Increased interactions and engulfment of dendrites by microglia precede Purkinje cell degeneration in a mouse model of Niemann Pick Type-C.

Niemann Pick Type-C disease (NPC) is an inherited lysosomal storage disease (LSD) caused by pathogenic variants in the Npc1 or Npc2 genes that lead to the accumulation of cholesterol and lipids in lysosomes. NPC1 deficiency causes neurodegeneration, dementia and early death. Cerebellar Purkinje cells (PCs) are particularly hypersensitive to NPC1 deficiency and degenerate earlier than other neurons in the brain. Activation of microglia is an important contributor to PCs degeneration in NPC. However, the mechanisms by which activated microglia promote PCs degeneration in NPC are not completely understood. Here, we are demonstrating that in the Npc1nmf164 mouse cerebellum, microglia in the molecular layer (ML) are activated and contacting dendrites at early stages of NPC, when no loss of PCs is detected. During the progression of PCs degeneration in Npc1nmf164 mice, accumulation of phagosomes and autofluorescent material in microglia at the ML coincided with the degeneration of dendrites and PCs. Feeding Npc1nmf164 mice a western diet (WD) increased microglia activation and corresponded with a more extensive degeneration of dendrites but not PC somata. Together our data suggest that microglia contribute to the degeneration of PCs by interacting, engulfing and phagocytosing their dendrites while the cell somata are still present

Increase of Direct C-C Coupling Reaction Yield by Identifying Structural and Electronic Properties of High-Spin Iron Tetra-azamacrocyclic Complexes

Macrocyclic ligands have been explored extensively as scaffolds for transition metal catalysts for oxygen and hydrogen atom transfer reactions. C–C reactions facilitated using earth abundant metals bound to macrocyclic ligands have not been well-understood but could be a green alternative to replacing the current expensive and toxic precious metal systems most commonly used for these processes. Therefore, the yields from direct Suzuki–Miyaura C–C coupling of phenylboronic acid and pyrrole to produce 2-phenylpyrrole facilitated by eight high-spin iron complexes ([Fe3+L1(Cl)2]+, [Fe3+L4(Cl)2]+, [Fe2+L5(Cl)]+, [Fe2+L6(Cl)2], [Fe3+L7(Cl)2]+, [Fe3+L8(Cl)2]+, [Fe2+L9(Cl)]+, and [Fe2+L10(Cl)]+) were compared to identify the effect of structural and electronic properties on catalytic efficiency. Specifically, catalyst complexes were compared to evaluate the effect of five properties on catalyst reaction yields: (1) the coordination requirements of the catalyst, (2) redox half-potential of each complex, (3) topological constraint/rigidity, (4) N atom modification(s) increasing oxidative stability of the complex, and (5) geometric parameters. The need for two labile cis-coordination sites was confirmed based on a 42% decrease in catalytic reaction yield observed when complexes containing pentadentate ligands were used in place of complexes with tetradentate ligands. A strong correlation between iron(III/II) redox potential and catalytic reaction yields was also observed, with [Fe2+L6(Cl)2] providing the highest yield (81%, −405 mV). A Lorentzian fitting of redox potential versus yields predicts that these catalysts can undergo more fine-tuning to further increase yields. Interestingly, the remaining properties explored did not show a direct, strong relationship to catalytic reaction yields. Altogether, these results show that modifications to the ligand scaffold using fundamental concepts of inorganic coordination chemistry can be used to control the catalytic activity of macrocyclic iron complexes by controlling redox chemistry of the iron center. Furthermore, the data provide direction for the design of improved catalysts for this reaction and strategies to understand the impact of a ligand scaffold on catalytic activity of other reactions

The James Webb Space Telescope Mission

Twenty-six years ago a small committee report, building on earlier studies, expounded a compelling and poetic vision for the future of astronomy, calling for an infrared-optimized space telescope with an aperture of at least $4m$. With the support of their governments in the US, Europe, and Canada, 20,000 people realized that vision as the $6.5m$ James Webb Space Telescope. A generation of astronomers will celebrate their accomplishments for the life of the mission, potentially as long as 20 years, and beyond. This report and the scientific discoveries that follow are extended thank-you notes to the 20,000 team members. The telescope is working perfectly, with much better image quality than expected. In this and accompanying papers, we give a brief history, describe the observatory, outline its objectives and current observing program, and discuss the inventions and people who made it possible. We cite detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space Telescope Overview, 29 pages, 4 figure

Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries

Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P < 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely

MG132 attenuates hypoglycemia-induced loss of Nrf2 expression and function.

<p>HCMEC/D3 cells were pretreated with MG132 (5μM) or DMSO (<0.1%) for 3h and exposed to normal or hypoglycemic media containing MG132 or DMSO (<0.1%) for 12h. Endothelial Nrf2 (red) and NQO1 (red) expression and distribution were assessed by IF analysis with images captured at 40X and merged with DAPI (scale: 100μm). Representative images obtained from two independent experiments.</p

Nrf2 critically regulates BBB endothelial structural integrity and function.

<p><b>(A)</b> Nrf2 knock-down efficiency by gene silencing as determined by IF or western blot analyses of Nrf2 (red) and its downstream target, NQO1, in hCMEC/D3 cells transfected with Nrf2-specific or scramble siRNA (n = 3/condition). <b>(B)</b> Effects of Nrf2 silencing on endothelial tight and adherence junction protein expression in hCMEC/D3 monolayers. Respective bands with β-actin as loading control were shown at the bottom of the graphs for each protein (n = 3/condition). <b>(C)</b> Effects of Nrf2 knock-down on TEER and paracellular permeability to the mixture of labeled dextrans (4 and 10kDa) across confluent hCMEC/D3 monolayers cultured on 12 or 24-well Transwell inserts and transfected with scramble or Nrf2 targeting siRNA (n = 5-6/condition). Images were captured at 40X (scale: 100 μm) and merged with DAPI. Data were expressed as mean ± SEM (% of euglycemic scramble control). ***<i>P</i> < 0.01, **<i>P</i> < 0.01, *<i>P</i> < 0.05, vs. control.</p

Siah2, but not Keap1, knock-down inhibits hypoglycemia-induced Nrf2 down-regulation and restores endothelial monolayer integrity.

<p><b>(A)</b> Gene silencing efficiency and specificity determined by IF staining and western blot analysis of Siah2 (red) and Keap1 (green) in hCMEC/D3 cells transfected with gene specific or scramble siRNA. Respective bands with β-actin as loading control were shown at the bottom of the graph (n = 3/condition). <b>(B)</b> IF and western blot analyses of Nrf2 (red) expression/distribution in scramble and Siah2 or Keap1 transfected hCMEC/D3 cells exposed to normal or hypoglycemic conditions (12h) after 72h following transfection (n = 3/condition). <b>(C)</b> Paracellular permeability to labeled dextrans of variable size (4-70kDa) across hCMEC/D3 monolayers transfected with scramble or Siah2-specific siRNA and exposed to 12h normal or hypoglycemia following an interval of 72h after transfection (n = 4-6/condition). (<b>D</b>) Hypoglycemia-induced increase in dextran permeability is independent of the osmotic effects of the media. HCMEC/D3 cells were exposed to equimolar concentrations of glucose with normalglycemic media (L-normal) containing 5.5mM D-glucose + 4.5mM L-glucose and hypoglycemic media (L-Hypo) containing 2.2mM D-glucose + 7.8mM L-glucose (n = 4-5/condition). Images were captured at 40X (scale: 100 μm) and merged with DAPI. Data were expressed as mean ± SEM (% of scramble control). ***<i>P</i> < 0.001, vs. control; ##<i>P</i> < 0.01; #<i>P <</i> 0.05, vs. scramble siRNA-Hypo. Experiments were repeated twice.</p

Hypoglycemia induces progressive down-regulation of Nrf2 expression (protein) and function in hCMEC/D3 cells.

<p><b>(A)</b> IF and western blot analyses of BBB endothelial Nrf2 and its downstream target, NQO1, expression and distribution following 3-24h exposure to normal or hypoglycemic media (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0122358#sec002" target="_blank">Methods</a>; n = 3-4/condition). Respective bands with β-actin as loading control were shown above the graphs for each time point. <b>(B)</b> Effects of hypoglycemia on protein expression/distribution of intracellular regulators of Nrf2, such as Siah2 (3-12h) and Keap1 (12h; <b>B2</b>), as assessed by IF and western blots (n = 3-4/condition). Further, a magnified view of the region represented by yellow box was provided in the inset to demonstrate the cellular localization changes of Siah2 following 12 h exposure to control or hypoglycemic conditions. <b>(C)</b> Real-time qRT-PCR based analysis of mRNA expression of target genes in hCMEC/D3 cells exposed to normal or hypoglycemic media (12h) (n = 4/condition). Data were expressed as mean ± SEM (% normalglycemic control for western blots) or fold change over control (mRNA expression). Images were captured at 40X (scale: 100μm) and merged with DAPI. * <i>P</i> < 0.05 vs. control. Experiments were repeated twice.</p

Forward and reverse primer sequences (5' -3') used in real time qRT-PCR.

<p>Forward and reverse primer sequences (5' -3') used in real time qRT-PCR.</p