11 research outputs found
Formation of Supermassive Black Holes
Evidence shows that massive black holes reside in most local galaxies.
Studies have also established a number of relations between the MBH mass and
properties of the host galaxy such as bulge mass and velocity dispersion. These
results suggest that central MBHs, while much less massive than the host (~
0.1%), are linked to the evolution of galactic structure. In hierarchical
cosmologies, a single big galaxy today can be traced back to the stage when it
was split up in hundreds of smaller components. Did MBH seeds form with the
same efficiency in small proto-galaxies, or did their formation had to await
the buildup of substantial galaxies with deeper potential wells? I briefly
review here some of the physical processes that are conducive to the evolution
of the massive black hole population. I will discuss black hole formation
processes for `seed' black holes that are likely to place at early cosmic
epochs, and possible observational tests of these scenarios.Comment: To appear in The Astronomy and Astrophysics Review. The final
publication is available at http://www.springerlink.co
Applications of RNA-Seq and Omics Strategies - From Microorganisms to Human Health
The large potential of RNA sequencing and other ""omics"" techniques has contributed to the production of a huge amount of data pursuing to answer many different questions that surround the science's great unknowns. This book presents an overview about powerful and cost-efficient methods for a comprehensive analysis of RNA-Seq data, introducing and revising advanced concepts in data analysis using the most current algorithms. A holistic view about the entire context where transcriptome is inserted is also discussed here encompassing biological areas with remarkable technological advances in the study of systems biology, from microorganisms to precision medicine
Genetic predisposition to higher production of interleukin-6 through -174 G > C polymorphism predicts global cognitive decline in oldest-old with cognitive impairment no dementia
Interleukin 6 (IL-6) is a pro-inflammatory cytokine upregulated in neurodegenerative contexts. The polymorphism IL-6 -174 G > C influences release levels of this cytokine. We aimed to evaluate the influence of IL-6 -174 G > C on global cognitive score of a group with cognitive impairment no dementia in one year of follow-up.Methods The subjects were categorized in two groups: short-term decline in global cognitive score and those with short-term stability or improvement. IL-6 174 G > C information were compared among these groups.Results We observed that individuals with cognitive impairment no dementia with GGlowergenotype were more frequent among global cognitive score non-decliners while carriers of at least one Chigherallele were more frequent in the group with global cognitive score decliners (p = 0.012; RR = 3.095 IC95%= 1.087-8.812).Conclusion These results suggest that the higher expression of IL-6 gene may be an independent risk factor for cognitive decline among individuals with cognitive impairment no dementia
Cerebrospinal fluid biomarkers for the differential diagnosis of Alzheimer’s disease
ABSTRACT Introduction: Several studies have been conducted in order to validate cerebrospinal fluid biomarkers for the diagnosis of Alzheimer’s disease (AD), aiming primarily to facilitate the early diagnosis. Objective: To evaluate CSF biomarkers on patients with probable AD and the applicability of the international references values in this population. Methods: 46 individuals were recruited and classified as probable AD (n = 19), mild cognitive impairment (MCI) (n = 5) and other dementias (n = 22). The cerebrospinal fluid (CSF) biomarkers were measured using the INNOTEST kits for enzyme-linked immunosorbent assay (ELISA). Higher Tau protein values and lower Aβand Innotest Amyloid Tau Index (IATI) values were observed in AD group when compared with MCI; higher levels of Tau and phosphorylated Tau (P-Tau), and lower Aβand IATI values were observed in AD group when compared to patients with other dementias. No biomarker or IATI was able to distinguish between MCI and other dementias. The kappa index between biomarkers and the clinical diagnosis was regular to Tau and IATI, and weak to Aβand P-tau. Conclusion: The cut-off values for each biomarker that showed better combined sensibility and specificity differ from the reference values suggested by the manufacturer. The CSF biomarkers represent important resources that can help with the AD diagnosis, although the results interpretation must be made based on the analysis of the three analytes together. The cut-off values must be established to address the specificities and characteristics of each population
Low mRNA expression of the apoptosis-related genes CASP3, CASP8, and FAS is associated with low induction treatment response in childhood Acute Lymphoblastic Leukemia (ALL)
Defects in apoptosis signaling have been considered to be responsible for treatment failure in many types of cancer, although with controversial results. The objective of the present study was to assess the expression profile of key apoptosis-related genes in terms of clinical and biological variables and of the survival of children with acute lymphoblastic leukemia (ALL). Procedure. The levels of mRNA expression of the apoptosis-related genes CASP3, CASP8, CASP9, FAS, and BCL2 were analyzed by quantitative real-time PCR in consecutive samples from 139 consecutive children with ALL at diagnosis treated by the Brazilian protocol (GBTLI-ALL 99). Gene expression levels and clinical and biological features were compared by the Mann-Whitney test. Event-free survival (EFS) was calculated by Kaplan-Meier plots and log-rank test. A significant correlation was detected between CASP3, CASP8, CASP9, and FAS expression levels (P<0.01) in ALL samples. Higher levels of BCL2 were significantly associated with white blood cell (WBC) count <50,000/mm(3) at diagnosis (P=0.01) and low risk group classification (P=0.008). Lower expression levels of CASP3, CASP8 and FAS gene were associated with a poor response at day 7 according the GBTLI-ALL 99 protocol (P=0.03, P=0.02 and P=0.008, respectively). There was a relationship between FAS gene expression lower than the 75th percentile and lower 5-year EFS (P=0.02). These findings suggest an association between lower expression levels of the pro-apoptotic genes and a poor response to induction therapy at day 7 and prognosis in childhood ALL55110010