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1.
Eur J Prosthodont Restor Dent ; 32(3): 326-334, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39038187

RESUMEN

OBJECTIVES: This in vitro study focused on verifying the influence of different ambient light conditions on the accuracy and precision of models obtained from digital scans. METHODOLOGY: To measure the tested illuminances: chair light/reflector; room light, and natural light at the time of scanning, a luxmeter was used. From the STL file, nine experimental groups were formed. RESULTS: Of the nine specific combinations between the three IOS and the three types of lighting, it was verified that for all of them, as well as the ICC, the accuracy was also excellent, in which the measured values were not significantly influenced by the IOS brand (p = 0.994) nor by the type of lighting (p = 0.996). For precision data, GLM indicated a statistically significant interaction between IOS and lighting type. Under LS, accuracy was significantly higher with 3Shape® than with CS 3600 CareStream®, which had significantly higher accuracy than Virtuo Vivo™ Straumann®. CONCLUSIONS: The models obtained with the three IOS evaluated exhibited excellent accuracy under the different illuminance tested and the 3Shape® under the three illuminance conditions was the device that presented the best precision, specifically when using LC and LS.


Asunto(s)
Iluminación , Humanos , Técnicas In Vitro , Modelos Dentales , Luz , Reproducibilidad de los Resultados
2.
Appl Radiat Isot ; 170: 109559, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33476941

RESUMEN

From a commercial supplier, three independent lots of an aqueous solution containing 223Ra in equilibrium with its deteriorating progeny were considered for standardization, by using live-time anticoincidence counting (LTAC) in the Laboratório Nacional de Metrologia das Radiações Ionizantes (LNMRI) Brazil. The ionization chamber calibration factors were obtained using measurements of independent lots of 223Ra in LTAC considering the absolute method in order to evaluate the constancy and reproducibility of the standardization. The calibration factors of three high-performance well-type ionization chamber systems and four commercial well-type ionization chambers were determined. The LTAC results showed that lots 2 and 3 were 1069.88 and 1097.44 kBq/kg, with corresponding relative standard uncertainties 0.12% and 0.20%, respectively. The spectrometry method results of each lot value were classified as positive by ANOVA hypothesis testing. The emission probabilities relating to the X- and γ-rays in region from 81 to 830 keV ware determined. Hence, LNMRI can provide calibration services for 223Ra.

3.
Appl Radiat Isot ; 166: 109323, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32795698

RESUMEN

There are few long-lived radionuclides yielding high intensity gamma-rays emission with energies ranging from 100 keV to 500 keV that can be applied as radioactive gamma standard to calibrate HPGe detectors. Furthermore, this energy range represents the main emitted energies of the majority of radionuclides used in nuclear medicine. The Brazilian National Laboratory for Ionizing Radiation Metrology (LNMRI/IRD/CNEN) has attempted to identify radionuclides that have the potential to be used as a calibration source due to their long half-life as well as their emission spectrum. Hence, LNMRI promotes standardization studies of gamma-emitting radionuclides that meet these criteria on order to disseminate them. Thorium-229, with its well-defined energies and relatively high intensities, is one such candidate radionuclide for the energy and full-energy peak efficiency calibration of high-purity gamma spectrometers. Thorium-229 was standardized by the method of 4παß(LS)-γ(NaI(Tl)) live timed anticoincidence counting. The emission intensities of gamma-rays associated with the decay of 229Th have been determined by HPGe gamma ray spectrometry with accuracy and precision. The results are in agreement with current literature data.

4.
J Fish Dis ; 41(7): 1041-1048, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29770449

RESUMEN

Monogeneans are ectoparasites that may cause losses in production and productivity in the aquaculture of Colossoma macropomum. Chemotherapeutics used in aquaculture usually have major adverse effects on fish; hence, the use of essential oils has been considered advantageous, but these are not soluble in water. Thus, the use of nanostructures to enhance water solubility of compounds and improve bioactivity may be very promising. This study investigated the antiparasitic activity of nanoemulsion prepared with Copaifera officinalis oleoresin (50, 100, 150, 200 and 300 mg/L), against monogenean parasites from the gills of C. macropomum. The particle size distribution and zeta potential suggested that a potentially kinetic stable system was generated. The nanoemulsion from C. officinalis oleoresin achieved high efficacy (100%) at low concentrations (200 and 300 mg/L) after 15 min of exposure. This was the first time that a nanoemulsion was generated from C. officinalis oleoresin using a solvent-free, non-heating and low-energy method. Moreover, this was the first time that an antiparasitic against monogeneans on fish gills, based on nanoemulsion of C. officinalis oleoresin, was tested.


Asunto(s)
Antiparasitarios/farmacología , Characiformes , Fabaceae/química , Extractos Vegetales/farmacología , Trematodos/efectos de los fármacos , Infecciones por Trematodos/veterinaria , Animales , Relación Dosis-Respuesta a Droga , Emulsiones , Enfermedades de los Peces/tratamiento farmacológico , Enfermedades de los Peces/parasitología , Nanoestructuras/análisis , Infecciones por Trematodos/tratamiento farmacológico , Infecciones por Trematodos/parasitología
5.
J Fish Dis ; 41(3): 443-449, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29194663

RESUMEN

Outbreaks of diseases pose a major threat to sustainable aquaculture development worldwide. Application of herbal products to combat parasitic diseases provides an alternative approach for sustainable aquaculture. This study investigated the in vitro antiparasitic effects of an oil-in-water nanoemulsion prepared using the essential oil from Pterodon emarginatus, against monogeneans infesting Colossoma macropomum. Gill arches from C. macropomum (47.6 ± 14.5 g and 13.5 ± 1.4 cm) that were naturally parasitized by Anacanthorus spathulatus, Notozothecium janauachensis and Mymarothecium boegeri were immersed in different dispersions of the P. emarginatus nanoemulsions (0, 50, 100, 200, 400 and 600 mg/L). The major compounds presented in the essential oil of P. emarginatus were ß-elemene, ß-caryophyllene and α-humulene. Characterization of these nanoemulsions showed that they have a small mean droplet size and low polydispersity index, which is concordant with stable systems. In this in vitro trial, the P. emarginatus nanoemulsion concentrations of 100, 200, 400 and 600 mg/L presented 100% helminthic efficacy against monogeneans of the gills of C. macropomum. The highest two concentrations used (400 and 600 mg/L) were seen to immobilize the parasites after only 15 min. Therefore, it would be worthwhile testing these concentrations in therapeutic baths against monogeneans of C. macropomum.


Asunto(s)
Antihelmínticos/farmacología , Characiformes , Fabaceae/química , Enfermedades de los Peces/prevención & control , Aceites Volátiles/farmacología , Trematodos/efectos de los fármacos , Infecciones por Trematodos/veterinaria , Animales , Emulsiones , Enfermedades de los Peces/parasitología , Nanoestructuras/análisis , Infecciones por Trematodos/parasitología , Infecciones por Trematodos/prevención & control
6.
Appl Radiat Isot ; 134: 64-67, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28942991

RESUMEN

Traceability in Nuclear Medicine Service (NMS) measurements was checked by the Institute of Radioprotection and Dosimetry (IRD) through the Institute of Energy and Nuclear Research (IPEN). In 2016, IRD ran an intercomparison program and invited Brazilian NMS authorized to administer 131I to patients. Sources of 131I were distributed to 33 NMSs. Three other sources from the same solution were sent to IRD, after measurement at IPEN. These sources were calibrated in the IRD reference system. A correction factor of 1.013 was obtained. Ninety percent of the NMS comparisons results are within ±10% of the National Laboratory of Metrology of Ionizing Radiation (LNMRI) value, the Brazilian legal requirement.


Asunto(s)
Instituciones de Atención Ambulatoria , Radioisótopos de Yodo/análisis , Servicio de Medicina Nuclear en Hospital , Radiofármacos/análisis , Brasil , Calibración , Competencia Profesional , Control de Calidad , Reproducibilidad de los Resultados , Factores de Tiempo , Incertidumbre
7.
Appl Radiat Isot ; 109: 389-392, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26805708

RESUMEN

(123)I is widely used for radiodiagnostic procedures. It is produced by reaction of (124)Xe (p,2n) (123)Cs →(123)Xe →(123)I in cyclotrons. (121)Te and (125)I appear in a photon energy spectrum as impurities. An activity of (121)Te was calibrated absolutely by sum-peak method and its photon emitting probability was estimated, whose results were consistent with published results.

8.
Appl Radiat Isot ; 109: 236-241, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26688362

RESUMEN

Since the inception of its proficiency test program to evaluate radionuclide measurement in hospitals and clinics, the National Metrology Laboratory of Ionizing Radiation-LNMRI, that represents Brazilian National Metrology Institute (NMI) for ionizing radiation has expanded its measurement and calibration capability. Requirements from the National Health Surveillance Agency from Ministry of Health (ANVISA), to producers of radiopharmaceuticals provided an opportunity to improve the full traceability chain to the highest level. Fluorodeoxyglucose (FDG-(18)F) is the only radiopharmaceutical simultaneously produced by all Brazilian radiopharmaceutical production centers (RPCs). By running this proficiency test, LNMRI began to provide them with the required traceability. For evaluation, the ratio of RPC to reference value results and ISO/IEC17043:2010 criteria were used. The reference value established as calibration factor on the secondary standard ionization chamber was obtained from three absolute measurements systems, and routinely confirmed in each round of proficiency test by CIEMAT/NIST liquid scintillation counting. The γ-emitting impurities were checked using a High-Purity Germanium (HPGe) detector. The results show that Brazilian RPCs are in accordance with (accuracy within ±10%) the Brazilian standard for evaluation of measurements with radionuclide calibrators (CNEN NN 3.05., 2013). Nevertheless, the RPCs should improve the methodology of uncertainty estimates, essential when using the statistical criteria of ISO/IEC 17043 standard, in addition to improving accuracy to levels consistent with their position in the national traceability chain.


Asunto(s)
Radioisótopos de Flúor/análisis , Radioisótopos de Flúor/normas , Sector Público/normas , Radiometría/métodos , Radiometría/normas , Brasil , Estándares de Referencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
9.
Community Dent Health ; 32(2): 77-82, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26263599

RESUMEN

UNLABELLED: Pregnancy is a period in which several physical and emotional changes occur. These changes in pregnant women's mouths promote changes that need to be known by dentists, so that they can provide the necessary care to women. PURPOSE: To gather data from published studies on the knowledge of dentists about the oral health of pregnant women. METHODS: Papers published between 2003 and 2013 containing surveys on the topic under study were searched. Fourteen studies were selected and grouped into work areas. RESULTS: Dentists have doubts and fears about the care of pregnant women, to a greater or lesser degree, especially with regard to the use of X-rays, prescriptions and ideal gestational period of treatment. CONCLUSION: The results suggest a need to improve dentists' knowledge regarding dental care of pregnant women especially as during pregnancy women may acquire new habits relevant to the oral health of their children.


Asunto(s)
Odontólogos , Educación en Odontología , Salud Bucal , Mujeres Embarazadas , Actitud del Personal de Salud , Atención Odontológica , Odontólogos/psicología , Femenino , Humanos , Pautas de la Práctica en Odontología , Embarazo , Atención Prenatal
10.
Climacteric ; 18(2): 311-5, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25263313

RESUMEN

OBJECTIVE: To investigate the possible association between periodontal changes and osteoporosis in postmenopausal women through a longitudinal study. METHODS: This longitudinal study included 33 patients. The participants were divided into three groups according to the bone mineral density assessed in the lumbar region: normal bone (G1, n = 15), osteopenia (G2, n = 12) and osteoporosis (G3, n = 6). Periodontal evaluation included clinical attachment level, probing depth, gingival bleeding index and visible plaque index, evaluated by two examiners blinded to systemic bone condition. The statistical process included the t-test for paired samples, with a significance level of 5% to check for changes in periodontal parameters considered at initial and final systemic bone density. RESULTS: The results showed that, after follow-up, there was a significant increase in gingival bleeding index in the group of women who had normal initial bone condition and progressed to osteopenia (after 3 years, 59.89%, p = 0.010) and osteoporosis (after 3 years, 74.37%, p = 0.035). In addition, the group diagnosed with osteopenia at baseline who progressed to osteoporosis after 3 years also showed a significant increase in gingival bleeding index (p < 0.001). CONCLUSIONS: The findings suggest that periodontal changes can be associated with osteoporosis in postmenopausal women.


Asunto(s)
Osteoporosis Posmenopáusica/complicaciones , Enfermedades Periodontales/complicaciones , Posmenopausia/fisiología , Anciano , Densidad Ósea , Índice de Placa Dental , Femenino , Estudios de Seguimiento , Humanos , Estudios Longitudinales , Persona de Mediana Edad , Índice Periodontal
11.
Rev. ciênc. farm. básica apl ; Rev. ciênc. farm. básica apl;35(1)mar. 2014.
Artículo en Portugués | LILACS | ID: lil-718818

RESUMEN

Entre as formas farmacêuticas sólidas de uso oral mais preparadas nas farmácias magistrais está a cápsula gelatinosa dura. O processo de manipulação de cápsulas apresenta alguns pontos críticos como a mistura e o fluxo dos pós, que podem interferir na obtenção de cápsulas na dose certa. Assim o objetivo foi analisar e validar o procedimento de manipulação de cápsulas por encapsulamento manual por nivelamento, considerando as características de fluxo e dose das formulações magistrais. A seleção dos produtos farmacêuticos (6) foi baseada na dose, fluxo e metodologia analítica validada por UV. A validação do processo consistiu na análise do peso médio, uniformidade de dose e teor de cinco lotes de cada produto preparados por dois manipuladores. Foi elaborado um procedimento escrito pelo método de nivelamento manual para os produtos metformina 500mg (MTF); paracetamol 250 mg (PCT); cetoconazol 200mg (CTZ); nimesulida 150 mg (NIM); riboflavina 20 mg(RIB) e glibenclamida 5 mg (GLB). O procedimento de manipulação foi validado para os produtos MTF, PCT,CTZ, NIM e RIB, exceto para o produto GLB, devido a reprovação de quatro lotes no teste de uniformidade de conteúdo. Os resultados nos levam a concluir que fármacos de dose acima de 20 mg (fluxo bom ou ruim) são menos susceptíveis à reprovação. O mesmo não acontece para fármacos de doses ≤ 5 mg, demonstrando que quanto menor a dose, maior a dificuldade de obter um produto na dose correta. Também foi possível verificar que o manipulador interfere na obtenção do produto de qualidade...


Among the solid dosage forms for oral use prepared regularly in compounding pharmacies is the hard gelatin capsule. The process of com pounding capsuleshas some critical features, such as the mixing and flow of powders, which can interfere with the production of capsules containing the right dose. Thus, the aim here was to analyze and validate the procedure for encapsulation of the dose by manual spreading of the formulated powder in relation to the flow characteristics and dose of the compounding formulas. The selection of the 6 pharmaceutical products was based on dose, flow and existence of a validated method of analysis by UV spectroscopy. The validation process consisted of the analysis of average weight, uniformity of dose and content of five batches of each product prepared by two handlers. A written operating procedure was prepared for the method of manual encapsulation by spreading, for capsules of 500 mg metformine (MTF), 250 mg paracetamol (PCT), 200 mg ketoconazole (CTZ), 150mg nimesulide (NIM), 20 mg riboflavin (RIB) and 5mg glibenclamide (GLB). The procedure was validated for compounding the products MTF, PCT, CTZ, NIM and RIB, but not for the product GLB, as 4 lots were rejected in the test for uniformity of content. The results lead us to conclude that, for drug doses above 20 mg (with good or bad flow), this filling procedure is less susceptible to failure. The same is not true for drugs with doses ≤ 5 mg, showing that the smaller the dose, the harder it is to produce a capsule in the correct dose. It was also observed that the handler interferes with the quality of the capsules compounded, according to official pharmaceutical criteria...


Asunto(s)
Composición de Medicamentos , Preparaciones Farmacéuticas , Control de Calidad , Cápsulas
12.
Acta odontol. venez ; 52(3)2014. ilus
Artículo en Español | LILACS | ID: lil-778003

RESUMEN

Las placas de ateroma son conformadas por depósitos de lípidos en las camadas más profundas de las arterias y que siendo estructuras calcificadas pueden ser vistas en radiografías panorámicas. Su aspecto radiográfico debe ser diferenciado de las imágenes que pertenecen a diversas estructuras anatómicas y patológicas radiopacas, puesto que en dicho examen es posible observar asimismo otros hallazgos radiográficos en región cervical. Calcificaciones más a menudo descriptas en la literatura y que consisten en diagnóstico diferencial para las placas ateromatosas son el hueso hioides, cartílago tritícea, el cuerno superior de calcificación del cartílago tiroides calcificada, la epiglotis, los ganglios linfáticos calcificados, los flebolitos, los submaxilares de glándulas salivales y los tonsiolitos. Este estudio tiene como objetivo realizar una revisión de la literatura relativa a las placas ateromatosas y su diferencial diagnóstico con el fin de orientar mejor al dentista en la interpretación de estas imágenes. De esta manera, permite el reenvío de la paciente a un tratamiento preventivo, contribuyendo al desarrollo de la salud pública...


The atheromatous plaques consist of deposits of fat in the inner layers of the arteries and as they are calcified, can be detected on panoramic radiographs. Its radiographic appearance should be differentiated from others anatomical and pathological radiopaque structures, since this examination can also detect other radiographic findings in the neck. The calcifications most frequently described in the literature between anatomical and pathological conditions, and which constitute the differential diagnosis for atheromatous plaques are the hyoid bone, cartilage triticeous, the superior horn of the calcified thyroid cartilage, epiglottis, calcified lymph nodes, the phleboliths, submandibular salivary gland sialoliths and tonsilloliths. This study aims to conduct a review of literature related to atheromatous plaques and their differential diagnoses in order to provide better guidance to the dentist in the interpretation of those images. Thus, the patient can properly receive an early treatment, contributing to the development of public health...


Asunto(s)
Humanos , Masculino , Femenino , Aterosclerosis/fisiopatología , Hueso Hioides/anatomía & histología , Placa Aterosclerótica , Radiografía Panorámica , Diagnóstico por Imagen , Enfermedades Vasculares Periféricas , Accidente Cerebrovascular
13.
Appl Radiat Isot ; 70(9): 2081-6, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22401938

RESUMEN

The activities of (177)Lu, (111)In and (123)I solutions have been absolutely determined using three different measurement methods. (177)Lu solution was standardized using the 4πß(PC)-γ(NaI) coincidence and 4πß(LS)-γ(NaI) live-timed anticoincidence methods. For the (111)In and (123)I solutions, besides these two mentioned methods, the coincidence sum-peak method was also applied. The measured activities results using these different methods are consistent within the evaluated experimental uncertainties demonstrating the equivalence of these methods. As an additional contribution to nuclear data, the half-lives have been determined using a well type IG12 ionization chamber.


Asunto(s)
Radioisótopos/análisis , Radioisótopos/normas , Radiometría/instrumentación , Radiometría/normas , Semivida , Internacionalidad , Dosis de Radiación , Radioisótopos/química , Estándares de Referencia , Valores de Referencia
14.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;45(2): 118-124, Feb. 2012. ilus, tab
Artículo en Inglés | LILACS | ID: lil-614572

RESUMEN

Seed coat is a specialized maternal tissue that interfaces the embryo and the external environment during embryogenesis, dormancy and germination. In addition, it is the first defensive barrier against penetration by pathogens and herbivores. Here we show that Albizia lebbeck seed coat dramatically compromises the oviposition, eclosion and development of the bruchid Callosobruchus maculatus. Dietary supplementation of bruchid larvae with A. lebbeck seed coat flour causes severe weight loss and reduces survival. By means of protein purification, mass spectrometry and bioinformatic analyses, we show that chitin-binding vicilins are the main source of A. lebbeck tegumental toxicity to C. maculatus. At concentrations as low as 0.1 percent, A. lebbeck vicilins reduce larval mass from 8.1 ± 1.7 (mass of control larvae) to 1.8 ± 0.5 mg, which corresponds to a decrease of 78 percent. Seed coat toxicity constitutes an efficient defense mechanism, hindering insect predation and preventing embryo damage. We hypothesize that A. lebbeck vicilins are good candidates for the genetic transformation of crop legumes to enhance resistance to bruchid predation.


Asunto(s)
Animales , Femenino , Albizzia/química , Escarabajos/efectos de los fármacos , Proteínas de Almacenamiento de Semillas/toxicidad , Semillas/química , Larva/efectos de los fármacos
15.
Braz J Med Biol Res ; 45(2): 118-24, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22267002

RESUMEN

Seed coat is a specialized maternal tissue that interfaces the embryo and the external environment during embryogenesis, dormancy and germination. In addition, it is the first defensive barrier against penetration by pathogens and herbivores. Here we show that Albizia lebbeck seed coat dramatically compromises the oviposition, eclosion and development of the bruchid Callosobruchus maculatus. Dietary supplementation of bruchid larvae with A. lebbeck seed coat flour causes severe weight loss and reduces survival. By means of protein purification, mass spectrometry and bioinformatic analyses, we show that chitin-binding vicilins are the main source of A. lebbeck tegumental toxicity to C. maculatus. At concentrations as low as 0.1%, A. lebbeck vicilins reduce larval mass from 8.1 ± 1.7 (mass of control larvae) to 1.8 ± 0.5 mg, which corresponds to a decrease of 78%. Seed coat toxicity constitutes an efficient defense mechanism, hindering insect predation and preventing embryo damage. We hypothesize that A. lebbeck vicilins are good candidates for the genetic transformation of crop legumes to enhance resistance to bruchid predation.


Asunto(s)
Albizzia/química , Escarabajos/efectos de los fármacos , Proteínas de Almacenamiento de Semillas/toxicidad , Semillas/química , Animales , Femenino , Larva/efectos de los fármacos
16.
Braz J Med Biol Res ; 39(11): 1435-44, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17146556

RESUMEN

Evidence based on immunological cross-reactivity and anti-diabetic properties has suggested the presence of insulin-like peptides in plants. The objective of the present study was to investigate the presence of insulin-like proteins in the leaves of Bauhinia variegata ("pata-de-vaca", "mororó"), a plant widely utilized in popular medicine as an anti-diabetic agent. We show that an insulin-like protein was present in the leaves of this plant. A chloroplast protein with a molecular mass similar to that of bovine insulin was extracted from 2-mm thick 15% SDS-PAGE gels and fractionated with a 2 x 24 cm Sephadex G-50 column. The activity of this insulin-like protein (0.48 mg/mL) on serum glucose levels of four-week-old Swiss albino (CF1) diabetic mice was similar to that of commercial swine insulin used as control. Further characterization of this molecule by reverse-phase hydrophobic HPLC chromatographic analysis as well as its antidiabetic activity on alloxan-induced mice showed that it has insulin-like properties. Immunolocalization of the insulin-like protein in the leaves of B. variegata was performed by transmission electron microscopy using a polyclonal anti-insulin human antibody. Localization in the leaf blades revealed that the insulin-like protein is present mainly in chloroplasts where it is also found associated with crystals which may be calcium oxalate. The presence of an insulin-like protein in chloroplasts may indicate its involvement in carbohydrate metabolism. This finding has strengthened our previous results and suggests that insulin-signaling pathways have been conserved through evolution.


Asunto(s)
Bauhinia/química , Cloroplastos/química , Diabetes Mellitus Experimental/tratamiento farmacológico , Hipoglucemiantes/aislamiento & purificación , Proteínas de Unión a Factor de Crecimiento Similar a la Insulina/aislamiento & purificación , Hojas de la Planta/química , Animales , Autoanticuerpos/sangre , Bauhinia/citología , Bovinos , Cloroplastos/ultraestructura , Cromatografía Líquida de Alta Presión , Electroforesis en Gel de Poliacrilamida , Hipoglucemiantes/uso terapéutico , Inmunoglobulina G/sangre , Proteínas de Unión a Factor de Crecimiento Similar a la Insulina/uso terapéutico , Ratones , Microscopía Electrónica de Transmisión , Hojas de la Planta/citología
17.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;39(11): 1435-1444, Nov. 2006. ilus, graf
Artículo en Inglés | LILACS | ID: lil-437826

RESUMEN

Evidence based on immunological cross-reactivity and anti-diabetic properties has suggested the presence of insulin-like peptides in plants. The objective of the present study was to investigate the presence of insulin-like proteins in the leaves of Bauhinia variegata ("pata-de-vaca", "mororó"), a plant widely utilized in popular medicine as an anti-diabetic agent. We show that an insulin-like protein was present in the leaves of this plant. A chloroplast protein with a molecular mass similar to that of bovine insulin was extracted from 2-mm thick 15 percent SDS-PAGE gels and fractionated with a 2 x 24 cm Sephadex G-50 column. The activity of this insulin-like protein (0.48 mg/mL) on serum glucose levels of four-week-old Swiss albino (CF1) diabetic mice was similar to that of commercial swine insulin used as control. Further characterization of this molecule by reverse-phase hydrophobic HPLC chromatographic analysis as well as its antidiabetic activity on alloxan-induced mice showed that it has insulin-like properties. Immunolocalization of the insulin-like protein in the leaves of B. variegata was performed by transmission electron microscopy using a polyclonal anti-insulin human antibody. Localization in the leaf blades revealed that the insulin-like protein is present mainly in chloroplasts where it is also found associated with crystals which may be calcium oxalate. The presence of an insulin-like protein in chloroplasts may indicate its involvement in carbohydrate metabolism. This finding has strengthened our previous results and suggests that insulin-signaling pathways have been conserved through evolution.


Asunto(s)
Animales , Bovinos , Ratones , Bauhinia/química , Cloroplastos/química , Diabetes Mellitus Experimental/tratamiento farmacológico , Hipoglucemiantes/aislamiento & purificación , Proteínas de Unión a Factor de Crecimiento Similar a la Insulina/aislamiento & purificación , Hojas de la Planta/química , Autoanticuerpos/sangre , Bauhinia/citología , Cromatografía Líquida de Alta Presión , Cloroplastos/ultraestructura , Electroforesis en Gel de Poliacrilamida , Hipoglucemiantes/uso terapéutico , Inmunoglobulina G/sangre , Proteínas de Unión a Factor de Crecimiento Similar a la Insulina/uso terapéutico , Microscopía Electrónica de Transmisión , Hojas de la Planta/citología
18.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;36(9): 1167-1173, Sept. 2003. ilus, tab, graf
Artículo en Inglés | LILACS | ID: lil-342857

RESUMEN

Since the discovery of bovine insulin in plants, much effort has been devoted to the characterization of these proteins and elucidation of their functions. We report here the isolation of a protein with similar molecular mass and same amino acid sequence to bovine insulin from developing fruits of cowpea (Vigna unguiculata) genotype Epace 10. Insulin was measured by ELISA using an anti-human insulin antibody and was detected both in empty pods and seed coats but not in the embryo. The highest concentrations (about 0.5 ng/æg of protein) of the protein were detected in seed coats at 16 and 18 days after pollination, and the values were 1.6 to 4.0 times higher than those found for isolated pods tested on any day. N-terminal amino acid sequencing of insulin was performed on the protein purified by C4-HPLC. The significance of the presence of insulin in these plant tissues is not fully understood but we speculate that it may be involved in the transport of carbohydrate to the fruit


Asunto(s)
Animales , Bovinos , Insulina , Proteínas de Plantas , Plantas , Homología de Secuencia de Aminoácido , Western Blotting , Cromatografía Líquida de Alta Presión , Electroforesis en Gel de Poliacrilamida , Ensayo de Inmunoadsorción Enzimática , Insulina , Peso Molecular , Proteínas de Plantas , Plantas
19.
Braz J Med Biol Res ; 36(9): 1167-73, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12937781

RESUMEN

Since the discovery of bovine insulin in plants, much effort has been devoted to the characterization of these proteins and elucidation of their functions. We report here the isolation of a protein with similar molecular mass and same amino acid sequence to bovine insulin from developing fruits of cowpea (Vigna unguiculata) genotype Epace 10. Insulin was measured by ELISA using an anti-human insulin antibody and was detected both in empty pods and seed coats but not in the embryo. The highest concentrations (about 0.5 ng/micro g of protein) of the protein were detected in seed coats at 16 and 18 days after pollination, and the values were 1.6 to 4.0 times higher than those found for isolated pods tested on any day. N-terminal amino acid sequencing of insulin was performed on the protein purified by C4-HPLC. The significance of the presence of insulin in these plant tissues is not fully understood but we speculate that it may be involved in the transport of carbohydrate to the fruit.


Asunto(s)
Fabaceae/química , Insulina/análisis , Proteínas de Plantas/análisis , Homología de Secuencia de Aminoácido , Animales , Western Blotting , Bovinos , Cromatografía Líquida de Alta Presión , Electroforesis en Gel de Poliacrilamida , Ensayo de Inmunoadsorción Enzimática , Fabaceae/genética , Insulina/genética , Peso Molecular , Proteínas de Plantas/genética
20.
Braz J Med Biol Res ; 35(3): 297-303, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11887207

RESUMEN

We report the detection of insulin-like antigens in a large range of species utilizing a modified ELISA plate assay and Western blotting. We tested the leaves or aerial parts of species of Rhodophyta (red alga), Bryophyta (mosses), Psilophyta (whisk ferns), Lycopodophyta (club mosses), Sphenopsida (horsetails), gymnosperms, and angiosperms, including monocots and dicots. We also studied species of fungi and a cyanobacterium, Spirulina maxima. The wide distribution of insulin-like antigens, which in some cases present the same electrophoretic mobility as bovine insulin, together with results recently published by us on the amino acid sequence of an insulin isolated from the seed coat of jack bean (Canavalia ensiformis) and from the developing fruits of cowpea (Vigna unguiculata), suggests that pathways depending on this hormone have been conserved through evolution.


Asunto(s)
Hongos/química , Insulina/análisis , Proteínas de Plantas/análisis , Proteínas/análisis , Rhodophyta/química , Animales , Proteínas Bacterianas/análisis , Proteínas Bacterianas/genética , Western Blotting , Bovinos , Cianobacterias/química , Electroforesis en Gel de Poliacrilamida , Ensayo de Inmunoadsorción Enzimática , Hongos/genética , Peso Molecular , Proteínas de Plantas/genética , Rhodophyta/genética
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