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Objectives: DNA methylation is an important mechanism of gene control expression, and it has been poorly addressed in odontogenic tumours. On this basis, we aimed to assess the methylation pattern of 22 apoptosis-related genes in solid ameloblastomas., Materials and Methods: Ameloblastoma fresh samples (n = 10) and dental follicles (n = 8) were included in the study. The percentage fraction of methylated and unmethylated DNA promoter of 22 apoptosis-related genes was determined using enzymatic restriction digestion and quantitative real-time PCR (qPCR) array. The relative expressions of the genes that showed the most discrepant methylation profile between tumours and controls were analysed by reverse-transcription quantitative PCR (RT-qPCR)., Results: Lower methylation percentages of TNFRSF25 (47.2%) and BCL2L11 (33.2%) were observed in ameloblastomas compared with dental follicles (79.3% and 59.5%, respectively). The RT-qPCR analysis showed increased expression of BCL2L11 in ameloblastomas compared with dental follicles, in agreement with the methylation analysis results, while there was no difference between the expression levels of TNFRSF25 between both groups., Conclusions: On the basis of our results, the transcription of the apoptosis-related gene BCL2L11 is possibly regulated by promoter DNA methylation in ameloblastoma. The biological significance of this finding in ameloblastoma pathobiology remains to be clarified., (© 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Background: The amalgam-associated oral lichenoid lesion (AAOLL) shows clinical and histopathological features similar to oral lichen planus (OLP). Molecular researches to improve knowledge of pathogenesis and clinical behavior of AAOLL are still scarce., Objective: We investigated for the first time the use of loss of heterozygosity (LOH) as a molecular approach for genetic characterization of AAOLL in comparison with OLP and evaluated the cell proliferation index., Materials and Methods: The sample comprised nine AAOLLs, 10 OLPs, and eight NOMs matched by patients' gender and age. LOH was assessed using polymorphic microsatellite markers at chromosomes 9p (D9S157, D9S162, D9S171), 11q (D11S1369), and 17p (TP53, AFM238WF2). Cell proliferation was assessed by immunohistochemical expression of Ki-67 (MIB-1). The association between LOH and Ki-67 was investigated., Results: Loss of heterozygosity occurred in 5/9 AAOLLs and in 2/10 OLPs in at least one marker each, while NOM showed no LOH. Cell proliferation index in AAOLL ranged from 2 to 23%. There was no association between cell proliferation and LOH, independent of the marker., Conclusion: Our study shows that the profile of molecular changes in AAOLL and OLP, evaluated by LOH and Ki-67 expression, is similar. Additional studies including larger samples should be performed to confirm or to refute our findings., (© 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Brain ischemic tolerance is an endogenous protective mechanism activated by a preconditioning stimulus that is closely related to N-methyl-d-aspartate receptor (NMDAR). Glycine transporter type 1 (GlyT-1) inhibitors potentiate NMDAR and suggest an alternative strategy for brain preconditioning. The aim of this work was to evaluate the effects of brain preconditioning induced by sarcosine, a GlyT-1 inhibitor, against global cerebral ischemia and its relation to NMDAR. Sarcosine was administered over 7 days (300 or 500 mg/kg/day, ip) before the induction of a global cerebral ischemia model in Wistar rats (male, 8-week-old). It was observed that sarcosine preconditioning reduced cell death in rat hippocampi submitted to cerebral ischemia. Hippocampal levels of glycine were decreased in sarcosine-treated animals, which was associated with a reduction of [(3)H] glycine uptake and a decrease in glycine transporter expression (GlyT-1 and GlyT-2). The expression of glycine receptors and the NR1 and NR2A subunits of NMDAR were not affected by sarcosine preconditioning. However, sarcosine preconditioning reduced the expression of the NR2B subunits of NMDAR. In conclusion, these data demonstrate that sarcosine preconditioning induces ischemic tolerance against global cerebral ischemia and this neuroprotective state is associated with changes in glycine transport and reduction of NR2B-containing NMDAR expression., (Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.)

This study evaluated 724 primary head and neck squamous cell carcinoma (HNSCC) in young and old patients, with regard to clinical profile and immunohistochemical expression of p53 protein. Associations among age, epidemiological and clinicopathological parameters, and survival analysis were evaluated. HNSCC in young people occurred in 14.5% (median age 40.7years; male-to-female ratio 5.9:1). A statistical association was demonstrated between age and family history of cancer, and between age and anatomical site. Among older patients, a higher presence of disease was noted in posterior sites. Expression of p53 was found in 71.7% of the samples and a higher expression was noted in lesions of young patients. Survival analysis showed that the age parameter is not a reliable prognostic factor for HNSCC. Among young patients, cervical metastasis was associated with worse survival. The presence of a family history of cancer in young patients could indicate genetic susceptibility and molecular disturbances in the p53 pathway in HNSCC of young and older patients seem to be distinct.

Introduction: The aim of this study was to compare the morphological features of processus vaginalis (PV) and hernia sacs obtained from boys with undescended testis and inguinal hernia, respectively, in order to investigate whether these structures have similar histology., Material and Methods: Samples of PV (n=61) and hernia sacs (n=68) obtained from boys operated for undescended testis (n=58) and inguinal hernia (n=64), respectively, were stained with hematoxylin-eosin for optical qualitative microscopy analysis. The histological structures of each group of samples were compared by a pathologist blinded to the specific pathology., Results: The most prevalent histological findings were connective tissue, smooth muscle, mesothelium, nervous elements, striated muscle and mesonephric remnants with no statistical differences between the groups. The amount of smooth muscle was greater in the hernia sac group where it appeared as a layer. In contrast, the smooth muscle present in the form of sparse bundles around the connective tissue in the PV., Conclusions: Sacs obtained from boys with inguinal hernia and PV obtained from boys with undescended testis shares a similar histology except for the amount of smooth muscle when analyzed qualitatively by optical microscopy using hematoxylin-eosin stain.

Background: Inhaled anaesthetics (IAs) produce multiple dose-dependent behavioural effects including amnesia, hypnosis, and immobility in response to painful stimuli that are mediated by distinct anatomical, cellular, and molecular mechanisms. Amnesia is produced at lower anaesthetic concentrations compared with hypnosis or immobility. Nicotinic acetylcholine receptors (nAChRs) modulate hippocampal neural network correlates of memory and are highly sensitive to IAs. Activation of hippocampal nAChRs stimulates the release of norepinephrine (NE), a neurotransmitter implicated in modulating hippocampal synaptic plasticity. We tested the hypothesis that IAs disrupt hippocampal synaptic mechanisms critical to memory by determining the effects of isoflurane on NE release from hippocampal nerve terminals., Methods: Isolated nerve terminals prepared from adult male Sprague-Dawley rat hippocampus were radiolabelled with [(3)H]NE and either [(14)C]GABA or [(14)C]glutamate and superfused at 37 degrees C. Release evoked by a 2 min pulse of 100 microM nicotine or 5 microM 4-aminopyridine was evaluated in the presence or absence of isoflurane and/or selective antagonists., Results: Nicotine-evoked NE release from rat hippocampal nerve terminals was nAChR- and Ca(2+)-dependent, involved both alpha7 and non-alpha7 subunit-containing nAChRs, and was partially dependent on voltage-gated Na(+) channel activation based on sensitivities to various antagonists. Isoflurane inhibited nicotine-evoked NE release (IC(50)=0.18 mM) more potently than depolarization-evoked NE release (IC(50)=0.27 mM, P=0.014), consistent with distinct presynaptic mechanisms of IA action., Conclusions: Inhibition of hippocampal nAChR-dependent NE release by subanaesthetic concentrations of isoflurane supports a role in IA-induced amnesia.

Aim: To investigate the accuracy of histological diagnosis of oral hemangioma, oral vascular malformation and oral pyogenic granuloma according to immunohistochemical evaluation of the human erythrocyte-type glucose transporter protein (GLUT-1), and to observe the immunoexpression of this protein in oral varix., Materials and Methods: Immunohistochemistry for GLUT-1 was performed in 93 histologically diagnosed cases of oral benign vascular lesions: 17 vascular malformations, 19 hemangiomas, nine varix, and 48 pyogenic granulomas. Descriptive analyses were performed., Results: None of the cases of the oral benign vascular lesions evaluated were immunopositive to GLUT-1. The 19 cases histologically diagnosed as oral hemangioma that showed negative staining to GLUT-1 were reclassified as oral pyogenic granuloma or oral vascular malformations. The histological evaluation itself is not enough to obtain the correct diagnosis of oral HEM as none of the sample cases were true hemangioma. All sample cases with initial vascular malformation or pyogenic granulomas classification were negative to GLUT-1, demonstrating the accuracy of histological diagnosis of these lesions itself. Oral varix showed negative staining to GLUT-1 in blood vessels., Conclusions: GLUT-1 is an useful, effective and important auxiliary marker for the diagnosis of oral benign vascular lesions., Clinical Relevance: This study showed that histological diagnosis alone is not sufficient to correct diagnoses of oral hemangioma. Moreover, immunohistochemistry to GLUT-1 is a useful and easy diagnostic method that may be used to avoid such misdiagnosis. Accurate diagnosis of these oral lesions has an important clinical relevance allowing: (1) correct management, (2) adequate communication among the multidisciplinary team (dentist, dermatologist, pediatrist, radiologist, pathologist, and surgeon), (3) understanding of the biological behavior of the lesions, and (4) facilitate the development of new therapeutic modalities. Thus, supporting the use of this marker in medical and dentistry communities is warranted.

Ameloblastin (AMBN, MIM *601259) gene expresses an important protein (AMBN), present in the organic matrix of enamel. The AMBN protein has an important role in the differentiation of ameloblast cells and epithelium-mesenchyme signaling during odontogenesis which prompted us to investigate this gene in aggressive epithelial odontogenic tumors, such as ameloblastomas, and in some non-aggressive ones, such as the adenomatoid odontogenic tumor and the squamous odontogenic tumor. Six cases of epithelial odontogenic tumors were studied and normal cells of the patient's mucosa were used as negative controls. The results demonstrated novel mutations in all tumors, while mucosal cells showed the wild type DNA sequence. Our data demonstrates that AMBN gene has an important role in the tumorigenesis of subtypes of epithelial odontogenic tumors and that this phenotypic heterogeneity could be caused by genetic heterogeneity.

Fibrous dysplasia is a benign fibro-osseous disease of bone and its etiology has been previously established. Activating mutations in the gene that encodes the alpha subunit of stimulatory G protein (G(S)alpha) has been described in monostotic and polyostotic fibrous dysplasia and in the McCune-Albright syndrome. The present report describes a patient with monostotic fibrous dysplasia which diagnosis was confirmed by sequencing of the G(S)alpha gene, demonstrating a heterozygous missense mutation on codon 201 (201C --> T). Due to the high prevalence of G(S)alpha gene mutations in fibrous dysplasia in contrast to other benign and malignant fibrous-osseous lesions, mutational analysis are an additional and helpful parameter for the diagnosis of fibrous dysplasia in selected cases.

The aim of the present study was to evaluate the clinical, radiographic and histological characteristics of idiopathic bone cavities from the Oral Pathology archives at Universidade Federal de Minas Gerais. Forty-three cases were retrieved. Age, sex, some radiographic variables and morphological variables measured of the connective tissue, were studied. The results showed the men who developed cavities tended to be younger than women (median 16 years (range 11-48) compared with 18 (12-64)). Radiographically rounded lesions that were single, unilocular, and small were more common in younger patients. While rounded cavities occurred mainly in the anterior region, cavities with interdental scalloping occurred in the posterior area. The median age of the patients with thin connective tissue on the wall of the bony cavity was lower than that of those with a thicker lining. In conclusion, the present study shows that there is a significant relation between age and sex, radiographic and histological variables. These findings may contribute to the diagnosis of idiopathic bone cavities.

We report a rare case of periodontal myiasis by New World screwworm Cochliomyia hominivorax, an obligatory larval parasite, in a 66-year-old woman. The myiasis occurred in the anterior upper jaw associated with a pre-existent generalised periodontitis. About 40 larvae were removed from the lesion. One week later the periodontal tissues were healing normally and the patient was referred to a periodontist. As all of the larvae were in the last stage, they were probably deposited 5-7 days before.

In this paper, the effect of the alpha-scorpion toxin tityustoxin (TsTX) in the release of gamma-[(3)H]aminobutyric acid ([(3)H]GABA) from rat brain cortical slices is described. The TsTX-stimulatory effect on the release of [(3)H]GABA was dependent on incubation time and TsTX concentration, having an EC(50) of 0.33 microM. Tetrodotoxin (TTX) completely inhibited the TsTX action on [(3)H]GABA release. The scorpion toxin effect was calcium-dependent and involves P/Q calcium channels. beta-Alanine also induces the release of [(3)H]GABA that was not inhibited by TTX but was additive in the presence of TsTX. The data suggest a neuronal origin for the release of [(3)H]GABA by TsTX.

Protein kinase C (PKC) is a signal transducing enzyme that is an important regulator of multiple physiologic processes and a potential molecular target for volatile anaesthetic actions. However, the effects of these agents on PKC activity are not yet fully understood. Volatile anaesthetics increase intracellular calcium concentration ([Ca(2+)](i)) in a variety of cells, thus their effects on PKC activity may be indirect due to [Ca(2+)](i) increase. Alternatively, the anaesthetics could directly stimulate PKC activity. In order to distinguish these two possibilities in intact cells, we used a fully functional green fluorescent protein conjugated PKCbetaII (GFP-PKCbetaII) and confocal microscopy to evaluate the dynamic redistribution of PKC in living SN56 cells, a cholinergic cell line, in response to halothane. Halothane induced PKC translocation in SN56 cells transfected with GFP-PKCbetaII. This effect was not suppressed by dantrolene, a drug that blocks halothane-induced Ca(2+) release from intracellular stores in these cells. These findings indicate that halothane induces PKC translocation in SN56 cells independently of its ability to release calcium from internal stores., (Copyright 2002 Elsevier Science Inc.)

We describe an 8-year-old boy who presented with severe facial swelling. This progressed rapidly and 17 months later he died of gastrointestinal and pulmonary infections. The diagnosis was initially brown tumour associated with hyperparathyroidism, but this was revised in the light of laboratory investigations that were within the reference ranges, and normal appearance of the parathyroids on exploration to that of an extreme case of cherubism that behaved in a locally aggressive manner., (Copyright 2002 The British Association of Oral and Maxillofacial Surgeons.)

The effect of the beta-scorpion toxin, TiTX gamma on the release of [3H]GABA from rat brain cortical slices is described. The stimulatory effect of TiTX gamma on the release of [3H]GABA was dependent on incubation time and TiTX gamma concentration with an EC50 of 0.19 microM. The scorpion toxin effect was calcium dependent and was completely inhibited by tetrodotoxin. beta-Alanine also induced the release of [3H]GABA and this effect was not inhibited by tetrodotoxin but was additive in the presence of TiTX gamma. The data suggest a neuronal origin for the release of [3H]GABA by TiTX gamma.

Objective: This study was conducted to compare the survival rates of bone marrow transplantation (BMT) patients who were affected with the survival rates of those who were not affected by oral recrudescent human herpes virus-1 infection (HHV-1) after transplantation., Study Design: Fifty-two consecutive patients who underwent BMT were included in the study. The time of death after BMT was displayed, by means of the Kaplan-Meier method, for the following parameters: age and gender of the patient, donor gender, primary disease, stem cells, conditioning regimen, platelet number after day 100, acute and chronic graft-versus-host disease, oral recurrent HHV-1 infection post-BMT, oral lichenoid lesions of graft-versus-host disease, graft-versus-host disease at the salivary glands, parenteral nutrition, and oral mucositis. The data were initially analyzed by means of the log-rank test and then included in the Cox proportional hazards model., Results: The multivariate analysis demonstrated a significance of 5% for only the platelet numbers and oral recurrent HHV-1 infection., Conclusion: The present study provides evidence that platelet numbers below 100,000 cells/mm(3) after day 100 and oral recurrent HHV-1 infection are independent negative prognostic variables in BMT patients' 24-month survival rates.

Juvenile xanthogranuloma (JXG) is a dermatological condition of unknown etiology that rarely affects the oral mucosa. There are conflicting reports suggesting that it may represent a reactive virally-induced lesion associated with cytomegalovirus (CMV) infection. The present paper reports an additional case of oral JXG and discusses its possible association with CMV infection. The biotin-streptavidin system was used to detect early and late CMV antigens. Positive immunolabelling for both antigens was demonstrated in some histiocytes in the lesion. These findings suggest that JXG may be associated with CMV infection.

Objective: The purpose of the present study was to evaluate the relationship between histological epithelial dysplasia, the immunolocalization of p53 and glutathione S-transferase pi on the immunolocalization of the CD57 antigen., Materials and Methods: Seventy biopsies were included in the study and the streptavidin-biotin-peroxidase method was used to detect the antigens., Results: The results demonstrated a significant relationship between p53, GST-pi positive staining with moderate/severe epithelial dysplasia. There was no relationship between p53 and GST-pi. The mean number of CD57+ lymphoid cells was higher in the lesions with increased epithelial dysplasia and positive for GST-pi. No difference was found regarding CD57 immunolocalization in leukoplakias positive and negative for p53., Conclusions: As the presence of CD57+ lymphoid cells are indicative of immunosuppression, our study suggests that the severity of epithelial dysplasia and positive immunolabelling for GST-pi are associated with local immune response alterations in oral leukoplakias. Our data also give support to the idea that GST-pi and p53 are not time-point related during oral cancer development.

Cervicofacial actinomycosis in children is a rare disorder. This article reports a case in a 7-year-old-girl. The importance of cervicofacial actinomycosis in the differential diagnosis of cervical masses in young patients is emphasized.

Congenital absence of the salivary glands and lacrimal puncta is a rare autosomal-dominant disorder with variable expressivity. Only a few instances of this condition have been reported. We present the first Brazilian observation of this syndrome and a review of the literature., (Copyright 2000 Wiley-Liss, Inc.)

Cysticercosis is a condition in which a human acts as the intermediate host of the pork tapeworm Taenia solium. Although cysticercosis is a common disease in some regions of the world and can occur in any body site, oral lesions are rare. This paper reviews the natural history of the disease and reports on seven cases of oral cysticercosis.

This paper presents a review of 1018 oral biopsies in pediatric patients from the Oral Pathology Service, Minas Gerais Federal University, Brazil. The lesions were divided into ten main categories. The most common oral lesions in this study were follicular cyst in the maxillary anterior region, followed by inflammatory fibrous hyperplasia in the same region, and mucocele in the lower lip. Cysts of the jaws and oral soft tissues comprised 26.1 percent of total oral biopsies. The importance of these findings in oral diagnosis is discussed.

Objectives: Peripheral giant cell lesion (PGCL) and central giant cell lesion (CGCL) of the jaws have a distinct clinical behaviour. Whether such biological differences are supported by a distinct pattern of proliferation markers or cell cycle associated proteins expression is not known. Therefore the purpose of the present study was to compare the immunohistochemical expression of p53, MDM2, Ki-67, PCNA and the histochemical expression of argyrophilic nuclear organiser region (AgNOR) on PGCL and CGCL of the jaws., Materials and Methods: Paraffin wax blocks of 14 cases of PGCL and 12 cases of CGCL were retrieved. A biotin-streptavidin amplified system was used for identification of the antigens. The AgNOR number was also evaluated., Results: Ki-67 immunoreactivity was greater in the mononuclear cells of PGCL compared to CGCL. PCNA and AgNOR staining were similar in PGCL and CGCL. Prominent MDM2 immunoreactivity was observed in all tissues investigated. By contrast, there was no p53 immunoreactivity., Conclusions: Although CGCL present a more aggressive clinical behaviour, it has a decreased proliferative activity compared to PGCL. Finally, p53, MDM2, PCNA, Ki-67 immunohistochemical expression and AgNOR histochemical expression do not reflect their distinct biological behaviour.

Parathyroid adenomas are usually benign uniglandular tumors, and inactivation of several tumor suppressor genes, notably the MEN 1 gene, or activation of oncogenes have been implicated in the tumorigenesis. Genomic instability, indicative of the involvement of DNA mismatch repair genes, has not been previously described in parathyroid adenomas. A single large parathyroid adenoma was resected from an 8.5-yr-old Brazilian patient with no personal or family history of other endocrinopathies. Analysis of paired tumor-nontumor DNA using 23 microsatellite markers, located on chromosomes 1, 10, and 11 was carried out. Microsatellite instability was detected in nine markers (D1S191, D1S212, D1S413, D1S2848, RET, D11S901, D11S903, INSR, and INT2), whereas no allelic loss was detected with any of the analyzed markers. Immunohistochemical analysis of retinoblastoma protein expression revealed low levels of expression, but no histopathological signs of malignancy. We conclude that in this single, apparently sporadic parathyroid adenoma, DNA mismatch repair genes might be involved in parathyroid tumorigenesis.

Mdm2 protein is a cellular regulator of p53 protein activity. Minor salivary gland tumours were investigated for immunohistochemical expression of Mdm2 protein and for p53 gene status. Formalin-fixed sections were submitted to monoclonal antibody anti-Mdm2 through use of the streptavidin-biotin method. Nuclear immunoreactivity was scored 1 (0-25% nuclei positive), 2 (26-50%), 3 (51-75%) and 4 (> 75%). The scores found were: PLGA = 1-4; ACC = 3 and 4; ACA = 2 and 4; PA = 3. Genomic DNA of p53 gene exons 5-8 was examined by polymerase chain reaction and no alterations were detected. The strong immunohistochemical Mdm2 expression may represent an alternative mechanism to the development of salivary gland tumours.

Objective: The purpose of the present study was to compare the immunohistochemical expression of cell cycle-associated proteins in neuroblastic and melanocytic cell populations of melanotic neuroectodermal tumor of infancy., Study Design: Three cases of melanotic neuroectodermal tumor of infancy were selected. The immunohistochemical expression of MDM-2, p53, proliferating cell nuclear antigen, cyclin D1, and cyclin A was assessed through use of the streptavidin-biotin-peroxidase complex technique., Results: Positive immunostaining for MDM-2, proliferating cell nuclear antigen, cyclin D1, and cyclin A was occasionally observed in the large melanin-containing epithelioid cells., Conclusions: These data suggest that MDM-2 expression may be important for the development of melanotic neuroectodermal tumor of infancy and that the melanocytic cell population, not the neuroblastic one, is the proliferative component of the tumor.

Objective: To compare the argyrophilic nucleolar organizer region (AgNOR) count of cells collected from normal buccal mucosa of cigarette smokers with that obtained from nonsmokers., Study Design: Cytologic smears of normal buccal mucosa from 20 smokers and 20 nonsmokers were stained for AgNORs. The AgNOR count was established on 100 cells. The count values of groups were compared and analyzed using Student's unpaired t test., Results: The AgNORs were round and had a clustered distribution in both groups. The mean AgNOR count was statistically higher in cells of smokers than nonsmokers (P < .01)., Conclusion: Analysis of AgNORs suggests that cigarette smoking influences proliferative activity in cells of normal buccal mucosa.

Giant cell fibroma (GCF) is a non-neoplastic lesion of the oral mucosa. The origin of stellate and multinucleate cells of GCF is not well known. The purpose of the present article was to investigate the immunoreactivity of these cells for leukocyte common antigen, vimentin, tryptase, HLA-DR, alpha-smooth muscle actin, CD68, and S-100. The results showed positive staining only for vimentin. This suggests that the stellate and multinucleate cells of GCF have a fibroblast phenotype.

The role of L-,N-, P- and Q-type voltage-dependent calcium channels in K+-induced release of [3H]adenine nucleotides from rat brain cortical synaptosomes was investigated. Cd2+, a non-specific blocker of calcium channels, inhibited by 69% the release of the nucleotides induced by 33 mM K+. Nifedipine, omega-Conotoxin GVIA and omega-Agatoxin IVA had no effect whereas omega-Conotoxin MVIIC inhibited by 62% the K+ induced release of adenine nucleotides in rat brain cortical synaptosomes. It is concluded that Q-type calcium channels are directly involved in the release of adenine nucleotides in rat brain cortical synaptosomes.

Background: Myxoma is a rare bone tumor of the mandible and maxillary sinus whose etiology and underlying molecular mechanisms remain unknown. Mutations that inhibit the GTPase activity of the a subunit of the stimulating G protein (Gsa) have been demonstrated in the myocardium of patients with McCune-Albright syndrome. The histopathological similarities shared by cardiac and jaw myxomas coupled with the paucity of reported candidate genes involved in jaw tumor pathogenesis, prompted us to investigate for the presence of gsp mutations in 23 sporadic jaw myxomas., Materials and Methods: We used the polymerase chain reaction (PCR) to amplify the appropriate genomic fragments, followed by denaturing gradient gel electrophoresis (DGGE) analysis., Results: No gsp mutations could be demonstrated in any of tumors analyzed, while the technique has a proven capability to detect these specific mutations., Conclusions: We conclude that mutations of the Gs alpha gene rarely, if ever, are associated with sporadic jaw myxomas tumorigenesis.

Fine needle aspiration biopsy (FNAB) is an important technique in the diagnosis of oral and maxillofacial conditions. We describe here the cytological and immunocytological findings in four patients with central giant cell granuloma. All the aspirates showed mononuclear cells associated with many giant cells. We conclude that immunocytochemical examination of FNAB specimens helps to confirm the provisional clinical diagnosis of central giant cell granuloma.

Mushroom bodies are prominent neuropils found in annelids and in all arthropod groups except crustaceans. First explicitly identified in 1850, the mushroom bodies differ in size and complexity between taxa, as well as between different castes of a single species of social insect. These differences led some early biologists to suggest that the mushroom bodies endow an arthropod with intelligence or the ability to execute voluntary actions, as opposed to innate behaviors. Recent physiological studies and mutant analyses have led to divergent interpretations. One interpretation is that the mushroom bodies conditionally relay to higher protocerebral centers information about sensory stimuli and the context in which they occur. Another interpretation is that they play a central role in learning and memory. Anatomical studies suggest that arthropod mushroom bodies are predominately associated with olfactory pathways except in phylogenetically basal insects. The prominent olfactory input to the mushroom body calyces in more recent insect orders is an acquired character. An overview of the history of research on the mushroom bodies, as well as comparative and evolutionary considerations, provides a conceptual framework for discussing the roles of these neuropils.

Bilateral parotid aplasia and lacrimal puncta are a rare disorder. A case is presented in which the clinical diagnosis was confirmed by ultrasonography. The importance to dentists in early recognition of bilateral parotid aplasia and lacrimal puncta is emphasized.

Periapical lesions, as well as periodontal disease, seems to have cyclic patterns of evolution. Periods of burst may be intercalated with periods of quiescence. Because keratinocyte division must occur during cyst growth, it is presumed that epithelium status could indicate the biological activity of radicular cysts (RCs). Th1 and Th2 are important heterogeneous stages of lymphocyte differentiation. Delayed-type hypersensitivity immune reactions are mediated by Th1 lymphocytes, whereas Th2 populations mediate some types of humoral immune response. Th2 lymphocytes are characterized by high expression of CD30 glycoprotein. Th1 and Th2 lymphocytes have not been evaluated in periapical inflammatory lesions. The purpose of this study was to evaluate CD30+ cells in RCs with atrophic and hyperplastic epithelium. A biotin-streptavidin amplified system was used for identification of CD30 receptor. Results demonstrate increased proportions of Th2 cells in cysts with hyperplastic epithelium. Our results suggest that Th2 cells could be associated with RC growth.

Th2 type lymphocytes are characterized by high expression of CD30 glycoprotein. Increased serum levels of CD30 and Th2 IL-4 producing T-cells are found during AIDS progression. Since HIV-positive patients are more susceptible to periodontal disease, quantitative analysis of positive cells for the CD30 receptor in chronic gingivitis of both HIV-infected and non-infected patients (NSG) would help to clarify the immunoregulation of HIV-associated periodontal diseases. The purpose of this study was to evaluate CD30+ lymphocytes in gingival biopsies from sites exhibiting chronic gingivitis on HIV-positive patients (CG-HIV) and NSG. A biotin-streptavidin amplified system was used for identification of the CD30 receptor. The results demonstrated increased proportions of Th2 cells in CG-HIV as compared to NSG. Additional studies are necessary to understand the importance of these cells to the biological activity or inactivity of the disease.

Purpose: To present a case of brainstem anaesthesia as a complication of peribulbar anaesthesia., Clinical Features: A 75-yr-old woman received peribulbar anaesthesia for cataract surgery. A few seconds after the block performed, she had a respiratory arrest, became unconscious, and developed hypertension and tachycardia followed by hypotension and bradycardia. Ventilatory and haemodynamic support were performed before the patient regained adequate spontaneous breathing, and normal heart rate and blood pressure., Conclusion: Peribulbar anaesthesia generally carries a low risk of serious complications. However, respiratory arrest and brainstem anaesthesia may occur as complications of peribulbar blocks.

The glycoprotein CD36 functions as a thrombospondin receptor and is expressed on a variety of cell types, including platelets, monocyte/macrophages, and endothelial cells. In human skin, the presence of CD36 on keratinocytes was initially found in lesional areas of T-cell mediated inflammatory dermatoses. Controversy still exists on the interpretation of this expression as an inflammatory or differentiation-associated marker. So far, only limited data are available on CD36 expression in oral epithelia. The present immunohistochemical study was therefore performed to determine the presence of CD36 on keratinocytes of healthy and disease-affected epithelia of the oral cavity in 80 biopsy specimens. As results, we found an inflammation-independent strong expression of CD36 in oral epithelia with ortho- and parakeratinization, such as the oral side of the gingiva, the hard palate, and the back of the tongue. Non-keratinized epithelia such as the gingival pocket epithelium, the soft palate, the lip, the buccal mucosa, and the side of the tongue were CD36 negative. We therefore suggest that CD36 expression in keratinocytes from oral epithelia is an epithelial differentiation marker.

1. The effect of reducing reagents on omega-conotoxin GVIA (omega-CgTX) inhibition of the release of [3H]-acetylcholine ([3H]-ACh) induced by tityustoxin, K+ 50 mM and electrical stimulation was investigated in rat brain cortical slices. 2. In cortical slices the inhibition of tityustoxin or electrically-stimulated [3H]-ACh release by omega-CgTX was dramatically increased by reducing reagents ascorbate or beta-mercaptoethanol. Dehydroascorbic acid did not substitute for ascorbate. 3. Depolarization induced by K+ 50 mM caused [3H]-ACh release from cortical slices which was not inhibited by omega-CgTX, even in the presence of ascorbate. 4. In the guinea-pig myenteric plexus, omega-CgTX inhibition of the tityustoxin induced release of [3H]-ACh was independent of ascorbate. 5. It is suggested that N-type-like calcium channels in guinea-pigs myenteric plexus may have pharmacological/biochemical diversity from similar channels of rat cerebral cortex.

The dentinogenic ghost-cell tumor is a rare solid variant of the calcifying odontogenic cyst. Few peripheral cases of this tumor with clinical and radiographic documentation have been reported. A case of peripheral dentinogenic ghost-cell tumor is presented and the literature is reviewed.

Ouabain, an Na+K+ATPase inhibitor, increases the release of acetylcholine (ACh) from various preparations in a Ca2+ -independent way. However, in other preparations the release of ACh evoked by ouabain is dependent on the presence of extracellular calcium. In the present study, we have labeled the ACh of myenteric plexus longitudinal muscles of guinea pig ileum and compared the effect of calcium channel blockers on ouabain-evoked release of [3H]ACh. Release of [3H]ACh evoked by ouabain is dose dependent and decreased markedly in the absence of calcium or in the presence of cadmium, a nonspecific calcium channel blocker. N-type calcium channel blockage by the omega-conotoxins GVIA (selective N-type calcium channel blocker) and MVIC (a nonselective calcium channel blocker) inhibited by 45 and 55%, respectively, the release of [3H]ACh. L-type calcium channel suppression by low concentrations of verapamil, nifedipine, and diltiazem had no effect on the release of [3H]ACh. The release of transmitter was also not affected significantly by nickel, a T-type calcium channel blocker. In addition, omega-agatoxin-IVA, at concentrations that block P- and Q-type calcium channels, did not affect significantly the release of [3H]ACh. Thus, extracellular Ca2+ is essential for the release of ACh induced by ouabain from guinea pig ileum myenteric plexus. In this preparation, the N-type calcium channel plays a dominant role in transmitter release evoked by inhibition of Na+K+-ATPase, but other routes of calcium entry in addition to these channels can also support the release of neurotransmitter induced by ouabain.

The melanotic neuroectodermal tumor of infancy (MNTI) is an uncommon benign neoplasm frequently detected in young infants, which has a predilection for the head and neck region, particularly maxilla. The purpose of this article is to present a documented case of MNTI and discuss clinical, radiological and histopathological features of the disease. The biological behavior of the tumor is emphasized.

Clear-cell ameloblastoma (clear-cell odontogenic carcinoma) is an uncommon odontogenic epithelial neoplasm. We report a case of a well-circumscribed 2 cm radiolucent lesion of the anterior mandible in a 30-year-old woman; this tumor was curetted. The first recurrence (at 5-year follow-up) was treated by aggressive curettage, and in the second recurrence a block resection was performed. However, 2 years after the resection was performed, the tumor recurred for a third time as an extraosseous gingival tumor, and 6 months later a recurrence was noted involving only alveolar mucosa.

The venom of the Brazilian spider Phoneutria nigriventer possesses several neurotoxic polypeptidic fractions. Previous work has established that one of the toxic components, PhTx3, inhibited Ca(2+)-dependent glutamate release and the increase in cytosolic free Ca2+ in response to membrane depolarization. In the present work, we investigated the effect of PhTx3 on the release of acetylcholine (ACh) from brain and peripheral neurons. PhTx3 decreased the release of [3H]-ACh induced by tityustoxin and KCl in brain cortical slices and myenteric plexus. The inhibitory effect of myenteric plexus had the same magnitude as that obtained in the absence of extracellular Ca2+. However, in brain PhTx3 was less efficient at decreasing the evoked release of ACh. These experiments suggest that the target of PhTx3 is coupled to the process of release of ACh in brain and autonomic nervous system.

In this paper, the effect of calcium channel blockers on acetylcholine release induced by tityustoxin and ouabain in rat brain cortical slices is described. Cadmium, a non-specific blocker of calcium channels, inhibited the release of ACh induced by tityustoxin. L-type calcium channel blockers (verapamil, nifedipine and diltiazen) had no effect on the release of ACh induced by tityustoxin. The release of ACh was also unaffected by nickel, a T-type calcium channel blocker, and the conotoxins GVIA and MVIIC, blockers of N and Q-type calcium channels. Agatoxin IVA, a specific blocker of the P-type calcium channel, inhibited the release of ACh induced by tityustoxin by 50%. The spontaneous release of ACh as well as ouabain-induced release of ACh was unaffected by any of the calcium channel blockers studied. It is concluded that ACh release induced by tityustoxin is mediated by Ca2+ influx via P-type calcium channels.

Objective: To study the nature of multinucleated and mononuclear cells from peripheral giant cell granuloma (PGCG)., Materials and Methods: Formalin-fixed, paraffin-embedded sections of 40 cases of PGCG were immunohistochemically stained for vimentin, alpha I-antichymotrypsin, CD68, S-100 protein, lysozyme, leucocyte common antigen (LCA), factor VIII-related antigen and muscle cell actin. Six cases of PGCG were also studied by transmission electron microscopy., Results: Vimentin, alpha I-antichymotrypsin and CD68 were expressed in both the mononuclear and multinucleated giant cells. Dendritic mononuclear cells, positive for S-100 protein, were noted in 67.5% of the lesions, whereas lysozyme and leucocyte common antigen were detected in occasional mononuclear cells. Ultrastructural examination showed mononuclear cells with signs of phagocytosis and sometimes interdigitations with similar cells. Others presented non-specific characteristics and the third type exhibited cytoplasmic processes and occasional Birbeck granules. Some multinucleated giant cells showed oval nuclei, abundant mitochondria and granular endoplasmic reticulum whereas others presented with irregular nuclei and a great number of cytoplasmic vacuoles., Conclusions: Immunohistochemical and ultrastructural results suggest that PGCGs of the jaws are composed mainly of cells of the mononuclear phagocyte system and that Langerhans cells are present in two thirds of the lesions.

Exposure of myenteric plexus longitudinal muscles to 2 mM LaCl3 increased the rate of spontaneous [3H]-ACh release. In brain cortical slices La3+ did not affect the spontaneous release of ACh. The release of ACh induced by tityustoxin, ouabain or K+ 50 mM in brain cortex and myenteric longitudinal muscles slices was inhibited by La3+ treatment. It is suggested that tityustoxin, ouabain and K+ release ACh from the same pool that is inhibited by La3+ pretreatment.

The work proposes to report a case of Squamous Odontogenic Tumor describing all clinical, radiographic and histopathological findings. A review on literature discussing the tumor etiology is presented.

We report six cases of acute neutrophilic dermatosis (Sweet's syndrome). Clinical and laboratory data as well as the results of further examination of the patients are presented. Unusually associated disorders, such as Crohn's disease together with an erythema nodosum or adenocarcinoma of the colon, were diagnosed in these patients.