Conformational and Optical Characteristics of Unidirectionally Twisted Binaphthyl-Bipyridyl Cyclic Dyads

An axially chiral binaphthyl-bipyridyl cyclic dyad in which the two units are connected by short −CH₂O– linkers was synthesized. Experimental and theoretical analyses indicate that the (<i>R</i>)-binaphthyl unit in the dyad induces (<i>R</i>)-chirality in the bipyridyl unit, both in the solid state and in solution. It is shown that vibrational circular dichroism (VCD) is useful to determine the twisting pattern of 2,2′-bipyridyl compounds. The dyad shows crystallization-induced emission enhancement (CIEE)

Qualitative and quantitative assessment of stress dynamic CT perfusion imaging and coronary artery stenosis.

<p>A: Relationship between the transmural extent of hypoperfusion area and myocardial blood flow. B: Relationship between coronary artery stenosis and myocardial blood flow. Boxes with error bars indicate mean values ± standard error. Myocardial blood flow was significantly decreased as the severity of the transmural extent of the hypoperfusion area (HPA) increased from non-HPA to transmural HPA (<i>P</i> < 0.05). Myocardial blood flow was significantly decreased as the severity of coronary stenosis increased (<i>P</i> < 0.05).</p

ECG gated stress dynamic CT perfusion imaging over 30consecutive heart beats of a 70 year-old man with symptomatic coronary artery disease.

<p>Cardiac short-axis views of the early 5 phases (A, B, C, D, E) are shown, and the phase with peak enhancement (F) demonstrates transient subendocardial hypoperfusion areas (red arrows) in the lateral wall of the left ventricular myocardium. Data acquisition over consecutive heartbeats allowed us to perform a robust qualitative assessment of the myocardium without missing the optimal phase from the true volumetric data without temporal gaps.</p

Qualitative and quantitative assessment of myocardial perfusion.

<p>An asymptomatic patient in his 60’s with coronary artery disease. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0083950#pone-0083950-g004" target="_blank">Figures 4A and 4B</a> show cardiac short-axis views at the apical and the mid-ventricular level, respectively. The corresponding time attenuation curves within the regions of interest at the 2 levels (C and D, respectively) show a slight delay in contrast enhancement (red arrow, C) in subendocardial HPA in the apical region (red arrow, A), indicating lower myocardial blood flow. Catheter coronary angiography reveals moderate (50–70%) stenosis in the distal portion of the left anterior descending artery (red arrow, E) and no stenosis in the right coronary artery (F).</p

A patient in his 50’s with effort angina.

<p>(A and B) Short-axis images of stress dynamic CTP imaging show subendocardial HPA (yellow arrow) in the anterior segments and transmural HPA in the inferoseptal segments (red arrow). (C and D) The corresponding time attenuation curves of them reveal late (yellow arrow) and low (red arrow) contrast enhancement patterns and low myocardial blood flow in the HPAs. (E and F) Catheter coronary angiography reveals severe (90%) stenosis at the second diagonal branch (yellow arrow, F) and total occlusion in the proximal portion of the right coronary artery with collateral artery via the left circumflex artery (red arrow, E).</p

<i>Allovahlkampfia spelaea</i> Causing Keratitis in Humans

<div><p>Background</p><p>Free-living amoebae are present worldwide. They can survive in different environment causing human diseases in some instances. <i>Acanthamoeba</i> sp. is known for causing sight-threatening keratitis in humans. Free-living amoeba keratitis is more common in developing countries. Amoebae of family <i>Vahlkampfiidae</i> are rarely reported to cause such affections. A new genus, <i>Allovahlkampfia spelaea</i> was recently identified from caves with no data about pathogenicity in humans. We tried to identify the causative free-living amoeba in a case of keratitis in an Egyptian patient using morphological and molecular techniques.</p><p>Methods</p><p>Pathogenic amoebae were culture using monoxenic culture system. Identification through morphological features and 18S ribosomal RNA subunit DNA amplification and sequencing was done. Pathogenicity to laboratory rabbits and ability to produce keratitis were assessed experimentally.</p><p>Results</p><p><i>Allovahlkampfia spelaea</i> was identified as a cause of human keratitis. Whole sequence of 18S ribosomal subunit DNA was sequenced and assembled. The Egyptian strain was closely related to SK1 strain isolated in Slovenia. The ability to induce keratitis was confirmed using animal model.</p><p>Conclusions</p><p>This the first time to report <i>Allovahlkampfia spelaea</i> as a human pathogen. Combining both molecular and morphological identification is critical to correctly diagnose amoebae causing keratitis in humans. Use of different pairs of primers and sequencing amplified DNA is needed to prevent misdiagnosis.</p></div

AMPK-Activated Protein Kinase Suppresses Ccr2 Expression by Inhibiting the NF-κB Pathway in RAW264.7 Macrophages

<div><p>C-C chemokine receptor 2 (Ccr2) is a key pro-inflammatory marker of classic (M1) macrophage activation. Although Ccr2 is known to be expressed both constitutively and inductively, the full regulatory mechanism of its expression remains unclear. AMP-activated protein kinase (AMPK) is not only a master regulator of energy homeostasis but also a central regulator of inflammation. In this study, we sought to assess AMPK’s role in regulating RAW264.7 macrophage Ccr2 protein levels in resting (M0) or LPS-induced M1 states. In both M0 and M1 RAW264.7 macrophages, knockdown of the AMPKα1 subunit by siRNA led to increased Ccr2 levels whereas pharmacologic (A769662) activation of AMPK, attenuated LPS-induced increases in Ccr2 expression in an AMPK dependent fashion. The increases in Ccr2 levels by AMPK downregulation were partially reversed by NF-κB inhibition whereas TNF-a inhibition had minimal effects. Our results indicate that AMPK is a negative regulator of Ccr2 expression in RAW264.7 macrophages, and that the mechanism of action of AMPK inhibition of Ccr2 is mediated, in part, through the NF-κB pathway.</p></div

AMPKα1 negatively regulates Ccr2 expression in the M0 and the LPS-stimulated M1 macrophages.

<p>A: Reduced AMPKα1 protein levels in macrophages treated with AMPKα1 siRNA RAW264.7 were confirmed by Western blotting of whole cell lysates. β-actin was probed as an internal control. B: Whole cell lysates of RAW264.7 macrophages treated with either control or AMPKα1 siRNA were examined by Western blotting to confirm compensation by AMPKα2. Tissue lysates prepared from mouse retina were used as a positive control for expression of AMPKα2 protein. β-actin was probed as an internal control. C: Ccr2 expression on RAW264.7 macrophages was analyzed by flow cytometry. RAW264.7 macrophages were stimulated with 10–1000 ng/ml of LPS for 12 h. D: Flow cytometry analysis of Ccr2 expression on RAW264.7 macrophages treated with either control or AMPKα1 siRNA. RAW264.7 macrophages were stimulated with 100 ng/ml of LPS for 12 h to induce the M1 state. n = 3. ***, <i>p <</i> 0.001.</p

Morphological characters of trophozoite and cyst.

<p>(A) Trophozoite showing unidirectional movement (arrows) and cyst aggregating to each other (arrow head) (inverted microscope using x20 objective lens). (B) Cysts in 10 days old culture (inverted microscope using x20 objective lens). (C) Trophozoite showing filopodia (arrow) (oil immersion x100 objective lens). (D) Cysts with perinuclear clear ring (x40 objective lens)</p

Pharmacological activation of AMPK counter-regulates Ccr2 expression in the LPS-stimulated M1 macrophages.

<p>A: RAW264.7 macrophages treated with either control or AMPKα1 siRNA were additionally treated with 25–100 μM of the AMPK activator, A769662. The phosphorylation of AMPKα (p-AMPKα) after A769662 treatment was examined by Western blotting. β-actin was probed as an internal control. B: RAW264.7 macrophages were pretreated with 25–100 μM A769662 for 2 h, followed by co-treatment with 100 ng/ml of LPS and each different concentration of A769662 for 12 h. Dimethyl sulfoxide (DMSO) was used as a control. Ccr2 expression was analyzed by flow cytometry. C: RAW264.7 macrophages treated with either control or AMPKα1 siRNA were pretreated with 50 μM A769662 for 2 h, followed by co-treatment with 100 ng/ml of LPS and 50 μM A769662 for 12 h. DMSO was used as a control. Ccr2 expression was analyzed by flow cytometry. n = 3. *, <i>p <</i> 0.05; ***, <i>p <</i> 0.001.</p