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1.
Mol Divers ; 27(4): 1767-1783, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36197552

RESUMO

A facile protocol was developed for the combinatorial synthesis of furo[2,3-d]pyrimidinone and pyrrolo[2,3-d]pyrimidinone library via a one-pot condensation, from 2-amino furans/pyrroles. Herein reported process required a similar reaction condition, providing mild access to two diverse series of natural product-like heterocycles. Both furo[2,3-d]pyrimidinones and pyrrolo[2,3-d]pyrimidinones were evaluated in vitro against a panel of human cancer cell lines including against human cancer HeLa (cervical), MCF-7 (breast) and HT-29 (colon) cell lines. Derivative 12n ((2-(4-chlorophenyl)-1-methyl-6,7,8,9-tetrahydropyrido[1,2-a]pyrrolo[2,3-d]pyrimidin-4(1H)-one)) showed high activity (IC50 = 6.55 ± 0.31 µM) against the HeLa cell line. These products could be subjected to a various modification and therefore represent important skeletons for the anticancer drug discovery.


Assuntos
Antineoplásicos , Pirimidinonas , Humanos , Pirimidinonas/farmacologia , Estrutura Molecular , Relação Estrutura-Atividade , Células HeLa , Antineoplásicos/farmacologia
2.
Chem Biodivers ; 20(3): e202201059, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36680784

RESUMO

The chemical transformation of the tricyclic furo[2,3-d]pyrimidines was performed under isosteric and scaffold-hopping strategies focusing on the synthesis of its arylidene and imine-containing derivatives. Naturally-occurring alkaloids mackinazolinone and isaindigotone were as templates of target heterocycles. Synthesized compounds evaluated for their antitumor activity on human cancer cervical HeLa, breast MCF-7, and colon HT-29 cell lines. Four compounds: 8c, 8e, 10b, and 10c demonstrated potency against HeLa and HT-29 cell lines, and IC50 values were between 7.37-13.72 µM, respectively. The molecular docking results showed that compounds 8c and 10b had good binding and high matching with the target EGFR protein.


Assuntos
Alcaloides , Antineoplásicos , Humanos , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade , Antineoplásicos/química , Pirimidinas/química , Ensaios de Seleção de Medicamentos Antitumorais , Alcaloides/farmacologia , Estrutura Molecular , Linhagem Celular Tumoral , Proliferação de Células , Desenho de Fármacos
3.
J Med Internet Res ; 23(11): e28946, 2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34751659

RESUMO

BACKGROUND: Nonvalvular atrial fibrillation (NVAF) affects almost 6 million Americans and is a major contributor to stroke but is significantly undiagnosed and undertreated despite explicit guidelines for oral anticoagulation. OBJECTIVE: The aim of this study is to investigate whether the use of semisupervised natural language processing (NLP) of electronic health record's (EHR) free-text information combined with structured EHR data improves NVAF discovery and treatment and perhaps offers a method to prevent thousands of deaths and save billions of dollars. METHODS: We abstracted 96,681 participants from the University of Buffalo faculty practice's EHR. NLP was used to index the notes and compare the ability to identify NVAF, congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, stroke or transient ischemic attack, vascular disease, age 65 to 74 years, sex category (CHA2DS2-VASc), and Hypertension, Abnormal liver/renal function, Stroke history, Bleeding history or predisposition, Labile INR, Elderly, Drug/alcohol usage (HAS-BLED) scores using unstructured data (International Classification of Diseases codes) versus structured and unstructured data from clinical notes. In addition, we analyzed data from 63,296,120 participants in the Optum and Truven databases to determine the NVAF frequency, rates of CHA2DS2­VASc ≥2, and no contraindications to oral anticoagulants, rates of stroke and death in the untreated population, and first year's costs after stroke. RESULTS: The structured-plus-unstructured method would have identified 3,976,056 additional true NVAF cases (P<.001) and improved sensitivity for CHA2DS2-VASc and HAS-BLED scores compared with the structured data alone (P=.002 and P<.001, respectively), causing a 32.1% improvement. For the United States, this method would prevent an estimated 176,537 strokes, save 10,575 lives, and save >US $13.5 billion. CONCLUSIONS: Artificial intelligence-informed bio-surveillance combining NLP of free-text information with structured EHR data improves data completeness, prevents thousands of strokes, and saves lives and funds. This method is applicable to many disorders with profound public health consequences.


Assuntos
Fibrilação Atrial , Acidente Vascular Cerebral , Idoso , Anticoagulantes , Inteligência Artificial , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/prevenção & controle , Estudos de Casos e Controles , Registros Eletrônicos de Saúde , Humanos , Processamento de Linguagem Natural , Medição de Risco , Fatores de Risco , Acidente Vascular Cerebral/prevenção & controle
4.
PLoS Genet ; 12(10): e1006352, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27741240

RESUMO

TGFßs act through canonical and non-canonical pathways, and canonical signals are transduced via Smad2 and Smad3. However, the contribution of canonical vs. non-canonical pathways in cartilage is unknown because the role of Smad2 in chondrogenesis has not been investigated in vivo. Therefore, we analyzed mice in which Smad2 is deleted in cartilage (Smad2CKO), global Smad3-/- mutants, and crosses of these strains. Growth plates at birth from all mutant strains exhibited expanded columnar and hypertrophic zones, linked to increased proliferation in resting chondrocytes. Defects were more severe in Smad2CKO and Smad2CKO;Smad3-/- (Smad2/3) mutant mice than in Smad3-/- mice, demonstrating that Smad2 plays a role in chondrogenesis. Increased levels of Ihh RNA, a key regulator of chondrocyte proliferation and differentiation, were seen in prehypertrophic chondrocytes in the three mutant strains at birth. In accordance, TGFß treatment decreased Ihh RNA levels in primary chondrocytes from control (Smad2fx/fx) mice, but inhibition was impaired in cells from mutants. Consistent with the skeletal phenotype, the impact on TGFß-mediated inhibition of Ihh RNA expression was more severe in Smad2CKO than in Smad3-/- cells. Putative Smad2/3 binding elements (SBEs) were identified in the proximal Ihh promoter. Mutagenesis demonstrated a role for three of them. ChIP analysis suggested that Smad2 and Smad3 have different affinities for these SBEs, and that the repressors SnoN and Ski were differentially recruited by Smad2 and Smad3, respectively. Furthermore, nuclear localization of the repressor Hdac4 was decreased in growth plates of Smad2CKO and double mutant mice. TGFß induced association of Hdac4 with Smad2, but not with Smad3, on the Ihh promoter. Overall, these studies revealed that Smad2 plays an essential role in the development of the growth plate, that both Smads 2 and 3 inhibit Ihh expression in the neonatal growth plate, and suggested they accomplish this by binding to distinct SBEs, mediating assembly of distinct repressive complexes.


Assuntos
Diferenciação Celular/genética , Proliferação de Células/genética , Condrogênese/genética , Proteína Smad2/genética , Proteína Smad3/genética , Animais , Cartilagem/crescimento & desenvolvimento , Cartilagem/metabolismo , Condrócitos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Lâmina de Crescimento/crescimento & desenvolvimento , Proteínas Hedgehog/genética , Histona Desacetilases/genética , Camundongos , Regiões Promotoras Genéticas , Fator de Crescimento Transformador beta/genética
5.
Mycopathologia ; 182(7-8): 733-737, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28213800

RESUMO

Invasive aspergillosis can be difficult to diagnose, and early recognition and initiation of therapy is imperative for improving patient outcomes. A case of invasive Aspergillus laryngotracheobronchitis is presented here with a review of the relevant literature. A 58-year-old male undergoing treatment for CNS lymphoma presented with neutropenic sepsis and acute respiratory distress requiring intubation. Following extubation, he reported persistent hoarseness for 1-month duration and he was found to have pseudomembranous plaques and ulcers of the larynx, trachea, and right mainstem bronchus consistent with Aspergillus laryngotracheobronchitis. Invasive Aspergillus laryngotracheobronchitis should be considered in immunocompromised patients presenting with persistent hoarseness.


Assuntos
Aspergilose/diagnóstico , Aspergillus/isolamento & purificação , Neoplasias do Sistema Nervoso Central/complicações , Infecções Fúngicas Invasivas/diagnóstico , Linfoma/complicações , Infecções Respiratórias/complicações , Aspergilose/microbiologia , Aspergilose/patologia , Humanos , Infecções Fúngicas Invasivas/microbiologia , Infecções Fúngicas Invasivas/patologia , Masculino , Pessoa de Meia-Idade
6.
Curr Org Synth ; 18(4): 399-405, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33371849

RESUMO

AIM: To develop anti-cancer active pharmaceutical intermediates. BACKGROUND: Acridone derivatives possess a wide range of pharmacological activities: 1) they intercalate DNA and 2) form a covalent bond with DNA. OBJECTIVE: To screen in vitro anti-cancer activity against Cdc25b and SHP1 of new acridone derivatives and preliminary study on the structure-activity relationship. MATERIALS AND METHODS: The synthesis of new acridone derivatives and in vitro evaluation of their anti-cancer activity on Cdc25b and SHP1 was achieved. Natural products that contain acridine structures, such as cystodytin A and acronycine, are isolated from certain marine (tunicates & ascidians, sponges, sea anemones) and plant (bark of Australian scrub ash tree) species. Herein, we report the efficient one-pot green synthesis of twelve novel 3,4-dihydro-1 (2H) acridone derivatives, using montmorillonite K10 as the catalyst and iron/citric acid in water. Also, their inhibitory activity against Cdc25B and SHP1 is examined, in which specific derivatives show enhanced inhibitory activity compared to others. RESULTS AND DISCUSSION: Twelve new acridone derivatives were prepared, starting from 2-nitrobenzaldehyde derivatives and 1, 3-cyclohexanedione derivatives, which exhibited substantial anti-cancer activity against Cdc25b and SHP1 cells. CONCLUSION: Preliminary studies on the structure-activity relationship have shown the influence of the structural parameters and, in particular, the nature of the substituent on aromatic ring structure and cyclohexanone. Other: Further study on the structure-activity relationship is required.


Assuntos
Acridinas , Neoplasias , Acridinas/farmacologia , Austrália , Humanos , Proteína Tirosina Fosfatase não Receptora Tipo 6 , Relação Estrutura-Atividade , Fosfatases cdc25
7.
Stud Health Technol Inform ; 251: 59-62, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29968601

RESUMO

BMI Investigator (BMII) is an interactive web-based tool with a learning knowledge base, which provides a way for researchers to query structured, unstructured, genomic and image data contained in a data warehouse. We demonstrate how development of an efficient, usable, and learnable web interface for a diverse group of research stakeholders benefits from an iterative human-centered participatory design process utilizing a team of clinicians, students, programmers, and informatics experts.


Assuntos
Data Warehousing , Internet , Bases de Conhecimento , Interface Usuário-Computador , Ergonomia , Humanos , Aprendizagem , Pesquisa , Estudantes
8.
Stud Health Technol Inform ; 241: 165-172, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28809201

RESUMO

In a retrospective secondary-use EHR study identifying a cohort of Non-Valvular Atrial Fibrillation (NVAF) patients, chart abstraction was done by two sets of clinicians to create a gold standard for risk measures CHA2DS2-VASc and HAS-BLED. Inter-rater reliability between each set of clinicians for NVAF and the outcomes of interest were variable, ranging from extremely low agreement to high agreement. To assess the chart abstraction process, a focus group and a survey was conducted. Survey findings revealed patterns of difficulty in assessing certain items dealing with temporality and social data. The focus group raised issues on the quality and completeness of EHR data, including missing encounters, truncated notes, and low granularity. It also raised the issue of the usability of the data system, the Clinical Data Viewer, which did not mirror a live EHR and made it difficult to record outcomes. Finally, the focus group found it was difficult to infer certain outcomes, like severity, from the provided data. These factors produced differences in clinician rated outcomes.


Assuntos
Fibrilação Atrial , Registros Eletrônicos de Saúde , Humanos , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Estudos Retrospectivos , Inquéritos e Questionários
9.
AMIA Annu Symp Proc ; 2017: 1913-1922, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29854263

RESUMO

Patient portal and personal health record adoption and usage rates have been suboptimal. A systematic review of the literature was performed to capture all published studies that specifically addressed barriers, facilitators, and solutions to optimal patient portal and personal health record enrollment and use. Consistent themes emerged from the review. Patient attitudes were critical as either barrier or facilitator. Institutional buy-in, information technology support, and aggressive tailored marketing were important facilitators. Interface redesign was a popular solution. Quantitative studies identified many barriers to optimal patient portal and personal health record enrollment and use, and qualitative and mixed methods research revealed thoughtful explanations for why they existed. Our study demonstrated the value of qualitative and mixed research methodologies in understanding the adoption of consumer health technologies. Results from the systematic review should be used to guide the design and implementation of future patient portals and personal health records, and ultimately, close the digital divide.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Registros de Saúde Pessoal , Portais do Paciente , Informática Aplicada à Saúde dos Consumidores , Registros Eletrônicos de Saúde , Humanos , Portais do Paciente/estatística & dados numéricos
10.
J Bone Miner Res ; 26(4): 747-60, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20954177

RESUMO

One of the goals of systems genetics is the reconstruction of gene networks that underlie key processes in development and disease. To identify cartilage gene networks that play an important role in bone development, we used a systems genetics approach that integrated microarray gene expression profiles from cartilage and bone phenotypic data from two sets of recombinant inbred strains. Microarray profiles generated from isolated chondrocytes were used to generate weighted gene coexpression networks. This analysis resulted in the identification of subnetworks (modules) of coexpressed genes that then were examined for relationships with bone geometry and density. One module exhibited significant correlation with femur length (r = 0.416), anteroposterior diameter (r = 0.418), mediolateral diameter (r = 0.576), and bone mineral density (r = 0.475). Highly connected genes (n = 28) from this and other modules were tested in vitro using prechondrocyte ATDC5 cells and RNA interference. Five of the 28 genes were found to play a role in chondrocyte differentiation. Two of these, Hspd1 and Cdkn1a, were known previously to function in chondrocyte development, whereas the other three, Bhlhb9, Cugbp1, and Spcs3, are novel genes. Our integrative analysis provided a systems-level view of cartilage development and identified genes that may be involved in bone development.


Assuntos
Diferenciação Celular/fisiologia , Condrócitos/citologia , Redes Reguladoras de Genes/fisiologia , Genômica/métodos , Biologia de Sistemas/métodos , Animais , Animais Recém-Nascidos , Densidade Óssea , Osso e Ossos/embriologia , Osso e Ossos/metabolismo , Proteínas CELF1 , Cartilagem/embriologia , Cartilagem/metabolismo , Linhagem Celular , Chaperonina 60/genética , Condrócitos/metabolismo , Condrogênese/fisiologia , Cromossomos/genética , Colágeno/genética , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Inibidor de Quinase Dependente de Ciclina p21/genética , Embrião de Mamíferos/metabolismo , Fêmur/anatomia & histologia , Fêmur/química , Expressão Gênica/genética , Perfilação da Expressão Gênica/métodos , Glicosaminoglicanos/metabolismo , Fator de Crescimento Semelhante a EGF de Ligação à Heparina , Peptídeos e Proteínas de Sinalização Intercelular/genética , Funções Verossimilhança , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Camundongos Transgênicos , Proteínas Mitocondriais/genética , Análise de Sequência com Séries de Oligonucleotídeos , Osteoblastos/metabolismo , Locos de Características Quantitativas/genética , RNA Interferente Pequeno/genética , Proteínas de Ligação a RNA/genética , Células-Tronco/citologia , Células-Tronco/metabolismo
11.
Cytokine Growth Factor Rev ; 20(5-6): 379-88, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19926329

RESUMO

Smad proteins are intracellular molecules that mediate the canonical signaling cascade of TGFbeta superfamily growth factors. The TGFbeta superfamily comprises two groups of growth factors, BMPs and TGFbetas. Both groups can be further divided into several sub-groups based on sequence homologies and functional similarities. Ligands of the TGFbeta superfamily bind to cell surface receptors to activate Smad proteins in the cytoplasm; then the activated Smad proteins translocate into the nucleus to activate or repress specific target gene transcription. Both groups of growth factors play important roles in skeletal development and regeneration. However, whether these effects reflect signaling through canonical Smad pathways, or other non-canonical signaling pathways in vivo remains a mystery. Moreover, the mechanisms utilized by Smad proteins to initiate nuclear events and their interactions with cytoplasmic proteins are still under intensive investigation. This review will discuss the most recent progress understanding Smad signaling in the context of skeletal development and regeneration.


Assuntos
Desenvolvimento Ósseo/genética , Regeneração Óssea/genética , Proteínas Smad/fisiologia , Animais , Desenvolvimento Ósseo/fisiologia , Regeneração Óssea/fisiologia , Condrogênese/genética , Condrogênese/fisiologia , Humanos , Modelos Biológicos , Osteogênese/genética , Osteogênese/fisiologia , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Proteínas Smad/genética , Proteínas da Superfamília de TGF-beta/genética , Proteínas da Superfamília de TGF-beta/fisiologia
12.
Development ; 136(7): 1093-104, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19224984

RESUMO

Bone morphogenetic protein (BMP) signaling is required for endochondral bone formation. However, whether or not the effects of BMPs are mediated via canonical Smad pathways or through noncanonical pathways is unknown. In this study we have determined the role of receptor Smads 1, 5 and 8 in chondrogenesis. Deletion of individual Smads results in viable and fertile mice. Combined loss of Smads 1, 5 and 8, however, results in severe chondrodysplasia. Smad1/5(CKO) (cartilage-specific knockout) mutant mice are nearly identical to Smad1/5(CKO);Smad8(-/-) mutants, indicating that Smads 1 and 5 have overlapping functions and are more important than Smad8 in cartilage. The Smad1/5(CKO) phenotype is more severe than that of Smad4(CKO) mice, challenging the dogma, at least in chondrocytes, that Smad4 is required to mediate Smad signaling through BMP pathways. The chondrodysplasia in Smad1/5(CKO) mice is accompanied by imbalances in cross-talk between the BMP, FGF and Ihh/PTHrP pathways. We show that Ihh is a direct target of BMP pathways in chondrocytes, and that FGF exerts antagonistic effects on Ihh expression. Finally, we tested whether FGF exerts its antagonistic effects directly through Smad linker phosphorylation. The results support the alternative conclusion that the effects of FGFs on BMP signaling are indirect in vivo.


Assuntos
Proteínas Morfogenéticas Ósseas/fisiologia , Osteogênese/fisiologia , Proteína Smad1/fisiologia , Proteína Smad5/fisiologia , Animais , Diferenciação Celular , Proliferação de Células , Sobrevivência Celular , Condrócitos/citologia , Condrócitos/fisiologia , Condrogênese/genética , Condrogênese/fisiologia , Extremidades/embriologia , Feminino , Fatores de Crescimento de Fibroblastos/fisiologia , Proteínas Hedgehog/fisiologia , Masculino , Camundongos , Camundongos Knockout , Camundongos Mutantes , Osteogênese/genética , Proteína Relacionada ao Hormônio Paratireóideo/fisiologia , Fosforilação , Transdução de Sinais , Proteína Smad1/deficiência , Proteína Smad1/genética , Proteína Smad4/deficiência , Proteína Smad4/genética , Proteína Smad4/fisiologia , Proteína Smad5/deficiência , Proteína Smad5/genética , Proteína Smad8/deficiência , Proteína Smad8/genética , Proteína Smad8/fisiologia
13.
Dev Biol ; 305(1): 202-16, 2007 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-17359961

RESUMO

In the post-natal growth plate, chondrocytes are arranged in columns parallel to the long axis of the bone. Chondrocytes divide perpendicular to this axis and then move into position one on top of another in a process called "rotation" that maintains columnar organization. Primary cilia are non-motile microtubule base appendages extending from the surface of almost all vertebrate cells. Primary cilia were described on chondrocytes almost 40 years ago but the function of these structures in cartilage biology is not known. Intraflagellar transport (IFT) is the process by which primary cilia are generated and maintained. This study tested the hypothesis that IFT plays an important role in post-natal skeletal development. Kif3a, a subunit of the Kinesin II motor complex, that is required for intraflagellar transport and the formation of cilia, was deleted in mouse chondrocytes via Col2a-Cre-mediated recombination. Disruption of IFT resulted in subsequent depletion of cilia and post-natal dwarfism due to premature loss of the growth plate likely a result of reduced proliferation and accelerated hypertrophic differentiation of chondrocytes. Cell shape and columnar orientation in the growth plate were also disrupted suggesting a defect in the process of rotation. Alterations in chondrocyte rotation were accompanied by disruption of the actin cytoskeleton and alterations in the localization of activated FAK to focal adhesion-like structures on chondrocytes. This is the first report indicating a role for IFT and primary cilia in the development of the post-natal growth plate. The results suggest a model in which IFT/cilia act to maintain the columnar organization of the growth plate via the process of chondrocyte rotation.


Assuntos
Movimento Celular/fisiologia , Condrócitos/fisiologia , Cílios/metabolismo , Lâmina de Crescimento/crescimento & desenvolvimento , Cinesinas/metabolismo , Agrecanas/metabolismo , Animais , Diferenciação Celular/fisiologia , Colágeno Tipo X/metabolismo , Primers do DNA , Lâmina de Crescimento/diagnóstico por imagem , Imuno-Histoquímica , Hibridização In Situ , Cinesinas/genética , Camundongos , Camundongos Transgênicos , Radiografia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
14.
Development ; 134(2): 307-16, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17166921

RESUMO

While cilia are present on most cells in the mammalian body, their functional importance has only recently been discovered. Cilia formation requires intraflagellar transport (IFT), and mutations disrupting the IFT process result in loss of cilia and mid-gestation lethality with developmental defects that include polydactyly and abnormal neural tube patterning. The early lethality in IFT mutants has hindered research efforts to study the role of this organelle at later developmental stages. Thus, to investigate the role of cilia during limb development, we generated a conditional allele of the IFT protein Ift88 (polaris). Using the Cre-lox system, we disrupted cilia on different cell populations within the developing limb. While deleting cilia in regions of the limb ectoderm had no overt effect on patterning, disruption in the mesenchyme resulted in extensive polydactyly with loss of anteroposterior digit patterning and shortening of the proximodistal axis. The digit patterning abnormalities were associated with aberrant Shh pathway activity, whereas defects in limb outgrowth were due in part to disruption of Ihh signaling during endochondral bone formation. In addition, the limbs of mesenchymal cilia mutants have ectopic domains of cells that resemble chondrocytes derived from the perichondrium, which is not typical of Indian hedgehog mutants. Overall these data provide evidence that IFT is essential for normal formation of the appendicular skeleton through disruption of multiple signaling pathways.


Assuntos
Desenvolvimento Ósseo/fisiologia , Flagelos/fisiologia , Animais , Padronização Corporal/genética , Desenvolvimento Ósseo/genética , Proteínas de Transporte/genética , Proteínas de Transporte/fisiologia , Cílios/fisiologia , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Hibridização In Situ , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Camundongos , Camundongos Knockout , Camundongos Mutantes , Camundongos Transgênicos , Mutação , Fenótipo , Polidactilia/embriologia , Polidactilia/genética , Gravidez , Proteínas Supressoras de Tumor/deficiência , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/fisiologia
15.
Development ; 134(11): 2159-69, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17507416

RESUMO

The motor protein Kif3a and primary cilia regulate important developmental processes, but their roles in skeletogenesis remain ill-defined. Here we created mice deficient in Kif3a in cartilage and focused on the cranial base and synchondroses. Kif3a deficiency caused cranial base growth retardation and dysmorphogenesis, which were evident in neonatal animals by anatomical and micro-computed tomography (microCT) inspection. Kif3a deficiency also changed synchondrosis growth plate organization and function, and the severity of these changes increased over time. By postnatal day (P)7, mutant growth plates lacked typical zones of chondrocyte proliferation and hypertrophy, and were instead composed of chondrocytes with an unusual phenotype characterized by strong collagen II (Col2a1) gene expression but barely detectable expression of Indian hedgehog (Ihh), collagen X (Col10a1), Vegf (Vegfa), MMP-13 (Mmp13) and osterix (Sp7). Concurrently, unexpected developmental events occurred in perichondrial tissues, including excessive intramembranous ossification all along the perichondrial border and the formation of ectopic cartilage masses. Looking for possible culprits for these latter processes, we analyzed hedgehog signalling topography and intensity by monitoring the expression of the hedgehog effectors Patched 1 and Gli1, and of the hedgehog-binding cell-surface component syndecan 3. Compared with controls, hedgehog signaling was quite feeble within mutant growth plates as early as P0, but was actually higher and was widespread all along mutant perichondrial tissues. Lastly, we studied postnatal mice deficient in Ihh in cartilage; their cranial base defects only minimally resembled those in Kif3a-deficient mice. In summary, Kif3a and primary cilia make unique contributions to cranial base development and synchondrosis growth plate function. Their deficiency causes abnormal topography of hedgehog signaling, growth plate dysfunction, and un-physiologic responses and processes in perichondrial tissues, including ectopic cartilage formation and excessive intramembranous ossification.


Assuntos
Cartilagem/embriologia , Lâmina de Crescimento/fisiopatologia , Proteínas Hedgehog/metabolismo , Cinesinas/deficiência , Morfogênese/genética , Transdução de Sinais/fisiologia , Crânio/embriologia , Animais , Cartilagem/metabolismo , Lâmina de Crescimento/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Camundongos , Receptores Patched , Receptor Patched-1 , Receptores de Superfície Celular/metabolismo , Sindecana-3/metabolismo , Tomografia Computadorizada por Raios X , Proteína GLI1 em Dedos de Zinco
16.
EMBO Rep ; 4(4): 374-80, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12671681

RESUMO

Mesenchymal stem cells have the potential to differentiate into various cell lineages, including adipocytes and osteoblasts. The induction of adipocyte differentiation by glucocorticoids (GCs) not only causes the accumulation of fat cells in bone marrow, but also depletes the supply of osteoblasts for new bone formation, thus leading to osteoporosis. We have shown that a GC-induced leucine-zipper protein (GILZ) antagonizes adipocyte differentiation. GILZ binds to a tandem repeat of CCAAT/enhancer-binding protein (C/EBP) binding sites in the promoter of the gene encoding peroxisome-proliferator-activated receptor-gamma2 (PPAR-gamma2), and inhibits its transcription as a sequence-specific transcriptional repressor. We have also shown that ectopic expression of GILZ blocks GC-induced adipocyte differentiation. Furthermore, adipogenic marker genes (for example, those encoding PPAR-gamma2, C/EBP-alpha, lipoprotein lipase and adipsin) are also inhibited by GILZ. Our results reveal a novel GC antagonistic mechanism that has potential therapeutic applications for the inhibition of GC-induced adipocyte differentiation.


Assuntos
Adipócitos/citologia , Diferenciação Celular/efeitos dos fármacos , Dexametasona/farmacologia , Glucocorticoides/farmacologia , Mesoderma/citologia , Fatores de Transcrição/genética , Células 3T3 , Adipócitos/efeitos dos fármacos , Animais , Sítios de Ligação , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Proteínas de Ligação a DNA/genética , Zíper de Leucina , Mesoderma/efeitos dos fármacos , Mesoderma/fisiologia , Camundongos , Receptores Citoplasmáticos e Nucleares/efeitos dos fármacos , Receptores Citoplasmáticos e Nucleares/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição/efeitos dos fármacos , Fatores de Transcrição/fisiologia
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