Monitoring the intramolecular charge transfer process in the Z907 solar cell sensitizer: a transient Vis and IR spectroscopy and ab initio investigation

We have analyzed the excited state dynamics of the heteroleptic [(NCS)2Ru(bpy-(COOH)2)(bpy-(C6H13)2)] Z907 solar cell sensitizer in solution and when adsorbed onto thin TiO2 films, by combining transient visible and infrared (IR) spectroscopies with ab initio Density Functional Theory (DFT) and Time-Dependent DFT (TDDFT) calculations. Upon excitation with ultra-short pulses in ethanol and dimethyl-sulphoxide solutions, the visible spectra show the appearance of a positive signal around 650 nm, within the instrumental time resolution (<100 fs), which in ethanol undergoes a red-shift in about 20 ps. Measurements in the IR indicate that, upon excitation, both the CN and CO marker bands, associated with the NCS and COOH groups, downshift in frequency, in response to intramolecular ligand + metal (Ru-NCS) to ligand' (bpy-COOH2) charge transfer (LML'CT). Vibrational cooling is observed in both solvents; in ethanol it is overtaken by the hydrogen bond dynamics. On the basis of DFT/TDDFT calculations, explicitly modeling the interaction of the NCS and COOH groups with solvent (ethanol) molecules, we rationalize the observed IR and visible spectral evolution as arising from the change in the hydrogen-bond network, which accompanies the transition to the lowest-energy triplet state. This interpretation provides a consistent explanation of what is also observed in the transient visible spectra. Transient IR measurements repeated for molecules adsorbed on TiO2 and ZrO2 films, allow us to identify the structural changes signaling the dye triplet excited state formation and evidence multiexponential electron injection rates into the semiconductor TiO2 film

Unusual presentation of primary T-cell lymphoblastic lymphoma: Description of two cases

Background: T-cell lymphoblastic lymphoma comprises approximately 85-90% of all lymphoblastic lymphomas. It often arises as a mediastinal mass, and with bone marrow involvement. Presentation at other sites without nodal or mediastinal localization is uncommon. Case report: We describe clinical, histologic, immunohistochemical, and molecular features of two cases of primary T-cell lymphoblastic lymphoma arising respectively in uterine corpus and testis. The tumors were composed by medium to large cells, exhibiting a diffuse pattern of growth but sometimes forming indian files or pseudo-rosettes. The neoplastic cells strongly expressed TdT and T-cell markers in both uterine corpus and testis. However, the testis case also showed aberrant expression of B-cell markers, thus molecular biology was necessary to achieve a final diagnosis. T-cell receptor gene rearrangement analysis identified a T-cell origin. Conclusions: To the best of our knowledge, only one doubtful previous case of primary uterine T-cell lymphoblastic lymphoma and no previous cases of primary testicular T-cell lymphoblastic lymphoma have been reported. Due to the morphology of neoplastic cells, a challenging differential diagnosis with all the tumors belonging to the so-called small round blue cell tumor category is mandatory. In ambiguous lineage cases, molecular biology may represent an adequate tool to confirm diagnosis. Virtual Slides: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/155988097312823

Engineering of Ru(II) dyes for interfacial and light-harvesting optimization

A new Ru(II) dye, Ru(L1)(L2) (NCS)2, L1 = (4-(5-hexylthiophen-2-yl)-4′(4-carboxyl-phenyl 2,2′-bipyridine) and L2 = (4-4′-dicarboxy-2,2′-bipyridine), labelled MC112, based on a dissymmetric bipyridine ligand for improved interfacial and optical properties, was synthesized and used in DSCs, yielding photovoltaic efficiencies of 7.6% under standard AM 1.5 sunlight and an excellent device stability. Increased light harvesting and IPCE maximum were observed with MC112 compared to the prototypical homoleptic N719 dye, due to the functionalized bipyridyne ligand acting as an antenna. In addition, the mixed bipyridyne ligand allowed MC112 binding to TiO2 to occur via three anchoring carboxylic groups, thus exhibiting similar interfacial properties to those of the N719 dye. DFT/TDDFT calculations were performed on the new dye, both in solution and adsorbed on a TiO2 surface model, revealing that the peculiar photovoltaic properties of the MC112 dye are related to its anchoring mode. The new design rule thus allows us to engineer both light-harvesting and interfacial properties in the same dye

Silybin combined with phosphatidylcholine and vitamin E in patients with nonalcoholic fatty liver disease: a randomized controlled trial

The only currently recommended treatment for nonalcoholic fatty liver disease (NAFLD) is lifestyle modification. Preliminary studies of silybin showed beneficial effects on liver function. Realsil (RA) comprises the silybin phytosome complex (silybin plus phosphatidylcholine) coformulated with vitamin E. We report on a multicenter, phase III, double-blind clinical trial to assess RA in patients with histologically documented NAFLD. Patients were randomized 1:1 to RA or placebo (P) orally twice daily for 12 months. Prespecified primary outcomes were improvement over time in clinical condition, normalization of liver enzyme plasma levels, and improvement of ultrasonographic liver steatosis, homeostatic model assessment (HOMA), and quality of life. Secondary outcomes were improvement in liver histologic score and/or decrease in NAFLD score without worsening of fibrosis and plasma changes in cytokines, ferritin, and liver fibrosis markers. We treated 179 patients with NAFLD; 36 were also HCV positive. Forty-one patients were prematurely withdrawn and 138 patients analyzed per protocol (69 per group). Baseline patient characteristics were generally well balanced between groups, except for steatosis, portal infiltration, and fibrosis. Adverse events (AEs) were generally transient and included diarrhea, dysgeusia, and pruritus; no serious AEs were recorded. Patients receiving RA but not P showed significant improvements in liver enzyme plasma levels, HOMA, and liver histology. Body mass index normalized in 15% of RA patients (2.1% with P). HCV-positive patients in the RA but not the P group showed improvements in fibrogenesis markers. This is the first study to systematically assess silybin in NAFLD patients. Treatment with RA but not P for 12 months was associated with improvement in liver enzymes, insulin resistance, and liver histology, without increases in body weight. These findings warrant further investigation