PURPOSE: To evaluate the parameters of optic nerve head (ONH) and retinal nerve fiber layer (RNFL) in patients with large cup/disc ratio (CDR) and normal neuroretinal rim configuration who have normal perimetry (physiologic large cups, LC) and to compare these parameters with those of the normal and early glaucoma patients. METHODS: Using Heidelberg retinal tomography (HRT) and optical coherence tomography (OCT), 30 patients with LC, 29 normal subjects, and 31 early glaucoma patients were examined. One eye from each subject was randomly selected. RESULTS: Significant differences between LC and glaucomatous eyes (GE) were found in parameters indicating loss of nerve fibers, such as rim area, rim volume, and mean RNFL thickness. However, there was no difference between LC and normal eyes (NE) in RNFL thickness, rim area, and rim volume. LC was able to be defined as a normal central excavation with a large disc and large CDR with a normal rim area. CONCLUSIONS: HRT ONH parameters and RNFL thickness obtained with OCT may be useful for differentiating between glaucoma and LC eyes.
Retina/*pathology ; Optic Disk/*pathology ; Nerve Fibers/*pathology ; Middle Aged ; Humans ; Glaucoma/*pathology ; Adult ; Adolescent

Diseases and injuries to the nervous system can lead to a devastating chronic pain condition called neuropathic pain. We review changes that occur in the peripheral nervous system that may play a role in this disease. Common animal models for neuropathic pain involve an injury to one or more peripheral nerves. Following such an injury, the nerve fibers that have been injured exhibit many abnormal properties including the development of spontaneous neural activity as well as a change in the expression of certain genes in their cell body. Recent data indicate that adjacent, uninjured nerve fibers also exhibit significant changes. These changes are thought to be driven by injury-induced alterations in the milieu surrounding the uninjured nerve and nerve terminals. Thus, alteration in neural signaling in both injured and uninjured neurons play a role in the development of neuropathic pain after peripheral nerve injury.
Animals ; Disease Models, Animal ; Nerve Fibers ; pathology ; Neuralgia ; physiopathology ; Neurons, Afferent ; cytology ; Peripheral Nerve Injuries ; physiopathology

OBJECTIVETo observe the change of the muscular fiber phynotype at different condition of nerve injury.

METHODSRabbits were used as an animal model in this study. The trigeminus and facial nerves of the animal were simultaneously severed (group 1) or only the latter was severed (group 2). The morphologic change of the muscular fibers was observed with histochemical methods; the tension of contraction and the threshold value of electrical stimulation were observed with electrical physiological methods.

RESULTSTrigeminus nerve play an important role in delaying muscular atrophy after facial nerve was severed. The atrophy degree of type II a and II b muscular fibers was less in group 2 than that in group 1. The change of type 1 muscular fibers was not affected by trigeminus nerve. New muscular fibers emerged in group 2. The tension of contraction and the threshold value of electrical stimulation were better in group 2 than that of in group 1.

CONCLUSIONSSensory nerve could delay muscle atrophy after denervation. Sensory nerve should be repaired simultaneously when the motor nerve was sutured. The results of this study would facilitate clinical treatment for facial palsy.

Animals ; Denervation ; Disease Models, Animal ; Facial Nerve ; Facial Nerve Diseases ; pathology ; Female ; Muscle Fibers, Skeletal ; pathology ; Muscle Fibers, Slow-Twitch ; pathology ; Rabbits

Alzheimer Disease ; Diabetic Neuropathies ; pathology ; Glaucoma ; pathology ; Humans ; Multiple Sclerosis ; pathology ; Nerve Fibers ; pathology ; Ophthalmoscopy ; Optic Nerve ; pathology ; Parkinson Disease ; pathology ; Retinal Neurons ; pathology ; Tomography, Optical Coherence

Firing patterns of injured nerve fibers were recorded using the single-fiber firing recording technique. Under the same background firing pattern, three types of bursting were induced separately by EGTA, veratridine or high [Ca(2+)](o) in the same type of nerve fibers. The results suggest that different firing patterns are related to different stimuli, which means that each firing pattern carries corresponding neural information.
Action Potentials ; Animals ; Calcium ; pharmacology ; Egtazic Acid ; pharmacology ; Nerve Fibers ; drug effects ; pathology ; Rats ; Veratridine ; pharmacology

OBJECTIVE: To observe ultrastructure changes of electrical injury in rats. METHODS: An experimental model of rats suffered from the low voltage were designed. Ultrastructure changes of electrical injured tissues were observed under transmission electron microscope. RESULTS: (1) Plasma of epithelium was concreted in the affected areas and inner membrane system was broken. (2) Hypercontraction bands were observed in skeleton muscles. (3) There was dissolved necrosis and hypercontraction bands in the myocardium. (4) Vacuoles were found in plasma of endothelium of blood vessels on electrical current path, and myelin sheath of nerve fiber were loosed. CONCLUSION The above mentioned ultrastructure changes could be used as assistant diagnostic index of electrocution. The mechanism of the changes were discussed.
Animals ; Electric Injuries/pathology* ; Muscle, Skeletal/ultrastructure* ; Nerve Fibers/ultrastructure* ; Rats ; Rats, Sprague-Dawley

Spinal cord injury (SCI) is frequently companied by necrosis and apoptosis of oligodendrocytes (OLs), which contributes to demyelination of myelinated nerve fibers and their electrophysiological defects. This pathological demyelination often results in sensory or motor deficits. Here, we first focus on the microenvironment changes after SCI that cause OLs' death, then discuss the major mechanism of endogenous oligodendrocytogenesis and axonal remyelination, and finally summarize current therapies targeting OLs protection and replacement.
Animals ; Apoptosis ; physiology ; Cell Death ; physiology ; Humans ; Necrosis ; pathology ; Nerve Fibers, Myelinated ; pathology ; Nerve Regeneration ; physiology ; Oligodendroglia ; pathology ; Spinal Cord ; physiopathology ; Spinal Cord Injuries ; pathology ; physiopathology ; therapy

OBJECTIVETo observe the change in quantity and morphology of nerve fibers in different periods in granulation tissue in full-thickness burn wound.

METHODSThe granulation tissue samples were harvested from 40 patients with full-thickness burn in our unit at 1st, 2nd, 3rd and 4th post burn week (PBW), 10 samples were obtained at each time point. Donor site tissues from 10 burn patients were used as normal control. Immunofluorescent staining technique with anti-neurofilament (NF) monoclonal antibody was employed to examine the expression of nerve fibers in granulation tissue and normal skin. The morphology of nerve fibers was observed with fluorescence microscope and laser scanning confocal microscope.

RESULTSFluorescence microscopy showed: nerve fibers were short and rare at 1 PBW, the ratio of nerve fibers positive area was (0.14 +/- 0.08)%. Nerve fibers increased slightly and were in single filament without branches, and the positive area ratio of nerve fibers (0.40 +/- 0.09)% was much lower than that of normal control [(0.62 +/- 0.12)%, P < 0.05]. Nerve fibers increased significantly and were arranged like a mesh with more branches and sproutings, and the positive area ratio of nerve fibers was (0.73 +/- 0.16)% at 3 PBW. The quantity of nerve fibers at 4 PBW was similar to that of 3 PBW, and the positive area ratio of nerve fibers was (0.66 +/- 0.13)%. Observations under LSCM: the nerve fibers were short at 1, 2 PBW; was irregular at 3 PBW, among them some were swollen and distorted, and fragmentation and vacuolation were observed. They became aggregated at 4PBW with less branches, similar to that at 3 PBW. The structures of nerve fibers in normal control were intact, without obvious pathological changes.

CONCLUSIONThe change in quantity and morphology of nerve fibers in burn wound is related to the time of granulation tissue development.

Adult ; Burns ; pathology ; Female ; Fluorescent Antibody Technique ; Granuloma ; etiology ; pathology ; Humans ; Male ; Middle Aged ; Nerve Fibers ; metabolism ; pathology ; Nerve Regeneration ; Neurofilament Proteins ; immunology ; Skin ; innervation ; Wound Healing

A 59-year-old woman was referred to our clinic for a glaucoma evaluation. The visual acuity and intraocular pressure were normal in both eyes. However, red-free fundus photography in the left eye showed a superotemporal wedge-shaped retinal nerve fiber layer defect, and visual field testing showed a corresponding partial arcuate scotoma. In an optical coherence tomography examination, the macula was flat, but an arcuate-shaped peripapillary retinoschisis was found. Further, the retinoschisis seemed to be connected with a superotemporal optic pit shown in a disc photograph. After 3 months of a topical prostaglandin analogue medication, the intraocular pressure in the retinoschisis eye was lowered from 14 to 10 mmHg and the peripapillary retinoschisis was almost resolved. We report a rare case of an optic disc pit with peripapillary retinoschisis presenting as a localized retinal nerve fiber layer defect.
Female ; Humans ; Middle Aged ; Nerve Fibers/*pathology ; Optic Disk/*abnormalities/*pathology ; Optic Nerve Diseases/*diagnosis ; Retinal Ganglion Cells/*pathology ; Retinoschisis/*diagnosis/drug therapy ; Tomography, Optical Coherence

A quantitative assessment of the density of the protein gene product 9.5 (PGP9.5), the neural cell adhesion molecule (NCAM), and the low-affinity nerve growth factor receptor (NGFR) expressing nerve fibers in the circular muscle layer in the colon was carried out by morphometric analyses from 13 patients with Hirschsprung's disease (HD). The difference in the nerve fiber density between the ganglionic and aganglionic segments was compared by calculating the ratio of the sum of the areas occupied by positively stained nerve fibers per unit area of the muscle after immunohistochemical staining on paraffin embedded tissue sections using computer software. There was an obvious difference in the density of the PGP9.5 stained nerve fibers between the ganglionic (0.0380 +/- 0.0171) and aganglionic segments (0.0143 +/- 0.01661). The NCAM-positive nerve fibers were fewer in number than those of both the PGP9.5-positive fibers and NCAM-positive fibers, which were also markedly lower in number in the aganglionic segment (0.0066 +/- 0.0076) than in the ganglionic segment (0.0230 +/- 0.0195). Immunostaining for low-affinity NGFR revealed much fainter staining in the ganglionic and aganglionic segment without a statistically significant difference in their density. Considering the fact that PGP9.5 is a very sensitive marker for nerve fibers, the results of this study reaffirm the innervation failure of the proper muscle in HD. The decreased NCAM expression level in the aganglionic segment appears to be caused not by the selective down-regulation of NCAM expression among the nerve fibers but by a markedly reduced number of nerve fibers.
Colon/*innervation ; Hirschsprung Disease/*pathology ; Human ; Muscle, Smooth/*innervation ; Nerve Fibers/*chemistry/pathology ; Neural Cell Adhesion Molecules/*analysis ; Receptor, Nerve Growth Factor/analysis ; Thiolester Hydrolases/*analysis