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1.
PLoS One ; 15(8): e0235386, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32785221

RESUMO

Renewed excavations at the Neolithic site of Beisamoun (Upper Jordan Valley, Israel) has resulted in the discovery of the earliest occurrence of an intentional cremation in the Near East directly dated to 7031-6700 cal BC (Pre-Pottery Neolithic C, also known as Final PPNB, which spans ca. 7100-6400 cal BC). The funerary treatment involved in situ cremation within a pyre-pit of a young adult individual who previously survived from a flint projectile injury. In this study we have used a multidisciplinary approach that integrates archaeothanatology, spatial analysis, bioanthropology, zooarchaeology, soil micromorphological analysis, and phytolith identification in order to reconstruct the different stages and techniques involved in this ritual: cremation pit construction, selection of fuel, possible initial position of the corpse, potential associated items and funerary containers, fire management, post-cremation gesture and structure abandonment. The origins and development of cremation practices in the region are explored as well as their significance in terms of Northern-Southern Levantine connections during the transition between the 8th and 7th millennia BC.


Assuntos
Sepultamento/história , Cremação/história , História Antiga , Humanos
2.
Dent Clin North Am ; 60(4): 943-9, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27671963

RESUMO

With the growing complexity of health care, interprofessional communication and collaboration are essential to optimize the care of dental patients, including consideration of genetics. A dental case exemplifies the challenges and benefits of an interprofessional approach to managing pediatric patients with oligodontia and a family history of colon cancer. The interprofessional team includes dental, genetic, nutritional, and surgical experts.


Assuntos
Anodontia/genética , Neoplasias Colorretais/genética , Aconselhamento Genético , Comportamento de Busca de Informação , Relações Interprofissionais , Equipe de Assistência ao Paciente/organização & administração , Adolescente , Comunicação , Comportamento Cooperativo , Atenção à Saúde , Feminino , Humanos , MEDLINE , Educação de Pacientes como Assunto , Linhagem
4.
J Am Dent Assoc ; 146(3): 164-173.e4, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25726343

RESUMO

BACKGROUND: It has been proposed that the PST and PerioPredict genetic tests that are based on polymorphisms in interleukin 1 (IL-1) genes identify a subset of patients who experience fewer tooth extractions if provided with 2 annual preventive visits. Economic analyses indicate rationing preventive care to only "high-risk" genotypes, smokers, patients with diabetes, or combinations of these risk factors would reduce the cost of dental care by $4.8 billion annually in the United States. METHODS: Data presented in the study that claimed clinical utility for the PST and PerioPredict tests were obtained for reanalysis using logistic regression to assess whether the PST genetic test, smoking, diabetes, or number of preventive visits were risk factors for tooth extraction during a span of 16 years. Consistency of risk classification by the PST (version 1) and PerioPredict (version 2) genetic tests was evaluated in different ethnic groups from the 1000 Genomes database. RESULTS: Multivariate analyses revealed association of tooth extraction with diabetes (P < .0001), smoking (P < .0001), and number of preventive visits (P = .004), but no support for the PST genetic test (P = .96) nor indication that the benefit of 2 preventive visits was affected by this genetic test (P = .58). Classification of risk was highly inconsistent between the PST (version 1) and PerioPredict (version 2) genetic tests. CONCLUSIONS: Two annual preventive visits were supported as beneficial for all patients, and there was no evidence that the IL-1 PST genetic test has any effect on tooth extraction risk or influences the benefits of 2 annual preventive visits. PRACTICAL IMPLICATIONS: Neither IL-1 PST nor PerioPredict genetic tests are useful for rationing preventive dental care. Further research is needed to identify genetic biomarkers with robust clinical validity and clinical utility to effectively personalize the practice of dentistry.


Assuntos
Testes Genéticos , Interleucina-1/genética , Medicina Preventiva/métodos , Adulto , Assistência Odontológica/estatística & dados numéricos , Complicações do Diabetes/epidemiologia , Feminino , Marcadores Genéticos/genética , Predisposição Genética para Doença/genética , Testes Genéticos/métodos , Humanos , Cobertura do Seguro , Seguro Odontológico , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Fatores de Risco , Fumar/efeitos adversos , Doenças Dentárias/etiologia , Doenças Dentárias/genética
5.
J Am Dent Assoc ; 146(2): 79-86, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25637205

RESUMO

BACKGROUND: The caries lesion, the most commonly observed sign of dental caries disease, is the cumulative result of an imbalance in the dynamic demineralization and remineralization process that causes a net mineral loss over time. A classification system to categorize the location, site of origin, extent, and when possible, activity level of caries lesions consistently over time is necessary to determine which clinical treatments and therapeutic interventions are appropriate to control and treat these lesions. METHODS: In 2008, the American Dental Association (ADA) convened a group of experts to develop an easy-to-implement caries classification system. The ADA Council on Scientific Affairs subsequently compiled information from these discussions to create the ADA Caries Classification System (CCS) presented in this article. CONCLUSIONS: The ADA CCS offers clinicians the capability to capture the spectrum of caries disease presentations ranging from clinically unaffected (sound) tooth structure to noncavitated initial lesions to extensively cavitated advanced lesions. The ADA CCS supports a broad range of clinical management options necessary to treat both noncavitated and cavitated caries lesions. PRACTICAL IMPLICATIONS: The ADA CCS is available for implementation in clinical practice to evaluate its usability, reliability, and validity. Feedback from clinical practitioners and researchers will allow system improvement. Use of the ADA CCS will offer standardized data that can be used to improve the scientific rationale for the treatment of all stages of caries disease.


Assuntos
Cárie Dentária/classificação , Sociedades Odontológicas/normas , Cárie Dentária/patologia , Cárie Dentária/terapia , Humanos , Dente/patologia
6.
Clin J Am Soc Nephrol ; 9(3): 527-35, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24509297

RESUMO

BACKGROUND AND OBJECTIVES: The genetic cause of medullary cystic kidney disease type 1 was recently identified as a cytosine insertion in the variable number of tandem repeat region of MUC1 encoding mucoprotein-1 (MUC1), a protein that is present in skin, breast, and lung tissue, the gastrointestinal tract, and the distal tubules of the kidney. The purpose of this investigation was to analyze the clinical characteristics of families and individuals with this mutation. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Families with autosomal dominant interstitial kidney disease were referred for genetic analysis over a 14-year period. Families without UMOD or REN mutations prospectively underwent genotyping for the presence of the MUC1 mutation. Clinical characteristics were retrospectively evaluated in individuals with the MUC1 mutation and historically affected individuals (persons who were both related to genetically affected individuals in such a way that ensured that they could be genetically affected and had a history of CKD stage IV or kidney failure resulting in death, dialysis, or transplantation). RESULTS: Twenty-four families were identified with the MUC1 mutation. Of 186 family members undergoing MUC1 mutational analysis, the mutation was identified in 95 individuals, 91 individuals did not have the mutation, and111 individuals were identified as historically affected. Individuals with the MUC1 mutation suffered from chronic kidney failure with a widely variable age of onset of end stage kidney disease ranging from 16 to >80 years. Urinalyses revealed minimal protein and no blood. Ultrasounds of 35 individuals showed no medullary cysts. There were no clinical manifestations of the MUC1 mutation detected in the breasts, skin, respiratory system, or gastrointestinal tract. CONCLUSION: MUC1 mutation results in progressive chronic kidney failure with a bland urinary sediment. The age of onset of end stage kidney disease is highly variable, suggesting that gene-gene or gene-environment interactions contribute to phenotypic variability.


Assuntos
Mucina-1/genética , Mutação , Rim Policístico Autossômico Dominante/genética , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Análise Mutacional de DNA , Progressão da Doença , Feminino , Interação Gene-Ambiente , Predisposição Genética para Doença , Humanos , Rim/fisiopatologia , Falência Renal Crônica/genética , Falência Renal Crônica/fisiopatologia , Masculino , Pessoa de Meia-Idade , Linhagem , Fenótipo , Rim Policístico Autossômico Dominante/complicações , Rim Policístico Autossômico Dominante/diagnóstico , Rim Policístico Autossômico Dominante/fisiopatologia , Sistema de Registros , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Adulto Jovem
7.
J Periodontol ; 85(6): 810-8, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24171499

RESUMO

BACKGROUND: Although human gingival fibroblasts (hGFs) and human periodontal ligament fibroblasts (hPDLFs) exhibit numerous phenotypic similarities, it has been suggested that the secretory and behavioral differences, which exist between these cell types, are a result of the membrane protein composition of these cells. METHODS: Four matched pairs of hGFs and hPDLFs were cultured. Before confluence, membrane-bound and -associated proteins from cells of the fourth passage were extracted. The processed protein samples were evaluated using capillary-liquid chromatography-nanospray tandem mass spectrometry. Global protein identification was performed on an orbitrap mass spectrometer equipped with a microspray source operated in positive ion mode. Proteome software was used to validate protein identifications derived from tandem mass spectrometry sequencing results. RESULTS: Four hundred fifty proteins were common to both hGFs and hPDLFs. Of the proteins identified, 214 were known membrane-bound or -associated proteins, and 165 proteins were known nuclear-associated proteins. Twenty-seven proteins, identified from the 450 proteins, common to both hGFs and hPDLFs, were detected in statistically significant greater quantities in either hGFs or hPDLFs. More specifically, 13 proteins were detected in significantly greater quantities in hGFs, whereas 14 proteins were detected in significantly greater quantities in hPDLFs. CONCLUSIONS: Distinct differences in the cellular protein catalog may reflect the dynamic role and high energy requirements of hGFs in extracellular matrix remodeling and response to inflammatory challenge as well as the role of hPDLFs in monitoring mechanical stress and maintaining tissue homeostasis during regeneration and remineralization.


Assuntos
Fibroblastos/química , Gengiva/citologia , Ligamento Periodontal/citologia , Proteoma/análise , Adolescente , Adulto , Técnicas de Cultura de Células , Células Cultivadas , Cromatografia Líquida , Feminino , Gengiva/química , Humanos , Masculino , Proteínas de Membrana/análise , Proteínas Nucleares/análise , Ligamento Periodontal/química , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem , Adulto Jovem
8.
Case Rep Dent ; 2014: 605892, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25587461

RESUMO

Background. The orofaciodigital syndromes (OFDS) are a heterogeneous group of syndromes that affect the face, oral cavity, and the digits. OFDS type IV (OMIM %258860) is rare and characterized by broad nasal root and tip, orbital hypertelorism or telecanthus, micrognathia, hypoplastic mandible, and low-set ears. Oral symptoms may include cleft lip, cleft or highly arched palate, bifid uvula, cleft or hypoplastic maxillary and mandibular alveolar ridge, oral frenula, lingual hamartoma, and absent or hypoplastic epiglottis. Dental anomalies are common and generally include disturbances in the number of teeth. Case Report. This report presents a six-year-old girl, referred with the chief complaint of missing teeth. She was diagnosed as having OFDS type IV based on clinical findings. Her parents reported three deceased children and two fetuses that had the same phenotype. She was the seventh child of consanguineous parents who were first cousins. Conclusion. This is a very rare syndrome. Many reported OFDS type IV cases have consanguineous parents, consistent with an autosomal recessive trait. Manifestation of cleft palate in the healthy sibling may be mild expression of the disorder or an unrelated isolated cleft.

9.
J Dent Educ ; 77(6): 706-15, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23740907

RESUMO

The promotion and tenure process for faculty members varies, by design, for different disciplines, departments, and academic institutions. For many faculty members in U.S. dental schools, the process may thus appear nebulous and be difficult to navigate. In this article, we review the history, forces of change, and some of the mechanisms utilized for promotion and tenure of faculty in the health sciences, particularly for clinician-educators. Some institutions have successfully created hybrid tracks for clinician-educators in order to develop and recognize these faculty members' scholarly activity in addition to their clinical teaching. Hybrid tracks empower faculty members to successfully perform scholarly activities that realistically reflect institutional missions. The authors of this article conclude with a number of practical suggestions to enhance development and retention of faculty using the hybrid promotion and tenure mechanism. These include demonstrating the congruence of institutional mission, faculty activities, and promotion and tenure guidelines; developing scholarly activities for clinician-educators that can be measured in the promotion and tenure process; rewarding scholarly achievement for clinician-educators utilizing the promotion and tenure mechanism; and developing an evaluation system that accounts for changes in mission and faculty activities.


Assuntos
Mobilidade Ocupacional , Docentes de Odontologia , Faculdades de Odontologia/organização & administração , Desenvolvimento de Pessoal , Logro , Docentes de Odontologia/organização & administração , Humanos , Objetivos Organizacionais , Desenvolvimento de Pessoal/organização & administração , Ensino , Estados Unidos
10.
Periodontol 2000 ; 61(1): 266-78, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23240954

RESUMO

Genetic factors play an important etiologic role in destructive periodontal diseases. There have been reports that sex chromosomes, especially disorders associated with the X chromosome, affect periodontal health. Although numerous X-linked diseases have been reported to be associated with various periodontal diseases, the association of gingivitis and/or periodontitis with these genetic syndromes should be considered tenuous and raises the question of whether the periodontal manifestation truly arises from an underlying X-linked genetic etiology. A brief overview of genetics in relation to sex chromosomes and putative X-linked genetic periodontal diseases is given.


Assuntos
Doenças Genéticas Ligadas ao Cromossomo X/genética , Doenças Periodontais/genética , Periodontite Agressiva/genética , Genes Ligados ao Cromossomo X/genética , Genes Ligados ao Cromossomo Y/genética , Gengivite/genética , Humanos , Periodontite/genética
11.
PLoS One ; 7(10): e47628, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23144704

RESUMO

BACKGROUND: The mouth is a complex biological structure inhabited by diverse bacterial communities. The purpose of this study is to describe the effects of allogeneic stem cell transplantation on the oral microbiota and to examine differences among those patients who acquired respiratory complications after transplantation. METHODOLOGY/PRINCIPAL FINDINGS: All patients were consented at the National Institutes of Health, Clinical Center. Bacterial DNA was analyzed from patients' oral specimens using the Human Oral Microbe Identification Microarray. The specimens were collected from four oral sites in 45 allogeneic transplantation patients. Specimens were collected at baseline prior to transplantation, after transplantation at the nadir of the neutrophil count and after myeloid engraftment. If respiratory signs and symptoms developed, additional specimens were obtained. Patients were followed for 100 days post transplantation. Eleven patients' specimens were subjected to further statistical analysis. Many common bacterial genera, such as Streptococcus, Veillonella, Gemella, Granulicatella and Camplyobacter were identified as being present before and after transplantation. Five of 11 patients developed respiratory complications following transplantation and there was preliminary evidence that the oral microbiome changed in their oral specimens. Cluster analysis and principal component analysis revealed this change in the oral microbiota. CONCLUSIONS/SIGNIFICANCE: After allogeneic transplantation, the oral bacterial community's response to a new immune system was not apparent and many of the most common core oral taxa remained unaffected. However, the oral microbiome was affected in patients who developed respiratory signs and symptoms after transplantation. The association related to the change in the oral microbiota and respiratory complications after transplantation will be validated by future studies using high throughput molecular methods.


Assuntos
Bactérias/genética , Microbiota/genética , Boca/microbiologia , Transplante de Células-Tronco/métodos , Adulto , Bactérias/classificação , Análise por Conglomerados , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Análise de Componente Principal , RNA Ribossômico 16S/genética , Sistema Respiratório/microbiologia , Fatores de Tempo , Transplante Homólogo
12.
Int J Dent ; 2011: 196721, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22013442

RESUMO

The purpose of this study was to provide a univariate and multivariate analysis of genomic microbial data and salivary mass-spectrometry proteomic profiles for dental caries outcomes. In order to determine potential useful biomarkers for dental caries, a multivariate classification analysis was employed to build predictive models capable of classifying microbial and salivary sample profiles with generalization performance. We used high-throughput methodologies including multiplexed microbial arrays and SELDI-TOF-MS profiling to characterize the oral flora and salivary proteome in 204 children aged 1-8 years (n = 118 caries-free, n = 86 caries-active). The population received little dental care and was deemed at high risk for childhood caries. Findings of the study indicate that models incorporating both microbial and proteomic data are superior to models of only microbial or salivary data alone. Comparison of results for the combined and independent data suggests that the combination of proteomic and microbial sources is beneficial for the classification accuracy and that combined data lead to improved predictive models for caries-active and caries-free patients. The best predictive model had a 6% test error, >92% sensitivity, and >95% specificity. These findings suggest that further characterization of the oral microflora and the salivary proteome associated with health and caries may provide clinically useful biomarkers to better predict future caries experience.

15.
Dev Biol ; 344(2): 682-92, 2010 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-20510228

RESUMO

Tricho-dento-osseous (TDO) syndrome is an autosomal dominant disorder characterized by abnormalities in the thickness and density of bones and teeth. A 4-bp deletion mutation in the Distal-Less 3 (DLX3) gene is etiologic for most cases of TDO. To investigate the in vivo role of mutant DLX3 (MT-DLX3) on dentin development, we generated transgenic (TG) mice expressing MT-DLX3 driven by a mouse 2.3 Col1A1 promoter. Dentin defects were radiographically evident in all teeth and the size of the nonmineralized pulp was enlarged in TG mice, consistent with clinical characteristics in patients with TDO. High-resolution radiography, microcomputed tomography, and SEM revealed a reduced zone of mineralized dentin with anomalies in the number and organization of dentinal tubules in MT-DLX3 TG mice. Histological and immunohistochemical studies demonstrated that the decreased dentin was accompanied by altered odontoblast cytology that included disruption of odontoblast polarization and reduced numbers of odontoblasts. TUNEL assays indicated enhanced odontoblast apoptosis. Expression levels of the apoptotic marker caspase-3 were increased in odontoblasts in TG mice as well as in odontoblastic-like MDPC-23 cells transfected with MT-DLX3 cDNA. Expression of Runx2, Wnt 10A, and TBC1D19 colocalized with DLX3 expression in odontoblasts, and MT-DLX3 significantly reduced expression of all three genes. TBC1D19 functions in cell polarity and decreased TBC1D19 expression may contribute to the observed disruption of odontoblast polarity and apoptosis. These data indicate that MT-DLX3 acts to disrupt odontoblast cytodifferentiation leading to odontoblast apoptosis, and aberrations of dentin tubule formation and dentin matrix production, resulting in decreased dentin and taurodontism. In summary, this TG model demonstrates that MT-DLX3 has differential effects on matrix production and mineralization in dentin and bone and provides a novel tool for the investigation of odontoblast biology.


Assuntos
Dentina/metabolismo , Odontoblastos/metabolismo , Deleção de Sequência/genética , Animais , Osso e Ossos/metabolismo , Caspase 3/análise , Caspase 3/genética , Caspase 3/metabolismo , Displasia Ectodérmica/genética , Displasia Ectodérmica/metabolismo , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Odontoblastos/química , Odontogênese/genética , Dente/metabolismo
16.
J Dent Child (Chic) ; 77(1): 36-41, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20359428

RESUMO

PURPOSE: Papilion-Lefèvre syndrome (PLS) is a rare autosomal recessive disorder that involves palmoplantar keratosis (PK) and severe aggressive periodontitis. Cathepsin C (CTSC) gene mutations are etiologic for PLS, with more than 60 different mutations reported in different ethnic groups worldwide. The purpose of this study was to report a novel cathepsin C mutation in a Brazilian patient. METHODS: A 4-year-old boy presented with aggressive periodontitis, recession, missing teeth, and hyperkeratosis of the palms of hands and soles. Peripheral blood samples were obtained from family members for genomic DNA isolation. The coding region and exon/intron boundaries of the CTSC gene were amplified and sequenced. RESULTS: The patient had a PLS phenotype, which included PK and early-onset severe periodontitis. Sequence analysis showed a novel CTSC mutation (c.267-268del) present in the homozygous state. CONCLUSION: This report described a novel mutation in a family with Brazilian Papillon-Lefèvre syndrome and presented a review of all cathepsin C (65) mutations reported to date.


Assuntos
Catepsina C/genética , Doença de Papillon-Lefevre/genética , Brasil , Pré-Escolar , Consanguinidade , Humanos , Masculino , Mutação , Doença de Papillon-Lefevre/enzimologia , Linhagem , Fenótipo
17.
Am J Hum Genet ; 85(2): 204-13, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19664745

RESUMO

Through linkage analysis and candidate gene sequencing, we identified three unrelated families with the autosomal-dominant inheritance of early onset anemia, hypouricosuric hyperuricemia, progressive kidney failure, and mutations resulting either in the deletion (p.Leu16del) or the amino acid exchange (p.Leu16Arg) of a single leucine residue in the signal sequence of renin. Both mutations decrease signal sequence hydrophobicity and are predicted by bioinformatic analyses to damage targeting and cotranslational translocation of preprorenin into the endoplasmic reticulum (ER). Transfection and in vitro studies confirmed that both mutations affect ER translocation and processing of nascent preprorenin, resulting either in reduced (p.Leu16del) or abolished (p.Leu16Arg) prorenin and renin biosynthesis and secretion. Expression of renin and other components of the renin-angiotensin system was decreased accordingly in kidney biopsy specimens from affected individuals. Cells stably expressing the p.Leu16del protein showed activated ER stress, unfolded protein response, and reduced growth rate. It is likely that expression of the mutant proteins has a dominant toxic effect gradually reducing the viability of renin-expressing cells. This alters the intrarenal renin-angiotensin system and the juxtaglomerular apparatus functionality and leads to nephron dropout and progressive kidney failure. Our findings provide insight into the functionality of renin-angiotensin system and stress the importance of renin analysis in families and individuals with early onset hyperuricemia, anemia, and progressive kidney failure.


Assuntos
Anemia/genética , Genes Dominantes , Hiperuricemia/genética , Falência Renal Crônica/genética , Renina/genética , Adolescente , Adulto , Idade de Início , Anemia/metabolismo , Linhagem Celular , Criança , Pré-Escolar , Simulação por Computador , Feminino , Ligação Genética , Humanos , Hiperuricemia/metabolismo , Rim/citologia , Rim/ultraestrutura , Falência Renal Crônica/metabolismo , Masculino , Pessoa de Meia-Idade , Mutação , Linhagem , Renina/metabolismo , Análise de Sequência de DNA , Adulto Jovem
18.
Am J Med Genet A ; 149A(7): 1392-8, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19530186

RESUMO

Amelogenesis imperfectas (AI) are a group of inherited defects of dental enamel formation that show both clinical and genetic heterogeneity. Seven Turkish families segregating autosomal recessive AI (ARAI) were evaluated for evidence of a genetic etiology of AI for the seven major candidate gene loci (AMBN, AMELX, ENAM, FAM83H, KLK4, MMP20, and TUFT1). Dental and periodontal characteristics of the affected members of these families were also described. The mean scores of DMFS and dfs indices were 9.7 and 9.6, respectively. The mean PPD was 2.2 mm and the percentage of the sites with plaque and BOP were 87.8% and 72.4%, respectively. The exons and intron/exon junctions of the candidate genes were sequenced and no gene mutations were identified in any individuals. These findings support the existence of an additional gene(s) that are etiologic for ARAI in these families.


Assuntos
Amelogênese Imperfeita/genética , Genes Recessivos , Adolescente , Amelogenina/genética , Criança , Pré-Escolar , Análise Mutacional de DNA , Proteínas do Esmalte Dentário/genética , Família , Feminino , Genes Recessivos/fisiologia , Predisposição Genética para Doença , Humanos , Calicreínas/genética , Masculino , Metaloproteinase 20 da Matriz/genética , Turquia
19.
Eur J Hum Genet ; 17(6): 774-84, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19092777

RESUMO

Human linkage and association studies suggest a gene(s) for nonsyndromic cleft lip with or without cleft palate (CL/P) on chromosome 4q31-q32 at or near the platelet-derived growth factor-C (PDGF-C) locus. The mouse Pdgfc(-/-) knockout shows that PDGF-C is essential for palatogenesis. To evaluate the role of PDGF-C in human clefting, we performed sequence analysis and SNP genotyping using 1048 multiplex CL/P families and 1000 case-control samples from multiple geographic origins. No coding region mutations were identified, but a novel -986 C>T SNP (rs28999109) was significantly associated with CL/P (P=0.01) in cases from Chinese families yielding evidence of linkage to 4q31-q32. Significant or near-significant association was also seen for this and several other PDGF-C SNPs in families from the United States, Spain, India, Turkey, China, and Colombia, whereas no association was seen in families from the Philippines, and Guatemala, and case-controls from Brazil. The -986T allele abolished six overlapping potential transcription regulatory motifs. Transfection assays of PDGF-C promoter reporter constructs show that the -986T allele is associated with a significant decrease (up to 80%) of PDGF-C gene promoter activity. This functional polymorphism acting on a susceptible genetic background may represent a component of human CL/P etiology.


Assuntos
Fenda Labial/genética , Fissura Palatina/genética , Linfocinas/genética , Fator de Crescimento Derivado de Plaquetas/genética , Polimorfismo de Nucleotídeo Único/genética , Regiões Promotoras Genéticas/genética , Transcrição Gênica/genética , Alelos , Estudos de Casos e Controles , Predisposição Genética para Doença , Humanos
20.
Cells Tissues Organs ; 189(1-4): 224-9, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-18714142

RESUMO

Amelogenesis imperfecta (AI) is caused by AMEL, ENAM, MMP20 and KLK4 gene mutations. Mice lacking expression of the AmelX, Enam and Mmp20 genes have been generated. These mouse models provide tools for understanding enamel formation and AI pathogenesis. This study describes the AI phenotypes and relates them to their mouse model counterparts. Human AI phenotypes were determined in a clinical population of AI families and published cases. Human and murine teeth were evaluated using light and electron microscopy. A total of 463 individuals from 54 families were evaluated and mutations in the AMEL, ENAM and KLK4 genes were identified. The majority of human mutations for genes coding enamel nonproteinase proteins (AMEL and ENAM) resulted in variable hypoplasia ranging from local pitting to a marked, generalized enamel thinning. Specific AMEL mutations were associated with abnormal mineralization and maturation defects. Amel and Enam null murine models displayed marked enamel hypoplasia and a complete loss of prism structure. Human mutations in genes coding for the enamel proteinases (MMP20 and KLK4) cause variable degrees of hypomineralization. The murine Mmp20 null mouse exhibits both hypoplastic and hypomineralized defects. The currently available Amel and Enam mouse models for AI exhibit enamel phenotypes (hypoplastic) that are generally similar to those seen in humans. Mmp20 null mice have a greater degree of hypoplasia than humans with MMP20 mutations. Mice lacking expression of the currently known genes associated with the human AI conditions provide useful models for understanding the pathogenesis of these conditions.


Assuntos
Amelogenina/genética , Proteínas do Esmalte Dentário/genética , Esmalte Dentário/enzimologia , Esmalte Dentário/patologia , Calicreínas/genética , Metaloproteinase 20 da Matriz/genética , Mutação/genética , Animais , Esmalte Dentário/ultraestrutura , Dentição , Humanos , Camundongos , Fenótipo , Pigmentação
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