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1.
Med Oral Patol Oral Cir Bucal ; 29(2): e280-e287, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38150606

RESUMO

BACKGROUND: There is no consensus about effective systemic therapy for salivary gland carcinomas (sgcs). Our aim was summarized the clinical trials assessing the systemic therapies (ST) on sgcs. MATERIAL AND METHODS: Electronic searches were carried out through MEDLINE/pubmed, EMBASE, Scopus, Web of Science, and the Cochrane Library databases, and gray literature. RESULTS: Seventeen different drugs were evaluated, and the most frequent histological subtype was adenoid cystic carcinoma (n=195, 45.5%). Stable disease, observed in 11 ST, achieved the highest rate in adenoid cystic carcinoma treated with sunitinib. The highest complete (11.1%) and partial response (30.5%) rates were seen in androgen receptor-positive tumors treated with leuprorelin acetate. CONCLUSIONS: Despite all the advances in this field, there is yet no effective evidence-based regimen of ST, with all the clinical trials identified showing low rates of complete and partial responses. Further, translational studies are urgently required to characterize molecular targets and effective ST.


Assuntos
Carcinoma Adenoide Cístico , Neoplasias das Glândulas Salivares , Humanos , Carcinoma Adenoide Cístico/tratamento farmacológico , Neoplasias das Glândulas Salivares/tratamento farmacológico , Bases de Dados Factuais , Glândulas Salivares
2.
Med Oral Patol Oral Cir Bucal ; 28(4): e301-e309, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37330954

RESUMO

BACKGROUND: To evaluate the prevalence and clinicopathological features of a large series of gingival neoplasms in Brazil. MATERIAL AND METHODS:  All gingival benign and malignant neoplasms were retrieved from the records of six Oral Pathology Services in Brazil, during a 41-year period. Clinical and demographic data, clinical diagnosis, and histopathological data were collected from the patients' clinical charts. For statistical analysis, the chi-square, median test of independent samples and the U Mann-Whitney tests were used, considering a significance of 5%. RESULTS:  From 100,026 oral lesions, 888 (0.9%) were gingival neoplasms. There were 496 (55.9%) males, with a mean age of 54.2 years. Most cases (70.3%) were malignant neoplasms. Nodules (46.2%) and ulcers (38.9%) were the most common clinical appearance for benign and malignant neoplasms, respectively. Squamous cell carcinoma (55.6%) was the most common gingival neoplasm, followed by squamous cell papilloma (19.6%). In 69 (11.1%) malignant neoplasms, the lesions were clinically considered to be inflammatory or of infectious origin. Malignant neoplasms were more common in older men, appeared with larger size, and with a time of complaint shorter than benign neoplasms (p<0.001). CONCLUSIONS:  Benign and malignant tumors may appear as nodules in gingival tissue. In addition, malignant neoplasms, especially squamous cell carcinoma, should be considered in the differential diagnosis of persistent single gingival ulcers.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Gengivais , Úlceras Orais , Masculino , Humanos , Idoso , Pessoa de Meia-Idade , Feminino , Neoplasias Gengivais/patologia , Brasil/epidemiologia , Úlcera/diagnóstico , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/patologia , Diagnóstico Diferencial , Estudos Retrospectivos
3.
Med Oral Patol Oral Cir Bucal ; 28(2): e191-e198, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36565222

RESUMO

BACKGROUND: This study aimed to characterize the barriers faced by Brazilian dentists to deliver bad news (DBN) about oral and oropharyngeal cancer diagnoses to patients by using a questionnaire based on the guidelines of the SPIKES protocol. MATERIAL AND METHODS: This was an observational cross-sectional study. The questionnaire contained 27 questions based on the SPIKES protocol, which were answered in the SurveyMonkey platform. RESULTS: A total of 186/249 dentists answered the questionnaire. The main specialties reported were 36.02% oral medicine, 21.5% oral pathology, and 9.13% oral and maxillofacial surgery. A total of 44.6% expressed concern about the patient's emotional reactions, and 46.24% of respondents had never participated in any specific training to communicate bad news. CONCLUSIONS: The lack of training and low confidence in dealing with patients' emotional reactions dentists were considered the greatest barriers to DBNs. Moreover, most dentists who participated in the survey believe that a protocol to guide the communication of bad news would be useful for clinical practice. For those protocols to be used by dentists, training is critical for these protocols to be incorporated by professionals.


Assuntos
Neoplasias Orofaríngeas , Revelação da Verdade , Humanos , Estudos Transversais , Odontólogos/psicologia , Autoavaliação (Psicologia) , Inquéritos e Questionários
4.
Med Oral Patol Oral Cir Bucal ; 27(2): e164-e173, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35218645

RESUMO

BACKGROUND: Appropriate DNA replication is vital to maintain cell integrity at the genomic level. Malfunction on DNA repair mechanisms can have implications related to tumor behavior. Our aim was to evaluate the expression of key complexes of the DNA mismatch-repair system MutSα (hMSH2-hMSH6) and MutSß (hMSH2-hMSH3) in a panel comprising the most common benign and malignant salivary gland tumors (SGT), and to determine their association with disease-free survival. MATERIAL AND METHODS: Ten cases of normal salivary gland (NSG) and 92 of SGT (54 benign and 38 malignant) were retrieved. Immunohistochemistry was performed for hMSH2, hMSH3, hMSH6. Scanned slides were digitally analyzed based on the percentage of positive cells with nuclear staining. Cases were further classified in MutSαhigh and MutSßhigh based on hMSH2-hMSH6 and hMSH3-hMSH6 expression, respectively. RESULTS: hMSH3 expression was lower in malignant SGT compared to NSG and benign cases. Adenoid cystic carcinoma (ACC) cases with perineural invasion presented a lower percentage of hMSH3 positive cells. hMSH6 was downregulated in both benign and malignant SGT compared to NSG. Malignant SGT cases with MutSαhigh expression had lower disease-free survival compared to MutSαlow cases. A 10.26-fold increased risk of presenting local recurrence was observed. CONCLUSIONS: Our findings suggest that a lack of hMSH3 protein function is associated with a more aggressive phenotype (malignancy and perineural invasion) and that MutSα overexpression predicts a poor clinical outcome in malignant SGT.


Assuntos
Reparo do DNA , Neoplasias das Glândulas Salivares , Intervalo Livre de Doença , Humanos , Imuno-Histoquímica , Proteína 2 Homóloga a MutS
6.
Osteoporos Int ; 32(12): 2449-2459, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34331067

RESUMO

Considering the lack of studies determining the real TPTD efficacy in individuals who develop MRONJ, our objective was to combine the available data on MRONJ cases treated with TPTD. The findings demonstrated that TPTD in combination with another therapy, especially antibiotic therapy, can be considered an effective protocol for MRONJ. PURPOSE: To integrate the data published on the effect of teriparatide (TPTD) therapy on cases of medication-related osteonecrosis of the jaws (MRONJ) into a comprehensive analysis of clinical features. METHODS: An electronic search was undertaken in six databases. Descriptive analyses of clinicodemographic data of MRONJ were carried out. Poisson regression was also run to evaluate predictors of total resolution of MRONJ treated with TPTD. RESULTS: Twenty-six publications comprising 111 cases were included. Most reported cases affected female individuals (82.0%) with a mean age of 76.54 years. Osteoporosis (76.5%) represented the main reason for using antiresorptive drugs, with bisphosphonates (98.1%) as the most frequently reported. Comorbidities were commonly present. The most related trigger factor of MRONJ was dental extraction (61.7%). Mandible (75.8%) was the most commonly affected site, with a mean evolution time of 5 months. MRONJ stage 2 (61.3%) was the most prevalent. Regarding TPTD treatment, in 45.1% cases, TPTD was used alone, with the total resolution being observed in 59.5% of the individuals. Associated therapy (54.9%) included surgery, antibiotic therapy, and laser therapy. Mean follow-up was 8.7 months. Poisson regression demonstrated that individuals with MRONJ stage 1 were 1.21 times more likely to present total resolution of osteonecrosis than individuals with MRONJ stage 3 (CI = 1.02-1.43; p < 0.023). Individuals who had undergone treatment with TPTD in association with another therapeutic modality were 1.21 times more likely to present total resolution of osteonecrosis than those who had undergone treatment with TPTD alone (CI = 1.40-1.39; p < 0.010). CONCLUSION: TPTD in combination with another therapy, especially antibiotic therapy, should be considered an effective therapeutic modality for MRONJ.


Assuntos
Osteonecrose da Arcada Osseodentária Associada a Difosfonatos , Conservadores da Densidade Óssea , Idoso , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/tratamento farmacológico , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/epidemiologia , Conservadores da Densidade Óssea/efeitos adversos , Difosfonatos , Feminino , Humanos , Arcada Osseodentária , Teriparatida/uso terapêutico
7.
Med Oral Patol Oral Cir Bucal ; 26(3): e393-e403, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33247564

RESUMO

BACKGROUND: Salivary gland cancers (SGC) represent an uncommon group of heterogeneous tumors. We performed a retrospective survey of SGC diagnosed in a reference center for treatment of malignant tumors from the south of Brazil aiming to determine the prognostic value of demographic, clinic and pathologic features. MATERIAL AND METHODS: Cases diagnosed as SGC between 2006 and 2016 were retrospectively collected. Medical records were examined to extract demographic, clinic, pathologic and follow-up information. RESULTS: One-hundred and seven cases of SGC were identified. The most common SGC were mucoepidermoid carcinoma (MEC) (n = 39) followed by adenoid cystic carcinoma (AdCC) (n = 29). Among AdCCs, 55.2% of cases were classified as cribriform, 27.6% as tubular and 17.2% as solid. The tubular subtype had the highest percentage of cases with perineural invasion (p=0.01). Among MEC, 61.5% of cases were classified as low grade, 15.4% as intermediate grade and 19.9% as high grade. Low grade MEC had the lowest percentage of cases with perineural invasion (p=0.04). The 5-year survival for loco-regional control, disease-free survival (DFS) and disease-specific survival were 75%, 70% and 84%, respectively. The following features were associated with poor DFS: advanced age (p=0.03), rural residency (p=0.01), being a smoker or former smoker (p=0.01), pain (p=0.03), nodal metastasis (p<0.001), need for chemotherapy (p=0.02), neck dissection (p=0.04), perineural invasion (p=0.01), and being diagnosed with AdCC compared to MEC (p=0.02). CONCLUSIONS: The clinco-demographic and pathologic features identified as prognostic factors reveal the profile of patients at increased risk of recurrence and who would benefit from closer follow-up.


Assuntos
Recidiva Local de Neoplasia , Neoplasias das Glândulas Salivares , Brasil/epidemiologia , Humanos , Prognóstico , Estudos Retrospectivos , Neoplasias das Glândulas Salivares/diagnóstico , Neoplasias das Glândulas Salivares/epidemiologia , Neoplasias das Glândulas Salivares/terapia
8.
Eur J Paediatr Dent ; 21(4): 292-298, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33337905

RESUMO

AIM: To evaluate the frequency and distribution of dental anomalies (DA) in a paediatric population. MATERIALS AND METHODS: Panoramic digital radiographs of children between 6 and 12 years old performed at a reference centre for radiographic exams were accessed. Two calibrated examiners evaluated the radiographs. The association between variables and outcomes was assessed using non-parametric tests. The significance level was set at 5%. RESULTS: Five hundred and twelve individuals were included and 61.3% presented at least one DA. The mean age of patients with DA (9.35±1.60) was significantly higher compared to patients with no anomalies (7.90±1.58). Patients with supernumerary tooth, however, were significantly younger. The most frequent DA were permanent tooth radicular dilacerations (38.1%), permanent tooth agenesis (29.3%), supernumerary tooth (6.4%) and impacted tooth (6.4%). Anterior teeth and female patients were more affected by radicular dilacerations. Dental agenesis was more frequent in the third molars followed by the upper lateral incisor. CONCLUSION: DA are quite frequent in the paediatric population and the most common DA observed herein could only be identified through imaging exams. The most appropriate timing to perform an investigation for the detection of dental anomalies appears to be between 9 and 10 years old.


Assuntos
Anodontia , Anormalidades Dentárias , Dente Supranumerário , Anodontia/diagnóstico por imagem , Anodontia/epidemiologia , Criança , Feminino , Humanos , Prevalência , Radiografia Panorâmica , Anormalidades Dentárias/diagnóstico por imagem , Anormalidades Dentárias/epidemiologia , Dente Supranumerário/diagnóstico por imagem , Dente Supranumerário/epidemiologia
10.
Med Oral Patol Oral Cir Bucal ; 25(3): e403-e409, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32040460

RESUMO

BACKGROUND: To analyze the trends of oral and oropharyngeal cancer mortality in Uruguay between 1997 and 2014 according to sex and age groups and its possible association with sociodemographic factors. MATERIAL AND METHODS: A time-series ecological study using secondary data was performed. The data about mortality due to oral and oropharyngeal cancers were obtained from the Statistics Vitals Department of the Public Health Ministry of Uruguay. To estimate the mortality trends of the historical series, by sex, anatomical site and age groups, linear regressions generated by the Prais-Winsten procedure were used. RESULTS: The analysis of mortality trends for oral cavity and oropharyngeal cancers in Uruguay indicated that the global mortality rate was stable over the studied period. The women's mortality rate increased from 0.51 per 100,000 in 1997 to 0.65 per 100,000 in 2014 while for men, rates per 100,000 went from 3.22 in 1997 to 2.20 per 100,000 in 2014. Mortality from oral cancer in men decreased between 1997 and 2014. Mortality by oropharyngeal cancer, irrespective of sex, remained stable. Analysis by cancer site revealed decreasing trends tumors situated in the base of the tongue and gum. Years of education, unemployment, smoking and Gini index were not associated with mortality trends. CONCLUSIONS: The overall mortality from oral and oropharyngeal cancer in Uruguay has remained constant in the period between 1997 and 2014. Oral cancer mortality decreased in men and increased in women and decreased at the base of the tongue. It's necessary to continue monitoring the behavior of these diseases.


Assuntos
Neoplasias Bucais , Neoplasias Orofaríngeas , Feminino , Humanos , Incidência , Masculino , Saúde Pública , Uruguai
11.
Oral Dis ; 24(6): 1012-1019, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29505701

RESUMO

OBJECTIVE: The diagnosis of oral lesions is often challenging for primary healthcare providers, which explains the high number of referrals to specialist care. This favors increases in waiting lines and delays in diagnosis, contributing to high mortality rates from oral cancer. This study aimed to summarize the experience of the EstomatoNet, a telediagnosis program catering to primary care dentists and physicians from southern Brazil. STUDY DESIGN: This exploratory study included all queries received by EstomatoNet from June 2015 to December 2016. Health providers (71 dentists and 18 physicians from primary care) submitted requests including clinical information and photographs of oral lesions by means of a cloud-based platform. Specialized oral medicine teleconsultants received the data, conveyed a diagnostic hypothesis, and conveyed management recommendations. RESULTS: Actinic cheilitis (n = 41, 15.8%), squamous cell carcinoma (n = 22, 8.5%), and inflammatory hyperplasia (21, 8.1%) were the most frequent diagnoses. Teleconsultants recommended referral to specialists in 42.9% of the cases, total biopsy in 23.6%, and follow-up in 16.2%. After the EstomatoNet use, the intention to refer the patients to face-to-face consultation reduced from 96.9% to 35.1%. CONCLUSION: Telediagnosis for oral lesions is feasible and has potential to improve the quality of primary health care by bridging the gap between primary and specialized health care.


Assuntos
Odontologia/métodos , Doenças da Boca/diagnóstico por imagem , Atenção Primária à Saúde/métodos , Telemedicina , Adulto , Idoso , Atitude do Pessoal de Saúde , Brasil , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fotografação , Encaminhamento e Consulta/estatística & dados numéricos , Adulto Jovem
12.
J Dent Res ; 95(2): 215-22, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26496800

RESUMO

Periodontitis is a chronic infectious disease driven by dysbiosis, an imbalance between commensal bacteria and the host organism. Periodontitis is a leading cause of tooth loss in adults and occurs in about 50% of the US population. In addition to the clinical challenges associated with treating periodontitis, the progression and chronic nature of this disease seriously affect human health. Emerging evidence suggests that periodontitis is associated with mechanisms beyond bacteria-induced protein and tissue degradation. Here, we hypothesize that bacteria are able to induce epigenetic modifications in oral epithelial cells mediated by histone modifications. In this study, we found that dysbiosis in vivo led to epigenetic modifications, including acetylation of histones and downregulation of DNA methyltransferase 1. In addition, in vitro exposure of oral epithelial cells to lipopolysaccharides resulted in histone modifications, activation of transcriptional coactivators, such as p300/CBP, and accumulation of nuclear factor-κB (NF-κB). Given that oral epithelial cells are the first line of defense for the periodontium against bacteria, we also evaluated whether activation of pathogen recognition receptors induced histone modifications. We found that activation of the Toll-like receptors 1, 2, and 4 and the nucleotide-binding oligomerization domain protein 1 induced histone acetylation in oral epithelial cells. Our findings corroborate the emerging concept that epigenetic modifications play a role in the development of periodontitis.


Assuntos
Epigênese Genética/genética , Histonas/genética , Periodontite/genética , Acetilação , Perda do Osso Alveolar/microbiologia , Animais , Linhagem Celular , DNA (Citosina-5-)-Metiltransferase 1 , DNA (Citosina-5-)-Metiltransferases/análise , Modelos Animais de Doenças , Disbiose/genética , Células Epiteliais/metabolismo , Células Epiteliais/microbiologia , Fusobacterium nucleatum/genética , Fusobacterium nucleatum/fisiologia , Retração Gengival/microbiologia , Interações Hospedeiro-Patógeno/genética , Humanos , Queratinócitos/metabolismo , Queratinócitos/microbiologia , Lipopolissacarídeos/farmacologia , Camundongos , Mucosa Bucal/citologia , Mucosa Bucal/microbiologia , NF-kappa B/análise , Proteína Adaptadora de Sinalização NOD1/análise , Perda da Inserção Periodontal/microbiologia , Periodontite/microbiologia , Modificação Traducional de Proteínas/genética , Receptor 1 Toll-Like/análise , Receptor 2 Toll-Like/análise , Receptor 4 Toll-Like/análise , Fatores de Transcrição de p300-CBP/análise
13.
Int J Sports Med ; 34(1): 87-2, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22791621

RESUMO

This study analyzed the effect of nandrolone decanoate (ND) on muscle repair and the expression of myogenic regulatory factors following cryoinjury in rat skeletal muscle. Adult male Wistar rats were randomly divided into 4 groups: control group, sham group, cryoinjured group treated with ND and non-injured group treated with ND. Treatment consisted of subcutaneous injections of ND (5 mg/kg) twice a week. After sacrifice, the tibialis anterior muscle was removed for the isolation of total RNA and analysis of myogenic regulatory factors using real-time PCR as well as morphological analysis using the hematoxylin-eosin assay. There was a significant increase in MyoD mRNA after 7 days and in myogenin mRNA after 21 days in the cryoinjured ND group in comparison to other groups in the same period. The morphological analysis revealed no edema or myonecrosis after 7 days as well as no edema or inflammatory infiltrate after 14 days in the cryoinjured ND group. In conclusion the anabolic steroid nandrolone decanoate can modulate the muscle repair process in rats following cryoinjury by influencing the expression of regulatory myogenic factors and phases of muscle repair.


Assuntos
Anabolizantes/farmacologia , Músculo Esquelético/efeitos dos fármacos , Nandrolona/análogos & derivados , Anabolizantes/administração & dosagem , Animais , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Injeções Subcutâneas , Masculino , Músculo Esquelético/lesões , Músculo Esquelético/patologia , Proteína MyoD/genética , Fatores de Regulação Miogênica/genética , Nandrolona/administração & dosagem , Nandrolona/farmacologia , Decanoato de Nandrolona , RNA/metabolismo , Distribuição Aleatória , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Tempo
14.
Indian J Dent Res ; 20(3): 365-9, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19884725

RESUMO

Inflammation of oral mucosa induced by anti neoplastic drugs is an important, dose limiting and costly side effect of cancer therapy. Here is presented an exacerbated case of oral mucositis associated with renal failure in a patient who underwent bone marrow transplantation. The clinical aspects and an integrated rehabilitation program are discussed below.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Mieloma Múltiplo/complicações , Insuficiência Renal/complicações , Estomatite/etiologia , Condicionamento Pré-Transplante/efeitos adversos , Transplante de Medula Óssea , Assistência Odontológica para Doentes Crônicos/métodos , Feminino , Humanos , Terapia a Laser , Pessoa de Meia-Idade , Mieloma Múltiplo/terapia , Estomatite/terapia , Resultado do Tratamento
15.
Oral Dis ; 13(3): 270-3, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17448207

RESUMO

AIM: The aim of the present study was to clinically evaluate the oral mucosa lesions of leprosy patients during and after multi-drug therapy. METHODS: Clinical examination, medical and dental history examination was performed in 100 leprosy patients. RESULTS: The results revealed that 71 patients, 50 men and 21 women, exibited oral lesions. The most frequent lesions were: fissured tongue (18 cases), inflammatory papillary hyperplasia (16 cases), chronic atrophic candidiasis (10 cases), fibroma (10 cases), erythematous candidiasis (eight cases), and traumatic ulceration (seven cases). CONCLUSION: We conclude that leprosy-related lesions are not present in patients undergoing treatment for leprosy, probably due to response to multidrug therapy.


Assuntos
Hanseníase/complicações , Doenças da Boca/etiologia , Idoso , Brasil , Estudos Transversais , Dermatoses Faciais/etiologia , Feminino , Humanos , Hansenostáticos/uso terapêutico , Hanseníase/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Mucosa Bucal/patologia
16.
Int Endod J ; 40(1): 72-8, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17209836

RESUMO

AIM: To present an additional case of intraosseous schwannoma involving the apical area in the mandibular alveolar bone mimicking an inflammatory periapical lesion. SUMMARY: This article describes a case of schwannoma periapically located mimicking an inflammatory periapical lesion in the mandible of a 34-year-old female. Diagnostic and therapeutic problems can occur when this lesion is misinterpreted as being endodontic in origin. The diagnosis, radiograph, immunohistochemical aspects and treatment are also discussed. KEY LEARNING POINTS: Intraosseous schwannoma is a rare unilocular radiolucency that when located periapically could be misdiagnosed as an endodontic lesion and result in unnecessary root canal treatment. The vitality of the pulp is an important test to exclude lesions of inflammatory origin. Histological examination is important to establish the diagnosis of lesions in the periradicular region.


Assuntos
Neoplasias Mandibulares/patologia , Neurilemoma/patologia , Granuloma Periapical/diagnóstico , Adulto , Diagnóstico Diferencial , Feminino , Humanos , Neoplasias Mandibulares/cirurgia , Neurilemoma/cirurgia
17.
J Nanosci Nanotechnol ; 7(10): 3421-30, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18330151

RESUMO

A classical protocol widely used in organic chemistry of aromatic and polyaromatic molecules has been successfully applied in this work for the decarboxylation of oxidized single-wall carbon nanotube (SWNT) to rend C-H SWNT derivatives. SWNT produced by arc discharge method have been oxidized during a purification process using strongly oxidant agents, such as hydrogen peroxide and nitric acid. The decarboxylation of oxidized SWNT has been conduced with copper(I) oxide in a 50:50 solution of N-methylpyrrolidone and quinoline. Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and acid-base potentiometric titration analyses were carried out to characterize quali and quantitatively the changes in the chemical environment on the SWNT surface in each step of the purification and the decarboxylation process. Those techniques showed the appearance of mainly carboxylic and phenolic groups after the purification process and the disappearance of the carboxylic groups after the decarboxylation reaction. Fourier transform infrared spectroscopy analysis indicated also the formation of aliphatic and aromatic C-H groups. X-ray photoelectron spectroscopy and potentiometric titration results determined an efficiency higher than 90% for our decarboxylation procedure. The purity and structural quality of the SWNT sample used in the decarboxylation process were evaluated by thermogravimetry and Raman spectroscopy. Thermogravimetric analysis identified a purified sample with approximately 80 wt% of SWNT, in fractions distributed in highly structured SWNTs (25 wt%), with distribution in composition, length and structural quality (35 wt%) and with very defective and short tubes (25 wt%). The damages on the purified SWNT walls were characterized by the Raman scattering analysis.


Assuntos
Cristalização/métodos , Nanotecnologia/métodos , Nanotubos de Carbono/química , Nanotubos de Carbono/ultraestrutura , Oxigênio/química , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Oxirredução , Tamanho da Partícula , Propriedades de Superfície
18.
Braz J Med Biol Res ; 39(4): 555-61, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16612480

RESUMO

The objective of the present study was to determine the frequency of somatic chromosomal anomalies and Y chromosomal microdeletions (azoospermia factor genes, AZF) in infertile males who seek assisted reproduction. These studies are very important because the assisted reproduction techniques (mainly intracytoplasmic sperm injection) bypass the natural selection process and some classical chromosomal abnormalities, microdeletions of AZF genes or some deleterious genic mutations could pass through generations. These genetic abnormalities can cause in the offspring of these patients male infertility, ambiguous external genitalia, mental retardation, and other birth defects. We studied 165 infertile men whose infertility was attributable to testicular problems (60 were azoospermic, 100 were oligospermic and 5 were asthenospermic). We studied 100 metaphases per patient with GTG banding obtained from temporary lymphocyte culture for chromosomal abnormality detection and performed a genomic DNA analysis using 28 Y chromosome-specific sequence-tagged sites for Y AZF microdeletion detection. Karyotyping revealed somatic anomalies in 16 subjects (16/165 = 9.6%). Of these 16, 12 were in the azoospermic group (12/60 = 20%) and 4 were in the oligospermic group (4/100 = 4%). The most common chromosomal anomaly was Klinefelter syndrome (10/165 = 6%). Microdeletions of AZF genes were detected in 12 subjects (12/160 = 7.5%). The frequencies detected are similar to those described previously. These results show the importance of genetic evaluation of infertile males prior to assisted reproduction. Such evaluation can lead to genetic counseling and, consequently, to primary and secondary prevention of mental retardation and birth defects.


Assuntos
Deleção Cromossômica , Cromossomos Humanos Y/genética , Deleção de Genes , Infertilidade Masculina/genética , Humanos , Cariotipagem , Masculino , Oligospermia/genética , Reação em Cadeia da Polimerase
19.
Braz. j. med. biol. res ; 39(4): 555-561, Apr. 2006. ilus, tab
Artigo em Inglês | LILACS | ID: lil-425077

RESUMO

The objective of the present study was to determine the frequency of somatic chromosomal anomalies and Y chromosomal microdeletions (azoospermia factor genes, AZF) in infertile males who seek assisted reproduction. These studies are very important because the assisted reproduction techniques (mainly intracytoplasmic sperm injection) bypass the natural selection process and some classical chromosomal abnormalities, microdeletions of AZF genes or some deleterious genic mutations could pass through generations. These genetic abnormalities can cause in the offspring of these patients male infertility, ambiguous external genitalia, mental retardation, and other birth defects. We studied 165 infertile men whose infertility was attributable to testicular problems (60 were azoospermic, 100 were oligospermic and 5 were asthenospermic). We studied 100 metaphases per patient with GTG banding obtained from temporary lymphocyte culture for chromosomal abnormality detection and performed a genomic DNA analysis using 28 Y chromosome-specific sequence-tagged sites for Y AZF microdeletion detection. Karyotyping revealed somatic anomalies in 16 subjects (16/165 = 9.6 percent). Of these 16, 12 were in the azoospermic group (12/60 = 20 percent) and 4 were in the oligospermic group (4/100 = 4 percent). The most common chromosomal anomaly was Klinefelter syndrome (10/165 = 6 percent). Microdeletions of AZF genes were detected in 12 subjects (12/160 = 7.5 percent). The frequencies detected are similar to those described previously. These results show the importance of genetic evaluation of infertile males prior to assisted reproduction. Such evaluation can lead to genetic counseling and, consequently, to primary and secondary prevention of mental retardation and birth defects.


Assuntos
Humanos , Masculino , Deleção Cromossômica , Cromossomos Humanos Y/genética , Deleção de Genes , Infertilidade Masculina/genética , Cariotipagem , Oligospermia/genética , Reação em Cadeia da Polimerase
20.
Int Endod J ; 36(6): 404-10, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12801287

RESUMO

AIM: To simultaneously analyse the expression of type I collagen, osteonectin and bone sialoprotein (BSP) in human dental pulp of different ages. METHODOLOGY: Cultured dental pulp fibroblasts (FP1 cell line), pulps from dental germs with incomplete root formation (n = 4) and pulps of erupted teeth with total root formation (n = 4) were used. Bone proteins were searched by immunohistochemistry and immunofluorescence using polyclonal antibodies and compared among the three groups assessed. RESULTS: Immunohistochemistry detected the three proteins in dental pulp tissue, as it labelled extracellular matrix, predentine and odontoblasts. The BSP label was weaker, when compared to both type I collagen and osteonectin. The presence of type I collagen was more evident in pulps from erupted teeth, when compared to germ dental pulps. On the other hand, a strong expression of osteonectin in germ dental pulps was observed. CONCLUSIONS: Regardless of the degree of maturation, dental pulps present type I collagen, osteonectin and BSP in the extracellular matrix (ECM) and in the odontoblastic layer. Thus, the results suggest that these proteins are related to the production and mineralization of dentine.


Assuntos
Colágeno Tipo I/análise , Polpa Dentária/citologia , Osteonectina/análise , Sialoglicoproteínas/análise , Linhagem Celular , Dentina/citologia , Matriz Extracelular/química , Fibroblastos/citologia , Técnica Direta de Fluorescência para Anticorpo , Humanos , Imuno-Histoquímica , Sialoproteína de Ligação à Integrina , Odontoblastos/citologia , Erupção Dentária , Germe de Dente/citologia , Dente não Erupcionado/patologia
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