The effect of polyphenols in post stroke adults: A systematic review of randomised controlled trials.

BACKGROUND: After a stroke, survivors are often left with significant disabilities and are at a greater risk of recurrent strokes. It is vital stroke survivors receive effective treatments to assist with rehabilitation and reduce risk factors for secondary stroke. Observational and preclinical studies have highlighted the promising role of polyphenols in these regards. METHODS: A systematic review of original research which assessed the role of polyphenols on health outcomes in post stroke adults was conducted. PROQUEST, SCOPUS (Elsevier), MEDLINE (EBSCO), Embase and Cochrane Library databases were searched up to the 29th of October 2021. RESULTS: A total of 9 studies met the full inclusion criteria and were included in this review. Several classes of polyphenols were assessed including hydroxybenzoic acids, stilbenes and flavonoids. Numerous health outcomes were assessed including vascular function, stroke disability, blood pressure, blood glucose and c-reactive protein. The majority of the studies included in this review (n = 8) note improvements in the polyphenol groups for at least one outcome measure. However, small sample sizes, short trial length and reporting bias prevent firm conclusions from being drawn. CONCLUSION: This review provides promising preliminary evidence that polyphenols may be beneficial for post stroke adults, however, more research is required. To ensure reliable methodology and replication of results, future studies should include outcome statistics and effect sizes. Trials with a longer duration and large sample size should also be considered.

Genetic conflicts during meiosis and the evolutionary origins of centromere complexity.

Centromeric DNA evolves rapidly, ranging in size and complexity over several orders of magnitude. Traditional attempts at studying centromeres have left unexplained the causes underlying this complexity and rapid evolution. Instead of directly studying centromeric DNA sequence, our approach has been to study the proteins that epigenetically determine centromere identity. We have discovered that centromeric histones (CenH3s) have evolved under positive selection in multiple lineages, suggesting an involvement in recurrent genetic conflict. Our hypothesis is that 'centromere-drive' is the source of this conflict. Under this model, centromeres compete via microtubule attachments for preferential transmission in female meioses occurring in animals and plants. Since only one of four meiotic products will become the egg, this competition confers a selfish advantage to chromosomes that can make more microtubule attachments, resulting in runaway expansions of centromeric satellites. While beneficial to the 'driving' chromosome, these expansions can have deleterious effects on the fitness of an organism and of the species. CenH3s as well as other heterochromatin proteins have evolved under positive selection to suppress the deleterious consequences of 'centromere-drive' by restoring meiotic parity.

Roles of phosphatidylinositol 3-kinase in interferon-gamma-dependent phosphorylation of STAT1 on serine 727 and activation of gene expression.

STAT1 must be phosphorylated on serine 727 to be fully active in transcription. We show that phosphatidylinositol 3-kinase (PI3K) and its effector kinase Akt play an important role in the serine phosphorylation of STAT1 and in the activation of gene expression in response to interferon-gamma (IFN gamma). IFN gamma activates PI3K as well as Akt in a variety of cell lines. Specific inhibition of PI3K abrogates IFN gamma-induced, but not interleukin-1- or tumor necrosis factor-alpha-induced, phosphorylation of STAT1 on serine and reduces STAT1-dependent transcription and gene expression by approximately 7-fold. Constitutively active forms of PI3K or Akt activate and their dominant-negative derivatives inhibit STAT1-driven transactivation in response to IFN gamma. In addition to PI3K and Akt, JAK1, JAK2, and the tyrosine 440 STAT1 docking residue of IFNGR1 are required for STAT1 to be phosphorylated on serine. Taken together, these results suggest that the following events lead to the activation of STAT1 upon IFN gamma stimulation: 1) PI3K and Akt are activated by the occupied receptor and Tyr-440 is phosphorylated by the activated JAKs; 2) STAT1 docks to Tyr-440; and 3) Tyr-701 is phosphorylated by the JAKs and Ser-727 is phosphorylated by a kinase downstream of Akt.

[Standard versus decreasing weight loss. Better tolerance and comfort in hemodialysis]. / Pérdida standard vs. pérdida decreciente. Mejor tolerancia y confort en hemodiálisis.

The usual procedure to eliminate an overweight in hemodialysis consist in eliminating the whole amount of water distributed in an equitable way during the four hours hemodialysis session. This approach has tried to establish in what way the comfort of patients under dialysis improved, varying this loss in a decreasing way from the beginning to the end of the session.