Science at risk? Considering the importance of academic freedom for STEM research production across 17 OECD countries.

Since 2011, a declining trend in academic freedom globally has paralleled a rising tide of neo-nationalism. We use fixed effects models to examine data from the Varieties of Democracy (V-DEM) academic freedom index and bibliometric data for 17 OECD countries across nearly three decades (1981-2007) that precede the recent decline in academic freedom. We find substantial, statistically significant, positive relationships between cross-nationally comparable and longitudinal measures of academic freedom and volume of STEM publications.

A Symbiosis of Access: Proliferating STEM PhD Training in the U.S. from 1920-2010.

Over the course of the 20 century, unprecedented growth in scientific discovery was fueled by broad growth in the number of university-based scientists. During this period the American undergraduate enrollment rate and number of universities with STEM graduate programs each doubled three times and the annual volume of new PhDs doubled six times. This generated the research capacity that allowed the United States to surpass early European-dominated science production and lead for the rest of the century.

Biological or mechanical prostheses for isolated aortic valve replacement in patients aged 50-65 years: the ANDALVALVE study.

Objectives: The decision about whether to use a biological or a mechanical prosthesis for aortic valve replacement remains controversial in patients between 50 and 65 years of age and has yet to be addressed in a Mediterranean population. This research aimed to analyse long-term survival and major morbidity rates (30-day mortality, stroke, any prosthetic reoperation and major bleeding) within this population.

Methods: Our multicentre observational retrospective study included all subjects aged 50-65 years who had a primary isolated aortic valve replacement due to severe aortic stenosis at 7 public hospitals from Andalusia (Spain) between 2000 and 2015.

Octyl gallate markedly promotes anti-amyloidogenic processing of APP through estrogen receptor-mediated ADAM10 activation.

Our previous studies showed that the green tea-derived polyphenolic compound (-)-epigallocatechin-3 gallate (EGCG) reduces amyloid-β (Aβ) production in both neuronal and mouse Alzheimer's disease (AD) models in concert with activation of estrogen receptor-α/phosphatidylinositide 3-kinase/protein kinase B (ERα/PI3K/Akt) signaling and anti-amyloidogenic amyloid precursor protein (APP) α-secretase (a disintegrin and metallopeptidase domain-10, ADAM10) processing. Since the gallate moiety in EGCG may correspond to the 7α position of estrogen, thereby facilitating ER binding, we extensively screened the effect of other gallate containing phenolic compounds on APP anti-amyloidogenic processing. Octyl gallate (OG; 10 µM), drastically decreased Aβ generation, in concert with increased APP α-proteolysis, in murine neuron-like cells transfected with human wild-type APP or "Swedish" mutant APP.

HIV-1 Tat-induced microglial activation and neuronal damage is inhibited via CD45 modulation: A potential new treatment target for HAND.

Microglia become activated in humans subsequent to infection with HIV, and uncontrolled brain inflammation plays a key role in neuronal injury and and cognitive dysfunction during HIV infection. Various studies have shown a deleterious role for the HIV regulatory protein Tat in the development and maintenance of HIV-associated neurocognitive disorders (HAND). One cell surface receptor implicated in inhibiting microglial activation is the protein-tyrosine phosphatase (PTP), CD45.

Autoreactive-Aβ antibodies promote APP β-secretase processing.

Several prior investigations of Alzheimer's disease (AD) patients have indicated naturally occurring autoantibodies against amyloid-β (Aβ) species are produced. Although many studies have focused on the relative concentrations or binding affinities of autoantibodies against Aβ-related proteins in AD and aging, data regarding their functional properties are limited. It is generally believed that these antibodies act to aid in clearance of Aβ.

Mutant presenilin-1 deregulated peripheral immunity exacerbates Alzheimer-like pathology.

Mutations in the presenilin-1 (PS1) gene are independent causes of familial Alzheimer's disease (AD). AD patients have dysregulated immunity, and PS1 mutant mice exhibit abnormal systemic immune responses. To test whether immune function abnormality caused by a mutant human PS1 gene (mhPS1) could modify AD-like pathology, we reconstituted immune systems of AD model mice carrying a mutant human amyloid precursor protein gene (mhAPP; Tg2576 mice) or both mhAPP and mhPS1 genes (PSAPP mice) with allogeneic bone marrow cells.

Green tea epigallocatechin-3-gallate (EGCG) reduces beta-amyloid mediated cognitive impairment and modulates tau pathology in Alzheimer transgenic mice.

We previously reported that intraperitoneal (i.p.) injection (20 mg/kg) of (-)-epigallocatechin-3-gallate (EGCG), the main polyphenolic constituent of green tea, decreased beta-amyloid (Abeta) levels and plaques via promotion of the non-amyloidogenic alpha-secretase proteolytic pathway in "Swedish" mutant amyloid precursor protein overexpressing (APPsw, Tg) mice.

Modulation of neuronal differentiation by CD40 isoforms.

Neuron differentiation is a complex process involving various cell-cell interactions, and multiple signaling pathways. We showed previously that CD40 is expressed and functional on mouse and human neurons. In neurons, ligation of CD40 protects against serum withdrawal-induced injury and plays a role in survival and differentiation.