Inverted organic photovoltaic device with a new electron transport layer

We demonstrate that there is a new solution-processed electron transport layer, lithium-doped zinc oxide (LZO), with high-performance inverted organic photovoltaic device. The device exhibits a fill factor of 68.58%, an open circuit voltage of 0.86 V, a short-circuit current density of −9.35 cm/mA(2) along with 5.49% power conversion efficiency. In addition, we studied the performance of blend ratio dependence on inverted organic photovoltaics. Our device also demonstrates a long stability shelf life over 4 weeks in air

Optimal application of compressive palatal stents following mesiodens removal in pediatric patients:a Randomized Controlled Trial

There is no scientific evidence supporting the choice of a palatal stent in patients who underwent removal of an impacted supernumerary tooth. We aimed to investigate the effects of palatal stents in patients who underwent supernumerary tooth removal through a palatal approach and to suggest the optimal stent thickness and material. We recruited 144 patients who underwent extraction of a supernumerary tooth between the maxillary anterior teeth. Subjects were assigned to a control group (CG) or one of four compressive palatal stent groups (CPSGs) classified by the thickness and material of the thermoplastic acrylic stent used. Palatal gingival swelling and objective indices (healing, oral hygiene, gingival, and plaque) were evaluated before surgery and on postoperative days (PODs) 3, 7, and 14; pain/discomfort and the Child Oral Health Impact Profile (COHIP) were assessed as subjective indices of the effects of the stent. The CPSGs showed faster healing than did the CG on PODs 7 (P<0.001) and 14 (P=0.043); swelling was measured by 1.64±0.88 mm and 4.52±0.39 mm, respectively. Although swelling was least in the 4-mm hard group (0.92±0.33 mm), the difference compared with that in the 2-mm hard group (1.01±0.18 mm) was not significant (P=0.077). The CPSGs showed better COHIP (P<0.001-0.036) and pain scores (P<0.001) than did the CG on PODs 1-3. Compressive palatal stents reduce discomfort by decreasing pain and alleviating swelling. Although a stent is effective regardless of its thickness and material, 2-mm hard stents maximized such positive effects with minimal discomfort

Nuclear Factor Erythroid-Derived 2-Like 2-Induced Reductive Stress Favors Self-Renewal of Breast Cancer Stem-Like Cells via the FoxO3a-Bmi-1 Axis

Aims: A subpopulation of cancer cells, termed cancer stem cells (CSCs), has stemness properties, such as self-renewal and differentiation, which drive cancer recurrence and tumor resistance. CSCs possess enhanced protection capabilities to maintain reduced intracellular levels of reactive oxygen species (ROS) compared with nonstem-like cancer cells. This study investigated whether reductive stress could regulate self-renewal activity in breast CSCs. Results: We found that manifestation of stemness in breast cancer stem-like cells was associated with an elevated production of reduced glutathione (GSH) maintained by upregulation of glutamate cysteine ligase catalytic subunit (GCLC) and consequently, lowered ROS levels. This was accompanied by upregulation of phospho-AMP-activated protein kinase, FoxO3a, and Bmi-1. Notably, expression of nuclear factor erythroid-derived 2-like 2 (Nrf2) protein was substantially increased in cells undergoing sphere formation. We noticed that expression of Bmi-1 was inhibited after introduction of Nrf2 short interfering RNA into MCF-7 mammosphere cells. Silencing of Nrf2 expression suppressed the xenograft growth of subcutaneously or orthotopically injected human breast cancer cells. Innovation: Association between Nrf2 and self-renewal signaling in CSCs has been reported, but the underlying molecular mechanism remains largely unresolved. This study demonstrates the Nrf2-mediated signaling pathway in maintenance of reductive stress in breast CSCs. Conclusion: Nrf2 overactivation in breast CSCs upregulates GCLC expression and consequently enhances GSH biosynthesis with concurrent reduction in intracellular ROS accumulation, thereby provoking the reductive stress. The consequent upregulation of nuclear FoxO3a and its binding to the promoter of the gene encoding Bmi-1 account for the self-renewal activity of breast cancer stem-like cells and their growth in a xenograft mouse model.

Cytomegalovirus-associated esophageal ulcer in an immunocompetent infant: When should ganciclovir be administered?

Cytomegalovirus (CMV)-associated esophageal ulcer is rare in immunocompetent infants. The presence of inclusion bodies and immunohistochemical staining for CMV in biopsy specimens obtained during esophagogastroduodenoscopy (EGD) indicate that such ulcers occur because of CMV infection. A 7-week-old female infant who experienced frequent vomiting and feeding intolerance was diagnosed with a massive CMV-associated ulcer in the distal esophagus. The ulcer improved after conservative treatment using proton-pump inhibitors; however, ganciclovir was not administered. In a follow-up EGD biopsy specimen, no CMV inclusion bodies were present, and immunohistochemical staining results for this virus were negative. The presence of CMV inclusion bodies indicates active viral replication. If persistent inclusion bodies or positive immunohistochemical staining for CMV is observed in follow-up biopsy specimens, ganciclovir may be used to treat CMV-associated esophageal ulcers

Purification and proteomic identification of putative upstream regulators of polo-like kinase-1 from mitotic cell extracts

AbstractPolo-like kinase-1 (Plk1) is phosphorylated on Thr210 for activation during mitosis. Here, we investigated the question of which kinase(s) is the specific upstream kinase of mitotic Plk1. Upstream kinases of Plk1 were purified from mitotic cell extracts through column chromatography procedures, and identified by mass spectrometry. Candidates for Plk1 kinase included p21-activated kinase, aurora A, and mammalian Ste20-like kinases. Immunoprecipitates of these proteins from mitotic cell extracts phosphorylated Plk1 on Thr210. Even if the activity of Aurora A was blocked with a specific inhibitor, Plk1 phosphorylation still occurred, suggesting that function of Plk1 could be controlled by these kinases for proper mitotic progression, as well as by Aurora A in very late G2 phase for the beginning of mitosis.Structured abstractMINT-7996332: PAK1(uniprotkb:Q13153)physically interacts(MI:0915) withPLK1(uniprotkb:P53350) bypull down(MI:0096)MINT-7996345: PAK3(uniprotkb:O75914)physically interacts(MI:0915) withPLK1(uniprotkb:P53350) bypull down(MI:0096

Three-dimensional nano-foam of few-layer graphene grown by CVD for DSSC

We report a robust and direct route to fabricate a three-dimensional nano-foam of few-layer graphene (3D-NFG) with large area coverage via a chemical vapor deposition (CVD) technique. Pyrolysis of polymer/nickel precursor film under a hydrogen environment, simply prepared by spin-coating, leads to the creation of nano-foam in the film and the reduction process of nickel ions. Carbonized-C and the nickel nano-frame formed from the pyrolysis are used as a solid carbon source and as a catalyst for the growth of graphene under CVD conditions, respectively. We investigate the use of 3D-NFG, with the advantage of large surface area and high conductivity, as an alternative to the Pt counter electrode material in dye sensitized solar cells. The excellent properties of 3D-NFG, fabricated in this simple and direct manner, suggest a great potential for interconnected graphene networks in electronic devices and photocatalytic sensors as well as in energy-related materials.close221

Effects of Berberine and Hwangryunhaedok-Tang on Oral Bioavailability and Pharmacokinetics of Ciprofloxacin in Rats

Hwangryunhaedok-Tang (HR) and berberine-containing single herbs are used to treat bacterial infection and inflammatory diseases in eastern Asia. The combination of berberine-containing herbal medicines and ciprofloxacin can be an excellent antibacterial chemotherapy against multidrug resistance bacteria. To evaluate the pretreatment effect of berberine and HR, vehicle, berberine (25 and 50 mg/kg/day), and HR (1.4 g/kg/day) were daily administered to rats for five consecutive days. On day 6, ciprofloxacin was administered (10 mg/kg, i.v. and 20 mg/kg, p.o.) to rats. To assess cotreatment effect of berberine and ciprofloxacin, berberine (50 mg/kg) and ciprofloxacin (20 mg/kg) were coadministered by single oral gavage. Pharmacokinetic data were estimated by noncompartmental model. Compared with ciprofloxacin alone (control group), coadministration of berberine (50 mg/kg) and ciprofloxacin significantly decreased Cmax of ciprofloxacin (P<0.05). In addition, the pretreatment of berberine (50 mg/kg/day) and HR (1.4 g/kg/day) significantly decreased Cmax and AUC0→∞, compared with control group (P<0.05). The oral bioavailability of ciprofloxacin was reduced by cotreatment of berberine and pretreatment of berberine and HR. Our results suggest that the expression of P-glycoprotein and organic anion and/or organic cation transporters (OAT/OCT) could take a role in reduced oral bioavailability of ciprofloxacin by berberine and HR

Large-scale preparation of active caspase-3 in E. coli by designing its thrombin-activatable precursors

<p>Abstract</p> <p>Background</p> <p>Caspase-3, a principal apoptotic effector that cleaves the majority of cellular substrates, is an important medicinal target for the treatment of cancers and neurodegenerative diseases. Large amounts of the protein are required for drug discovery research. However, previous efforts to express the full-length caspase-3 gene in <it>E. coli </it>have been unsuccessful.</p> <p>Results</p> <p>Overproducers of thrombin-activatable full-length caspase-3 precursors were prepared by engineering the auto-activation sites of caspase-3 precursor into a sequence susceptible to thrombin hydrolysis. The engineered precursors were highly expressed as soluble proteins in <it>E. coli </it>and easily purified by affinity chromatography, to levels of 10–15 mg from 1 L of <it>E. coli </it>culture, and readily activated by thrombin digestion. Kinetic evaluation disclosed that thrombin digestion enhanced catalytic activity (<it>k</it>_cat/<it>K</it>_<it>M</it>) of the precursor proteins by two orders of magnitude.</p> <p>Conclusion</p> <p>A novel method for a large-scale preparation of active caspase-3 was developed by a strategic engineering to lack auto-activation during expression with amino acid sequences susceptible to thrombin, facilitating high-level expression in <it>E. coli</it>. The precursor protein was easily purified and activated through specific cleavage at the engineered sites by thrombin, generating active caspase-3 in high yields.</p

Transparent graphene films with a tunable piezoresistive response

We demonstrate a graphene-coated polymer film as a transparent piezoresistive strain sensor. Strain sensitivity was tuned by controlling the thickness and density of the graphene layer as well as the adhesion force between graphene and the substrate. Chemically reducing the graphene oxide, thereby maximizing its adhesion to the substrate, while minimizing the coating density and thickness resulted in excellent transparency and high gauge factors. The fabrication method presented allows design optimization of transparent, high-performance, and sensitivity-tunable piezoresistive sensors, which can make inroads into such applications as wide-area strain sensors, self-sensing flexible electronics, and intelligent structural health monitoring.close0

Power conversion efficiency enhancement based on the bio-inspired hierarchical antireflection layer in dye sensitized solar cells

We have investigated the effects of the introduction of an antireflection layer consisting of a hierarchically patterned diffraction grating into a conventional TiO2 working electrode on the power conversion efficiency (PCE) of a DSSC. High index-contrast TiO2 nanowires (NWs) were grown in the circular holes of the two-dimensional diffraction grating prepared through the use of a polymer template fabricated via interference lithography (IL) for maximized photon trapping effects in the visible region of light. The larger scale dimension of the polymer template was determined using the beam parameters of the IL and the smaller scale dimension in the structures was controlled by the growth conditions of the TiO2 NWs. Compared with a conventional DSSC, the hybrid nanostructure with an additional antireflection layer demonstrated higher and wider absorption bands of wavelength spectra, leading to an increased PCE due to enhanced light trapping effects achieved by the combination of antireflection and diffraction of the light on the front surface of the devices with minimum loss in the surface area of the hierarchical structure. The excellent performance of the optimized hybrid nanostructure indicates that the nanophotonic effects have strong potential for solar energy conversion, photocatalyst, and photoelectrode applications.close10