DFT computational investigation of tuning the electron donating ability in metal-free organic dyes featuring a thienylethynyl spacer for dye sensitized solar cells

The recent improvements in metal-free organic dye-sensitized solar cells (DSSCs) have been attributed to the ability to tune the optical and electronic properties through various structural modifications. Within the donor-π-conjugated spacer-acceptor (D-π-A) architecture, the electron-donating and accepting strengths have been proven to be major control variables for increasing the energy conversion efficiency. In the present study, a series of metal-free organic D-π-A dyes for DSSCs were designed and investigated. In particular, the electron donating strength was modulated by adding electron donating groups to the donor side. The HOMO energy increased with a gradual increase in donor strength which was verified by an investigation of the bond distances between the nitrogen and carbon atom of phenyl ring connected with π-conjugated spacer. The net electron transfer from the donor to acceptor, calculated from natural bond orbital (NBO) analysis, also showed quantitative correlation with the bond distances. Finally, the absorption peak shifted to a longer wavelength with the increase of donor strength as well as π-conjugated spacer. Detailed analysis of the results supported that all properties investigated has a strong correlation with the bond distance between the nitrogen and the carbon atom in the phenyl ring attached to the π-conjugated spacer. Based on this apparent correlation, this bond distance from ground-state DFT calculations may be used as a descriptor for the high throughput screening of DSSC dyes instead of using computationally expensive TDDFT calculations. © 2016 Elsevier B.V1661sciescopu

Ultrasound biomicroscopic study of the effects of topical latanoprost on the anterior segment and ciliary body thickness in dogs

Objective The goal of this study was to evaluate the effects of topical latanoprost on the anterior segment and ciliary body using ultrasound biomicroscopy (UBM) in dogs. Animals studied This study included six eyes of six clinically normal beagles. Procedures UBM scans were performed on six sedated dogs before and 2 h after topical latanoprost instillation. From the next day on, latanoprost was topically applied twice daily for 7 days. After 1 week of instillation, the UBM scans were repeated. The ciliary body thickness (CBT) and the anterior segment parameters, including the iridocorneal angle (ICA), the width of the ciliary cleft (CC) entry, the length of the CC, and the width of the mid-CC, were measured. Results The topical latanoprost decreased the ICA and CC entry width and increased the mid-CC width without any significant alterations in the CC length. There were time-dependent alterations in the CBT: a reduction in the CBT after 2 h of instillation and rebound thickening after 1 week of instillation. Conclusions The topical latanoprost widened the ciliary cleft despite the narrowing of the ICA and CC entry. Time-dependent alterations in the CBT were demonstrated by the UBM and might be a reflection of the mechanism of the uveoscleral outflow enhancement induced by the topical latanoprost.N

Increased HOXC6 mRNA expression is a novel biomarker of gastric cancer.

In this study, we aimed to investigate the molecular biomarkers that are pivotal for the development and progression of gastric cancer (GC). We analyzed clinical specimens using RNA sequencing to identify the target genes. We found that the expression of HOXC6 mRNA was upregulated with the progression of cancer, which was validated by quantitative real time PCR and RNA in-situ hybridization. To compare the protein expression of HOXC6, we evaluated GC and normal gastric tissue samples using western blot analysis and immunohistochemistry. We detected significantly higher levels of HOXC6 in the GC tissues than in the normal controls at both mRNA and protein levels. The expression levels of HOXC6 mRNA in patients with advanced gastric cancer (AGC) were significantly higher than those in patients with early gastric cancer (EGC). Kaplan-Meier curves showed that high expression of HOXC6 mRNA is significantly associated with poor clinical prognosis. Our findings suggest that HOXC6 mRNA may be a novel biomarker and can be potentially valuable in predicting the prognosis of GC patients. Especially, HOXC6 mRNA in-situ hybridization may be a diagnostic tool for predicting prognosis of individual GC patients

Novel Herbal Therapeutic YH23537 Improves Clinical Parameters in Ligature-Induced Periodontal Disease Model in Beagle Dogs

Currently, available medicine does not satisfy the clinical unmet needs of periodontal disease. Therefore, novel drugs with improved efficacy profiles are needed. We previously demonstrated that YH14642, water extracts of Notoginseng Radix and Rehmanniae Radix Preparata, improved probing depths in double-blind phase II clinical trial. However, it still has hurdles for commercialization due to the low efficiency of active compound extraction. To resolve this issue, we developed YH23537 through process optimization to extract active compounds efficiently while still achieving the chemical profile of YH14642. In this study, we investigated the therapeutic effects of YH23537 compared with YH14642 using a canine model of ligature-induced periodontitis. Human gingival fibroblast (hGF) cells were treated with various concentrations of YH23537 or YH14642 with lipopolysaccharide (LPS) for 24 hr. IL-6 and IL-8 levels in the conditioned media were determined using Luminex. Sixteen 3-year-old male beagle dogs had their teeth scaled and polished using a piezo-type ultrasonic scaler under general anesthesia and brushed once daily for the following 2 weeks. Two weeks after the scaling procedure, the left upper second premolar (PM2), third premolar (PM3), and fourth premolar (PM4) as well as the left lower PM3, PM4, and first molar (M1) were ligated with silk-wire twisted ligatures. The dogs were fed with soft moistened food to induce periodontitis for 8 weeks, and the ligatures were then removed. YH23537 and YH14642 were administered for 4 weeks, and clinical periodontal parameters such as plaque index (PI), gingival index (GI), probing depth (PD), clinical attachment level (CAL), and bleeding on probing (BoP) were determined before and 1, 2, 3, and 4 weeks after treatment. YH23537 inhibited IL-6 and IL-8 secretion in a dose-dependent manner in hGF cells stimulated with LPS. The IC50 values for YH23537 were 43 and 54 μg/ml for IL-6 and IL-8, respectively, while the values for YH14642 were 104 and 117 μg/ml, respectively. In the animal study, clinical parameters including GI, PD, CAL, and BoP were significantly increased after 8 weeks of ligature-induced periodontitis. The YH23537 300 and YH23537 900 mg groups had significant improvements in CAL from 1 to 4 weeks after treatment in comparison to the placebo group. GR values in the YH23537 900 mg group were decreased throughout the treatment period. GI values were also reduced significantly after 4-week treatment with 300 and 900 mg of YH23537. YH23537 at 300 mg doses showed comparable efficacy for CAL and GR with 1,000 mg of YH14642. YH23537 showed therapeutic efficacy against periodontitis in dogs, mediated by anti-inflammatory effects. These findings indicate that YH23537 has the potential for further development as a new drug for patients suffering from periodontal disease