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1.
Int J Pharm ; 651: 123734, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38142017

RESUMO

The present investigation was focused on the development of Soluplus®-based nanomicelles (NMs) (10 % w/v) loaded with Efavirenz (EFV) (5 mg/mL) and Curcumin (natural bio-enhancer) (CUR) (5, 10 and 15 mg/mL) to improve the oral bioavalability of EFV. Micellar formulations were obtained employing an acetone-diffusion technique. Apparent aqueous solubility was increased up to ∼1250-fold and 25,000-fold for EFV and CUR, respectively. Drug-loaded nanoformulations showed an excellent colloidal stability with unimodal size distribution and PDI values < 0.30. In vitro drug release was 41.5 % (EFV) and 2.6 % (CUR) from EFV-CUR-NMs over 6 h in simulated gastrointestinal fluids. EFV-CUR-loaded NMs resulted as safe nanoformulations according to the in vitro cytocompatibility assays in Caco-2 cells. Furthermore, CUR bio-enhancer activity was demonstrated for those nanoformulations. A CUR concentration of 15 mg/mL produced a significant (p < 0.05) increment (2.64-fold) of relative EFV oral bioavailability. Finally, the active role of the lymphatic system in the absorption process of EFV, after its oral administration was assessed in a comparative pharmacokinetic study in presence and absence of cycloheximide, a lymphatic transport inhibitor. Overall our EFV-CUR-NMs denoted their potential as a novel nanotechnological platform, representing a step towards an optimized "nano-sized" therapy for AIDS patients.


Assuntos
Alcinos , Curcumina , Ciclopropanos , Humanos , Células CACO-2 , Disponibilidade Biológica , Benzoxazinas , Solubilidade , Micelas , Portadores de Fármacos , Administração Oral , Tamanho da Partícula
2.
Int J Mol Sci ; 24(4)2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36834958

RESUMO

Triple negative breast cancer (TNBC) is the most aggressive breast cancer subtype. Currently, paclitaxel (PTX) represents the first-line therapy for TNBC; however it presents a hydrophobic behavior and produces severe adverse effects. The aim of this work is to improve the therapeutic index of PTX through the design and characterization of novel nanomicellar polymeric formulations composed of a biocompatible copolymer Soluplus® (S), surface-decorated with glucose (GS), and co-loaded either with histamine (HA, 5 mg/mL) and/or PTX (4 mg/mL). Their micellar size, evaluated by dynamic light scattering, showed a hydrodynamic diameter between 70 and 90 nm for loaded nanoformulations with a unimodal size distribution. Cytotoxicity and apoptosis assays were performed to assess their efficacy in vitro in human MDA-MB-231 and murine 4T1 TNBC cells rendering optimal antitumor efficacy in both cell lines for the nanoformulations with both drugs. In a model of TNBC developed in BALB/c mice with 4T1 cells, we found that all loaded micellar systems reduced tumor volume and that both HA and HA-PTX-loaded SG micelles reduced tumor weight and neovascularization compared with the empty micelles. We conclude that HA-PTX co-loaded micelles in addition to HA-loaded formulations present promising potential as nano-drug delivery systems for cancer chemotherapy.


Assuntos
Antineoplásicos Fitogênicos , Neoplasias de Mama Triplo Negativas , Camundongos , Humanos , Animais , Paclitaxel , Histamina , Micelas , Antineoplásicos Fitogênicos/química , Linhagem Celular Tumoral , Polietilenoglicóis/química , Polímeros , Portadores de Fármacos/química , Camundongos Endogâmicos BALB C
3.
Pharmaceutics ; 15(1)2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36678805

RESUMO

We have previously demonstrated significant in vitro natriuretic effects of anandamide (AEA) nanoformulation in polymeric nanoparticles, whose size prevents their accumulation in organs, such as the kidneys. Therefore, it is of particular interest to design and test nanostructures that can pharmacologically accumulate in these organs. In this regard, we prepared and characterized polymeric nanomicelles (~14 and 40 nm). Likewise, their biodistribution was determined. Spontaneously hypertensive rats (SHR) and normotensive rats (WKY), n = 3 per group, were divided into five treatment conditions: control, sham, free AEA freshly dispersed in aqueous solution or 24 h after its dispersion, and AEA encapsulated in nanomicelles. The kidneys were the main site of accumulation of the nanoformulation after 24 h. Freshly dispersed free AEA showed its classical triphasic response in SHR, which was absent from all other treatments. Nanoformulated AEA produced a sustained antihypertensive effect over 2 h, accompanied by a significant increase in fractional sodium excretion (FSE %). These effects were not observed in WKY, sham, or free AEA-treated rats after 24 h of its aqueous dispersion. Without precedent, we demonstrate in vivo natriuretic, diuretic, and hypotensive effects of AEA nanoformulation in polymeric nanomicelles, suggesting its possible use as a new antihypertensive agent with intravenous administration and passive renal accumulation.

4.
Pharmaceutics ; 14(5)2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-35631546

RESUMO

Among respiratory infections, tuberculosis was the second deadliest infectious disease in 2020 behind COVID-19. Inhalable nanocarriers offer the possibility of actively targeting anti-tuberculosis drugs to the lungs, especially to alveolar macrophages (cellular reservoirs of the Mycobacterium tuberculosis). Our strategy was based on the development of a mannose-decorated micellar nanoformulation based in Soluplus® to co-encapsulate rifampicin and curcumin. The former is one of the most effective anti-tuberculosis first-line drugs, while curcumin has demonstrated potential anti-mycobacterial properties. Mannose-coated rifampicin (10 mg/mL)-curcumin (5 mg/mL)-loaded polymeric micelles (10% w/v) demonstrated excellent colloidal properties with micellar size ~108 ± 1 nm after freeze-drying, and they remain stable under dilution in simulated interstitial lung fluid. Drug-loaded polymeric micelles were suitable for drug delivery to the deep lung with lung accumulation, according to the in vitro nebulization studies and the in vivo biodistribution assays of radiolabeled (99mTc) polymeric micelles, respectively. Hence, the nanoformulation did not exhibit hemolytic potential. Interestingly, the addition of mannose significantly improved (5.2-fold) the microbicidal efficacy against Mycobacterium tuberculosis H37Rv of the drug-co-loaded systems in comparison with their counterpart mannose-free polymeric micelles. Thus, this novel inhaled nanoformulation has demonstrated its potential for active drug delivery in pulmonary tuberculosis therapy.

5.
PeerJ ; 8: e9045, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32547853

RESUMO

BACKGROUND: Colorectal cancer is the second leading cause of cancer death. Almost half of the patients present recurrence within 5 years after the treatment of the primary tumor, the majority, with metastasis. On the other hand, in the search for new animal models that simulate metastatic cancer, it has been suggested that fibroblasts immersed in the peritumoral stroma (cancer-associated fibroblasts (CAFs)), play a relevant role in the development of cancer. The objective of this study was to identify an adequate animal model to study metastatic colon cancer and the application of new treatments. METHODS: Human CAFs and normal fibroblasts (NF) for transplant and culture were obtained from surgical fresh samples of patients with adenocarcinoma of sigmoid colon. Stromal cell purity was evaluated by morphology and immunostaining with vimentin (VIM) as a fibroblast marker and anti-proColXIα1 as a specific human CAF marker. Phenotypic characterization of cultured stromal cells was performed by co-staining with mesenchymal and epithelial cell markers. For identification in mice, human CAFs were labeled with the PKH26 red fluorescence dye. Cell line HT-29 was used as tumor cells. Transplant in the head of the pancreas of 34 SCID mice was performed in four different groups, as follows: I. 150,000 CAFS (n = 12), IIa. 1.5 million HT29 cells (n = 7), IIb. 150,000 NF+1.5 million HT29 cells (n = 5), III. 150,000 CAFS+1.5 million HT29 cells (n = 10). After euthanasia performed one month later, histological analysis was made using hematoxylin-eosin and anti-proColXIα1. A histopathological score system based on three features (tumor volume, desmoplasia and number of metastasized organs) was established to compare the tumor severity. RESULTS: The CAFs and NF cultured were proColXIα1+/VIM+, proColXIα1/alphaSMA+ and proColXIα1+/CK19+ in different proportions without differences among them, but the CAFs growth curve was significantly larger than that of the NF (p < 0.05). No tumor developed in those animals that only received CAFs. When comparing group II (a + b) vs. group III, both groups showed 100% hepatic metastases. Median hepatic nodules, tumor burden, lung metastases and severity score were bigger in group III vs group II (a + b), although without being significant, except in the case of the median tumor volume, that was significantly higher in group III (154.8 (76.9-563.2) mm3) vs group II (46.7 (3.7-239.6) mm3), p = 0.04. A correlation was observed between the size of the tumor developed in the pancreas and the metastatic tumor burden in the liver and with the severity score. CONCLUSION: Our experiments demonstrate that cultured CAFs have a higher growth than NF and that when human CAFs are associated to human tumor cells, larger tumors with liver and lung metastases are generated than if only colon cancer cells with/without NF are transplanted. This emphasizes the importance of the tumor stroma, and especially the CAFs, in the development of cancer.

6.
Contrast Media Mol Imaging ; 2019: 4087895, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31178670

RESUMO

D-α-Tocopheryl polyethylene glycol 1000 succinate (TPGS) is a Food and Drug Administration (FDA) approved biomaterial that can form nanosized micelles in aqueous solution. TPGS micelles stand as an interesting system to perform drug delivery as they can carry lipophilic drugs and overcome P glycoprotein efflux as well. Therefore, TPGS micelles combined with other copolymers have been reported in many cancer research studies as a carrier for therapeutic drugs. Their ability to reach tumoral tissue can also be exploited to develop imaging agents with diagnostic application. A radiolabeling method with 99mTc for TPGS nanosized micelles and their biodistribution in a healthy animal model as well as their pharmacokinetics and radiolabeling stability in vivo was previously reported. The aim of this work was to evaluate the performance of this radioactive probe as a diagnostic imaging agent compared to routinely available SPECT radiopharmaceutical, 99mTc-sestamibi. A small field of view gamma camera was used for scintigraphy studies using radiolabeled TPGS micelles in two animal models of breast cancer: syngeneic 4T1 murine cell line (injected in BALB/c mice) and chemically NMU-induced (Sprague-Dawley rats). Ex vivo radioactivity accumulation in organs of interest was measured by a solid scintillation counter, and a semiquantitative analysis was performed over acquired images as well. Results showed an absence of tumoral visualization in 4T1 model for both radioactive probes by gamma camera imaging. On the contrary, NMU-induced tumors had a clear tumor visualization by scintigraphy. A higher tumor/background ratio and more homogeneous uptake were found for radiolabeled TPGS micelles compared to 99mTc-sestamibi. In conclusion, 99mTc-radiolabeled TPGS micelles might be a potential SPECT imaging probe for diagnostic purposes.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Micelas , Nanoestruturas , Compostos Radiofarmacêuticos , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Vitamina E , Animais , Avaliação Pré-Clínica de Medicamentos , Estabilidade de Medicamentos , Feminino , Humanos , Neoplasias Mamárias Experimentais/induzido quimicamente , Neoplasias Mamárias Experimentais/diagnóstico por imagem , Metilnitrosoureia , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Compostos Radiofarmacêuticos/farmacocinética , Ratos Sprague-Dawley , Tecnécio Tc 99m Sestamibi/farmacocinética , Distribuição Tecidual , Vitamina E/farmacocinética
7.
Nefrología (Madr.) ; 37(1): 29-33, ene.-feb. 2017. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-160595

RESUMO

Los riñones son órganos vitales que realizan funciones de excreción, equilibrio hidroelectrolítico y producción de hormonas. La nefrona es su unidad estructural y funcional. El número, tamaño y distribución de los componentes de la nefrona contienen información relevante sobre la función renal. La estereología es una rama de la morfometría que permite, aplicando reglas matemáticas, obtener información tridimensional de estructuras biológicas a partir de cortes microscópicos bidimensionales, seriados, paralelos y equidistantes. Ante la complejidad de los estudios estereológicos y la carencia de una bibliografía clara sobre el desarrollo de los mismos, el objetivo de este trabajo es explicar de forma sencilla y con ejemplos, utilizando un modelo animal, los conceptos básicos de estereología, así como el cálculo de los principales parámetros estereológicos renales y que estos puedan ser aplicados en futuros estudios experimentales (AU)


The kidneys are vital organs responsible for excretion, fluid and electrolyte balance and hormone production. The nephrons are the kidney's functional and structural units. The number, size and distribution of the nephron components contain relevant information on renal function. Stereology is a branch of morphometry that applies mathematical principles to obtain three-dimensional information from serial, parallel and equidistant two-dimensional microscopic sections. Because of the complexity of stereological studies and the lack of scientific literature on the subject, the aim of this paper is to clearly explain, through animal models, the basic concepts of stereology and how to calculate the main kidney stereological parameters that can be applied in future experimental studies (AU)


Assuntos
Humanos , Técnicas Estereotáxicas , Néfrons/ultraestrutura , Rim/ultraestrutura , Modelos Animais de Doenças , Técnicas Histológicas/métodos
8.
Eur J Pharm Biopharm ; 113: 211-228, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28087380

RESUMO

During the past few decades, polymeric micelles have raised special attention as novel nano-sized drug delivery systems for optimizing the treatment and diagnosis of numerous diseases. These nanocarriers exhibit several in vitro and in vivo advantages as well as increased stability and solubility to hydrophobic drugs. An interesting approach for optimizing these properties and overcoming some of their disadvantages is the combination of two or more polymers in order to assemble polymeric mixed micelles. This review article gives an overview on the current state of the art of several mixed micellar formulations as nanocarriers for drugs and imaging probes, evaluating their ongoing status (preclinical or clinical stage), with special emphasis on type of copolymers, physicochemical properties, in vivo progress achieved so far and toxicity profiles. Besides, the present article presents relevant research outcomes about polymeric mixed micelles as better drug delivery systems, when compared to polymeric pristine micelles. The reported data clearly illustrates the promise of these nanovehicles reaching clinical stages in the near future.


Assuntos
Micelas , Nanomedicina , Polímeros/química , Portadores de Fármacos
9.
Nefrologia ; 37(1): 29-33, 2017.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-27462017

RESUMO

The kidneys are vital organs responsible for excretion, fluid and electrolyte balance and hormone production. The nephrons are the kidney's functional and structural units. The number, size and distribution of the nephron components contain relevant information on renal function. Stereology is a branch of morphometry that applies mathematical principles to obtain three-dimensional information from serial, parallel and equidistant two-dimensional microscopic sections. Because of the complexity of stereological studies and the lack of scientific literature on the subject, the aim of this paper is to clearly explain, through animal models, the basic concepts of stereology and how to calculate the main kidney stereological parameters that can be applied in future experimental studies.


Assuntos
Nefropatias/patologia , Néfrons/ultraestrutura , Algoritmos , Animais , Glomérulos Renais/ultraestrutura , Camundongos , Microscopia/métodos , Modelos Animais , Fotomicrografia
10.
Anticancer Agents Med Chem ; 17(3): 359-364, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-26552391

RESUMO

BACKGROUND: Chemotherapy is one of the most common approaches for cancer treatment. Particularly Doxorubicin has been proven to be effective in the treatment of many soft and solid tumors for locally advanced and metastatic cancer. It is not easy to clinically evaluate the chemotoxic or chemoprotective effect of some drugs, even more when there is a subclinical toxicity. OBJECTIVE: To determine the usefulness of the hepatobiliary, colloid and cardiac scintigraphies, employing99mTcdisida, 99mTc-phytate and 99mTc-sestamibi respectively, in the evaluation of the hepato and cardiotoxicity of two chemotherapeutic treatments assessed in rats. METHOD: Two groups were submitted to doxorubicin (DOX) treatment and one was co-administered with histamine (DOX+HIS). Static 99mTc-phytate and 99mTc-sestamibi scintigraphies as well as a dynamic 99mTc-disida study were performed in a small field of view gamma camera at: 0 weeks (control), 1 week and 2 weeks of treatment. Imagenological parameters were calculated: Liver/Bone Marrow ratio (L/BM), Heart/Background ratio (H/B) and time to the maximum (Tmax) for 99mTc-phytate, 99mTc-sestamibi and 99mTc-disida extraction, respectively. RESULTS: Control (L/BM= 98±3; H/B=2.3±0.4; Tmax=8±3), DOX (L/BM: 85±3, 80±3; H/B, 3.5±0.5, 3.3±0.5 and Tmax 6±1, 4±1) for 1 and 2 weeks respectively and DOX+HIS (L/BM: 99±0.3, 98±1; H/B 2.9±0.5, 2.9±0.5 and Tmax, 8±2, 9±2) for 1 and 2 weeks, respectively. Histological analysis showed cardio and hepatotoxicity induced by doxorubicin. CONCLUSION: Imagenological parameters showed differences among treated and control groups and between both chemotherapy treatments. Thus, these radiopharmaceutical functional approaches were able to reflect heart and liver toxicity produced by doxorubicin.


Assuntos
Antineoplásicos/efeitos adversos , Doxorrubicina/efeitos adversos , Coração/efeitos dos fármacos , Histamina/efeitos adversos , Fígado/efeitos dos fármacos , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Cardiotoxicidade , Relação Dose-Resposta a Droga , Doxorrubicina/administração & dosagem , Doxorrubicina/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Histamina/administração & dosagem , Histamina/farmacologia , Masculino , Estrutura Molecular , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade
11.
Nucl Med Biol ; 44: 62-68, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27821346

RESUMO

INTRODUCTION: In recent years, nanomedicines have raised as a powerful tool to improve prevention, diagnosis and treatment of different pathologies. Among the most well investigated biomaterials, D-α-tocopheryl polyethylene glycol succinate (also known as TPGS) has been on the spot for the last decade. We therefore designed a method to biologically characterize TPGS-based nanomicelles by labeling them with 99mTc. METHODS: Labeling process was performed by a direct method. The average hydrodynamic diameter of TPGS nanomicelles was measured by dynamic light scattering and radiochemical purity was assessed by thin layer chromatography. Imaging: a dynamic study was performed during the first hour post radioactive micelles administration in a gamma camera (TcO4- was also administered for comparative purposes). Then two static images were acquired in ventral position: 1h and 12h post injection. Blood pharmacokinetics of 99mTc-TPGS during 24h was performed. RESULTS: Images revealed whole body biodistribution at an early and delayed time and semiquantification was performed in organs of interest (%Total counts: soft tissue 6.1±0.5; 3.9±0.1, Bone 1.2±0.2; 1±0.1, Heart 1.5±0.6; 0.7±0.3, Kidneys 16.6±1.3; 26.5±1.7, Liver 8.6±1.1; 11.1±0.1 for 1 and 12 h post injection respectively). CONCLUSION: This work demonstrated that TPGS based nanomicelles are susceptible to be radiolabeled with 99mTc thus they can be used to perform imaging studies in animal models. Moreover radiolabeling of these delivery nano systems reveals their possibility to be used as diagnostic agents in the near future.


Assuntos
Micelas , Imagem Molecular/métodos , Nanotecnologia , Vitamina E/química , Animais , Marcação por Isótopo , Ratos , Ratos Sprague-Dawley , Tecnécio/química , Distribuição Tecidual , Vitamina E/farmacocinética
12.
Rev. mex. trastor. aliment ; 6(2): 129-136, jul.-dic. 2015.
Artigo em Espanhol | LILACS-Express | LILACS | ID: lil-791596

RESUMO

Este trabajo describe el papel que juega la imagen corporal en la psicopatología de los trastornos alimentarios, desde la manifestación de grados leves de insatisfacción hasta las distorsiones que pueden llegar a niveles de alta severidad y su incidencia como factor de riesgo, en la generación del trastorno y como predictor de recaídas. Se destaca la relevancia de la construcción social de la imagen corporal y de la necesidad de la consideración de los factores contextuales para su comprensión y para el diseño de las intervenciones específicas en el tratamiento. Se enfatiza la importancia de las alteraciones en la imagen corporal como núcleo duro de la psicopatología, como factor de mantenimiento y como indicador pronóstico. Detalla inicialmente los componentes perceptuales, cognitivos y de comportamiento del constructo y su estudio en diferentes poblaciones. Se mencionan a continuación algunos instrumentos que ayudan a precisar las dimensiones de este complejo concepto. Finalmente describe las diferentes modalidades de intervención, principalmente el abordaje psicoterapéutico (individual, vincular y grupal), la utilización de realidad virtual y la aplicación de intervenciones basadas en mindfulness , ubicando esta intervención específica dentro del tratamiento general, en una segunda fase, después del control de la sintomatología.


This paper explore the role that body image plays in the psychopathology of eating disorders, from dissatisfaction in one extreme of the continuum through distortion at the other end, its incidence as a risk factor in the generation of the disorder and as a relapse predictor. Highlights the relevance of the social construction of body image and hence, the need for consideration of contextual factors for its understanding and for the design of specific treatment interventions. Emphasizes the importance of body image disturbances as a hard core of psychopathology, as a maintenance factor, and indicator for prognosis. It initially details body image' perceptual, cognitive and behavioral components and research in different contexts and populations. Some instruments that help to define the dimentions of this complex concept are listed. Finally, describes different types of intervention, mainly psychotherapy approaches (individual, family and couple and group psychotherapy), the use of virtual reality and mindfulness based interventions, placing these specific interventions within the overall treatment, in a second phase, after the control of symptomatology.

13.
J Nucl Med Technol ; 42(4): 292-5, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25342185

RESUMO

UNLABELLED: In accord with as-low-as-reasonably-achievable and good-manufacturing-practice concepts, the present study evaluated the efficiency of radioactivity decontamination of materials commonly used in laboratory surfaces and whether solvent spills on these materials affect the findings. METHODS: Four materials were evaluated: stainless steel, a surface comprising one-third acrylic resin and two-thirds natural minerals, an epoxy cover, and vinyl-based multipurpose flooring. Radioactive material was eluted from a (99)Mo/(99m)Tc generator, and samples of the surfaces were control-contaminated with 37 MBq (100 µL) of this eluate. The same procedure was repeated with samples of surfaces previously treated with 4 solvents: methanol, methyl ethyl ketone, acetone, and ethanol. The wet radioactive contamination was allowed to dry and then was removed with cotton swabs soaked in soapy water. The effectiveness of decontamination was defined as the percentage of activity removed per cotton swab, and the efficacy of decontamination was defined as the total percentage of activity removed, which was obtained by summing the percentages of activity in all the swabs required to complete the decontamination. RESULTS: Decontamination using our protocol was most effective and most efficacious for stainless steel and multipurpose flooring. Moreover, treatment with common organic solvents seemed not to affect the decontamination of these surfaces. Decontamination of the other two materials was less efficient and was interfered with by the organic solvents; there was also great variability in the overall results obtained for these other two materials. CONCLUSION: In expanding our laboratory, it is possible for us to select those surface materials on which our decontamination protocol works best.


Assuntos
Descontaminação/métodos , Laboratórios , Radioisótopos/isolamento & purificação , Composição de Medicamentos , Controle de Qualidade , Radioatividade , Radioisótopos/química , Propriedades de Superfície
14.
Biol Trace Elem Res ; 151(3): 441-5, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23271679

RESUMO

Iron fortification of foods continues to be one of the preferred ways of improving the iron status of the population. Dairy product is a common product in the diet; therefore, it is a plausible vehicle for iron fortification. This study aims to investigate the bioavailability of ferrous gluconate stabilised with glycine (FGSG) in a fresh cheese fortified with zinc. The iron bioavailability of fresh cheese fortified with either FGSG and with or without zinc and FGSG in aqueous solution and a water solution of ferrous ascorbate (reference dose) was studied using double radio iron ((55)Fe and (59)Fe) erythrocyte incorporation in 15 male subjects. All subjects presented with normal values for iron status parameters. The geometric mean of iron bioavailability for the water solution of FGSG was 38.2 %, adjusted to 40 % from reference doses (N.S.). Iron bioavailability in fresh cheese fortified with Ca and Zn was 15.4 % and was 23.1 % without Zn, adjusted to 40 % from reference doses (N.S.). The results of the present study show that the novel iron compound ferrous gluconate stabilised with glycine in a fresh cheese matrix is a good source of iron and can be used in iron fortification programmes.


Assuntos
Queijo/análise , Compostos Ferrosos/metabolismo , Alimentos Fortificados/análise , Glicina/metabolismo , Disponibilidade Biológica , Cálcio/análise , Cálcio/metabolismo , Compostos Ferrosos/química , Glicina/química , Humanos , Masculino , Zinco/análise , Zinco/metabolismo
15.
J Nucl Med Technol ; 40(4): 271-4, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23024339

RESUMO

UNLABELLED: The aim of the present work was to validate a paper chromatography system as an alternative way to determine the radiochemical purity of Na(18)F. METHODS: The evaluated parameters were specificity, limit of quantification, measurement interval, linearity, precision, accuracy, and robustness. RESULTS: The proposed method proved to be linear (P > 0.05; r(2) = 1.000), precise (relative SD, 8.6%), accurate (mean recovery, 95.9%; relative SD, 1.5%-1.8%), and robust under different conditions since no influence of the operative variables on the chromatographic performance was observed. CONCLUSION: This system can be used as a reliable alternative method to determine the radiochemical purity of Na(18)F samples that can be easily performed in PET radiopharmacies at low cost.


Assuntos
Cromatografia em Papel/métodos , Radioisótopos de Flúor , Radioquímica/métodos , Fluoreto de Sódio/análise , Fluoreto de Sódio/química , Fenômenos Químicos , Controle de Qualidade
16.
Rev. Soc. Cardiol. Estado de Säo Paulo ; 22(2,supl.A): 15-18, abr.-jun. 2012. graf
Artigo em Português | LILACS | ID: lil-679839

RESUMO

As mudanças biológicas, psicológicas, cognitivas e sociais que ocorrem com intensidade na adolescência interferem de forma dinâmica no comportamento do adolescentes. As escolhas alimentares não dependem somente da disponibilidade e das preferências, mas também dos fatores cognitivos, tais como o conhecimento sobre os benefícios e o custo associados aos alimentos. este estudo tem como objetivo avaliar o nível de conhecimento em nutrição entre alunos do ensino Fundamental II de uma Escola Privada da zona sul de São Paulo. Estudo transversal do tipo descritivo desenvolvido com com alunos do Ensino Fundamental II. Para avaliar o nível de conhecimento dos alunos, utilizou-se o questionário de "Conhecimentos Gerais em Nutrição - Escala de Conhecimento Nutricional". O instrumento enfoca três partes: a primeira contém quatro questões sobre a relação entre dieta e doenças: a segunda parte tem sete questões sobre o conteúdo de fibras e lipídeos nos alimentos e a terceira consiste em uma questão sobre a quantidade de porções de frutas e hortaliças que uma pessoa deve consumir, sendo distribuído um ponto para cada resposta correta. Em relação ao nível de conhecimento nutricional. obeservou-se que 22,22% dos alunos apresentam baixo nível de conhecimento sobre nutrição, 65,43% moderado e 12,34% alto. Com base no presente estudo, conclui-se que os alunos do Ensino Fundamental II apresentam bom nível de conhecimento em nutrição.


The biological, psychological, cognitive and social changes that occur with intensity in adolescence affect dynamically eating behavior in teenagers. Feeding choices do not depend on the availability and preferences, but also of cognitive factors such as knowledge about the benefits and costs associated with the food. The target of this study is to evaluate then level of nutrional knowledge among students of a private Primary School in the south zone of São Paulo. The study was of transversal descriptive type developed with students of a Primary School II in the south zone of São Paulo. "General Knowledge in Nutrition - Nutrition Knowledge Scale" questionnaire were used to evaluate the knowledge level of the students. The intrument focuses three parts: the first one contains four questions about the relation among diet and food; the second part has seven questions about the contents of fibers and lipids in food and the last one consists of question about quantity servings of fruits and vegetables that a person has been consuming, being distributed one point for each correct answer. In regard to the knowledge it was observed 22,22% of the students have lack of knowledge in nutrition, 64,43% moderate knowledge and 12,34% high. based on presente study it was concluded that students of Primary School II show a good knowledge level about nutrition.


Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Adolescente , Comportamento Alimentar , Nutrição do Adolescente/educação , Estudos Transversais , Epidemiologia Descritiva , Sobrepeso
17.
Rev. med. nucl. Alasbimn j ; 14(54)oct. 2011. ilus, tab, graf
Artigo em Espanhol | LILACS | ID: lil-609895

RESUMO

El objetivo consistió en evaluar la utilidad del 99mTc-MIBI como marcador para diagnóstico y seguimiento de la progresión tumoral del NMSC en un modelo de carcinogénesis completa en ratones. Los animales en estudio fueron inyectados con 99mTc-MIBI a diferentes tiempos y eutanasiados. Se disecaron muestras de tumor y piel sana para evaluar la captación del radiofármaco y realizar el diagnóstico histológico. En animales con 22 semanas de progresión tumoral se observó una diferencia significativa en la captación del 99mTc-MIBI entre piel sana y NMSC. El protocolo que mejor se adapta al uso del 99mTc-MIBI como marcador para el diagnóstico y seguimiento de la progresión tumoral en ratones portadores de NMSC inducidos es la administración i.v de 1 mCi de 99mTc-MIBI con adquisición de datos a los 30 minutos post inyección. Se observó que a medida que los tumores progresan, la captación de 99mTc-MIBI disminuye respecto a la piel normal.


The aim of the work was to evaluate the usefulness of 99mTc-MIBI as a tracer for the tumor diagnosis and progression of NMSC in a chemically induced model in mice. After administration of 99mTc-MIBI animals were sacrificed at different times. Samples of tumor and healthy skin were dissected in order to perform histological analysis and to evaluate 99mTc-MIBI uptake. Animals under 22 weeks of tumor evolution showed a statistically difference in 99mTc-MIBI uptake between healthy skin and NMSC. Our results showed that the better protocol for the study of the tumor diagnosis and progression of NMSC in mice is the administration of 1 mCi of 99mTc-MIBI and acquisition of images 30 minutes post injection. Results showed that, as tumor progresses, the uptake of 99mTc-MIBI is significantly lower than healthy skin.


Assuntos
Animais , Camundongos , Neoplasias Cutâneas , Compostos Radiofarmacêuticos , Distribuição Tecidual , Fatores de Tempo , Modelos Animais de Doenças , Compostos Radiofarmacêuticos/farmacocinética , /farmacocinética
18.
Nucl Med Commun ; 30(9): 706-12, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19536038

RESUMO

OBJECTIVE: To evaluate the therapeutic effects of a (32)P-patch in the treatment of a murine melanoma. MATERIALS AND METHODS: Thirty male C57BL6 mice were divided into two groups: treated and control. Superficial tumors were induced in both groups by injecting B16F1 melanoma at about 10 cells/mouse subcutaneously. Tumors developed 10-15 days after transplantation and the (32)P-patch was applied on palpable tumors of the treated group. Tumor growth was followed up in both groups by measuring tumor size with a caliper. After the follow-up period, the animals were killed and tumor samples of the treated and control groups were collected for histological study by preparing paraffin sections stained with hematoxylin-eosin. RESULTS: The (32)P-patch showed the absence of radioactivity leakage in vitro and the homogeneous distribution of the radionuclide. The skin surface at the application site of the (32)P-patch appeared hairless, and erythema developed, but reversed to normal after a few days in the treated group. Control of tumor growth was achieved in the treated group compared with the control group, although complete remission did not occur. CONCLUSION: The (32)P-patch tested for the treatment of a murine melanoma model showed its efficacy, as tumor growth was retarded after application of the patch Nevertheless, adjustment of some therapeutic parameters and/or combining the patch with other treatment modalities may be necessary to achieve complete regression. The P-patch represents a powerful tool to individualize the treatment of melanoma.


Assuntos
Melanoma/radioterapia , Radioisótopos de Fósforo/administração & dosagem , Radioisótopos de Fósforo/uso terapêutico , Neoplasias Cutâneas/radioterapia , Administração Tópica , Animais , Braquiterapia , Linhagem Celular Tumoral , Fracionamento da Dose de Radiação , Masculino , Melanoma/patologia , Camundongos , Traçadores Radioativos , Neoplasias Cutâneas/patologia , Carga Tumoral
19.
Nucl Med Biol ; 35(2): 233-7, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18312834

RESUMO

OBJECTIVE: The objective of this study was to design and evaluate a 32P patch for the treatment of skin diseases. MATERIALS AND METHODS: The patch was prepared from chromic phosphate 32P and silicone. Bioelimination and biodistribution in healthy and treated animals, and the therapeutic efficacy of two treatment schemes (single dose and fractionated dose) in an animal model of skin cancer were studied. RESULTS: Based on the bioelimination and biodistribution studies, no leakage of 32P from the patch was observed. The treated tumors reduced their mean diameter compared to controls. The single-dose therapeutic scheme showed a higher number of complete and partial remissions compared to the fractionated scheme. These results were confirmed by histopathological analysis of the samples. CONCLUSION: The 32P patch was designed and produced according to specifications for the treatment of superficial lesions of the skin. Although the 32P patch is an open source, it behaves like a sealed one for use in brachytherapy treatments.


Assuntos
Braquiterapia/instrumentação , Radioisótopos de Fósforo/farmacocinética , Neoplasias Cutâneas/radioterapia , Administração Cutânea , Animais , Braquiterapia/métodos , Modelos Animais de Doenças , Fracionamento da Dose de Radiação , Relação Dose-Resposta à Radiação , Feminino , Taxa de Depuração Metabólica , Camundongos , Radioisótopos de Fósforo/uso terapêutico , Distribuição Tecidual , Resultado do Tratamento
20.
Rev. med. nucl. Alasbimn j ; 10(39)Jan. 2008.
Artigo em Espanhol | LILACS | ID: lil-480514

RESUMO

Objetivo: Evaluar la biodistribución de 99mTc-GR en un modelo animal de anemia ferropénica. Materiales y métodos: Se utilizaron ratas alimentadas con dietas con diferente contenido de Fe: grupo A (anemia severa, 6.5 ppm), grupo B (anemia moderada, 18 ppm) y grupo C (control, 100 ppm). Se realizó la marcación in vivo de los 99mTc-GR y se evaluó la EBM y su biodistribución a los 30 minutos y a las 24 horas en sangre, hígado, bazo, tracto gastrointestinal, riñones, corazón y pulmones. Los resultados se expresaron como concentración de actividad porcentual (CA por ciento). Resultados: En todos los grupos la EBM fue superior al 98 por ciento. Se observó un aumento de CA por ciento en bazo a las 24 horas en el grupo A, acompañado de una disminución de la CA por ciento del pool sanguíneo posiblemente por aumento del secuestro esplénico de los GR. En los tres grupos hubo un aumento de la CA por ciento en riñón a las 24 horas. Conclusión: La biodistribución de 99mTc-GR se ve modificada en la anemia ferropénica.


Aim: To evaluate the biodistribution of 99mTc-RBC in an animal model of ferropenic anemia. Materials and methods: We used rats which were fed with different iron contents diets: group A (severeanemia, 6.5 ppm), group B (moderate anemia, 18 ppm) and group C (control, 100 ppm). We performed the in vivo labeling of RBC and evaluated the labeling efficiency and the biodistribution at 30 minutes and 24 hours in blood, liver, spleen, gastrointestinal tract, kidneys, heart and lungs. The results were expressed as activity concentration percentage (CA percent). Results: In all groups the labeling efficiency was higher than 98 percent. We observed an increase of CA percent in spleen at 24 hours in the group A, followed by a decrease of CA percent in blood. This could be a consequence of an increase of splenic uptake of RBC. An increase in CA percent in kidney was obtained at 24 hours for all the groups. Conclusion: An alteration in the RBC biodistribution is observed in an animal model of ferropenic anemia.


Assuntos
Animais , Feminino , Ratos , Anemia Ferropriva , Anemia Ferropriva/metabolismo , Compostos de Tecnécio , Eritrócitos/metabolismo , Tecnécio , Compostos de Tecnécio/farmacocinética , Distribuição Tecidual , Fatores de Tempo , Modelos Animais de Doenças , Ratos Sprague-Dawley , Tecnécio/farmacocinética
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