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1.
Biomed Pharmacother ; 153: 113348, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35820315

RESUMO

Pequi oil is extracted from the fruit of a Brazilian native plant (Caryocar brasiliense Camb) that contains some molecules with anticancer potential. Due to its hydrophobic property, the administration of pequi oil associated with nanoemulsion systems represents a successful strategy to improve oil bioavailability. Breast cancer is the most frequent type of cancer among women and conventional therapies used are frequently associated with several side effects. Thus, the aim of this study was to investigate the effects of pequi oil-based nanoemulsion (PeNE) on triple-negative breast cancer cells (4T1), in vitro. PeNE presented a dose- and time-dependent cytotoxic effect with lower IC50 than free pequi oil after 48 h of exposure (p < 0.001). At 180 µg/mL, PeNE demonstrated numerous cell alterations, when compared to free pequi oil, such as morphological alterations, reduction in cell proliferation and total cell number, damage to plasmatic membrane, induction of lysosomal membrane permeability and depolarization of mitochondrial membrane, alteration of intracellular ROS production and calcium level, and increase in phosphatidylserine exposure. Taken together, the results suggest an interesting induction of cell death mechanisms involving a combined action of factors that impair nucleus, mitochondria, lysosome, and ER function. In addition, more pronounced effects were observed in cells treated by PeNE at 180 µg/mL when compared to free pequi oil, thereby reinforcing the advantages of using nanometric platforms. These promising results highlight the use of PeNE as a potential complementary therapeutic approach to be employed along with conventional treatments against breast cancer in the future.


Assuntos
Ericales , Malpighiales , Neoplasias de Mama Triplo Negativas , Proliferação de Células , Ericales/química , Feminino , Humanos , Organelas , Óleos de Plantas/química , Óleos de Plantas/farmacologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico
2.
BMC Biotechnol ; 10: 19, 2010 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-20196841

RESUMO

BACKGROUND: Theracyte is a polytetrafluoroethylene membrane macroencapsulation system designed to induce neovascularization at the tissue interface, protecting the cells from host's immune rejection, thereby circumventing the problem of limited half-life and variation in circulating levels. Endostatin is a potent inhibitor of angiogenesis and tumor growth. Continuous delivery of endostatin improves the efficacy and potency of the antitumoral therapy. The purpose of this study was to determine whether recombinant fibroblasts expressing endostatin encapsulated in Theracyte immunoisolation devices can be used for delivery of this therapeutic protein for treatment of mice bearing B16F10 melanoma and Ehrlich tumors. RESULTS: Mice were inoculated subcutaneously with melanoma (B16F10 cells) or Ehrlich tumor cells at the foot pads. Treatment began when tumor thickness had reached 0.5 mm, by subcutaneous implantation of 107 recombinant encapsulated or non-encapsulated endostatin producer cells. Similar melanoma growth inhibition was obtained for mice treated with encapsulated or non-encapsulated endostatin-expressing cells. The treatment of mice bearing melanoma tumor with encapsulated endostatin-expressing cells was decreased by 50.0%, whereas a decrease of 56.7% in tumor thickness was obtained for mice treated with non-encapsulated cells. Treatment of Ehrlich tumor-bearing mice with non-encapsulated endostatin-expressing cells reduced tumor thickness by 52.4%, whereas lower tumor growth inhibition was obtained for mice treated with encapsulated endostatin-expressing cells: 24.2%. Encapsulated endostatin-secreting fibroblasts failed to survive until the end of the treatment. However, endostatin release from the devices to the surrounding tissues was confirmed by immunostaining. Decrease in vascular structures, functional vessels and extension of the vascular area were observed in melanoma microenvironments. CONCLUSIONS: This study indicates that immunoisolation devices containing endostatin-expressing cells are effective for the inhibition of the growth of melanoma and Ehrlich tumors.Macroencapsulation of engineered cells is therefore a reliable platform for the refinement of innovative therapeutic strategies against tumors.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma de Ehrlich/terapia , Transplante de Células , Endostatinas/uso terapêutico , Melanoma Experimental/terapia , Inibidores da Angiogênese/uso terapêutico , Animais , Endostatinas/metabolismo , Fibroblastos/metabolismo , Implantes Experimentais , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Neovascularização Patológica/prevenção & controle
3.
Clin Endocrinol (Oxf) ; 67(6): 845-52, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17645576

RESUMO

OBJECTIVES: To evaluate body fat in nonobese women with prolactinoma treated with dopamine agonists, using whole body dual energy X-ray absorptiometry (DXA) and to correlate DXA results with biochemical data and clinical aspects of the prolactinoma. DESIGN, PATIENTS AND MEASUREMENTS: A cross-sectional study was performed in two University referral centres. Thirty-one nonobese premenopausal women with prolactinoma were subjected to DXA and blood analysis at clinical evaluation. They were compared with 21 control women of similar age and body mass index (BMI). RESULTS: Women with prolactinoma treated with dopamine agonists and controls had similar body fat percentages in all sites evaluated with DXA (arms, legs, trunk, android, gynoid and total body). Patients with normal PRL levels at study entry had lower body fat percentages in all sites. In the patient group, arm, leg, truncal, android, gynoid and total body fat were positively associated with PRL levels. CONCLUSION: Body fat percentage is similar in nonobese women with prolactinoma and in controls. The lower body fat content in patients with normal PRL levels is likely to be due to the metabolic effects of adequate dopamine receptor type 2 (DR2) activation as a result of regular dopamine agonist treatment. This finding reinforces the importance of the appropriate treatment with dopamine agonists in women with prolactinoma, which, besides normalizing PRL levels, reduces body fat content and the consequent risk of developing Metabolic Syndrome and its complications.


Assuntos
Tecido Adiposo/fisiologia , Agonistas de Dopamina/uso terapêutico , Obesidade/metabolismo , Prolactinoma/tratamento farmacológico , Prolactinoma/metabolismo , Absorciometria de Fóton , Adolescente , Adulto , Estudos Transversais , Feminino , Hormônio Foliculoestimulante/sangue , Hormônio do Crescimento/sangue , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Hormônio Luteinizante/sangue , Pessoa de Meia-Idade , Prolactina/sangue , Prolactinoma/sangue , Globulina de Ligação a Hormônio Sexual/metabolismo , Tireotropina/sangue , Adulto Jovem
4.
Genet Mol Res ; 4(2): 290-308, 2005 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-16110447

RESUMO

Annotation of the transcriptome of the dimorphic fungus Paracoccidioides brasiliensis has set the grounds for a global understanding of its metabolism in both mycelium and yeast forms. This fungus is able to use the main carbohydrate sources, including starch, and it can store reduced carbons in the form of glycogen and trehalose; these provide energy reserves that are relevant for metabolic adaptation, protection against stress and infectivity mechanisms. The glyoxylate cycle, which is also involved in pathogenicity, is present in this fungus. Classical pathways of lipid biosynthesis and degradation, including those of ketone body and sterol production, are well represented in the database of P. brasiliensis. It is able to synthesize de novo all nucleotides and amino acids, with the sole exception of asparagine, which was confirmed by the fungus growth in minimal medium. Sulfur metabolism, as well as the accessory synthetic pathways of vitamins and co-factors, are likely to exist in this fungus.


Assuntos
Etiquetas de Sequências Expressas/metabolismo , Regulação Fúngica da Expressão Gênica , Paracoccidioides/metabolismo , Transcrição Gênica , Aminoácidos/metabolismo , Metabolismo dos Carboidratos , Ácidos Graxos/metabolismo , Paracoccidioides/genética , Fosforilação , Purinas/metabolismo , Pirimidinas/metabolismo , Enxofre/metabolismo
5.
Cancer Lett ; 345(1): 27-38, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24333733

RESUMO

Kinins are generated within inflammatory tissue microenvironments, where they exert diverse functions, including cell proliferation, leukocyte activation, cell migration, endothelial cell activation and nociception. These pleiotropic functions depend on signaling through two cross talking receptors, the constitutively expressed kinin receptor 2 (B2R) and the inducible kinin receptor 1 (B1R). We have reviewed evidence, which supports the concept that kinin receptors, especially kinin receptor 1, are promising targets for cancer therapy, since (1) many tumor cells express aberrantly high levels of these receptors; (2) some cancers produce kinins and use them as autocrine factors to stimulate their growth; (3) activation of kinin receptors leads to activation of macrophages, dendritic cells and other cells from the tumor microenvironment; (4) kinins have pro-angiogenic properties; (5) kinin receptors have been implicated in cancer migration, invasion and metastasis; and (6) selective antagonists for either B1R or B2R have shown anti-proliferative, anti-inflammatory, anti-angiogenic and anti-migratory properties. The multiple cross talks between kinin receptors and renin-angiotensin system (RAS) as well as its implications for targeting KKS or RAS for the treatment of malignancies are also discussed. It is expected that B1R antagonists would interfere less with housekeeping functions and therefore would be attractive compounds to treat selected types of cancer. Reliable clinical studies are needed to establish the translatability of these data to human settings and the usefulness of kinin receptor antagonists.


Assuntos
Antagonistas de Receptor B1 da Bradicinina , Antagonistas de Receptor B2 da Bradicinina , Neoplasias/tratamento farmacológico , Receptor B1 da Bradicinina/metabolismo , Receptor B2 da Bradicinina/metabolismo , Animais , Humanos , Terapia de Alvo Molecular , Transdução de Sinais
6.
Br J Health Psychol ; 18(4): 858-73, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23410203

RESUMO

OBJECTIVES: The main goal of this study is to explore what is meant by "quality of care" (QoC) by both health professionals and patients. This research also intends to compare the perspectives of nurses, doctors and patients in order to understand whether these different actors share similar views on what represents QoC. DESIGN AND METHODS: A qualitative study was conducted. The study consisted in 44 semi-structured individual interviews (11 doctors; 23 nurses; 10 patients) and in three focus groups (20 participants: doctors, nurses, patients). Participants were doctors, nurses and patients from several Hospitals in Portugal. Data were analysed using content analysis methodology with MaxQDA software. RESULTS: The main content analysis' results revealed that all participants emphasize technical and interpersonal dimensions of QoC. Nevertheless, professionals stressed the availability of equipment and supplies and the conditions of health care indoor facilities. Patients focused more on their access to health services, namely the availability of health professionals, and on the health status outcome after care. In what the differences between doctors and nurses are concerned, the former tend to highlight the technical aspects of care more than the nurses, who tend to refer interpersonal aspects immediately. CONCLUSIONS: Although nowadays the importance of health care quality has become well-recognized, its definition is still complex. Given that specific aspects are more valued by certain groups than others, it is important to take in consideration all the stakeholder's perspectives when measuring QoC in order to continuously improve it in the 'real' settings.


Assuntos
Atitude do Pessoal de Saúde , Atitude Frente a Saúde , Corpo Clínico Hospitalar , Recursos Humanos de Enfermagem Hospitalar , Pacientes , Qualidade da Assistência à Saúde , Adulto , Idoso , Feminino , Grupos Focais , Humanos , Masculino , Pessoa de Meia-Idade , Portugal , Pesquisa Qualitativa
7.
Immunol Lett ; 125(2): 129-36, 2009 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-19573559

RESUMO

Strategies to minimize the immunogenicity and toxicity of murine anti-CD3 antibodies (e.g. OKT3) are of special interest for organ transplantation and for the treatment of autoimmune diseases. In the present work, we have developed two humanized anti-CD3 antibodies. These molecules were shown to bind to human CD3, though less efficiently, and display less mitogenic activity than OKT3. These results prompted us to investigate whether this reduced mitogenic potential was associated with the development of anti-inflammatory properties. Indeed, in peripheral blood mononuclear cells (PBMCs), the humanized antibody versions induced a predominantly anti-inflammatory cytokine profile, in contrast with the pro-inflammatory profile induced by OKT3. Neither OKT3 nor the humanized versions induced the expression of IL-4, IL-2 or TGF-beta. Both humanized antibodies induced significantly lower production of IFN-gamma and IL-5 and slightly higher production of IL-10 than OKT3. This immunomodulatory profile was most evident by the 80-fold higher ratio of IL-10/IFN-gamma production in PBMCs cultured in the presence of the humanized antibodies, compared to those stimulated with OKT3. Furthermore, these humanized anti-CD3 antibodies induced a late FOXP3 gene expression while OKT3 led to a more transient expression of FOXP3. Taken our results, we suggest that these humanized anti-CD3 antibodies may promote the development of T cells with immunoregulatory activity.


Assuntos
Doenças Autoimunes/terapia , Complexo CD3/imunologia , Fatores de Transcrição Forkhead/metabolismo , Rejeição de Enxerto/terapia , Imunoterapia , Linfócitos T/imunologia , Animais , Anticorpos Monoclonais , Doenças Autoimunes/imunologia , Células CHO , Proliferação de Células/efeitos dos fármacos , Cricetinae , Cricetulus , Citocinas/metabolismo , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/imunologia , Regulação da Expressão Gênica/efeitos dos fármacos , Engenharia Genética , Rejeição de Enxerto/imunologia , Humanos , Fragmentos de Imunoglobulinas/genética , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Muromonab-CD3/farmacologia , Transplante de Órgãos , Proteínas Recombinantes de Fusão , Linfócitos T/metabolismo , Linfócitos T/patologia
8.
Sex Transm Dis ; 30(9): 694-9, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12972792

RESUMO

BACKGROUND: Trichomoniasis is the most prevalent nonviral sexually transmitted disease in humans worldwide. In addition to its pathologic implications, trichomoniasis is a risk factor for the transmission of the HIV and is associated with reproductive complications in females. Diagnosis of the disease is problematic due to inadequate accuracy of current diagnostic methods. Recently developed DNA-based techniques for detection of Trichomonas vaginalis seem to be promising alternatives. GOAL: The goal of this study was to evaluate the accuracy of the Papanicolaou test for the diagnosis of trichomoniasis by comparing polymerase chain reaction (PCR) with other current diagnostic methods. STUDY DESIGN: A total of 1008 cervicovaginal swab specimens from a randomized population attending a gynecological service were analyzed in this study. In addition to current diagnostic methods, two sets of specific primers were used for PCR detection of T vaginalis in the cervicovaginal DNA samples, with a PCR quality control. Different examiners conducted PCR and Papanicolaou analyses in a double-blind trial. RESULTS: The prevalence of trichomoniasis in this population was 6%. A considerable number of diagnostic results of the Papanicolaou test were false negative or false positive. Compared with PCR, specificity of the Papanicolaou test was 97.6%, whereas sensitivity was only 60.7%. The positive predictive value of the Papanicolaou smear was 61.7%. These results suggest that irregularly shaped parasites without clearly defined nuclei and flagella and bacteria-induced focal cytolysis limit the ability of the Papanicolaou test to detect T vaginalis. CONCLUSION: The Papanicolaou test, the most readily available cytologic method for screening sexually transmitted pathogens and cellular abnormalities in most developing countries, is inadequate for the diagnosis of trichomoniasis due to its inherent limitations. However, PCR is a highly sensitive and specific test for the diagnosis of trichomoniasis.


Assuntos
DNA de Protozoário/análise , Teste de Papanicolaou , Reação em Cadeia da Polimerase/normas , Vaginite por Trichomonas/diagnóstico , Vaginite por Trichomonas/epidemiologia , Trichomonas vaginalis/genética , Esfregaço Vaginal/normas , Adulto , Animais , Brasil/epidemiologia , Primers do DNA , Método Duplo-Cego , Reações Falso-Negativas , Feminino , Humanos , Valor Preditivo dos Testes , Prevalência , Sensibilidade e Especificidade , Trichomonas vaginalis/isolamento & purificação
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