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1.
Head Neck ; 40(5): E53-E57, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29473257

RESUMO

BACKGROUND: Primary intestinal-type adenocarcinoma of the tongue is rare. This represents the first reported case of a primary mixed adenoneuroendocrine carcinoma (MANEC) of the tongue arising within a congenital enteric cyst. METHODS: A 52-year-old man presented with a midline tongue mass that was connected to the mucosal surface with an epithelial-lined sinus tract. Morphological examination and immunohistochemical profiling of the neoplasm were performed. RESULTS: Histopathological evaluation showed a primary MANEC arising within a preexisting congenital enteric cyst, comprising both adenocarcinoma and neuroendocrine components. The adenocarcinoma had a colonic-type morphology and coexpressed CK7, CK20, and CDX2. Imaging and colonoscopy excluded a distant primary colorectal neoplasm. CONCLUSION: The association of primary MANEC of the tongue with a gastrointestinal heterotopic cyst supports an origin from entrapped endodermal elements as opposed to salivary duct origin. This case raises the awareness of a rare yet prognostically important complication of a gastrointestinal heterotopic cyst.


Assuntos
Adenocarcinoma/complicações , Adenocarcinoma/patologia , Cistos/congênito , Cistos/complicações , Neoplasias da Língua/complicações , Neoplasias da Língua/patologia , Cistos/patologia , Humanos , Masculino , Pessoa de Meia-Idade
2.
Head Neck Pathol ; 10(4): 437-443, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27161103

RESUMO

Fourteen cases with 18 grossly expansive lesions diagnosed over a period of 15 years as either "familial gigantiform cementoma" or "osseous dysplasia with jaw expansion" in an African population sample were reviewed. Eight lesions occurred in the anterior mandible, the maxilla was affected by four, three patients presented with more than one lesion and the most common associated pathologies were tooth displacement, conventional non expanding florid osseous dysplasia and simple bone cyst. No history of similar lesions in relatives of the diseased were recorded. The radiolucent fibrous component contained globular bone deposits and cellular osteoid with trabecular differentiation which matured into radiodense mineralized masses. Resorption of the cellular bone created cavities which are proposed to represent the early stage of simple bone cyst formation. It is recommended that "expansive osseous dysplasia" replace the out-dated term "familial gigantiform cementoma". The differential diagnoses of expansive osseous dysplasias are discussed.


Assuntos
Cementoma/patologia , Displasia Fibrosa Óssea/patologia , Neoplasias Maxilomandibulares/patologia , Osteomielite/patologia , Adolescente , Adulto , Idoso , População Negra , Criança , Feminino , Humanos , Doenças Maxilomandibulares/patologia , Masculino , Pessoa de Meia-Idade
3.
Head Neck Pathol ; 10(3): 332-5, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26920555

RESUMO

The unique chequered pattern of elephant ivory has made it a desired commodity for the production of various works of art. The demand however outstrips the supply and with soaring prices, illegal tusk harvesting is thriving on the African continent. Formal restrictions placed on trade in elephant products have been ineffective in reversing the rapid decline in elephant numbers. We are presently facing the reality of extinction of free roaming elephant on the African continent. This paper describes the histogenesis of the chequered pattern, the genomic impact of ivory harvesting on the phenotype of breeding herds, and the contribution of science to tracing the origin of illegal ivory.


Assuntos
Elefantes/genética , Dente , Animais , Fenótipo , Dente/química
4.
Artigo em Inglês | MEDLINE | ID: mdl-25547821

RESUMO

Chronic kidney disease is an increasing public health problem, with a worldwide prevalence estimated to be between 8% and 16%. The metabolic alterations induce bone and soft tissue changes, and the encompassing term chronic kidney disease-mineral and bone disorder syndrome (CKD-MBD) is used to describe them. The cardinal manifestations of the syndrome are bone catabolism and soft tissue calcifications, which ultimately compromise the cardiovascular and skeletal systems. In rare cases, tumorous enlargement of the craniofacial bones occurs. This article provides a brief review of the pathogenesis and imaging of craniofacial changes in CKD-MBD and reports on two cases of expansive jaw lesions. The term expansive renal osteitis fibrosa is recommended to describe these lesions.


Assuntos
Doenças Ósseas Metabólicas/etiologia , Distúrbio Mineral e Ósseo na Doença Renal Crônica/etiologia , Doenças Maxilomandibulares/etiologia , Insuficiência Renal Crônica/complicações , Adulto , Biópsia , Doenças Ósseas Metabólicas/diagnóstico , Doenças Ósseas Metabólicas/patologia , Distúrbio Mineral e Ósseo na Doença Renal Crônica/diagnóstico , Distúrbio Mineral e Ósseo na Doença Renal Crônica/patologia , Diagnóstico Diferencial , Evolução Fatal , Feminino , Humanos , Doenças Maxilomandibulares/diagnóstico , Doenças Maxilomandibulares/patologia
5.
J Oral Pathol Med ; 44(4): 239-43, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24646006

RESUMO

Chronic kidney disease-mineral bone disorder (CKD-MBD) is a syndrome encompassing skeletal and extra skeletal changes associated with chronic kidney disease. It progresses silently until an advanced clinical stage when complications impact on the quality of life and survival rates of patients. The maxillofacial manifestations are unique and may play an important role in the early identification of changes which could influence the management of these patients. The goal of this review is to highlight the maxillofacial features, pathology, and principles of management of CKD-MBD.


Assuntos
Doenças Ósseas Metabólicas/metabolismo , Doenças Ósseas Metabólicas/patologia , Insuficiência Renal Crônica/metabolismo , Insuficiência Renal Crônica/patologia , Ossos Faciais/metabolismo , Ossos Faciais/patologia , Humanos , Minerais/metabolismo , Qualidade de Vida
6.
Head Neck Pathol ; 8(4): 475-81, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25409845

RESUMO

Metabolic bone diseases often are asymptomatic and progress sub clinically. Many patients present at a late stage with catastrophic skeletal and extra skeletal complications. In this article, we provide an overview of normal bone remodeling and a synopsis of recent developments in the following conditions: osteoporosis, rickets/osteomalacia, endocrine-induced bone disease, chronic kidney disease-mineral bone disorder and Paget's disease of bone. Our discussion will emphasize the clinical and microscopic manifestations of these diseases in the jaws.


Assuntos
Doenças Ósseas Metabólicas/patologia , Doenças Maxilomandibulares/patologia , Humanos
7.
J Oral Maxillofac Pathol ; 18(Suppl 1): S90-5, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25364188

RESUMO

A small percentage of patients treated for Hodgkin's disease are at risk of developing a second malignancy. The appearance of secondary malignancies such as leukemia, carcinoma or non-Hodgkin's lymphomas may be attributed to the mutagenic effects of chemotherapy and/or radiotherapy. Most secondary non-Hodgkin's lymphomas are of the B-cell type, but isolated cases were reportedly of a T-cell lineage. A review of the literature pertaining to the development of secondary peripheral T-cell lymphomas is presented along with the description of an additional case. The latter developed in the tonsil and was diagnosed as a Lennert's lymphoma (lymphoepithelioid T cell lymphoma)on histological and immunological grounds. This report also reviews the development of a of peripheral T-cell lymphoma described in patients following chemotherapy and/or radiotherapy for Hodgkin's disease.

8.
Artigo em Inglês | MEDLINE | ID: mdl-22862981

RESUMO

Classification systems and associated terminology are inherently slow in reflecting rapidly unfolding scientific discoveries in the mechanism and presentation of diseases. Misleading concepts, which often have historical value only, may become entrenched in the literature, leading to confusion and inaccurate communication. The purpose of this communication is to stimulate discussion and debate on inappropriate terminology associated with fibro-osseous disease that continues to be perpetuated in the literature. Use of the terms "cementum," "aggressive," "active," "gigantiform," and "maturation" are questioned, and the criteria applied to the interpretation of secondary changes in fibro-osseous lesions critically are evaluated.


Assuntos
Cementoma/classificação , Terminologia como Assunto , Cementoma/patologia , Cemento Dentário/patologia , Fibroma Ossificante/classificação , Células Gigantes/patologia , Humanos , Cistos Maxilomandibulares/classificação , Cistos Maxilomandibulares/patologia , Tumores Odontogênicos/classificação
9.
Proc Biol Sci ; 279(1737): 2433-41, 2012 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-22337695

RESUMO

Longitudinal studies have revealed how variation in resource use within consumer populations can impact their dynamics and functional significance in communities. Here, we investigate multi-decadal diet variations within individuals of a keystone megaherbivore species, the African elephant (Loxodonta africana), using serial stable isotope analysis of tusks from the Kruger National Park, South Africa. These records, representing the longest continuous diet histories documented for any extant species, reveal extensive seasonal and annual variations in isotopic--and hence dietary--niches of individuals, but little variation between them. Lack of niche distinction across individuals contrasts several recent studies, which found relatively high levels of individual niche specialization in various taxa. Our result is consistent with theory that individual mammal herbivores are nutritionally constrained to maintain broad diet niches. Individual diet specialization would also be a costly strategy for large-bodied taxa foraging over wide areas in spatio-temporally heterogeneous environments. High levels of within-individual diet variability occurred within and across seasons, and persisted despite an overall increase in inferred C(4) grass consumption through the twentieth century. We suggest that switching between C(3) browsing and C(4) grazing over extended time scales facilitates elephant survival through environmental change, and could even allow recovery of overused resources.


Assuntos
Adaptação Biológica/fisiologia , Isótopos de Carbono/análise , Dieta , Elefantes , Isótopos de Nitrogênio/análise , Isótopos de Oxigênio/análise , Dente/química , Determinação da Idade pelos Dentes/métodos , Determinação da Idade pelos Dentes/veterinária , Animais , Dentina/química , Modelos Lineares , Espectrometria de Massas , África do Sul , Dente/anatomia & histologia
10.
J Maxillofac Oral Surg ; 11(1): 101-4, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23449257

RESUMO

Two cases of peripheral odontogenic myxoma with a verifiable location in gingival soft tissue and without bone involvement were compared with those reported in the literature. This study showed that they form a distinct albeit rare clinical entity with a potential to grow into large disfiguring lesions. The probability that small peripheral odontogenic myxomas are interpreted as edematous irritation fibromas may contribute to the small number of peripheral odontogenic myxomas recorded in the literature. The differential diagnosis of soft tissue myxoid proliferations is discussed.

11.
Artigo em Inglês | MEDLINE | ID: mdl-21237426

RESUMO

OBJECTIVES: The aim of this study was to report on the clinicopathologic features of osseous dysplasias (ODs) that manifest with gross expansion in a black South African hospital population sample. STUDY DESIGN: The files of 9 histology-verified expansive ODs in 8 patients were reviewed. The clinical records and radiographs were analyzed and compared with reports in the literature. RESULTS: The main complaint of all patients was related to expansion of the jaw. All except 1 were female, with ages between 26 and 71 years and sizes of the lesions ranging from 4 to 15 cm. No history of similar lesions in family members was obtained. All lesions occurred in the mandible and 6 crossed the midline. The expansive growth pattern was associated with persistence of radiolucent areas in the lesions which microscopically consisted of cellular fibro-osseous tissue. Resorption of mineralized deposits by osteoclasts was prominent in the radiolucent parts of the lesion. Maturation with enlargement of the radiodense component was associated with a decrease in osteoclast activity and the formation of lobular bone masses and confluent psammomatous mineralized deposits. CONCLUSION: We propose the term "expansive osseous dysplasia" for the rare albeit important clinical subcategory of ODs that manifest with progressive jaw expansion. Suspension of osteoclast activity plays an important role in the maturation of the lesions into dense mineralized masses.


Assuntos
Displasia Fibrosa Óssea/patologia , Doenças Mandibulares/patologia , Adulto , Idoso , Feminino , Displasia Fibrosa Óssea/classificação , Displasia Fibrosa Óssea/diagnóstico por imagem , Displasia Fibrosa Óssea/cirurgia , Humanos , Masculino , Doenças Mandibulares/classificação , Doenças Mandibulares/diagnóstico por imagem , Doenças Mandibulares/cirurgia , Pessoa de Meia-Idade , Radiografia , Estudos Retrospectivos , África do Sul
12.
J Maxillofac Oral Surg ; 10(4): 334-9, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23204750

RESUMO

This is a case report of a patient presenting with a destructive lesion with histologic features of a low grade malignancy in a predominantly myxoid matrix. Various low grade myxoid malignancies were considered in the differential diagnosis of which an overview is presented. A literature review of the ultrastructural findings and possible histogenesis is discussed along with the diagnostic criteria and recent change in the terminology regarding the malignancies previously diagnosed as myxoid malignant fibrous histiocytomas. A final diagnosis of a myxofibrosarcoma was only possible after assessing the immuno-histochemical profile, results of histochemical stains and ultrastructural features of this lesion.

13.
J Oral Pathol Med ; 39(5): 435-9, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20537055

RESUMO

BACKGROUND: It is diagnostically difficult to differentiate plasmablastic lymphomas (PBLs) from plasma cell neoplasms with plasmablastic differentiation. Plasmablastic lymphomas are currently classified as 'PBL of the oral mucosa' and 'PBL with plasmacytic differentiation'. METHODS: Forty-five cases of PBL were retrieved from the Departments of Oral Pathology of the Universities of Pretoria and Limpopo, South Africa. Clinical features and HIV status were recorded and each case was classified as 'PBL of the oral mucosa type' or as 'PBL with plasmacytic differentiation'. Immunohistochemistry included: CD45, CD3, CD20, CD79a, CD38, CD138, MUM1, Ki-67 and kappa and lambda light chains. Positivity was recorded based on the percentage of positive staining cells as focal (5-20%); intermediate (20-70%) or diffuse (>70%). In situ hybridization was performed for Epstein-Barr virus (EBV) and HHV-8. Results were recorded as positive or negative. RESULTS: All cases showed some degree of plasmacytic differentiation. All were negative for CD20 with reactive T cells detected with CD3. Diffuse and strong positive staining was found with Ki-67 and MUM1, but variable immunoreactivity was found with CD79a, CD45, CD38 and CD138. Twenty cases (47%) showed light chain restriction. Epstein-Barr virus was detected in 44/45 cases and HHV-8 in none. CONCLUSIONS: The morphological classification of PBLs is not valid as all cases showed some degree of plasmacytic differentiation. We propose that PBLs with light chain restriction be reclassified as 'plasmablastic extramedullary plasmacytomas' and managed accordingly. The rest represents true PBLs. The true nature of these neoplasms as an entity should be further investigated with molecular and genetic studies.


Assuntos
Linfoma Relacionado a AIDS/classificação , Linfoma Imunoblástico de Células Grandes/classificação , Mucosa Bucal/patologia , Neoplasias Bucais/classificação , Plasmocitoma/classificação , Adulto , Diferenciação Celular , Feminino , Soropositividade para HIV/complicações , Herpesvirus Humano 4/isolamento & purificação , Humanos , Cadeias Leves de Imunoglobulina/análise , Imuno-Histoquímica , Hibridização In Situ , Linfoma Relacionado a AIDS/imunologia , Linfoma Relacionado a AIDS/patologia , Linfoma Relacionado a AIDS/virologia , Linfoma Imunoblástico de Células Grandes/imunologia , Linfoma Imunoblástico de Células Grandes/patologia , Linfoma Imunoblástico de Células Grandes/virologia , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/imunologia , Neoplasias Bucais/patologia , Neoplasias Bucais/virologia , Plasmocitoma/imunologia , Plasmocitoma/patologia , Plasmocitoma/virologia , RNA Viral/análise , Estudos Retrospectivos , África do Sul
14.
Head Face Med ; 5: 22, 2009 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-19895712

RESUMO

Fibrous dysplasia has been regarded as a developmental skeletal disorder characterized by replacement of normal bone with benign cellular fibrous connective tissue. It has now become evident that fibrous dysplasia is a genetic disease caused by somatic activating mutation of the Gsalpha subunit of G protein-coupled receptor resulting in upregulation of cAMP. This leads to defects in differentiation of osteoblasts with subsequent production of abnormal bone in an abundant fibrous stroma. In addition there is an increased production of IL-6 by mutated stromal fibrous dysplastic cells that induce osteoclastic bone resorption.


Assuntos
Displasia Fibrosa Óssea , Diferenciação Celular , Displasia Fibrosa Óssea/diagnóstico por imagem , Displasia Fibrosa Óssea/etiologia , Displasia Fibrosa Óssea/genética , Displasia Fibrosa Óssea/patologia , Humanos , Mutação , Osteoblastos/patologia , Radiografia
15.
Artigo em Inglês | MEDLINE | ID: mdl-19748290

RESUMO

OBJECTIVES: The objectives of this study were to describe the internal macroscopic architecture of resected specimens of ameloblastoma and to correlate the findings with radiographs and microscopic features. STUDY DESIGN: Resection specimens of 24 ameloblastomas were retrieved from the files of the Department of Oral Pathology at the University of Limpopo. The neoplasms were sectioned in parallel slices and the macroscopic features recorded and each slice was radiographed and sampled for microscopic examination. The macroscopic features were correlated with respective microscopic and radiological appearances. RESULTS: Twenty-three ameloblastomas affected the mandible and 1 the maxilla and measured between 3.3 and 20 cm in greatest diameter. Six cases were unicystic, 2 of which showed incomplete septae both of which presented multilocular on radiographs. Intracystic proliferations were present in 15 cases. These proliferations showed macroscopic features of either small or large nodules with or without the formation of confluent plaques, focal papillary lesions, or multinodular masses that protruded into the cystic cavities. Microscopically these proliferations were characterized by foci of inflammation or plexiform or solid epithelial proliferations, one of which showed a focus of carcinoma in situ, adenomatoid differentiation and another osteodentin deposits. Seven cases had foci of stromal desmoplastic change, one of which exhibited mineralized deposits resembling bone. CONCLUSIONS: The assessment of the cystic nature of ameloblastomas on 2-dimensional radiographs is inaccurate. Intraluminal proliferations, in situ carcinomatous change, adenoid differentiation, stromal osteodentin, and bone deposits and desmoplasia were found to be focal rather than generalized phenomena in resection specimen of ameloblastoma.


Assuntos
Ameloblastoma/patologia , Neoplasias Mandibulares/patologia , Adolescente , Adulto , Idoso , Ameloblastoma/diagnóstico por imagem , Feminino , Humanos , Masculino , Neoplasias Mandibulares/diagnóstico por imagem , Radiografia , Adulto Jovem
16.
Head Face Med ; 5: 4, 2009 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-19152712

RESUMO

Myeloma is characterized by monoclonal bone marrow plasmacytosis, the presence of M-protein in serum and/or in urine and osteolytic bone lesions. HIV-seropositive subjects with myeloma are younger at the time of diagnosis of the tumour and usually the myeloma has a more aggressive clinical course than it does in HIV-seronegative subjects. A case of an HIV-seropositive woman in whom myeloma was diagnosed following progressive swelling of the face, is reported. In addition to bone marrow plasmacytosis and the presence of M-protein in the serum, the patient had an extramedullary lesion affecting the oral cavity, maxilla, parotid gland and paranasal sinuses, and extending intracranially and intraorbitally.


Assuntos
Neoplasias Faciais/complicações , Soropositividade para HIV/complicações , Mieloma Múltiplo/complicações , Neoplasias Faciais/diagnóstico , Feminino , Humanos , Pessoa de Meia-Idade , Mieloma Múltiplo/diagnóstico
17.
SADJ ; 63(3): 158-61, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18689348

RESUMO

T cell non-Hodgkin lymphoma is characterized by uncontrolled cellular proliferation of immature malignant clones. HIV-associated T cell non-Hodgkin lymphoma comprises a heterogeneous group of lymphoproliferative neoplastic entities classified according to morphological, immunological, genetic and clinical features. Extranodal T cell non-Hodgkin lymphoma of the oral cavity is uncommon. A case is presented with extranodal T cell non-Hodgkin lymphoma as an initial sign of HIV-infection. The characteristics of HIV-associated non-Hodgkin lymphoma are discussed.


Assuntos
Linfoma Relacionado a AIDS/diagnóstico , Linfoma de Células T/diagnóstico , Neoplasias Bucais/diagnóstico , Adulto , Diagnóstico Diferencial , Feminino , Humanos
18.
Cases J ; 1(1): 13, 2008 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-18577259

RESUMO

INTRODUCTION: Congenital oral granular cell tumour of the newborn is an uncommon benign tumour of uncertain origin. The typical clinical appearance is of a single nodule occurring on the anterior maxillary ridge. In 10% of cases there are multiple lesions. The occurrence of congenital epulis in non-Caucasians is rare. CASE PRESENTATION: Two firm pedunculated nodular lesions were noticed in the mouth of a 3-day-old black female: one on the anterior maxillary ridge and the other further posteriorly in the midline of the palate. Both lesions were excised when the baby was nine days old. Microscopic examination of the lesions showed densely packed round to oval cells with abundant granular eosinophilic cytoplasm and uniform nuclei. The diagnosis was congenital granular cell tumour. CONCLUSION: Congenital oral granular cell tumour occurs almost exclusively in Caucasian newborns but also rarely in black infants. The parents should be assured of the benign nature and the simple treatment of the condition.

20.
J Periodontol ; 79(2): 362-8, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18251652

RESUMO

BACKGROUND: Kaposi sarcoma (KS) is the most common human immunodeficiency virus (HIV)-associated neoplasm (HIV-KS). Highly active antiretroviral therapy (HAART) results in a decrease in the incidence and prevalence of HIV-KS as well as in clinical improvement. However, in a subset of subjects who are HIV seropositive, KS may recrudesce early following the introduction of HAART as an immune reconstitution inflammatory syndrome (IRIS). METHODS: The management of a patient who is HIV seropositive with rapid clinical worsening of oral KS lesions shortly after the initiation of HAART was documented. Repeated serologic testing for CD4(+) T-cell count and microscopic examination of two biopsy specimens of the oral lesion, one taken before and the other taken after cytotoxic chemotherapy, followed by surgical excision was the treatment modality used. RESULTS: Microscopic examination of the incisional biopsy specimen taken from the oral lesion at the time of the initial consultation confirmed the clinical diagnosis of KS. The sequential serological tests showed a progressive increase in CD4(+) T-cell counts that paralleled the rapid clinical worsening of the KS disease. This was consistent with the diagnosis of IRIS-associated HIV-KS. Subsequent cytotoxic chemotherapy brought about resolution of the IRIS and regression of the HIV-KS lesions. Microscopic examination of a biopsy specimen obtained after cytotoxic chemotherapy did not show any of the original KS. The residual palatal exophytic mass was excised. CONCLUSIONS: IRIS-associated HIV-KS is not a disease, but rather a temporary paradoxical immunoinflammatory reaction brought about by improvement in immune status following HAART. IRIS-associated HIV-KS can be controlled effectively by limited systemic cytotoxic chemotherapy in the setting of HAART.


Assuntos
Infecções por HIV/complicações , Síndrome Inflamatória da Reconstituição Imune/etiologia , Neoplasias Palatinas/etiologia , Sarcoma de Kaposi/etiologia , Adulto , Antineoplásicos/uso terapêutico , Terapia Antirretroviral de Alta Atividade/efeitos adversos , Feminino , Infecções por HIV/tratamento farmacológico , Humanos , Síndrome Inflamatória da Reconstituição Imune/tratamento farmacológico , Contagem de Leucócitos , Neoplasias Palatinas/tratamento farmacológico , Neoplasias Palatinas/cirurgia , Sarcoma de Kaposi/tratamento farmacológico , Sarcoma de Kaposi/cirurgia
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