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PubMed1977

Preparation of antisera to neurofilament protein from chicken brain and human sciatic nerve.

Antigens isolated by hydroxyapatite chromatography from human sciatic nerve (SN1 protein) and from 8 M urea extracts of chicken brain were selectively localized by immunofluorescence to neurofibrils in rat and chicken CNS. Absorption of the antisera with SN1 protein, chicken antigen or GFA protein abolished the staining. Antisera raised against antigen isolated with the same procedure from buffer extracts of chicken brain stained both neurofibrils and glial fibrils by immunofluorescence. Neurofibrillary staining was selectively abolished by absorption of the antisera with SN1 protein. Antisera prepared against axonal preparations isolated from bovine white matter only stained astroglia and were thus undistinguishable from anti-GFA sera in this respect. The data suggested that the protein subunits of neurofilament and glial filaments, although difficult to separate in brain extracts by standard biochemical procedures and by subcellular fractionation in bovine white matter, still retain immunological specificity. In addition, the immunological cross reactivity between human and chicken antigens suggested that neurofilaments, as other constituents of the cytoskeleton such as microtubules and actin microfilaments, show a high degree of evolutionary stability.

Animals↗
PubMed2005

Acetylcholinesterase in Hirschsprung's disease.

The association between the congenital absence of colonic ganglion cells and an increased acetylcholinesterase (AChE) expression in the affected tissue is of diagnostic importance in Hirschsprung's disease (HSCR). Investigation of AChE's function in development may also help unravel some of the complex pathophysiology in HSCR. Normal nerves do not stain for AChE, but increased AChE expression is associated with the hypertrophied extrinsic nerve fibres of the aganglionic segment in HSCR. Although a high degree of histochemical diagnostic accuracy exists, results are not always uniform, and false positives and false negatives are reported. False negative results are primarily related to age, and an absence of AChE reaction does not exclude HSCR in neonates within the first 3 weeks after birth. AChE staining results may lack uniformity, resulting in a number of technical modifications that have been made to improve standardization of AChE staining. At least two distinct histological patterns are described, types A and B. The interpretation of increased AChE staining patterns in ganglionated bowel at the time of surgical pull-through remains a problem in patients with HSCR. The development of rapid staining techniques has helped to identify normal ganglionated bowel with greater certainty. The presence of fine AChE neurofibrils in the ganglionated segment has contributed to the debate surrounding intestinal neuronal dysplasia. Quantitative assay of cholinesterase activity confirms the pattern of histochemical staining. AChE is particularly increased in relation to butrylcholinesterase, with one molecular form, the G4 tetrameric form, predominating. It is likely that the raised levels of AChE in aganglionic tissue are the transcriptional consequence of the abnormalities in signalling molecules that characterize HSCR. Evidence suggests that this AChE is functioning in a nonenzymatic capacity to promote cell adhesion and differentiation and that the hypertrophied nerves and neurofibrils may be the result of this increased AChE expression.

Acetylcholinesterase↗
PubMed2005

Neurotrophic effect of magnolol in the hippocampal CA1 region of senescence-accelerated mice (SAMP1).

Magnolol has neurotrophic effects in primary cultured rat cortical neurons, which are expressed as the promotion of neurite outgrowth and neuronal survival. In this study, we investigated the protective effect of magnolol against age-related neuronal loss in the hippocampus using senescence-accelerated mouse (SAMP1). Magnolol (5, 10 mg/kg) was orally administered once a day for 14 d to 2- or 4-month-old mice, and evaluation was carried out when the mice were 4 or 6 months old. The density of neurofibrils decreased with aging in the stratum radiatum of the CA1 region in the hippocampus of SAMP1, not SAMR1. Treatment with magnolol significantly prevented the decrease of neurofibrils in the CA1, when it was administered in 2-month-olds. However, administration at 4 months of age did not result in a preventive effect. These findings suggest that the administration of magnolol before the initiation of neuronal loss may result in a protective effect in the hippocampus.

Aging↗
PubMed1996

The mechanism of Bodian's silver staining: effect of copper ion on silver impregnation.

We studied the effect of the duration (0.5-48 h) of silver impregnation on the intensity of Bodian's silver staining using formalin-fixed, paraffin-embedded sections of a human brain. The silver ion (Ag+) and copper ion (Cu2+) in the silver protein solution were quantified simultaneously for treatments of various durations. Both the intensity of staining and the quantities of Ag+ and Cu2+ were greatly affected by the duration of silver impregnation. While the quantity of Ag+ considerably decreased during the first 4 h of impregnation, that of Cu2+ greatly increased. Only small changes were observed in both ions after 12 h. Neurofibrils or axons, and neurofibrillary tangles (NFTs) were clearly stained after 12-24 and 16-48 h of impregnation, respectively. Strong staining of these components was not observed for other durations of treatment. The amount of metallic copper in silver impregnation also affected both the intensity of staining and the quantities of Ag+ and Cu2+ in the silver protein solution. Ag+ and Cu2+ were also present in the gold trichloride acid solution in which the section was toned. These findings suggest that both Cu2+ derived from metallic copper and silver protein are deposited on sections during silver impregnation, that the amount of Cu2+ may determine the amount of silver protein deposited on the section, and that the reduced (metallic) form of silver and copper on the section may participate in gold toning. Thus, to achieve strong staining of a desired component, it is important to examine the conditions of silver impregnation (i.e. duration and amount of metallic copper). For strong staining of neurofibrils, axons and NFTs, optimal results are obtained by the addition of 5 g of metallic copper foil to 100 ml of 1% silver protein solution, and by 16-24 h of impregnation.

Aged↗
PubMed2002

Cajal's hypotheses on neurobiones and neurotropic factor match properties of microtubules and S-100 beta.

Cajal described both the morphology and plasticity of neurons. He summarized the structure of neurons as composed of membrane, protoplasm, Golgi apparatus, nucleus, spongioplasm and neurofibrils (cytoskeleton). He initially considered the cytoskeleton as absorbing excitation energy and forming a "conductive pathway in the protoplasm" within the neuron. Later, he viewed the neurofibrillary threads as independent, living entities and called them neurobiones. Cajal recognized neuroplasticity in development, memory, sleep, injury and dementia, as well as after exposure to cold and starvation. He noted cytoskeletal changes during these events. However, he did not causatively connect the plastic changes in neurons with the changes in cytoskeleton. Finally, Cajal proposed a theory of chemoaffinity in 1892, and modified his neurotropic theory over the next 40 years. Today we accept that changes in the cytoskeleton produce changes in neuronal morphology. The properties of the cytoskeleton and neurobione as described by Cajal are similar to those of microtubules. These long intraneuronal neurofibrils are polymers of the protein tubulin and, whilst not being living entities, are highly dynamic, sensitive to environmental stimuli, and stabilized by microtubule associated proteins (MAPs). Furthermore, Cajal was very specific in his characterization of the neurotropic factor derived from Schwann cells. Initially, he thought the chemicals attracted the axonal fibers, but later he wrote that the factor was not attractant but rather was involved in assimilation, growth and ramifications. The neurotropic hypothesis described by Cajal in Degeneration and Regeneration in the Nervous System is more similar to a neurite extension factor (NEF) than to a neurotrophic growth factor or specific chemoaffinity (attractant) molecule. S-100 beta is the major NEF found in PNS Schwann cells and CNS astroglial cells. In summary, the views of Cajal on neuroplasticity, its frequency and function, agree with the modern hypothesis of neuronal instability. This concept states that MAPs regulate microtubule stability by a S-100 beta sensitive phosphorylation processes. Serotonin, by acting on the astroglial 5-HT1A receptor, releases S-100 beta and regulates neuronal morphology and apoptosis. This neuronal-glial connection provides a fresh view for linking neuroplasticity, mental illness, and memory with changes in the cytoskeleton.

Animals↗
PubMed1983

Histopathology of eye, optic nerve and brain in a case of dominant optic atrophy.

Histopathology of eye, optic nerve and brain was performed in a patient with typical signs and symptoms of dominant optic atrophy. He belonged to a previously-reported family of 152 members in which optic atrophy was demonstrable in 14 persons, and probably present in a further 8 cases. In the eyes, fibrosis of the retinal ganglion cell layer and disc was found. Ultrastructural examination showed a few remaining cells in this layer, heavy fibrosis and in particular a highly condensed inner limiting membrane. The optic nerves, the optic chiasm and optic tracts showed an increased content of collagen tissue and a decreased number of neurofibrils and myelin sheaths. In the lateral geniculate body there was massive loss of ganglion cells, fibrillary gliosis and a great quantity of fine granular lipid in the cytoplasm of the ganglion cells. No changes in the calcarine cortex were observed. Examination of the intracranial part of both vestibulocochlear nerves showed a decreased number of neurofibrils and myelin sheaths. It is concluded that the histopathological changes of the visual system are similar to those in Leber's disease, but less pronounced. The study confirms earlier theories that dominant optic atrophy is a primary degeneration of the ganglion cell layer in the retina, with ascending optic atrophy.

Aged↗
PubMed1982

Protargol silver impregnation and neuronal selectivity. Light and electron microscopic observations.

The neuronal selectivity of protargol silver was determined in embedded and cultured nervous tissue by light (LM) and transmission electron microscopy (TEM). Ultrastructurally, silver (85-140 A in diameter) was found deposited in neuronal, but not glial, perikarya and cell processes. Usually, the silver grains were arranged in elongated arrays that were associated with electron-dense, strand-like structures that correspond to the 'neurofibrils' observed in LM; myelin sheaths, mitochondria, Nissl substance, Golgi bodies, synaptic vesicles, and endoplasmic reticulum could be excluded as the basis for neuronal argyrophilia. Unfortunately, the composition of these neurofibrils was obscure because of poor tissue preservation involved with proper impregnation, but they appeared to correspond to microtubules and neurofilaments. Neuronal structures containing a predominance of either organelle were impregnated with protargol. Nuclei and nucleoli of neuronal and nonneuronal cells were densely stained with silver as visualized with LM and TEM. Not every neuron was impregnated with protargol, but under conditions of improper fixation some of these neurons had an electron-dense cytoplasm which exhibited a definite affinity for silver. A discussion of protargol selectivity is also presented.

Animals↗
PubMed2004

Experimental study of the morphological and electromyographic characteristics of the most frequent iatrogenic lesions of the recurrent laryngeal nerves in thyroid surgery.

INTRODUCTION: Iatrogenic lesions of the recurrent laryngeal nerves remain one of the most severe and frequent complications in thyroid surgery. According to Eisele (Laryngoscope 1996;106:443) their incidence varies between 1% and 12% depending on the size of surgery. AIM: The aim of the study was to examine experimentally the type of neural lesion and the efficiency of stimulation electromyography for immediate evaluation of the recurrent laryngeal nerve function in the most common surgical traumas. MATERIAL AND METHODS: Ten clinically healthy and parasite-free male dogs of mixed breed weighing from 11 to 18 kg were used in the experiment. The injured laryngeal nerves of the experimental animals were examined histologically using Sudan III staining for myelin and Bilshovsky staining for neurofibrils. The intraoperative electromyography was performed with Neurostim 100. RESULTS: The results show severe damage both of the myelin sheath and neurofibrils in most of the surgical traumas of the nerve fiber. The electromyography of the laryngeal musculature shows complete interruption of the conduction of the action potential in all types of experimental lesions. CONCLUSION: EMG intraoperative monitoring of the laryngeal nerves appears the most effective measure to avoid the complication.

Animals↗
PubMed2004

[Experimental and clinical study on functional restoration of the penis with large partial defect].

OBJECTIVE: To investigate the effective restoration method in penile partial defect. METHODS: To measure the thickness of suspensory ligaments on cadavers; To find the relationship between inferior pubic ramus and corpora cavernosa crus through corpora cavernosa angiography and ultrasonic scanning. The procedure of restoration was based on the use of dissection of the suspensory ligaments and part of crus, and the local fat flap had been transferred to fill the front space of symphysis ossium pubi. Various flaps were designed as coverage material. Penis residual stump was advanced to anterior portion of the newly restoration penile body as "glans"; To take full layer skin of penis from post-operating patients to observe neurofibril regeneration by light microscopy, electron microscopy and scanning electron microscopy; To determine sensation recovery by physical examination; To check erectile function with NEVA System. RESULTS: The whole suspensory ligaments thickness was 7.66 cm in average on 30 cadavers (60 sides). The crus were attached to bilateral inferior pubic ramus respectively, and distal reached the middle of inferior pubic ramus by corpora cavernosa angiography. In 14 health men by ultrasonic scanning, 6.60 cm in average from root of external penis to location of deep artery penis entered corpora cavernosa. Forty patients had been operated with the above methods. In the cases, the length of the penis varied from 0.5-4.0 cm in the flaccid, 2.0-6.0 cm in erect state before operation to 5.0-8.5 cm in the flaccid, 7.0-12.5 cm in erect state after operation. Twenty-eight cases had been followed up for more than one year, and 23 patients married with acceptable sexual life, eighteen men had successfully produced their next generations. The regenerative neurofibril could be seen under light microscope, immunohistochemistry marker, scanning and transmission electron microscope. The penis presented normal pain and touch feeling in the post-operating cases. The results showed that there was similar erectile ability of a normal male in the follow-up patients. CONCLUSION: With these basic and clinical researches, the restoration of penis tends to have a better appearance and function. It's a more optimal method compared with conventional procedures. The results have also provided valuable data for further study in related fields.

Adult↗
PubMed1985

Expression of microtubule-associated proteins, MAP-1 and MAP-2, in human neuroblastomas and differential diagnosis of immature neuroblasts.

The expression of microtubule-associated proteins, MAP-1 and MAP-2, was studied in human neuroblastomas at various developmental stages using the immuno-alkaline-phosphatase technique and immunofluorescence microscopy. Of 15 cases examined, including grade I, grade II, and grade III neuroblastomas (M. Hughes, H. B. Marsden, and M. K. Palmer, Cancer 34:1706, 1974), rabbit antibodies raised against individual MAP-1 and MAP-2 from mammalian brain showed strong reactions with the whole spectrum of tumor cells including the immature small neuroblasts, partially mature neuroblasts, neurofibrils, and ganglion cells. Antibodies to alpha- and beta-tubulin showed similar staining patterns. In contrast, antibodies to the Mr = 200.000 neurofilament protein were reactive only with the mature and partially mature tumor cells, as well as with neurofibrils, but not with immature "round-cell" neuroblasts. Other types of round-cell tumors examined, including several cases of Ewing's sarcoma, undifferentiated rhabdomyosarcoma, and malignant lymphoma, showed no reaction with antibodies to MAP-1 and MAP-2. These tumors were reactive, however, with antibodies to various other tumor-specific as well as nonspecific antigens. It is concluded that antibodies to neuronal MAPs provide a valuable new tool for the differential diagnosis of neuroblastomas.

Adolescent↗
PubMed1985

[Melanoma of ganglion cells arising from a thoracic sympathetic ganglion in an adult--a case report].

One case of pigmented tumor arising from the thoracic sympathetic ganglion in a 33 years old man is reported. By microscopy, the tumor cells were arranged in nests, among which ganglionic cells were observed. By Masson-Fontana and Lillie's stain, the pigment in the tumor cells was positive for melanin. By Glees-Marsland's stain, neurofibrils were demonstrated in the cytoplasm of some tumor cells. The presence of melanin and neurofibrils in the tumor cells and the interstitium proves that the tumor is a real melanocytic one arising from the sympathetic ganglion and that both the ganglionic and melanocytic cells originate from the neural crest. The malignancy of this tumor was also evidenced by the rapid extensive metastases occurring half a month after the operation.

Adult↗
PubMed1988

Alzheimer's disease: a new evidence for common epitopes between microtubule associated protein Tau and paired helical filaments (PHF): demonstration at the electron microscope level by a double immunogold labelling.

Paired helical filaments (PHF) are neuronal landmarks of Alzheimer's disease. These pathological filaments are antigenically related to proteins present in the normal cytoskeleton, particularly to microtubule associated protein Tau. The evidence for these common epitopes was studied on sections of cortex from Alzheimer brains after Araldite embedding. Two rabbit immune sera were used: one was raised against PHF isolated from Alzheimer cortex; the other against Tau proteins extracted from bovine cortex. The comparison of adjacent semi-thin sections alternatively treated with anti-PHF and anti-Tau immune sera reveals that both stained degenerating neurofibrils in pyramidal perikarya and in neurites surrounding senile plaques. On ultra-thin sections, double immunogold labelling of PHF was obtained. These results are in accordance with the hypothesis that Tau proteins are major antigenic components of PHF.

Alzheimer Disease↗
PubMed1995

Expression of neurofilament proteins by horizontal cells in the rabbit retina varies with retinal location.

Classical neurofibrillar staining methods and immunocytochemistry with antibodies to the light, medium and heavy chain subunits of the neurofilament triplet have been used for in situ and in vitro investigation of the organization of neurofilaments in A- and B-type horizontal cells of the adult rabbit retina. Surprisingly, their expression and organization within a cell is dependent on its location along the dorso-ventral axis of the retina. A-type horizontal cells in superior retina consistently stained with a wide variety of neurofibrillar methods to reveal neurofibrillar bundles, which immunocytochemistry showed to contain all three neurofilament subunits. A-type horizontal cells in inferior retina were uniformly refractory to neurofibrillar staining, although they expressed all three subunits. However, there was less of the light and medium subunits; the organization of the filaments into bundles (neurofibrils) is minimal. B-type horizontal cells could not be stained with any neurofibrillar method and were not recognizable by in situ immunocytochemistry. However, B-type cells could be seen to express all three subunits in vitro, but the expression of the light and medium subunits was weak. There was only a slight difference between B-type cells taken from superior and inferior retina. Combined with the results of recent transfection studies, these findings suggest that the amount of the light neurofilament subunit present in a horizontal cell determines its content of neurofibrillar bundles, and that rabbit horizontal cells may contain more neurofilament protein, particularly of the heavy subunit, than is used for neurofilament formation.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1975

Neurofilament and glycogen changes during cold acclimation in the trochlear nucleus of lizards (Sceloporus undulatus).

In lizards (Sceloporus undulatus), long term (13 or 19 weeks) acclimation to an environment of 6 degrees C produces a striking increase in the argyrophilic neurofibrillar network in most large perikarya of the trochlear nucleus. In electron micrographs the cells contain numerous bundles of 10-30 regularly-spaced 90 A neurofilaments. In the cells from warm acclimated animals, a plexus of neurofibrils is seen by light microscopy. The electron micrographs show scattered neurofilaments and fewer, thinner bundles than in the cold. Within the cell bodies of the cold animals, glycogen particles are organized in regional accumulations from which other organelles are excluded except for the bundles of neurofilaments which are distributed throughout the cytoplasm. The aggregations of rough endoplasmic reticulum (RER) are also penetrated by the neurofilament bundles. The increased neurofilamentous network in the cold is not accompanied by obvious changes in the amount or distribution of RER or of microtubules which are present in limited numbers in both conditions. The dendrites of trochlear cells and axon terminals within the nucleus also show a cold induced increase in neurofilaments, as well as in the distinctive accumulations of glycogen particles.

Acclimatization↗
PubMed1979

Neurofibrillary pathology: current status and research perspectives.

The neurofibrils seen in the light microscope are shown, by electron microscopy, to be heterogeneous structures, formed of neurotubules and neurofilaments. A variety of pathological conditions (especially, presenile and senile dementia (are characterized by the presence of neurofibrillary tangles, formed either of paired helical filaments or of single filaments. The morphology, distribution and biochemistry of these various fibrillary structures is reviewed. Particular attention is devoted to the assembly of neurotubules, to the mechanism of action of drugs which prevent assembly, and to possible implications for the experimental induction of neurofibrillary pathology. Of central importance in the arguments is the emphasis on the normal neurofibrillary structures being single forms of pleomorphic proteins. The healthy neuron assembles these proteins into the required form as is necessary for the needs of that neuron. Interference with this process in neuronal cell biology may lead to the deposition of neurofibrillary tangles. On the basis of the morphological and biochemical evidence, several approaches to the experimental study of neurofibrillary pathology are proposed.

Aging↗
PubMed1982

Neurotypy: regional individuality in rat brain detected by immunocytochemistry with monoclonal antibodies.

Hybridomas from spleen cell fusions of six BALB/c mice immunized with hypothalamus were analyzed by immunocytochemistry for antibodies reactive with paraffin sections of fixed rat brain. In a total of 135 antibody producers, 60% were brain specific. Among these, 54% reacted with glial elements, pituitary cells, or basal lamina of intracerebral capillaries, with little variation among individual hybridomas in each of these groups. Forty-six percent of brain-specific antibodies reacted with neuronal structures, localizing on nerve fibers, neurofibrils, or perikarya. Neuron-specific hybridomas could be classified into groups that localized in anatomically defineable overall patterns. Within these patterns individual hybridomas exhibited extensive qualitative localization diversity ("neurotypy"). Conceivably, the genetic message for a common "proantigen" within an overall pattern may be slightly modified during differentiation of a neuron, thus leading to minor variability in antigenic expression. During antibody formation, similar minor changes occur in the differentiation of the genetic message for the antibody variable region. Apparently, minor changes in the antibody combining site among groups of hybridomas is reflected in the detectability of minor neurotypic changes among differentiated neuronal proantigens. If neurotypy proves to be the result of single-base substitutions or of variability in alignment of peptide-coding exons, the Scharrer concept of the fundamental significance of neurosecretion could also become applicable to neuronal specialization.

Animals↗
PubMed1980

Presence of ganglion cells in Wilm's tumours: a review of the possible neuroepithelial origin of nephroblastoma.

Twenty-seven cases of Wilms' tumour were reviewed in order to confirm the presence of nervous tissue which could imply a 'neuroepithelial' origin for these neoplasms. For this purpose a double-silver impregnation technique was used. Groups of ganglion cells with neurofibrils and non-myelinated axon-like processes appeared associated with a fine neurofibrillar network with neuromuscular junctions. Nervous tissue in nephroblastoma is mature and should not be confused with primary ganglioneuroblastoma of the kidney in which neuroblasts in rosette-like groupings are very numerous. A case report of such a lesion is discussed for purposes of comparison.

Axons↗
PubMed1979

Recent advances of high voltage electron microscopy in biology.

Recent advances in the understanding of the structure of biological material made possible by the high voltage electron microscope are reviewed by briefly summarizing some of the more important results obtained in the past few years. The examination of thick sections of selectively stained specimens has continued to be the most widely used approach and has yielded information on the three-dimensional organization of a range of organelles, including the Golgi apparatus, neurofibrils and the transverse tubular system of striated muscle. The alternative method of studying intact cells prepared by critical-point drying is becoming increasingly popular, and has already made a significant contribution in demonstrating the microtrabecular systems within the cytoplasm of cultured cells.

Animals↗