Purification of plasmid DNA vectors by aqueous two-phase extraction and hydrophobic interaction chromatography

The current study explores the possibility of using a polyethyleneglycol(PEG)/ammonium sulphate aqueous two-phase system (ATPS) as an early step in a process for the purification of a model 6.1 kbp plasmid DNA (pDNA) vector. Neutralised alkaline lysates were fed directly to ATPS. Conditions were selected to direct pDNA towards the salt-rich bottom phase, so that this stream could be subsequently processed by hydrophobic interaction chromatography (HIC). Screening of the best conditions for ATPS extraction was performed using three PEG molecular weights (300, 400, 600) and varying the tie-line length, phase volume ratio and lysate load. For a 20 % (w/w) lysate load, the best results were obtained with PEG 600 using the shortest tie-line (38.16 % w/w). By further manipulating the system composition along this tie-line in order to obtain a top/bottom phase volume ratio of 9.3 (35 % w/w PEG 600, 6% w/w NH4)2SO4), it was possible to recover 100 % of pDNA in the bottom phase with a 3-fold increase in concentration. Further increase in the lysate load up to 40 %(w/w) with this system resulted in a 8-fold increase in pDNA concentration, but with a yield loss of 15 %. The ATPS extraction was integrated with HIC and the overall process compared with a previously defined process that uses sequential precipitations with isopropanol and ammonium sulphate prior to HIC. Although the final yield is lower in the ATPS-based process the purity grade of the final pDNA product is higher. This shows that it is possible to substitute the time-consuming two-step precipitation procedure by a simple ATPS extraction.Portuguese Ministry of Science and Technology - POCTI/BIO/47245/2002

Uso de modelos no lineales para el ajuste de la curva de crecimiento de corderos segureños a la edad de sacrificio

El objetivo de este trabajo fue estudiar el patrón de crecimiento de corderos segureños desde el nacimiento a la edad de sacrificio establecida, según los criterios del esquema de selección de la raza, a los 70 días de vida; todo ello con la finalidad de predecir algunas características de esos modelos para evaluar los desarrollos corporales de machos y hembras. Para el ajuste global de las curvas de crecimiento se utilizaron tres funciones matemáticas, que fueron la de Compenz, Van Berlalanffy y la curva logística. La base de información utilizada constaba de un total de 25.483 pesadas realizadas en el Núcleo de control de rendimientos entre los años comprendidos entre 1998 y 2004. Para el ajuste de los modelos se utilizó el procedimiento NLIN de SAS. Los modelos utilizados independientemente del sexo del cordero nos proporcionaron una buena calidad de ajuste a los pesos para ambos sexos, indicando que las hembras alcanzan la madurez en edades más precoces, mientras que los machos, presentan un peso adulto más elevado. Para los controles efectuados en ambos sexos el modelo que obtuvo el mejor ajuste (menor valor de Cuadrado Medio del Error) fue el correspondiente a la curva logística

Unpacking distinction within mobility : social prestige and international students

Author thanks the Social Sciences and Humanities Research Council of Canada (SSHRC) for their funding on this projecThis paper investigates the complex ways in which young people engage in social distinction within international mobility. The study offers novel conceptual and empirical insights by examining how distinction and social advantage is reproduced through short‐term student mobility from the Global North to the Global South. In doing so, it elucidates the iterative process of distinction‐making within mobility and argues that young mobile people negotiate a tension between different forms of distinction. Specifically, it unpacks and conceptualises distinction into dual categories—collective and individual—and suggests that students alternate and waver between these categories in order to both validate and elevate their position within a mobility hierarchy. The paper also considers how particular places are viewed as more distinctive and affording greater gains in cultural and symbolic capital. It concludes with future interrogations and ways forward for research on international mobility and distinction.PostprintPeer reviewe

Intima-Media Thickness and Pulsatility Index of Common Carotid Arteries in Acute Ischaemic Stroke Patients with Diabetes Mellitus.

Ultrasonographic parameters such as the common carotid artery (CCA) pulsatility index (PI) and CCA intima-media thickness (IMT) have been associated with an increased mortality and risk of recurrent stroke, respectively. We hypothesized that these ultrasonographic parameters may be useful for monitoring diabetic patients after an acute stroke. We analysed retrospective data of consecutive acute ischaemic stroke patients from the ASTRAL registry who underwent pre-cerebral ultrasonographic evaluation within 7 days of symptom onset. We compared clinical, demographic, radiological and ultrasonographic parameters in diabetic versus non-diabetic patients (univariable and multivariable analyses) and the association of these parameters with CCA PI and CCA IMT. We analysed 1507 carotid duplex ultrasound examinations from patients with a median age of 74 years. Cardiovascular co-morbidities, including hypertension, hypercholesterolemia, obstructive sleep apnoea syndrome, higher body-mass index (BMI) and peripheral artery disease, were associated with diabetes mellitus (DM). Diabetics were more often under antiplatelet therapy and had atrial fibrillation at admission. Diabetic patients showed an increased CCA PI and IMT in line with more atherosclerotic changes on acute CTA compared to non-diabetic patients. Taking IMT as the dependent variable in a second analysis, DM, higher age, hypertension, smoking and CCA PI were associated with higher IMT. Taking CCA PI as the dependent variable in a third analysis, DM, higher age and higher NIHSS at admission were associated with higher CCA PI values. Increased IMT was also associated with higher PI. We show that CCA PI and IMT are higher in diabetic patients in the first week after an initial stroke

Elaboration and characterization of snack bars made with ingredients from the Amazon.

Como uma alternativa para as pessoas que procuram opções para uma alimentação saudável, as barras de cereais foram lançadas no mercado. Elas são populares como alimentos portáteis e podem ser consumidas entre as refeições. Este trabalho teve como objetivo desenvolver e determinar as variáveis físicas, físico-químicas, microbiológicas e sensoriais de barras de cereais à base de farinha de tapioca, castanha-do-brasil e polpas de frutas regionais (açaí, cupuaçu, muruci e taperebá). A concentração preferida de polpa na barra sabor açaí foi de 10% e nas barras sabor cupuaçu, muruci e taperebá de 15%. O índice de aceitação da barra sabor açaí foi superior a 70% nos atributos aparência, cor, textura e impressão global e inferior no sabor. Este comportamento pode estar relacionado à cultura de alguns provadores, os quais têm o hábito de consumir a polpa de açaí sem adição de qualquer outro ingrediente que possa mascarar o sabor intrínseco e peculiar do fruto. As barras sabor cupuaçu e muruci, por apresentarem maior aceitação sensorial, quando comparadas às barras sabor açaí e taperebá, têm melhores perspectivas de mercado caso sejam comercializadas

Iodine Intake and Related Cognitive Function Impairments in Elementary Schoolchildren

Iodine deficiency, the most common cause of preventable mental impairment worldwide, has been linked to poorer intellectual function in several studies. However, to our knowledge, no studies have been performed in moderate iodine-deficient schoolchildren using the complete form of Wechsler Intelligence Scale for Children (WISC-III; Portuguese version). The main purpose of this study was to ascertain whether moderate iodine deficiency would affect the cognitive function of schoolchildren (7–11 years old; 3rd and 4th grades). Raven’s Colored Progressive Matrices (CPM; Portuguese version) were used for measuring the intelligence quotient (IQ) of the total population (n = 256; median UIC = 66.2 μg/L), and the WISC-III was used to study two selected subgroups: one moderately iodine-deficient (n = 30) and the other with adequate iodine intake (n = 30). WISC-III was shown to be the prime instrument for cognitive function assessment among moderate iodine-deficient schoolchildren; this subgroup had a Full-Scale IQ 15.13 points lower than the adequate iodine intake subgroup, with a magnitude effect of d = 0.7 (p = 0.013). Significant differences were also registered in 6 of the 13 Verbal-Performance IQ subtests. Moderate iodine deficiency has a substantial impact on mental development and cognitive functioning of schoolchildren, with significant impairment in both Performance IQ and Verbal IQ spectrum, adversely impacting their educational performance.Diana Linhares was supported by a post-doc fellowship from the Fundo Regional da Ciencia (Regional Government of the Azores) (M3.1.a/F/004/2018). This work was supported by FCT-Fundacao para a Ciencia e a Tecnologia, within the project UIDP/00643/2020.info:eu-repo/semantics/publishedVersio

How to Treat a Signal? Current Basis for RET-Genotype-Oriented Choice of Kinase Inhibitors for the Treatment of Medullary Thyroid Cancer

The significance of RET in thyroid cancer comes from solid evidence that, when inherited, an RET activating mutation primes C-cells to transform into medullary carcinomas. Moreover, environmental exposure to radiation also induces rearranged transforming RET “isoforms” that are found in papillary thyroid cancer. The RET gene codes for a tyrosine kinase receptor that targets a diverse set of intracellular signaling pathways. The nature of RET point mutations predicts differences in the mechanisms by which the receptor becomes activated and correlates with different forms of clinical presentation, age of onset, and biological aggressiveness. A number of RET-targeting Tyrosine Kinase Inhibitors (TKIs) are currently undergoing clinical trials to evaluate their effectiveness in the treatment of thyroid cancer, and it is conceivable that the RET genotype may also influence response to these compounds. The question that now emerges is whether, in the future, the rational for treatment of refractory thyroid cancer will be based on the management of an abnormal RET signal. In this paper we address the RET-targeting TKIs and review studies about the signaling properties of distinct RET mutants as a means to predict response and design combinatorial therapies for the soon to be available TKIs

LRP1B (low density lipoprotein receptor-related protein 1B)

Review on LRP1B, with data on DNA/RNA, on the protein encoded and where the gene is implicated

Análisis de efectos fijos sobre el comportamiento productivo de la raza caprina murciano granadina en el núcleo de control de Almería

El objetivo del presente estudio es determinar la influencia del efecto año, época de parto, número de lactación y ganadería sobre la producción de leche estandarizada a 240 días en cabras de raza Murciano-Granadina. La base información deriva del control lechero oficial desarrollado durante quince años en el núcleo de control de Almería de la Asociación Nacional de Criadores de Caprino de Raza Murciano-Granadina. Los resultados mostraron que la producción de leche se encuentra fuertemente influenciada por todos los efectos estudiados, hecho que resulta muy interesante en una raza principalmente explotada en condiciones semiextensivas y con una elevada dependencia ambiental

Improvement of DNA minicircle production by optimization of the secondary structure of the 5′-UTR of ParA resolvase

The use of minicircles in gene therapy applications is dependent on the availability of high-producer cell systems. In order to improve the performance of minicircle production in Escherichia coli by ParA resolvase-mediated in vivo recombination, we focus on the 5′ untranslated region (5′-UTR) of parA messenger RNA (mRNA). The arabinose-inducible P[subscript BAD]/araC promoter controls ParA expression and strains with improved arabinose uptake are used. The 27-nucleotide-long 5′-UTR of parA mRNA was optimized using a predictive thermodynamic model. An analysis of original and optimized mRNA subsequences predicted a decrease of 8.6–14.9 kcal/mol in the change in Gibbs free energy upon assembly of the 30S ribosome complex with the mRNA subsequences, indicating a more stable mRNA-rRNA complex and enabling a higher (48–817-fold) translation initiation rate. No effect of the 5′-UTR was detected when ParA was expressed from a low-copy number plasmid (∼14 copies/cell), with full recombination obtained within 2 h. However, when the parA gene was inserted in the bacterial chromosome, a faster and more effective recombination was obtained with the optimized 5′-UTR. Interestingly, the amount of this transcript was 2.6–3-fold higher when compared with the transcript generated from the original sequence, highlighting that 5′-UTR affects the level of the transcript. A Western blot analysis confirmed that E. coli synthesized higher amounts of ParA with the new 5′-UTR (∼1.8 ± 0.7-fold). Overall, these results show that the improvements made in the 5′-UTR can lead to a more efficient translation and hence to faster and more efficient minicircle generation.MIT-Portugal ProgramFundação para a Ciência e a Tecnologia (PhD grant SFRH/BD/33786/2009