Polarization switching in a mid-infrared Er:YAlO3 laser.

We report on a polarization-resolved study of mid-infrared emission properties of Er3+-doped orthorhombic yttrium aluminum perovskite YAlO3 single crystal. For the 4I11/2 → 4I13/2 Er3+ transition, the stimulated emission cross section is 0.20 × 10-20 cm2 at 2919 nm for light polarization E ‖ c. Pumped by an Yb-fiber laser at 976 nm, the 10 at.% Er:YAlO3 laser delivered 1.36 W at 2919 nm with a slope efficiency of 31.4%, very close to the Stokes limit, a laser threshold as low as 33 mW and a linear polarization. Pump-induced polarization switching between E || b and E || c eigen states was observed and explained by excited-state absorption from the terminal laser level.

C-2-Linked Dimeric Strychnine Analogues as Bivalent Ligands Targeting Glycine Receptors.

Strychnine is the prototypic antagonist of glycine receptors, a family of pentameric ligand-gated ion channels. Recent high-resolution structures of homomeric glycine receptors have confirmed the presence of five orthosteric binding sites located in the extracellular subunit interfaces of the receptor complex that are targeted by strychnine. Here, we report the synthesis and extensive pharmacological evaluation of bivalent ligands composed of two strychnine pharmacophores connected by appropriate spacers optimized toward simultaneous binding to two adjacent orthosteric sites of homomeric α1 glycine receptors. In all bivalent ligands, the two strychnine units were linked through C-2 by amide spacers of various lengths ranging from 6 to 69 atoms. Characterization of the compounds in two functional assays and in a radioligand binding assay indicated that compound 11a, with a spacer consisting of 57 atoms, may be capable of bridging the homomeric α1 GlyRs by simultaneous occupation of two adjacent strychnine-binding sites. The findings are supported by docking experiments to the crystal structure of the homomeric glycine receptor. Based on its unique binding mode, its relatively high binding affinity and antagonist potency, and its slow binding kinetics, the bivalent strychnine analogue 11a could be a valuable tool to study the functional properties of glycine receptors.

The palliative effect of camel milk on hepatic CYP1A1 gene expression and DNA damage induced by fenpropathrin oral intoxication in male rats.

The present study investigated the alleviating role of camel milk (CM) in the mitigation of fenpropathrin (FNP) type II pyrethroid induced oxidative stress, alterations of hepatic (CYP1A1) mRNA expression pattern, and DNA damage using the alkaline comet assay (SCGE) in male rats. Sixty male Sprague-Dawley rats were separated into six groups (n = 10): 1st control (C), 2nd corn oil (CO), 3rd (CM): gavaged CM 2ml/rat, 4th (FNP): gavaged FNP 7.09 mg/kg body weight (BW), 5th (FNP pro/co-treated): gavaged CM firstly for 15 days, then CM + FNP by the same mentioned doses and route, 6th (FNP + CM co-treated): gavaged FNP firstly followed by CM by the same mentioned doses and route. Rats were orally gavaged three times per week, day after day for 60 days. FNP exposure significantly reduced serum glutathione (GSH) levels, but significantly increased serum levels of superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA), protein carbonyl (PCO), and 8hydroxy2deoxyguanosine (8OH2dG). Additionally, FNP exposure significantly up-regulated the mRNA expression levels of hepatic CYP1A1 and increased the SCGE indices in whole blood, liver, and spleen tissues of exposed male rats. Administration of CM significantly regulated the FNP induced oxidative stress, reduced hepatic CYP1A1 mRNA expression levels and values of comet assay indices particularly in the (CM + FNP pro/co-treated) group compared to the (FNP + CM co-treated) group. In conclusion, our results indicate, for the first time, that FNP retains an in vivo genotoxic potential at a dose of (1/10 LD50) and up-regulated hepatic CYP1A1 mRNA expression in male rats. Additionally, CM supplements may improve the genotoxic outcomes, oxidative stress, and altered CYP1A1 mRNA expression induced by FNP particularly in the pro/concurrent-treatment compared to the concurrent treatment alone.

Procoagulant versus anticoagulant factors in cirrhotic patients.

BACKGROUND AND STUDY AIM: Liver cirrhosis leads to decreased production of clotting factors that are generally all produced in the liver except factor VIII and von Willebrand factor. However, cirrhotic patients are not protected from thrombosis. The present study aimed to assess the procoagulant and anticoagulant factors in cirrhotic patients with and without bleeding and/or thrombotic events. PATIENTS AND METHODS: A total of 102 adult subjects were enroled: 51 cirrhotic patients and 51 healthy controls. After full history taking with special attention given to thromboembolic and haemorrhagic events, platelet count, serum albumin, bilirubin, international normalised ratio (INR), PT, partial thromboplastin time (PTT), hepatitis B surface antigen (HBsAg), hepatitis B core (HBc) antibodies, hepatitis C virus (HCV) antibodies, factor VIII, protein C, Protac-induced coagulation inhibition percentage (PICI%) assay and abdominal ultrasound were performed for patients and controls. Upper gastrointestinal endoscopy was conducted for the patients. RESULTS: Compared with control subjects, factor VIII and factor VIII/protein C were significantly higher, while protein C and PICI% were significantly lower among patients. CONCLUSION: Patients with liver cirrhosis may have a tendency for bleeding or thrombosis according to the balance of coagulant and anticoagulant status. PICI%, the assay that evaluated the functionality of the protein C anticoagulant system, was significantly lower in patients compared to control subjects. Accordingly, low PICI% and high factor VIII/protein C ratio can be taken as an index of hypercoagulability in cirrhotic patients.