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Granular Cell Layer (granular + cell_layer)
Selected AbstractsAbnormal Excitability of Hippocampal CA3 Neurons in Noda Epileptic Rat (NER): Alteration of Seizure with AgingEPILEPSIA, Issue 2000Ryosuke Hanaya Purpose: Noda epileptic rat (NER), a mutant found in thc colony of Crj:Wistar rats, spontaneously shows tonic-clonic convulsions approximately once every 30 hours from 8,16 weeks of age. A long-lasting dcpolarization shift accompanied by repetitivc firings are observed in hippocampal CA3 pyramidal neurons of NER with seizures. Using hippocampal slice preparations of NER, the present electrophysiologi- cal study was performed to elucidate whether this abnormal firing in CA3 neurons developed with age and if abnormality of Ca2+ channel was involved. Methods: Hippocampal slices (40Opm) werc prepared from NER and normal Wistar rats (age; 4,29 weeks). A single rectangular pulse stimulus composed of 0.1-ms duration was delivered to the mossy fibers every 5 seconds though a bipolar electrode placed in the granular cell layer of the dentate gyrus. Intracellular recording was made from the CA3 pyramidal cell using a microelectrode containing 3M KCI intracellular recordings. A Ca2+ spike was elicited by applying a depolarizing pulse (InA, 120ms) in the cell through the recording electrode under a blockadc of Na+ and K+ channels using 1 pM tetrodotoxin and I 0mM tctraethylammonium added to the artificial CSF, respectivcly. Nicardipine (I-IOOnM), a Ca2+ channel blocker, was applicd to the bath. Results: Thirty-seven slices from I9 NER and 6 slices from 4 normal Wishe rats were used. There were no obvious changes in the resting membrane potentials of CA3 neurons between NER and Wistar rats tested. When a single stimulus was delivered to the mossy fibers, a long-lasting depolarization shift accompanied by repetitive firings followed by after-hyperpolarization werc also obtained i n hippocampal CA3 neurons of young NER (4,5 weeks of age) before occurrence of any seizurcs, although the depolarization shift in younger NER was shorter than that in NER aged more than 6 weeks. These abnormal firings werc evokcd in 58% and 30% of all CA3 neurons tested in the younger and mature NER (6,1 5 weeks of age), respectively. Furthermore, abnormal firing was not elicited in NER aged after I6 weeks. Agc-matched Wistar rats showed only single action potentials without any depolarization shift with single mossy fiber stimulation. Bath application of nicardipine (IOnM) inhibited this long-lasting depolarization shift and the accompanying repetitive firing followed by afterhypcrpolarization without affecting the first spike induced by mossy fiber stimulations. Furthermore, nicai-dipine (IOnM) inhibited the Ca2+ spikes elicited by applying a depolarizing pulse in the neurons of NER with seizures, although a higher dose (100nM) did not affect those in Wistar rats. Conclusions: These findings indicate that abnormal excitability of the NER CA3 pyramidal neurons is probably due to abnormality in the Ca2+ channcls. The abnorinal excitability was observed in NER at an age when tonic-clonic convulsions were not detected, suggesting that thc hippocampus may probably scrve as an epileptogenic focus in younger NER and the seizure impulses originating i n this area are transinittcd to the new other seizurc foci in mature NER. [source] Nonmutilating palmoplantar and periorificial kertoderma: a variant of Olmsted syndrome or a distinct entity?INTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 6 2010Ahmad Nofal MD Background, Olmsted syndrome is a rare keratinization disorder characterized by mutilating palmoplantar and periorificial keratoderma as the two major diagnostic features. Some authors believe that atypical cases without this standard combination may not really belong to Olmsted syndrome. Herein, we describe two familial cases with congenital nonmutilating palmoplantar and periorificial keratoderma, and discuss their similarities and differences with Olmsted syndrome. Patients, The study included two sisters who presented with focal and punctate nonmutilating palmoplantar keratoderma (PPK), periorificial hyperkeratotic plaques, and widely distributed keratotic lesions. Fragile denuded areas of the skin were found in sites exposed to trauma. Fingernails showed a characteristic form of leukonychia. Results, Histopathology of plantar keratoderma showed psoriasiform hyperplasia with marked compact hyperkeratosis, while vicinity of denuded skin revealed thin parakeratotic zone and dissolution of the granular cell layer. Immunohistochemistry demonstrated suprabasal staining pattern for acidic keratin (AE1) and uniform positivity, starting four to six layers above the basal layer, for cytokeratin 10. Electron microscopy showed defective keratinization. Cytogenetic studies revealed normal karyotype and no chromosomal breakage. Conclusion, Our cases share Olmsted syndrome in the early onset, and the presence of symmetrical PPK, periorificial keratoderma and keratotic lesions. However, the striking nonmutilating nature of PPK and the presence of unique features in our patients suggest a newly described keratinization disorder. [source] Description of distributed features of the nestin-containing cells in brains of adult mice: A potential source of neural precursor cellsJOURNAL OF NEUROSCIENCE RESEARCH, Issue 5 2010Renshi Xu Abstract The distribution of neural precursor cells (NPCs) in adult mice brain has so far not been described. Therefore, we investigated the distribution of NPCs by analyzing the nestin-containing cells (NCCs) in distinct brain regions of adult nestin second-intron enhancer-controlled LacZ reporter transgenic mice through LacZ staining. Results showed that NCCs existed in various regions of adult mouse brain. In cerebellum, the greatest number of NCCs existed in cortex of the simple lobule, followed by cortex of the cerebellar lobule. In olfactory bulb, NCCs were most numerous in the granular cell layer, followed by the mitral cell layer and the internal plexiform, glomerular, and external plexiform layers. In brain nuclei (nu), NCCs were most numerous in the marginal nu, followed by the brainstem and diencephalon nu. NCCs in sensory nu of brainstem were more numerous than in motor nu, and NCCs in the dorsal of sensory nu were more numerous than in the ventral part. In brain ventricle systems, NCCs were largely distributed in the center of and external to the lateral ventricle, the inferior part of the third ventricle, the dorsal and inferior parts of the fourth ventricle, and the gray matter around the cerebral aqueduct. NCCs in the left vs. right brain were not significantly different. These data collectively indicate that NCCs were extensively distributed in the cerebellum and olfactory bulb, the partial nu of the marginal system, the partial brain nu adjacent to brain ventricle systems, the subependymal zone, and the cerebral cortex around the marginal lobe and were a potential source of NPCs. © 2009 Wiley-Liss, Inc. [source] Cerebellar cortical abiotrophy in Lagotto Romagnolo dogsJOURNAL OF SMALL ANIMAL PRACTICE, Issue 8 2007T. S. Jokinen This case report documents two pathological variations of potentially inherited, cerebellar cortical abiotrophy in two unrelated Lagotto Romagnolo breed dogs. The first dog had an atypical lesion in the cerebellar cortex with depletion of cerebellar granular cell layer and sparing of the Purkinje cell layer. The second case had degenerative changes in both Purkinje and granular cell layers. The clinical picture was similar in both cases presented, although the severity of the signs of cerebellar dysfunction varied. [source] Circumscribed palmar hypokeratosis: clinical evolution and ultrastructural study after prolonged treatment with topical calcipotriolJOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 4 2005F Urbina Abstract Circumscribed palmar hypokeratosis is a recently described condition that consists of a solitary area of depressed skin affecting the palm (or sole). Its histopathological features include a thinned horny layer, a slightly diminished granular cell layer, and intraepidermal vacuolated cells. Prolonged treatment with topical calcipotriol resulted in complete recovery of the affected zone in the case reported here. A second biopsy of the lesion taken at around the fourth year of therapy showed a normalization of the granular layer, a reduction in the intraepidermal vacuolated cells, and a somewhat thicker horny layer. An ultrastructural study carried out at the same time showed a reduction in keratin bundles and keratohyalin granules, and an increase in lipid droplets up to the horny layer. These findings and the therapeutic response to topical calcipotriol support the concept that circumscribed palmar hypokeratosis is a focalized abnormal keratinization defect morphologically expressed at the granular and horny layers. [source] Nerve growth factor ,/pro-nerve growth factor and their receptors in normal human oral mucosaEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 5 2007Katsuhiko Hayashi Nerve growth factor , (NGF- ,) and its precursor proNGF are important for the differentiation and survival of neurons and dermal keratinocytes. The aim of this study was to determine the role that NGF might play in the differentiation and wound healing of oral mucosa. Cultured normal human oral mucosal keratinocytes expressed mRNA for NGF- ,/proNGF and for their receptors TrkA and p75NTR. Lysates from cultured oral mucosal keratinocytes did not contain detectable amounts of mature 14-kDa NGF- , but did contain several NGF proforms with molecular weights between 32 and 114 kDa. Culture medium from oral mucosal keratinocytes contained 75 kDa proNGF. The addition of NGF- , significantly enhanced the proliferation of oral mucosal keratinocyte cultures and in vitro scratch closure. Immunostaining of biopsies from normal oral mucosa showed the presence of proNGF in all epithelial layers. NGF staining was observed in the granular and upper spinous cell layers. TrkA immunoreactivity was detected in basal and parabasal cells, with weak to moderate staining in spinous and granular cell layers. p75NTR staining was seen in basal cell layers. These findings indicate that NGF- ,/proNGF have mitogenic and motogenic effects on oral mucosal keratinocytes and therefore may aid in the healing of oral wounds. Differential expression of NGF and NGF receptors throughout the epithelium suggests a role in epithelial differentiation. [source] Immunization with a cannabinoid receptor type 1 peptide results in experimental allergic meningocerebellitis in the Lewis rat: A model for cell-mediated autoimmune neuropathology,JOURNAL OF NEUROSCIENCE RESEARCH, Issue 2 2002Margit G. Proescholdt Abstract Neuronal elements are increasingly suggested as primary targets of an autoimmune attack in certain neurological and neuropsychiatric diseases. Type 1 cannabinoid receptors (CB1) were selected as autoimmune targets because they are predominantly expressed on neuronal surfaces in brain and display strikingly high protein levels in striatum, hippocampus, and cerebellum. Female Lewis rats were immunized with N-terminally acetylated peptides (50 or 400 ,g per rat) of the extracellular domains of the rat CB1 and killed at various time points. Subsequent evaluation using immunohistochemistry and in situ hybridization showed dense infiltration of immune cells exclusively within the cerebellum, peaking 12,16 days after immunization with the CB1 peptide containing amino acids 9,25. The infiltrates clustered in meninges and perivascular locations in molecular and granular cell layers and were also scattered throughout the CB1-rich neuropil. They consisted primarily of CD4+ and ED1+ cells, suggestive of cell-mediated autoimmune pathology. There were no inflammatory infiltrates elsewhere in the brain or spinal cord. The results show that neuronal elements, such as neuronal cell-surface receptors, may be recognized as antigenic targets in a cell-mediated autoimmune attack and, therefore, support the hypothesis of cell-mediated antineuronal autoimmune pathology in certain brain disorders. Published 2002 Wiley-Liss, Inc. [source] Histomorphometric characteristics and expression of epidermal growth factor and its receptor by epithelial cells of normal gingiva and hereditary gingival fibromatosisJOURNAL OF PERIODONTAL RESEARCH, Issue 3 2003C. S. A. Araujo Objective:, The objective of this study was to examine the histomorphometric features and evaluate the expression of epidermal growth factor (EGF) and transmembranic receptor (EGFr) and the proliferative potential of epithelial cells from normal and hereditary gingival fibromatosis (HGF) gingival tissues. Background:, EGF is a multifunctional cytokine with a variety of biological effects including stimulation of cell proliferation by binding to its specific EGFr. Methods:, Immunohistochemistry was performed to measure EGF and EGFr expression and the epithelial cell proliferation was determined by measuring proliferating cell nuclear antigen (PCNA). Results:, Histomorphometric evaluation indicated that in HGF the mean height of the epithelial papillae was higher compared to the normal gingiva (NG), whereas mean epithelial area and number of epithelial papillae were quite similar in both groups. The EGF and EGFr positive cells were observed in the basal, spinous and granular cell layers of both normal and HGF tissues, with a gradual reduction from the basal layer. Although the expressions of EGF and EGFr in the control group were significantly higher than those from HGF, in HGF the epithelial papilla tips showed increased number of proliferating cells and elevated expression of EGF and EGFr. There was a correlation between the proliferative potential of epithelial cells and the expression of EGF or EGFr only in the epithelial papilla tips of HGF gingiva. Conclusion:, Our data suggest that EGF and EGFr in the oral epithelium of HGF gingiva may stimulate epithelial cell proliferation, with the resultant apical migration of the oral epithelium and formation of the slender deep epithelial papillae; however, without hyperplastic alterations. [source] Cerebellar cortical abiotrophy in Lagotto Romagnolo dogsJOURNAL OF SMALL ANIMAL PRACTICE, Issue 8 2007T. S. Jokinen This case report documents two pathological variations of potentially inherited, cerebellar cortical abiotrophy in two unrelated Lagotto Romagnolo breed dogs. The first dog had an atypical lesion in the cerebellar cortex with depletion of cerebellar granular cell layer and sparing of the Purkinje cell layer. The second case had degenerative changes in both Purkinje and granular cell layers. The clinical picture was similar in both cases presented, although the severity of the signs of cerebellar dysfunction varied. [source] Histological effects of tazarotene 0·1% cream vs. vehicle on photodamaged skin: a 6-month, multicentre, double-blind, randomized, vehicle-controlled study in patients with photodamaged facial skinBRITISH JOURNAL OF DERMATOLOGY, Issue 6 2004L.A. Machtinger Summary Background, Topical tazarotene has been shown to offer efficacy in ameliorating multiple effects of photodamage. Objectives, To evaluate the histological effects of tazarotene cream on photodamaged skin. Methods, In this multicentre, double-blind, randomized, vehicle-controlled study, 50 patients with photodamaged facial skin (at least mild fine wrinkling and mottled hyperpigmentation, with at least one of these being moderate) were randomized to apply tazarotene 0·1% cream or vehicle cream to their face, once daily for 24 weeks. Results, Blinded assessments showed that tazarotene was less likely than vehicle to be associated with an increase in keratinocytic and melanocytic atypia, and more likely than vehicle to be associated with a reduction in atypia. Between-group comparisons in distribution of change from baseline categories of severity were in favour of tazarotene (P = 0·055 for keratinocytic atypia, P = 0·034 for melanocytic atypia, and P < 0·001 for the number of granular cell layers). Compared with vehicle, tazarotene was associated with an increase in epidermal polarity (P = 0·008) and epidermal thickness (P = 0·012), and a tendency for stratum corneum compaction. Tazarotene was also associated with widened intercellular spaces (reported as epidermal oedema) relative to vehicle (P < 0·001). Conclusions, Treatment of photodamaged skin with tazarotene is associated with an amelioration of keratinocytic and melanocytic atypia, an improvement in epidermal polarity, and an increase in epidermal thickness. [source] | ||||||||||