Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 73
Filtrar
1.
J Appl Microbiol ; 129(3): 612-625, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32274883

RESUMO

AIMS: Identification of the mycobiota associated to the marine echinoderm Holothuria poli and investigation of cytotoxic and pro-osteogenic potential of isolated strains. METHODS AND RESULTS: Fungal strains were isolated from the animal's body-wall, intestine and faeces. The species identification was based on DNA barcoding and morphophysiological observations. Forty-seven species were identified, all are Ascomycota and mainly belonging to Aspergillus and Penicillium genera. Sixteen strains were grown on three media for chemical extraction. Cytotoxic activity was tested on a hepatic cancer cell line (HepG2), the cells viability was evaluated after treatment using a resazurin based assay (AlamarBlue). Pro-osteogenic activity was tested on human Mesenchymal stem cell, differentiation was measured as the alkaline phosphatase production through reaction with p-nitrophenylphosphate or as the cells ability to mineralize calcium using a colorimetric kit (StanBio). Cytotoxic activity was recorded for four fungal species while five of 48 extracts highlighted bioactivity towards human mesenchymal stem cells. CONCLUSIONS: The presence of relevant animal-associated mycobiota was observed in H. poli and selected strains showed cytotoxic potential and pro-osteogenic activity. SIGNIFICANCE AND IMPACT OF THE STUDY: Our work represents the first report of a Mediterranean Sea cucumber mycobiota and highlights the isolates potential to synthetize compounds of pharmaceutical interest for regenerative medicine.


Assuntos
Produtos Biológicos/farmacologia , Fungos/isolamento & purificação , Fungos/metabolismo , Holothuria/microbiologia , Micobioma , Animais , Produtos Biológicos/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Fungos/classificação , Fungos/genética , Células Hep G2 , Humanos , Células-Tronco Mesenquimais , Osteogênese/efeitos dos fármacos
2.
Epidemiol Psychiatr Sci ; 29: e18, 2019 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-30712520

RESUMO

AIMS: To examine the impact of multiple psychiatric disorders over the lifetime on risk of mortality in the general population. METHODS: Data came from a random community-based sample of 1397 adults in Atlantic Canada, recruited in 1992. Major depression, dysthymia, panic disorder, generalised anxiety disorder and alcohol use disorders were assessed using the Diagnostic Interview Schedule (DIS). Vital status of participants through 2011 was determined using probabilistic linkages to the Canadian Mortality Database. Cox proportional hazard models with age at study entry as the time scale were used to investigate the relationship between DIS diagnoses and mortality, adjusted for participant education, smoking and obesity at baseline. RESULTS: Results suggested that mood and anxiety disorders rarely presented in isolation - the majority of participants experienced multiple psychiatric disorders over the lifetime. Elevated risk of death was found among men with both major depression and dysthymia (HR 2.56; 95% CI 1.12-5.89), depression and alcohol use disorders (HR 2.45; 95% CI 1.18-5.10) and among men and women who experienced both panic disorder and alcohol use disorders (HR 3.80; 95% CI 1.19-12.16). CONCLUSION: The experience of multiple mental disorders over the lifetime is extremely common, and associated with increased risk of mortality, most notably among men. Clinicians should be aware of the importance of considering contemporaneous symptoms of multiple psychiatric conditions.


Assuntos
Transtornos Mentais/epidemiologia , Adulto , Canadá/epidemiologia , Estudos de Coortes , Feminino , Humanos , Masculino , Transtornos Mentais/mortalidade
3.
Oncogene ; 37(16): 2137-2149, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29367765

RESUMO

Adult Mesenchymal Stem Cells (MSCs) have a well-established tumor-homing capacity, highlighting potential as tumor-targeted delivery vehicles. MSCs secrete extracellular vesicle (EV)-encapsulated microRNAs, which play a role in intercellular communication. The aim of this study was to characterize a potential tumor suppressor microRNA, miR-379, and engineer MSCs to secrete EVs enriched with miR-379 for in vivo therapy of breast cancer. miR-379 expression was significantly reduced in lymph node metastases compared to primary tumor tissue from the same patients. A significant reduction in the rate of tumor formation and growth in vivo was observed in T47D breast cancer cells stably expressing miR-379. In more aggressive HER2-amplified HCC-1954 cells, HCC-379 and HCC-NTC tumor growth rate in vivo was similar, but increased tumor necrosis was observed in HCC-379 tumors. In response to elevated miR-379, COX-2 mRNA and protein was also significantly reduced in vitro and in vivo. MSCs were successfully engineered to secrete EVs enriched with miR-379, with the majority found to be of the appropriate size and morphology of exosomal EVs. Administration of MSC-379 or MSC-NTC cells, or EVs derived from either cell population, resulted in no adverse effects in vivo. While MSC-379 cells did not impact tumor growth, systemic administration of cell-free EVs enriched with miR-379 was demonstrated to have a therapeutic effect. The data presented support miR-379 as a potent tumor suppressor in breast cancer, mediated in part through regulation of COX-2. Exploiting the tumor-homing capacity of MSCs while engineering the cells to secrete EVs enriched with miR-379 holds exciting potential as an innovative therapy for metastatic breast cancer.


Assuntos
Neoplasias da Mama/terapia , Sistemas de Liberação de Medicamentos/métodos , Vesículas Extracelulares/metabolismo , Terapia Genética/métodos , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/fisiologia , MicroRNAs/administração & dosagem , Células-Tronco Adultas/transplante , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Células Cultivadas , Composição de Medicamentos/métodos , Vesículas Extracelulares/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Metástase Linfática , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/genética , Metástase Neoplásica , Terapias em Estudo/métodos , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Int J Cancer ; 142(10): 2056-2067, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29266277

RESUMO

Mesenchymal stem cells (MSCs) are a heterogeneous population of multipotent cells that are capable of differentiating into osteocytes, chondrocytes and adipocytes. Recently, MSCs have been found to home to the tumour site and engraft in the tumour stroma. However, it is not yet known whether they have a tumour promoting or suppressive function. We investigated the interaction between prostate cancer cell lines 22Rv1, DU145 and PC3, and bone marrow-derived MSCs. MSCs were 'educated' for extended periods in prostate cancer cell conditioned media and PC3-educated MSCs were found to be the most responsive with a secretory profile rich in pro-inflammatory cytokines. PC3-educated MSCs secreted increased osteopontin (OPN), interleukin-8 (IL-8) and fibroblast growth factor-2 (FGF-2) and decreased soluble fms-like tyrosine kinase-1 (sFlt-1) compared to untreated MSCs. PC3-educated MSCs showed a reduced migration and proliferation capacity that was dependent on exposure to PC3-conditioned medium. Vimentin and α-smooth muscle actin (αSMA) expression was decreased in PC3-educated MSCs compared to untreated MSCs. PC3 and DU145 education of healthy donor and prostate cancer patient-derived MSCs led to a reduced proportion of FAP+ αSMA+ cells contrary to characteristics commonly associated with cancer associated fibroblasts (CAFs). The migration of PC3 cells was increased toward both PC3-educated and DU145-educated MSCs compared to untreated MSCs, while DU145 migration was only enhanced toward patient-derived MSCs. In summary, MSCs developed an altered phenotype in response to prostate cancer conditioned medium which resulted in increased secretion of pro-inflammatory cytokines, modified functional activity and the chemoattraction of prostate cancer cells.


Assuntos
Citocinas/metabolismo , Citocinas/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Neoplasias da Próstata/metabolismo , Adulto , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Meios de Cultivo Condicionados , Humanos , Masculino , Células-Tronco Mesenquimais/patologia , Pessoa de Meia-Idade , Metástase Neoplásica , Neoplasias da Próstata/patologia , Adulto Jovem
5.
Drug Alcohol Depend ; 149: 25-30, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25666362

RESUMO

BACKGROUND: Since 2007, there has been a rise in the use of electronic cigarettes (e-cigarettes). The present study uses cross-sectional data (2013) to examine prevalence, correlates and susceptibility to e-cigarettes among young adults. METHODS: Data were collected using an Internet survey from a convenience sample of 1437, 18-23 year olds attending four colleges/universities in Upstate New York. Results were summarized using descriptive statistics; logistic regression models were analyzed to identify correlates of e-cigarette use and susceptibility to using e-cigarettes. RESULTS: Nearly all respondents (95.5%) reported awareness of e-cigarettes; 29.9% were ever users and 14.9% were current users. Younger students, males, non-Hispanic Whites, respondents reporting average/below average school ability, ever smokers and experimenters of tobacco cigarettes, and those with lower perceptions of harm regarding e-cigarettes demonstrated higher odds of ever use or current use. Risky behaviors (i.e., tobacco, marijuana or alcohol use) were associated with using e-cigarettes. Among never e-cigarette users, individuals involved in risky behaviors or, with lower harm perceptions for e-cigarettes, were more susceptible to future e-cigarette use. CONCLUSIONS: More e-cigarette users report use of another nicotine product besides e-cigarettes as the first nicotine product used; this should be considered when examining whether e-cigarette use is related to cigarette susceptibility. Involvement in risky behaviors is related to e-cigarette use and susceptibility to e-cigarette use. Among college students, e-cigarette use is more likely to occur in those who have also used other tobacco products, marijuana, and/or alcohol.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Assunção de Riscos , Fumar/epidemiologia , Fumar/psicologia , Fatores Etários , Consumo de Bebidas Alcoólicas/psicologia , Estudos Transversais , Suscetibilidade a Doenças , Feminino , Humanos , Masculino , Fumar Maconha/psicologia , Prevalência , Fatores Sexuais , Fatores Socioeconômicos , População Branca , Adulto Jovem
6.
Ann Biomed Eng ; 43(9): 2069-82, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25589372

RESUMO

The main objective of this study was to evaluate the effectiveness of a mesenchymal stem cell (MSC)-seeded polyethylene-oxide-terephthalate/polybutylene-terephthalate (PEOT/PBT) scaffold for cartilage tissue repair in an osteochondral defect using a rabbit model. Material characterisation using scanning electron microscopy indicated that the scaffold had a 3D architecture characteristic of the additive manufacturing fabrication method, with a strut diameter of 296 ± 52 µm and a pore size of 512 ± 22 µm × 476 ± 25 µm × 180 ± 30 µm. In vitro optimisation revealed that the scaffold did not generate an adverse cell response, optimal cell loading conditions were achieved using 50 µg/ml fibronectin and a cell seeding density of 25 × 10(6) cells/ml and glycosaminoglycan (GAG) accumulation after 28 days culture in the presence of TGFß3 indicated positive chondrogenesis. Cell-seeded scaffolds were implanted in osteochondral defects for 12 weeks, with cell-free scaffolds and empty defects employed as controls. On examination of toluidine blue staining for chondrogenesis and GAG accumulation, both the empty defect and the cell-seeded scaffold appeared to promote repair. However, the empty defect and the cell-free scaffold stained positive for collagen type I or fibrocartilage, while the cell-seeded scaffold stained positive for collagen type II indicative of hyaline cartilage and was statistically better than the cell-free scaffold in the blinded histological evaluation. In summary, MSCs in combination with a 3D PEOT/PBT scaffold created a reparative environment for cartilage repair.


Assuntos
Cartilagem/lesões , Cartilagem/metabolismo , Condrogênese , Células-Tronco Mesenquimais/metabolismo , Poliésteres , Polietilenoglicóis , Alicerces Teciduais , Animais , Cartilagem/inervação , Células-Tronco Mesenquimais/patologia , Coelhos
7.
Osteoarthritis Cartilage ; 22(8): 1167-75, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24911520

RESUMO

OBJECTIVE: Mesenchymal stem cells (MSCs) are a promising cell type for the repair of damaged cartilage in osteoarthritis (OA). However, OA synovial fluid and factors secreted by synovium impede chondrogenic differentiation of MSCs, and the mechanism responsible for this effect remains unclear. In this study, we sought to investigate whether M1 and M2 synovial macrophages can contribute to the inhibition of MSC chondrogenesis. DESIGN: The constitution of synovial macrophage subsets was analysed by immunohistochemical staining of human OA synovium sections for CD86 (M1 marker) and CD206 (M2 marker). To assess the effect of synovial macrophages on chondrogenesis, collagen type II (COL2) and aggrecan (ACAN) gene expression were compared between MSCs undergoing chondrogenic differentiation in medium conditioned (CM) by human OA synovial explants, human synovial macrophages and fibroblasts, or peripheral blood derived primary human monocytes differentiated towards an M1 or M2 phenotype. RESULTS: OA synovium contained both M1 and M2 macrophages. Medium conditioned by synovial macrophages (CD45 + plastic adherent cells) down-regulated chondrogenic gene expression by MSCs. Additionally, CM of M1 polarised monocytes significantly decreased COL2 and ACAN gene expression by MSCs; this effect was not observed for treatment with CM of M2 polarised monocytes. CONCLUSION: MSC chondrogenesis is inhibited by OA synovium CM through factors secreted by synovial macrophages and our findings suggest that M1 polarised subsets are potential mediators of this anti-chondrogenic effect. Modulation of macrophage phenotype may serve as a beneficial strategy to maximise the potential of MSCs for efficient cartilage repair.


Assuntos
Diferenciação Celular/imunologia , Condrogênese/imunologia , Macrófagos/imunologia , Células-Tronco Mesenquimais/imunologia , Osteoartrite/imunologia , RNA Mensageiro/genética , Membrana Sinovial/imunologia , Adulto , Idoso , Agrecanas/metabolismo , Antígeno B7-2/metabolismo , Cartilagem Articular/imunologia , Quimiocinas CC/genética , Condrócitos , Colágeno Tipo II/metabolismo , Meios de Cultivo Condicionados , Feminino , Perfilação da Expressão Gênica , Humanos , Interleucina-6/genética , Lectinas Tipo C/metabolismo , Masculino , Receptor de Manose , Lectinas de Ligação a Manose/metabolismo , Pessoa de Meia-Idade , Monócitos/imunologia , Receptores de Superfície Celular/metabolismo , Líquido Sinovial/imunologia
8.
Cell Death Differ ; 21(10): 1600-12, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24902899

RESUMO

Both receptor-interacting protein kinase 1 (RIPK1) and RIPK3 can signal cell death following death receptor ligation. To study the requirements for RIPK-triggered cell death in the absence of death receptor signaling, we engineered inducible versions of RIPK1 and RIPK3 that can be activated by dimerization with the antibiotic coumermycin. In the absence of TNF or other death ligands, expression and dimerization of RIPK1 was sufficient to cause cell death by caspase- or RIPK3-dependent mechanisms. Dimerized RIPK3 induced cell death by an MLKL-dependent mechanism but, surprisingly, also induced death mediated by FADD, caspase 8 and RIPK1. Catalytically active RIPK3 kinase domains were essential for MLKL-dependent but not for caspase 8-dependent death. When RIPK1 or RIPK3 proteins were dimerized, the mode of cell death was determined by the availability of downstream molecules such as FADD, caspase 8 and MLKL. These observations imply that rather than a 'switch' operating between the two modes of cell death, the final mechanism depends on levels of the respective signaling and effector proteins.


Assuntos
Apoptose/genética , Multimerização Proteica/genética , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Proteínas Recombinantes/metabolismo , Aminocumarinas/metabolismo , Animais , Caspase 3/metabolismo , Caspase 8/metabolismo , Linhagem Celular , Proteína de Domínio de Morte Associada a Fas/metabolismo , Camundongos , Camundongos Knockout , Proteínas Quinases/metabolismo , Estrutura Quaternária de Proteína , Estrutura Terciária de Proteína , Proteínas Recombinantes/genética , Transdução de Sinais/genética , Fator de Necrose Tumoral alfa/metabolismo
9.
Cell Death Dis ; 5: e1086, 2014 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-24577084

RESUMO

Necroptosis is a mechanism by which cells can kill themselves that does not require caspase activity or the presence of the pro-apoptotic Bcl-2 family members Bax or Bak. It has been reported that RIPK3 (receptor interacting protein kinase 3) activates MLKL (mixed lineage kinase domain-like) to cause cell death that requires dynamin-related protein 1 (Drp1), because survival was increased in cells depleted of Drp1 or treated with the Drp1 inhibitor mdivi-1. To analyze necroptosis in a system that does not require addition of tumor necrosis factor (TNF), we used a construct that allows RIPK3 to be induced in cells, and then dimerized via an E. coli gyrase domain fused to its carboxyl-terminus, using the dimeric gyrase binding antibiotic coumermycin. We have previously shown elsewhere that RIPK3 dimerized in this manner not only induces necroptosis but also apoptosis, which can be inhibited by the broad-spectrum caspase inhibitor Q-VD-OPh (QVD). In response to RIPK3 dimerization, wild-type mouse embryonic fibroblasts (MEFs) underwent cell death that was reduced but not completely blocked by QVD. In contrast, death upon dimerization of RIPK3 in Mlkl(-/-) MEFs was completely inhibited with QVD, confirming that MLKL is required for necroptosis. Similar to wild-type MEFs, most Drp1(-/-) MEFs died when RIPK3 was activated, even in the presence of QVD. Furthermore, overexpression of wild-type MLKL or dominant active mutants of MLKL (Q343A or S345E/S347E) caused death of wild-type and Drp1(-/-) MEFs that was not inhibited with QVD. These results indicate that necroptosis caused by RIPK3 requires MLKL but not Drp1.


Assuntos
Apoptose , Dinaminas/metabolismo , Fibroblastos/enzimologia , Proteínas Quinases/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Transdução de Sinais , Aminocumarinas/farmacologia , Animais , Antibacterianos/farmacologia , Apoptose/efeitos dos fármacos , Inibidores de Caspase/farmacologia , Linhagem Celular , Dinaminas/deficiência , Dinaminas/genética , Fibroblastos/efeitos dos fármacos , Fibroblastos/patologia , Camundongos , Camundongos Knockout , Mutação , Necrose , Proteínas Quinases/deficiência , Proteínas Quinases/genética , Multimerização Proteica , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Proteínas Recombinantes de Fusão/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Transfecção , Fator de Necrose Tumoral alfa/farmacologia
10.
Eur Cell Mater ; 27: 112-23; discussion 123, 2014 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-24488855

RESUMO

Hydrogels pose interesting features for cartilage regeneration strategies, such as the option for injectability and in situ gelation resulting in optimal filling of defects. We aimed to study different hydrogels for their capability to support chondrogenesis of human bone marrow-derived mesenchymal stem cells (hBMSCs). hBMSCs were encapsulated in alginate, alginate with hyaluronic acid (alginate/HA), fibrin or thermoresponsive HA grafted with poly(N-isopropyl acrylamide) side-chains (HA-pNIPAM). Glycosaminoglycan production and cartilage-related gene expression were significantly higher in hBMSC-alginate and hBMSC-fibrin constructs than in the other constructs. Supplementation of alginate with HA was not beneficial. hBMSC-alginate, hBMSC-fibrin and hBMSC-HA-pNIPAM constructs were placed in simulated defects in osteochondral biopsies and cultured in vitro for 28 d. Biopsies containing hBMSC-alginate and hBMSC-fibrin were implanted subcutaneously in nude mice for 12 weeks. hBMSC-alginate constructs had significantly higher cartilage-related gene expression after 28 d of culture as well as significantly more safranin-O positive repair tissue after 12 weeks in vivo than hBMSC-fibrin constructs. Although initial experiments with hBMSC-hydrogel constructs suggested comparable results of hBMSC-alginate, hBMSC-fibrin and hBMSC-HA-pNIPAM constructs, culture in the osteochondral biopsy model in vitro as well as in vivo revealed differences, suggests that chondrogenesis of hBMSCs in an osteochondral environment is hydrogel-dependent.


Assuntos
Condrócitos/citologia , Condrogênese , Hidrogéis/farmacologia , Células-Tronco Mesenquimais/citologia , Resinas Acrílicas/farmacologia , Adulto , Alginatos/farmacologia , Animais , Cartilagem/metabolismo , Cartilagem/fisiologia , Bovinos , Células Cultivadas , Condrócitos/efeitos dos fármacos , Condrócitos/metabolismo , Fibrina/farmacologia , Ácido Glucurônico/farmacologia , Regeneração Tecidual Guiada , Ácidos Hexurônicos/farmacologia , Humanos , Ácido Hialurônico/farmacologia , Hidrogéis/química , Masculino , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Nus , Osteocondrose/cirurgia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Regeneração , Alicerces Teciduais/química
11.
Acta Biomater ; 9(12): 9303-16, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23958783

RESUMO

This paper demonstrates a method to engineer, in vitro, a nascent microvasculature within a collagen-glycosaminoglycan scaffold with a view to overcoming the major issue of graft failure due to avascular necrosis of tissue-engineered constructs. Human umbilical vein endothelial cells (ECs) were cultured alone and in various co-culture combinations with human mesenchymal stem cells (MSCs) to determine their vasculogenic abilities in vitro. Results demonstrated that the delayed addition of MSCs to pre-formed EC networks, whereby MSCs act as pericytes to the nascent vessels, resulted in the best developed vasculature. The results also demonstrate that the crosstalk between ECs and MSCs during microvessel formation occurs in a highly regulated, spatio-temporal fashion, whereby the initial seeding of ECs results in platelet derived growth factor (PDGF) release; the subsequent addition of MSCs 3 days later leads to a cessation in PDGF production, coinciding with increased vascular endothelial cell growth factor expression and enhanced vessel formation. Functional assessment of these pre-engineered constructs in a subcutaneous rat implant model demonstrated anastomosis between the in vitro engineered vessels and the host vasculature, with significantly increased vascularization occurring in the co-culture group. This study has thus provided new information on the process of in vitro vasculogenesis within a three-dimensional porous scaffold for tissue engineering and demonstrates the potential for using these vascularized scaffolds in the repair of critical sized bone defects.


Assuntos
Colágeno/farmacologia , Glicosaminoglicanos/farmacologia , Células Endoteliais da Veia Umbilical Humana/citologia , Células-Tronco Mesenquimais/citologia , Neovascularização Fisiológica/efeitos dos fármacos , Alicerces Teciduais/química , Angiografia , Animais , Vasos Sanguíneos/patologia , Bovinos , Técnicas de Cocultura , Humanos , Microscopia de Fluorescência por Excitação Multifotônica , Fator de Crescimento Derivado de Plaquetas/metabolismo , Ratos , Coloração e Rotulagem , Fator A de Crescimento do Endotélio Vascular/metabolismo , Microtomografia por Raio-X
12.
Breast Cancer Res Treat ; 124(2): 317-26, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20087650

RESUMO

Bone marrow-derived mesenchymal stem cells (MSCs) are known to specifically migrate to and engraft at tumour sites. Understanding interactions between cancer cells and MSCs has become fundamental to determining whether MSC-tumour interactions should be harnessed for delivery of therapeutic agents or considered a target for intervention. Breast Cancer Cell lines (MDA-MB-231, T47D & SK-Br3) were cultured alone or on a monolayer of MSCs, and retrieved using epithelial specific magnetic beads. Alterations in expression of 90 genes associated with breast tumourigenicity were analysed using low-density array. Expression of markers of epithelial-mesenchymal transition (EMT) and array results were validated using RQ-PCR. Co-cultured cells were analysed for changes in protein expression, growth pattern and morphology. Gene expression and proliferation assays were also performed on indirect co-cultures. Following direct co-culture with MSCs, breast cancer cells expressed elevated levels of oncogenes (NCOA4, FOS), proto-oncogenes (FYN, JUN), genes associated with invasion (MMP11), angiogenesis (VEGF) and anti-apoptosis (IGF1R, BCL2). However, universal downregulation of genes associated with proliferation was observed (Ki67, MYBL2), and reflected in reduced ATP production in response to MSC-secreted factors. Significant upregulation of EMT specific markers (N-cadherin, Vimentin, Twist and Snail) was also observed following co-culture with MSCs, with a reciprocal downregulation in E-cadherin protein expression. These changes were predominantly cell contact mediated and appeared to be MSC specific. Breast cancer cell morphology and growth pattern also altered in response to MSCs. MSCs may promote breast cancer metastasis through facilitation of EMT.


Assuntos
Neoplasias da Mama/patologia , Células Epiteliais/patologia , Transição Epitelial-Mesenquimal , Células-Tronco Mesenquimais/patologia , Comunicação Parácrina , Microambiente Tumoral , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Forma Celular , Técnicas de Cocultura , Meios de Cultivo Condicionados/metabolismo , Células Epiteliais/metabolismo , Transição Epitelial-Mesenquimal/genética , Feminino , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Células-Tronco Mesenquimais/metabolismo , Microscopia Confocal , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
13.
Clin Radiol ; 64(10): 1026-34, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19748009

RESUMO

Magnetic reasonance (MR) enterography enables high contrast resolution depiction of the location and cause of bowel obstruction through a combination of predictable luminal distension and multiplanar imaging capabilities. Furthermore, because the patient is not exposed to ionizing radiation, sequential "dynamic" MR imaging can be performed repeatedly over time further facilitating depiction of the site and/or the cause of obstruction. With increasing availability of MR imaging and standardization of the oral contrast medium regimens, it is likely that this technique will assume an ever-increasing role in the evaluation of small bowel dilation in the coming years. We illustrate the utility of MR enterography in the evaluation of small bowel dilation, whether it be mechanical, functional (e.g., ileus), or related to infiltrative mural disease.


Assuntos
Enteropatias/diagnóstico , Intestino Delgado/patologia , Imagem Cinética por Ressonância Magnética/métodos , Adulto , Idoso , Meios de Contraste , Dilatação Patológica/diagnóstico , Enterite/diagnóstico , Feminino , Hérnia/diagnóstico , Humanos , Íleus/diagnóstico , Processamento de Imagem Assistida por Computador/métodos , Neoplasias Intestinais/diagnóstico , Obstrução Intestinal/diagnóstico , Volvo Intestinal/diagnóstico , Masculino , Pessoa de Meia-Idade
14.
Clin Radiol ; 64(7): 724-33, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19520217

RESUMO

Gastrointestinal complications of chemotherapy may be serious and potentially life-threatening. Familiarity with and awareness of the potential complications associated with various chemotherapeutic agents/regimens is paramount to enable accurate and timely diagnosis. In this article we review the radiological manifestations of the most notable gastrointestinal complications associated with chemotherapeutic administration.


Assuntos
Antineoplásicos/efeitos adversos , Gastroenteropatias/induzido quimicamente , Gastroenteropatias/diagnóstico por imagem , Adulto , Idoso , Enterocolite Neutropênica/induzido quimicamente , Enterocolite Neutropênica/diagnóstico por imagem , Enterocolite Pseudomembranosa/induzido quimicamente , Enterocolite Pseudomembranosa/diagnóstico por imagem , Feminino , Hemorragia Gastrointestinal/induzido quimicamente , Hemorragia Gastrointestinal/diagnóstico por imagem , Humanos , Perfuração Intestinal/induzido quimicamente , Perfuração Intestinal/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos
15.
Psychol Med ; 39(7): 1055-64, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18940025

RESUMO

BACKGROUND: The role played by anxiety in the history of psychiatric epidemiology has not been well recognized. Such lack of understanding retarded the incremental growth of psychiatric research in general populations. It seems useful to look back on this history while deliberations are being carried out about how anxiety will be presented in DSM-V. METHOD: Drawing on the literature and our own research, we examined work that was carried out during and after the Second World War by a Research Branch of the United States War Department, by the Stirling County Study, and by the Midtown Manhattan Study. The differential influences of Meyerian psychobiology and Freudian psychoanalysis are noted. RESULTS: The instruments developed in the early epidemiologic endeavors used questions about nervousness, palpitations, sweating, trembling, shortness of breath, upset stomach, etc. These symptoms are important features of what the clinical literature called 'manifest', 'free-floating' or 'chronic anxiety'. A useful descriptive name is 'autonomic anxiety'. CONCLUSIONS: Although not focusing on specific circumstances as in Panic and Phobic disorders, a non-specific form of autonomic anxiety is a common, disabling and usually chronic disorder that received empirical verification in studies of several community populations. It is suggested that two types of general anxiety may need to be recognized, one dominated by excessive worry and feelings of stress, as in the current DSM-IV definition of Generalized Anxiety Disorder (GAD), and another emphasizing frequent unexplainable autonomic fearfulness, as in the early epidemiologic studies.


Assuntos
Transtornos de Ansiedade/história , Manual Diagnóstico e Estatístico de Transtornos Mentais , Testes Psicológicos/história , Transtornos Psicofisiológicos/história , História do Século XX , Humanos , Estados Unidos
16.
Clin Cancer Res ; 13(17): 5020-7, 2007 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-17785552

RESUMO

PURPOSE: Major barriers to effective adenovirus-based gene therapy include induction of an immune response and tumor-specific targeting of vectors. The use of mesenchymal stem cells (MSC) as systemic delivery vehicles for therapeutic genes has been proposed as a result of their combined ability to home in on the tumor site and evade the host immune response. This study is aimed at investigating factors mediating homing of human MSCs to breast cancer primary cultures and cell lines in vitro and in vivo. EXPERIMENTAL DESIGN: Fluorescently labeled MSCs were given to mice bearing breast cancer xenografts, and tumor tissue was harvested to detect MSC engraftment. MSC migration in response to primary breast tumors in vitro was quantified, and chemokines secreted by tumor cells were identified. The role of monocyte chemotactic protein-1 (MCP-1) in cell migration was investigated using antibodies and standards of the chemokine. Serum MCP-1 was measured in 125 breast cancer patients and 86 healthy controls. RESULTS: Engrafted MSCs were detected in metastatic breast tumors in mice after systemic administration. There was a significant increase in MSC migration in response to primary breast tumor cells in vitro (6-fold to 11-fold increase). Tumor explants secreted a variety of chemokines including GROalpha, MCP-1, and stromal cell-derived factor-1alpha. An MCP-1 antibody caused a significant decrease (37-42%) in MSC migration to tumors. Serum MCP-1 levels were significantly higher in postmenopausal breast cancer patients than age-matched controls (P < 0.05). CONCLUSIONS: These results highlight a role for tumor-secreted MCP-1 in stimulating MSC migration and support the potential of these cells as tumor-targeted delivery vehicles for therapeutic agents.


Assuntos
Neoplasias da Mama/metabolismo , Movimento Celular , Quimiocina CCL2/fisiologia , Células-Tronco Mesenquimais/fisiologia , Neoplasias da Mama/sangue , Linhagem Celular Tumoral , Quimiocina CCL2/sangue , Feminino , Humanos
17.
Clin Exp Immunol ; 149(2): 353-63, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17521318

RESUMO

The ability of mesenchymal stem cells (MSC) to suppress alloresponsiveness is poorly understood. Herein, an allogeneic mixed lymphocyte response was used as a model to investigate the mechanisms of MSC-mediated immunomodulation. Human MSC are demonstrated to express the immunosuppressive cytokines hepatocyte growth factor (HGF), interleukin (IL)-10 and transforming growth factor (TGF)-beta1 at concentrations that suppress alloresponses in vitro. MSC also express cyclooxygenase 1 and 2 and produce prostaglandin E2 constitutively. Blocking studies with indomethacin confirmed that prostaglandins contribute to MSC-mediated allosuppression. The proinflammatory cytokine interferon (IFN)-gamma did not ablate MSC inhibition of alloantigen-driven proliferation but up-regulated HGF and TGF-beta1. IFN-gamma also induced expression of indoleamine 2,3, dioxygenase (IDO), involved in tryptophan catabolism. Use of an antagonist, 1-methyl-L-tryptophan, restored alloresponsiveness and confirmed an IDO contribution to IFN-gamma-induced immunomodulation by MSC. Addition of the tryptophan catabolite kynurenine to mixed lymphocyte reactions (MLR), blocked alloproliferation. These findings support a model where IDO exerts its effect through the local accumulation of tryptophan metabolites rather than through tryptophan depletion. Taken together, these data demonstrate that soluble factors, or products derived from MSC, modulate immune responses and suggest that MSC create an immunosuppressive microenvironment capable of modulating alloresponsiveness even in the presence of IFN-gamma.


Assuntos
Tolerância Imunológica/imunologia , Interferon gama/imunologia , Células-Tronco Mesenquimais/imunologia , Adulto , Proliferação de Células , Células Cultivadas , Ciclo-Oxigenase 1/biossíntese , Ciclo-Oxigenase 2/biossíntese , Dinoprostona/biossíntese , Fator de Crescimento de Hepatócito/biossíntese , Humanos , Indolamina-Pirrol 2,3,-Dioxigenase/biossíntese , Interleucina-10/biossíntese , Ativação Linfocitária/imunologia , Teste de Cultura Mista de Linfócitos , Proteínas Recombinantes , Fator de Crescimento Transformador beta1/biossíntese
18.
J Clin Oncol ; 19(15): 3524-31, 2001 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-11481359

RESUMO

PURPOSE: Recommended surveillance for BRCA1 and BRCA2 mutation carriers includes regular mammography and clinical breast examination, although the effectiveness of these screening techniques in mutation carriers has not been established. The purpose of the present study was to compare breast magnetic resonance imaging (MRI) with ultrasound, mammography, and physical examination in women at high risk for hereditary breast cancer. PATIENTS AND METHODS: A total of 196 women, aged 26 to 59 years, with proven BRCA1 or BRCA2 mutations or strong family histories of breast or ovarian cancer underwent mammography, ultrasound, MRI, and clinical breast examination on a single day. A biopsy was performed when any of the four investigations was judged to be suspicious for malignancy. RESULTS: Six invasive breast cancers and one noninvasive breast cancer were detected among the 196 high-risk women. Five of the invasive cancers occurred in mutation carriers, and the sixth occurred in a woman with a previous history of breast cancer. The prevalence of invasive or noninvasive breast cancer in the 96 mutation carriers was 6.2%. All six invasive cancers were detected by MRI, all were 1.0 cm or less in diameter, and all were node-negative. In contrast, only three invasive cancers were detected by ultrasound, two by mammography, and two by physical examination. The addition of MRI to the more commonly available triad of mammography, ultrasound, and breast examination identified two additional invasive breast cancers that would otherwise have been missed. CONCLUSION: Breast MRI may be superior to mammography and ultrasound for the screening of women at high risk for hereditary breast cancer.


Assuntos
Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Adulto , Proteína BRCA2 , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Feminino , Genes BRCA1/genética , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Humanos , Imageamento por Ressonância Magnética , Mamografia , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , Exame Físico , Fatores de Transcrição/genética , Ultrassonografia
19.
Exp Cell Res ; 268(2): 189-200, 2001 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-11478845

RESUMO

Transforming growth factor (TGF)-beta-induced chondrogenesis of mesenchymal stem cells derived from bone marrow involves the rapid deposition of a cartilage-specific extracellular matrix. The sequential events in this pathway leading from the undifferentiated stem cell to a mature chondrocyte were investigated by analysis of key matrix elements. Differentiation was rapidly induced in cells cultured in the presence of TGF-beta 3 or -beta 2 and was accompanied by the early expression of fibromodulin and cartilage oligomeric matrix protein. An increase in aggrecan and versican core protein synthesis defined an intermediate stage, which also involved the small leucine-rich proteoglycans decorin and biglycan. This was followed by the appearance of type II collagen and chondroadherin. The pathway was also characterized by the appearance of type X collagen, usually associated with hypertrophic cartilage. There was also a change in the pattern of sulfation of chondroitin sulfate, with a progressive increase in the proportion of 6-sulfated species. The major proportion of newly synthesized glycosaminoglycan was part of an aggregating proteoglycan network. These data allow us to define the phenotype of the differentiated cell and to understand in greater detail the sequential process of matrix assembly.


Assuntos
Células da Medula Óssea/citologia , Condrogênese , Proteínas da Matriz Extracelular/biossíntese , Mesoderma/citologia , Células-Tronco/citologia , Agrecanas , Biglicano , Células da Medula Óssea/efeitos dos fármacos , Proteínas de Transporte/biossíntese , Proteínas de Transporte/genética , Proteína de Matriz Oligomérica de Cartilagem , Diferenciação Celular , Proteoglicanas de Sulfatos de Condroitina/biossíntese , Proteoglicanas de Sulfatos de Condroitina/genética , Decorina , Proteínas da Matriz Extracelular/genética , Fibromodulina , Glicoproteínas/biossíntese , Glicoproteínas/genética , Glicosaminoglicanos/biossíntese , Humanos , Lectinas Tipo C , Proteínas Matrilinas , Mesoderma/efeitos dos fármacos , Isoformas de Proteínas , Proteoglicanas/biossíntese , Proteoglicanas/genética , Células-Tronco/efeitos dos fármacos , Ésteres do Ácido Sulfúrico/metabolismo , Fator de Crescimento Transformador beta/farmacologia , Versicanas
20.
World J Surg ; 25(3): 373-9; discussion 379-80, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11343197

RESUMO

Percutaneous needle biopsy (PNB) of the lung is a commonly performed procedure, mainly used for the investigation of solitary pulmonary nodules. Developments in imaging, particularly computed tomography (CT), have enable accurate preliminary assessment and targeting of lesions. Improvements in needle design ensure the provision of diagnostic samples for both cytologic and histologic assessment; and the development of immunocytochemistry and immunohistochemistry have allowed improved accuracy in diagnosis. A significant improvement in diagnostic accuracy for benign lesions has been associated with the use of cutting needles that provide cores for histologic diagnosis, in contrast to cytologic analysis from fine-needle aspiration. The complications of PNB are well recorded and have not changed significantly with the newer imaging techniques and needles. The preliminary assessment of solitary pulmonary nodules, and the pretest likelihood of malignancy, has improved using contrast-enhanced CT and positron emission tomography; the latter modality is increasingly having a major impact on the investigation of patients with suspected malignancy. The performance of PNB must always be determined on an individual case basis and when the result is likely to affect management. The complementary roles of PNB, bronchoscopic biopsy, and video-assisted thoracoscopic biopsy continue to evolve.


Assuntos
Biópsia por Agulha/métodos , Pneumopatias/patologia , Nódulo Pulmonar Solitário/patologia , Biópsia por Agulha/efeitos adversos , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA