Novel LNA probe-based assay for the A1 and A2 identification of ß-casein gene in milk samples.

The rising consumption of A2 milk and its derivatives in recent years has garnered attention from both consumers and producers, mainly due its possible health benefits, such as enhanced digestion and easier absorption. Thus, a novel real-time PCR using a combination of locked nucleic acid modified (LNA) conjugated probes was developed to genotype A1 and A2 alleles of ß-casein gene (CSN2) and to detect and quantify the A1 presence in A2 samples. The limit of detection for each probe (A1 and A2) was evaluated using decreasing serial dilutions. Besides, the sensitivity of A1 allele detection in the A2 samples was also tested. The limits of detection of A1 and A2 alleles were 6 copies, while for A1 allele detection in A2 samples was 7.5 copies (1%). The LNA-probe based method was found to be rapid, robust, highly sensitive, cost effective, and can be employed as screening test to certificate the A2 dairy products.

Energy Efficiency Analysis of MIMO Wideband RF Front-End Receivers.

Energy-efficiency is crucial for modern radio-frequency (RF) receivers dedicated to Internet of Things applications. Energy-efficiency enhancements could be achieved by lowering the power consumption of integrated circuits, using antenna diversity or even with an association of both strategies. This paper compares two wideband RF front-end architectures, based on conventional low-noise amplifiers (LNA) and low-noise transconductance amplifiers (LNTA) with N-path filters, operating with three transmission schemes: single antenna, antenna selection and singular value decomposition beamforming. Our results show that the energy-efficiency behavior varies depending on the required communication link conditions, distance between nodes and metrics from the front-end receivers. For short-range scenarios, LNA presents the best performance in terms of energy-efficiency mainly due to its very low power consumption. With the increasing of the communication distance, the very low noise figure provided by N-path LNTA-based architectures outperforms the power consumption issue, yielding higher energy-efficiency for all transmission schemes. In addition, the selected front-end architecture depends on the number of active antennas at the receiver. Hence, we can observe that low noise figure is more important with a few active antennas at the receiver, while low power consumption becomes more important when the number of active RF chains at the receiver increases.

Reduce proliferation of human bone marrow cells from acute myeloblastic leukemia with minimally differentiation by blocking lncRNA PVT1.

PURPOSE: Acute myeloblastic leukemia with minimally differentiation (AML-M0) is a subtype of acute leukemia with poor prognosis. The recent studies have shown that long non-coding RNAs (lncRNAs) play an important role in different cellular processes, such as cell cycle control and proliferation. Plasmacytoma variant translocation 1 (PVT1) is one of those lncRNAs that is significantly upregulated in AML. LncRNAs could be downregulated or blocked by locked nucleic acids (LNA) which are oligonucleotide strands. METHODS: In this study, lncRNA PVT1 was blocked by antisense LNA GapmeRs in human bone marrow cancerous blast cells. Cells were transfected with PVT1 antisense LNA GapmeRs at 24, 48, and 72 h post-transfection. Quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) was accomplished to evaluate the PVT1 and c-Myc expression. Cell viability was evaluated by MTT assay, and apoptosis and necrosis were assessed by Annexin V/propidium iodide staining assay. RESULTS: The results of this study indicated that the downregulation of PVT1 in blast cells could induce apoptosis, and necrosis and reduce cell viability. The expression of c-Myc was downregulated by blockage of PVT1 and it shows that the expression of these two genes are correlated. CONCLUSION: The findings declare that inhibition of PVT1 could be a new target in the treatment of AML-M0 and help to approach more to treatments with fewer side effects.

Estandarización de un protocolo para Northern blot no radioactivo usado en la detección de pequeños RNA en células Vero / Standardization of Northern blot non-radioactive protocol used in the detection of small RNAs in Vero line cells

El interés en la detección, identificación, y caracterización funcional de los pequeños RNAs no codificantes (sRNAs), ha generado la necesidad de optimizar las metodologías comúnmente usadas en su detección, la reacción en cadena de la polimerasa cuantitativa (RT-qPCR) y Northern blot, con el fin de que sean más sensibles y específicas. A pesar de la baja sensibilidad del Northern blot, esta metodología continúa siendo de uso común en la detección de sRNAs porque permite detectar el RNA pequeño así como a sus precursores, razón por la cual se usa como una metodología complementaria en este tipo de investigaciones. En este trabajo se describe la implementación de un nuevo protocolo para Northern blot no radioactivo, con modificaciones dirigidas a mejorar su sensibilidad y especificidad. El diseños de la sonda con la tecnología LNA, el marcaje de esta con Digoxigenina y por último la fijación del RNA a la membrana mediante 1-Ethyl-3-(-3-dimethylaminopropyl) carboniimide (EDC) y finalmente se discuten los fundamentos teóricos de estos cambios.

The interest in detection, identification and functional characterization of small non-coding RNAs (snRNAs), has generated the need to optimize the methodologies commonly used in its detection in specificity and sensitivity, The Quantitative reverse transcription PCR (RT-qPCR) and Northern blot. Even though the low sensitivity of Northern blot, this method continues to be commonly used in the sRNAs, because its capacity to detect the sRNA and its precursor, which is the reason why Northern blot is used as complementary method in this sort of Research. This work describes the implementation of an innovative non-radioactive Northern blot protocol, with modifications that improving the sensibility and specificity, with the discussion of the theoretical foundations of such modifications.

Distribution of HNA and LNA bacterial groups in the Southwest Atlantic Ocean

Bacterioplankton was studied in a large area of Southwest Atlantic Ocean between 13 and 25ºS and 28 and 42ºW. Samples were collected in 108 stations at 20 m depth. Bacteria were enumerated by flow cytometry after nucleic acid staining with syto13 and two subgroups were differentiated: low nucleic acid content (LNA) and high nucleic acid content (HNA) bacteria. Total bacterial numbers varied from 0.37 to 5.53 10(5) cells mL-1. HNA cells represented 15 to 70% of the total number while LNA cells represented 30 to 85%. Heterotrophic bacterial production was determined by incorporation of tritiated leucine and ranged from 2.7 to 171.07 ng C L-1 h-1. No significant correlation was found between abundance and production. Nevertheless with support of multivariate analysis between bacterial abundance, bacterial production, chlorophyll a and other oceanographic data the distribution of the groups in two different oceanic provinces could be explained by nutrient availability. HNA bacteria accounted for the high percentage of cells found in the area north of 19ºS, linked to higher temperature waters and riverine nutrients inputs. LNA bacteria were the dominant cells south of this latitude and were correlated to the higher values of nitrate found for the same area.

Um estudo do bacterioplâncton foi realizado numa área extensa do Oceano Atlântico Sudoeste entre 13 e 25ºS e 28 e 42ºW. As amostras foram coletadas em 108 estações oceanográficas a 20 m de profundidade. A abundância bacteriana foi determinada por citometria de fluxo após coloração dos ácidos nucléicos com Syto13. Dois grupos de bactérias foram enumerados e distinguidos: bactérias com alto conteúdo de ácidos nucleicos (HNA) e bactérias com baixo conteúdo de ácidos nucleicos (LNA). O número de bactérias variou de 0,37 a 5,53 10(5) células mL-1. As células HNA representaram de 15 a 70% da abundância total enquanto as células LNA representaram de 30 a 85%. A produção bacteriana foi determinada por incorporação de leucina tritiada e variou de 2,7 a 171,07 ng C L-1 h-1. A correlação entre abundância e produção bacterianas não foi significativa. Entretanto uma análise multivariada realizada entre abundância, produção, clorofila a e outros dados oceanográficos revelou que a distribuição dos dois grupos em diferentes províncias oceânicas pode ser atribuída a disponibilidade de nutrientes. As bactérias HNA foram responsáveis pelo maior percentual de células na área ao norte de 19ºS e estiveram relacionadas às águas quentes e aos nutrientes de origem pluvial. As bactérias LNA foram dominantes ao sul dessa latitude e estiveram relacionadas à disponibilidade de nitrato cujos valores foram mais altos nessa região.