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1.
Am J Primatol ; 86(7): e23635, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38738522

RESUMEN

The golden lion tamarin (GLT) is an Endangered primate endemic to Brazil's lowland Atlantic Forest. After centuries of deforestation and capture for the pet trade, only a few hundred individuals survived, all in isolated forest fragments 85 km from Rio de Janeiro city. Intensive conservation actions, including reintroduction of zoo-born tamarins, increased numbers to about 3700 in 2014. The most severe yellow fever epidemic/epizootic in Brazil in 80 years reduced two of the largest GLT populations by over 90%. Herein we report the results of a 2023 survey of GLTs designed to examine the dynamics of population recovery following yellow fever. Results indicate that populations hard hit by yellow fever are recovering due in part to immigration from adjacent forest fragments. No local extirpations were observed. About 4800 GLTs live in the survey area. This represents a 31% increase since the baseline survey completed in 2014. Two factors explain most of the increase: four large areas that had no GLTs or very low-density populations in 2014 are now at moderate density (three areas) or low density (one area), explaining 71% of overall increase since 2014. Increase in forest area within our survey area may explain up to 16% of the increase in GLT numbers since 2014. Results of computer simulations suggest that strengthening forest connectivity will facilitate metapopulation resilience in the face of mortality factors such as yellow fever.


Asunto(s)
Leontopithecus , Dinámica Poblacional , Fiebre Amarilla , Animales , Fiebre Amarilla/epidemiología , Brasil/epidemiología , Enfermedades de los Monos/epidemiología , Especies en Peligro de Extinción , Conservación de los Recursos Naturales , Femenino , Masculino
2.
Neurosurg Focus Video ; 9(2): V3, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37854644

RESUMEN

A 58-year-old male was admitted to the authors' department due to cervicothoracic pain and disequilibrium. Physical examination evidenced sensory and motor deficits in the lower limbs. MRI evidenced an expansive intramedullary lesion compatible with ependymoma. The nuances of this surgical access and the management of intradural tumors are discussed.

3.
Bioprocess Biosyst Eng ; 46(5): 681-692, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36806976

RESUMEN

Bioreactors can perform biochemical conversions mediated by biocatalysts, such as enzymes, animal cells, plants, and microorganisms. Among several existing models, airlift bioreactors are devices with the low shear environment and good mass transfer with low energy consumption, employed in several biochemical processes. The fluid flow is enabled through air injection by the sparger located at the bioreactor base. Despite its simple geometry compared with the conventional bioreactors, airlift performance can be optimized via geometrical modifications. Therefore, the objective of this work was to evaluate the effects of the addition of helical flow promoters, positioned in the riser and/or downcomer regions of an airlift of concentric tubes measuring the volumetric oxygen coefficient (kLa) and gas holdup. The results obtained by varying the gas flow rate from 1.0 to 4.0 vvm allowed the system evaluation of oxygen transfer and gas holdup. The inclusion of helical flow promoters increased the kLa, reaching up to 23% in oxygen transfer compared to tests without helicoids and up to 14% increase in the gas holdup. The inclusion of helical flow promotors was beneficial for all gas flow rates. Thus, including these flow promoters is an effective strategy to increase the oxygen transfer rate for bioprocess optimization.


Asunto(s)
Reactores Biológicos , Oxígeno , Oxígeno/química
4.
An Acad Bras Cienc ; 94(4): e20210262, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35946750

RESUMEN

Cattle ranching is the primary land-use of deforested areas in the Brazilian Amazon. Deforestation precedes pasture establishment, implying tremendous amounts of greenhouse gas emissions caused by carbon stock losses. Despite several studies addressing carbon storage in forests, there is a lack of data regarding cultivated pastures. Hence, the estimation of greenhouse gas emissions associated with land-use change becomes uncertain. In this study, we assessed the carbon stock of cultivated pastures located in Rondônia, southwestern Brazilian Amazon. A total of 50 squared plots of 1 m² were randomly allocated in cattle ranching farms covered by Oxisols (Dystrophic Yellow and Dystrophic Red-Yellow Latosols). Carbon fraction ranged from 0.36 for belowground biomass to 0.45 gC.g-1 d.m. for aboveground biomass. The average total carbon stock was 5.17 MgC.ha-1, with non-significant differences when stratifying data by soil types. Considering data from the III Brazilian Inventory of Anthropogenic Emissions and Removals of Greenhouse Gases, our results suggested that land-use change from primary forests to cultivated pastures resulted in a loss of 192.54 MgC.ha-1, which corresponds to a net emission of 705.98 MgCO2eq.ha-1 to the atmosphere. This study provides valuable information to improve the Brazilian Inventory of Anthropogenic Emissions and Removals of Greenhouse Gases.


Asunto(s)
Carbono , Gases de Efecto Invernadero , Animales , Brasil , Carbono/análisis , Bovinos , Conservación de los Recursos Naturales , Bosques
5.
Braz J Microbiol ; 53(3): 1263-1269, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35426068

RESUMEN

Immunological assays to detect SARS-CoV-2 Spike Receptor Binding Domain (RBD) antigen seroconversion in humans are important tools to monitor the levels of protecting antibodies in the population in response to infection and/or immunization. Here we describe a simple, low cost, and high throughput Ni2+ magnetic bead immunoassay to detect human IgG reactive to Spike S1 RBD Receptor Binding Domain produced in Escherichia coli. A 6xHis-tagged Spike S1 RBD was expressed in E. coli and purified by affinity chromatography. The protein was mobilized on the surface of Ni2+ magnetic beads and used to investigate the presence of reactive IgG in the serum obtained from pre-pandemic and COVID-19 confirmed cases. The method was validated with a cohort of 290 samples and an area under the receiver operating characteristic curve of 0.94 was obtained. The method was operated with > 82% sensitivity at 98% specificity and was also able to track human IgG raised in response to vaccination with Comirnaty at > 85% sensitivity. The IgG signal obtained with the described method was well-correlated with the signal obtained when pre fusion Spike produced in HEK cell lines was used as antigen. This novel low-cost and high throughput immunoassay may act as an important tool to investigate protecting IgG antibodies against SARS-CoV-2 in the human population.


Asunto(s)
COVID-19 , SARS-CoV-2 , Anticuerpos Antivirales , Escherichia coli/genética , Humanos , Inmunoensayo/métodos , Inmunoglobulina G , Fenómenos Magnéticos , SARS-CoV-2/genética , Glicoproteína de la Espiga del Coronavirus/genética
6.
Anal Biochem ; 631: 114360, 2021 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-34481802

RESUMEN

To monitor the levels of protecting antibodies raised in the population in response to infection and/or to immunization with SARS-CoV-2, we need a technique that allows high throughput and low-cost quantitative analysis of human IgG antibodies reactive against viral antigens. Here we describe an ultra-fast, high throughput and inexpensive assay to detect SARS-CoV-2 seroconversion in humans. The assay is based on Ni2+ magnetic particles coated with His tagged SARS-CoV-2 antigens. A simple and inexpensive 96 well plate magnetic extraction/homogenization process is described which allows the simultaneous analysis of 96 samples and delivers results in 7 min with high accuracy.


Asunto(s)
Anticuerpos Antivirales/sangre , Prueba Serológica para COVID-19/métodos , COVID-19/diagnóstico , Inmunoglobulina G/sangre , SARS-CoV-2/aislamiento & purificación , Anticuerpos Antivirales/inmunología , Antígenos Virales/sangre , Antígenos Virales/inmunología , COVID-19/sangre , COVID-19/inmunología , Prueba Serológica para COVID-19/economía , Ensayo de Inmunoadsorción Enzimática/economía , Ensayo de Inmunoadsorción Enzimática/métodos , Humanos , Inmunoglobulina G/inmunología , Imanes/química , Níquel/química , SARS-CoV-2/inmunología , Sensibilidad y Especificidad , Seroconversión , Factores de Tiempo
7.
Braz J Microbiol ; 52(4): 2069-2073, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34342836

RESUMEN

Serological assays are important tools to identify previous exposure to SARS-CoV-2, helping to track COVID-19 cases and determine the level of humoral response to SARS-CoV-2 infections and/or immunization to future vaccines. Here, the SARS-CoV-2 nucleocapsid protein was expressed in Escherichia coli and purified to homogeneity and high yield using a single chromatography step. The purified SARS-CoV-2 nucleocapsid protein was used to develop an indirect enzyme-linked immunosorbent assay for the identification of human SARS-CoV-2 seroconverts. The assay sensitivity and specificity were determined analyzing sera from 140 RT-qPCR-confirmed COVID-19 cases and 210 pre-pandemic controls. The assay operated with 90% sensitivity and 98% specificity; identical accuracies were obtained in head-to-head comparison with a commercial ELISA kit. Antigen-coated plates were stable for up to 3 months at 4 °C. The ELISA method described is ready for mass production and will be an additional tool to track COVID-19 cases.


Asunto(s)
COVID-19 , Proteínas de la Nucleocápside de Coronavirus/inmunología , Ensayo de Inmunoadsorción Enzimática , Seroconversión , Anticuerpos Antivirales/sangre , COVID-19/diagnóstico , COVID-19/inmunología , Humanos , Inmunidad Humoral , Proteínas de la Nucleocápside/genética , Fosfoproteínas/inmunología , Sensibilidad y Especificidad
8.
Mol Cell Endocrinol ; 535: 111393, 2021 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-34245846

RESUMEN

Reproductive cancers in both genders represent serious health problems, whose incidence has significantly risen over the past decades. Although considerable differences among reproductive cancers exist, we aimed to identify similar signaling pathways and key molecular oncomarkers shared among six human reproductive cancers that can advance the current knowledge of cancer biology to propose new strategies for more effective therapies. Using a computational analysis approach, here we uncover aberrant miRNAs-mRNAs networks shared in six reproductive tumor types, and identify common molecular mechanisms strictly associated with cancer promotion and aggressiveness. Based on the fact that estrogenic and androgenic signaling pathways were most active in prostate and breast cancers, we further demonstrated that both androgen and estrogen deprivation therapy are capable of regulating the expression of the same key molecular sensors associated with endoplasmic reticulum dysfunction and cell cycle in these cancers. Overall, our data reveal a potential mechanistic framework of cellular processes that are shared among reproductive cancers, and particularly, highlight the importance of hormonal deprivation in breast and prostate cancers and potentially new biomarkers of response to these therapeutic approaches.


Asunto(s)
Neoplasias de la Mama/genética , Biología Computacional/métodos , Neoplasias Endometriales/genética , Redes Reguladoras de Genes , MicroARNs/genética , Neoplasias de Células Germinales y Embrionarias/genética , Neoplasias Ováricas/genética , Neoplasias de la Próstata/genética , Neoplasias Testiculares/genética , Neoplasias Uterinas/genética , Antagonistas de Andrógenos/farmacología , Antagonistas de Andrógenos/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Bases de Datos Genéticas , Neoplasias Endometriales/tratamiento farmacológico , Antagonistas de Estrógenos/farmacología , Antagonistas de Estrógenos/uso terapéutico , Femenino , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Redes Reguladoras de Genes/efectos de los fármacos , Humanos , Masculino , Neoplasias de Células Germinales y Embrionarias/tratamiento farmacológico , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias de la Próstata/tratamiento farmacológico , Análisis de Supervivencia , Neoplasias Testiculares/tratamiento farmacológico , Neoplasias Uterinas/tratamiento farmacológico
9.
Bioprocess Biosyst Eng ; 44(8): 1721-1732, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33821325

RESUMEN

The production of biocompounds through the cultivation of filamentous microorganisms is mainly affected by Oxygen Transfer Rate (OTR) and shear rate ([Formula: see text]) conditions. Despite efforts have been made to evaluate the effect of operating variables (impeller speed, N; and airflow rate, ϕair) on clavulanic acid production, no analysis regarding the effect of OTR and [Formula: see text] was made. Then, the aim of this study was to evaluate the dissociated effect of physical phenomena such as oxygen transfer and shear rate in the production of clavulanic acid from Streptomyces clavuligerus using a stirred tank bioreactor. Streptomyces clavuligerus cultivations were performed at five different OTR and [Formula: see text] conditions by manipulating the operating conditions (N, ϕair, and gas inlet composition). Cultivations performed at equal impeller speed (600 rpm, similar [Formula: see text]) using oxygen enrichment, showed that CA productivity (ProdCA) was positively affected by OTR increase. Subsequently, the different shear conditions (achieved by varying the impeller speed) lead to an increase in CA production levels. Despite both OTR and shear rate positively enhanced CA productivity, [Formula: see text] exhibited the highest impact: an increase of 145% in OTRinitial enhanced the clavulanic acid productivity of about 29%, while an increment in the shear rate of 134% raised the ProdCA in 53%.


Asunto(s)
Ácido Clavulánico/química , Microbiología Industrial/métodos , Oxígeno/química , Streptomyces/metabolismo , Reactores Biológicos , Biotecnología/métodos , Medios de Cultivo , Diseño de Equipo , Resistencia al Corte , Factores de Tiempo
10.
Animals (Basel) ; 11(2)2021 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-33494489

RESUMEN

The whole corn germ (WCG), due to its desirable nutritional characteristics, has been studied as feed for ruminants. This study aimed to evaluate the effects of WCG inclusion as a linoleic acid source in diets for feedlot lambs on carcass characteristics, physicochemical composition, sensory attributes, and fatty acid profile of the meat. Forty non-castrated, crossbreed Dorper x Santa Inês lambs were distributed in a completely randomized design to evaluate the inclusion levels (0, 30, 60, 90, and 120 g/kg dry matter (DM)) of whole corn germ (WCG) in the diet. The dietary inclusion of WCG did not influence (p > 0.05) the weight gain and carcass characteristics, with the exception of the subcutaneous fat thickness (p < 0.01), which was higher in animals fed diets with higher levels of WCG. Lightness (L *; p = 0.04), yellowness (b *; p < 0.01), shear force (p = 0.04), linoleic fatty acid concentrations (p = 0.03), and total polyunsaturated fatty acids (p = 0.04) had a quadratic increase due to WCG inclusion in the diets. The use of up to 120 g/kg DM of WCG in lamb diets does not affect the carcass characteristics, physicochemical composition, and sensory attributes of the meat. Despite this, the best polyunsaturated fatty acid profile in lambs' meat is obtained using 76.7 g/kg DM of WCG.

11.
ACS Sens ; 6(3): 703-708, 2021 03 26.
Artículo en Inglés | MEDLINE | ID: mdl-33496577

RESUMEN

Immunological methods to detect SARS-CoV-2 seroconversion in humans are important to track COVID-19 cases and the humoral response to SARS-CoV-2 infections and immunization to future vaccines. The aim of this work was to develop a simple chromogenic magnetic bead-based immunoassay which allows rapid, inexpensive, and quantitative detection of human antibodies against SARS-CoV-2 in serum, plasma, or blood. Recombinant 6xHis-tagged SARS-CoV-2 Nucleocapsid protein was mobilized on the surface of Ni2+ magnetic beads and challenged with serum or blood samples obtained from controls or COVID-19 cases. The beads were washed, incubated with anti-human IgG-HPR conjugate, and immersed into a solution containing a chromogenic HPR substrate. Bead transfer and homogenization between solutions was aided by a simple low-cost device. The method was validated by two independent laboratories, and the performance to detect SARS-CoV-2 seroconversion in humans was in the same range as obtained using the gold standard immunoassays ELISA and Luminex, though requiring only a fraction of consumables, instrumentation, time to deliver results, and volume of sample. Furthermore, the results obtained with the method described can be visually interpreted without compromising accuracy as demonstrated by validation at a point-of-care unit. The magnetic bead immunoassay throughput can be customized on demand and is readily adapted to be used with any other 6xHis tagged protein or peptide as antigen to track other diseases.


Asunto(s)
Anticuerpos Antivirales/sangre , Prueba Serológica para COVID-19 , COVID-19/diagnóstico , Ensayo de Inmunoadsorción Enzimática/métodos , SARS-CoV-2/inmunología , COVID-19/sangre , COVID-19/inmunología , Humanos , Inmunoglobulina G/inmunología , Fenómenos Magnéticos
12.
Food Chem ; 344: 128603, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33234437

RESUMEN

Enzymatic lipophilization is an important process to extend the use of anthocyanins in lipidic media. In this work delphinidin 3-O-sambubioside (Dp3sam) isolated from Hibiscus sabdariffa L. flower was esterified with octanoic acid using Candida antarctica lipase B. The physical-chemical properties of the new lipophilic pigment were studied by UV-vis spectroscopy. Dp3sam with chloride, acetate and formate as counter ions were employed to study the lipophilization reaction. The hydrolysis of the reagent was avoided with a formate counter ion and the expected product was achieved with a noteworthy change of solubility. 1D and 2D NMR characterization of Dp3sam-C8 confirmed that the lipophilization took place at the primary alcohol of the glucoside moiety. Overall, the Dp3sam-C8 ester presents a stabilization of the quinoidal base (blue color) at neutral or moderate alkaline pH, which foresees a potential use of this pigment as a broad kind of industries on lipo-soluble formulations.


Asunto(s)
Antocianinas/análisis , Ácidos Grasos/metabolismo , Proteínas Fúngicas/metabolismo , Hibiscus/química , Lipasa/metabolismo , Acilación , Antocianinas/aislamiento & purificación , Antocianinas/metabolismo , Biocatálisis , Cromatografía Líquida de Alta Presión , Color , Disacáridos/química , Hibiscus/metabolismo , Concentración de Iones de Hidrógeno , Espectrometría de Masas , Extractos Vegetales/química , Extracción en Fase Sólida
13.
Enzyme Microb Technol ; 139: 109587, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32732036

RESUMEN

The hydrodynamic environment in bioreactors affects the oxygen transfer rate and the shear conditions during microbial cultivations. Therefore, assessment of the effect of the hydrodynamic environment on cellular morphology can contribute to favoring the production of metabolites of interest. The aim of this work was to use image analysis in order to quantify the fragmentation of Aspergillus niger pellets in a conventional bioreactor operated using different impeller speeds, air flow rates, and impeller configurations including Rushton turbines and Elephant Ear impellers, with evaluation of the influence of the hydrodynamic environment on the production of cellulolytic enzymes. An empirical kinetic model was proposed to describe the dynamics of pellet fragmentation and quantify the shear conditions. The results showed that the agitation speed affected the dynamics of pellet fragmentation in two ways, by accelerating the damage process and by increasing the magnitude of the fragmentation. Both endoglucanase and ß-glucosidase production exhibited a linear relationship with the pellet fragmentation percentage, which was directly related to the shear conditions. Interestingly, ß-glucosidase production was favored under high shear conditions, while the highest endoglucanase production occurred under low shear conditions. These findings may be useful for defining suitable systems and operating conditions for the production of metabolites including enzymes in bioreactors, as well as defining conditions that favour a specific pre-determined enzyme cocktail.


Asunto(s)
Aspergillus niger/enzimología , Reactores Biológicos , Celulasa/biosíntesis , beta-Glucosidasa/biosíntesis , Fermentación , Hidrodinámica , Cinética
14.
Bioprocess Biosyst Eng ; 42(6): 995-1008, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30848359

RESUMEN

The shear rate is an important bioreactor parameter that needs to be evaluated due to its impact on microorganism morphology and viability, and consequently on bioproduct formation. Airlift bioreactors, classified as low-shear devices, are used as an alternative to conventional stirred-tank reactors. Considerable efforts have been made to characterize the shear environments in airlift bioreactors, using the average shear rate ([Formula: see text]) as a key parameter. However, there is no agreement among the values obtained in different studies, which can differ even in orders of magnitude. The methodologies used to obtain [Formula: see text] in the different studies could be the reason for the lack of agreement among them. In this work, [Formula: see text] in a concentric tube airlift bioreactor was evaluated using computational fluid dynamics (CFD), as well as based on universal velocity profiles for liquid flows in smooth pipes and annuli. Good agreement was obtained between the CFD-based average shear rates and the values obtained from universal velocity profiles, indicating that CFD simulation is a valuable tool for [Formula: see text] prediction.


Asunto(s)
Reactores Biológicos , Hidrodinámica , Modelos Químicos , Resistencia al Corte
15.
Anticancer Agents Med Chem ; 18(15): 2070-2077, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30147015

RESUMEN

INTRODUCTION: The understanding of cancer has evolved into a complex disease, which has heterogeneous characteristics between different patients, and more than that, a broad range of genetically distinct cells in the same tumor. Chronic and non-transmissible diseases such as cancer have become even more important worldwide and advances in their characterization and properties are running out. In a suitable setting, early diagnosis of cancer and proper treatment are essential to overcome the barriers of tumor healing and quality assurance of the patient's life. The studies included in the analysis were independently retrieved by the authors. The text words included "Non-Small Cell Lung Cancer," "NSCLC," "biomarkers in NSCLC" and "gene in NSCLC"." We were used to perform a systematic literature search in the PubMed and Web of Science databases. There was limit on the start date for published articles (2001), and the search ended in December 2017. For a more comprehensive analysis, articles were only in English. Non-small Cell Lung Cancer (NSCLC) Microenvironment: This review focuses on lung cancer, especially NSCLC, one of the most worldwide common cancer types, showing the importance of tumor microenvironment in this disease. NSCLC Biomarkers: This review shows a molecular aspect of NSCLC biomarkers used in clinical approaches, such as EGFR, KRAS, MET, indicating mutations that are crucial for cancer progression and related to treatment properties. We also describe 11 drugs commonly used in cancer treatment that are correlated with the patient genetic profile. CONCLUSION: This review highlights the importance of molecular diagnosis of mutations in lung cancer, driving to individualized therapy with the intent of getting a better response to treatment and improving patients' quality of life.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/terapia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/terapia , Medicina de Precisión , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico , Humanos , Neoplasias Pulmonares/diagnóstico , Microambiente Tumoral
16.
Food Funct ; 9(3): 1726-1735, 2018 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-29493669

RESUMEN

The lack of digestibility of certain gluten proteins is essential in the development of celiac disease (CD). Gluten proteins are remarkably resistant to luminal and brush-border proteolysis owing to their high proline and glutamine content. Consequently, large fragments remain intact after digestion exerting toxic effects. Intestinal brush-border membrane vesicles (BBMV) have been described as having strong proteolytic activity mainly through prolyl endopeptidase enzymes. The purpose of this work was to monitor the gastrointestinal digestion of specific CD epitopes by means of an in vitro gastrointestinal digestion model that included incubation with brush-border membrane enzymes. Gluten hydrolysates were characterized by mass spectrometry and the immunologic peptides were tracked by searching the main T-cell stimulating epitopes which have been widely described. The immunologic potential of gluten hydrolysates was further analysed by enzyme-linked immunosorbent assay (ELISA). The results showed that the composition of gluten hydrolysates depended on the digestion time and protein structural characteristics. On the other hand, the main T-cell stimulating epitopes formed during hydrolysis depend on the precursor protein. Glutenin oligopeptides were degraded faster whereas gliadin, mainly α-gliadin oligopeptides, remained intact for a long time. MS-based analysis showed that the formation of the epitopes from γ-gliadin and ω-gliadin or glutenin was favoured but they were generally degraded during the gastrointestinal treatment. However, the peptides containing the epitope PFPQPQLPY (α-gliadin) remained intact even after 180 min of digestion time. Overall, from all the epitopes tracked, PFPQPQLPY was the most resistant to in vitro BBMV digestion.


Asunto(s)
Glútenes/química , Péptidos/química , Triticum/química , Enfermedad Celíaca/metabolismo , Digestión , Epítopos/química , Epítopos/metabolismo , Glútenes/metabolismo , Humanos , Mucosa Intestinal/metabolismo , Espectrometría de Masas , Péptidos/metabolismo , Proteolisis
17.
Food Funct ; 8(8): 2712-2721, 2017 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-28703824

RESUMEN

Immunogenic gluten peptides trigger Celiac Disease (CD), an adaptive immune response in genetically predisposed individuals. Given the structural similarity between all gluten proteins their individual CD influence is not clear. Hence, the extraction, separation and characterization of wheat gluten proteins have become relevant to measure their individual potential immunoreactivity. Wheat proteins were extracted from commercial wheat flour and further isolated by preparative HPLC. The resulting richest gliadin sub-fractions were characterized by nano-LC-MS/MS following a shotgun proteomic approach in order to identify the prolamins in the original commercial wheat flour. It was found that the gliadin extract was additionally composed of glutenins and avenin-like proteins. Accurate prolamin identification has emerged as a need to delve deep into the influence of each fraction on the onset of celiac disease. After protein characterization, the immunoreactivity towards the main epitope related to CD was verified by ELISA and western blotting for several different gluten fractions.


Asunto(s)
Enfermedad Celíaca/etiología , Harina/análisis , Prolaminas/química , Triticum/química , Cromatografía Líquida de Alta Presión , Ensayo de Inmunoadsorción Enzimática , Harina/efectos adversos , Humanos , Prolaminas/efectos adversos , Prolaminas/inmunología , Espectrometría de Masas en Tándem , Triticum/efectos adversos , Triticum/inmunología
18.
Food Funct ; 8(5): 2030-2037, 2017 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-28492692

RESUMEN

This study was designed to evaluate the pharmacokinetics of Port and table red wine anthocyanins in healthy men. Volunteers were recruited to drink 250 mL of a table red wine (221 mg of anthocyanins) and 150 mL of young Port red wine (49 mg of anthocyanins). Venous blood was collected from participants at 0, 15, 30, 60 and 120 min after wine ingestion. Urine samples were collected at baseline and at 120 min. Anthocyanins and anthocyanin metabolites in plasma and urine samples were quantified by HPLC-DAD and tentatively identified by LC-MS. Red wine anthocyanins were detected in their intact forms in both plasma and urine samples, but the glucuronylated metabolites of peonidin and malvidin (PnGlucr and MvGlucr) were the two main derivatives detected after both red wine consumptions. For the first time, and supported by the synthesis of Mv3Glucr, the main pathway followed by Mv3glc after absorption was described and involves anthocyanidin conjugation with glucuronic acid after glucose removal. Despite the lower total content of anthocyanins ingested when volunteers drank Port wine, no differences were observed in the plasma Cmax of MvGlucr and PnGlucr after table and Port red wine consumption. The relative bioavailability of anthocyanins in Port wine was 96.58 ± 5.74%, compared to the anthocyanins present in red wine. In conclusion, both Port and table red wines are good sources of bioavailable anthocyanins.


Asunto(s)
Antocianinas/sangre , Antocianinas/química , Vino/análisis , Adulto , Cromatografía Líquida de Alta Presión , Estudios Cruzados , Humanos , Masculino , Adulto Joven
19.
BMC Bioinformatics ; 16: 247, 2015 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-26250142

RESUMEN

BACKGROUND: The traditional method used to estimate tree biomass is allometry. In this method, models are tested and equations fitted by regression usually applying ordinary least squares, though other analogous methods are also used for this purpose. Due to the nature of tree biomass data, the assumptions of regression are not always accomplished, bringing uncertainties to the inferences. This article demonstrates that the Data Mining (DM) technique can be used as an alternative to traditional regression approach to estimate tree biomass in the Atlantic Forest, providing better results than allometry, and demonstrating simplicity, versatility and flexibility to apply to a wide range of conditions. RESULTS: Various DM approaches were examined regarding distance, number of neighbors and weighting, by using 180 trees coming from environmental restoration plantations in the Atlantic Forest biome. The best results were attained using the Chebishev distance, 1/d weighting and 5 neighbors. Increasing number of neighbors did not improve estimates. We also analyze the effect of the size of data set and number of variables in the results. The complete data set and the maximum number of predicting variables provided the best fitting. We compare DM to Schumacher-Hall model and the results showed a gain of up to 16.5% in reduction of the standard error of estimate. CONCLUSION: It was concluded that Data Mining can provide accurate estimates of tree biomass and can be successfully used for this purpose in environmental restoration plantations in the Atlantic Forest. This technique provides lower standard error of estimate than the Schumacher-Hall model and has the advantage of not requiring some statistical assumptions as do the regression models. Flexibility, versatility and simplicity are attributes of DM that corroborates its great potential for similar applications.


Asunto(s)
Biomasa , Minería de Datos/métodos , Monitoreo del Ambiente/métodos , Modelos Teóricos , Árboles/fisiología , Bosques , Dinámica Poblacional , Clima Tropical , Incertidumbre
20.
PLoS One ; 10(6): e0130164, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26107169

RESUMEN

The objective of this study was to evaluate the effects of different maturation systems on oocyte resistance after vitrification and on the phospholipid profile of the oocyte plasma membrane (PM). Four different maturation systems were tested: 1) in vitro maturation using immature oocytes aspirated from slaughterhouse ovaries (CONT; n = 136); 2) in vitro maturation using immature oocytes obtained by ovum pick-up (OPU) from unstimulated heifers (IMA; n = 433); 3) in vitro maturation using immature oocytes obtained by OPU from stimulated heifers (FSH; n = 444); and 4) in vivo maturation using oocytes obtained from heifers stimulated 24 hours prior by an injection of GnRH (MII; n = 658). A sample of matured oocytes from each fresh group was analyzed by matrix associated laser desorption-ionization (MALDI-TOF) to determine their PM composition. Then, half of the matured oocytes from each group were vitrified/warmed (CONT VIT, IMA VIT, FSH VIT and MII VIT), while the other half were used as fresh controls. Afterwards, the eight groups underwent IVF and IVC, and blastocyst development was assessed at D2, D7 and D8. A chi-square test was used to compare embryo development between the groups. Corresponding phospholipid ion intensity was expressed in arbitrary units, and following principal components analyses (PCA) the data were distributed on a 3D graph. Oocytes obtained from superstimulated animals showed a greater rate of developmental (P<0.05) at D7 (MII = 62.4±17.5% and FSH = 58.8±16.1%) compared to those obtained from unstimulated animals (CONT = 37.9±8.5% and IMA = 50.6±14.4%). However, the maturation system did not affect the resistance of oocytes to vitrification because the blastocyst rate at D7 was similar (P>0.05) for all groups (CONT VIT = 2.8±3.5%, IMA VIT = 2.9±4.0%, FSH VIT = 4.3±7.2% and MII VIT = 3.6±7.2%). MALDI-TOF revealed that oocytes from all maturation groups had similar phospholipid contents, except for 760.6 ([PC (34:1) + H]+), which was more highly expressed in MII compared to FSH (P<0.05). The results suggest that although maturation systems improve embryonic development, they do not change the PM composition nor the resistance of bovine oocytes to vitrification.


Asunto(s)
Membrana Celular/metabolismo , Calor , Oocitos/citología , Fosfolípidos/metabolismo , Animales , Bovinos , Femenino , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
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