201
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Bonan PRF, Lopes MA, Alves FDA, Almeida OPD. Aspectos clínicos, biológicos, histopatológicos e tratamentos propostos para a mucosite oral induzida por radioterapia: revisão da literatura. REVISTA BRASILEIRA DE CANCEROLOGIA 2005. [DOI: 10.32635/2176-9745.rbc.2005v51n3.1951] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
A mucosite oral é um dos principais efeitos colaterais agudos induzidos pelo tratamento radioterápico em cabeça e pescoço, surgindo a partir da segunda semana de tratamento e é caracterizada por ardência bucal até sintomatologia dolorosa intensa exigindo em algumas situações a interrupção do tratamento radioterápico. O objetivo desse trabalho foi rever os principais trabalhos publicados que discutem as características clínicas, histopatológicas e tratamentos propostos para a mucosite oral induzida por radioterapia. Poucos estudos descreveram os aspectos histopatológicos da mucosite oral e apenas recentemente os mecanismos biológicos começaram a ser desvendados. Embora diversas modalidades terapêuticas sejam indicadas para a prevenção e tratamento da mucosite oral, não existe consenso sobre o tratamento mais indicado. A melhor compreensão dos mecanismos biológicos e da histopatologia provavelmente contribuirá para a indicação de terapias eficazes na prevenção e manejo da mucosite oral.
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202
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Rodrigues JM, Luís AL, Lobato JV, Pinto MV, Faustino A, Hussain NS, Lopes MA, Veloso AP, Freitas M, Geuna S, Santos JD, Maurício AC. Intracellular Ca2+ concentration in the N1E-115 neuronal cell line and its use for peripheric nerve regeneration. ACTA MEDICA PORT 2005; 18:323-8. [PMID: 16611536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Entubulation repair of peripheral nerve injuries has a lengthy history. Several experimental and clinical studies have explored the effectiveness of many biodegradable and non-degradable tubes with or without addition of molecules and cells. The main objective of the present study was to develop an economical and also an easy way for culturing a neural cell line which is capable of growing, differentiating and producing locally nerve growth factors, that are otherwise extremely expensive, inside 90 PLA/10 PLG nerve guides. For this purpose the authors have chosen the N1E-115 cell line, a clone of cells derived from mouse neuroblastoma C-1300 with the perspective of using this differentiated cellular system to cover the inside of 90 PLA/10 PLG nerve guides placed to bridge a nerve gap of 10 mm in the rat sciatic nerve experimental model. The N1E-115 cells proliferate in normal culture medium but undergo neuronal differentiation in response to DMSO. Upon induction of differentiation, proliferation of N1E-115 cells ceases, extensive neurite outgrowth is observed and the membranes become highly excitable. While it is known that Ca2+ serves as an important intracellular signal for cellular various processes, such as growth and differentiation, be toxic to cells and be involved in the triggering of events leading to excitotoxic cell death in neurons. The [Ca2+]i in non-differentiated N1E-115 cells and after distinct periods of differentiation, have been determined by the epifluorescence technique using the Fura-2-AM probe. The results of this quantitative assessment, revealed that N1E-115 cells which undergo neuronal differentiation for 48 hours in the presence of 1.5% DMSO are best qualified to be used to cover the interior of the nerve guides since the [Ca2+]i was not found to be elevated indicating thus that the onset the cell death processes was not occurred.
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203
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Takahama AJ, Tatsch F, Tannus G, Lopes MA. Hepatitis C: incidence and knowledge among Brazilian dentists. COMMUNITY DENTAL HEALTH 2005; 22:184-7. [PMID: 16161884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
OBJECTIVES To evaluate the incidence of Hepatitis C among dentists from the city of Piracicaba-SP--Brazil, and also to analyze the knowledge of this disease among these health care workers. DESIGN Two hundred and sixty-seven dentists completed a questionnaire and supplied a sample of blood for serologic testing for hepatitis C virus (HCV). RESULTS Only one participant was positive for HCV, representing 0.4% of total. There was a lack of knowledge of this disease among dentists. CONCLUSIONS There is an occupational risk of infection for HCV in dentistry and there is a need to make professionals aware of it.
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204
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Ito FA, Ito K, Vargas PA, de Almeida OP, Lopes MA. Salivary gland tumors in a Brazilian population: a retrospective study of 496 cases. Int J Oral Maxillofac Surg 2005; 34:533-6. [PMID: 16053874 DOI: 10.1016/j.ijom.2005.02.005] [Citation(s) in RCA: 143] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2003] [Revised: 11/04/2004] [Accepted: 02/04/2005] [Indexed: 11/19/2022]
Abstract
Salivary gland tumors are uncommon and the microscopical features can be complex. Epidemiological data of these tumors in the various parts of the world can be helpful for a better understanding of its biology and clinical characteristics. In this study, 496 epithelial and mesenchymal tumors of major and minor salivary glands diagnosed at Londrina Cancer Institute during the period from 1972 to 2001 were reviewed. Out of all cases, 335 (67.5%) were classified as benign and 161 (32.5%) as malignant. The majority of the cases occurred in the parotid gland (67.7%), followed by the minor salivary glands (22.8%) and submandibular gland (9.5%). Among the minor salivary gland tumors, the palate was the most frequent location (67%). The tumors affected more commonly adult patients with peak incidence between 40 and 50 years of age and with a slightly predominance in females. Pleomorphic adenoma was the most frequent tumor representing 54.2% of all cases, followed by mucoepidermoid carcinoma (13.5%), Warthin's tumor (8.5%) and adenoid cystic carcinoma (7.9%).
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205
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Pereira CM, Jorge J, Di Hipólito O, Kowalski LP, Lopes MA. Primary intraosseous fibrosarcoma of jaw. Int J Oral Maxillofac Surg 2005; 34:579-81. [PMID: 16053882 DOI: 10.1016/j.ijom.2004.10.015] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2003] [Revised: 05/10/2004] [Accepted: 10/22/2004] [Indexed: 11/30/2022]
Abstract
This paper reports one case of primary fibrosarcoma affecting the mandible in a 41-year-old woman. Microscopically, the tumor was cellularized with an intense mitotic activity, and areas of necrosis and hemorrhage, and the cells showed immunoreactivity only for vimentin, establishing the diagnosis of primary intraosseous fibrosarcoma. The patient underwent tumor surgical resection, supraomohyoid neck dissection and mandible reconstruction with fibula flap and titanium bar. She also received post-surgical radiotherapy and is in follow up for 36 months without signs of recurrence or metastases.
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206
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Pereira CM, Coletta RD, Jorge J, Lopes MA. Peutz-Jeghers syndrome in a 14-year-old boy: case report and review of the literature. Int J Paediatr Dent 2005; 15:224-8. [PMID: 15854121 DOI: 10.1111/j.1365-263x.2005.00627.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Peutz-Jeghers syndrome (PSJ) is a relatively rare but well-recognized condition, with a prevalence of approximately one in 120,000 births in the USA. It is generally inherited as an autosomal dominant trait, although 35% of cases are new mutations. This disorder is characterized by melanocytic macules on the hands, feet, peri-oral skin and oral mucosa, and multiple gastrointestinal hamartomatous polyps. People with PSJ have an increased risk for developing a variety of malignant tumours. The aim of the present study was to report one case of PSJ in a 14-year-old boy with mucocutaneous pigmentation associated with duodenal hamartomatous polyps.
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207
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Abstract
Sturge-Weber syndrome is a congenital disorder characterized by vascular facial birthmarks and neurological abnormalities. Oral cavity involvement may occur, and the extent of the vascular abnormality may vary considerably. The present authors report the case of a 6-year-old girl with Sturge-Weber syndrome, focusing on the clinical and radiographic features. Her dental management involved a multidisciplinary team and included orthodontic treatment using removable appliances.
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208
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Oliveira JM, Miyazaki T, Lopes MA, Ohtsuki C, Santos JD. Bonelike/PLGA hybrid materials for bone regeneration: preparation route and physicochemical characterisation. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2005; 16:253-259. [PMID: 15744617 DOI: 10.1007/s10856-005-6687-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2003] [Accepted: 06/23/2004] [Indexed: 05/24/2023]
Abstract
Bonelike/PLGA hybrid materials have been developed using gamma-MPS as silane-coupling agent between the inorganic and organic phases for controlled drug delivery applications. Silanization showed to be more effective when cyclohexane was used as a non-polar solvent (nP method) due to a chemical interaction between Bonelike, and the silane film, while by using a 95/5 (V/V) methanol/water as a polar solvent (P method), a much thinner film was achieved. Functional groups of PLGA, such as the carbonyl group (C=O), were identified using Raman and FTIR-ATR analysis and therefore these groups may be used to link therapeutic molecules. These novel hybrid materials prepared by combining silanization and post-hybridisation processes are expected to find use in medical applications of bone regeneration and as drug delivery carrier for therapeutic molecules.
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209
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Hess TM, Kronfeld DS, Crandell KE, Waldron JN, Treiber K, Staniar WB, Lopes MA, Harris PA. Fat adaptation affects insulin sensitivity and elimination of horses during an 80 km endurance ride. PFERDEHEILKUNDE 2005. [DOI: 10.21836/pem20050740] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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210
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Rodrigues JM, Luís AL, Lobato JV, Pinto MV, Lopes MA, Freitas M, Geuna S, Santos JD, Maurício AC. Determination of the intracellular Ca2+ concentration in the N1E-115 neuronal cell line in perspective of its use for peripheric nerve regeneration. Biomed Mater Eng 2005; 15:455-65. [PMID: 16308461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Entubulation repair of peripheral nerve injuries has a lengthy history. Several experimental and clinical studies have explored the effectiveness of many biodegradable and non-degradable tubes with or without addition of molecules and cells. The main objective of the present study was to develop an economical and also an easy way for culturing a neural cell line which was capable of growing, differentiating and producing locally nerve growth factors that are otherwise extremely expensive, inside 90 PLA/10 PLG nerve guides. For this purpose the authors have chosen the N1E-115 cell line, a clone of cells derived from mouse neuroblastoma C-1300 with the perspective of using this differentiated cellular system to cover the inside of 90 PLA/10 PLG nerve guides placed to bridge a gap in the rat sciatic nerve experimental model. The N1E-115 cells proliferate in normal culture medium but undergo neuronal differentiation in response to DMSO. Upon induction of differentiation, proliferation of N1E-115 cells ceases, extensive neurite outgrowth is observed and the membranes become highly excitable. While it is known that Ca2+ serves as an important intracellular signal for various cellular processes, such as growth and differentiation. It is also known that can be toxic to cells and is involved in the triggering of events leading to excitotoxic cell death in neurons. The [Ca2+]i in non-differentiated N1E-115 cells and after distinct periods of differentiation, have been determined by the epifluorescence technique using the Fura-2-AM probe. The results of this quantitative assessment revealed that N1E-115 cells which undergo neuronal differentiation for 48 hours in the presence of 1.5% DMSO are best qualified to be used to cover the interior of the nerve guides since the [Ca2+]i was not found to be elevated indicating thus that the onset the cell death processes was not occurred.
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211
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Abstract
Tuberculosis is one of the major causes of ill health and death worldwide. Nevertheless, tuberculous lesions of the oral cavity are rare and can be a diagnostic challenge, particularly in young immunocompetent patients. Most of the cases are secondary to pulmonary disease and the primary form is uncommon. In this paper, we present a case of primary oral tuberculosis, affecting the floor of mouth in a 13-year-old Brazilian male patient.
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212
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Dias AG, Lopes MA, Trigo Cabral AT, Santos JD, Fernandes MH. In vitro studies of calcium phosphate glass ceramics with different solubility with the use of human bone marrow cells. J Biomed Mater Res A 2005; 74:347-55. [PMID: 15988737 DOI: 10.1002/jbm.a.30357] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Two glass ceramics in the CaO--P2O5--MgO system with the incorporation of K2O or TiO2 oxides were prepared with the goal of using them as potential bone graft substitutes. The incorporation of TiO2 and K2O led to the preparation of specific crystalline phases in the structure of the glass ceramics, which show different degrees of biodegradation. In fact, the 45CaO--45P2O5--5MgO--5K2O has been previously demonstrated to be much more soluble in aqueous solutions than the 45CaO--37P2O5--5MgO--13TiO2 glass ceramic. The in vitro biological activity of the two calcium phosphate glass ceramics was studied with the use of human bone marrow osteoblast cell cultures maintained for 28 days, and seeded materials were assessed for cell proliferation and function. The Ti-containing glass ceramic showed a stable surface throughout the culture time, on macroscopic and SEM observation. Osteoblast cells proliferated gradually, especially during the third week, with a high alkaline phosphatase activity and formation of a mineralized matrix. On SEM observation, attached cells appeared with a spread-polygonal morphology typical of the osteoblast cells, with extensive cell-to-cell contact. Cell behavior on the seeded material was similar to that found on cultures performed on tissue-culture-grade polystyrene; except for the presence of lower cell numbers during the first 2 weeks. By contrast, the K-containing glass ceramic showed a highly instable surface with dissolution/precipitation processes occurring throughout the culture time. Few cells adhered to the material surface, and subsequent proliferation was also hindered, especially from the first week onwards. Cell numbers were significantly lower than those observed in the Ti-containing glass ceramic during most of the incubation time. Results suggest that the different in vitro biological behavior of these two glass ceramics is mainly due to the significant differences in the surface degradation rate, which is directly correlated to the chemical composition of the mother glass.
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213
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Alves FA, Pires FR, De Almeida OP, Lopes MA, Kowalski LP. PCNA, Ki-67 and p53 expressions in submandibular salivary gland tumours. Int J Oral Maxillofac Surg 2004; 33:593-7. [PMID: 15308260 DOI: 10.1016/j.ijom.2004.01.010] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/08/2004] [Indexed: 10/26/2022]
Abstract
Salivary gland tumours are uncommon with a broad heterogeneity. The most common benign tumour is the pleomorphic adenoma, whereas mucoepidermoid carcinoma and adenoid cystic carcinoma predominate among the malignancies. Most salivary gland tumours occur in the parotid, and consequently clinical and biological data are normally derived from this site. This work describes the expressions of PCNA, Ki-67 and p53 in 15 pleomorphic adenomas, 15 mucoepidermoid carcinomas and 15 adenoid cystic carcinomas of the submandibular gland. Our results showed that all pleomorphic adenomas were negative for p53 and Ki-67 with 66.6% being positive for PCNA. Conversely, p53 was positive in 53% of the mucoepidermoid carcinomas and in 20% of the adenoid cystic carcinomas. Ki-67 was expressed in 47.7% of the mucoepidermoid carcinomas and 40% of the adenoid cystic carcinomas. All malignant tumours were positive for PCNA. These results indicate that the proliferative rate analysed with PCNA and Ki-67 and the expression of p53 in pleomorphic adenoma and adenoid cystic carcinoma of the submandibular gland were similar to those described in the parotid and minor salivary glands. However, mucoepidermoid carcinomas showed higher expression of these markers than those of other salivary glands. This work is the first describing the expression of these immunohistochemical markers exclusively in submandibular salivary gland tumours.
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214
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Cerqueira EMM, Gomes-Filho IS, Trindade S, Lopes MA, Passos JS, Machado-Santelli GM. Genetic damage in exfoliated cells from oral mucosa of individuals exposed to X-rays during panoramic dental radiographies. MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2004; 562:111-7. [PMID: 15279834 DOI: 10.1016/j.mrgentox.2004.05.008] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2003] [Revised: 05/17/2004] [Accepted: 05/21/2004] [Indexed: 11/19/2022]
Abstract
The genotoxic effects of X-ray emitted during dental panoramic radiography were evaluated in exfoliated cells from oral epithelium through a differentiated protocol of the micronucleus test. Thirty-one healthy individuals agreed to participate in this study and were submitted to this procedure for diagnosis purpose after being requested by the dentist. All of them answered a questionnaire before the examination. Cells were obtained from both sides of the cheek by gentle scrapping with a cervical brush, immediately before the exposure and after 10 days. Cytological preparations were stained according to Feulgen-Rossenbeck reaction and analyzed under light and laser scanning confocal microscopies. Micronuclei, nuclear projections (buds and broken eggs) and degenerative nuclear alterations (condensed chromatin, karyolysis and karyorrhexis) were scored. The frequencies of micronuclei, karyolysis and pycnosis were similar before and after exposure (P > 0.90), whereas the condensation of the chromatin and the karyorrhexis increased significantly after exposure (P < 0.0001). In contrast, both bud and broken egg frequencies were significantly higher before the examination (P < 0.005), suggesting that these structures are associated to the normal epithelium differentiation. The results suggest that the X-ray exposure during panoramic dental radiography induces a cytotoxic effect by increasing apoptosis. We also believe that the score of other nuclear alterations in addition to the micronucleus improves the sensitivity of genotoxic effects detection.
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215
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Pereira CM, de Andrade CR, Vargas PA, Coletta RD, de Almeida OP, Lopes MA. Dental Alterations Associated with X-Linked Hypophosphatemic Rickets. J Endod 2004; 30:241-5. [PMID: 15085056 DOI: 10.1097/00004770-200404000-00015] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The X-linked hypophosphatemic rickets is a rare metabolic disorder characterized by low serum phosphate levels caused by a decreased renal tubular reabsorption of inorganic phosphates. The initial complaints are a delay in the development of walking caused by deformity of the legs. Oral findings include poorly mineralized dentin, enlarged pulp chambers and root canals, and periradicular abscesses in caries-free teeth. We present three patients from the same family with X-linked hypophosphatemic rickets showing bone and dental alterations.
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216
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Pires FR, Sagarra R, Corrêa MEP, Pereira CM, Vargas PA, Lopes MA. Oral metastasis of a hepatocellular carcinoma. ORAL SURGERY, ORAL MEDICINE, ORAL PATHOLOGY, ORAL RADIOLOGY, AND ENDODONTICS 2004; 97:359-68. [PMID: 15024361 DOI: 10.1016/s1079210403006127] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
Hepatocellular carcinoma is a relatively common tumor that etiologically is closely linked to previous hepatitis B infection. Oral metastatic hepatocellular carcinoma is very rare, with only 61 cases reported in the literature. We describe a case of hepatocellular carcinoma metastatic to the anterior mandibular gingivae of a 60-year-old man. The patient also exhibited tumor metastases to the lungs, left knee, little finger of the left hand, scalp, and the skin of the neck. He died 6 months after the diagnosis of the oral metastasis because of systemic tumor dissemination.
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217
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Pires FR, Paes de Almeida O, Lopes MA, Elias da Cruz Perez D, Kowalski LP. Central mucoepidermoid carcinoma of the mandible: report of four cases with long-term follow-up. Int J Oral Maxillofac Surg 2003; 32:378-82. [PMID: 14505620 DOI: 10.1054/ijom.2002.0374] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Central mucoepidermoid carcinomas are uncommon tumours, representing about 2 to 4% of all mucoepidermoid carcinomas. They are histologically low-grade cancers, usually affecting the mandible as uni- or multilocular radiographic lesions. The authors report four cases of central mucoepidermoid carcinomas affecting the mandible and discuss their clinical, radiographic and histological findings. Four females were affected, with a mean age of 42 years and all cases involved the posterior mandible. Treatment included surgery in three cases and surgery associated to neck dissection and radiotherapy in one case. Two patients showed no recurrence and were alive without signs of the disease after a mean follow-up of 78 months. The other two patients showed local recurrence and one was alive with disease after a follow-up of 384 months, and the other was followed-up for 324 months dying by other causes without signs of the tumour. Central mucoepidermoid carcinomas of the mandible are low-grade tumours, and effective surgical treatment involving wide local excision or en bloc resection allows patients to have a favourable prognosis after long-term follow-up.
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218
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Junior AT, de Abreu Alves F, Pinto CAL, Carvalho AL, Kowalski LP, Lopes MA. Clinicopathological and immunohistochemical analysis of twenty-five head and neck osteosarcomas. Oral Oncol 2003; 39:521-30. [PMID: 12747978 DOI: 10.1016/s1368-8375(03)00017-4] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The aim of this study was to analyze the clinicopathological features and immunohistochemical expression of p53, MDM2, CDK4, PCNA and Ki67 proteins in 25 head and neck osteosarcomas registered in a single institution. The mean age of the patients was 29 years and the most common site was the mandible (60%). The predominant histological type was the chondroblastic (72%) and 52% of the cases were classified as intermediate-grade of malignancy. The immunohistochemical analysis displayed positivity in 52% of the cases for p53, 24% for MDM2, 84% for CDK4, 92% for PCNA and 88% for Ki-67. The majority of cases were treated with surgery alone or associated with chemotherapy. Five patients developed local recurrences, four had distant metastasis and six had persistent disease after initial treatment. The overall 5-year and 10-year survival rates were 59% and 49%, respectively, and the most important prognostic factors were prior history of radiation exposure and osteoblastic histological type.
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219
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Bonan PRF, Pires FR, Lopes MA, Di Hipólito O. Evaluation of salivary flow in patients during head and neck radiotherapy. ACTA ACUST UNITED AC 2003; 17:156-60. [PMID: 14569359 DOI: 10.1590/s1517-74912003000200011] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Radiotherapy is frequently employed for the treatment of head and neck squamous cell carcinoma. Among the side effects, xerostomia is one of the most important. With the objective of evaluating the role of radiotherapy in salivary flow, we performed three salivary sample collections: at the beginning of, during, and immediately after radiotherapy. The results showed that the salivary flow values of the first collection were very similar to those of the control group. However, during treatment, there was a significant decrease of the salivary flow (p = 0.0008), which continued low immediately after radiotherapy (p = 0.0009). Our study showed that radiotherapy leads to an important reduction of salivary flow during and after radiotherapy.
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220
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Pires FR, Alves FDA, de Almeida OP, Lopes MA, Kowalski LP. Synchronous mucoepidermoid carcinoma of tongue and pleomorphic adenoma of submandibular gland. ORAL SURGERY, ORAL MEDICINE, ORAL PATHOLOGY, ORAL RADIOLOGY, AND ENDODONTICS 2003; 95:328-31. [PMID: 12627105 DOI: 10.1067/moe.2003.7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Presentation with synchronous salivary gland tumors is rare, with the most typical combination being Warthin's tumor and pleomorphic adenoma of the parotid gland. Involvement of minor salivary glands in such occurrences is extremely uncommon. We report a case of simultaneous mucoepidermoid carcinoma of the tongue and pleomorphic adenoma of the submandibular gland in a 40-year-old woman. The submandibular mass was initially considered to represent regional lymph node tumor metastasis but later was shown to be an intraglandular primary neoplasm.
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221
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Abstract
Metastases of osteosarcoma in the mouth are rare, and only few cases have been described. We present a case of telangiectatic osteosarcoma of the femur in a 15-year-old girl, who developed metastases in the humerus, lungs and retromolar area 4 years after initial diagnosis and treatment. The girl died 2 months after the diagnosis of metastases despite treatment with chemotherapy. This report emphasizes that telangiectatic osteosarcoma has a very poor prognosis, particularly when multiple metastases develop.
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222
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Fregnani ER, Pires FR, Falzoni R, Lopes MA, Vargas PA. Lipomas of the oral cavity: clinical findings, histological classification and proliferative activity of 46 cases. Int J Oral Maxillofac Surg 2003; 32:49-53. [PMID: 12653233 DOI: 10.1054/ijom.2002.0317] [Citation(s) in RCA: 224] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Lipomas represent about 1 to 5% of all neoplasms of the oral cavity. Although relatively common, few large series of intraoral lipomas and its variants are seen in the literature. Therefore, the authors present the clinical, histological and immunohistochemical features of 46 cases of intraoral lipomas reviewed from the files of the University of Campinas Dental School from 1970 to 2001. Most of the cases affected adults, without gender predilection, and the main involved sites were the buccal mucosa (21 cases), tongue (six cases), lips (six cases) and floor of mouth (five cases). The histological analysis revealed 21 cases of lipoma, 18 fibrolipomas, four intramuscular lipomas, two minor salivary gland lipomas and one spindle cell lipoma. PCNA and ki-67 expression indexes were higher in spindle cell lipoma, intramuscular lipomas and fibrolipomas compared to common lipomas, but the differences were not statistically significant. All lesions were removed surgically and none showed recurrence, regardless of the various proliferative activities.
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223
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Amaral M, Costa MA, Lopes MA, Silva RF, Santos JD, Fernandes MH. Si(3)N(4)-bioglass composites stimulate the proliferation of MG63 osteoblast-like cells and support the osteogenic differentiation of human bone marrow cells. Biomaterials 2002; 23:4897-906. [PMID: 12361631 DOI: 10.1016/s0142-9612(02)00249-1] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The in vitro osteocompatibility of a novel Si(3)N(4)-bioglass composite (70-30% weight proportion) with improved mechanical properties (fracture toughness = 4.4 M Pa m(1/2); bending strength = 383 +/- 47 MPa) is reported. Immersion of the composite samples in culture medium (30 min to 7 days) resulted in rapid protein adsorption to the surface and, also, dissolution of the intergranular phase of bioglass (time-dependent process) with the formation of different size cavities. "As-received" and pre-treated material samples presented a similar behaviour concerning the proliferation of MG63 osteoblast-like cells, evaluated during a 5-day culture period. Seeded materials showed a higher cell growth rate as compared to cultures performed on the standard plastic culture plates. To assess the osteogenic potential of the composite, "as-received" material samples were seeded with human bone marrow cells and cultured for 35 days in experimental conditions that favour the development of the osteoblastic phenotype. The cell adhesion process was similar to that observed in control cultures. Cells successfully adapted to the irregularities of the surface and were able to grow towards inside the cavities; in addition, osteogenic differentiation occurred with the formation of abundant cell-mediated mineralised deposits. Results suggest that this Si(3)N(4)-bioglass composite seems to be a promising candidate for high-stress medical applications.
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Botelho CM, Lopes MA, Gibson IR, Best SM, Santos JD. Structural analysis of Si-substituted hydroxyapatite: zeta potential and X-ray photoelectron spectroscopy. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2002; 13:1123-1127. [PMID: 15348653 DOI: 10.1023/a:1021177601899] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The aim of this study was to determine the effect of the incorporation of silicon on the surface charge of hydroxyapatite (HA) and to assess surface structural changes of HA and Si-HA induced by dissolution in both static and dynamic systems. X-ray photoelectron spectroscopy (XPS) analysis showed that SiO(4)(4-) groups were substituted for PO(4)(3-) groups in the silicon-hydroxyapatite (Si-HA) lattice according to a previously proposed substitution mechanism without the formation of other crystalline phases, such as tricalcium phosphate or calcium oxide. The substituted silicon induced a decrease in the net surface charge and the isoelectric point of HA as determined by zeta potential (ZP) measurements. At physiological pH=7.4 the surface charge of Si-HA was significantly lowered compared to unmodified HA, i.e. -50+/-5 to -71+/-5 eV, caused by the presence of silicate groups in the HA lattice, which may account for a faster in vitro apatite formation using SBF testing. XPS results indicated that silicon seems to be preferentially leached out from Si-HA surface compared to other ionic species after dissolution studies in tris-buffer using a dynamic system.
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Pires FR, Santos EBD, Bonan PRF, De Almeida OP, Lopes MA. Denture stomatitis and salivary Candida in Brazilian edentulous patients. J Oral Rehabil 2002; 29:1115-9. [PMID: 12453267 DOI: 10.1046/j.1365-2842.2002.00947.x] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Denture stomatitis (DS) is frequently associated with high levels of Candida in saliva and deficient denture hygiene. In order to analyse the incidence of DS and its pre-disposing factors, we evaluated 77 edentulous patients before and 6 months after the placement of new complete dentures. Denture stomatitis was observed in 50.6 and 18.2% of the patients at the first and second evaluation, respectively. Salivary flow, Candida counts in saliva and Candida species were similar in both evaluations. Denture stomatitis and Candida in saliva were more common in females. Our results showed that denture replacement and denture hygiene improvement were useful for DS resolution, particularly types I and II. However, oral and denture hygiene must be continuous, inasmuch as salivary Candida counts remained high and it is considered an important pre-disposing factor for DS.
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Amaral M, Lopes MA, Santos JD, Silva RF. Wettability and surface charge of Si3N4-bioglass composites in contact with simulated physiological liquids. Biomaterials 2002; 23:4123-9. [PMID: 12182314 DOI: 10.1016/s0142-9612(02)00155-2] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Wettability and surface charge studies were performed on a novel Si3N4-30wt% bioglass biocomposite. Contact angle and surface tension variation with time were determined at 25 degrees C, respectively, by the sessile and pendant drop techniques, for distinct testing liquids: water, diiodomethane, simulated body fluid (SBF) and bovine serum albumin (BSA) dissolved in SBF solution. This biocomposite revealed a hydrophilic character (theta = 26.6 +/- 2.0 degrees) and a surface tension value (66.6 mJ m(-2)) comparatively higher than those of the most common bioceramics. An important characteristic is the high work of adhesion towards SBF + BSA (96.4 +/- 0.2mJ m(-2)) that was measured. The Si3N4-bioglass material is negatively surface charged above the pH(IEP) = 2.5 in aqueous SBF + BSA solution, as a result of the presence at the surface of unsaturated Si-O bonds and Si-OH groups. The very high negative zeta potential at pH approximately 7 (-58.6 +/- 5.5mV) influenced albumin adsorption and mechanisms are discussed in terms of entropy and enthalpy gains from conformational unfolding and cations coadsorption.
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Hargreaves BJ, Kronfeld DS, Waldron JN, Lopes MA, Gay LS, Saker KE, Cooper WL, Sklan DJ, Harris PA. Antioxidant status and muscle cell leakage during endurance exercise. Equine Vet J 2002:116-21. [PMID: 12405670 DOI: 10.1111/j.2042-3306.2002.tb05402.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Antioxidant status of 35 endurance horses was studied during an 80 (OD80) or 160 km (OD160) race. Packed cell volume (PCV), total plasma protein (TPP), plasma ascorbic acid (VIT C), plasma alpha-tocopherol (VIT E) and erythrocyte glutathione (GSH) concentrations, erythrocyte glutathione peroxidase (GPX), plasma aspartate aminotransferase (AST) and plasma creatine kinase (CK) activities were measured at 0, 40, 80 km and 60 min of recovery (REC) at OD80, and 0, 64, 106, 142, 160 km and REC at OD160. In both races, no changes were found in plasma VIT E concentration, but VIT C and GSH concentrations decreased (P<0.05), and mean GPX, AST and CK activities increased from 0 km (P<0.05). Indices of muscle cell leakage (plasma AST and CK) were correlated (r = 0.36 to 0.67; P<0.03) with indices of antioxidant status (VIT C, GSH and GPX). Associations between increased muscle leakage and decreased antioxidant status may, in part, reflect oxidative stress and suggest the testing of antioxidant supplements in endurance horses to improve performance and welfare.
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Jorge J, Pires FR, Alves FA, Perez DEC, Kowalski LP, Lopes MA, Almeila OP. Juvenile intraoral pleomorphic adenoma: report of five cases and review of the literature. Int J Oral Maxillofac Surg 2002; 31:273-5. [PMID: 12190133 DOI: 10.1054/ijom.2002.0206] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The aim of this study is to report on five cases of intraoral pleomorphic adenoma (PA) in patients under 18 years of age and to review the literature. Intraoral salivary gland tumours were reviewed in two Brazilian institutions and five cases of PA in patients under 18 years of age were found. Clinical data were obtained from the medical records and paraffin-embedded tissues were sectioned for proliferating cell nuclear antigen (PCNA) and p53 immunohistochemical analysis. Four patients were female and one was male; two cases affected the palate, two the upper lip and one the tongue. All five patients were treated surgically and after long follow-up periods no recurrences were observed. Tumour cells were weakly positive for PCNA and negative for p53. PA should be considered in the differential diagnosis of submucosal nodules in young patients. In youngsters, PA seems to have similar biological characteristics as in adults, with low recurrence rates after surgical resection.
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Vargas PA, Alves FA, Lopes MA, Siqueira SAC, Menezes LFC, Aldred VL, Almeida OP. Solitary fibrous tumour of the mouth: report of two cases involving the tongue and cheek. Oral Dis 2002; 8:111-5. [PMID: 11991306 DOI: 10.1034/j.1601-0825.2002.1c769.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
We describe two additional cases of solitary fibrous tumour (SFT) affecting the mouth. SFT is very uncommon in the oral cavity and we found only 14 cases reported in the literature. Our two cases were well circumscribed, slow growing tumours that, after surgical removal, did not recur. Case 1 was a 3 cm nodule on the right cheek. Hypo and hypercellular adjacent areas were mainly patternless, and the stroma was formed by thin collagen fibrils. Case 2 was a 4.8 cm mass in the anterior portion of the tongue. Microscopically it was formed by spindle cells embedded in a vascularized sclerotic collagen matrix. Some areas were hypercellular with scarce collagen fibrils. The immunohistochemical findings were similar in both cases, with strong immunoreactivity for vimentin, CD34, bcl-2, focal positivity for Ki-67 and negativity for other immunomarkers. Based on these clinical, microscopical and immunohistochemical features the final diagnosis of these two cases was SFT. Diagnosis of SFT is difficult and, although uncommon, it should be considered in the differential diagnosis of oral soft tissue tumours.
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Lopes MA, Nikitakis NG, Reynolds MA, Ord RA, Sauk J. Biomarkers predictive of lymph node metastases in oral squamous cell carcinoma. J Oral Maxillofac Surg 2002; 60:142-7; discussion 147-8. [PMID: 11815908 DOI: 10.1053/joms.2002.29804] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE The ability of oral squamous cell carcinoma to metastasize to lymph nodes does not always show a relationship with clinical staging. The aim of this study was to attempt to define a trend for predictive histopathologic and/or molecular biomarkers in the development of nodal metastasis by analyzing 2 clinically extreme groups. PATIENTS AND METHODS Patients with small primary tumors (T1, T2) with lymph node metastasis and patients with large primary tumors (T3, T4) without metastatic disease were identified among 315 consecutive cases of primary oral squamous cell carcinoma. Group comparisons were made with use of a Mann-Whitney test, and associations among the variables were assessed with nonparametric and parametric correlational analyses. RESULTS The degree of keratinization was significantly less in primary tumors with lymph node metastasis (P < or = .01). The degree of keratinization was significantly associated with nuclear pleomorphism (P =.02), number of mitoses (P =.02), stage of invasion (P =.002), and p53 expression (P =.04), independent of clinical stage of the tumor. Other microscopic features and immunohistochemical markers did not differ significantly between the groups (P >.05). CONCLUSION These data indicate that there still is no single predictive parameter superior to the degree of keratinization to identify patients at risk for the development of regional metastasis.
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Amaral M, Lopes MA, Silva RF, Santos JD. Densification route and mechanical properties of Si3N4-bioglass biocomposites. Biomaterials 2002; 23:857-62. [PMID: 11771704 DOI: 10.1016/s0142-9612(01)00194-6] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The processing route and the final microstructural and mechanical characteristics of a novel biomaterial composite are described. This new material is composed of 70 wt% Si3N4 ceramic phase and 30 wt% bioglass, the later performing as a liquid sintering aid system and simultaneously providing bioactivity characteristics to the composite. The conditions for fabrication of an almost fully dense material (approximately 98% of relative density) were pursued. Optimised parameters were 1350 degrees C-40 min-30 MPa by hot-pressing technique. The very fast densification rate of the process avoided the crystallisation of the bioglass intergranular phase and therefore its intrinsic properties were maintained. Also, the large amount of glassy phase assured the densification by liquid phase assisted grain rearrangement without Si3N4 phase transformation. The final mechanical properties of the Si3N4 bioglass were as follows: fracture toughness, K(IC) = 4.4 MPa m(1/2); Vickers hardness, Hv = 10.3 GPa; Young's modulus, E = 197 GPa; bending strength, sigma(g) = 383 MPa; Weibull modulus, m = 8.3. These values provide an attractive set of properties among other bioactive materials, namely by upgrading the main drawback of bioceramcs and bioglasses for high-load medical applications, which is the lack of satisfactory fracture toughness.
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232
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Ribeiro A, Moura P, Azevedo L, Ferrão B, Marques A, Lopes MA. [Uncomplicated acute myocardial infarction -- when should the patient be discharged?]. Rev Port Cardiol 2001; 20:1103-6. [PMID: 11826701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
INTRODUCTION AND OBJECTIVES Hospital discharge on day 10 after acute myocardial infarction (AMI) is still frequent in our hospital. The present study aims at evaluating the occurrence of cardiac events on day 5, 7 and 10, in patients with AMI who had an uncomplicated course for 72 hours after thrombolysis, as well as a cost-effectiveness analysis on an earlier discharge. METHODS We retrospectively studied consecutive patients admitted with AMI for a period of 5 years, submitted to thrombolysis who suffered no events (recurrent ischemia, reinfarction, coronary revascularization, heart failure, arrhythmias implicating electric cardioversion or dysfibrilation, pacemaker or death) within the first 72 hours (n = 128; 101 males and 27 females, mean age 64.1 +/- 12.8). Patients were divided into two groups, with no events occurring by discharge (group I, n = 119) or with events between 72 hours and discharge (group II, n = 9). The latter were subdivided according to whether events occurred between 72 hours and day 5, between days 6 and 7 or between 8 and 10. RESULTS Group I and II were not significantly different regarding vascular risk factors, prior coronary disease and infarction location. Group I was mainly constituted of males, younger than those in group II and with preserved systolic LV function. Between 72 hours and discharge, there were no events in 93% of the patients (119) and events occurred in 7% (9 patients). Two cases of cardiac events occurred until day 5 (1.6%) one angina and one death, two patients with complications between days 6 and 7 (1.6%), both heart failure, and 5 patients suffered events after day 7 (4%), 3 angina and 2 deaths. Dead patients (3 cases--2.3%) were older, had prior AMI, mostly with unpreserved systolic LV function and prior ischemic heart disease. All of them had sudden death. The most frequent non-fatal complications were recurrent ischemia and heart failure. CONCLUSIONS AND IMPLICATIONS In patients with AMI who had an uncomplicated course for 72 hours after thrombolysis, the risk of cardiac events by the 10th day is low. It occurs randomly in time. In this group of patients it seems of no effectiveness to lengthen hospitalization. An earlier discharge may be advantageous since it does not significantly increase the risk that a longer hospitalization could prevent.
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Lopes MA. [Not Available]. REVISTA PORTUGUESA DE HISTORIA 2001; 21:119-76. [PMID: 11635827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
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Lopes MA, Nikitakis NG, Ord RA, Sauk J. Amplification and protein expression of chromosome 12q13-15 genes in osteosarcomas of the jaws. Oral Oncol 2001; 37:566-71. [PMID: 11564577 DOI: 10.1016/s1368-8375(00)00130-5] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Overexpression and amplification of several genes (MDM2, CDK4 and SAS) located on chromosome 12q13-15 have been noted to occur in various human sarcomas. As a result, two major growth regulation pathways may be inhibited. MDM2 may down regulate the p53-mediated growth control and CDK4 may affect pRB-mediated events. To determine the frequency of alterations in these genes and their correlation with clinicopathologic features, we analyzed the MDM2 and CDK4 protein levels by immunohistochemistry and assessed MDM2, CDK4 and SAS amplification by real-time PCR in nine osteosarcomas of the jaws. Positive staining for CDK4 and MDM2 was observed in eight cases (88.8%) and five cases (55.5%), respectively. Intense CDK4 staining was noted in four cases (two high grade, one intermediate grade and one low grade). Intense MDM2 staining was observed in the same four previous cases, as well as, one additional high-grade tumor. Individual DNA amplification for CDK4, MDM2 and SAS was observed in six cases for each gene. Co-amplification was observed in five cases that showed CDK4 and MDM2 concomitant amplification and four cases that displayed amplification for all of the genes. In addition, among the five cases that presented CDK4 and MDM2 amplification, strong overexpression of CDK4 and MDM2 was observed in three and in four cases, respectively (three high grade and one intermediate grade). These results suggest that 12q13-15 genes are involved in neoplastic disease and concurrent amplification and overexpression of these genes might help to define high-grade tumors.
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Nikitakis NG, Lopes MA, Pazoki AE, Ord RA, Sauk JJ. MDM2+/CDK4+/p53+ oral liposarcoma: case report and review of the literature. ORAL SURGERY, ORAL MEDICINE, ORAL PATHOLOGY, ORAL RADIOLOGY, AND ENDODONTICS 2001; 92:194-201. [PMID: 11505267 DOI: 10.1067/moe.2001.116815] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Although liposarcoma is one of the most common soft tissue sarcomas, its location in the oral cavity is very rare. To our knowledge, only 43 cases of liposarcoma originating in the oral tissues have been reported in the English-language literature. In this article, we report a case of well-differentiated liposarcoma affecting the cheek of a 28-year-old man and review the oral liposarcoma literature. Immunohistochemical analysis of the tumor revealed an MDM2+/CDK4+/p53+ immunophenotype that is consistent with the immunohistochemical profile of well-differentiated liposarcoma originating in other areas of the body. Quantitative polymerase chain reaction analysis of the DNA levels of the MDM2 (human homologue of the murine double-minute type 2), CDK4 (cyclin-dependent kinase 4), and SAS (sarcoma amplified sequence), genes was performed, revealing only SAS gene amplification. The possibility of misdiagnosis of oral liposarcoma because of its sometimes inconspicuous clinical and microscopic features is emphasized. Careful pathologic examination of liposarcoma is essential for discrimination from benign adipose tissue neoplasms and for precise histologic classification, both of major prognostic significance. Possible implications of molecular and cytogenetic analysis for unraveling the pathogenesis and determining the prognosis of liposarcoma are discussed.
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Bozzo L, Machado MA, de Almeida OP, Lopes MA, Coletta RD. Hereditary gingival fibromatosis: report of three cases. J Clin Pediatr Dent 2001; 25:41-6. [PMID: 11314351 DOI: 10.17796/jcpd.25.1.e254616x22403280] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
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.
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Lopes MA, de Abreu Alves F, Levy BA, de Almeida OP, Kowalski LP. Intraoral salivary duct carcinoma: case report with immunohistochemical observations. ORAL SURGERY, ORAL MEDICINE, ORAL PATHOLOGY, ORAL RADIOLOGY, AND ENDODONTICS 2001; 91:689-92. [PMID: 11402284 DOI: 10.1067/moe.2001.115028] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Salivary duct carcinoma is an uncommon malignant salivary gland tumor that occurs predominantly in the parotid gland. Oral involvement is extremely rare, with few cases having been reported in the literature. The tumor is characterized by an aggressive behavior and has a poor prognosis. We describe a case of salivary duct carcinoma arising in the hard palate of a 63-year-old man. Immunohistochemical analysis revealed that tumor cells tested positive for cytokeratin, epithelial membrane antigen, proliferating cell nuclear antigen, Ki67, p53, laminin, and collagen IV. Despite radical surgical resection, bilateral neck dissection, and postoperative radiotherapy, liver metastases developed, and the patient subsequently died of his disease.
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Lopes MA, Ruano R, Bunduki V, Miyadahira S, Zugaib M. Prenatal diagnosis and follow up of congenital splenic cyst: a case report. ULTRASOUND IN OBSTETRICS & GYNECOLOGY : THE OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY OF ULTRASOUND IN OBSTETRICS AND GYNECOLOGY 2001; 17:439-441. [PMID: 11380971 DOI: 10.1046/j.1469-0705.2001.00401.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
We report a case of congenital splenic cyst that was identified by prenatal sonography at 25 gestational weeks. Serial scans demonstrated an increase in size during the prenatal period but after birth the cyst progressively decreased in size until its complete regression at 6 months of age.
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Lopes MA, Santos JD, Monteiro FJ, Ohtsuki C, Osaka A, Kaneko S, Inoue H. Push-out testing and histological evaluation of glass reinforced hydroxyapatite composites implanted in the tibia of rabbits. JOURNAL OF BIOMEDICAL MATERIALS RESEARCH 2001; 54:463-9. [PMID: 11426590 DOI: 10.1002/1097-4636(20010315)54:4<463::aid-jbm10>3.0.co;2-y] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In vitro and in vivo bioactivity studies were performed to assess the biocompatibility of CaO-P2O5 glass-reinforced hydroxyapatite (GR-HA) composites. The ability to form an apatite layer by soaking in simulated body fluid (SBF) was examined and surfaces were characterized using FTIR reflection and thin-film X-ray diffraction analyses. Qualitative histology, histomorphometric measurements, and push-out testing were performed in a rabbit model for characterizing bone/implant bonding. Under the in vitro conditions using SBF, an apatite layer could not be formed on GR-HA composites within 8 weeks. Results of push-out testing showed bonding between the composites and bone, ranging from 130-145 N after 2 weeks of implantation. After the longest implantation period, 16 weeks, the GR-HA composite prepared with the higher content of CaO-P2O5 glass showed the highest bonding force, 606 +/- 45 N, compared to 459 +/- 30 N for sintered HA. Development of immature bone and modifications in the turnover of a more mature bone on the surface of GR-HA composites were similar to those on sintered HA.
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Forato LA, Colnago LA, Garratt RC, Lopes MA. Identification of free fatty acids in maize protein bodies and purified alpha zeins by (13)C and (1)H nuclear magnetic resonance. BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1543:106-14. [PMID: 11087946 DOI: 10.1016/s0167-4838(00)00190-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Zeins, the maize storage proteins, are the most abundant proteins in the corn endosperm, and are synthesized on the rough endoplasmatic reticulum and deposited in discrete organelles called protein bodies. Several authors, using circular dichroism and optical rotatory dispersion, have concluded that these proteins have a high alpha-helical content in alcoholic solution. In this work we have studied these proteins, within the protein bodies themselves and after extraction from the corn grains with 70% ethanol, using NMR (nuclear magnetic resonance) spectroscopy. We conclusively demonstrate the presence of free fatty acids within both the protein bodies and also in the alcohol extracted alpha zeins. We present evidence for a direct interaction between the free fatty acids and the alpha zein proteins within the protein body and suggest possible mechanisms by which such an association has arisen during the evolution of the maize endosperm.
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Lopes MA, Pazoki AE, Ord RA. Proliferative verrucous leukoplakia: a case report. GENERAL DENTISTRY 2000; 48:708-10. [PMID: 12004667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
Proliferative verrucous leukoplakia (PVL) is a particularly aggressive form of oral leukoplakia that is resistant to treatment and presents a high risk of recurrence and malignant transformation. This article describes the microscopic and clinical characteristics of one case of PVL, which initially presented as hyperkeratosis with mild dysplasia and posteriorly developed multifocal areas and verrucous carcinoma despite treatment.
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Lopes MA. [Polemic in fetal echocardiography: has the "golf-ball" sign any clinical significance?]. Rev Assoc Med Bras (1992) 2000; 46:298. [PMID: 11175551 DOI: 10.1590/s0104-42302000000400015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Lopes MA, Pfeiffer CJ. Functional morphology of the equine pelvic flexure and its role in disease. A review. Histol Histopathol 2000; 15:983-91. [PMID: 10963140 DOI: 10.14670/hh-15.983] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The hindgut is the major site in the horse for nutrient digestion and absorption. Most of this activity occurs in the large intestinal compartments, i.e., cecum, right and left ventral colon and left and right dorsal colon. The colonic pelvic flexure is a short and narrow loop connecting the left ventral and left dorsal colon. It is not significant directly in digestive and absorptive processes but plays an important functional role in regulating colonic aboral and retropropulsive transit of digesta through its motility pacemaker activity. The pelvic flexure also contributes to the pathophysiology of colic, the leading cause of death in horses. Its narrow lumen may contribute to colonic impaction, and malfunctions of the pacemaker may contribute to volvuli and colonic displacements. Neuronal and ganglion density of the myenteric plexus is increased at the pelvic flexure and adjacent left dorsal colon pacemaker region. Contractile activity, vasoactive intestinal peptide (VIP) and neurokinins-1 and -3 are all enhanced in the pelvic flexure. The mucosa histologically resembles that of the ventral and dorsal colon, with apically-granulated principal cells and goblet cells lining the luminal surface. Clustered intranuclear inclusions resembling the cytoplasmic granules are also observed by electron microscopy in the principal cells as elsewhere in the horse colon. Further neuroendocrine and morphologic investigation of the pelvic flexure is warranted due to the great importance of this localized region for normal function and pathophysiology.
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Lopes MA, Silva RF, Monteiro FJ, Santos JD. Microstructural dependence of Young's and shear moduli of P2O5 glass reinforced hydroxyapatite for biomedical applications. Biomaterials 2000; 21:749-54. [PMID: 10711972 DOI: 10.1016/s0142-9612(99)00248-3] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
P2O5 glass reinforced hydroxyapatite composite materials were prepared through a liquid-phase sintering process. Secondary phases, beta- and alpha-tricalcium phosphates (beta-TCP and alpha-TCP), were formed in the microstructure of the composites, due to the reaction between the liquid glassy phase and the hydroxyapatite matrix. The dynamic Young's modulus (E) and shear modulus (G) of these composites were determined using an impulse excitation method. By applying the Duckworth-Knudsen equation, the elastic property results were correlated with the relative proportion of beta-TCP and alpha-TCP phases and with the porosity percentage present in the microstructure. Glass reinforced hydroxyapatite composites showed lower Young's and shear moduli than unmodified hydroxyapatite, mainly due to the presence of beta-TCP phase. The Duckworth-Knudsen model demonstrated an exponential dependence of E and G modulus with porosity and mathematical equations were derived for composite materials with porosity correction factors (b) of 4.04 and 4.11, respectively, indicating that porosity largely decreased both E and G moduli.
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Lopes MA, Goncalves M, Di Hipolito Júnior O, de Almeida OP. Congenital lower lip pits: case report and review of literature. J Clin Pediatr Dent 2000; 23:275-7. [PMID: 10686876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/15/2023] Open
Abstract
A case of congenital lower lip pits is presented. The main characteristics of these malformations, the importance of the diagnosis and the surgical treatment are discussed.
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Pires FR, Ferraz CC, Alves FDA, Lopes MA, de Almeida OP. Pemphigus vulgaris in adolescence: case report. Pediatr Dent 2000; 22:159-62. [PMID: 10769865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Pemphigus vulgaris is an uncommon mucocutaneous disease caused by autoantibodies against desmosomal antigens. It affects mainly middle-aged adults, and juvenile cases are rare. The authors present a case of pemphigus vulgaris in adolescence and review the literature. A 16-year-old girl showed oral and cutaneous lesions suggestive of pemphigus vulgaris. Histopathology and direct immunofluorescence of the oral mucosa confirmed the diagnosis and systemic steroid therapy was efficient in controlling the disease. The recognition of the oral lesions of pemphigus by the clinician, its early diagnosis, and prompt therapy are essential for a favorable prognosis.
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Pfeiffer CJ, Levin M, Lopes MA. Ultrastructure of the horse tongue: further observations on the lingual integumentary architecture. Anat Histol Embryol 2000; 29:37-43. [PMID: 10820901 DOI: 10.1046/j.1439-0264.2000.00232.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
This investigation examined primarily epidermal specializations of the adult horse tongue by light, scanning and transmission electron microscopy. Samples were collected from seven regions of the normal tongue of various breeds of horse. The filiform papillae, present on the dorsal and lateral aspects but not the ventral aspect of the tongue, were short, slender and finger-like structures with variable-shaped terminae. The epidermal thickness and height of dermal ridges were reduced on fungiform and vallate papillae, but tissue architecture and keratinocyte ultrastructure of most of the lingual epidermis corresponded to the common mammalian epidermal paradigm. One unique finding was the highly localized clustering of epidermal cells with exceptionally high content of PAS-negative trichohyalin cytoplasmic granules at a location atop the dermal ridges and beneath the base of filiform papillae. These granular cells were immediately subjacent to clusters of clear, non-granulated epidermal cells. It is believed that this integumentary specialization may enhance the structural strength at this localized site of the tissue architecture, in relationship to the mechanical papillae.
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Lopes MA, Barbosa CR, Gomes BP, Di Hipólito Junior O, de Almeida OP. An unusual alteration in the shape of a tooth. GENERAL DENTISTRY 2000; 48:100-2. [PMID: 11199543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
Dental anomalies are an important issue and dentists should be able to manage these conditions. Often, treatment is not necessary; however, some abnormalities may affect the esthetics or function of teeth and can lead to other problems. This case report presents an unusual case of alteration in shape affecting the left lower canine in a 34-year-old woman.
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Lopes MA, Monteiro FJ, Santos JD. Glass-reinforced hydroxyapatite composites: fracture toughness and hardness dependence on microstructural characteristics. Biomaterials 1999; 20:2085-90. [PMID: 10535820 DOI: 10.1016/s0142-9612(99)00112-x] [Citation(s) in RCA: 100] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Fracture toughness and hardness properties of CaO-P2O5 glass-reinforced hydroxyapatite composites have been assessed using indentation techniques and results calculated according to Laugier and Evans' equations. Both properties showed to be dependent upon several microstructural characteristics, namely residual porosity and the percentage of secondary beta and alpha tricalcium phosphate phases in the structure of the composites. Composites presented a Palmqvist-type indentation crack system, which is the specific crack system addressed by Laugier's approach. Fracture toughness determinations according to Evan's equation, which is a universal one and adapted to both median and Palmqvist crack systems, did not correlate well with Laugier determinations.
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Lopes MA, Monteiro FJ, Santos JD. Glass-reinforced hydroxyapatite composites: secondary phase proportions and densification effects on biaxial bending strength. JOURNAL OF BIOMEDICAL MATERIALS RESEARCH 1999; 48:734-40. [PMID: 10490690 DOI: 10.1002/(sici)1097-4636(1999)48:5<734::aid-jbm20>3.0.co;2-2] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
CaO-P(2)O(5) glasses with additions of MgO and CaF(2) were used as a sintering aid of hydroxyapatite, and glass-reinforced hydroxyapatite composites obtained. Glasses promoted significant changes in the microstructure of the composites, namely with the formation of tricalcium phosphate secondary phases, beta and alpha-TCP. Quantitative phase analysis was performed by the Rietveld method using General Structure Analysis Software. Grain size measurements were carried out on SEM photomicrographs, using a planimetric procedure according to ASTM E 112-88. Flexural bending strength was determined from concentric ring-on-ring testing. Flexural bending strength (FBS) of glass-reinforced hydroxyapatite composites was found to be about twice or three times higher than that of unreinforced hydroxyapatite and tended to depend more on porosity and beta and alpha-TCP secondary phases, rather than on grain size. Traces of alpha-tricalcium phosphate significantly enhanced the strength of the composites. Using the rule of mixtures to estimate the zero porosity bending strength, the Duckworth-Knudsen model applied to the composites gave a porosity correction factor, b, with a value of 4.02. Weibull statistics were also used to analyze biaxial strength data and the level of reinforcement obtained by comparing failure probability for the composites and for the unreinforced hydroxyapatite. Lower activation energies for grain growth were observed for the composites compared to unreinforced hydroxyapatite, which should be attributed to the presence of a liquid glassy phase that promotes atomic diffusion during the sintering process.
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