modulated Structures

Bi-based superconducting phases have been found to be members of a structural series represented by Bi2Sr2Can−1Cun−1On+4, n=1,2,3, and are referred to as 2201, 2212, 2223 phases. All these phases are incommensurate modulated structures. The super space groups are P2/b, NBbmb 2201, 2212 phases respectively. Pb-doped ceramic samples and single crystals and Y-doped single crystals have been studied by transmission electron microscopy.Modulated structures of all Bi-based superconducting phases are in b-c plane, therefore, it is the best way to determine modulated structure and c parameter in diffraction pattern. FIG. 1,2,3 show diffraction patterns of three kinds of modulations in Pb-doped ceramic samples. Energy dispersive X-ray analysis (EDAX) confirms the presence of Pb in the three modulated structures. Parameters c are 3 0.06, 38.29, 30.24Å, ie 2212, 2223, 2212 phases for FIG. 1,2,3 respectively. Their average space groups are all Bbmb.

Electron microscopy study of microtexture in Cu-Al-Ni shape memory alloys processed by powder metallurgy

2003 ◽  
Vol 112 ◽  
pp. 615-618 ◽  
Author(s):  
P. P. Rodriguez ◽  
J. San Jean ◽  
A. Iza-Mendia ◽  
V. Recarte ◽  
J. J. Pérez-Landazabal ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Powder Metallurgy ◽  
Shape Memory Alloys ◽  
Shape Memory ◽  
Microscopy Study ◽  
Electron Microscopy Study
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