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1.
ESMO Open ; 9(1): 102202, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38118368

RESUMO

BACKGROUND: The phase III RATIONALE-302 study evaluated tislelizumab, an anti-programmed cell death protein 1 antibody, as second-line (2L) treatment for advanced/metastatic esophageal squamous cell carcinoma (ESCC). This prespecified exploratory analysis investigated outcomes in patients from Europe and North America (Europe/North America subgroup). PATIENTS AND METHODS: Patients with tumor progression during/after first-line systemic treatment were randomized 1 : 1 to open-label tislelizumab or investigator's choice of chemotherapy (paclitaxel, docetaxel, or irinotecan). RESULTS: The Europe/North America subgroup comprised 108 patients (tislelizumab: n = 55; chemotherapy: n = 53). Overall survival (OS) was prolonged with tislelizumab versus chemotherapy (median: 11.2 versus 6.3 months), with a hazard ratio (HR) of 0.55 [95% confidence interval (CI) 0.35-0.87]; HR was similar irrespective of programmed death-ligand 1 score [≥10%: 0.47 (95% CI 0.18-1.21); <10%: 0.55 (95% CI 0.30-1.01)]. Median progression-free survival was 2.3 versus 2.7 months with tislelizumab versus chemotherapy [HR: 0.97 (95% CI 0.64-1.47)]. Overall response rate was greater with tislelizumab (20.0%) versus chemotherapy (11.3%), with more durable response (median duration of response: 5.1 versus 2.1 months). Tislelizumab had a favorable safety profile versus chemotherapy, with fewer patients experiencing ≥grade 3 treatment-related adverse events (13.0% versus 51.0%). Those on tislelizumab experienced less deterioration in health-related quality of life, physical functioning, and/or disease- and treatment-related symptoms (i.e. fatigue, pain, and eating problems) as compared to those on chemotherapy, per the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 (QLQ-C30) and QLQ-OES18 scores. CONCLUSIONS: As a 2L therapy for advanced/metastatic ESCC, tislelizumab improved OS and had a favorable safety profile as compared to chemotherapy in European/North American ESCC patients in the randomized phase III RATIONALE-302 study.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/patologia , Qualidade de Vida , Anticorpos Monoclonais Humanizados/farmacologia , Anticorpos Monoclonais Humanizados/uso terapêutico
3.
ESMO Open ; 7(4): 100517, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35785595

RESUMO

BACKGROUND: RATIONALE 302 (NCT03430843) an open-label, phase III study of second-line treatment of advanced/metastatic esophageal squamous cell carcinoma (ESCC), reported that tislelizumab, relative to investigator-chosen chemotherapy (ICC), was associated with improvements in overall survival and a favorable safety profile. This study assessed the health-related quality of life (HRQoL) and ESCC-related symptoms of patients in RATIONALE 302. METHODS: Adults with advanced/metastatic ESCC whose disease progressed following prior systemic therapy were randomized 1 : 1 to receive either tislelizumab or ICC (paclitaxel, docetaxel, or irinotecan). HRQoL was measured using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 items (EORTC QLQ-C30), the EORTC Quality of Life Questionnaire Oesophageal Cancer Module 18 items (QLQ-OES18), and the EuroQoL Five-Dimensions Five-Levels (EQ-5D-5L) visual analogue scale. Mixed effect modeling for repeated measurements examined changes from baseline to weeks 12 and 18. The Kaplan-Meier method was used to examine time to deterioration. RESULTS: Overall, 512 patients were randomized to tislelizumab (n = 256) or ICC (n = 256). The tislelizumab arm maintained QLQ-C30 global health status/quality whereas the ICC arm worsened at week 12 {difference in least square (LS) mean change: 5.8 [95% confidence interval (CI): 2.0-9.5], P = 0.0028} and week 18 [difference in LS mean change: 8.1 (95% CI: 3.4-12.8), P = 0.0008]. Physical functioning (week 18) and fatigue (weeks 12 and 18) worsened less in the tislelizumab compared with the ICC arm. The tislelizumab arm improved in reflux symptoms, whereas the ICC worsened at week 12 [difference in LS mean change: -4.1 (95% CI: -7.6 to -0.6), P = 0.0229]. The visual analogue scale remained consistent in the tislelizumab arm whereas it worsened in the ICC arm. The hazard of time to deterioration was lower in tislelizumab patients compared with ICC for physical functioning and reflux. CONCLUSIONS: HRQoL, including fatigue symptoms and physical functioning, was maintained in patients with advanced or metastatic ESCC receiving tislelizumab compared with ICC-treated patients. These results provide additional support for the benefits of tislelizumab in this patient population.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Adulto , Anticorpos Monoclonais Humanizados , Fadiga , Humanos , Qualidade de Vida
4.
Cancer Treat Res Commun ; 30: 100501, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34952253

RESUMO

BACKGROUND: This study assessed the effects of adding tislelizumab to first-line standard-of- care chemotherapy on the health-related quality of life (HRQoL) of patients with advanced squamous non-small cell lung cancer (sq-NSCLC). PATIENTS AND METHODS: Patients in this open-label, multicenter, phase 3 RATIONALE 307 trial were randomized to one of the three arms: tislelizumab plus carboplatin and paclitaxel (Arm A), tislelizumab plus carboplatin and nab-paclitaxel (Arm B), or paclitaxel plus carboplatin (Arm C). HRQoL was measured using the European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire Core 30 (QLQ-C30) and the EORTC Quality of Life Questionnaire Lung Cancer 13-item module (QLQ-LC13). Mean score change from baseline at Weeks 6 and 12 in the QLQ-C30's global health status/quality of life (GHS/QoL), fatigue, and physical functioning scores and QLQ-LC13 lung cancer specific subscales were examined. Time to deterioration was estimated for the GHS/QoL score. RESULTS: A total of 355 sq-NSCLC patients received at least one dose of study drug and completed at least one HRQoL assessment. The GHS/QoL scores improved in Arms A and B relative to Arm C at Weeks 6 and 12. Arms A and B also experienced a reduction in most lung cancer-specific symptoms relative to Arm C. Time to deterioration of GHS/QoL was not reached by any of the three arms. CONCLUSIONS: The addition of tislelizumab to platinum-based chemotherapy is associated with improvements in sq-NSCLC patients' HRQoL, especially in GHS/QoL and most importantly in lung cancer-specific symptoms including coughing, dyspnea, and hemoptysis.

5.
J Med Eng Technol ; 43(5): 323-333, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31578101

RESUMO

Between-individual variability of body temperature has been little investigated, but is of clinical importance: for example, in detection of neutropenic sepsis during chemotherapy. We studied within-person and between-person variability in temperature in healthy adults and those receiving chemotherapy using a prospective observational design involving 29 healthy participants and 23 patients undergoing chemotherapy. Primary outcome was oral temperature. We calculated each patient's mean temperature, standard deviation within each patient (within-person variability), and between patients (between-person variability). Secondary analysis explored temperature changes in the three days before admission for neutropenic sepsis. 1,755 temperature readings were returned by healthy participants and 1,765 by chemotherapy patients. Mean participant temperature was 36.16 C (95% CI 36.07-36.26) in healthy participants and 36.32 C (95% CI 36.18-36.46) in chemotherapy patients. Healthy participant within-person variability was 0.40 C (95% CI 0.36-0.44) and between-person variability was 0.26 C (95% CI 0.16-0.35). Chemotherapy patient within-person variability was 0.39 C (95% CI 0.34-0.44) and between-person variability was 0.34 C (95% CI 0.26-0.48). Thus, use of a population mean rather than personalised baselines is probably sufficient for most clinical purposes as between-person variability is not large compared to within-person variability. Standardised guidance and provision of thermometers to patients might help to improve recording and guide management.


Assuntos
Antineoplásicos/uso terapêutico , Temperatura Corporal , Neoplasias/tratamento farmacológico , Adolescente , Adulto , Idoso , Variação Biológica Individual , Variação Biológica da População , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/fisiopatologia , Neutropenia/induzido quimicamente , Neutropenia/fisiopatologia , Adulto Jovem
7.
Int J Tuberc Lung Dis ; 14(2): 203-9, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20074412

RESUMO

SETTING: Central Rio de Janeiro, Brazil. OBJECTIVE: To compare the impact of routine DOTS vs. enhanced DOTS (DOTS-Ampliado or DOTS-A) on tuberculosis (TB) incidence. DESIGN: Cluster-randomized trial in eight urban neighborhoods pair-matched by TB incidence and randomly assigned to receive either the DOTS-A or DOTS strategy. DOTS-A added intensive screening of household contacts of active TB cases and provision of treatment to secondary cases and preventive therapy to contacts with latent TB infection (LTBI) to the standard DOTS strategy. The primary endpoint was the TB incidence rates in communities after 5 years of intervention. RESULTS: From November 2000 to December 2004, respectively 339 and 311 pulmonary TB cases were enrolled and 1003 and 960 household were identified in DOTS and DOTS-A communities. Among contacts from DOTS-A communities, 26 (4%) had active TB diagnosed and treated, 429 (61.3%) had LTBI detected and 258 (60.1%) started preventive therapy. TB incidence increased by 5% in DOTS communities and decreased by 10% in DOTS-A communities, for a difference of 15% after 5 years (P = 0.04). CONCLUSION: DOTS-A was associated with a modest reduction in TB incidence and may be an important strategy for reducing the burden of TB.


Assuntos
Antituberculosos/administração & dosagem , Terapia Diretamente Observada/métodos , Tuberculose/prevenção & controle , Adulto , Antituberculosos/uso terapêutico , Brasil/epidemiologia , Busca de Comunicante , Características da Família , Feminino , Seguimentos , Humanos , Incidência , Masculino , Programas de Rastreamento/métodos , Tuberculose/epidemiologia , População Urbana
8.
Cancer Metastasis Rev ; 25(4): 589-600, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17165130

RESUMO

The three mammalian Runt homology domain transcription factors (Runx1, Runx2, Runx3) support biological control by functioning as master regulatory genes for the differentiation of distinct tissues. Runx proteins also function as cell context-dependent tumor suppressors or oncogenes. Abnormalities in Runx mediated gene expression are linked to cell transformation and tumor progression. Runx2 is expressed in mesenchymal linage cells committed to the osteoblast phenotype and is essential for bone formation. This skeletal transcription factor is aberrantly expressed at high levels in breast and prostate tumors and cells that aggressively metastasize to the bone environment. In cancer cells, Runx2 activates expression of bone matrix and adhesion proteins, matrix metalloproteinases and angiogenic factors that have long been associated with metastasis. In addition, Runx2 mediates the responses of cells to signaling pathways hyperactive in tumors, including BMP/TGFbeta and other growth factor signals. Runx2 forms co-regulatory complexes with Smads and other co-activator and co-repressor proteins that are organized in subnuclear domains to regulate gene transcription. These activities of Runx2 contribute to tumor growth in bone and the accompanying osteolytic disease, established by interfering with Runx2 functions in metastatic breast cancer cells. Inhibition of Runx2 in MDA-MB-231 cells transplanted to bone decreased tumorigenesis and prevented osteolysis. This review evaluates evidence that Runx2 regulates early metastatic events in breast and prostate cancers, tumor growth, and osteolytic bone disease. Consideration is given to the potential for inhibition of this transcription factor as a therapeutic strategy upstream of the regulatory events contributing to the complexity of metastasis to bone.


Assuntos
Osso e Ossos/metabolismo , Osso e Ossos/patologia , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias/metabolismo , Neoplasias/patologia , Animais , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Humanos , Metástase Neoplásica , Neoplasias/genética , Osteólise/metabolismo , Osteólise/patologia
9.
Clin Biochem ; 39(4): 378-86, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16545357

RESUMO

OBJECTIVES: This study evaluated the analytical characteristics of the new Abbott microparticle enzyme immunoassay (MEIA) for sirolimus. DESIGN AND METHODS: The protocol consisted of nine sections: evaluation of antibody specificity, linearity, detection limit, quantification limit, endogenous interferents, exogenous interferents, precision, proficiency testing panel, and method comparison. RESULTS: The mean analytical detection limit was 0.68 microg/L. The sirolimus concentration corresponding to a total CV of 20% was 1.5 microg/L. Linearity of response was demonstrated across the dynamic range of the assay. Total precision (CVs) at QC control levels from 5 to 22 microg/L ranged from 5.7 to 12.6%. Assay standardization was found to be in good agreement with LC/MS/MS as compared with target values for spiked sirolimus proficiency samples from an international sirolimus proficiency testing program. Good correlations (R values) of the immunoassay were observed in comparisons to LC/MS/MS. R values tended to be lower in comparisons with LC/UV methods. Across both LC-based methods and all study sites, there was approximately 25% overall positive slope bias due to cross reactivity of the MEIA antibody to metabolites of sirolimus. The assay cross-reactivity to metabolites of sirolimus parent drug ranged from 6 to 63%. Assay interferences were minimal with the exception of hematocrit, which presented a negative relationship to measured sirolimus concentration. CONCLUSIONS: The MEIA demonstrated acceptable analytical characteristics for use for routine monitoring of sirolimus immunosuppressive therapy, and is a viable alternative to HPLC-based methods for sirolimus monitoring.


Assuntos
Técnicas Imunoenzimáticas/métodos , Imunossupressores/sangue , Sirolimo/sangue , Calibragem , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrofotometria Ultravioleta , Espectrometria de Massas em Tandem
10.
J Chem Phys ; 123(21): 214705, 2005 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-16356059

RESUMO

Grazing incidence x-ray-diffraction investigations of the structures of Langmuir-Blodgett films of cadmium behenate with 1, 2, 3, 5, and 21 monolayers are reported. The single monolayer film, deposited on a hydrophilic substrate, showed a hexagonal structure, whereas the bilayer film, deposited on a hydrophobic substrate, had a rectangular structure with herringbone orientation of the acyl chains. With multilayer films formed on a hydrophilic substrate, it was possible to detect that the hexagonal structure of the first layer was retained when additional layers were deposited and that the additional layers had the same rectangular structure as the bilayer.


Assuntos
Ácidos Graxos/química , Interações Hidrofóbicas e Hidrofílicas , Bicamadas Lipídicas , Estrutura Molecular , Difração de Raios X
11.
Bone ; 36(2): 300-10, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15780956

RESUMO

Recent studies from our laboratory demonstrate that TNF-alpha signaling contributes to the regulation of chondrocyte apoptosis and a lack of TNF-alpha signaling leads to a persistence of cartilaginous callus and delayed resorption of mineralized cartilage. This study examines how delays in the endochondral repair process affect the expression of specific mediators of proteolytic cartilage turnover and vascularization. Simple closed fractures were produced in wild type and TNF-alpha receptor (p55-/-/p75-/-)-deficient mice. Using ribonuclease protection assay (RPA) and microarray analysis, the expression of multiple mRNAs for various angiogenic factors and the metalloproteinase gene family were measured in fracture calluses. The direct actions of TNFalpha on the expression of specific angiogenic factors and metalloproteinases (MMPs) was examined in both cultured callus cells and articular chondrocytes to compare the effects of TNF-alpha in growth cartilage versus articular cartilage. MMPs 2, 9, 13, and 14 were quantitatively the most prevalent metalloproteases and all showed peaks in expression during the chondrogenic period. In the absence of TNF-alpha signaling, the expression of all of these mRNAs was reduced. The angiopoietin families of vascular regulators and their receptors were expressed at much higher levels than the VEGFs and their receptors and while the angiopoietins showed diminished or delayed expression in the absence of TNF-alpha signaling, VEGF and its receptors remained unaltered. The expression of vascular endothelial growth inhibitor (VEGI or TNFSF15) showed a near absence in its expression in the TNF-alpha receptor-deficient mice. In vitro assessment of cultured fracture callus cells in comparison to primary articular chondrocytes showed that TNF-alpha treatment specifically induced the expression of MMP9, MMP14, VEGI, and Angiopoietin 2. These results suggest that TNF-alpha signaling in chondrocytes controls vascularization of cartilage through the regulation of angiopoietin and VEGI factors which play counterbalancing roles in the induction of growth arrest, or apoptosis in endothelial cells. Furthermore, TNF-alpha appears to regulate, in part, the expression of two key proteolytic enzymes, MMP 9 and MMP14 that are known to be crucial to the progression of vascularization and turnover of mineralized cartilage. Thus, TNF-alpha signaling in healing fractures appears to coordinate the expression of specific regulators of endothelial cell survival and metalloproteolytic enzymes and is essential in the transition and progression of the endochondral phase of fracture repair.


Assuntos
Proteínas Angiogênicas/biossíntese , Condrócitos/fisiologia , Consolidação da Fratura/fisiologia , Metaloproteinases da Matriz/biossíntese , Transdução de Sinais/fisiologia , Fator de Necrose Tumoral alfa/deficiência , Fator de Necrose Tumoral alfa/fisiologia , Proteínas Angiogênicas/metabolismo , Animais , Sobrevivência Celular/fisiologia , Condrócitos/citologia , Condrócitos/metabolismo , Consolidação da Fratura/genética , Regulação da Expressão Gênica/fisiologia , Masculino , Metaloproteinases da Matriz/genética , Metaloproteinases da Matriz/fisiologia , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Fator de Necrose Tumoral alfa/genética
12.
Int J Surg ; 3(3): 206-12, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-17462285

RESUMO

Gastrointestinal stromal tumours (GISTs) are defined as a group of C-KIT positive mesenchymal tumours of the gastrointestinal tract. Although they may arise throughout the gut, the commonest sites are stomach and small intestine. Over 80% of metastases are to the liver and omentum. Targeted therapy (imatinib) can inhibit C-KIT and thereby aberrant tumoural proliferation. Imatinib may induce shrinkage of lesions and cystic change. Such physical changes often correspond with reduced metabolic activity demonstrated by (18-FDG)PET scans. These changes may enable metastatectomy reducing tumour pain and the risk of haemorrhage and rupture in the short term. In the long term, resection may lessen the risk of recurrence by removing potentially resistant clones. The precise role of palliative resection for GIST metastases on imatinib remains unclear. Imatinib has changed the natural history of metastatic GISTs, with increased survival times. Surgery remains an important management strategy in the metastatic setting because complete pathological responses are rare with imatinib. Surgery is likely to provide the best palliation, greatest reduction in tumour burden and eliminate resistant clones. A multidisciplinary team approach with expertise concentrated in a few centres specialising in the management of these rare tumours is vital to the successful outcome. Future issues regarding the management of differential response of the metastases to imatinib are highlighted. With the emergence of techniques enabling identification of the precise mutational status of the C-KIT oncogene, the imatinib/surgery sequence could be tailored to the type of C-KIT mutation.

13.
J Bone Miner Res ; 18(9): 1584-92, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12968667

RESUMO

UNLABELLED: TNF-alpha is a major inflammatory factor that is induced in response to injury, and it contributes to the normal regulatory processes of bone resorption. The role of TNF-alpha during fracture healing was examined in wild-type and TNF-alpha receptor (p55(-/-)/p75(-/-))-deficient mice. The results show that TNF-alpha plays an important regulatory role in postnatal endochondral bone formation. INTRODUCTION: TNF-alpha is a major inflammatory factor that is induced as part of the innate immune response to injury, and it contributes to the normal regulatory processes of bone resorption. METHODS: The role of TNF-alpha was examined in a model of simple closed fracture repair in wild-type and TNF-alpha receptor (p55(-/-)/p75(-/-))-deficient mice. Histomorphometric measurements of the cartilage and bone and apoptotic cell counts in hypertrophic cartilage were carried out at multiple time points over 28 days of fracture healing (n = 5 animals per time point). The expression of multiple mRNAs for various cellular functions including extracellular matrix formation, bone resorption, and apoptosis were assessed (triplicate polls of mRNAs). RESULTS AND CONCLUSIONS: In the absence of TNF-alpha signaling, chondrogenic differentiation was delayed by 2-4 days but subsequently proceeded at an elevated rate. Endochondral tissue resorption was delayed 2-3 weeks in the TNF-alpha receptor (p55(-/-)/p75(-/-))-deficient mice compared with the wild-type animals. Functional studies of the mechanisms underlying the delay in endochondral resorption indicated that TNF-alpha mediated both chondrocyte apoptosis and the expression of proresorptive cytokines that control endochondral tissue remodeling by osteoclasts. While the TNF-alpha receptor ablated animals show no overt developmental alterations of their skeletons, the results illustrate the primary roles that TNF-alpha function contributes to in promoting postnatal fracture repair as well as suggest that processes of skeletal tissue development and postnatal repair are controlled in part by differing mechanisms. In summary, these results show that TNF-alpha participates at several functional levels, including the recruitment of mesenchymal stem, apoptosis of hypertrophic chondrocytes, and the recruitment of osteoclasts function during the postnatal endochondral repair of fracture healing.


Assuntos
Cartilagem/fisiologia , Consolidação da Fratura/fisiologia , Fator de Necrose Tumoral alfa/fisiologia , Animais , Antígenos CD/genética , Antígenos CD/fisiologia , Apoptose , Sequência de Bases , Reabsorção Óssea/genética , Reabsorção Óssea/patologia , Reabsorção Óssea/fisiopatologia , Cartilagem/fisiopatologia , Condrócitos/patologia , Condrócitos/fisiologia , Masculino , Camundongos , Camundongos Knockout , Camundongos Transgênicos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores do Fator de Necrose Tumoral/deficiência , Receptores do Fator de Necrose Tumoral/genética , Receptores do Fator de Necrose Tumoral/fisiologia , Receptores Tipo I de Fatores de Necrose Tumoral , Receptores Tipo II do Fator de Necrose Tumoral , Transdução de Sinais , Fator de Necrose Tumoral alfa/deficiência , Fator de Necrose Tumoral alfa/genética
14.
J Paediatr Child Health ; 39(7): 516-7, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12969205

RESUMO

OBJECTIVE: To determine whether the cystic fibrosis (CF) delta-F508 gene mutation predisposes to intussusception, and so selects infants who should not receive rotavirus vaccine. METHODS: Stored neonatal screening blood spots, retrieved from 81 infants with intussusception and from 79 controls, were tested for the presence of the CF delta-F508 gene mutation. RESULTS: Prevalence of the mutation was similar in blood specimens from intussusception patients and from controls. CONCLUSION: Testing for the CF delta-F508 mutation at birth is unlikely to identify infants predisposed to intussusception, and therefore is not relevant to rotavirus vaccine programs.


Assuntos
Fibrose Cística/genética , Intussuscepção/etiologia , Triagem Neonatal , Vacinas contra Rotavirus/administração & dosagem , Austrália , Fibrose Cística/sangue , Triagem de Portadores Genéticos , Humanos , Recém-Nascido , Intussuscepção/sangue , Mutação , Razão de Chances
15.
Connect Tissue Res ; 44 Suppl 1: 85-91, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12952179

RESUMO

Cartilage formation always precedes that of bone during endochondral skeletal development. To determine if chondrocytes provide inductive signals for osteogenesis, C3H10T(1/2) mesenchymal stem cells were co-cultured in membrane separated transwell culture chambers with chondrocytes, osteoblasts, or fibroblasts. Osteogenesis, as assessed by the expression of osteocalcin mRNAs, was strongly induced in the C3H10T(1/2) cells co-cultured with chondrocytes but not induced by co-culture with either osteoblasts or fibroblasts. Interestingly, while only osteogenic differentiation was observed in the C3H10T(1/2) cells co-cultured with chondrocytes, bone morphogenetic protein (BMP)-7 treatment induced an ordered endochondral progression of skeletal cell differentiation in which chondrogenic differentiation preceded osteogenesis by 2 to 4 days. A nutrient enriched growth environment enhanced osteogenic differentiation induced by either co-culture or BMP-7 treatment 2- to 5-fold. Nutrient enhanced osteogenic differentiation was associated with an activation of the retinoblastoma-mediated signal transduction pathways. In summary, these results show that osteogenesis is selectively induced by morphogenetic signals produced by chondrocytes and that a nutrient rich environment enhances both BMP-7- and co-culture-induced osteogenic differentiation.


Assuntos
Proteínas Morfogenéticas Ósseas/metabolismo , Condrócitos/metabolismo , Meios de Cultura/metabolismo , Osteogênese/fisiologia , Fator de Crescimento Transformador beta , Animais , Proteína Morfogenética Óssea 7 , Proteínas Morfogenéticas Ósseas/farmacologia , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Embrião de Galinha , Condrócitos/citologia , Condrócitos/efeitos dos fármacos , Técnicas de Cocultura , Expressão Gênica/efeitos dos fármacos , Mesoderma/citologia , Camundongos , Camundongos Endogâmicos C3H , Análise de Sequência com Séries de Oligonucleotídeos , Osteocalcina/biossíntese , Osteocalcina/genética , Osteogênese/efeitos dos fármacos , RNA Mensageiro/metabolismo , Transdução de Sinais , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo
16.
Neurology ; 59(12): 1994-7, 2002 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-12499502

RESUMO

Graft-vs-host disease (GVHD) is a potentially treatable cause of progressive neurologic decline after bone marrow transplantation (BMT). The authors present histologic confirmation of CNS granulomatous angiitis in a child with chronic GVHD after BMT. Since cranial MRI showed only nonspecific findings, CNS vasculitis associated with GVHD after BMT may be underdiagnosed.


Assuntos
Transtornos Cerebrovasculares/etiologia , Doença Enxerto-Hospedeiro/complicações , Vasculite/etiologia , Adolescente , Corticosteroides/uso terapêutico , Transplante de Medula Óssea/efeitos adversos , Encéfalo/patologia , Transtornos Cerebrovasculares/tratamento farmacológico , Transtornos Cerebrovasculares/patologia , Feminino , Doença Enxerto-Hospedeiro/patologia , Humanos , Leucemia Mieloide Aguda/cirurgia , Vasculite/tratamento farmacológico , Vasculite/patologia
17.
Otol Neurotol ; 22(6): 931-7, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11698822

RESUMO

AIMS: This study investigated the development of the fallopian canal with particular reference to the mode of ossification and dehiscences, sites of incomplete closure around the facial nerve. BACKGROUND: The precise sequence of events surrounding ossification of the tissues around the facial nerve is uncertain. Incomplete ossification results in dehiscence of the adult structure, which places the nerve at increased risk of damage from disease processes in the middle ear and iatrogenic trauma during otologic surgery. METHODS: Twenty-four temporal bones from 12-to 36-week human fetuses were resected. Eight temporal bones from 22-to 36-week fetuses were microsliced to produce 1.5-mm horizontal sections and radiographed. Sixteen temporal bones from 12-to 35-week fetuses were serially microtomed to produce 7-microm slices, which were stained with hematoxylin and eosin. Quantitative and qualitative analyses of these sections were performed to document patterns of closure of the primitive canal and dehiscence formation. RESULTS: The tympanic part of the primitive fallopian canal, the facial sulcus, developed anteroposteriorly from the geniculate fossa to enclose the facial nerve. The mesenchyme that formed the facial sulcus underwent endochondral ossification, while the bone which capped or closed the sulcus developed in membrane. In the tympanic segment, permanent congenital dehiscences were elliptical and about 1 mm in length. CONCLUSIONS: This study clarifies the mode of development of the fallopian canal, with particular reference to dehiscences, and provides a scientific basis for otologic practice.


Assuntos
Nervo Facial , Nervo Facial/citologia , Nervo Facial/diagnóstico por imagem , Nervo Facial/embriologia , Humanos , Radiografia , Osso Temporal/citologia , Osso Temporal/diagnóstico por imagem , Osso Temporal/embriologia
18.
Mol Cell Biol ; 21(8): 2891-905, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11283267

RESUMO

Expression of the bone sialoprotein (BSP) gene, a marker of bone formation, is largely restricted to cells in mineralized tissues. Recent studies have shown that the Cbfa1 (also known as Runx2, AML-3, and PEBP2alphaA) transcription factor supports commitment and differentiation of progenitor cells to hypertrophic chondrocytes and osteoblasts. This study addresses the functional involvement of Cbfa sites in expression of the Gallus BSP gene. Gel mobility shift analyses with nuclear extracts from ROS 17/2.8 osteoblastic cells revealed that multiple Cbfa consensus sequences are functional Cbfa DNA binding sites. Responsiveness of the 1.2-kb Gallus BSP promoter to Cbfa factors Cbfa1, Cbfa2, and Cbfa3 was assayed in osseous and nonosseous cells. Each of the Cbfa factors mediated repression of the wild-type BSP promoter, in contrast to their well known activation of various hematopoietic and skeletal phenotypic genes. Suppression of BSP by Cbfa factors was not observed in BSP promoters in which Cbfa sites were deleted or mutated. Expression of the endogenous BSP gene in Gallus osteoblasts was similarly downregulated by forced expression of Cbfa factors. Our data indicate that Cbfa repression of the BSP promoter does not involve the transducin-like enhancer (TLE) proteins. Neither coexpression of TLE1 or TLE2 nor the absence of the TLE interaction motif of Cbfa1 (amino acids 501 to 513) influenced repressor activity. However, removal of the C terminus of Cbfa1 (amino acids 362 to 513) relieved suppression of the BSP promoter. Our results, together with the evolutionary conservation of the seven Cbfa sites in the Gallus and human BSP promoters, suggest that suppressor activity by Cbfa is of significant physiologic consequence and may contribute to spatiotemporal expression of BSP during bone development.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Proteínas de Neoplasias , Regiões Promotoras Genéticas , Proteínas de Protozoários , Sialoglicoproteínas/genética , Fatores de Transcrição/metabolismo , Animais , Sequência de Bases , Sítios de Ligação/genética , Linhagem Celular , Embrião de Galinha , Subunidade alfa 1 de Fator de Ligação ao Core , Subunidades alfa de Fatores de Ligação ao Core , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Humanos , Sialoproteína de Ligação à Integrina , Mutagênese Sítio-Dirigida , Ratos , Proteínas Repressoras/metabolismo
19.
Addict Behav ; 26(1): 63-78, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11196293

RESUMO

Concurrent use of alcohol and cigarettes among adolescents is a serious public health issue. Trends in concurrent use of alcohol and cigarettes were determined using data from three comparable large statewide samples of 7-12th-grade students in New York State, from surveys conducted in 1983, 1990, and 1994. The prevalence of use of alcohol and cigarettes decreased from 1983 (23%) to 1990 (19%), and increased by 1994 (22%). Logistic regression analysis showed that these trends are highly significant, and that the probability of use of alcohol and cigarettes is higher for females than males, increases with age, and is lower for most ethnic minorities than for Whites. In the 1990s, Blacks, Hispanics, and Asians increased in their probability of concurrent use more than did Whites. Users of both alcohol and cigarettes are at increased risk of personal and social problems, as well as increased risk of delinquency. Drinking and smoking show synergistic effects on illicit drug use and drug problems.


Assuntos
Comportamento do Adolescente , Consumo de Bebidas Alcoólicas/psicologia , Fumar/psicologia , Adolescente , Criança , Etnicidade , Feminino , Inquéritos Epidemiológicos , Humanos , Delinquência Juvenil , Masculino , Fatores Sexuais
20.
J Cell Biol ; 155(7): 1137-45, 2001 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-11756468

RESUMO

Dam1p, Duo1p, and Dad1p can associate with each other physically and are required for both spindle integrity and kinetochore function in budding yeast. Here, we present our purification from yeast extracts of an approximately 245 kD complex containing Dam1p, Duo1p, and Dad1p and Spc19p, Spc34p, and the previously uncharacterized proteins Dad2p and Ask1p. This Dam1p complex appears to be regulated through the phosphorylation of multiple subunits with at least one phosphorylation event changing during the cell cycle. We also find that purified Dam1p complex binds directly to microtubules in vitro with an affinity of approximately 0.5 microM. To demonstrate that subunits of the Dam1p complex are functionally important for mitosis in vivo, we localized Spc19-green fluorescent protein (GFP), Spc34-GFP, Dad2-GFP, and Ask1-GFP to the mitotic spindle and to kinetochores and generated temperature-sensitive mutants of DAD2 and ASK1. These and other analyses implicate the four newly identified subunits and the Dam1p complex as a whole in outer kinetochore function where they are well positioned to facilitate the association of chromosomes with spindle microtubules.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Proteínas Fúngicas/fisiologia , Cinetocoros/fisiologia , Proteínas de Neoplasias/metabolismo , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Antígenos de Neoplasias , Proteínas do Citoesqueleto , Imunofluorescência , Genótipo , Proteínas de Fluorescência Verde , Cinetocoros/ultraestrutura , Proteínas Luminescentes/análise , Substâncias Macromoleculares , Espectrometria de Massas , Microtúbulos/metabolismo , Complexos Multiproteicos , Mutação , Proteínas de Neoplasias/fisiologia , Fosforilação , Ligação Proteica , Saccharomyces cerevisiae/fisiologia , Saccharomyces cerevisiae/ultraestrutura , Fuso Acromático/ultraestrutura
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