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1.
J Endovasc Ther ; : 15266028221148383, 2023 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-36680500

RESUMO

PURPOSE: Ascending aorta (AAo) acute pathology still has an open-surgery indication with a high mortality rate associated to cardiopulmonary bypass and circulatory arrest. In these cases, the endovascular aortic approach could be an excellent option. The aim of the present study is to detail an optimized technique for the endovascular treatment of AAo diseases, based on thoracic endovascular aortic repair (TEVAR) and transcatheter aortic valve implantation (TAVI) procedures. TECHNIQUE: The procedure implies the usual preparation for TEVAR and TAVI implants. A transient pacemaker lead is necessary to deliver the prosthesis under "rapid pacing." As in the TAVI technique, a final high-support guidewire is placed at the left ventricle. The proximal landing zone is the sinotubular junction (zone 0B). Transesophageal echocardiography is essential to ensure aortic valve function and patency in coronary arteries during the delivery. To assess a potential occlusion of the brachiocephalic artery, a guidewire is positioned in the descending aorta from the axillary artery. Finally, a noncovered stent is implanted to stabilize the AAo prosthesis. CONCLUSION: The technique presented here can standardize a safe and reproducible procedure to endovascular repair of AAo diseases. However, new devices specifically designed for the AAo could facilitate the transcatheter approach. CLINICAL IMPACT: Ascending aorta acute pathology still has an open-surgery indication with high mortality rate associated to cardiopulmonary bypass and circulatory arrest. Moreover, near 30% of patients are not considered suitable for surgery because of age, critical situation or the presence of severe comorbidities. The present study provides a detailed and optimized technique for the endovascular treatment of ascending aorta disease, based on TEVAR and TAVI procedures.

2.
Thorac Cardiovasc Surg ; 68(1): 68-71, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31630382

RESUMO

The use of conventional implantable cardioverter-defibrillators (ICDs) in children presents important technical challenges. We present the surgical technique necessary to adapt the subcutaneous ICD (S-ICD) implantation designed for adults, to children, including patients weighing less than 20 kg. The implant procedure implies a two-incision technique and interfascial serratus anterior-latissimus dorsi dissection to accommodate the device. S-ICD implantation was successfully performed in three patients of 19, 28, and 24 kg, respectively, two of them suffered cardiorespiratory arrest. Intermuscular thoracic implantation of S-ICD might represent an effective strategy for primary or secondary prevention of sudden cardiac death in pediatric patients.


Assuntos
Morte Súbita Cardíaca/prevenção & controle , Desfibriladores Implantáveis , Cardioversão Elétrica/instrumentação , Prevenção Primária/instrumentação , Implantação de Prótese/instrumentação , Prevenção Secundária/instrumentação , Músculos Superficiais do Dorso/cirurgia , Fatores Etários , Peso Corporal , Criança , Pré-Escolar , Dissecação , Cardioversão Elétrica/efeitos adversos , Feminino , Humanos , Masculino , Implantação de Prótese/efeitos adversos , Fatores de Risco , Resultado do Tratamento
3.
Gynecol Obstet Invest ; 85(3): 259-266, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32289805

RESUMO

BACKGROUND: The differential expression of oestrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor 2 (HER2) or Ki-67 between primary tumour and the recurrence has been described. We aimed to determine these changes and their prognostic implications. PATIENTS AND METHODS: We retrospectively reviewed 45 breast cancer patients with relapsed biopsy that were classified into local relapse (LR) or metastatic disease (MD) groups. We analyzed the conversion rate and the value of the immunophenotype of the primary tumour and the relapse as a prognostic factor for relapse-free survival (RFS), progression-free survival (PFS) and overall survival (OS). RESULTS: The conversion rate was 34.8% for Ki-67, 20% for ER, 20% for PR, and 15.6% for HER2. For the LR group, the RFS was 71.9 months and the OS was 141.6 months, without statistical differences according to the immunophenotype of the primary or the relapsed biopsy. For the MD group, the PFS was 20.8 months. According to immunophenotype of the relapse, the PFS were ER+ 24.7 months vs. ER- 9.3 months; PR+ 25.1 months vs. PR- 12.7 months without statistical differences according to HER2 or Ki67. The OS for MD group was 54.4 months without statistical differences according to immunophenotype. CONCLUSION: The characteristics of breast cancer can change over the time. Variations of the ER or PR status in MD group have prognostic value for PFS. To perform a biopsy of relapses is warranted in order to establish the prognostic of the current disease, and probably a more accurate treatment.


Assuntos
Neoplasias da Mama/mortalidade , Antígeno Ki-67/metabolismo , Recidiva Local de Neoplasia/mortalidade , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Adulto , Idoso , Neoplasias da Mama/genética , Feminino , Humanos , Imunofenotipagem , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/genética , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
4.
J Gastroenterol Hepatol ; 33(4): 792-799, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29156509

RESUMO

Exosomes are extracellular microvesicles released from cells, which are involved in many biological and pathological processes, mainly because of their role in intercellular communication. Exosomes derived from colorectal cancer (CRC) cells are related to oncogenesis, tumor cell survival, chemo-resistance, and metastasis. The role of the exosomes in these processes involves the transfer of proteins, RNAs, or mutant versions of proto-oncogenes to the target cells. In recent years, great efforts have been made to identify useful biomarkers in CRC exosomes for diagnosis, prediction of prognosis, and treatment response. This review focuses on recent studies on CRC exosomes, considering isolation, cargo, biomarkers, and the effects of exosomes on the development and progression of CRC, including resistance to antitumor therapy.


Assuntos
Neoplasias Colorretais/patologia , Exossomos/fisiologia , Biomarcadores Tumorais , Carcinogênese , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Progressão da Doença , Resistencia a Medicamentos Antineoplásicos , Humanos , Mutação , Proteínas de Neoplasias/metabolismo , Prognóstico , Transporte Proteico , Proto-Oncogenes/genética , RNA Neoplásico/metabolismo
5.
J Nat Prod ; 80(2): 308-318, 2017 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-28121430

RESUMO

The in vitro antiproliferative activities of some taiwaniaquinoids and related compounds with functionalized A, B, or C rings against human breast (MCF-7), colon (T-84), and lung (A-549) tumor cell lines were assayed. The most potent compounds, 16, 27, and 36, were more effective than the naturally occurring taiwaniaquinones A (4) and F (5) in all three cell lines. The structure-activity relationship study of these new taiwaniaquinoids highlighted the correlation between the bromo substituent and the antiproliferative activity, especially in MCF-7 cells. These findings indicate that some of the taiwaniaquinoids might be useful as cytostatic agents against breast, colon, and lung cancer cell lines.


Assuntos
Antineoplásicos/farmacologia , Terpenos/farmacologia , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Células MCF-7 , Estrutura Molecular , Estereoisomerismo , Taiwan , Terpenos/química
6.
J Nat Prod ; 78(5): 1026-36, 2015 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-25906329

RESUMO

The first enantiospecific syntheses of neopetrosiquinones A (6) and B (7), two merosesquiterpenes isolated from the deep-water sponge Neopetrosia cf. proxima, from the labdane diterpene trans-communic acid (10) have been achieved. A key step of the synthetic sequence is the simultaneous aromatization of the C ring and the benzylic oxidation on C-7 of an advanced intermediate, mediated by the oxygen-DDQ system. The in vitro antiproliferative activities of neopetrosiquinone B (7) and of the synthetic intermediates 8 and 9 against human breast (MCF-7), lung (A-549), and colon (T-84) tumor cell lines have been assayed. The most potent was compound 9 (IC50 = 4.1 µM), which was twice as active as natural compound 7 (IC50 = 8.3 µM) against A-549 cells. In addition, the treatment with these compounds resulted in an induction of apoptosis. These findings indicate that the terpene benzoquinones reported here might be potentially useful as anticancer agents.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Benzoquinonas/farmacologia , Diterpenos/química , Sesquiterpenos/síntese química , Sesquiterpenos/farmacologia , Animais , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Benzoquinonas/química , Proliferação de Células/efeitos dos fármacos , Óxidos N-Cíclicos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Células MCF-7 , Biologia Marinha , Mercaptoetanol/análogos & derivados , Estrutura Molecular , Poríferos/química , Sesquiterpenos/isolamento & purificação , Estereoisomerismo , Relação Estrutura-Atividade
7.
J Mammary Gland Biol Neoplasia ; 19(3-4): 303-13, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26130410

RESUMO

Exosomes are small extracellular vesicles secreted to the extracellular environment by several cell types, including tumor cells. It has been demonstrated that exosomes have an important role in intercellular communication, but they have recently been implicated in various tumor processes, including the oncogenic transformation of cells in the tumor microenvironment, tumor drug resistance, and the transport of tumor factors. Tumors appear to use exosomes to dialogue with and transform neighboring cells to create an ideal environment for their growth and expansion. On the other hand, the structure and function of exosomes may make them useful in cancer diagnosis and prognosis, because they contain molecules that could serve as biomarkers, including oncogenes, miRNAs, and certain proteins. They have the ability to travel via body fluids, from which they could be isolated and used to transport drugs to specific targets. This review aims to provide an update on the role of exosomes derived from breast cancer cells.


Assuntos
Neoplasias da Mama/fisiopatologia , Neoplasias da Mama/ultraestrutura , Comunicação Celular , Transformação Celular Neoplásica , Resistencia a Medicamentos Antineoplásicos , Exossomos/fisiologia , Biomarcadores Tumorais , Neoplasias da Mama/patologia , Exossomos/química , Feminino , Humanos , Metástase Neoplásica , Microambiente Tumoral
8.
Eur J Clin Invest ; 44(7): 678-87, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24766664

RESUMO

BACKGROUND: The cancer stem cell (CSC) hypothesis on the origin of cancer has recently gained considerable support. CSCs are tumour cells with the capacity for self-renewal and differentiation that direct the origin and progression of the disease and may be responsible for relapse, metastasis and treatment failures. DESIGN: This article reviews breast CSCs (BCSCs) phenotyping, clinical implications and clinical trials focused on BCSCs in breast cancer. Relevant studies were found through PubMed and Clinicaltrials.gov databases. RESULTS: Cancer stem cells are identified and isolated using membrane and cell activity markers; in the case of BCSCs, these are CD44(+) /CD24(low/-) and show aldehyde dehydrogenase activity, alongside their capacity to grow and form mammospheres. The presence of stem cell properties is associated with a worse outcome. Hence, these cells have important clinical implications, and elucidation of the mechanisms underlying their activity will allow the development of novel effective therapies and diagnostic instruments, improving the prognosis of these patients. CONCLUSIONS: Standard treatments are directed against the tumour mass and do not eliminate CSCs. There is therefore a need for specific anti-CSC therapies, and numerous authors are investigating new targets to this end, as reported in this review. It is also necessary for clinical trials to be undertaken to allow this new knowledge to be applied in the clinical setting. However, there have been few trials on anti-BCSCs therapies to date.


Assuntos
Neoplasias da Mama/patologia , Células-Tronco Neoplásicas/fisiologia , Aldeído Desidrogenase/metabolismo , Antígenos de Neoplasias/metabolismo , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/enzimologia , Neoplasias da Mama/terapia , Antígeno CD24/metabolismo , Ensaios Clínicos como Assunto , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Receptores de Hialuronatos/metabolismo , Recidiva Local de Neoplasia/patologia , Células-Tronco Neoplásicas/enzimologia , Fenótipo
9.
J Assist Reprod Genet ; 31(12): 1621-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25267163

RESUMO

PURPOSE: According to the latest ART report for Europe, about 13% of pregnancies after frozen embryo transfer are multiple. Our objective was to analyse the impact on the multiple pregnancy rate of two eSFET (elective single frozen embryo transfers) versus a DFET (double frozen embryo transfer) in women aged under 38 years, who had not achieved pregnancy in their fresh transfer and who had at least two vitrified embryos of A/B quality. METHODS: This study was conducted from January 2010 to June 2013 at a public hospital. The couples were divided into three groups. Group DFET: the first cryotransfer of two embryos (105 women); cSFET group: the only cryotransfer of a single vitrified embryo (60 women); eSFET group, individually vitrified embryos: 20 patients included in a clinical trial of single-embryo fresh and frozen transfer and 21 patients who chose to receive eSFET. RESULTS: The clinical pregnancy rate was 38.1% in the DET group and the cumulative clinical pregnancy rate was 43.3% in the eSFET group. There were no significant differences between the DFET and eSFET groups (30.0 vs 34.1%) in cumulative live birth delivery rate. The rate of multiple pregnancies varied significantly between the DFET and eSFET groups (32.5 vs 0%, p < 0.05). CONCLUSIONS: For good-prognosis women aged under 38 years, taking embryo quality as a criterion for inclusion, an eSFET policy can be applied, achieving acceptable cumulative clinical pregnancy and live birth rates and reducing multiple pregnancy rates.


Assuntos
Coeficiente de Natalidade , Criopreservação , Fertilização in vitro , Vitrificação , Adulto , Fase de Clivagem do Zigoto , Estudos de Coortes , Feminino , Humanos , Gravidez , Taxa de Gravidez , Gravidez Múltipla/fisiologia , Transferência de Embrião Único
10.
Clin Transl Oncol ; 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38771533

RESUMO

PURPOSE: HER2 overexpression in breast cancer correlates with poor outcomes. The incorporation of Trastuzumab into the treatment regimen has notably improved patient prognoses. However, cardiotoxicity emerges in approximately 20% of patients treated with the drug. This study aims to investigate the association between the HER2 655 A > G polymorphism, Trastuzumab-induced cardiotoxicity, and patient survival. METHODS: The study involved 88 patients treated with Trastuzumab. Cardiotoxicity, defined as a reduction in left ventricular ejection fraction (LVEF) from baseline or the emergence of clinical signs of congestive heart failure, was identified during treatment follow-up. Genotyping of HER2 655 A > G employed TaqMan SNP technology. RESULTS: Genotype frequencies of HER2/neu 655 (53 AA, 32 AG, and 3 GG) were consistent with Hardy-Weinberg equilibrium. No significant differences were observed in mean baseline LVEF between patients who developed cardiotoxicity and those who did not. Within these groups, neither AA nor AG genotypes showed an association with changes in mean baseline or reduced LVEF levels. Logistic regression analysis, adjusted for hormonal status and anthracycline treatment, revealed that AG genotype carriers face a significantly higher risk of cardiotoxicity compared to AA carriers (OR = 4.42; p = 0.037). No association was found between the HER2/neu 655 A > G polymorphism and disease-free or overall survival, regardless of whether the data was adjusted for stage or not. CONCLUSION: HER2 655 A > G polymorphism is significantly linked to an increased risk of Trastuzumab-induced cardiotoxicity but does not correlate with variations in disease-free survival or overall survival rates.

11.
Breast ; 69: 342-348, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37011481

RESUMO

PURPOSE: Tamoxifen is a drug used for hormone receptor-positive breast cancers, primarily metabolised by the CYP2D6 enzyme into active metabolites such as endoxifen. CYP2D6 displays varying degrees of activity depending on its genotype. This study aims to analyse the effect of an early increase in tamoxifen dose in poor metabolisers (PM) on survival. METHODS: We enrolled 220 patients diagnosed with breast cancer who were treated with tamoxifen. CYP2D6 polymorphisms were determined, and the phenotype was estimated according to the Clinical Pharmacogenetics Implementation Consortium. Disease-free survival (DFS) and overall survival (OS) were analysed considering the entire patient group, and a subgroup of 110 patients selected by Propensity Score Matching (PSM). All women were treated with 20 mg/day of tamoxifen for 5 years, except PM, who initially received 20 mg/day for 4 months, followed by 40 mg/day for 4 months and 60 mg/day for 4 months before returning to the standard dose of 20 mg/day until completing 5 years of treatment. RESULTS: The analysis of the influence of CYP2D6 polymorphisms in the complete group and in the PSM subgroup revealed no significant differences for DFS or OS. Furthermore, DFS and OS were analysed in relation to various covariates such as age, histological grade, nodal status, tumour size, HER-2, Ki-67, chemotherapy, and radiotherapy. Only age, histological grade, nodal status, and chemotherapy treatment demonstrated statistical significance. CONCLUSION: An early increase in tamoxifen dose in PM patients is not associated with survival differences among CYP2D6 phenotypes.


Assuntos
Neoplasias da Mama , Feminino , Humanos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Citocromo P-450 CYP2D6/genética , Pontuação de Propensão , Antineoplásicos Hormonais/uso terapêutico , Resultado do Tratamento , Tamoxifeno/uso terapêutico , Genótipo
12.
Biomed Pharmacother ; 168: 115791, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37924793

RESUMO

Taiwaniaquinoids are a unique family of diterpenoids predominantly isolated from Taiwania cryptomerioides Hayata. Previously, we evaluated the antiproliferative effect of several synthetic taiwaniaquinoids against human lung (A-549), colon (T-84), and breast (MCF-7) tumor cell lines. Herein, we report the in vitro and in vivo antitumor activity of the most potent compounds. Their cytotoxic activity against healthy peripheral blood mononuclear cells (PBMCs) has also been examined. We underscore the limited toxicity of compound C36 in PBMCs and demonstrate that it exerts its antitumor effect in MCF-7 cells (IC50 = 1.8 µM) by triggering an increase in reactive oxygen species, increasing the cell population in the sub-G1 phase of the cell cycle (90 %), and ultimately activating apoptotic (49.6 %) rather than autophagic processes. Western blot results suggested that the underlying mechanism of the C36 apoptotic effects was linked to caspase 9 activation and a rise in the Bax/Bcl-2 ratio. In vivo analyses showed normal behavior and hematological parameters in C57BL/6 mice post C36 treatment. Moreover, no significant impact was observed on the biochemical parameters of these animals, indicating that C36 did not induce liver toxicity. Furthermore, C36 demonstrated a significant reduction in tumor growth in immune-competent C57BL/6 mice implanted with E0771 mouse mammary tumor cells, effectively improving survival rates. These findings position taiwaniaquinoids, particularly compound C36, as promising therapeutic candidates for human breast cancer.


Assuntos
Antineoplásicos , Neoplasias da Mama , Animais , Humanos , Camundongos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Leucócitos Mononucleares/metabolismo , Apoptose , Ensaios de Seleção de Medicamentos Antitumorais , Camundongos Endogâmicos C57BL , Linhagem Celular Tumoral , Células MCF-7 , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Antineoplásicos/química , Proliferação de Células
13.
J Transl Med ; 10: 250, 2012 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-23245659

RESUMO

BACKGROUND: The CD133 antigen is a marker of radio- and chemo-resistant stem cell populations in glioblastoma (GBM). The O6-methylguanine DNA methyltransferase (MGMT) enzyme is related with temozolomide (TMZ) resistance. Our propose is to analyze the prognostic significance of the CD133 antigen and promoter methylation and protein expression of MGMT in a homogenous group of GBM patients uniformly treated with radiotherapy and TMZ. The possible connection between these GBM markers was also investigated. METHODS: Seventy-eight patients with GBM treated with radiotherapy combined with concomitant and adjuvant TMZ were analyzed for MGMT and CD133. MGMT gene promoter methylation was determined by methylation-specific polymerase chain reaction after bisulfite treatment. MGMT and CD133 expression was assessed immunohistochemically using an automatic quantification system. Overall and progression-free survival was calculated according to the Kaplan-Meier method. RESULTS: The MGMT gene promoter was found to be methylated in 34 patients (44.7%) and unmethylated in 42 patients (55.3%). A significant correlation was observed between MGMT promoter methylation and patients' survival. Among the unmethylated tumors, 52.4% showed low expression of MGMT and 47.6% showed high-expression. Among methylated tumors, 58.8% showed low-expression of MGMT and 41.2% showed high-expression. No correlation was found between MGMT promoter methylation and MGMT expression, or MGMT expression and survival. In contrast with recent results, CD133 expression was not a predictive marker in GBM patients. Analyses of possible correlation between CD133 expression and MGMT protein expression or MGMT promoter methylation were negative. CONCLUSIONS: Our results support the hypothesis that MGMT promoter methylation status but not MGMT expression may be a predictive biomarker in the treatment of patients with GBM. In addition, CD133 should not be used for prognostic evaluation of these patients. Future studies will be necessary to determine its clinical utility.


Assuntos
Antígenos CD/metabolismo , Metilação de DNA/genética , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Dacarbazina/análogos & derivados , Glioblastoma/tratamento farmacológico , Glioblastoma/radioterapia , Glicoproteínas/metabolismo , Peptídeos/metabolismo , Regiões Promotoras Genéticas , Proteínas Supressoras de Tumor/genética , Antígeno AC133 , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/radioterapia , Dacarbazina/uso terapêutico , Intervalo Livre de Doença , Feminino , Glioblastoma/genética , Glioblastoma/patologia , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Reação em Cadeia da Polimerase , Prognóstico , Temozolomida , Resultado do Tratamento , Adulto Jovem
14.
Cytotherapy ; 13(2): 193-200, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20662611

RESUMO

BACKGROUND AIMS: Diabetes type I is an autoimmune disease characterized by the destruction of pancreatic insulin-producing (beta-) cells and resulting in external insulin dependence for life. Islet transplantation represents a potential treatment for diabetes but there is currently a shortage of suitable organs donors. To augment the supply of donors, different strategies are required to provide a potential source of beta-cells. These sources include embryonic and adult stem cells as well as differentiated cell types. The main goal of this study was to induce the transdifferentiation (or conversion of one type cell to another) of human hepatoma cells (HepG2 cells) to insulin-expressing cells based on the exposure of HepG2 cells to an extract of rat insulinoma cells (RIN). METHODS: HepG2 cells were first transiently permeabilized with Streptolysin O and then exposed to a cell extract obtained from RIN cells. Following transient exposure to the RIN extract, the HepG2 cells were cultured for 3 weeks. RESULTS: Acquisition of the insulin-producing cell phenotype was determined on the basis of (i) morphologic and (ii) ultrastructural observations, (iii) immunologic detection and (iv) reverse transcription (RT)-polymerase chain reaction (PCR) analysis. CONCLUSIONS: This study supports the use of cell extract as a feasible method for achieve transdifferentiation of hepatic cells to insulin-producing cells.


Assuntos
Transdiferenciação Celular , Células Hep G2/citologia , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/ultraestrutura , Insulina/biossíntese , Insulinoma , Animais , Proteínas de Bactérias , Extratos Celulares/farmacologia , Células Cultivadas , Imunofluorescência , Expressão Gênica , Hepatócitos/citologia , Hepatócitos/metabolismo , Humanos , Microscopia Eletrônica de Transmissão , Permeabilidade , Fenótipo , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estreptolisinas
15.
Cell Biol Int ; 35(4): 373-9, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21413928

RESUMO

Cell therapy is based on the replacement of damaged cells in order to restore injured tissues. The first consideration is that an abundant source of cells is needed; second, these cells should be immunologically compatible with the guest and third, there should be no real threat of these cells undergoing malignant transformation in the future. Given these requirements, already differentiated adult cells or adult stem cells obtained from the body of the patient appear to be the ideal candidates to meet all of these demands. The utilization of somatic cells also avoids numerous ethical and political drawbacks and concerns. Transdifferentiation is the phenomenon by which an adult differentiated cell switches to another differentiated cell. This paper reviews the importance of transdifferentiation, discussing the cells that are suitable for this process and the methods currently employed to induce the change in cell type.


Assuntos
Células-Tronco Adultas/citologia , Transdiferenciação Celular , Animais , Técnicas de Cultura de Células/métodos , Terapia Baseada em Transplante de Células e Tecidos , Humanos , Transplante de Células-Tronco
16.
Int J Mol Sci ; 12(5): 3303-21, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21686186

RESUMO

Nanotechnology, along with related concepts such as nanomaterials, nanostructures and nanoparticles, has become a priority area for scientific research and technological development. Nanotechnology, i.e., the creation and utilization of materials and devices at nanometer scale, already has multiple applications in electronics and other fields. However, the greatest expectations are for its application in biotechnology and health, with the direct impact these could have on the quality of health in future societies. The emerging discipline of nanomedicine brings nanotechnology and medicine together in order to develop novel therapies and improve existing treatments. In nanomedicine, atoms and molecules are manipulated to produce nanostructures of the same size as biomolecules for interaction with human cells. This procedure offers a range of new solutions for diagnoses and "smart" treatments by stimulating the body's own repair mechanisms. It will enhance the early diagnosis and treatment of diseases such as cancer, diabetes, Alzheimer's, Parkinson's and cardiovascular diseases. Preventive medicine may then become a reality.


Assuntos
Nanomedicina/tendências , Técnicas Biossensoriais , Dendrímeros/química , Sistemas de Liberação de Medicamentos , Ouro/química , Dispositivos Lab-On-A-Chip , Lipossomos , Nanopartículas Metálicas/química , Micelas , Nanomedicina/métodos , Nanoestruturas/química , Pontos Quânticos/química , Medicina Regenerativa/métodos , Medicina Regenerativa/tendências
17.
Cytotherapy ; 12(3): 332-7, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20230311

RESUMO

BACKGROUND AIMS: The goal was to induce the transdifferentiation (or conversion) of human adipose-derived stem cells to cardiomyocytes using an intracellular extract obtained from adult human heart tissue. METHODS: Human adult stem cells from lipoaspirates were transiently permeabilized, exposed to human atrial extracts and allowed to recover in culture. RESULTS: After 21 days, the cells acquired a cardiomyocyte phenotype, as demonstrated by morphologic changes (appearance of binucleate, striated cells and branching fibers), immunofluorescence detection of cardiac-specific markers (connexin-43, sarcomeric alpha-actinin, cardiac troponin I and T, and desmin) and the presence of cardiomyocyte-related genes analyzed by reverse transcription-polymerase chain reaction (cardiac myosin light chain 1, alpha-cardiac actin, cardiac troponin T and cardiac beta-myosin). CONCLUSIONS: We have demonstrated for the first time that adult cardiomyocytes obtained from human donors retain the capacity to induce cardiomyocyte differentiation of mesenchymal stromal cells. The use of autologous extracts for reprogramming adult stem cells may have potential therapeutic implications for treating heart disease.


Assuntos
Células-Tronco Adultas/fisiologia , Diferenciação Celular/fisiologia , Miocárdio , Miócitos Cardíacos/fisiologia , Tecido Adiposo/citologia , Adulto , Células-Tronco Adultas/citologia , Biomarcadores/metabolismo , Linhagem da Célula , Transdiferenciação Celular , Células Cultivadas , Átrios do Coração/citologia , Humanos , Miocárdio/citologia , Miocárdio/metabolismo , Miócitos Cardíacos/citologia
18.
Cells Tissues Organs ; 191(6): 478-88, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20090304

RESUMO

Nucleotides (NT) and nucleosides (NS) play a key role in gastrointestinal development and in enterocyte healing after tissue damage. Exogenous NT and NS may therefore represent a novel therapy for maintaining gastrointestinal tract integrity. An exogenous NS mixture of thymidine, cytidine, guanosine and inosine (T-CGI) increases the proliferation rate of rat intestinal epithelial cell line 6 (IEC-6) cells, while a mixture of uridine, cytidine, guanosine and inosine (U-CGI) reduces IEC-6 proliferation independently of necrosis or apoptosis. This study aimed to analyze the effects of exogenous NS on IEC-6 differentiation under proliferation and differentiation conditions. To this end, IEC-6 cells were treated with NS T-CGI and NS U-CGI mixtures under low- and high-density conditions. Enterocyte differentiation was also assessed by flow cytometry, Western blotting, and light, fluorescence and transmission electron microscopy. Under proliferative conditions, villin expression was reduced in all cases, but NS-treated cells showed twofold the expression observed in NS-free cultures (controls) and more frequently showed characteristics of mature enterocytes. When cells were grown after confluence, villin expression, total protein production and morphology of NS-treated cultures were more differentiated compared with the control group. Our results demonstrate that T-CGI and U-CGI mixtures promote IEC-6 cell differentiation, with no significant differences between them. Unlike previous authors, we obtained this effect in cultures without an exogenous extracellular matrix such as Matrigel, reducing the variability among independent assays.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Células Epiteliais/citologia , Intestinos/citologia , Nucleosídeos/farmacologia , Animais , Western Blotting , Linhagem Celular , Citidina/farmacologia , Células Epiteliais/ultraestrutura , Guanosina/farmacologia , Inosina/farmacologia , Microscopia , Microscopia Eletrônica de Transmissão , Ratos , Uridina/farmacologia
19.
Cell Biol Int ; 34(9): 917-24, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20522021

RESUMO

Adult stem cells are becoming the best option for regenerative medicine because they have low tumourigenic potential and permit autologous transplantation, even without in vitro culture. Our objectives were to evaluate the effects of exogenous nucleosides on the proliferation of hASCs (human adipose-derived stem cells), with or without co-treatment with 5-aza (5-azacytidine), and to analyse the expression of lamin A/C during cardiomyocyte differentiation of these cells. We isolated hASCs from human lipoaspirates that were positive for mesenchymal stem cell markers. We found that 5-aza induces a dose-dependent inhibition of hASC proliferation [IC50 (inhibitory concentration 50): 5.37 microM], whereas exogenous nucleosides significantly promote the proliferation of hASCs and partially revert the antiproliferative effect of the drug. Multipotentiality of isolated hASCs was confirmed by adipogenic, osteogenic and cardiomyogenic induction. 5-Aza-induced cells expressed cardiac troponins I and T and myosin light chain 2, myocardial markers that were directly correlated with lamin A/C expression. Our results support the importance of the nucleoside supplementation of media to improve conditions for the expansion and maintenance of hASCs in culture. In addition, the quantification of lamin A/C expression appears to be a good marker for the characterization of cardiomyocyte differentiation of stem cells that has rarely been used.


Assuntos
Tecido Adiposo/citologia , Nucleosídeos/farmacologia , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , Azacitidina/farmacologia , Biomarcadores/metabolismo , Adesão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Lamina Tipo A/metabolismo , Miocárdio/metabolismo , Células-Tronco/metabolismo
20.
Breast ; 54: 106-113, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32977298

RESUMO

BACKGROUND: Trastuzumab is a drug used in HER2-positive breast cancer that increases patient survival. Due to cardiotoxicity is the most important side effect of trastuzumab treatment, cardiac monitoring should be a priority. The purpose of this study is to evaluate plasma NT-proBNP level and major cardiovascular risk factors as possible early predictors of trastuzumab-induced cardiotoxicity in HER2-positive breast cancer patients. METHODS: We conducted a retrospective observational study involving 66 patients with HER2-positive breast cancer treated with trastuzumab. Left ventricle ejection fraction (LVEF), NT-proBNP values, and the history of cardiovascular risk factors were collected. Cardiotoxicity was diagnosed considering a decrease of the LVEF from baseline or clinical manifestation of congestive heart failure. NT-proBNP cut-off points were considered to establish normal or abnormal values according to patient age. RESULTS: 27.3% of the patients suffered cardiotoxicity during trastuzumab treatment. Most cases were diagnosed due to the appearance of cardiac symptomatology (66.7%). Logistic regression analysis showed a significant association of diabetes mellitus (OR 5.9, 95% CI 1.2-28.5, p = 0.028) and high NT-proBNP levels (OR 22.0, 95% CI 5.7-85.4, p < 0.0001) with the development of trastuzumab-induced cardiotoxicity. CONCLUSION: NT-proBNP levels above the upper limit of the normal range adjusted to age or diabetes mellitus seem to be associated with a higher risk of developing cardiotoxicity. However, some limitations of the present study make necessary further studies aimed to clarify whether NT-proBNP and diabetes-associated markers determinations can be useful in the monitoring of cardiotoxicity risk in breast cancer patients undergoing trastuzumab therapy.


Assuntos
Antineoplásicos/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Insuficiência Cardíaca/diagnóstico , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Trastuzumab/efeitos adversos , Adulto , Idoso , Biomarcadores Farmacológicos/análise , Neoplasias da Mama/sangue , Cardiotoxicidade/diagnóstico , Diabetes Mellitus/sangue , Monitoramento de Medicamentos , Feminino , Fatores de Risco de Doenças Cardíacas , Insuficiência Cardíaca/induzido quimicamente , Humanos , Modelos Logísticos , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Receptor ErbB-2/metabolismo , Estudos Retrospectivos , Volume Sistólico/efeitos dos fármacos , Função Ventricular Esquerda/efeitos dos fármacos
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