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1.
Sci Rep ; 12(1): 14815, 2022 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-36045277

RESUMEN

Luciferin biosynthetic origin and alternative biological functions during the evolution of beetles remain unknown. We have set up a bioluminescent sensing method for luciferin synthesis from cysteine and benzoquinone using E. coli and Pichia pastoris expressing the bright Amydetes vivianii firefly and P. termitilluminans click beetle luciferases. In the presence of D-cysteine and benzoquinone, intense bioluminescence is quickly produced, indicating the expected formation of D-luciferin. Starting with L-cysteine and benzoquinone, the bioluminescence is weaker and delayed, indicating that bacteria produce L-luciferin, and then racemize it to D-luciferin in the presence of endogenous esterases, CoA and luciferase. In bacteria the p-benzoquinone toxicity (IC50 ~ 25 µM) is considerably reduced in the presence of cysteine, maintaining cell viability at 3.6 mM p-benzoquinone concomitantly with the formation of luciferin. Transcriptional analysis showed the presence of gene products involved with the sclerotization/tanning in the photogenic tissues, suggesting a possible link between these pathways and bioluminescence. The lack of two enzymes involved with the last steps of these pathways, indicate the possible accumulation of toxic quinone intermediates in the lanterns. These results and the abundance of cysteine producing enzymes suggest that luciferin first appeared as a detoxification byproduct of cysteine reaction with accumulated toxic quinone intermediates during the evolution of sclerotization/tanning in Coleoptera.


Asunto(s)
Escarabajos , Luciferina de Luciérnaga , Luciferasas de Luciérnaga , Quinonas , Animales , Escarabajos/metabolismo , Cisteína/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Luciérnagas/genética , Luciferina de Luciérnaga/metabolismo , Luciferasas/genética , Luciferasas/metabolismo , Luciferasas de Luciérnaga/metabolismo , Luciferinas , Mediciones Luminiscentes , Quinonas/metabolismo , Saccharomycetales/metabolismo
2.
Nanotechnology ; 33(20)2022 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-35100566

RESUMEN

Short time treatment with reduced dosages of selol-loaded PLGA nanocapsules (NcSel) combined with magnetic hyperthermia (MHT) is evaluated in aged Erhlich tumor-bearing mice. Clinical, hematological, biochemical, genotoxic and histopathological parameters are assessed during 7 d treatment with NcSel and MHT, separately or combined. The time evolution of the tumor volume is successfully modeled using the logistic mathematical model. The combined therapy comprising NcSel and MHT is able to hinder primary tumor growth and a case of complete tumor remission is recorded. Moreover, no metastasis was diagnosed and the adverse effects are negligible. NcSel plus MHT may represent an effective and safe alternative to cancer control in aged patients. Future clinical trials are encouraged.


Asunto(s)
Neoplasias de la Mama/terapia , Hipertermia Inducida , Nanopartículas de Magnetita/uso terapéutico , Nanocápsulas/uso terapéutico , Compuestos de Selenio/uso terapéutico , Animales , Neoplasias de la Mama/patología , Carcinoma de Ehrlich/patología , Carcinoma de Ehrlich/terapia , Ciclo Celular/efectos de los fármacos , Terapia Combinada , Fragmentación del ADN/efectos de los fármacos , Femenino , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/ultraestructura , Ratones , Nanocápsulas/química , Nanocápsulas/ultraestructura , Compuestos de Selenio/química , Factores de Tiempo , Resultado del Tratamiento , Carga Tumoral/efectos de los fármacos
3.
Braz. arch. biol. technol ; 64: e21190387, 2021. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1153290

RESUMEN

HIGHLIGHTS Production of lipid nanoemulsions (<100 nm) of industrial interest with low energy demand. The antioxidant properties of babassu oil have been improved and the nanoemulsions are not cytotoxic. Babassu oil is a food and medicinal product. The nanoemulsion is strategic for the developed of new antioxidants phytotherapeutics.


Abstract Background: Babassu oil is an extract from a Brazilian native coconut (Orbignya phalerata Martius) and is used both as a food and a medicinal product. Methods: we produced two babassu oil nanoemulsions and evaluated them regarding their nanoscopic stability, antioxidant activity and cytotoxicity.The nanoemulsions were characterized by Dynamic Light Scattering, and their stability was investigated for 120 days. The antioxidant activity was assessed by Spectroscopy Electron Paramagnetic Resonance, and the cytotoxicity was assessed by a colorimetric method (MTT) with the NIH/3T3 cell lineage. Results: the results showed nanoemulsions with average hydrodynamic diameter lower than 100 nm (p(0.001).and a polydispersity index of less than 0.3 (p(0.001), indicating monodisperse systems and good stability at room temperature. The exposure of nanoemulsions at varying pH revealed that the isoelectric point was at 3.0, and the images obtained by Transmission Electron Microscopy showed spherical droplets with a size 27 nm. The antioxidant activity showed that the babassu nanoemulsions exposed to free radicals had a better response when compared to the oil free samples. The cell viability assays showed low toxicity of the formulation with viability over 92% (p(0.05). Conclusion: babassu oil nanoformulations showed low polydispersity and kinetic stability with effective antioxidant action. Therefore, they can be promising for application in the food industry or as antioxidant phytotherapeutics.


Asunto(s)
Aceite de Palma/química , Nanotecnología , Antioxidantes , Extractos Vegetales/química , Industria de Alimentos , Citotoxinas , Microscopía Electrónica de Transmisión , Emulsiones , Nanocompuestos
4.
Pensar Prát. (Online) ; 2317/04/2020. Tab
Artículo en Portugués | LILACS | ID: biblio-1141533

RESUMEN

O objetivo desta pesquisa foi analisar a concepção da dança como conteúdo da educação física escolar, expressa nos artigos publica - dos na Revista Brasileira de Ciências do Esporte (RBCE). Trata-se de pes- quisa bibliográfica em que foram analisados 10 artigos. Encontramos em maior abundância as concepções da dança como linguagem, linguagem simbólica ou forma de comunicação e maior incidência do referencial fenomenológico. Apontamos a necessidade de aprofundamentos sobre o tipo de sujeito que se quer formar a partir das concepções citadas. Por fim, fazemos a defesa do ensino da dança na escola a partir da concep - ção de formação omnilateral.


The objective of this research was to analyze the conception of dance as content of school physical education, expressed in the articles published in the Brazilian Journal of Sports Sciences (RBCE). It is a bibliographical research in which 10 articles were analyzed. We show in greater abundance the conceptions of dance as language, symbolic language or form of communication, and higher incidence of the phenomenological referential. We point out the need for deepening on the type of subject that one wants to form from the conceptions mentioned. Finally, we make the defense of the teaching of dance in the school from the conception of omnilateral formation.


El objetivo de esta investigación fue analizar la concepción de danza como contenido de la educación física escolar, expresa en los artículos publicados en la Revista Brasileña de Ciencias del Deporte (RBCE). Es una investigación bibliográfica en la cual fueron analizados 10 artículos. Evidenciamos en mayor abundancia las concepciones de danza como lenguaje, lenguaje simbólico o manera de comunicación y mayor incidencia del referencial fenomenológico. Aponemos la necesidad de profundizaciones sobre el tipo de sujeto que se quiere formar a partir de las concepciones citadas. Por último, hacemos la defensa de la enseñanza de la danza en la escuela a partir de la concepción de la formación omnilateral.


Asunto(s)
Humanos , Educación y Entrenamiento Físico , Instituciones Académicas , Baile/educación , Deportes , Enseñanza , Comunicación , Características Culturales , Educación
5.
Nutrition ; 60: 48-52, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30529186

RESUMEN

OBJECTIVES: The aim of the present study was to evaluate the association between sarcopenia, diagnosed by different muscle mass measurement techniques, with nutritional status and overall survival in patients with advanced cancer under palliative care. AIM: To investigate the association of sarcopenia, according to distinct muscle mass measurement methods, with nutritional status and overall survival (OS). METHODS: This observational and prospective study, including 334 patients, defined sarcopenia as reduced muscle mass and strength. Muscle mass was evaluated adopting 3 different methods, mid-upper arm muscle area (MUAMA), calf circumference (CC) and appendicular skeletal muscle mass (ASMI) described by Baumgartner (1998) and adjusted for height. Strength was defined using a handgrip dynamometer and OS was established based on a 90 days follow-up after inclusion date. Kaplan-Meier curves were conducted for survival analyzes and the association between sarcopenia and OS was evaluated by Cox regression model RESULTS: Prevalence of sarcopenia varied from 27-65% according to the method used to evaluate muscle mass. Malnutrition assessed by different parameters was significantly higher in patients with sarcopenia. Patients considered sarcopenic by MUAMA (43 versus 67 days, p<0.001), CC (44 versus 77 days, p<0.001) and ASMI (48 versus 75 days, p<0.001) had significantly lower OS compared to non-sarcopenic patients. Sarcopenia evaluated by MUAMA (HR, 1.57; 95% CI, 1.12-2.18) and CC (HR, 2.00; 95% CI, 1.45-2.76) showed a higher risk of mortality. CONCLUSION: Sarcopenia diagnosed by MUAMA and CC could predict mortality and CC proved to be the best prognostic method for estimating OS in patients with advanced cancer in palliative care.


Asunto(s)
Antropometría/métodos , Neoplasias/mortalidad , Estado Nutricional , Sarcopenia/diagnóstico , Sarcopenia/mortalidad , Anciano , Brazo/fisiopatología , Femenino , Fuerza de la Mano , Humanos , Estimación de Kaplan-Meier , Pierna/fisiopatología , Masculino , Desnutrición/etiología , Desnutrición/mortalidad , Persona de Mediana Edad , Fuerza Muscular , Músculo Esquelético/fisiopatología , Neoplasias/complicaciones , Neoplasias/terapia , Cuidados Paliativos/estadística & datos numéricos , Prevalencia , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Sarcopenia/etiología
6.
Photodiagnosis Photodyn Ther ; 20: 62-70, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28838760

RESUMEN

BACKGROUND: The development of nanocarriers is an important approach to increase the bioavailability of hydrophilic drugs in target cells. In this work, we evaluated the anti-tumorigenic mechanisms and efficacy of NanoALA, a novel nanoformulation of aminolevulic acid (ALA) based on poly(lactide-co-glycolide) (PLGA) nanocapsules designed for anticancer photodynamic therapy (PDT). METHODS: For this purpose, physicochemical characterization, prodrug incorporation kinetics, biocompatibility and photocytotoxicity tests, analysis of the cell death type and mitochondrial function, measurement of the intracellular reactive oxygen species production and DNA fragmentation were performed in murine mammary carcinoma (4T1) cells. RESULTS: NanoALA formulation, stable over a period of 90days following synthesis, presented hydrodynamic diameter of 220±8.7nm, zeta potential of -30.6mV and low value of polydispersity index (0.28). The biological assays indicated that the nanostructured product promotes greater ALA uptake by 4T1 cells and consequently more cytotoxicity in the PDT process. For the first time in the scientific literature, there is a therapeutic efficacy report of approximately 80%, after only 1h of incubation with 100µgmL-1 prodrug (0.6mM ALA equivalent). The mitochondria are probably the initial target of treatment, culminating in energy metabolism disorders and cell death by apoptosis. CONCLUSIONS: NanoALA emerges as a promising strategy for anticancer PDT. Besides being effective against a highly aggressive tumor cell line, the treatment may be economically advantageous because it allows a reduction in the dose and frequency of application compared to free ALA.


Asunto(s)
Ácido Aminolevulínico/administración & dosificación , Nanocápsulas/química , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/administración & dosificación , Animales , Apoptosis/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Femenino , Ácido Láctico , Potencial de la Membrana Mitocondrial , Ratones , Ácido Poliglicólico , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Especies Reactivas de Oxígeno/metabolismo
7.
J Photochem Photobiol B ; 166: 301-310, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28024281

RESUMEN

Melanoma is the most aggressive and lethal form of skin cancer, responsible for >80% of deaths. Standard treatments for late-stage melanoma usually present poor results, leading to life-threatening side effects and low overall survival. Thus, it is necessary to rethink treatment strategies and design new tools for the treatment of this disease. On that ground, we hereby report the use of acai oil in nanoemulsion (NanoA) as a novel photosensitizer for photodynamic therapy (PDT) used to treat melanoma in in vitro and in vivo experimental models. NIH/3T3 normal cells and B16F10 melanoma cell lines were treated with PDT and presented 85% cell death for melanoma cells, while maintaining high viability in normal cells. Flow cytometry indicated that cell death occurred by late apoptosis/necrosis. Tumor bearing C57BL/6 mice treated five times with PDT using acai oil in nanoemulsion showed tumor volume reduction of 82% in comparison to control/tumor group. Necrotic tissue per tumor area reached its highest value in PDT-treated mice, supporting PDT efficacy. Overall, acai oil in nanoemulsion was an effective photosensitizer, representing a promising source of new photosensitizing molecules for PDT treatment of melanoma, a tumor with an inherent tendency to be refractory for this type of therapy.


Asunto(s)
Emulsiones , Euterpe/química , Melanoma/tratamiento farmacológico , Fotoquimioterapia , Aceites de Plantas/uso terapéutico , Animales , Ratones , Ratones Endogámicos C57BL , Células 3T3 NIH , Nanotecnología
8.
J Biomed Nanotechnol ; 12(4): 689-99, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27301195

RESUMEN

The objective of this study was to investigate the activity of photodynamic therapy mediated by aluminum-chlorophthalocyanine contained in a polymeric nanostructured carrier composed by methyl vinyl ether-co-maleic anhydride (PVM/MA) against local subcutaneous breast cancer tumors and its effects against distant metastasis in a mouse tumor model. In our results, we observed a decrease in breast cancer tumor growth, prevention of distant lung metastases, and a significant increased survival in mice treated with photodynamic therapy. In addition to these results, we observed that tumor-bearing mice without treatment developed a significant extension of liver hematopoiesis that was significantly reduced in mice treated with photodynamic therapy. We hypothesized and showed that this reduction in (1) metastasis and (2) liver hematopoiesis may be related to the systemic activity of immature hematopoietic cells, specifically the myeloid-derived suppressor cells, which were suppressed in mice treated with photodynamic therapy. These cells produce a tolerogenic tumor environment that protects tumor tissues from immunological surveillance. Therefore, we suggest that photodynamic therapy could be employed in combination with other conventional therapies; such as surgery and radiotherapy, to improve the overall survival of patients diagnosed with breast cancer, as observed in our experimental resuIts.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Indoles/administración & dosificación , Neoplasias Pulmonares/prevención & control , Neoplasias Pulmonares/secundario , Nanocápsulas/química , Compuestos Organometálicos/administración & dosificación , Animales , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Neoplasias de la Mama/patología , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/efectos de la radiación , Femenino , Indoles/química , Neoplasias Pulmonares/patología , Maleatos/química , Ratones , Ratones Endogámicos BALB C , Nanocápsulas/administración & dosificación , Nanocápsulas/ultraestructura , Compuestos Organometálicos/química , Fármacos Fotosensibilizantes/administración & dosificación , Fármacos Fotosensibilizantes/química , Polietilenos/química , Resultado del Tratamiento
9.
Cell Adh Migr ; 5(1): 29-33, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-20935452

RESUMEN

Magnetic nanoparticles surface-covered with meso-2,3-dimercaptosuccinic acid (MNPs-DMSA) constitute a promising approach for tissue- and cell-targeted delivery of therapeutic drugs in the lung. However, they can also induce a transient transendothelial migration of leukocytes in the organ as a side effect after endovenous administration of MNPs-DMSA. We demonstrated that monocytes/macrophages constitute the main subpopulation of leukocytes involved in this process. Our recent research found that MNPs-DMSA up-regulated the mRNA expression of E-, L- and P-selectin and macrophage-1 antigen, and increased concentration of tumor necrosis factor-α in lung, in a time dependent manner. The critical relevance of the ß2 integrin-dependent pathway in leukocyte transmigration elicited by MNPs-DMSA was demonstrated by use of knockout mice. Our work characterizes mechanisms of the pro-inflammatory effects of MNPs-DMSA in the lung, and identifies ß2 integrin-targeted interventions as promising strategies to reduce pulmonary side effects of MNPs-DMSA during biomedical applications. In addition, MNPs-DMSA could be used as modulators of lung immune response.


Asunto(s)
Leucocitos/efectos de los fármacos , Pulmón/efectos de los fármacos , Nanopartículas de Magnetita/administración & dosificación , Succímero/administración & dosificación , Migración Transendotelial y Transepitelial/efectos de los fármacos , Animales , Antígenos CD18/metabolismo , Leucocitos/metabolismo , Antígeno de Macrófago-1/efectos de los fármacos , Antígeno de Macrófago-1/metabolismo , Macrófagos/efectos de los fármacos , Ratones , Selectina-P/efectos de los fármacos , Selectina-P/metabolismo , Succímero/química , Factor de Necrosis Tumoral alfa/efectos de los fármacos , Factor de Necrosis Tumoral alfa/metabolismo
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