126 research outputs found
Miniaturization of aqueous two-phase extraction for biological applications
Aqueous two-phase extraction (ATPE) is a biocompatible liquid-liquid (L-L) separation technique that has been under research for several decades towards the purification of biomolecules, ranging from small metabolites to large animal cells. More recently, with the emergence of rapid-prototyping techniques for fabrication of microfluidic structures with intricate designs, ATPE gained an expanded range of applications utilizing physical phenomena occurring exclusively at the microscale.
Studies of ATPSs at nanoliter-scale are further extending the range of applications of these systems by taking advantage of rapid diffusion times, increased degree of control of individual liquid streams and droplets, continuous flow and the integration of multi-dimensional separation modes. Several examples of microfluidic ATPS platforms are described.
The partition of molecules between two co-flowing liquid streams confined within a microchannel was successfully demonstrated by the on-line extraction of a fluorescein isothiocyanate (FITC) labeled immunoglobulin G (IgG) from a salt rich flow to a PEG rich flow. IgG diffusion to the PEG-rich phase was complete after 16 cm of channel using flow rates of 1 and 0.2 μL/min for the salt and PEGrich phases respectively. Besides proteins, ATPS have also been used to separate other more complex biomolecules in microfluidics such as virus-like particles.
The potential of miniaturization as a high-throughput screening tool has also been explored. The developed setup allowed the screening of a wide range of concentrations inside the microchannel by varying the flow rates of the solutions while using sub-mL volumes for each ATPS-forming system.
As a novel demonstration of the integrative potential of ATPE as a microfluidic sample preparation module, a microfluidic device comprising two modules was developed and used to perform a complex matrix clean-up in-line with an immunoassay.
References:
Silva, D. F., Azevedo, A. M., Fernandes, P., Chu, V. et al., Design of a microfluidic platform for monoclonal antibody extraction using an aqueous two-phase system. J. Chromatogr. A 2012, 1249, 1–7.
Jacinto, M. J., Soares, R. R. G., Azevedo, A. M., Chu, V. et al., Optimization and miniaturization of aqueous two phase systems for the purification of recombinant human immunodeficiency virus-like particles from a CHO cell supernatant. Sep. Purif. Technol. 2015, 154, 27–35.
Silva, D. F. C., Azevedo, A. M., Fernandes, P., Chu, V. et al., Determination of aqueous two phase system binodal curves using a microfluidic device. J. Chromatogr. A 2014, 1370, 115–120.
Soares, R. R., Novo, P., Azevedo, A. M., Fernandes, P. et al., On-chip sample preparation and analyte quantification using a microfluidic aqueous two-phase extraction coupled with an immunoassay. Lab Chip 2014, 14, 4284–429
The acetate uptake transporter family motif "NPAPLGL(M/S)" is essential for substrate uptake
Organic acids are recognized as one of the most prevalent compounds in ecosystems, thus the transport and assimilation of these molecules represent an adaptive advantage for organisms. The AceTr family members are associated with the active transport of organic acids, namely acetate and succinate. The phylogenetic analysis shows this family is dispersed in the tree of life. However, in eukaryotes, it is almost limited to microbes, though reaching a prevalence close to 100% in fungi, with an essential role in spore development. Aiming at deepening the knowledge in this family, we studied the acetate permease AceP from Methanosarcina acetivorans, as the first functionally characterized archaeal member of this family. Furthermore, we demonstrate that the yeast Gpr1 from Yarrowia lipolytica is an acetate permease, whereas the Ady2 closest homologue in Saccharomyces cerevisiae, Fun34, has no role in acetate uptake. In this work, we describe the functional role of the AceTr conserved motif NPAPLGL(M/S). We further unveiled the role of the amino acid residues R122 and Q125 of SatP as essential for protein activity.This work was supported by the strategic program UID/BIA/04050/2013 (POCI-01-0145-FEDER-007569) and the project PTDC/BIAMIC/5184/2014 funded by national funds through the Fundacao para a Ciencia e Tecnologia (FCT) I.P. and by the European Regional Development Fund (ERDF) through the COMPETE 2020 - Programa Operacional Competitividade e Internacionalizacao (POCI); by the project EcoAgriFood: Innovative green products and processes to promote AgriFood BioEconomy (operacao NORTE-01-0145-FEDER-000009), supported by Norte Portugal Regional Operational Programme (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF). Work at ITQB NOVA was financially supported by Project LISBOA-01-0145-FEDER-007660 (Microbiologia Molecular, Estrutural e Celular) funded by FEDER funds through COMPETE2020 - Programa Operacional Competitividade e Intemacionalizacao (POCI). DR acknowledges FCT for the SFRH/BD/96166/2013 PhD grant. MSS acknowledges the Norte2020 for the UMINHO/BD/25/2016 PhD grant with the reference NORTE-08-5369-FSE-000060
Isolated ileal interposition in enteroendocrine L cells differentiation
INTRODUCTION: 
Due to the progressive nature of type 2 diabetes, its complexity and drug treatment perpetuity, there is currently a search for surgical procedures that can promote euglycemia also in non-obese patients. Diabetic patients glycemic control can be achieved by increasing the blood concentration of GLP-1, a hormone produced by L cells that are more densely concentrated in the terminal ileum. Early and extended improvement of diabetes in patients submitted to bariatric surgeries awakened the necessity of investigating the isolated ileal interposition as a surgical alternative for the treatment of diabetes. The interposition of this ileal segment to a more anterior region (proximal jejunum) can promote a greater stimulation of the L cells by poorly digested food, increasing the production of GLP-1 and reflecting on glycemic control. However, in order to consolidate the ileal interposition as a surgical treatment of diabetes it is necessary that the interposed ileum keep the same differentiation rate into L cells for a long period to justify the intervention.

AIMS: 
To investigate the isolated ileal interposition influence on the differentiation of intestinal precursor cells into enteroendocrine L cells over time.

METHODS: 
Twelve 12-week-old male Wistar rats (Rattus norvegicus albinus) of the WAB strain (heterogeneous) will be used. All animals will receive a high-calorie, high-fat diet for 16 weeks or more until they develop glucose dysmetabolism confirmed by glycemic test. They will be divided into two groups of 10 animals each: the isolated ileal interposition group (GI) and the control group (GC), comprising animals that will not be submitted to any surgical intervention. Blood samples will be collected under anesthesia at the weeks 12, 26, 36 and 44 for the determination of serum levels of glucose, insulin, GLP-1, glucagon, C-peptide and glycosilated hemoglobin. The insulin tolerance test will be performed and insulin resistance will be calculated. For the comparative analysis of the ileal precursor cells differentiation into enteroendocrine cells among the two groups, the following intestinal fragments will be collected after euthanasia: interposed ileum and remaining ileum from GI, jejunum and ileum from GC. These fragments will be analyzed by imunofluorescence and also by Real Time PCR using PCR Arrays for target genes including the main ones related to stem cell, stem cell signaling, diabetes, Wnt and Notch signaling pathways and other genes and pathways involved in the differentiation of intestinal precursor cells into enteroendocrine cells, especially GLP-1-producing L cells that play important role in euglycemia
Control of allergic rhinitis and asthma test – a formal approach to the development of a measuring tool
<p>Abstract</p> <p>Background</p> <p>The concurrent management of allergic rhinitis and asthma (ARA) has been recommended by Allergic Rhinitis and its Impact on Asthma (ARIA) guidelines. However, a tool capable of assessing simultaneously the control of upper and lower airways diseases is lacking.</p> <p>Aim</p> <p>To describe the studies conducted to design the control of ARA test (CARAT) questionnaire.</p> <p>Methods</p> <p>We performed a literature review to generate a list of potentially important items for the assessment of control of ARA. A formal consensus development process, that used an innovative web-based application, was designed – 111 experts in ARA and 60 patients participated. At the final consensus meeting, 25 primary and secondary care physicians formulated the questions and response options. A qualitative feasibility study (n = 31 patients) was conducted to evaluate the comprehensibility of the questionnaire while testing two different designs.</p> <p>Results</p> <p>Thirty-four potentially important items were identified. All the steps of the consensus process were completed in 2.5 months. The opinions of experts and patients lead to the formulation of 17 questions. At the feasibility study the instructions and wording problems were corrected and a semi-tabular format was chosen.</p> <p>Conclusion</p> <p>A tool to measure the control of allergic rhinitis and asthma was developed using a comprehensive set of methodological steps ensuring the design quality and the face and content validity. Additional validation studies to assess the psychometric properties of the questionnaire have started.</p
Vitamin A deficiency and associated factors in children in urban areas
OBJETIVO: Analisar a prevalência da deficiência de vitamina A em crianças e os fatores associados. MÉTODOS: Estudo de corte transversal de base populacional realizado com 1.211 crianças de seis a 59 meses de idade, de ambos os sexos, procedentes da área urbana de nove cidades do estado da ParaÃba, Brasil. O estado nutricional de vitamina A foi avaliado pelas concentrações séricas de retinol e presença de infecção subclÃnica avaliada pelas concentrações de proteÃna C-reativa. Foram investigadas as condições socioeconômicas, demográficas, de saneamento, além da suplementação prévia com vitamina A. Foram consideradas com deficiência de vitamina A as crianças com concentrações de retinol sérico < 0,70 µmol/L. NÃveis séricos de vitamina A < 0,70 µmol/L com prevalência ≥ 20% foram considerados como grave problema de saúde pública. Análises uni e multivaridas foram conduzidas para testar associações estatÃsticas (p < 0,05). RESULTADOS: A prevalência de deficiência de vitamina A foi de 21,8% (IC95% 19,6;24,2), mostrando associação com a presença de infecção subclÃnica e ausência de água no domicÃlio. A prevalência de deficiência de vitamina A foi de 21,8% (IC95% 19,6;24,2). Após ajuste para confundimento, a deficiência de vitamina A mostrou-se associada com a presença de infecção subclÃnica e com a ausência de água no domicÃlio. A ocorrência da deficiência de vitamina A foi quatro vezes maior (IC95% 1,49;10,16) em crianças com infecção subclÃnica e sem água no domicilio, comparativamente à s crianças sem infecção e com água no domicÃlio. CONCLUSÕES: Apesar das ações de prevenção e controle da deficiência de vitamina A, a hipovitaminose A ainda configura-se como um problema de saúde pública preocupante entre as crianças menores de cinco anos.OBJECTIVE To estimate the prevalence of vitamin A deficiency and its associated factors in children. METHODS A cross-sectional population-based study, involving 1,211 children of both sexes, aged between six and 59 months old, was carried out in the urban zone of 9 cities in the state of Paraiba, Northeastern Brazil. Vitamin A status was assessed by serum retinol levels (high performance liquid chromatography – HPLC) and subclinical infection was assessed by C-reactive protein concentrations. Socioeconomic, demographic and sanitation conditions, as well as vitamin A supplement intake, were also evaluated. Children with serum retinol concentrations RESULTS The prevalence of vitamin A deficiency was 21.8% (95%CI 19.6;24.2), showing an association with subclinical infection and lack of indoor plumbing. The prevalence of vitamin A deficiency was 21.8% (95%CI 19.6;24.2). After adjustment, vitamin A deficiency was found to be linked with subclinical infection and lack of indoor plumbing. Vitamin A deficiency was four times higher (CI95% 1.49;10.16) in children with subclinical infection whose homes were without indoor plumbing, compared to children who were not infected and with indoor plumbing in their homes. CONCLUSIONS Despite activities aimed at the prevention and control of vitamin A deficiency, hypovitaminosis A, remains a public health concern among children under five
Patient-physician discordance in assessment of adherence to inhaled controller medication: a cross-sectional analysis of two cohorts
We aimed to compare patient's and physician's ratings of inhaled medication adherence and to identify predictors of patient-physician discordance.(SFRH/BPD/115169/2016) funded by Fundação
para a Ciência e Tecnologia (FCT); ERDF (European Regional
Development Fund) through the operations: POCI-01-0145-FEDER-029130
('mINSPIRERS—mHealth to measure and improve adherence to medication
in chronic obstructive respiratory diseases—generalisation and evaluation
of gamification, peer support and advanced image processing technologies')
cofunded by the COMPETE2020 (Programa Operacional Competitividade e
Internacionalização), Portugal 2020 and by Portuguese Funds through FCT
(Fundação para a Ciência e a Tecnologia).info:eu-repo/semantics/publishedVersio
Repercussões Respiratórias no Pós – Operatório de Câncer de Mama
Introduction: Cancer is defined as a disorderly proliferation of cells that can spread and invade tissues and/or organs throughout the body, when a genetic mutation occurs, the deoxyribonucleic acid (DNA) undergoes an erroneous change of orders on how to multiply, classified as cancer cells, named according to their multiplication speed and ability to spread to other tissues. Objective: Check the respiratory repercussions in the postoperative period of breast câncer. Method: This is a descriptive, cross-sectional study with quantitative analysis, carried out with 20 female individuals in the postoperative period of breast cancer who were undergoing treatment at a Specialty Outpatient Clinic in Montes Claros - Minas Gerais. The instruments used were the MRC scale, which assesses the level of dyspnea during physical activity, cirtometry, which assesses chest expansion, and a manovacuometer, which measures respiratory muscle strength. Results: The average age of the participants was 50.40 ± 5.50, it was observed that 90.0% of the participants feel short of breath only during intense exercises, according to the MRC scale, in the cirtometry all the subjects showed a reduction in expandability thoracic. A significant decrease in respiratory muscle strength was observed, the average percentage achieved in forced inspiration was 86.77% and in forced expiration its average percentage was 71.75%. Conclusion: It is concluded that patients with breast cancer who underwent a surgical procedure may have respiratory changes, that is, the population studied showed changes in muscle strength and changes in expansion, but there was no association between the level of chest expansion and type of surgery.Introdução: O câncer é definido como uma proliferação de células desordenadas que pode se espalhar e invadir tecidos e/ou órgãos por todo o corpo, quando ocorre uma mutação genética. Objetivo: Verificar as repercussões respiratórias no pós-operatório do câncer de mama. Método: Trata-se de um estudo de caráter descritivo, corte transversal e análise quantitativa, realizado com 20 indivÃduos do sexo feminino no pós-operatório do câncer de mama que estavam em tratamento em um Ambulatório de Especialidade em Montes Claros - Minas Gerais. Os instrumentos utilizados foram a escala de MRC que avalia o nÃvel de dispneia durante atividade fÃsica, cirtometria que avalia a expansibilidade torácica e manovacuômetro que mensura a força muscular respiratória. Resultados: A idade média das participantes foi de 50,40 ± 5,50, observou-se que 90,0% das participantes sente falta de ar só durante exercÃcios intensos, segundo a escala de MRC, na cirtometria todos os sujeitos apresentaram redução da expansibilidade torácica. Foi observado uma diminuição significativa na força muscular respiratória, a média percentual alcançada na inspiração forçada foi de 86,77% e na expiração forçada sua média percentual foi de 71,75%. Conclusão: Conclui-se que pacientes portadoras de CA de mama que foram submetidas a um procedimento cirúrgico podem apresentar alterações respiratórias, ou seja, a população estudada apresentou alteração de força muscular e alteração da expansibilidade, porém não houve associação entre nÃvel de expansibilidade torácica e tipo de cirurgia.
 
Determinants of intensive insulin therapeutic regimens in patients with type 1 diabetes: data from a nationwide multicenter survey in Brazil
Background: To evaluate the determinants of intensive insulin regimens (ITs) in patients with type 1 diabetes (T1D).Methods: This multicenter study was conducted between December 2008 and December 2010 in 28 public clinics in 20 Brazilian cities. Data were obtained from 3,591 patients (56.0% female, 57.1% Caucasian). Insulin regimens were classified as follows: group 1, conventional therapy (CT) (intermediate human insulin, one to two injections daily); group 2 (three or more insulin injections of intermediate plus regular human insulin); group 3 (three or more insulin injections of intermediate human insulin plus short-acting insulin analogues); group 4, basal-bolus (one or two insulin injections of long-acting plus short-acting insulin analogues or regular insulin); and group 5, basal-bolus with continuous subcutaneous insulin infusion (CSII). Groups 2 to 5 were considered IT groups.Results: We obtained complete data from 2,961 patients. Combined intermediate plus regular human insulin was the most used therapeutic regimen. CSII was used by 37 (1.2%) patients and IT by 2,669 (90.2%) patients. More patients on IT performed self-monitoring of blood glucose and were treated at the tertiary care level compared to CT patients (p < 0.001). the majority of patients from all groups had HbA1c levels above the target. Overweight or obesity was not associated with insulin regimen. Logistic regression analysis showed that economic status, age, ethnicity, and level of care were associated with IT (p < 0.001).Conclusions: Given the prevalence of intensive treatment for T1D in Brazil, more effective therapeutic strategies are needed for long term-health benefits.Farmanguinhos/Fundacao Oswaldo Cruz/National Health MinistryBrazilian Diabetes SocietyFundacao do Amparo a Pesquisa do Estado do Rio de JaneiroConselho Nacional de Desenvolvimento CientÃfico e Tecnológico (CNPq)Univ Estado Rio de Janeiro, Unit Diabet, BR-20551030 Rio de Janeiro, BrazilBaurus Diabet Assoc, São Paulo, BrazilFed Univ São Paulo State, Diabet Unit, São Paulo, BrazilFed Univ Hosp Porto Alegre, Porto Alegre, BrazilUniv Hosp São Paulo, Diabet Unit, São Paulo, BrazilUniv Fed Rio de Janeiro, Rio de Janeiro, BrazilUniv Fed Ceara, Fortaleza, Ceara, BrazilSanta Casa Misericordia, Belo Horizonte, MG, BrazilSanta Casa Misericordia São Paulo, São Paulo, BrazilUniv Fed Amazonas, Manaus, Amazonas, BrazilHosp Geral de Bonsucesso, Rio de Janeiro, BrazilHosp Univ Clementino Fraga Filho IPPMG, Rio de Janeiro, BrazilUniv Hosp São Paulo, São Paulo, BrazilFac Ciencias Med Santa Casa São Paulo, São Paulo, BrazilUniv São Paulo, Inst Crianca, Hosp Clin, São Paulo, BrazilUniv São Paulo, Fac Med Ribeirao Preto, Hosp Clin, Ribeirao Preto, BrazilAmbulatorio Fac Estadual Med Sao Jose Rio Preto, Ribeirao Preto, BrazilEscola Paulista Med, Ctr Diabet, Ribeirao Preto, BrazilClin Endocrinol Santa Casa Belo Horizonte, Belo Horizonte, MG, BrazilUniv Estadual Londrina, Londrina, BrazilUniv Fed Parana, Hosp Clin, Porto Alegre, RS, BrazilInst Crianca Com Diabet Rio Grande Sul, Rio Grande Do Sul, RS, BrazilGrp Hosp Conceicao, Inst Crianca Com Diabet, Porto Alegre, RS, BrazilHosp Univ Santa Catarina, Florianopolis, SC, BrazilInst Diabet Endocrinol Joinville, Joinville, BrazilHosp Reg Taguatinga, Brasilia, DF, BrazilHosp Geral Goiania, Goiania, Go, BrazilCtr Diabet & Endocrinol Estado Bahia, Goiania, Go, BrazilUniv Fed Maranhao, Sao Luis, BrazilCtr Integrado Diabet & Hipertensao Ceara, Fortaleza, Ceara, BrazilUniv Fed Sergipe, Aracaju, BrazilHosp Univ Alcides Carneiro, Campina Grande, BrazilHosp Univ Joao de Barros Barreto, Belem, Para, BrazilFed Univ São Paulo State, Diabet Unit, São Paulo, BrazilUniv Hosp São Paulo, Diabet Unit, São Paulo, BrazilUniv Hosp São Paulo, São Paulo, BrazilEscola Paulista Med, Ctr Diabet, Ribeirao Preto, BrazilWeb of Scienc
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