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1.
Am J Transplant ; 17(4): 944-956, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27801552

RESUMO

T helper 17 (Th17)-dependent autoimmune responses can develop after heart or lung transplantation and are associated with fibro-obliterative forms of chronic rejection; however, the specific self-antigens involved are typically different from those associated with autoimmune disease. To investigate the basis of these responses, we investigated whether removal of regulatory T cells or blockade of function reveals a similar autoantigen bias. We found that Th17 cells specific for collagen type V (Col V), kα1-tubulin, and vimentin were present in healthy adult peripheral blood mononuclear cells, cord blood, and fetal thymus. Using synthetic peptides and recombinant fragments of the Col V triple helical region (α1[V]), we compared Th17 cells from healthy donors with Th17 cells from Col V-reactive heart and lung patients. Although the latter responded well to α1(V) fragments and peptides in an HLA-DR-restricted fashion, Th17 cells from healthy persons responded in an HLA-DR-restricted fashion to fragments but not to peptides. Col V, kα1-tubulin, and vimentin are preferred targets of a highly conserved, hitherto unknown, preexisting Th17 response that is MHC class II restricted. These data suggest that autoimmunity after heart and lung transplantation may result from dysregulation of an intrinsic mechanism controlling airway and vascular homeostasis.


Assuntos
Autoantígenos/imunologia , Colágeno Tipo V/imunologia , Imunidade Celular/imunologia , Linfócitos T Reguladores/imunologia , Células Th17/imunologia , Tubulina (Proteína)/imunologia , Vimentina/imunologia , Adolescente , Adulto , Criança , Feminino , Humanos , Leucócitos Mononucleares , Masculino , Pessoa de Meia-Idade , Adulto Jovem
2.
Oral Dis ; 22 Suppl 1: 120-7, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27109280

RESUMO

Well into the fourth decade of the HIV/AIDS pandemic, we can look back on the early years, the initial discoveries, and the broad sweep of the progress of our understanding of the nature, causes, and significance of the oral lesions seen in those infected with the virus. Prominent among these is oral hairy leukoplakia (HL), a previously unknown lesion of the mouth associated with Epstein-Barr virus (EBV) and initially seen only in people with AIDS, in the then-recognized risk groups, or those shown to be HIV positive. Subsequently, it became clear that the distribution of HL extends well beyond the HIV spectrum. In this brief review, we consider the clinical and histological features of HL, discuss how it was discovered, explore its cause, diagnosis, relationship with AIDS, pathogenesis, significance in EBV biology, options for management, and how it changes with HIV/AIDS therapy.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/imunologia , Infecções Oportunistas Relacionadas com a AIDS/patologia , Herpesvirus Humano 4 , Leucoplasia Pilosa/imunologia , Leucoplasia Pilosa/patologia , Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Infecções Oportunistas Relacionadas com a AIDS/virologia , Humanos , Hospedeiro Imunocomprometido , Leucoplasia Pilosa/diagnóstico , Leucoplasia Pilosa/virologia
3.
Am J Transplant ; 14(7): 1512-22, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24866539

RESUMO

IL17-dependent autoimmunity to collagen type V (Col V) has been associated with lung transplant obliterative bronchiolitis. Unlike the T helper 1 (Th1)-dependent immune responses to Tetanus Toxoid (TT), the Th17 response to Col V in lung transplant patients and its Th1/17 variant observed in coronary artery disease patients requires IL-1ß, tumor necrosis factor α and CD14(+) cells. Given the involvement of the P2X7 receptor (P2X7R) in monocyte IL-1ß responses, we investigated its role in Th17-, Th1/17- and Th1-mediated proinflammatory responses. Transfer of antigen-pulsed peripheral blood mononucleated cells (PBMCs) from Col V-reactive patients into SCID mouse footpads along with P2X7R antagonists revealed a selective inhibition of Col V-, but not TT-specific swelling responses. P2X7R inhibitors blocked IL-1ß induction from monocytes, including both Col V-α1 peptide-induced (T-dependent), as well as native Col V-induced (T-independent) responses. Significantly higher P2X7R expression was found on CXCR3(neg) CCR4(+)/6(+) CD4(+) [Th17] versus CXCR3(+)CCR4/6(neg) CD4(+) [Th1] subsets in PBMCs, suggesting that the paradigm of selective dependence on P2X7R might extend beyond Col V autoimmunity. Indeed, P2X7R inhibitors suppressed not only anti-Col V, but also Th1/17-mediated alloimmunity, in a heart transplant patient without affecting anti-viral Epstein-Barr virus responses. These results suggest that agents targeting the P2X7R might effectively treat Th17-related transplant pathologies, while maintaining Th1-immunity to infection.


Assuntos
Transplante de Coração , Imunidade Celular/imunologia , Interleucina-17/imunologia , Transplante de Pulmão , Monócitos/imunologia , Receptores Purinérgicos P2X7/metabolismo , Células Th1/imunologia , Animais , Antineoplásicos/farmacologia , Autoimunidade/imunologia , Colágeno Tipo V/imunologia , Colágeno Tipo V/metabolismo , Citometria de Fluxo , Rejeição de Enxerto/imunologia , Humanos , Hipersensibilidade Tardia , Técnicas Imunoenzimáticas , Interferon gama , Interleucina-17/metabolismo , Camundongos , Camundongos SCID , Monócitos/metabolismo , Monócitos/patologia , Receptores Purinérgicos P2X7/química , Receptores Purinérgicos P2X7/imunologia , Suramina/farmacologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Linfócitos T/patologia , Células Th1/metabolismo , Células Th1/patologia
4.
Nat Genet ; 13(3): 361-5, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8673139

RESUMO

Ehlers-Danlos syndrome (EDS) is a genetically and pathogenetically heterogeneous group of disorders of which at least 11 types have been described. All are connective tissue disorders characterized by defects of the skin, ligaments and blood vessels with the clinical spectrum ranging from innocuous findings to lethality. Mutations in the genes encoding the major fibrillar collagen types I and III have been demonstrated in EDS types VII and IV, respectively, while mutations in the lysyl hydroxylase and ATP7A genes, with roles in collagen cross-linking, are responsible for EDS types VI and IX. The biochemical and molecular bases for the most common forms of EDS (types I, II and III) are unknown. Here, we describe a balanced translocation between chromosome 9 and an X chromosome that disrupts the minor fibrillar collagen type V gene COL5A1 in a patient with both EDS type I and hypomelanosis of Ito. The breakpoint occurs at 9q34 within COL5A1 intron 24 and interestingly, within a LINE-1 (L1) element at Xp21.1. A fusion mRNA between COL5A1 and an Alu sequence is produced, but no aberrant protein is detectable. Rather, the amount of type V collagen is reduced in the patient's fibroblasts, suggesting haploinsufficiency as a cuase of the phenotype. This demonstrates that a mutation in a type V collagen gene, COL5A1, results in EDS type I, and shows the involvement of L1 sequences in a constitutional chromosomal translocation. Because collagen type V is a heteromorphic protein in which molecules may be composed of polypeptides encoded by three COL5A genes, this suggests all three genes as candidates for mutations in EDS.


Assuntos
Colágeno/genética , Síndrome de Ehlers-Danlos/genética , Transtornos da Pigmentação/genética , Translocação Genética , Sequência de Bases , Northern Blotting , Criança , Cromossomos Humanos Par 9 , Síndrome de Ehlers-Danlos/complicações , Eletroforese em Gel de Poliacrilamida , Humanos , Dados de Sequência Molecular , Mutação , Transtornos da Pigmentação/complicações , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Cromossomo X
5.
Nat Genet ; 4(1): 62-6, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-8513326

RESUMO

Recessive dystrophic epidermolysis bullosa is a severe mutilating genodermatosis. Previous ultrastructural demonstrations of altered anchoring fibrils, and recent genetic linkage analyses have suggested that type VII collagen, the major component of anchoring fibrils, is a candidate gene. We have identified a homozygous methionine-to-lysine mutation in two affected siblings, while their unaffected mother and half-brother are heterozygous carriers. The mutation resides in a highly conserved region of the C-terminus of type VII collagen, strongly suggesting that it is the cause of the disease in this family.


Assuntos
Colágeno/genética , Epidermólise Bolhosa Distrófica/genética , Mutação , Sequência de Aminoácidos , Animais , Sequência de Bases , Criança , Consanguinidade , Cricetinae , Análise Mutacional de DNA , Feminino , Genes Recessivos , Homozigoto , Humanos , Masculino , Camundongos , Dados de Sequência Molecular , Linhagem , Filogenia , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Especificidade da Espécie
6.
J Clin Dent ; 22(3): 62-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21905399

RESUMO

OBJECTIVE: The aim of this study was to characterize, in vitro, the mode of action of calcium sodium phosphosilicate (NovaMin) in occluding dentin tubules for the purpose of treating dentin hypersensitivity. METHODS: Calcium sodium phosphosilicate (CSPS) was combined with artificial saliva on surfaces of prepared dentin discs. The layer formed was initially examined by a scanning electron microscope (SEM). Focused ion beam (FIB) milling was used to make bulk cross-sections and thin film lamellae. Low kV scanning transmission electron microscopy (STEM), energy dispersive x-ray spectroscopy (EDS), and selected area electron diffraction were then used to characterize, chemically and structurally, the layer formed and the material occluding the tubules. Experiments were also performed to assess the suitability of using an environmental scanning electron microscope (ESEM) in wet mode to follow the transition from CSPS to hydroxyapatite. RESULTS: SEM imaging showed that a layer was formed on the treated dentin samples, and that this layer occluded tubules. Chemical and structural analysis of this material showed that it was hydroxyapatite-like. The wet mode ESEM experiments demonstrated that this technique has the potential to follow the transition from CSPS to the crystalline hydroxyapatite material. CONCLUSION: The use of modern imaging and analysis techniques has demonstrated, in vitro, the reaction of CSPS from an amorphous material to a crystalline hydroxyapatite-like material. These experiments confirmed an occlusion mode of action for CSPS for the treatment of dentin hypersensitivity.


Assuntos
Dessensibilizantes Dentinários/farmacologia , Sensibilidade da Dentina/tratamento farmacológico , Dentina/efeitos dos fármacos , Vidro , Condicionamento Ácido do Dente/métodos , Fosfatos de Cálcio/química , Fosfatos de Cálcio/farmacologia , Ácido Cítrico/química , Cristalografia , Dentina/química , Dentina/ultraestrutura , Dessensibilizantes Dentinários/química , Durapatita/química , Vidro/química , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão e Varredura , Tamanho da Partícula , Saliva Artificial/química , Silicatos/química , Silicatos/farmacologia , Espectrometria por Raios X , Fatores de Tempo
7.
J Clin Dent ; 22(3): 68-73, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21905400

RESUMO

OBJECTIVE: To characterize in vitro the formation and robustness of a layer formed on dentin following treatment with a fluoridated toothpaste containing calcium sodium phosphosilicate (NovaMin) using modem imaging and analysis techniques. METHODS: Calcium sodium phosphosilicate (CSPS)-containing toothpaste was brushed on to etched dentin specimens twice daily for up to five days. In between applications the samples were stored in artificial saliva. Additionally, certain samples underwent a chemical challenge in the form of a dietary acid, whereby samples were exposed to a cola or grapefruit juice beverage for five minutes on day 4 of the five-day study. The ability of the CSPS-containing formulation to occlude tubules was assessed visually by scanning electron microscope (SEM) imaging and compared to a water control. In a second experiment, the mechanical resistance of the layer was assessed using profilometry after controlled brushing for 200 brush strokes with a wet medium-bristled toothbrush. To visualize the layer and characterize the tubule occlusion, longitudinal cross-sections were prepared using a focused ion beam scanning electron microscope (FIB SEM), and analysis performed by energy dispersive x-ray spectroscopy (EDS) and electron diffraction. Owing to the complexity of the mixed material deposited after application of the toothpaste, material from inside a dentin tubule was selectively removed after five days of treatment, and the morphologically different materials imaged and analyzed by electron diffraction in the transmission electron microscope (TEM). RESULTS: SEM inspection showed significant coverage of the dentin samples after application of CSPS toothpaste for all five days, in contrast to the water control where the majority of tubules remained open after all five days. Exposure of the NovaMin-treated samples to common dietary acids did not lead to re-exposure of the tubules. Profilometry measurements demonstrated an intact layer covering the dentin surface after one and five days. EDS analysis and electron diffraction indicated the layer and the material plugging the tubule to be a calcium phosphate material with a crystallographic structure similar to hydroxyapatite. CONCLUSION: CSPS contained in toothpaste formulations adhered to exposed dentin surfaces. The layer formed was resistant to acid and mechanical challenges. Characterization of this layer indicated it was hydroxyapatite-like in nature.


Assuntos
Cariostáticos/farmacologia , Dessensibilizantes Dentinários/farmacologia , Dentina/efeitos dos fármacos , Fluoretos/farmacologia , Vidro , Cremes Dentais/farmacologia , Condicionamento Ácido do Dente/métodos , Bebidas , Fosfatos de Cálcio/química , Fosfatos de Cálcio/farmacologia , Bebidas Gaseificadas , Cariostáticos/química , Fenômenos Químicos , Citrus paradisi , Cristalografia , Dentina/ultraestrutura , Dessensibilizantes Dentinários/química , Durapatita/química , Fluoretos/química , Vidro/química , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Saliva Artificial/química , Silicatos/química , Silicatos/farmacologia , Espectrometria por Raios X , Fatores de Tempo , Escovação Dentária/instrumentação , Escovação Dentária/métodos , Cremes Dentais/química , Água/química
8.
Science ; 271(5247): 360-2, 1996 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-8553073

RESUMO

Bone morphogenetic proteins (BMPs) are bone-derived factors capable of inducing ectopic bone formation. Unlike other BMPs, BMP-1 is not like transforming growth factor-beta (TGF-beta), but it is the prototype of a family of putative proteases implicated in pattern formation during development in diverse organisms. Although some members of this group, such as Drosophila tolloid (TLD), are postulated to activate TGF-beta-like proteins, actual substrates are unknown. Procollagen C-proteinase (PCP) cleaves the COOH-propeptides of procollagens I, II, and III to yield the major fibrous components of vertebrate extracellular matrix. Here it is shown that BMP-1 and PCP are identical. This demonstration of enzymatic activity for a BMP-1/TLD-like protein links an enzyme involved in matrix deposition to genes involved in pattern formation.


Assuntos
Metaloendopeptidases/metabolismo , Proteínas/metabolismo , Sequência de Aminoácidos , Animais , Proteína Morfogenética Óssea 1 , Proteínas Morfogenéticas Ósseas , Humanos , Metaloendopeptidases/química , Camundongos , Dados de Sequência Molecular , Peso Molecular , Fragmentos de Peptídeos/metabolismo , Pró-Colágeno/metabolismo , Proteínas/química , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo
9.
J Oral Pathol Med ; 38(6): 481-8, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19594839

RESUMO

The Oral HIV/AIDS Research Alliance (OHARA) is part of the AIDS Clinical Trials Group (ACTG), the largest HIV clinical trials organization in the world. Its main objective is to investigate oral complications associated with HIV/AIDS as the epidemic is evolving, in particular, the effects of antiretrovirals on oral mucosal lesion development and associated fungal and viral pathogens. The OHARA infrastructure comprises: the Epidemiologic Research Unit (at the University of California San Francisco), the Medical Mycology Unit (at Case Western Reserve University) and the Virology/Specimen Banking Unit (at the University of North Carolina). The team includes dentists, physicians, virologists, mycologists, immunologists, epidemiologists and statisticians. Observational studies and clinical trials are being implemented at ACTG-affiliated sites in the US and resource-poor countries. Many studies have shared end-points, which include oral diseases known to be associated with HIV/AIDS measured by trained and calibrated ACTG study nurses. In preparation for future protocols, we have updated existing diagnostic criteria of the oral manifestations of HIV published in 1992 and 1993. The proposed case definitions are designed to be used in large-scale epidemiologic studies and clinical trials, in both US and resource-poor settings, where diagnoses may be made by non-dental healthcare providers. The objective of this article is to present updated case definitions for HIV-related oral diseases that will be used to measure standardized clinical end-points in OHARA studies, and that can be used by any investigator outside of OHARA/ACTG conducting clinical research that pertains to these end-points.


Assuntos
Síndrome da Imunodeficiência Adquirida/diagnóstico , Infecções por HIV/diagnóstico , Doenças da Boca/diagnóstico , Infecções Oportunistas Relacionadas com a AIDS/diagnóstico , Infecções Oportunistas Relacionadas com a AIDS/microbiologia , Infecções Oportunistas Relacionadas com a AIDS/virologia , Antirretrovirais/uso terapêutico , Candidíase Bucal/diagnóstico , Carcinoma de Células Escamosas/diagnóstico , Queilite/microbiologia , Ensaios Clínicos como Assunto , Países em Desenvolvimento , Estudos Epidemiológicos , Gengivite Ulcerativa Necrosante/diagnóstico , Herpes Labial/diagnóstico , Humanos , Leucoplasia Pilosa/virologia , Linfoma Relacionado a AIDS/diagnóstico , Linfoma não Hodgkin/diagnóstico , Doenças da Boca/microbiologia , Doenças da Boca/virologia , Neoplasias Bucais/diagnóstico , Úlceras Orais/diagnóstico , Doenças Parotídeas/classificação , Doenças Parotídeas/diagnóstico , Sarcoma de Kaposi/diagnóstico , Estomatite Aftosa/diagnóstico , Estomatite Herpética/diagnóstico , Terminologia como Assunto , Estados Unidos , Verrugas/virologia
10.
Oral Dis ; 15(1): 52-60, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19017280

RESUMO

OBJECTIVE: To determine the impact of highly active antiretroviral therapy (HAART) on salivary gland function in human immunodeficiency virus (HIV) positive women from the Women's Interagency HIV Study (WIHS). DESIGN: Longitudinal cohort study. SUBJECTS AND METHODS: A total of 668 HIV positive women from the WIHS cohort with an initial and at least one follow-up oral sub-study visit contributed 5358 visits. Salivary gland function was assessed based on a dry mouth questionnaire, whole unstimulated and stimulated salivary flow rates, salivary gland enlargement or tenderness and lack of saliva on palpation of the major salivary glands. MAIN OUTCOME MEASURES: Changes in unstimulated and stimulated flow rates at any given visit from that of the immediate prior visit (continuous variables). The development of self-reported dry mouth (present/absent), enlargement or tenderness of salivary glands (present/absent), and absence of secretion on palpation of the salivary glands were binary outcomes (yes/no). RESULTS: Protease Inhibitor (PI) based HAART was a significant risk factor for developing decreased unstimulated (P = 0.01) and stimulated (P = 0.0004) salivary flow rates as well as salivary gland enlargement (P = 0.006) as compared with non-PI based HAART. CONCLUSIONS: PI-based HAART therapy is a significant risk factor for developing reduced salivary flow rates and salivary gland enlargement in HIV positive patients.


Assuntos
Terapia Antirretroviral de Alta Atividade , Soropositividade para HIV/tratamento farmacológico , Glândulas Salivares/efeitos dos fármacos , Adolescente , Adulto , Idoso , Fármacos Anti-HIV/efeitos adversos , Fármacos Anti-HIV/uso terapêutico , Terapia Antirretroviral de Alta Atividade/efeitos adversos , Contagem de Linfócito CD4 , Estudos de Coortes , Feminino , Seguimentos , HIV/genética , Inibidores da Protease de HIV/efeitos adversos , Inibidores da Protease de HIV/uso terapêutico , Transcriptase Reversa do HIV/antagonistas & inibidores , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , RNA Viral/análise , Inibidores da Transcriptase Reversa/efeitos adversos , Inibidores da Transcriptase Reversa/uso terapêutico , Fatores de Risco , Saliva/efeitos dos fármacos , Saliva/metabolismo , Taxa Secretória/efeitos dos fármacos , Sialadenite/induzido quimicamente , Xerostomia/induzido quimicamente , Adulto Jovem
11.
Clin Oral Implants Res ; 19(12): 1233-45, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19040438

RESUMO

BACKGROUND: This study used a rat tibial marrow ablation model to test the hypothesis that bone remodeling within the medullary canal varies with bone graft materials of different chemical compositions and structural properties, impacting marrow cavity restoration. Bone graft materials were selected based on their relative resorption or degradation in vivo and their osteogenic properties. METHODS: Following ablation of the right tibial marrow in male Sabra-strain rats, materials were implanted in the proximal marrow cavity: poly-D,L-lactide-co-glycolide 75 : 25 (PLGA); coralline-hydroxyapatite (HA), calcium-sulfate (CaSO4), collagen-HA-tricalcium phosphate granules, anorganic bovine bone mineral, demineralized bone matrix (DBM), 45S5 Bioglass (BG), PLGA with BG 50 : 50, PLGA : BG 80 : 20, and PLGA and PLGA:BG 50 : 50 plus bone marrow (BM). Control tibias were ablated but received no implants. At 2 (endosteal bone healing), 4 (marrow cavity remodeling) and 8 weeks (marrow restoration), six to eight animals per group were euthanized and tibias processed for histomorphometry of proximal and distal medullary canals. RESULTS: Control tibias showed primary bone in proximal and distal medullary canals at 2 weeks, with trabeculae surrounded by cellular marrow. At 4 and 8 weeks, control trabeculae were thinned and marrow had more fat cells. In the treated tibias, trabecular bone volume (TBV) varied with time and was material specific. Most implants supported comparable TBV at 2 weeks. Sites with CaSO4 or DBM exhibited decreased TBV with time whereas trabecular bone was retained in proximal tibias containing other materials, closely juxtaposed to the implants. TBV did not always correlate directly with implant volume, but changes in BM volume were correlated inversely with TBV. Addition of BM increased marrow restoration in sites containing PLGA; however, BM reduced restoration of marrow when added to PLGA : BG. Although the presence of implants in the proximal tibia resulted in retention of trabecular bone, there was a time-dependent reduction in TBV in distal canals; the rate and extent of the distal TBV reduction were implant dependent. CONCLUSIONS: Thus, although many materials can support bone formation in the marrow cavity, bone quality, quantity, and physical relationship to the implant, and its rate of resorption differ in a material-dependent manner, resulting in differences in the restoration of marrow. CLINICAL RELEVANCE: Bone graft materials should be selected not only for their ability to support new bone formation but also for their impact on the remodeling phase of bone healing.


Assuntos
Medula Óssea/efeitos dos fármacos , Matriz Óssea/efeitos dos fármacos , Remodelação Óssea/efeitos dos fármacos , Substitutos Ósseos/farmacologia , Regeneração/efeitos dos fármacos , Animais , Medula Óssea/fisiologia , Remodelação Óssea/fisiologia , Fosfatos de Cálcio/farmacologia , Sulfato de Cálcio/farmacologia , Cerâmica/farmacologia , Colágeno/farmacologia , Combinação de Medicamentos , Hidroxiapatitas/farmacologia , Ácido Láctico/farmacologia , Masculino , Minerais/farmacologia , Osseointegração/efeitos dos fármacos , Osseointegração/fisiologia , Ácido Poliglicólico/farmacologia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Próteses e Implantes , Distribuição Aleatória , Ratos , Regeneração/fisiologia , Tíbia
12.
J Clin Invest ; 95(3): 1328-34, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7883979

RESUMO

Epidermolysis bullosa (EB) is a group of heritable mechano-bullous skin diseases classified into three major categories on the basis of the level of tissue separation within the dermal-epidermal basement membrane zone. In the most severe, dystrophic (scarring) forms of EB, blisters form below the cutaneous basement membrane at the level of the anchoring fibrils, which are composed of type VII collagen. Ultrastructural observations of altered anchoring fibrils and genetic linkage to the type VII collagen locus (COL7A1) have implicated COL7A1 as the candidate gene in the dystrophic forms of EB. We have recently cloned the entire cDNA and the gene for human COL7A1. In this study, we describe distinct mutations in both COL7A1 alleles in three brothers with severe, mutilating recessive dystrophic EB (the Hallopeau-Siemens type, HS-RDEB). The patients are compound heterozygotes for two different mutations, both of which result in a premature termination codon in COL7A1, and the parents were shown to be clinically heterozygous carries of the respective mutations. Premature termination codons in both alleles of COL7A1 appear to be the underlying cause of severe, recessive dystrophic EB in this family.


Assuntos
Códon de Terminação/genética , Colágeno/genética , Epidermólise Bolhosa Distrófica/genética , Genes Recessivos/genética , Adolescente , Adulto , Alelos , Sequência de Bases , Epidermólise Bolhosa Distrófica/patologia , Éxons/genética , Feminino , Humanos , Japão/etnologia , Masculino , Dados de Sequência Molecular , Mutação , Núcleo Familiar , Ácidos Nucleicos Heteroduplexes/genética , Linhagem , Reação em Cadeia da Polimerase
13.
Mol Cell Biol ; 5(8): 1894-900, 1985 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3018535

RESUMO

The herpes simplex virus type 1 thymidine kinase (tk) gene lacks introns and produces stable mRNA in the absence of splicing. We have prepared a hybrid gene by placing the first exon, first intron (first intervening sequence, designated IVS1), and most of the second exon of the normal human beta-globin gene into the 3' untranslated region of the tk gene. Although this hybrid gene contains all globin sequences presumed necessary for the splicing of IVS1, predominantly, unspliced stable cytoplasmic RNA is produced in both long- and short-term expression assays. Moreover, stable unspliced cytoplasmic RNA is detected whether the intron is situated in a sense or an antisense orientation. Efficient splicing of IVS1 is obtained either by deleting the majority of tk coding sequences or by relocating the globin sequences from the 3' to the 5' untranslated region of the tk gene.


Assuntos
Genes Virais , Genes , Globinas/genética , RNA Mensageiro/genética , Simplexvirus/genética , Timidina Quinase/genética , Animais , Quimera , Clonagem Molecular , Enzimas de Restrição do DNA , DNA Recombinante/metabolismo , Humanos , Camundongos , Hibridização de Ácido Nucleico , Plasmídeos , Simplexvirus/enzimologia , Transfecção
14.
J Dent Res ; 96(5): 578-585, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28068493

RESUMO

Mutations in bone morphogenetic protein 1 (BMP1) in humans or deletion of BMP1 and related protease tolloid like 1 (TLL1) in mice lead to osteogenesis imperfecta (OI). Here, we show progressive periodontal defects in mice in which both BMP1 and TLL1 have been conditionally ablated, including malformed periodontal ligament (PDL) (recently shown to play key roles in normal alveolar bone formation), significant loss in alveolar bone mass ( P < 0.01), and a sharp reduction in cellular cementum. Molecular mechanism studies revealed a dramatic increase in the uncleaved precursor of type I collagen (procollagen I) and a reduction in dentin matrix protein 1 (DMP1), which is partially responsible for defects in extracellular matrix (ECM) formation and mineralization. We also showed a marked increase in the expression of matrix metallopeptidase 13 (MMP13) and tartrate-resistant acid phosphatase (TRAP), leading to an acceleration in periodontal breakdown. Finally, we demonstrated that systemic application of antibiotics significantly improved the alveolar bone and PDL damage of the knockdown phenotype, which are thus shown to be partially secondary to pathogen-induced inflammation. Together, identification of the novel roles of BMP1 and TLL1 in maintaining homeostasis of periodontal formation, partly via biosynthetic processing of procollagen I and DMP1, provides novel insights into key contributions of the extracellular matrix environment to periodontal homeostasis and contributes toward understanding of the pathology of periodontitis.


Assuntos
Proteína Morfogenética Óssea 1/fisiologia , Matriz Extracelular/metabolismo , Ligamento Periodontal/fisiologia , Periodontite/fisiopatologia , Metaloproteases Semelhantes a Toloide/fisiologia , Animais , Antibacterianos/farmacologia , Proteína Morfogenética Óssea 1/deficiência , Proteínas da Matriz Extracelular/biossíntese , Homeostase , Imuno-Histoquímica , Mandíbula , Metaloproteinase 13 da Matriz/metabolismo , Camundongos , Camundongos Knockout , Microscopia Confocal , Fenótipo , Pró-Colágeno/biossíntese , Fosfatase Ácida Resistente a Tartarato/metabolismo , Metaloproteases Semelhantes a Toloide/deficiência , Microtomografia por Raio-X
15.
Adv Dent Res ; 19(1): 57-62, 2006 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-16672551

RESUMO

The epidemiology of HIV-related oral disease in industrialized nations has evolved following the initial manifestations described in 1982. Studies from both the Americas and Europe report a decreased frequency of HIV-related oral manifestations of 10-50% following the introduction of HAART (highly active antiretroviral therapy). Evidence suggests that HAART plays an important role in controlling the occurrence of oral candidosis. The effect of HAART on reducing the incidence of oral lesions, other than oral candidosis, does not appear as significant, possibly as a result of low lesion prevalence in industrialized countries. In contrast to other oral manifestations of HIV, an increased prevalence of oral warts in patients on HAART has been reported from the USA and the UK. HIV-related salivary gland disease may show a trend of rising prevalence in the USA and Europe. The re-emergence of HIV-related oral disease may be indicative of failing therapy. A range of orofacial iatrogenic consequences of HAART has been reported, and it is often difficult to distinguish between true HIV-related oral disease manifestations and the adverse effects of HAART. A possible association between an increased risk of oral squamous cell carcinoma and HIV infection has been suggested by at least three epidemiological studies, with reference to the lip and tongue. These substantial and intensive research efforts directed toward enhancing knowledge regarding the orofacial consequences of HIV infection in the industrialized nations require dissemination in the wider health care environment.


Assuntos
Terapia Antirretroviral de Alta Atividade/efeitos adversos , Carcinoma de Células Escamosas/complicações , Países Desenvolvidos , Infecções por HIV/complicações , Doenças da Boca/complicações , Neoplasias Bucais/complicações , Candidíase Bucal/complicações , Candidíase Bucal/tratamento farmacológico , Assistência Odontológica para Doentes Crônicos/psicologia , Cárie Dentária/complicações , Europa (Continente)/epidemiologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Humanos , Doenças da Boca/tratamento farmacológico , Doenças da Boca/epidemiologia , Prevalência , Qualidade de Vida , Doenças das Glândulas Salivares/induzido quimicamente , Estados Unidos/epidemiologia , Carga Viral , Verrugas/induzido quimicamente
16.
Cancer Res ; 57(21): 4692-8, 1997 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-9354423

RESUMO

Allelic deletions involving the short arm of chromosome 3 (3p13-21.1) have been observed frequently in cervical carcinomas. Recently, a candidate tumor suppressor gene, FHIT (Fragile Histidine Triad), was cloned and mapped to this chromosomal region (3p14.2). Abnormal FHIT transcripts have been identified previously in a variety of tumor cell lines and primary carcinomas, although their significance and the molecular mechanisms underlying their origin remain incompletely defined. In addition, integration of human papillomavirus DNA has been identified at a fragile site (FRA3B) within the FHIT locus in cervical cancer. These observations motivated us to evaluate FHIT mRNA and protein expression in cervical cancer cell lines, primary cervical carcinomas, and normal tissues. Transcripts of the expected size and sequence were the predominant species identified by reverse transcription (RT)-PCR in cultured keratinocytes and all normal tissues evaluated. In contrast, aberrant FHIT transcripts were readily demonstrated in 6 of 7 cervical carcinoma cell lines and 17 of 25 (68%) primary cervical carcinomas. Northern blot analyses demonstrated reduced or absent FHIT expression in the cervical carcinoma cell lines, particularly those with aberrant RT-PCR products. Immunohistochemical analysis of Fhit expression in cervical tissues revealed strong immunoreactivity in nonneoplastic squamous and glandular cervical epithelium and marked reduction or loss of Fhit protein in 25 of 33 (76%) primary cervical carcinomas. In those cervical cancer cell lines and primary tumors with exclusively aberrant or absent FHIT transcripts by RT-PCR, Fhit protein expression was always markedly reduced or absent. The frequent alterations in FHIT expression in many cervical carcinomas, but not in normal tissues, suggest that FHIT gene alterations may play an important role in cervical tumorigenesis.


Assuntos
Hidrolases Anidrido Ácido , Carcinoma/genética , Cromossomos Humanos Par 3/genética , Deleção de Genes , Genes Supressores de Tumor/genética , Proteínas de Neoplasias , Proteínas/genética , Neoplasias do Colo do Útero/genética , Carcinoma/metabolismo , DNA Complementar/análise , Feminino , Células HeLa , Humanos , Reação em Cadeia da Polimerase , Proteínas/metabolismo , RNA Mensageiro/metabolismo , Análise de Sequência de DNA , Células Tumorais Cultivadas , Neoplasias do Colo do Útero/metabolismo
17.
Biomaterials ; 26(8): 839-48, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15353195

RESUMO

Bioactive glasses, osteoproductive materials, have received considerable attention as bone graft substitutes in the treatment of bony defects. More recent strategies for achieving a predictable periodontal regeneration include the use of enamel matrix proteins, due to their role in the formation of bone tissue. The aim of our study is to examine the effects of these materials on the proliferation and differentiation of the mouse preosteoblastic cell line MC3T3-E1. Cells were cultured up to 28 days in contact with three types of granules: Bioglass 45S5 granules (BG), 45S5 granules coated with enamel matrix proteins (Emdogain) (BG/EMD), and a less reactive glass used as a control (60S). Phase contrast microscopic observations have shown that all substrates supported the growth of osteoblastic cells. Zones of differentiation were observed at an earlier stage in cultures of BG and BG/EMD. TEM observations revealed ultrastructural features very close to what is observed in vivo during intramembranous ossification with a direct bone apposition on the bioactive glasses. Total protein production was higher in the cultures with BG and BG/EMD. Northern Blot analysis revealed a stimulation of the transcription factor Cbfa1/Runx2 at day 13 in cultures of BG when compared to the two other cultures. Bone sialoprotein (early marker of differentiation) and osteocalcin (marker of late-stage differentiation) expression was increased in cultures with BG and BG/EMD when compared to 60S. Taken together, our findings indicate that Bioglass alone or combined with Emdogain, have the ability to support the growth of osteoblast-like cells in vitro and to promote osteoblast differentiation by stimulating the expression of major phenotypic markers. In addition, we noticed that the bioactive granules coated with Emdogain revealed significantly higher protein production than the bioactive granules alone at day 20.


Assuntos
Materiais Biomiméticos , Diferenciação Celular/fisiologia , Osteoblastos/fisiologia , Biomarcadores , Cerâmica , Vidro , Microscopia Eletrônica , Microscopia de Contraste de Fase , Osteoblastos/citologia , Osteoblastos/ultraestrutura
18.
Clin Cancer Res ; 6(9): 3505-10, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10999736

RESUMO

Allelic losses involving chromosome 3p are frequently observed in cervical cancers. Deletion mapping studies of primary cervical carcinomas have localized common regions of deletion to 3p14.2 and 3p21. The candidate tumor suppressor gene FHIT has been mapped to 3p14.2, and previous studies have demonstrated reduced or aberrant FHIT transcripts and reduced or absent Fhit protein expression in a large percentage of cervical cancer-derived cell lines and primary cervical carcinomas. To expand these observations to preinvasive cervical epithelial lesions and to determine whether loss of Fhit protein expression might be associated with tumor progression, immunohistochemical methods were used to examine Fhit expression in 95 invasive cervical carcinomas, 33 high-grade squamous intraepithelial lesions (HSILs) associated with concurrent invasive cancer, 38 HSILs unassociated with invasive cancer, 24 low-grade squamous intraepithelial lesions, and 22 normal cervix samples. All normal cervical epithelia and low-grade squamous intraepithelial lesions exhibited diffuse cytoplasmic immunostaining of moderate to strong intensity. Fhit protein expression was markedly reduced or absent in 67 of 95 (71%) invasive cancers, 17 of 33 (52%) HSILs associated with invasive cancer, and 8 of 38 (21%) HSILs without associated invasive cancer. The results confirm that Fhit protein expression is reduced or absent in the majority of cervical carcinomas and suggest that loss of Fhit expression often accompanies cervical tumor progression. Moreover, absent or reduced Fhit protein is observed at a significantly higher frequency in HSILs associated with progression to invasive cancer than in HSILs with unknown risk for progression (P = 0.012). These findings suggest that loss of Fhit expression in HSILs could serve as a useful marker of high-grade preinvasive lesions that have an increased likelihood of progression to invasive carcinoma.


Assuntos
Hidrolases Anidrido Ácido , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Proteínas de Neoplasias , Biossíntese de Proteínas , Displasia do Colo do Útero/metabolismo , Displasia do Colo do Útero/patologia , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia , Biomarcadores Tumorais/biossíntese , Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/genética , Progressão da Doença , Feminino , Expressão Gênica , Humanos , Imuno-Histoquímica , Invasividade Neoplásica , Proteínas/genética , Neoplasias do Colo do Útero/genética , Displasia do Colo do Útero/genética
19.
Arch Intern Med ; 156(19): 2249-54, 1996 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-8885825

RESUMO

BACKGROUND: Because human immunodeficiency virus (HIV) infection affects an increasing number of women in the United States, we investigated the role played by gender in the occurrence of HIV-related oral conditions. METHODS: As part of a 4-year prospective study of 3 epidemiological cohorts, oral and physical examinations (including blood tests) were performed on HIV-infected men (n = 200) and women (n = 218) at 6-month intervals. Our outcome variables included oral conditions commonly associated with HIV infection: hairy leukoplakia, candidiasis, ulcers, warts, non-Hodgkin lymphoma, Kaposi sarcoma, and parotid enlargement. RESULTS: Only hairy leukoplakia, candidiasis, and ulcers were observed. The occurrence of hairy leukoplakia and candidiasis was higher in men (22% and 24%, respectively) than in women (9% and 13%, respectively) during the study period. A regression model for longitudinal data (generalized estimating equation) disclosed that the odds of having hairy leukoplakia were 2.5 times higher for men than for women, after controlling for CD4+ cell count, race, and injecting drug use (95% confidence interval, 1.34-4.76; P = .003). Length of follow-up did not confound this association. A weaker association was found between the occurrence of oral candidiasis and gender (adjusted odds ratio, 1.85; 95% confidence interval, 1.0-3.43; P = .05). CONCLUSIONS: In this sample of HIV-infected adults, we found that men were significantly more likely to have hairy leukoplakia than were women. The hairy leukoplakia-gender association merits further investigation, because it may be related to a gender difference in the mode of expression of Epstein-Barr virus.


Assuntos
Infecções por HIV/complicações , Leucoplasia Pilosa/etiologia , Adulto , Candidíase Bucal/etiologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Razão de Chances , Úlceras Orais/etiologia , Fatores de Risco , Fatores Sexuais
20.
AIDS ; 5(11): 1339-43, 1991 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1768382

RESUMO

Candidiasis is the most common oral fungal infection seen in association with HIV infection. It may present in a number of clinical forms, including pseudomembranous and erythematous candidiasis. To determine whether erythematous candidiasis, like the pseudomembranous form, is predictive of the development of AIDS, we reviewed the records of 169 HIV-seropositive patients seen at clinic of the Oral AIDS Center, University of California, San Francisco who were diagnosed with pseudomembranous or erythematous (or both) forms of oral candidiasis at their first examination. Kaplan-Meier analysis showed a rapid rate of progression to AIDS (median, 25 months) and to death (median, 43.8 months) in all three groups. We conclude that erythematous candidiasis is as serious a prognostic indicator as pseudomembranous candidiasis. Because the erythematous form is more difficult to recognize and hence is underdiagnosed, efforts should be made to teach non-dental clinicians who care for HIV-infected patients to diagnose and treat this lesion.


Assuntos
Candidíase Bucal/complicações , Infecções por HIV/complicações , Infecções Oportunistas/complicações , Síndrome da Imunodeficiência Adquirida/complicações , Síndrome da Imunodeficiência Adquirida/mortalidade , Candidíase Bucal/classificação , Candidíase Bucal/diagnóstico , Humanos , Infecções Oportunistas/diagnóstico , Prognóstico , Taxa de Sobrevida , Fatores de Tempo
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