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1.
Ultrasound Obstet Gynecol ; 58(5): 698-704, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33030757

RESUMO

OBJECTIVE: A model that can predict reliably the risk of pre-eclampsia (PE)-related pregnancy complications does not exist. The aim of this study was to develop and validate internally a clinical prediction model to predict the risk of a composite outcome of PE-related maternal and fetal complications within 7, 14 and 30 days of testing in women with suspected or confirmed PE. METHODS: The data for this study were derived from a prospective, multicenter, observational cohort study on women with a singleton pregnancy and suspected or confirmed PE at 20 to < 37 weeks' gestation. For the development of the prediction model, the possible contribution of clinical and standard laboratory variables, as well as the biomarkers soluble fms-like tyrosine kinase-1 (sFlt-1), placental growth factor (PlGF) and their ratio, in the prediction of a composite outcome of PE-related complications, consisting of maternal and fetal adverse events within 7, 14 and 30 days, was explored using multivariable competing-risks regression analysis. The discriminative ability of the model was assessed using the concordance (c-) statistic. A bootstrap validation procedure with 500 replications was used to correct the estimate of the prediction model performance for optimism and to compute a shrinkage factor for the regression coefficients to correct for overfitting. RESULTS: Among 384 women with suspected or confirmed PE, 96 (25%) had an adverse PE-related outcome at any time after hospital admission. Important predictors of adverse PE-related outcome included sFlt-1/PlGF ratio, gestational age at the time of biomarker measurement and protein-to-creatinine ratio as continuous variables. The c-statistics (corrected for optimism) for developing a PE-related complication within 7, 14 and 30 days were 0.89, 0.88 and 0.87, respectively. There was limited overfitting, as indicated by a shrinkage factor of 0.91. CONCLUSIONS: We propose a simple clinical prediction model with good discriminative performance to predict PE-related complications. Determination of its usefulness in clinical practice awaits further investigation and external validation. © 2020 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Modelos Estatísticos , Pré-Eclâmpsia/sangue , Complicações na Gravidez/diagnóstico , Diagnóstico Pré-Natal/métodos , Adulto , Biomarcadores/análise , Feminino , Idade Gestacional , Humanos , Fator de Crescimento Placentário/sangue , Pré-Eclâmpsia/prevenção & controle , Valor Preditivo dos Testes , Gravidez , Complicações na Gravidez/etiologia , Complicações na Gravidez/prevenção & controle , Trimestres da Gravidez/sangue , Estudos Prospectivos , Análise de Regressão , Reprodutibilidade dos Testes , Medição de Risco , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/sangue
2.
Br J Dermatol ; 183(3): 495-502, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-31856292

RESUMO

BACKGROUND: Patients with actinic keratosis (AK) are at increased risk for developing keratinocyte carcinoma (KC) but predictive factors and their risk rates are unknown. OBJECTIVES: To develop and internally validate a prediction model to calculate the absolute risk of a first KC in patients with AK. METHODS: The risk-prediction model was based on the prospective population-based Rotterdam Study cohort. We hereto analysed the data of participants with at least one AK lesion at cohort baseline using a multivariable Cox proportional hazards model and included 13 a priori defined candidate predictor variables considering phenotypic, genetic and lifestyle risk factors. KCs were identified by linkage of the data with the Dutch Pathology Registry. RESULTS: Of the 1169 AK participants at baseline, 176 (15·1%) developed a KC after a median follow-up of 1·8 years. The final model with significant predictors was obtained after backward stepwise selection and comprised the presence of four to nine AKs [hazard ratio (HR) 1·68, 95% confidence interval (CI) 1·17-2·42], 10 or more AKs (HR 2·44, 95% CI 1·65-3·61), AK localization on the upper extremities (HR 0·75, 95% CI 0·52-1·08) or elsewhere except the head (HR 1·40, 95% CI 0·98-2·01) and coffee consumption (HR 0·92, 95% CI 0·84-1·01). Evaluation of the discriminative ability of the model showed a bootstrap validated concordance index (c-index) of 0·60. CONCLUSIONS: We showed that the risk of KC in patients with AK can be calculated with the use of four easily assessable predictor variables. Given the c-index, extension of the model with additional, currently unknown predictor variables is desirable. Linked Comment: Kim et al. Br J Dermatol 2020; 183:415-416.


Assuntos
Carcinoma , Ceratose Actínica , Humanos , Queratinócitos , Ceratose Actínica/epidemiologia , Estudos Prospectivos , Fatores de Risco
3.
Mol Psychiatry ; 17(4): 421-32, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21358712

RESUMO

We used genome-wide single nucleotide polymorphism (SNP) data to search for the presence of copy number variants (CNVs) in 882 patients with bipolar disorder (BD) and 872 population-based controls. A total of 291 (33%) patients had an early age-at-onset < or =21 years (AO < or =21 years). We systematically filtered for CNVs that cover at least 30 consecutive SNPs and which directly affect at least one RefSeq gene. We tested whether (a) the genome-wide burden of these filtered CNVs differed between patients and controls and whether (b) the frequency of specific CNVs differed between patients and controls. Genome-wide burden analyses revealed that the frequency and size of CNVs did not differ substantially between the total samples of BD patients and controls. However, separate analysis of patients with AO < or =21 years and AO>21 years showed that the frequency of microduplications was significantly higher (P=0.0004) and the average size of singleton microdeletions was significantly larger (P=0.0056) in patients with AO < or =21 years compared with controls. A search for specific BD-associated CNVs identified two common CNVs: (a) a 160 kb microduplication on 10q11 was overrepresented in AO < or = 21 years patients (9.62%) compared with controls (3.67%, P=0.0005) and (b) a 248 kb microduplication on 6q27 was overrepresented in the AO< or = 21 years subgroup (5.84%) compared with controls (2.52%, P=0.0039). These data suggest that CNVs have an influence on the development of early-onset, but not later-onset BD. Our study provides further support for previous hypotheses of an etiological difference between early-onset and later-onset BD.


Assuntos
Transtorno Bipolar/epidemiologia , Transtorno Bipolar/genética , Variações do Número de Cópias de DNA/genética , Predisposição Genética para Doença/genética , Adulto , Fatores Etários , Idade de Início , Transtorno Bipolar/diagnóstico , Estudos de Casos e Controles , Bases de Dados Genéticas , Feminino , Estudo de Associação Genômica Ampla/métodos , Alemanha/epidemiologia , Humanos , Masculino , Polimorfismo de Nucleotídeo Único/genética
4.
Br J Dermatol ; 165(6): 1293-302, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22032556

RESUMO

BACKGROUND: Male-pattern baldness (androgenetic alopecia, AGA) is the most common form of hair loss among humans. Research has shown that it is caused by genetic factors. Numerous studies have unequivocally identified two major genetic risk loci for AGA: the X-chromosomal AR/EDA2R locus, and the PAX1/FOXA2 locus on chromosome 20. OBJECTIVES: To identify further candidate genes for AGA, and thus gain further insights into this phenotype. METHODS: A German sample of 581 severely affected cases and 617 controls was used to perform a genome-wide association study. The identified associated locus was further analysed by fine-mapping, and then independently replicated in an Australian sample. Expression and pathway analyses were performed to characterize the susceptibility gene identified. RESULTS: The most significant association signal was obtained for rs756853 (P = 1·64 × 10(-7) ), which is located intronically in the histone deacetylase 9 (HDAC9) gene. Fine-mapping and a family-based analysis revealed that rs756853 and the 6-kb distal rs2249817 were the most highly associated single nucleotide polymorphisms. The association finding was replicated in an independent Australian sample, when the analysis was restricted to severely affected cases and unaffected controls (P = 0·026). Analysis of rs2249817 in a combined sample of severely affected German and Australian cases and unaffected controls revealed a strong association signal (P = 9·09 × 10(-8) ). Tissue expression studies demonstrated HDAC9 expression in various tissues, including tissues of relevance to AGA. No strong genotypic effects were observed in genotype-specific expression or splice studies. Pathway analyses supported the hypothesis that HDAC9 plays a functional role in AGA via interaction with the AR gene. CONCLUSIONS: The present study suggests that HDAC9 is the third AGA susceptibility gene.


Assuntos
Alopecia/genética , Cromossomos Humanos Par 7/genética , Histona Desacetilases/genética , Polimorfismo de Nucleotídeo Único/genética , Proteínas Repressoras/genética , Adulto , Processamento Alternativo/genética , Estudos de Casos e Controles , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Masculino
5.
Ned Tijdschr Geneeskd ; 152(15): 880-6, 2008 Apr 12.
Artigo em Holandês | MEDLINE | ID: mdl-18512529

RESUMO

OBJECTIVE: To provide an overview of the morbidity, mortality and survival following the introduction of radiofrequency ablation (RFA) of colorectal liver metastases in the Netherlands. DESIGN: Prospective, descriptive study. METHOD: Between June 1999 and December 2003 in eight hospitals in the Netherlands, 87 patients treated by RFA for colorectal liver metastases were included in the study. The outcome measures were morbidity, 30-day mortality and the percentage local recurrence. RESULTS: In 104 RFA procedures, 199 metastases were ablated; 31 procedures were performed percutaneously and 73 by laparotomy. In 29 procedures, RFA was combined with partial liver resection. The overall postoperative morbidity rate was 19% and the RFA-related morbidity was 14%. 1 patient died following right hemihepatectomy and RFA in the remaining parenchyma (mortality: 1%). Median survival following RFA was 25 months, with a median progression-free survival of 13 months. The overall local recurrence rate was 46%. Since January 2004, this percentage has decreased to approximately 6. Diameter and central location of the metastases were independent risk factors for the development of a local recurrence. CONCLUSION: RFA is an alternative treatment for patients who are not eligible for partial liver resection. The high local recurrence rate in this series reflects the limited experience with this technique during its introduction in the Netherlands. In specialised centres the percentage local recurrence is now 5. Treatment by RFA should always be weighed against the option of partial liver resection and possible (neoadjuvant) chemotherapy. RFA should therefore preferably be carried out in a centre with expertise in the field of liver surgery.


Assuntos
Ablação por Cateter , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/cirurgia , Adulto , Idoso , Neoplasias Colorretais/mortalidade , Feminino , Humanos , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Países Baixos , Estudos Prospectivos , Radiografia Intervencionista , Fatores de Risco , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento
6.
Toxicol In Vitro ; 48: 221-231, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29408669

RESUMO

Harmful effects of diesel emissions can be investigated via exposures of human epithelial cells, but most of previous studies have largely focused on the use of diesel particles or emission sources that are poorly representative of engines used in current traffic. We studied the cellular response of primary bronchial epithelial cells (PBECs) at the air-liquid interface (ALI) to the exposure to whole diesel exhaust (DE) generated by a Euro V bus engine, followed by treatment with UV-inactivated non-typeable Haemophilus influenzae (NTHi) bacteria to mimic microbial exposure. The effect of prolonged exposures was investigated, as well as the difference in the responses of cells from COPD and control donors and the effect of emissions generated during a cold start. HMOX1 and NQO1 expression was transiently induced after DE exposure. DE inhibited the NTHi-induced expression of human beta-defensin-2 (DEFB4A) and of the chaperone HSPA5/BiP. In contrast, expression of the stress-induced PPP1R15A/GADD34 and the chemokine CXCL8 was increased in cells exposed to DE and NTHi. HMOX1 induction was significant in both COPD and controls, while inhibition of DEFB4A expression by DE was significant only in COPD cells. No significant differences were observed when comparing cellular responses to cold engine start and prewarmed engine emissions.


Assuntos
Poluentes Atmosféricos/toxicidade , Brônquios/citologia , Brônquios/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Imunidade Inata/efeitos dos fármacos , Emissões de Veículos/toxicidade , Células Cultivadas , Chaperona BiP do Retículo Endoplasmático , Haemophilus influenzae/imunologia , Humanos , Estresse Oxidativo/efeitos dos fármacos , Material Particulado , Cultura Primária de Células , Doença Pulmonar Obstrutiva Crônica/patologia
7.
J Dent Res ; 96(11): 1314-1321, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28767323

RESUMO

Nonsyndromic cleft palate only (nsCPO) is a facial malformation that has a livebirth prevalence of 1 in 2,500. Research suggests that the etiology of nsCPO is multifactorial, with a clear genetic component. To date, genome-wide association studies have identified only 1 conclusive common variant for nsCPO, that is, a missense variant in the gene grainyhead-like-3 ( GRHL3). Thus, the underlying genetic causes of nsCPO remain largely unknown. The present study aimed at identifying rare variants that might contribute to nsCPO risk, via whole-exome sequencing (WES), in multiply affected Central European nsCPO pedigrees. WES was performed in 2 affected first-degree relatives from each family. Variants shared between both individuals were analyzed for their potential deleterious nature and a low frequency in the general population. Genes carrying promising variants were annotated for 1) reported associations with facial development, 2) multiple occurrence of variants, and 3) expression in mouse embryonic palatal shelves. This strategy resulted in the identification of a set of 26 candidate genes that were resequenced in 132 independent nsCPO cases and 623 independent controls of 2 different ethnicities, using molecular inversion probes. No rare loss-of-function mutation was identified in either WES or resequencing step. However, we identified 2 or more missense variants predicted to be deleterious in each of 3 genes ( ACACB, PTPRS, MIB1) in individuals from independent families. In addition, the analyses identified a novel variant in GRHL3 in 1 patient and a variant in CREBBP in 2 siblings. Both genes underlie different syndromic forms of CPO. A plausible hypothesis is that the apparently nonsyndromic clefts in these 3 patients might represent hypomorphic forms of the respective syndromes. In summary, the present study identified rare variants that might contribute to nsCPO risk and suggests candidate genes for further investigation.


Assuntos
Fissura Palatina/genética , Exoma/genética , Europa (Continente) , Feminino , Predisposição Genética para Doença , Variação Genética , Humanos , Masculino , Análise de Sequência de DNA , Iêmen
8.
J Bone Miner Res ; 9(11): 1697-704, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7863820

RESUMO

Although the osteocyte is the most abundant among the highly differentiated cells of mature bone (osteocytes, lining cells, osteoblasts, and osteoclasts), its properties and functions are the least known and understood. Here we isolated osteocytes from mixed populations of bone cells liberated from fetal chick calvariae by alternate treatments with collagenase and EDTA. The osteocytes were removed from the bone cell populations by binding them via an osteocyte-specific antibody (MAb OB 7.3) to magnetic beads and removing the beads together with the coupled osteocytes from the population using a magnet. Isolated osteocytes were found to be highly differentiated, postmitotic cells that required their typical stellate morphology in culture. Osteocyte populations had alkaline phosphatase (ALP) activity somewhat lower than that of the osteoblast-like cell populations from which they were separated by the immunodissection procedure. On the single-cell level, the ALP activity was highly variable. Parathyroid hormone (PTH) receptors were found to be present on osteocytes as well as on osteoblast-like cells, but not on fibroblast-like cells of the outer periosteum. In response to PTH, osteocytes increased their intracellular levels of cAMP, as did the osteoblast-like cells. Osteocytes appeared to be somewhat more sensitive to PTH than osteoblasts. When seeded onto dentin slices, osteocytes did not corrode the dentin surface to any appraisable degree. We therefore found no evidence to support the notion that osteocytes play a role in the calcium homeostasis through osteocytic osteolysis. Whether osteocytes play an important role in perceiving and transducing hormonal and/or mechanical stimuli remains open for future research.


Assuntos
Osteócitos/citologia , Osteócitos/metabolismo , Fosfatase Alcalina/metabolismo , Animais , Anticorpos Monoclonais , Sítios de Ligação , Diferenciação Celular/fisiologia , Divisão Celular/efeitos dos fármacos , Divisão Celular/fisiologia , Células Cultivadas , Embrião de Galinha , Colagenases/química , AMP Cíclico/metabolismo , Ácido Edético/química , Campos Eletromagnéticos , Fluoresceína-5-Isotiocianato/química , Osteoblastos/metabolismo , Osteócitos/efeitos dos fármacos , Osteócitos/enzimologia , Hormônio Paratireóideo/metabolismo , Hormônio Paratireóideo/farmacologia , Receptores de Hormônios Paratireóideos/metabolismo , Transdução de Sinais/fisiologia , Crânio/citologia , Crânio/embriologia
9.
J Bone Miner Res ; 6(11): 1203-10, 1991 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1839590

RESUMO

We examined the effects of the bisphosphonates Cl2MDP, APD, and Me2APD on osteoclastic resorption in the absence and presence of PTH using fetal mouse osteoclast-free bone explants cocultured with fetal liver as a source of osteoclast precursors. Results revealed qualitative and quantitative differences among the bisphosphonates tested. With Cl2MDP and APD fractional inhibition of resorption (measured as 45Ca release) in the presence of PTH was proportional to that obtained in its absence. In contrast, Me2APD, which is the most potent inhibitor of the three, was found at low concentrations (less than or equal to 5 x 10(-7) M) to enhance the PTH-stimulated osteoclastic resorption. APD as well, at concentrations that could not inhibit resorption, had a similar effect, but Cl2MDP did not. These studies describe a new phenomenon, that low doses of nitrogen-containing bisphosphonates can act synergistically with PTH and enhance osteoclastic resorption. These findings may have clinical implications in the management of patients with increased osteoclastic resorption due to parathyroid overactivity.


Assuntos
Reabsorção Óssea/tratamento farmacológico , Ácido Clodrônico/farmacologia , Difosfonatos/farmacologia , Hormônio Paratireóideo/farmacologia , Animais , Cálcio/análise , Técnicas de Cultura , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Feminino , Camundongos , Camundongos Endogâmicos , Pamidronato , Gravidez
10.
Bone ; 18(4): 305-13, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8726386

RESUMO

Different functions have been proposed for osteocytes over time, but it is now generally accepted that their most important task lies in the sensing of strain caused by mechanical loading on bone. The fact that mechanical strain can be sensed as deformation of the extracellular matrix or as fluid shear stress along the cell, in the space between cell membrane and extracellular matrix, requires that osteocytes have close (specialized) contact with the bone matrix. We studied to which extracellular matrix proteins isolated chicken osteocytes adhere and whether this adhesion is mediated by specific cell adhesion receptors called integrins. The adhesive properties of the osteocytes were compared with that of osteoblasts. Osteocytes (and osteoblasts) adhere to the same substrates (i.e., collagen types I and II, collagen fibers, osteopontin, osteonectin, fibronectin, fibrinogen, thrombospondin, and laminin). Cell spreading varied between substrates, from all cells rounded on thrombospondin to all cells fully spread out on osteopontin, osteonectin, vitronectin, fibronectin, fibrinogen, and laminin. The percentage of osteocytes adhered was equivalent to that of osteoblasts adhered on all substrates except osteopontin and vitronectin, where osteocytes adhered less. The adhesion of osteocytes and osteoblasts to osteopontin, osteonectin, vitronectin, and fibrinogen was strongly inhibited, and to fibronectin and laminin moderately, by an RGD peptide. No RGD inhibition was found on collagen. An antibody against chicken integrin alpha v beta 3, the monoclonal antibody (MAb) 23C6, did not interfere with the adhesion of osteocytes and osteoblasts to matrix proteins, whereas an MAb against chicken integrin subunit beta 1 (CSAT) strongly inhibited adhesion to all substrates. Labeling with osteocyte-specific MAbs (OB7.3, OB37.4, and OB37.11) also did not hinder the adhesion of osteocytes to collagen type I, vitronectin, and osteopontin. Adhesion sites on osteocytes were small compared with the large adhesion plaques of osteoblasts, as demonstrated by interference reflection microscopy and immunocytochemically by staining for vinculin. Osteocyte adhesion is analogous to osteoblast adhesion with regard to the range of extracellular matrix proteins to which they adhere. The adhesion is mediated by the integrin subunit beta 1, but other integrins or nonintegrin adhesion receptors are also involved. Osteocytes make contact with the extracellular matrix via small attachment points which colocalize with vinculin. This connection between the bone matrix and the cytoskeleton may be important for osteocytic sensing of mechanical strain, as it supplies a transduction route of extracellular (mechanical) signals into intracellular messages.


Assuntos
Proteínas da Matriz Extracelular/metabolismo , Matriz Extracelular/metabolismo , Integrinas/metabolismo , Osteócitos/citologia , Animais , Anticorpos Monoclonais/farmacologia , Especificidade de Anticorpos , Adesão Celular/efeitos dos fármacos , Adesão Celular/fisiologia , Moléculas de Adesão Celular/química , Moléculas de Adesão Celular/metabolismo , Células Cultivadas , Embrião de Galinha , Colágeno/química , Colágeno/metabolismo , Meios de Cultivo Condicionados , Fibrinogênio/química , Fibrinogênio/metabolismo , Fibronectinas/química , Fibronectinas/metabolismo , Humanos , Integrinas/imunologia , Laminina/química , Laminina/metabolismo , Glicoproteínas de Membrana/química , Glicoproteínas de Membrana/metabolismo , Oligopeptídeos/farmacologia , Osteoblastos/citologia , Osteoblastos/metabolismo , Osteócitos/efeitos dos fármacos , Osteócitos/metabolismo , Osteonectina/química , Osteonectina/metabolismo , Osteopontina , Receptores Imunológicos/metabolismo , Sialoglicoproteínas/química , Sialoglicoproteínas/metabolismo , Trombospondinas , Vinculina/química
11.
Int J Gynaecol Obstet ; 18(4): 245-7, 1980.
Artigo em Inglês | MEDLINE | ID: mdl-6109665

RESUMO

Since 1977, cul-de-sac insufflation has been used to achieve pneumoperitoneum for laparoscopic sterilization of 570 women. The authors have previously published findings on 350 of these women (Int J Gynaecol Obstet 17(4):375, 1980), reporting technical failure rates of 3.6% and 1.9% for a series of 195 and 155 women, respectively. The failure rate for the latest series of 220 women declined to 1.4%. Reasons for this lower rate and recurring causes of the failures are given, and recommendations for the use of cul-de-sac insufflation for inducing pneumoperitoneum are suggested.


Assuntos
Escavação Retouterina , Pneumoperitônio Artificial/efeitos adversos , Feminino , Humanos , Laparoscopia , Pneumoperitônio Artificial/métodos , Esterilização Tubária
12.
J Dent Res ; 93(4): 376-81, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24563486

RESUMO

Nonsyndromic orofacial clefting (nsOFC) is a common, complex congenital disorder. The most frequent forms are nonsyndromic cleft lip with or without cleft palate (nsCL/P) and nonsyndromic cleft palate only (nsCPO). Although they are generally considered distinct entities, a recent study has implicated a region around the FOXE1 gene in both nsCL/P and nsCPO. To investigate this hypothesis, we analyzed the 2 most strongly associated markers (rs3758249 and rs4460498) in 2 independent samples of differing ethnicities: Central European (949 nsCL/P cases, 155 nsCPO cases, 1163 controls) and Mayan Mesoamerican (156 nsCL/P cases, 10 nsCPO cases, 338 controls). While highly significant associations for both single-nucleotide polymorphisms were obtained in nsCL/P (rs4460498: p Europe = 6.50 × 10(-06), p Mayan = .0151; rs3758249: p Europe = 2.41 × 10(-05), p Mayan = .0299), no association was found in nsCPO (p > .05). Genotyping of rs4460498 in 472 independent European trios revealed significant associations for nsCL/P (p = .016) and nsCPO (p = .043). A meta-analysis of all data revealed a genomewide significant result for nsCL/P (p = 1.31 × 10(-08)), which became more significant when nsCPO cases were added (p nsOFC = 1.56 × 10(-09)). These results strongly support the FOXE1 locus as a risk factor for nsOFC. With the data of the initial study, there is now considerable evidence that this locus is the first conclusive risk factor shared between nsCL/P and nsCPO.


Assuntos
Fenda Labial/genética , Fissura Palatina/genética , Fatores de Transcrição Forkhead/genética , Variação Genética/genética , Estudos de Casos e Controles , Mapeamento Cromossômico , Etnicidade/genética , Feminino , Genes Recessivos/genética , Genótipo , Homozigoto , Humanos , Indígenas Centro-Americanos/genética , Desequilíbrio de Ligação/genética , Masculino , Modelos Genéticos , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , Fatores de Risco , População Branca/genética
13.
Histochem Cell Biol ; 106(5): 495-501, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8950608

RESUMO

Cultures of isolated osteocytes may offer an appropriate system to study osteocyte function, since isolated osteocytes in culture behave very much like osteocytes in vivo. In this paper we studied the capacity of osteocytes to change their surrounding extracellular matrix by production of matrix proteins. With an immunocytochemical method we determined the presence of collagen type I, fibronectin, osteocalcin, osteopontin and osteonectin in cultures of isolated chicken osteocytes, osteoblasts and periosteal fibroblasts. In osteoblast and periosteal fibroblast cultures, large extracellular networks of collagen type I and fibronectin were formed, but in osteocyte populations, extracellular threads of collagen or fibronectin were only rarely found. The percentage of cells positive for osteocalcin, osteonectin and osteopontin in the Golgi apparatus, on the other hand, was highest in the osteocyte population. These results show that osteocytes have the ability to alter the composition of their surrounding extracellular matrix by producing matrix proteins. We suggest this property is of importance for the regulation of the calcification of the bone matrix immediately surrounding the cells. More importantly, as osteocytes depend for their role as mechanosensor cells on their interaction with matrix proteins, the adaptation of the surrounding matrix offers a way to regulate their response to mechanical loading.


Assuntos
Proteínas da Matriz Extracelular/análise , Osteócitos/química , Animais , Adesão Celular , Células Cultivadas , Embrião de Galinha , Colágeno/análise , Citocinas/análise , Fibronectinas/análise , Osteocalcina/análise , Osteonectina/análise , Osteopontina , Fosfoproteínas/análise , Sialoglicoproteínas/análise
14.
Anal Biochem ; 213(2): 426-33, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7694524

RESUMO

In this study we present a rapid, simple, sensitive, inexpensive, and environment-friendly assay for determination of the number of adherent or nonadherent cells cultured in 96-well plates using the supravital stain neutral red. We describe a validation of the method and demonstrate its application to study the effects of hormones (i.e., parathyroid hormone) and cytokines (i.e., tumor necrosis factor-alpha) on the growth of primary cultures of adherent osteoblast-like cells. In addition we show that this method can also be applied to conveniently determine proliferation of cells which grow in suspension, like the CTLL-2 and B-9 cells, which are widely used to measure IL-2 and IL-6 bioactivity, respectively. In these bioassays the changes in optical density induced by IL-2 and IL-6 measured with the neutral red assay are directly comparable with the relative changes measured with the [3H]thymidine incorporation assay. For all types of cells tested, the optical density at 550 nm was directly proportional to the number of cells. The assay, which can be used for different purposes, is an excellent alternative to already existing methods. It is not only easy to perform but also very reproducible, making it ideal for screening of large numbers of samples. Therefore this assay offers a reliable and flexible tool to determine both stimulatory and inhibitory effects of hormones, cytokines, and drugs on cell growth or to study the effects on cell viability.


Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Vermelho Neutro , Coloração e Rotulagem/métodos , Animais , Adesão Celular/fisiologia , Contagem de Células , Divisão Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Humanos , Hibridomas/efeitos dos fármacos , Interleucina-2/farmacologia , Interleucina-6/farmacologia , Camundongos , Vermelho Neutro/farmacocinética , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Hormônio Paratireóideo/farmacologia , Ratos , Reprodutibilidade dos Testes , Fator de Necrose Tumoral alfa/farmacologia
15.
Biochem Biophys Res Commun ; 225(1): 62-8, 1996 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-8769095

RESUMO

It has been postulated that the transduction of mechanical stress signals to bone cells occurs via loading-dependent flow of interstitial fluid through the lacuno-canalicular network of bone. We have shown earlier that chicken osteocytes release enhanced amounts of prostaglandin E2 after 1 h treatment with pulsating fluid flow (PFF, 0.5 +/- 0.02 Pa, 5 Hz). Here we study the acute response to PFF on three cell populations derived from fetal chick calvariae, namely periosteal fibroblasts (PF), an osteoblast and osteocyte containing population (OBmix), and osteocytes (OCY), and the involvement of the actin-cytoskeleton in this process. All three cell populations rapidly (OCY: within 5 min, OBmix, PF: within 10 min) increased their release of prostaglandins E2 and I2 in response to PFF, but the response by OCY was 2-4 times higher than that by OBmix or PF. Disruption of the actin-cytoskeleton by cytochalasin B completely abolished the response. We conclude that osteocytes are more sensitive to fluid shear stress than immature bone cells, and that the actin-cytoskeleton is involved in the response to fluid flow.


Assuntos
Osteócitos/fisiologia , Prostaglandinas/biossíntese , 6-Cetoprostaglandina F1 alfa/biossíntese , Animais , Células Cultivadas , Embrião de Galinha , Meios de Cultura , Técnicas de Cultura/métodos , Dinoprostona/biossíntese , Epoprostenol/biossíntese , Cinética , Osteócitos/citologia , Fluxo Pulsátil , Crânio/citologia , Estresse Mecânico , Fatores de Tempo
16.
Am J Physiol ; 276(1): E171-8, 1999 01.
Artigo em Inglês | MEDLINE | ID: mdl-9886964

RESUMO

To maintain its structural competence, the skeleton adapts to changes in its mechanical environment. Osteocytes are generally considered the bone mechanosensory cells that translate mechanical signals into biochemical, bone metabolism-regulating stimuli necessary for the adaptive process. Prostaglandins are an important part of this mechanobiochemical signaling. We investigated the signal transduction pathways in osteocytes through which mechanical stress generates an acute release of prostaglandin E2 (PGE2). Isolated chicken osteocytes were subjected to 10 min of pulsating fluid flow (PFF; 0.7 +/- 0.03 Pa at 5 Hz), and PGE2 release was measured. Blockers of Ca2+ entry into the cell or Ca2+ release from internal stores markedly inhibited the PFF-induced PGE2 release, as did disruption of the actin cytoskeleton by cytochalasin B. Specific inhibitors of Ca2+-activated phospholipase C, protein kinase C, and phospholipase A2 also decreased PFF-induced PGE2 release. These results are consistent with the hypothesis that PFF raises intracellular Ca2+ by an enhanced entry through mechanosensitive ion channels in combination with Ca2+- and inositol trisphosphate (the product of phospholipase C)-induced Ca2+ release from intracellular stores. Ca2+ and protein kinase C then stimulate phospholipase A2 activity, arachidonic acid production, and ultimately PGE2 release.


Assuntos
Dinoprostona/biossíntese , Osteócitos/metabolismo , Transdução de Sinais/fisiologia , Crânio/embriologia , Actinas/fisiologia , Animais , Ácido Araquidônico/biossíntese , Bloqueadores dos Canais de Cálcio/farmacologia , Separação Celular , Células Cultivadas , Embrião de Galinha/citologia , Embrião de Galinha/metabolismo , Citocalasina B/farmacologia , Citoesqueleto/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Osteócitos/efeitos dos fármacos , Fosfolipases A/antagonistas & inibidores , Fosfolipases A2 , Proteína Quinase C/antagonistas & inibidores , Crânio/citologia , Crânio/metabolismo , Estresse Mecânico , Fosfolipases Tipo C/antagonistas & inibidores
17.
Biochem Biophys Res Commun ; 268(2): 414-9, 2000 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-10679219

RESUMO

Mechanical stress produces flow of fluid in the osteocytic lacunar-canalicular network, which is likely the physiological signal for the adaptive response of bone. We compared the induction of prostaglandin G/H synthase-2 (PGHS-2) by pulsating fluid flow (PFF) and serum in osteocytes, osteoblasts, and periosteal fibroblasts, isolated from 18-day-old fetal chicken calvariae. A serum-deprived mixed population of primarily osteocytes and osteoblasts responded to serum with a two- to threefold induction of PGHS-2 mRNA. Serum stimulated PGHS-2-derived PGE(2) release from osteoblasts and osteocytes but not from periosteal fibroblasts as NS-398, a PGHS-2 blocker, inhibited PGE(2) release from osteocytes and osteoblasts with 65%, but not that from periosteal fibroblasts. On the other hand PFF (0.7 Pa, 5 Hz) stimulated (3 fold) PGHS-2 mRNA only in OCY. The related PGE(2) response could be completely inhibited by NS-398. We conclude that osteocytes have a higher intrinsic sensitivity for loading-derived fluid flow than osteoblasts or periosteal fibroblasts.


Assuntos
Isoenzimas/metabolismo , Osteócitos/enzimologia , Prostaglandina-Endoperóxido Sintases/metabolismo , Fluxo Pulsátil/fisiologia , Animais , Células Cultivadas , Embrião de Galinha , Ciclo-Oxigenase 2 , Ativação Enzimática , Indução Enzimática , Fibroblastos/metabolismo , Isoenzimas/genética , Osteoblastos/metabolismo , Prostaglandina-Endoperóxido Sintases/genética , RNA Mensageiro/metabolismo
18.
Contracept Deliv Syst ; 2(4): 337-42, 1981 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12336996

RESUMO

PIP: This 1978 study of postabortum insertion of multiload copper 250 (ML Cu 250) IUDs involved 382 of 2881 patients who requested 1st or 2nd trimester abortions. 221 were subjected to a 2 year follow-up. In patients 30 years old and younger expulsions occurred at 2 weeks, 4 weeks, and 6 months. The accidental pregnancy rate was 0.9%, the expulsion rate was 1.3%, the removal rate due to bleeding was 9.5% and from infection (5.4%), the continuation rate was 80%. The bleeding and infection rates after 6 months (9.9%), 12 months (13.5%), and 2 years (14.9%) were higher than previous studies. The immediate postabortum ML Cu 250 insertion appears to be a safe and acceptable method of contraception. Menstrual and intermenstrual bleeding in women after postabortum ML Cu 250 insertion is significantly higher than after interim and postpartum insertion, but similar to that after interim Nova T insertion. Factors involved in the vaginal bleeding may be: 1) decreased fibrinolytic activity of the endometrium, 2) production of plasminogen-activator inhibitors by the decidua, or 3) increased myometrial contractility due to extra prostaglandin synthesis caused by copper IUDs.^ieng


Assuntos
Assistência ao Convalescente , Seguimentos , Dispositivos Intrauterinos , Retenção Psicológica , Sangue , Anticoncepção , Diagnóstico , Serviços de Planejamento Familiar , Fibrinólise , Hemorragia , Infecções , Prostaglandinas , Reprodução , Pesquisa
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