Proliferation of fibroblasts cultured from normal gingiva and hereditary gingival fibromatosis is dependent on fatty acid synthase activity.

BACKGROUND: Fatty acid synthase (FAS) is the enzyme that synthesizes palmitate from malonyl-CoA and acetyl-CoA. Recent studies have shown that FAS is overexpressed in human cancers and that its activity is necessary for cell proliferation. Hereditary gingival fibromatosis (HGF) is a genetic disease manifested as a progressive enlargement of the gingiva. The pathogenesis of this condition is not understood; however, a proliferative advantage of HGF fibroblasts in comparison with cells from normal gingiva (NG) has been described. The aim of this study was to investigate the role of FAS in NG and HGF fibroblast proliferation. METHODS: NG and HGF fibroblasts had their proliferative potential assessed by automated cell counting and immunocytochemistry against Ki-67 or proliferating cell nuclear antigen (PCNA). The production of FAS, androgen receptor (AR), and ErbB2 was analyzed by Western blot and the pattern of FAS expression studied by immunocytochemistry. FAS activity was blocked by the specific inhibitor cerulenin. RESULTS: Higher proliferation rates were found in fibroblasts isolated from HGF than from NG. HGF fibroblasts with greater proliferative potential produced more FAS and AR than the cell lines with lower growth rates, and all studied cell lines produced similar amounts of the ErbB2 protein. In addition, the FAS inhibitor cerulenin was able to significantly reduce the proliferation of both NG and HGF cells. CONCLUSIONS: These results show that FAS is expressed by gingival fibroblasts and that highly proliferative HGF cells produced more FAS and AR than the other fibroblast cell lines. Moreover, FAS inhibition significantly reduced both NG and HGF fibroblast growth, suggesting a role for the androgen-driven fatty acid biosynthesis in their proliferation.

Ultrastructural aspects of connective tissue in hereditary gingival fibromatosis.

OBJECTIVE: The purpose of this study was to analyze the ultrastructure of gingival connective tissue from patients in one family affected by hereditary gingival fibromatosis (HGF). STUDY DESIGN: Electron microscopic examination was performed with gingival tissue from 10 patients from a Brazilian family with 132 members. Fifty of 96 persons at risk for this disorder were affected, which is consistent with an autosomal dominant pattern of inheritance. RESULTS: The extracellular matrix showed flocculent material and collagen fibrils with structural abnormalities and variation in diameter. Increased numbers of oxytalan fibers were identified; however, elastic fibers were rare in the analyzed areas. CONCLUSIONS: The structural alterations found in HGF appear similar to those described in certain other heritable collagen disorders, suggesting that HGF should be included in the group of hereditary diseases in which connective tissue alterations have a distinct pattern, in contrast to reactive fibrotic gingival enlargements with no genetic component.

Evidence of genetic heterogeneity for hereditary gingival fibromatosis.

Hereditary Gingival Fibromatosis (HGF) is the most common genetic form of gingival fibromatosis. The condition is most frequently reported to be transmitted as an autosomal-dominant trait, but autosomal-recessive inheritance has also been reported. The clinical presentation of HGF is variable, both in the distribution (number of teeth involved) and in the degree (severity) of expression. It is unknown if the variable clinical expression of HGF in different families is due to variable expression of a common gene mutation, allelic mutations, or non-allelic mutations. The apparently different modes of Mendelian inheritance of HGF suggest genetic heterogeneity. A gene locus for HGF has been localized to a 37-cM genetic interval on chromosome 2p21-p22 (D2S1352, Zmax = 5.10, theta = 0.00) flanked by D2S1788 and D2S441. To evaluate the generality of this linkage, we tested linkage with 9 markers from this candidate region in another large family, segregating for an autosomal-dominant form of generalized HGF, and found no support for linkage with any of these markers. Furthermore, statistical tests of this apparent heterogeneity were highly significant. Analysis of these data provides direct evidence that at least two genetically distinct loci are responsible for autosomal-dominant hereditary gingival fibromatosis.

Hereditary gingival fibromatosis: report of three cases.

Three cases of generalized and severe HGF in young patients of the same family without other features are reported. The purpose of this article is to present documented cases and discuss the identification, treatment, and control of the disease. The histopathological characteristics of HGF are emphasized.

Differential proliferation of fibroblasts cultured from hereditary gingival fibromatosis and normal gingiva.

Hereditary gingival fibromatosis (HGF) is an oral condition characterized by the enlargement of the gingiva of both the maxilla and mandible. To study the cell proliferation index of fibroblasts from HGF and normal gingiva (NG), cell cultures from 4 members of the same family with HGF and from 4 healthy patients were established. Our results obtained from 6 different cell proliferation assays clearly showed that the cell proliferation rate was significantly higher in fibroblasts from HGF than from normal gingiva. HGF and control fibroblasts in subconfluent culture densities were typically spindle, but in saturation density HGF cells were shorter than control cells. These data suggest that the higher proliferative index of HGF fibroblasts possibly has a role in the pathogenesis of gingival outgrowth in HGF patients.

Titanium implants in rabbit femur: a histologic evaluation.

The success achieved by Scandinavian researchers in the development of long-term implants has stimulated many dentists to apply them worldwide. However, most of the implants did not have sufficient scientific support. The purpose of this study was to evaluate host tissue response to the insertion of an endosseous dental implant. Twenty adult New Zealand rabbits were used. Histological evaluation was prepared from the femurs. Results showed a hemorrhagic aspect and inflammatory infiltration which was subsequently substituted by granulation tissue, and later, formation of bone tissue. In the cortical bone, the presence of a necrotic area was observed which was later remodelled, and also an intense proliferation of endosteum and periosteum in the regions next to the implant, resulting in a thickening of the cortical bone surface close to the implant. Therefore, it was observed that titanium implants (Carbontec-Special Materials Ltda.) did not interfere with the bone healing process.

Hereditary gingival fibromatosis. Report of an extensive four-generation pedigree.

A Brazilian family with hereditary gingival fibromatosis is described with multiple affected subjects in four generations. A total of 50 (48%), of 105 at-risk offspring in a family of 132 members were affected, consistent with an autosomal dominant mode of inheritance. This family appears to represent the largest pedigree with this condition reported in the literature.

Oral paracoccidioidomycosis. A study of 36 South American patients.

Paracoccidioidomycosis (South American blastomycosis) is an uncommon, progressive systemic mycosis, virtually only seen in persons who have visited Latin America. Reports of oral lesions are extremely rare in the English-language literature. Thirty-six adults with oral lesions as the first sign of paracoccidioidomycosis are described; this appears to be the largest series in the dental literature. All had chronic proliferative mulberry-like ulcerated oral lesions; the diagnosis was confirmed histologically. The gingiva or alveolar process was the typical site, but lesions were also seen particularly on the palate and lip. Most of the patients proved to have detectable pulmonary involvement. Patients with lesions in the oropharynx, tongue, or floor of mouth all had confirmed pulmonary lesions.

Oral myiasis caused by sarcophagidae in an extraction wound.

Oral myiasis (infestation by the larvae of Diptera flies) has only rarely been reported in the English-language literature. This article records a case of wound myiasis caused by flies of the family Sarcophagidae that affected a tooth-extraction site, and was a painful complication of the extraction.

Familial gingival hyperplasia: a case of pseudo-Laband syndrome.

Three siblings with familial gingival hyperplasia and abnormal feet are reported. Despite the resemblance to the Laband syndrome, where there are anomalies of the terminal phalanges, the abnormalities of the feet in these children were caused by the persistent wearing of "flip-flop" sandals. Care is required in the conduct of history and examination.

Oral manifestations of paracoccidioidomycosis (South American blastomycosis).

Paracoccidioidomycosis (South American blastomycosis) is an uncommon, progressive systemic mycosis, potentially fatal if untreated. It is virtually restricted to persons spending time in Latin America. Reports of oral lesions are extremely rare in the English-language literature. Three adults with oral lesions as the first sign of paracoccidioidomycosis are described; this appears to be the largest series in the dental literature. The oral lesions had a characteristic appearance with a granular purpuric surface. The upper gingiva was a typical site, but lesions were also seen in the palate, tongue, and buccal mucosa. Two of the patients proved to have detectable pulmonary involvement. Long-term systemic ketoconazole therapy produced resolution of oral lesions in all cases.

Oral mucosal health and disease in institutionalized elderly in Brazil.

During the last decade, many studies in Europe and North America have evaluated oral conditions and dental needs in the elderly. Similar information does not exist in Brazil. The aim of this study was to determine the prevalence of oral health and disease in elderly persons living in an institution in the city of Piracicaba, State of São Paulo, Brazil. Of 350 elderly persons, 134 males and 136 females were interviewed and clinically examined. Less than one half had healthy mouths. 58.9% of the examined individuals showed one or more lesions in the oral mucosa, the most frequent being denture-induced stomatitis (20.0%). Fibrous hyperplasias (11.8%) and angular cheilitis (9.3%) were fairly common. Gender, use and degree of hygiene of the denture were factors statistically significantly contributing to prevalence of denture stomatitis. Precancerous lesions such as leukoplakia (3.0%), actinic cheilitis (2.6%) were uncommon but three cases of squamous carcinoma (1.1%) were revealed. This study emphasizes the need for regular oral examinations of the elderly by personnel trained in oral diagnosis.

Orofacial manifestations from accidental exposure to caesium 137 in Goiania, Brazil.

The accidental close exposure of over 200 adults and children to a caesium-137 (137Cs) source in Goiania, Brazil in 1987 produced significant short-term morbidity in about 50 patients, and four deaths within a few weeks. Some 57% of those maximally exposed to radiation, developed orofacial lesions, notably purpura, spontaneous bleeding, ulcers and/or acute candidiasis. These lesions were probably mainly the consequences of depression of bone marrow elements by the radionuclide. Though the oral lesions that may follow iatrogenic exposure to ionizing radiation are well recognized this appears to be the first report on the oral sequelae of a serious radiation accident.

[Biomechanics of orthodontic movement--initial response of periodontal tissue]. / Biomecánica da movimentação ortodôntica--resposta inicial dos tecidos periodontais.

There occurs a biological response of the tissues of dental support, in answer to the external physiological forces and those realized during clinical treatments with orthodontical purposes. These forces differ from the first ones because they are continuous and time dependent. A great dental mobility is related to the degree of tissue organization of the periodontium system and the orthodontical movement must utilize this exceptional capacity of renewal and adaptation of the periodontium structures adequately. Therefore, through histological means a search was made to evaluate the succession of alterations of the periodontium system after the application of an orthodontical force on the molars of young rats and to interpret the standards of horizontal mobility and their consequences on the periodontium structures, biologically. An orthodontic force was applied on young rats utilizing steel wire placed in a ring form on a contact point between the first and second lower molars. The animals were sacrificed after 30 minutes, 1, 2, 6, 12, 24, 48, 72, 96 and 168 hours after the placement of the metal ring. After technical preparation, the microscopic slides were examined and the results were compared. In all the sections there was evidence of an intense metabolic activity. A gradual evolution of modification on the phenomenons had occurred.

Presenca de eosinofilos na doenca periodontal de ratos. / Presence of oesinophils in periodontal disease of rats

Eosinofilos estavam presentes na inflamacao gengival provocada experimentalmente em ratos, colocando-se ligadura com fio de algodao na regiao cervical dos 1os. molares inferiores. O numero de eosinofilos aumentou progressivamente ate 30 dias apos a colocacao do irritante gengival, nao havendo posteriormente modificacoes quantitativas. Inicialmente os eosinofilos estavam localizados nas areas inflamadas subjacentes ao epitelio e depois de 30 dias situavam-se no corion mais profundo, entre as fibras de colageno. Mastocitos raramente foram observados no tecido periodontal proximo as areas inflamadas, indicando que estas celulas nao atuaram diretamente na migracao dos eosinofilos. Alem da participacao dos eosinofilos em mecanismos imunologicos sugere-se que possam estar envolvidos no metabolismo de fibras colagenas

Immune response to oral ingestion of Streptococcus mutans in gnotobiotic rats: histological findings.

A resposta imunologica a ingestao oral de Streptococcus mutans foi estudada atraves de imunofluorescencia em diferentes tecidos de ratos gnotobioticos. As seccoes foram tratadas com antisoro marcado com fluoresceina para as cadeias alfa, mu e gama. O numero de celulas fluorescentes foi significativamente maior nos tecidos dos animais tratados quando comparados com o grupo controle, gnotobiotico nao tratado. A contagem de leucocitos no sangue periferico mostrou variacoes en relacao ao grupo controle