Wavelet based Watermarking approach in the Compressive Sensing Scenario

Due to the wide distribution and usage of digital media, an important issue is protection of the digital content. There is a number of algorithms and techniques developed for the digital watermarking.In this paper, the invisible image watermark procedure is considered. Watermark is created as a pseudo random sequence, embedded in the certain region of the image, obtained using Haar wavelet decomposition. Generally, the watermarking procedure should be robust to the various attacks-filtering, noise etc. Here we assume the Compressive sensing scenario as a new signal processing technique that may influence the robustness. The focus of this paper was the possibility of the watermark detection under Compressive Sensing attack with different number of available image coefficients. The quality of the reconstructed images has been evaluated using Peak Signal to Noise Ratio (PSNR).The theory is supported with experimental results

Blood Brain-Derived Neurotrophic Factor (BDNF) and Major Depression:Do We Have a Translational Perspective?

Major depressive disorder (MDD) affects millions of people worldwide and is a leading cause of disability. Several theories have been proposed to explain its pathological mechanisms, and the "neurotrophin hypothesis of depression" involves one of the most relevant pathways. Brain-derived neurotrophic factor (BDNF) is an important neurotrophin, and it has been extensively investigated in both experimental models and clinical studies of MDD. Robust empirical findings have indicated an association between increased BDNF gene expression and peripheral concentration with improved neuronal plasticity and neurogenesis. Additionally, several studies have indicated the blunt expression of BDNF in carriers of the Val66Met gene polymorphism and lower blood BDNF (serum or plasma) levels in depressed individuals. Clinical trials have yielded mixed results with different treatment options, peripheral blood BDNF measurement techniques, and time of observation. Previous meta-analyses of MDD treatment have indicated that antidepressants and electroconvulsive therapy showed higher levels of blood BDNF after treatment but not with physical exercise, psychotherapy, or direct current stimulation. Moreover, the rapid-acting antidepressant ketamine has presented an early increase in blood BDNF concentration. Although evidence has pointed to increased levels of BDNF after antidepressant therapy, several factors, such as heterogeneous results, low sample size, publication bias, and different BDNF measurements (serum or plasma), pose a challenge in the interpretation of the relation between peripheral blood BDNF and MDD. These potential gaps in the literature have not been properly addressed in previous narrative reviews. In this review, current evidence regarding BDNF function, genetics and epigenetics, expression, and results from clinical trials is summarized, putting the literature into a translational perspective on MDD. In general, blood BDNF cannot be recommended for use as a biomarker in clinical practice. Moreover, future studies should expand the evidence with larger samples, use the serum or serum: whole blood concentration of BDNF as a more accurate measure of peripheral BDNF, and compare its change upon different treatment modalities of MDD

Fatores associados ao início da vida sexual e o uso de preservativo entre adolescentes da Ilha de Santiago, Cabo Verde, África Ocidental

Foram analisados fatores associados ao início da vida sexual de adolescentes na Ilha de Santiago, Cabo Verde, segundo sexo. Estudo realizado com amostra probabilística e representativa de 768 adolescentes, age 13-17 anos, de escolas secundárias públicas da Ilha de Santiago em 2007. A associação foi testada pelo teste de proporção, qui-quadrado de Pearson ou Fisher e regressão logística. Nos rapazes, os fatores associados ao início da vida sexual foram: idade maior que 14 anos, ser católico e consumo de bebidas alcoólicas. Para meninas: escolaridade maior que nove anos e ter parceiro afetivo-sexual. Ao contrário de outros contextos da África Subsaariana, foram constatadas taxas elevadas de uso de preservativo por adolescentes no início da vida sexual. Os adolescentes podem iniciar a vida sexual de maneira mais segura se tiverem informação, educação sexual e acesso a métodos de prevenção à gravidez e às DST. Este artigo oferece elementos para a reflexão sobre o delineamento de políticas de redução da vulnerabilidade dos jovens às DST/AIDS e sobre os limites e desafios da promoção do uso do preservativo e educação sexual, focando as relações desiguais de gêneroThe current study focuses on factors associated with sexual initiation and condom use among teenagers on Santiago Island, Cape Verde, according to gender. This was a representative, probabilistic sample of 13-to-17-year-olds (n = 768) attending public secondary schools on Santiago Island in 2007. Associations were tested by test of proportion, Pearson's chi-square, or Fisher's exact test and logistic regression. Factors related to sexual initiation among boys were: age over 14 years, Catholic religion, and alcohol consumption. For girls, the factors included: > 9 years of schooling and involvement in an affective-sexual relationship. Unlike other Sub-Saharan countries, this study showed a high prevalence of condom use during initial sexual activity. Adolescents are able to safely begin sexually active life if they have access to information, sex education, and other STD prevention and contraceptive methods. This study provides insights on the development of policies to reduce the vulnerability of the young population to STD/AIDS and the limits and challenges related to the promotion of condom use and sex education, focusing on unequal gender relation

Variantes de Smqnr de isolados clínicos de Stenotrophomonas maltophilia no Brasil

SUMMARY Stenotrophomonas maltophilia contains a novel chromosomally-encoded qnr gene named Smqnr that contributes to low intrinsic resistance to quinolone. We described Smqnr in 13 clinical isolates of S. maltophilia from two Brazilian hospitals, over a 2-year period. The strains were identified by API 20 NE (bioMérieux, France). Susceptibility by microdilution method to trimetroprim/sulfamethoxazole, ciprofloxacin, levofloxacin, minocycline, ceftazidime, chloramphenicol and ticarcillin/clavulanate was performed according to CLSI. PCR detection of Smqnr gene was carried out. The sequence of Smqnr was compared with those deposited in GenBank. Pulsed-field gel electrophoresis (PFGE) of all strains was performed. Thirteen Smqnr positives isolates were sequenced and three novel variants of Smqnr were identified. All 13 Smqnr isolates had distinguishable patterns by PFGE. This is the first report of Smqnr in S. maltophilia isolated in Brazil.RESUMO S. maltophilia contem um novo gene qnr cromossômico denominado Smqnr que contribui para baixa resistência intrínseca a quinolonas. Descrevemos Smqnr em 13 isolados clínicos de S. maltophilia de dois hospitais brasileiros, ao longo do período de dois anos. Os isolados foram identificados pela API 20 NE (bioMérieux, França). Susceptibilidade pelo método de microdiluição dos seguintes antibióticos trimetroprim/sulfametoxazol, ciprofloxacina, levofloxacina, minociclina, ceftazidima, cloranfenicol e ticarcilina/clavulanato foi realizada segundo o CLSI. Detecção do gene de Smqnr foi realizada por PCR. A sequência de Smqnr foi comparada com aquelas depositadas no GenBank. Foi realizada eletroforese em gel de campo pulsado (PFGE) de todos os isolados. Treze isolados contendo Smqnr foram sequenciados e identificados três variantes do gene Smqnr. Todos os 13 isolados de Smqnr apresentaram diferentes padrões por PFGE. Este é o primeiro relato de Smqnr em isolados de S. maltophilia no Brasil

A novel high-content immunofluorescence assay as a tool to identify at the single cell level γ-globin inducing compounds

The identification of drugs capable of reactivating γ-globin to ameliorate β-thalassemia and Sickle Cell anemia is still a challenge, as available γ-globin inducers still have limited clinical indications. High-throughput screenings (HTS) aimed to identify new potentially therapeutic drugs require suitable first-step-screening methods combining the possibility to detect variation in the γ/β globin ratio with the robustness of a cell line. We took advantage of a K562 cell line variant expressing β-globin (β-K562) to set up a new multiplexed high-content immunofluorescence assay for the quantification of γ-and β-globin content at single-cell level. The assay was validated by using the known globin inducers hemin, hydroxyurea and butyric acid and further tested in a pilot screening that confirmed HDACs as targets for γ-globin induction (as proved by siRNA-mediated HDAC3 knockdown and by treatment with HDACs inhibitors entinostat and dacinostat) and identified Heme-oxygenases as novel candidate targets for γ-globin induction. Indeed, Heme-oxygenase2 siRNA knockdown as well as its inhibition by Tin protoporphyrin-IX (TinPPIX) greatly increased γ-globin expression. This result is particularly interesting as several metalloporphyrins have already been developed for clinical uses and could be tested (alone or in combination with other drugs) to improve pharmacological γ-globin reactivation for the treatment of β-hemoglobinopathie

Azidotimidina (AZT) na expressão gênica e na síntese proteíca da telomerase em células de melanoma metastático humano / Azidothymidine (AZT) in gene expression and protein synthesis of telomerase in human metastatic melanoma cells

Introdução: As evidências demonstram que o processo de transformação maligna envolve várias alterações genéticas, tanto em melanoma como em outras neoplasias, os quais modificam processos celulares importantes, dentre eles, o encurtamento dos telômeros. A enzima responsável pela síntese do telômero é conhecida como telomerase, a qual é encontrada em diversas linhagens e tumores humanos. A telomerase é reativada pelas células imortalizadas, sugerindo uma ligação com sua progressão e que um agente inibidor dessa enzima, como a azidotimidina (AZT), poderia ser uma droga antitumoral efetiva. Objetivo: Avaliar a ação do AZT na expressão gênica e na síntese proteica da telomerase nas células de melanomas metastático. Método: As células provenientes de amostras de tecidos e células de melanoma Hs839T de pacientes foram utilizadas. A avaliação da proliferação celular foi realizada por microtitulação colorimétrica e a caracterização das células, a marcação para P53, a apoptose e a detecção da telomerase foram realizadas por citometria de fluxo e amplificação gênica da telomerase por PCR RT. Resultados: A ação do AZT diminuiu a expressão gênica da telomerase nas células estudadas com diferença estatisticamente significante, mas não a síntese proteica da enzima. Conclusão: O AZT induziu a diminuição da expressão gênica da telomerase sem promover alteração na síntese dessa enzima em células de melanoma metastático humano

Azidotimidina (AZT) na expressão gênica e na síntese proteíca da telomerase em células de melanoma metastático humano / Azidothymidine (AZT) in gene expression and protein synthesis of telomerase in human metastatic melanoma cells

Introdução: As evidências demonstram que o processo de transformação maligna envolve várias alterações genéticas, tanto em melanoma como em outras neoplasias, os quais modificam processos celulares importantes, dentre eles, o encurtamento dos telômeros. A enzima responsável pela síntese do telômero é conhecida como telomerase, a qual é encontrada em diversas linhagens e tumores humanos. A telomerase é reativada pelas células imortalizadas, sugerindo uma ligação com sua progressão e que um agente inibidor dessa enzima, como a azidotimidina (AZT), poderia ser uma droga antitumoral efetiva. Objetivo: Avaliar a ação do AZT na expressão gênica e na síntese proteica da telomerase nas células de melanomas metastático. Método: As células provenientes de amostras de tecidos e células de melanoma Hs839T de pacientes foram utilizadas. A avaliação da proliferação celular foi realizada por microtitulação colorimétrica e a caracterização das células, a marcação para P53, a apoptose e a detecção da telomerase foram realizadas por citometria de fluxo e amplificação gênica da telomerase por PCR RT. Resultados: A ação do AZT diminuiu a expressão gênica da telomerase nas células estudadas com diferença estatisticamente significante, mas não a síntese proteica da enzima. Conclusão: O AZT induziu a diminuição da expressão gênica da telomerase sem promover alteração na síntese dessa enzima em células de melanoma metastático humano

Probing black hole accretion tracks, scaling relations, and radiative efficiencies from stacked X-ray active galactic nuclei

The masses of supermassive black holes at the centres of local galaxies appear to be tightly correlated with the mass and velocity dispersions of their galactic hosts. However, the local Mbh–Mstar relation inferred from dynamically measured inactive black holes is up to an order-of-magnitude higher than some estimates from active black holes, and recent work suggests that this discrepancy arises from selection bias on the sample of dynamical black hole mass measurements. In this work, we combine X-ray measurements of the mean black hole accretion luminosity as a function of stellar mass and redshift with empirical models of galaxy stellar mass growth, integrating over time to predict the evolving Mbh–Mstar relation. The implied relation is nearly independent of redshift, indicating that stellar and black hole masses grow, on average, at similar rates. Matching the de-biased local Mbh–Mstar relation requires a mean radiative efficiency ε ≳ 0.15, in line with theoretical expectations for accretion on to spinning black holes. However, matching the ‘raw’ observed relation for inactive black holes requires ε ∼ 0.02, far below theoretical expectations. This result provides independent evidence for selection bias in dynamically estimated black hole masses, a conclusion that is robust to uncertainties in bolometric corrections, obscured active black hole fractions, and kinetic accretion efficiency. For our fiducial assumptions, they favour moderate-to-rapid spins of typical supermassive black holes, to achieve ε ∼ 0.12–0.20. Our approach has similarities to the classic Soltan analysis, but by using galaxy-based data instead of integrated quantities we are able to focus on regimes where observational uncertainties are minimized

Multi-Scale Simulations Provide Supporting Evidence for the Hypothesis of Intramolecular Protein Translocation in GroEL/GroES Complexes

The biological function of chaperone complexes is to assist the folding of non-native proteins. The widely studied GroEL chaperonin is a double-barreled complex that can trap non-native proteins in one of its two barrels. The ATP-driven binding of a GroES cap then results in a major structural change of the chamber where the substrate is trapped and initiates a refolding attempt. The two barrels operate anti-synchronously. The central region between the two barrels contains a high concentration of disordered protein chains, the role of which was thus far unclear. In this work we report a combination of atomistic and coarse-grained simulations that probe the structure and dynamics of the equatorial region of the GroEL/GroES chaperonin complex. Surprisingly, our simulations show that the equatorial region provides a translocation channel that will block the passage of folded proteins but allows the passage of secondary units with the diameter of an alpha-helix. We compute the free-energy barrier that has to be overcome during translocation and find that it can easily be crossed under the influence of thermal fluctuations. Hence, strongly non-native proteins can be squeezed like toothpaste from one barrel to the next where they will refold. Proteins that are already fairly close to the native state will not translocate but can refold in the chamber where they were trapped. Several experimental results are compatible with this scenario, and in the case of the experiments of Martin and Hartl, intra chaperonin translocation could explain why under physiological crowding conditions the chaperonin does not release the substrate protein