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Electron. j. biotechnol ; 41: 56-59, sept. 2019. tab, graf
Article in English | LILACS | ID: biblio-1087166


Background: Chinese hamster ovary (CHO) cells are the most dependable mammalian cells for the production of recombinant proteins. Replication-incompetent retroviral vector (retrovector) is an efficient tool to generate stable cell lines. Multiple copies of integrated genes by retrovector transduction results in improved recombinant protein yield. HEK-293 and their genetic derivatives are principal cells for retrovector production. Retrovectors packaged in HEK-293 cells pose a risk of infectious agent transmission, such as viruses and mycoplasmas, from serum and packaging cells. Results: In this report, retrovectors were packaged in CHO cells cultured in chemically defined (CD) media. The retrovectors were then used to transduce CHO cells. This method can block potential transmission of infectious agents from serum and packaging cells. With this method, we generated glucagon-like protein-1 Fc fusion protein (GLP-1-Fc) stable expression CHO cell lines. Productivity of GLP-1-Fc can reach 3.15 g/L. The GLP-1-Fc protein produced by this method has comparable bioactivity to that of dulaglutide (Trulicity). These stable cell lines retain 95­100% of productivity after 40 days of continuous culture (~48­56 generations). Conclusions: Suspension CHO cells are clean, safe, and reliable cells for retrovector packaging. Retrovectors packaged from this system could be used to generate CHO stable cell lines for recombinant protein expression.

Retroviridae , Recombinant Proteins/metabolism , CHO Cells/metabolism , Immunoglobulin Fc Fragments , Cell Line , Chromatography, Gel/methods , Disease Vectors , Glucagon-Like Peptide 1 , Tandem Mass Spectrometry , Batch Cell Culture Techniques
Chinese Journal of Biotechnology ; (12): 1441-1452, 2019.
Article in Chinese | WPRIM | ID: wpr-771785


We developed a pre-treatment method to remove interfering substances during quantification of 146S antigens in foot-and-mouth disease (FMD) vaccines by high performance size exclusion chromatography (HPSEC). Three methods, including ultracentrifugation, PEG precipitation and nuclease digestion, were optimized and compared for removal efficiency of the interfering impurities in FMD vaccines. Under optimized conditions, the 146S contents in two batches of FMD vaccines were determined to be 7.1 and 7.6 μg/mL by ultracentrifugation, 9.7 and 10.4 μg/mL by PEG precipitation, and 10.5 and 10.4 μg/mL by nuclease digestion. The optimal condition for nuclease digestion using Benzonase determined by response surface method was as follows: appending Benzonase into 200 μL of antigen phase to a final concentration of 421 U/mL and incubating at 25.1 °C for 1.29 h. This method has advantages including efficient removal of the interfering impurities, fast processing speed, and mild operating conditions. Then 12 bathes of FMD vaccines with different serotypes produced by 4 manufacturers were tested to verify the established treatment method. Results showed the method was applicable to various FMD vaccines with good reproducibility (RSD<5.3%, n=3). The developed method removed interference from impurities during quantification of 146S, and therefore would broaden the application of HPSEC in vaccine quality control and ensure the accuracy and reliability.

Animals , Chromatography, Gel , Foot-and-Mouth Disease , Foot-and-Mouth Disease Virus , Reproducibility of Results , Viral Vaccines
Chinese Journal of Biotechnology ; (12): 159-168, 2019.
Article in Chinese | WPRIM | ID: wpr-771390


Two proteins of similar molecular weight (named as ASPR-C-1 and ASPR-C-2) from the crude drug of Angelica sinensis were purified and characterized by 80% ammonium sulfate precipitation, Sephadex G-50 gel filtration chromatography, and DEAE-Sepharose anion exchange chromatography. The molecular weight of ASPR-C-1 and ASPR-C-2 on SDS-PAGE was 17.33 kDa and 17.18 kDa, respectively. They were mainly monomeric in solution, but partially formed dimers and they were glycoproteins with glycosyl content of 2.6% and 8.2%, respectively. Both ASPR-C-1 and ASPR-C-2 were identified to be members of pathogenesis-related 10 family of proteins by matrix-assisted laser desorption ionization time-of-flight mass spectrometry and have ribonuclease activities with the specific activity of 73.60 U/mg and 146.76 U/mg, respectively. The optimum pH of the two isoforms was similar, at about 5.6, while their optimum temperatures were different. The optimum temperature of ASPR-C-1 was 50 ℃, and that of ASPR-C-2 was 60 ℃. Both isoforms presented highest thermal stability at 60 ℃. However, ASPR-C-2 was more thermotolerant than ASPR-C-1. The latter was rapidly inactivated and retained only about 20% residual activity while the former still maintained about 80% of its original activity at a higher treatment temperature (80 to 100 ℃). In addition, Fe²⁺ had an activating effect on the ribonuclease activities of two isoforms while Ca²⁺, Mg²⁺, Zn²⁺, Mn²⁺, Ag⁺, Cu²⁺, EDTA (Elhylene diamine tetraacetic acid), dithiothreitol and sodium dodecylsulphate showed different degrees of inhibition of the enzyme activities. Our findings provide a foundation for further research on the biological function of PR-10 protein from Angelica sinensis.

Angelica sinensis , Chromatography, Gel , Chromatography, Ion Exchange , Electrophoresis, Polyacrylamide Gel , Enzyme Stability , Hydrogen-Ion Concentration , Kinetics , Molecular Weight , Protein Isoforms , Temperature
São Paulo; s.n; s.n; 2018. 81 p. graf, tab, ilus.
Thesis in Portuguese | LILACS | ID: biblio-909421


A L-Asparaginase (ASNase) é um importante agente quimioterapêutico utilizado para o tratamento da leucemia linfoblástica aguda (ALL) há mais de 40 anos. No entanto, devido à origem biológica da ASNase, enzima produzida por Escherichia coli, problemas como a imunogenicidade e baixa meia vida-plasmática devem ser considerados. Com o objetivo de minimizar essas desvantagens, várias ASNases homólogas bem como formulações de ASNase de E. coli foram investigadas. Nenhuma das formulações desenvolvidas, entretanto, foi capaz de resolver definitivamente esses problemas associados à sua origem. Nesse sentido, considerando os recentes avanços na ciência de polímeros com a possibilidade do obtenção de vesículas poliméricas usando copolímeros, este trabalho concentrou-se no desenvolvimento de polimerossomos de poli(etileno glicol)-b-poli(ε-caprolactona) (PEG-PCL) para encapsular a ASNase. Diversas condições experimentais foram investigadas e, ao final, os polimerossomos foram produzidos pela técnica de hidratação do filme polimérico utilizando a centrifugação como técnica de pós-filme para remoção de copolímero precipitado, produzindo assim vesículas polímericas de 120 a 200nm com PDI de aproximadamente 0,250. A eficiência de encapsulação da ASNase, utilizando as metodologias de centrifugação ou cromatografia de exclusão molecular, revelou taxas de encapsulação de 20-25% e 1 a 7%, repectivamente. Esses resultados apontam a importância de se determinar a eficiência de encapsulação por cromatografia de exclusão molecular ou método direto no caso de nanoestruturas auto-agregadas formadas por copolímeros, devido a valores superestimados com o emprego da centrifugação. Ainda que estudos complementares se façam necessários para liberação da enzima encapsulada ou penetração da L-asparagina nas vesículas, nossos resultados demonstram o potencial de polimerossomos para veiculação de ASNase, bem como de outras proteínas terapêuticas

L-Asparaginase (ASNase) is an important chemotherapeutic agent used for the treatment of acute lymphoblastic leukemia (ALL) for more than 40 years. However, due to the biological origin of ASNase (produced by Escherichia coli) some drawbacks such as immunogenicity and low plasma half life are present. In order to minimize the disadvantages, several ASNases proteoforms and formulations of E. coli ASNase were investigated. However, none of this formulations completely solved the main drawbacks of ASNase. In this sense, considering the recents advances in polymers science with the possibility to develop polymeric vesicles using copolymers, this work aimed at the development of poly(ethylene glycol)-b-poly(ε-caprolactone) (PEG-PCL) vesicles to encapsulate ASNase. Different experimental conditions were investigated and, the final polymersomes formulation was prepared by film hydratation using centrifugation as a post-film technique to remove the bulky coplymer. Polymeric vesicles of 120 to 200nm with PDI of approximately, 0.250 were obtained. The encapsulation efficiency of ASNase was determined indirectly by centrifugation and directly by size exclusion chromatography, resulting in encapsulation rates of 20-25% and 1 to 7%, respectively. These results indicate the importance of determining the efficiency of encapsulation by size exclusion chromatography or direct method in the case of self-aggregated nanostructures formed by copolymers, due to values overestimated with the use of centrifugation. Our results point to the potential of polymersomes for ASNase delivery, as well as other therapeutic proteins. Nonetheless, complimentary studies are still necessary for ASNase release or L-asparagine penetration into the vesicles

Asparaginase/analysis , Chromatography, Gel/instrumentation , Blister , Capsules , Escherichia coli/classification
Electron. j. biotechnol ; 29: 7-12, sept. 2017. ilus, graf, tab
Article in English | LILACS | ID: biblio-1016095


Background: DegP is a serine protease that specifically cleaves and refolds unfolding proteins in the periplasmic space of the cells. To date, there is no information regarding DegP from halophilic bacteria. Chromohalobacter salexigens BKL5 is a moderately halophilic bacterium that has the ability to grow in a media containing more than 15% salt. Therefore, the objectives of this work were to clone and overexpress DegP-encoding gene from C. salexigens BKL5 and characterize its biochemical properties. Results: DegP-encoding gene was overexpressed in Escherichia coli BL21(DE3) CodonPlus in an active form. SDS-PAGE analysis showed that the molecular weight of the recombinant DegP was 45 kDa. Size-exclusion chromatography analysis suggested that recombinant DegP was present in two multimeric states, hexameric and dodecameric, with molecular weights of 297.9 and 579.12 kDa, respectively. Both conformations were enzymatically active when casein was used as substrate for enzymatic assay. Circular dichroism analysis showed that recombinant DegP was composed of 0.21­0.29 helical content, which was comparable to the helical content in the crystal structure of E. coli DegP. The basic/acidic residue ratio of recombinant DegP was 0.56, which was slightly higher than that of DegP from extreme halophiles (average, 0.45) but significantly lower than that of DegP from nonhalophiles (average, 0.94). Conclusions: Recombinant DegP from C. salexigens BKL5 showed proteolytic activity when ß-casein was used as a substrate. In silico analysis indicated that recombinant DegP had characteristics similar to those of halophilic proteins depending on its amino acid composition.

Serine Endopeptidases/genetics , Periplasmic Proteins/genetics , Chromohalobacter/enzymology , Proteolysis , Heat-Shock Proteins/genetics , Recombinant Proteins , Serine Endopeptidases/metabolism , Caseins , Chromatography, Gel , Circular Dichroism , Cloning, Molecular , Periplasmic Proteins/metabolism , Electrophoresis, Polyacrylamide Gel , Escherichia coli , Salinity , Chromohalobacter/genetics , Heat-Shock Proteins/metabolism , Molecular Weight
Arq. bras. oftalmol ; 80(2): 108-113, Mar.-Apr. 2017. tab, graf
Article in English | LILACS | ID: biblio-838784


ABSTRACT Purpose: Avastin® (bevacizumab) is an anti-vascular endothelial growth factor (VEGF) monoclonal antibody given as an off-label drug by intravitreal administration for treatment of ocular diseases. The drug's clinical application and its cost-benefit profile has generated demand for its division into single-use vials to meet the low volume and low-cost doses necessary for intraocular administration. However, the safety of compounding the drug in single-use vials is still under discussion. In this study, the stability and efficacy of Avastin® repacked in individual single-use glass vials and glass ampoules by external compounding pharmacies were evaluated. Methods: Polyacrylamide gel electrophoresis (PAGE), size-exclusion chromatography (SEC), dynamic light scattering (DLS), and turbidimetry were selected to detect the formation of aggregates of various sizes. Changes in bevacizumab biological efficacy were investigated by using an enzyme-linked immunosorbent assay (ELISA). Results: Repacked and reference bevacizumab showed similar results when analyzed by PAGE. By SEC, a slight increase in high molecular weight aggregates and a reduction in bevacizumab monomers were observed in the products of the three compounding pharmacies relative to those in the reference bevacizumab. A comparison of repacked and reference SEC chromatograms showed that the mean monomer loss was ≤1% for all compounding pharmacies. Protein aggregates in the nanometer- and micrometer-size ranges were not detected by DLS and turbidimetry. In the efficacy assay, the biological function of repacked bevacizumab was preserved, with <3% loss of VEGF binding capacity relative to that of the reference. Conclusion: The results showed that bevacizumab remained stable after compounding in ampoules and single-use glass vials; no significant aggregation, fragmentation, or loss of biological activity was observed.

RESUMO Objetivos: Avastin® (bevacizumabe) é um anticorpo monoclonal inibidor do fator de crescimento endotelial de vasos (VEGF) utilizado "off-label" por meio de administração intravítrea para o tratamento de doenças oculares. A sua aplicação clínica associada ao custo-benefício do medicamento gerou uma demanda para seu fracionamento em frascos de dose única para utilização pela via intraocular. No entanto, a segurança do fracionamento do anticorpo em frascos de dose única ainda é alvo de discussão. Neste trabalho, a estabilidade e a eficácia do Avastin® fracionado em frascos ou ampolas de vidro de dose unitária por farmácias de manipulação do mercado foram avaliadas. Métodos: As técnicas de eletroforese em gel de poliacrilamida (PAGE), cromatografia por exclusão de tamanho (SEC), espalhamento dinâmico da luz (DLS) e turbidimetria foram empregadas para avaliar a formação de agregados de diferentes tamanhos. Alterações na atividade biológica do bevacizumabe foram estudadas utilizando ELISA. Resultados: Amostras referência e do bevacizumabe fracionado apresentaram resultados semelhantes quando analisado por gel de poliacrilamida. Por cromatografia por exclusão de tamanho, um pequeno aumento na quantidade de agregados de alta massa molar seguido de uma redução nos monômeros do bevacizumabe foram observados para as amostras das três farmácias de manipulação quando comparado ao referência. A comparação dos cromatogramas mostrou uma quantidade de redução do monômero inferior a 1% para todas as amostras fracionadas. Por espalhamento dinâmico da luz e turbidimetria, não foram detectados agregados de proteína na faixa de tamanho de micrômetro e nanômetro. No ensaio de eficácia, o bevacizumabe fracionado preservou sua função biológica pois apresentou menos de 3% de perda na capacidade de ligação ao VEGF quando comparado ao referência. Conclusão: Este estudo sugere que o bevacizumabe se mantem estável após fracionamento em ampolas e frascos de vidro de dose unitária pois não foram observadas agregação e/ou fragmentação de proteínas e perda de atividade biológica em quan tidades significativas.

Quality Control , Angiogenesis Inhibitors/chemistry , Drug Packaging , Bevacizumab/chemistry , Enzyme-Linked Immunosorbent Assay/methods , Chromatography, Gel/methods , Angiogenesis Inhibitors/analysis , Vascular Endothelial Growth Factor A/analysis , Drug Stability , Electrophoresis, Polyacrylamide Gel/methods , Intravitreal Injections , Bevacizumab/analysis , Dynamic Light Scattering/methods , Molecular Weight , Nephelometry and Turbidimetry/methods
Chinese Journal of Biotechnology ; (12): 1727-1734, 2016.
Article in Chinese | WPRIM | ID: wpr-243685


In order to prepare antioxidant peptide through hydrolyzing low-value protein resources with bacterial extracellular proteases and to discover novel proteases, crude extracellular protease from Pseudoalteromonas sp. SHK1-2 was obtained through fermentation which was used to hydrolyze collagen extracted from Cirrhinus molitorella skin. Small peptide fraction was isolated from hydrolysate by ultrafiltration and Sephadex LH-20 size exclusion chromatography and showed 1, 1-diphenyl-2-picrylhydrazyl radical scavenging activity (35.6%±7%), oxygen radical absorbance capacity and inhibition of DNA oxidation damage. The molecule weight was 776.2 Da, and amino acid sequence was Thr-Ala-Gly-His-Pro- Gly-Thr-His through liquid chromatography mass spectrum. Our findings suggest that peptide obtained from low-value protein of fish waste by hydrolysis with bacterial protease has antioxidant activity.

Amino Acid Sequence , Animals , Antioxidants , Chemistry , Chromatography, Gel , Collagen , Chemistry , Cyprinidae , Dextrans , Hydrolysis , Oxidation-Reduction , Peptide Hydrolases , Peptides , Chemistry , Skin , Chemistry
Braz. j. microbiol ; 46(1): 251-260, 05/2015. tab, graf
Article in English | LILACS | ID: lil-748253


An Aspergillus niger UFV-1 phytase was characterized and made available for industrial application. The enzyme was purified via ultrafiltration followed by acid precipitation, ion exchange and gel filtration chromatography. This protein exhibited a molecular mass of 161 kDa in gel filtration and 81 kDa in sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), indicating that it may be a dimer. It presented an optimum temperature of 60 °C and optimum pH of 2.0. The KM for sodium phytate hydrolysis was 30.9 mM, while the kcat and kcat/KM were 1.46 ×105 s−1 and 4.7 × 106 s−1.M−1, respectively. The purified phytase exhibited broad specificity on a range of phosphorylated compounds, presenting activity on sodium phytate, p-NPP, 2- naphthylphosphate, 1- naphthylphosphate, ATP, phenyl-phosphate, glucose-6-phosphate, calcium phytate and other substrates. Enzymatic activity was slightly inhibited by Mg2+, Cd2+, K+ and Ca2+, and it was drastically inhibited by F−. The enzyme displayed high thermostability, retaining more than 90% activity at 60 °C during 120 h and displayed a t1/2 of 94.5 h and 6.2 h at 70 °C and 80 °C, respectively. The enzyme demonstrated strong resistance toward pepsin and trypsin, and it retained more than 90% residual activity for both enzymes after 1 h treatment. Additionally, the enzyme efficiently hydrolyzed phytate in livestock feed, liberating 15.3 μmol phosphate/mL after 2.5 h of treatment.

/isolation & purification , /metabolism , Aspergillus niger/enzymology , /chemistry , Chemical Precipitation , Chromatography, Gel , Chromatography, Ion Exchange , Electrophoresis, Polyacrylamide Gel , Enzyme Stability , Enzyme Inhibitors/analysis , Hydrogen-Ion Concentration , Hydrolysis , Kinetics , Molecular Weight , Protein Multimerization , Proteolysis , Peptide Hydrolases/metabolism , Phytic Acid/metabolism , Substrate Specificity , Temperature , Ultrafiltration
Braz. j. microbiol ; 46(1): 285-292, 05/2015. tab, graf
Article in English | LILACS | ID: lil-748256


Aspergillus flavus was isolated from soil and exhibited laccase activity under both constitutive and copper induced conditions. Spiking the medium with 1 mM copper sulfate resulted in an increase in the activity which reached 51.84 U/mL, a distinctive protein band was detected at 60 kDa. The extracellular enzyme was purified 81 fold using gel filtration chromatography and resulted in two different laccase fractions L1 and L2, the latter had a higher enzymatic activity which reached 79.57 U/mL and specific activity of 64.17 U/μg protein. The analysis of the spectrum of the L2 fraction showed a shoulder at 330 nm which is characteristic for T2/T3 copper centers; both copper and zinc were detected suggesting that this is an unconventional white laccase. Primers of laccase gene were designed and synthesized to recover specific gene from A. flavus. Sequence analysis indicated putative laccase (Genbank ID: JF683612) at the amino acid level suggesting a close identity to laccases from other genera containing the copper binding site. Decolorization of textile waste water under different conditions showed possible application in bioremediation within a short period of time. The effect of copper on A. flavus was concentration dependent.

Aspergillus flavus/drug effects , Aspergillus flavus/enzymology , Copper/metabolism , Gene Expression Regulation, Enzymologic/drug effects , Laccase/biosynthesis , Transcriptional Activation/drug effects , Aspergillus flavus/genetics , Aspergillus flavus/isolation & purification , Chromatography, Gel , Culture Media/chemistry , DNA, Fungal/genetics , Electrophoresis, Polyacrylamide Gel , Industrial Waste , Laccase/chemistry , Laccase/isolation & purification , Molecular Sequence Data , Molecular Weight , Sequence Analysis, DNA , Sequence Homology, Amino Acid , Soil Microbiology , Spectrum Analysis , Water Purification
Salud pública Méx ; 57(1): 38-49, ene.-feb. 2015. ilus, tab
Article in Spanish | LILACS | ID: lil-736460


Objetivo. Comparar la salud, uso de servicios sanitarios y necesidad insatisfecha de atención médica (NIAM) entre inmigrantes y nativos del sureste español. Material y métodos. Estudio transversal de dos muestras representativas de población: inmigrante (n=1150) y nativa (n=1303; Encuesta Nacional de Salud). Se creó una única base de datos con ponderación específica para cada muestra y se estimaron razones de prevalencia (RP) mediante regresión multivariante. Resultados. Marroquíes, ecuatorianos y europeos del este (EE) declararon peor salud que los nativos (RPs [IC95%]: 2.45 [1.91-3.15]; 1.51 [1.28-1.79] y 1.44 [1.08-1.93], respectivamente). Los inmigrantes hicieron mayor uso de las urgencias (excepto EE) y consumieron menos fármacos. Los marroquíes mostraron la mayor diferencia en la frecuencia de NIAM (RP [IC95%]: 12.20 [5.25-28.37]), principalmente por razones laborales (46%). Conclusiones. La salud y el uso de servicios sanitarios difirieron significativamente entre inmigrantes y nativos. Destaca la NIAM alta en marroquíes por causa laboral.

Objective. To compare the self-perceived health, use of health services and unmet need for health care (UNHC) among immigrants and native populations of Southeast Spain. Materials and methods. Cross-sectional study of two representative samples of 1150 immigrants, and 1303 native participants from the National Health Survey. A single database was created with specific weights for each sample, and prevalence ratios (PR) were estimated by multivariate regression. Results. Moroccans, Ecuadorians and Eastern Europeans (EE) reported poorer health than the native population (PRs [CI95%]: 2.45 [1.91-3.15]; 1.51 [1.28-1.79] and 1.44 [1.08-1.93], respectively). Immigrants made greater use of emergencies that natives (except for EE) and had lower use of medication. Moroccan showed the greatest difference in the frequency of UNHC (PR [CI95%]:12.20 [5.25 - 28.37]), mainly because of working limitations (46%). Conclusions. The health status and use of health services among immigrants differ significantly from those of natives. Results highlight the higher frequency of UNHC among immigrants, especially high in Moroccans.

Animals , Humans , Cysteine Endopeptidases/isolation & purification , Taenia solium/enzymology , Chromatography, Gel , Chromatography, Ion Exchange , Collagen/metabolism , Cysteine Endopeptidases/chemistry , Cysteine Endopeptidases/metabolism , Cysteine Proteinase Inhibitors/pharmacology , Immunoglobulin G/metabolism , Iodoacetic Acid/pharmacology , Leucine/analogs & derivatives , Leucine/pharmacology , Serum Albumin, Bovine/metabolism
Ciênc. saúde coletiva ; 20(1): 145-153, 01/2015.
Article in English | BDS, LILACS | ID: lil-733130


In this paper, the question of Brazil's insertion today as a country with the characteristics of modern consumer societies is discussed, focusing on the commercialization of the health sector, the segmentation of the health system and the contradictions of the rights to health care in the social context in question. Some research data on these issues broadcast in the National News Bulletins of Globo TV during the year of 2012 are presented, in which the high technology private hospital as a consumer icon, the underfunding of the public health system and the rejection of a poor and deprived Unified Health System are analyzed.

Discute-se aqui a nossa inserção como país, hoje, nas sociedades de consumo características da modernidade, enfocando a mercantilização na área da saúde, a segmentação do sistema de saúde e as contradições do direito à saúde no contexto social em questão. São apresentados dados de pesquisa sobre o tema no Jornal Nacional da Rede Globo de Televisão, durante o ano de 2012, na qual se analisa o hospital privado de alto padrão tecnológico como ícone de consumo, o subfinanciamento do sistema público de saúde e a rejeição de um Sistema Único de Saúde pobre e carente.

Azo Compounds/analysis , Chromatography, Gel/methods , Chromatography, High Pressure Liquid/methods , Spectrometry, Mass, Electrospray Ionization/methods , Spices/analysis , Tandem Mass Spectrometry/methods , Azo Compounds/chemistry , Capsicum/chemistry , Food Analysis/methods , Food Coloring Agents/analysis , Food Coloring Agents/chemistry , Molecular Structure , Naphthols/analysis , Naphthols/chemistry , Reproducibility of Results
Article in English | WPRIM | ID: wpr-812156


The polysaccharides from pumpkin fruit (PP) were obtained and purified by hot-water extraction, anion-exchange chromatography, and gel column chromatography. The physicochemical properties of PP were determined by gel filtration chromatography, gas chromatography, fourier transform infrared (FTIR) spectroscopy, and nuclear magnetic resonance (NMR) spectroscopy. Results indicated that the molecular weight of PP was about 23 kDa and PP was composed of D-Arabinose, D-Mannose, D-Glucose, and D-Galactose with a molar ratio of 1 : 7.79 : 70.32 : 7.05. FTIR and NMR spectra indicated that PP was the polysaccharide containing pyranose ring. Additionally, PP protected islets cells from streptozotocin (STZ) injury in vitro via increasing the levels of super-oxide dismutase (SOD) and malondialdehyde (MDA) and reducing the production of NO. The experiment of reverse transcriptase-polymerase chain reaction further proved that PP inhibited apoptosis via modulating the expression of Bax/Bcl-2 in STZ-damaged islet cells. In conclusion, PP could be explored as a novel agent for the treatment of diabetes mellitus.

Animals , Apoptosis , Chromatography, Gas , Chromatography, Gel , Cucurbita , Chemistry , Diabetes Mellitus, Experimental , Drug Therapy , Islets of Langerhans , Wounds and Injuries , Magnetic Resonance Spectroscopy , Malondialdehyde , Molecular Weight , Monosaccharides , Nitric Oxide , Polysaccharides , Chemistry , Pharmacology , Rats , Rats, Sprague-Dawley , Reverse Transcriptase Polymerase Chain Reaction , Spectroscopy, Fourier Transform Infrared , Superoxide Dismutase , bcl-2-Associated X Protein
Rev. bras. plantas med ; 16(4): 794-803, oct.-dic. 2014. graf, tab
Article in Portuguese | LILACS | ID: lil-729886


Este trabalho objetivou a purificação parcial, por precipitação com sulfato de amônio (SA) e cromatografia de filtração em gel (CFG), de compostos presentes no decocto de Adiantum capillus-veneris (avenca) eficientes na indução de fitoalexinas em mesocótilos de Sorghum bicolor sorgo. Decocto de A. capillus-veneris a 1% (peso seco/volume) foi precipitado com concentrações de SA variando de 0 a 100% (em intervalos de 20%), e essas frações foram submetidas à CFG. Para o decocto não precipitado foram obtidos nove picos proteicos e um pico glicídico com massas moleculares variando de 0,61 à 0,01 KDa. Para a precipitação fracionada obteve-se: na fração 0-20% dois picos proteicos (menores que 0,01 KDa) e dois glicídicos com concentração de açúcares variando de 4,1 a 17,5 µg mL-1; na fração 20-40% três picos proteicos (111,5 à 0,98 KDa) e cinco glicídicos (11,3 a 73,7 µg de açúcares mL-1); na fração 40-60% dois picos proteicos (111,5 à 0,09 KDa) e dois glicídicos (5,6 a 7, 5 µg de açúcares mL-1); na fração 60-80% seis picos proteicos (menores que 0,02 KDa) e dois glicídicos (16,5 a 51,3 µg de açúcares mL-1); e na fração 80-100% três picos proteicos (menores que 0,09 KDa). Mesocótilos de sorgo foram tratados com as frações provenientes da CFG, além do decocto a 1%, acibenzolar-S-metil (ASM) (125 mg L-1 do i.a. como eliciador de referência) e tampão fosfato de sódio 10 mM pH 6,0. O pico proteico II (0,09 KDa) do decocto não precipitado induziu fitoalexinas, 6,68% superior a ASM. Entre os precipitados, a fração 60-80% de SA induziu 76% mais que ASM. Dessa forma, pôde-se obter frações proteicas e/ou glicídicas indutoras de fitoalexinas em sorgo de maneira superior ao extrato (decocto) do qual é originária, indicando o potencial dessas moléculas para trabalhos futuros sobre indução de resistência.

This study aimed to partially purify the compounds present in decoction of Adiantum capillus-veneris, which are efficient in the induction of phytoalexins in sorghum mesocotyl, by ammonium sulphate (AS) fractionation and gel filtration chromatography (GFC). The decoction of A. capillus-veneris at 1% (weight/volume) was precipitated with AS at the concentration of 0-20%, 20-40%, 40-60%, 60-80% and 80-100%, and these fractions were subjected to GFC. For the decoction not precipitated with AS, nine protein peaks and one carbohydrate peak were obtained with molecular weights ranging from 0.61 to 0.01 KDa. For the AS precipitation, we obtained: for the fraction 0-20%, two protein peaks (0.01 KDa) and two carbohydrate peaks with concentration of sugars ranging from 4.1 to 17.5 µg of sugar mL-1; for the 20-40%, three protein peaks (0.98 to 111.5 KDa) and five carbohydrate peaks (11.3 to 73.7 µg sugar mL-1); for the 40-60%, two protein peaks (0.09 to 111.5 KDa) and two carbohydrate peaks (5.6 to 7.5 µg of sugar mL-1); for the 60-80%, six protein peaks (lower than 0.02 KDa) and two carbohydrate peaks (16.5 to 51.3 µg of sugar mL-1); and for the 80-100%, three protein peaks with molecular weight equivalent to 0.09 KDa. The sorghum mesocotyls were treated with GFC fractions, decoction (1%), acibenzolar-S-methyl (ASM) (125 mg L-1 a.i. as elicitor reference) and sodium phosphate buffer (10 mM, pH 6.0). The protein peak II (0.09 KDa) from the decoction not precipitated was effective in inducing phytoalexin, exceeding in 6.68% the ASM. Among the fractions, the one with 60-80% of AS increased in 76% the induction of phytoalexin compared to ASM. According to the results, we could obtain protein and/or carbohydrate fractions capable of inducing phytoalexins in sorghum better than the decoction from which they are derived from, showing the potential of these molecules for future research studies on the induction of resistance.

Adiantum/anatomy & histology , Ammonium Sulfate/pharmacology , Chromatography, Gel/methods , Defense Mechanisms , Plants, Medicinal/classification , Sorghum/anatomy & histology
Rev. bras. enferm ; 67(6): 957-964, Nov-Dec/2014.
Article in Portuguese | LILACS, BDENF | ID: lil-732825


Objetivo: identificar as necessidades e as preocupações prioritárias, manifestadas pelos pais no desempenho do seu papel, em três etapas do ciclo vital: adolescência, idade produtiva e idade madura. Metodologia: estudo exploratório com abordagem qualitativa, desenvolvido com quatorze pais residentes em um município no extremo sul do Brasil. Os dados foram coletados entre maio e agosto de 2011, por meio de entrevista em profundidade. Através da técnica da análise textual discursiva e da matriz construída com base na teoria bioecológica de Bronfenbrenner, foram construídas três categorias: Necessidades/preocupações do pai, geradas em sua relação com o mundo do trabalho; Necessidades/preocupações que emergem da relação de cuidado com os filhos e Preocupações dos pais com relação ao futuro dos filhos. Conclusão: identificou-se que a preocupação com o futuro dos filhos foi apontada por pais de todas as faixas-etárias investigadas. .

Objective: this study aimed to identify priority needs and concerns expressed by fathers in the performance of their role in three stages of the life cycle: adolescence, productive age, and mature age. Methodology: this is an exploratory study with a qualitative approach, conducted with fourteen fathers residing in a municipality in the extreme south of Brazil. The data were collected between May and August 2011 by means of the in-depth interview. Through the technique of written discourse analysis and the array built upon Bronfenbrenner's bioecological theory, we obtained three categories: fathers' needs/concerns, generated in their relationship with the world of work; needs/concerns that emerged from the relationship of care with the children; and fathers' concerns about the future of the children. Conclusions: we identified that the concern with the future of the children was pointed out by fathers of all age groups investigated. .

Objetivo: identificar las necesidades y preocupaciones prioritarias, manifestadas por los padres en el desempeño de su función, en tres etapas del ciclo de vida: adolescencia, edad productiva y edad madura. Metodología: estudio exploratorio con abordaje cualitativo, desarrollado con catorce padres residentes en un municipio en el extremo sur de Brasil. Los datos fueran colectados entre mayo y agosto de 2011, a través de entrevistas en profundidad. A través de la técnica de análisis textual y discursiva e de la matriz construida basada en la teoria bioecologica de Bronfenbrenner, fueran construidas tres categorías: Necesidades/ preocupaciones de lo padre, generado en suya relación con el mundo de lo trabajo; Necesidades/preocupaciones que emergen de la relación de cuidado con hijos e preocupaciones de los padres con lo futuro de los hijos. Conclusión: Se identifico que la preocupación con el futuro de los hijos fue apuntado por los padres de todas las edades averiguadas. .

Coenzyme A Ligases/isolation & purification , Phenylacetates/metabolism , Pseudomonas/enzymology , Amino Acids/analysis , Chromatography, Gel , Chromatography, High Pressure Liquid , Chromatography, Ion Exchange , Coenzyme A Ligases/biosynthesis , Coenzyme A Ligases/metabolism , Electrophoresis, Polyacrylamide Gel , Kinetics , Molecular Weight , Pseudomonas/growth & development , Substrate Specificity , Thermodynamics , Ultracentrifugation
Rev. latinoam. enferm ; 22(6): 902-910, 16/12/2014. tab
Article in English | LILACS, BDENF | ID: lil-732951


METHOD: one hundred (n=100) elderly outpatients with diabetic retinopathy taking antihypertensives and/or oral antidiabetics/insulin were interviewed. Adherence was evaluated by the adherence proportion and its association with the care taken in administrating medications and by the Morisky Scale. The National Eye Institute Visual Functioning Questionnaire (NEI VFQ-25) was used to evaluate HRQoL. RESULTS: most (58%) reported the use of 80% or more of the prescribed dose and care in utilizing the medication. The item "stopping the drug when experiencing an adverse event", from the Morisky Scale, explained 12.8% and 13.5% of the variability of adherence proportion to antihypertensives and oral antidiabetics/insulin, respectively. CONCLUSION: there was better HRQoL in the Color Vision, Driving and Social Functioning domains of the NEI VFQ-25. Individuals with lower scores on the NEI VFQ-25 and higher scores on the Morisky Scale presented greater chance to be nonadherent to the pharmacological treatment of diabetes and hypertension. .

OBJETIVO: investigar os fatores relacionados à adesão medicamentosa e sua relação com a qualidade de vida relacionada à saúde em idosos com retinopatia diabética. MÉTODO: foram entrevistados 100 idosos, em acompanhamento ambulatorial, em uso de anti-hipertensivos e/ou antidiabéticos orais/insulina. A adesão foi avaliada pela proporção de adesão e sua associação com os cuidados no uso dos medicamentos e pela Escala de Morisky. O National Eye Institute Visual Funcioning Questionnaire foi utilizado para avaliar a qualidade de vida relacionada à saúde. RESULTADOS: A maioria (58%) relatou o uso de 80% ou mais das doses prescritas e os cuidados na tomada dos medicamentos. O item "interromper o uso dos medicamentos por se sentir pior", da Escala de Morisky, explicou 12,8 e 13,5% da variabilidade da proporção de adesão aos anti-hipertensivos e aos antidiabéticos orais/insulina, respectivamente. CONCLUSÃO: observou-se melhor qualidade de vida relacionada à saúde nos domínios visão de cores, dirigir automóvel e apectos sociais do National Eye Institute Visual Funcioning Questionnaire. Indivíduos com menor pontuação na National Eye Institute Visual Funcioning Questionnaire e maiores escores na Escala de Morisky apresentaram maiores chances de serem não aderentes aos medicamentos do diabetes e da hipertensão arterial. .

OBJETIVO: investigar los factores relacionados a la adhesión a la medicación y su relación con la Calidad de Vida Relacionada a la Salud (CVRS) de ancianos con retinopatía diabética. MÉTODO: fueron entrevistados cien (n=100) pacientes ancianos de ambulatorio con retinopatía diabética que toman medicamentos antihipertensivos y/o antidiabéticos orales/insulina. La adhesión fue evaluada mediante la proporción de adhesión y su asociación con el cuidado tomado en la administración de medicamentos y mediante la Escala de Morisky. El National Eye Institute Visual Functioning Questionnaire (NEI VFQ-25) fue usado para evaluar la CVRS. RESULTADOS: la mayoría (58%) relató el uso de 80% o más de la dosis prescrita y cuidado con el uso de la medicación. El ítem "suspender la droga cuando vivencia un evento adverso", de la Escala de Morisky, explicó 12.8% y 13.5% de la variabilidad en la proporción de adhesión a los antihipertensivos y antidiabéticos orales/insulina, respectivamente. CONCUSIÓN: fue encontrada mejor CVRS en los dominios de Visión Cromática, Dirección y Funcionamiento Social del NEI VFQ-25. Individuos con puntuaciones menores en el NEI VFQ-25 y puntuaciones mayores en la Escala de Morisky revelaron mayor chance de no adhesión al tratamiento farmacológico de la diabetes y hipertensión. .

Animals , Cattle , Arsenites , DNA , DNA-Binding Proteins/physiology , Receptors, Glucocorticoid/metabolism , Sodium Compounds , Thymus Gland/metabolism , Arsenic/pharmacology , Chemical Phenomena , Chemistry , Chromatography, Gel , Cytosol/metabolism , Dextrans , Methyl Methanesulfonate/analogs & derivatives , Methyl Methanesulfonate/pharmacology , Molybdenum/pharmacology
Salud pública Méx ; 56(6): 654-659, nov.-dic. 2014. tab
Article in Spanish | LILACS | ID: lil-733345


La listeriosis es una enfermedad transmitida por alimentos (ETA) y ocasionada por Listeria monocytogenes. La importancia de ésta se debe a su impacto clínico, la alta tasa de mortalidad y el efecto económico derivado de los brotes asociados con el consumo de alimentos. En México, las fallas en los sistemas de vigilancia epidemiológicos son causa de información imprecisa sobre la incidencia de la listeriosis y sobre su caracterización como ETA. En este trabajo se presentan datos referentes a la presencia de la bacteria en alimentos, reportes de casos de la enfermedad y patologías relacionadas con infección por L. monocytogenes. La falta de datos exactos sobre la importancia de esta bacteria plantea la necesidad de concientizar a las instancias correspondientes para definir estrategias de búsqueda intencionada de L. monocytogenes en alimentos y de la recopilación de información clínica precisa que permita conocer la importancia clínica y epidemiológica de la listeriosis en México.

Listeriosis is caused by Listeria monocytogenes, an important food-borne disease due to its clinical forms, high mortality rate, and the economic impact in both clinical and food production industries. In Mexico, the lack of epidemiological surveillance systems leads to the need of accurate data on the incidence of listeriosis and its association with food-borne disease. In this paper, we present data about the presence of this bacterium in food, reports related to clinical cases of listeriosis, and information of diseases in which L. monocytogenes may be involved. However, in most of these cases the etiology was not established. Given this, there's a need to inform and warn the appropriate entities, to define strategies for the mandatory search of L. monocytogenes through the whole food production chain and clinical suspects, for the epidemiological importance and control of listeriosis in Mexico.

Animals , Cysteine Endopeptidases/isolation & purification , Egg Proteins/metabolism , Enzyme Precursors/isolation & purification , Antimalarials/pharmacology , Chromatography, Gel , Cysteine Endopeptidases/metabolism , Cysteine Proteinase Inhibitors/pharmacology , Electrophoresis, Polyacrylamide Gel , Enzyme Activation , Egg Yolk/chemistry , Enzyme Precursors/metabolism , Hydrogen-Ion Concentration , Leucine/analogs & derivatives , Leucine/metabolism , Molecular Weight , Orthoptera
Indian J Exp Biol ; 2014 Nov; 52(11):1036-1044
Article in English | IMSEAR | ID: sea-153784


The extracellular crude dextransucrase (0.67 U/mg) from P. pentosaceus CRAG3 (GenBank accession number JX679020) after PEG-1500 fractionation gave specific activity, 20.0 U/mg which by gel filtration resulted in 46.0 U/mg. The purified dextransucrase displayed molecular size of approximately, 224 kDa. The optimum assay conditions for dextransucrase activity were 5% sucrose in 20 mM sodium acetate buffer (pH 5.4) and 30 oC. The dextransucrase was stable up to 40 oC and at pH range of 5.4-7.0. The metal ions such as Co2+, Ca2+, Mg2+ and Zn2+ stimulated the dextransucrase activity by 56, 44, 14 and 12%, respectively. It was most stable at -20 oC with half-life of 307 days. Amongst various additives used, glycerol and Tween 80 provided significant stability to the enzyme with half-life 15.5 and 85.5 h, respectively as compared to control (6.9 h). The solidification of sucrose supplemented milk by purified dextransucrase due to dextran synthesis displayed its application as additive for improving the texture of dairy products.

Cations, Divalent/pharmacology , Chromatography, Gel , Drug Storage , Electrophoresis, Polyacrylamide Gel , Food Additives , Fungal Proteins/chemistry , Fungal Proteins/isolation & purification , Glucosyltransferases/chemistry , Glucosyltransferases/isolation & purification , Half-Life , Hydrogen-Ion Concentration , Molecular Weight , Pediococcus/enzymology , Protein Stability , Temperature
Rev. panam. salud pública ; 36(5): 306-313, nov. 2014. tab
Article in English | LILACS | ID: lil-733233


OBJECTIVE: To determine and describe the prevalence and patterns of three recommended practices for infant and young child feeding-exclusive breastfeeding (EB), continued breastfeeding (CB), and achievement of minimum dietary diversity-in four regions in Haiti, and to identify the attitudes and beliefs that inform these practices and any other factors that may facilitate or impede their implementation. METHODS: This study utilized a mixed-methods approach consisting of 1) a cross-sectional survey (n = 310) and 2) 12 focus group discussions among women ≥18 years old with children ≤ 2 years old. Multivariable logistic regression analyses were conducted to identify factors associated with 1) EB during the first six months of life, 2) CB for children ≥ 2 years old, and 3) receipt of a diverse variety of complementary foods. Qualitative data were recorded, transcribed verbatim, and analyzed for common themes. Data were collected in June and July 2013 in four departments in Haiti: Artibonite, Nippes, Ouest, and Sud-Est. RESULTS: Prevalence of EB, CB, and achievement of minimum dietary diversity was 57.0%, 11.9%, and 21.2% respectively. EB was statistically significantly associated with infant's age when controlling for annual household income, location of most recent birth, or receipt of CB counseling (odds ratio (OR) = 0.67 (95% CI: 0.47-0.97)). CB was not statistically significantly associated with rural place of residence, receipt of CB counseling, parity, or infant's age. Meeting minimum dietary diversity was not significantly associated with parity, receipt of postnatal care, rural place of residence, location of most recent birth, receipt of infant and young child feeding counseling, or level of schooling. Beliefs surrounding the relationship between the mother's health and her diet on the quality of breast milk may prohibit EB and CB. Qualitative data revealed that dietary diversity may be low because 1) mothers often struggle to introduce complementary foods and 2) those that are traditionally introduced are not varied and primarily consist of grains and starches. CONCLUSIONS: Prevalence of the three recommended infant and young child feeding practices examined in this study is suboptimal, particularly CB and achievement of minimum dietary diversity. Future communication and programming efforts should address the misunderstandings and concerns identified through the qualitative methods used in this research.

OBJETIVO: Determinar y describir la prevalencia y los modelos de tres prácticas recomendadas para la alimentación de los lactantes y los niños pequeños (la lactancia materna exclusiva [LME], la lactancia materna continuada [LMC] y el logro de una diversidad alimentaria mínima, en cuatro regiones de Haití, y determinar las actitudes y creencias en las que se basan estas prácticas y otros factores que puedan facilitar o impedir su implantación. MÉTODOS: Este estudio utilizó un diseño de método mixto que consistió en 1) una encuesta transversal (n = 310) y 2) 12 grupos de discusión formados por mujeres de ≥ 18 años de edad o mayores con niños de ≤ 2 años de edad o menores. Se llevaron a cabo análisis de regresión logística multivariable para determinar los factores asociados con 1) la LME durante los seis primeros meses de vida, 2) la LMC en niños de ≥ 2 años de edad o mayores, y 3) el aporte de una amplia variedad de alimentos complementarios. Se registraron, se transcribieron al pie de la letra y se analizaron los datos cualitativos referentes a temas comunes. Estos datos se recopilaron en junio y julio del 2013, en cuatro departamentos de Haití: Artibonite, Nippes, Oeste y Sudeste. RESULTADOS: Las prevalencias de la LME, la LMC y el logro de una diversidad alimentaria mínima fueron de 57,0, 11,9 y 21,2%, respectivamente. La LME se asoció de manera estadísticamente significativa con la edad del lactante si se controlaban las variables de ingresos familiares anuales, ubicación del parto más reciente, o provisión de orientación en materia de LMC (razón de posibilidades [OR] = 0,67 [IC de 95%:0.47-0.97]). La LMC no se asoció de una manera estadísticamente significativa con la residencia en un entorno rural, la provisión de orientación en materia de LMC, la paridad o la edad de lactante. El logro de una diversidad alimentaria mínima no se asoció significativamente con la paridad, la provisión de atención posnatal, la residencia en un entorno rural, la ubicación del parto más reciente, la provisión de orientación en materia de alimentación de los lactantes y los niños pequeños, o el nivel de escolarización. Las creencias con respecto a la relación entre la salud de la madre y su régimen alimentario con la calidad de la leche materna pueden limitar la LME y la LMC. Los datos cualitativos revelaron que la diversidad alimentaria puede ser escasa como consecuencia de que 1) las madres a menudo se esfuerzan por introducir los alimentos complementarios, y 2) los que se introducen tradicionalmente no son variados y consisten principalmente en cereales y féculas. CONCLUSIONES: Las prevalencias de las tres prácticas de alimentación de los lactantes y los niños pequeños recomendadas analizadas en este estudio son subóptimas, en particular las correspondientes a la LMC y al logro de una diversidad alimentaria mínima. Las futuras iniciativas de comunicación y programación deberían abordar los malentendidos y las inquietudes detectadas mediante los métodos cualitativos utilizados en esta investigación.

Escherichia coli/chemistry , Sigma Factor/isolation & purification , Chromatography, Gel , Chromatography, High Pressure Liquid , Cloning, Molecular , DNA Primers/genetics , Electrophoresis, Polyacrylamide Gel , Protein Conformation , Plasmids/genetics , Promoter Regions, Genetic/genetics , Sarcosine/analogs & derivatives , Sarcosine/pharmacology , Sigma Factor/genetics , Transcription, Genetic/genetics
Braz. j. microbiol ; 45(3): 1007-1015, July-Sept. 2014. ilus, graf, tab
Article in English | LILACS | ID: lil-727032


In the present study, a bacterium isolated from Marcha- a herbal cake used as traditional starter culture to ferment local wine in North East India, was evaluated for bacteriocin like inhibitory substance production and was tested against six food borne/spoilage causing pathogens viz. Listeria monocytogenes MTCC 839, Bacillus subtilis MTCC 121, Clostridium perfringens MTCC 450, Staphylococcus aureus, Lactobacillus plantarum and Leuconostoc mesenteroides MTCC 107 by using bit/disc method followed by well diffusion method. The bacterial isolate was identified as Brevibacillus borstelensis on the basis of phenotypic, biochemical and molecular characteristics using 16Sr RNA gene technique. Bacteriocin like inhibitory substance produced by Brevibacillus borstelensis AG1 was purified by gel exclusion chromatography. The molecular mass of the Brevibacillus borstelensis AG1 was found to be 12 kDa. Purified bacteriocin like inhibitory substance of Brevibacillus borstelensis was further characterized by studying the effect of temperature, pH, proteolytic enzyme and stability. Bacteriocin like inhibitory substance was found to be thermostable upto 100 °C, active at neutral pH, sensitive to trypsin, and partially stable till third week of storage thus showing a bright prospective to be used as a potential food biopreservative.

Bacteriocins/isolation & purification , Bacteriocins/pharmacology , Brevibacillus/isolation & purification , Brevibacillus/metabolism , Gram-Positive Bacteria/drug effects , Bacteriocins/chemistry , Chromatography, Gel , Cluster Analysis , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Food Microbiology , India , Microbial Sensitivity Tests , Molecular Sequence Data , Molecular Weight , Phylogeny , Protein Stability/radiation effects , /genetics , Sequence Analysis, DNA , Temperature
Arq. bras. endocrinol. metab ; 58(1): 9-22, 02/2014. tab, graf
Article in English | LILACS | ID: lil-705235


The definition of the etiology of hyperprolactinemia often represents a great challenge and an accurate diagnosis is paramount before treatment. Although prolactin levels > 200-250 ng/mL are highly suggestive of prolactinomas, they can occasionally be found in other conditions. Moreover, as much as 25% of patients with microprolactinomas may present prolactin levels < 100 ng/mL, which are found in most patients with pseudoprolactinomas, drug-induced hyperprolactinemia, or systemic diseases. On the other hand, some conditions may lead to falsely low PRL levels, particularly the so-called hook effect, that is an assay artifact caused by an extremely high level of PRL, and can be confirmed by repeating assay after a 1:100 serum sample dilution. The hook effect must be considered in all patients with large pituitary adenomas and PRL levels within the normal range or only modestly elevated (e.g., < 200 ng/mL). An overlooked hook effect may lead to incorrect diagnosis and unnecessary surgical intervention in patients with prolactinomas. Another important challenge is macroprolactinemia, a common finding that needs to be identified, as it usually requires no treatment. Although most macroprolactinemic patients are asymptomatic, many of them may present galactorrhea or menstrual disorders, as well as neuroradiological abnormalities, due to the concomitance of other diseases. Finally, physicians should be aware that pituitary incidentalomas are found in at least 10% of adult population. Arq Bras Endocrinol Metab. 2014;58(1):9-22.

A definição da etiologia da hiperprolactinemia muitas vezes representa um grande desafio e um diagnóstico preciso é fundamental antes do tratamento. Embora níveis de prolactina > 200-250 ng/mL sejam altamente sugestivos de prolactinomas, ocasionalmente podem ser encontrados em outras condições. Além disso, até 25% dos pacientes com microprolactinomas podem apresentar-se com níveis de prolactina < 100 ng/mL, os quais são evidenciados na maioria dos pacientes com pseudoprolactinomas, hiperprolactinemia induzida por drogas ou doenças sistêmicas. Por outro lado, deve-se atentar às condições que podem levar a valores de prolactina falsamente baixos, particularmente o chamado efeito gancho. Este último é um artefato causado por um nível extremamente elevado de PRL e que pode ser confirmado pela repetição do exame após diluição do soro a 1:100. O efeito gancho deve ser considerado em todo paciente com grandes adenomas hipofisários e níveis de prolactina dentro da faixa normal ou apenas moderadamente elevados (p. ex., < 200 ng/mL). Um efeito gancho não detectado pode levar a diagnóstico incorreto e intervenção cirúrgica desnecessária em pacientes com prolactinomas. Outro desafio importante é a macroprolactinemia, um achado comum que precisa ser identificado visto que geralmente não requer tratamento. Ainda que a maioria dos pacientes seja assintomática devido à concomitância de outras doenças, muitos podem apresentar galactorreia ou distúrbios menstruais, bem como anormalidades neurorradiológicas. Finalmente, os médicos devem estar cientes de que incidentalomas hipofisários são encontrados em pelo menos 10% da população adulta. Arq Bras Endocrinol Metab. 2014;58(1):9-22.

Female , Humans , Male , Hyperprolactinemia/diagnosis , Hyperprolactinemia/etiology , Prolactin/blood , Prolactinoma/complications , Chemical Precipitation , Chromatography, Gel , Galactorrhea/etiology , Magnetic Resonance Imaging , Medical History Taking , Physical Examination , Prolactin/classification