High‐Performance Multilayer Encapsulation for Perovskite Photovoltaics

An encapsulation system comprising of a UV‐curable epoxy, a solution processed polymer interlayer, and a glass cover‐slip, is used to increase the stability of methylammonium lead triiodide (CH₃NH₃PbI₃) perovskite planar inverted architecture photovoltaic (PV) devices. It is found this encapsulation system acts as an efficient barrier to extrinsic degradation processes (ingress of moisture and oxygen), and that the polymer acts as a barrier that protects the PV device from the epoxy before it is fully cured. This results in devices that maintain 80% of their initial power conversion efficiency after 1000 h of AM1.5 irradiation. Such devices are used as a benchmark and are compared with devices having initially enhanced efficiency as a result of a solvent annealing process. It is found that such solvent‐annealed devices undergo enhanced burn‐in and have a reduced long‐term efficiency, a result demonstrating that initially enhanced device efficiency does not necessarily result in long‐term stability.     

A study of some immunological and clinical characteristics of gastritis, gastric ulcer, and duodenal ulcer in three racial groups of the Venezuelan population

Circulating gastric-mucosa antibodies were found more frequently among patients with different forms of chronic gastritis than among a miscellaneous control group and groups that presented prepyloric ulcer or duodenal ulcer. A higher incidence of circulating antibodies and of chronic gastritis lesions among Caucasians and “Mestizos” than among Negroes was also observed. The latter showed a higher tendency to duodenal ulcer and prepyloric ulcer. The high incidence of gastritis and gastric ulcer of the Chinese and the Mestizos support the ethnic relation between these two human groups. Our study favors the hypothesis that genetic and ethnic factors influence, on the one hand, chronic gastritis and gastric ulcer and, on the other hand, duodenal and prepyloric ulcers.     

Host Genetic Background Influences the Response to the Opportunistic Pseudomonas aeruginosa Infection Altering Cell-Mediated Immunity and Bacterial Replication

Pseudomonas aeruginosa is a common cause of healthcare-associated infections including pneumonia, bloodstream, urinary tract, and surgical site infections. The clinical outcome of P. aeruginosa infections may be extremely variable among individuals at risk and patients affected by cystic fibrosis. However, risk factors for P. aeruginosa infection remain largely unknown. To identify and track the host factors influencing P. aeruginosa lung infections, inbred immunocompetent mouse strains were screened in a pneumonia model system. A/J, BALB/cJ, BALB/cAnNCrl, BALB/cByJ, C3H/HeOuJ, C57BL/6J, C57BL/6NCrl, DBA/2J, and 129S2/SvPasCRL mice were infected with P. aeruginosa clinical strain and monitored for body weight and mortality up to seven days. The most deviant survival phenotypes were observed for A/J, 129S2/SvPasCRL and DBA/2J showing high susceptibility while BALB/cAnNCrl and C3H/HeOuJ showing more resistance to P. aeruginosa infection. Next, one of the most susceptible and resistant mouse strains were characterized for their deviant clinical and immunological phenotype by scoring bacterial count, cell-mediated immunity, cytokines and chemokines profile and lung pathology in an early time course. Susceptible A/J mice showed significantly higher bacterial burden, higher cytokines and chemokines levels but lower leukocyte recruitment, particularly neutrophils, when compared to C3H/HeOuJ resistant mice. Pathologic scores showed lower inflammatory severity, reduced intraluminal and interstitial inflammation extent, bronchial and parenchymal involvement and diminished alveolar damage in the lungs of A/J when compared to C3H/HeOuJ. Our findings indicate that during an early phase of infection a prompt inflammatory response in the airways set the conditions for a non-permissive environment to P. aeruginosa replication and lock the spread to other organs. Host gene(s) may have a role in the reduction of cell-mediated immunity playing a critical role in the control of P. aeruginosa infection. These results now provide a basis for mapping genomic regions underlying host susceptibility to P. aeruginosa infection.     

Mode of interaction between beta-lactam antibiotics and the exocellular DD-carboxypeptidase--transpeptidase from Streptomyces R39.

The exocellular DD-carboxypeptidase-transpeptidase of Streptomyces R39 is inhibited by beta-lactam antibiotics according to the same general scheme of reaction as the exocellular DD-carboxypeptidase-transpeptidase of Streptomyces R61. However, the values for the kinetic constants involved in the reaction are very different for the two enzymes and provide an explanation for the observation that the R39 enzyme is more sensitive to beta-lactam antibiotics than the R61 enzyme. Further, particular beta-lactams influence the kinetic constants to different extents depending on the source of the enzyme, so that a physical basis for the spectrum of antibiotic activity against particular enzyme systems is provided.     

Engineering renewable cellulosic thermoplastics

Biopolymers are engineered physically, chemically, genetically or biochemically (i.e. via biotechnological fermentation process) with the purpose to meet specific industry requirements of a wide range of applications. Various technological strategies are reported to create biodegradable plastics with unique physicochemical properties and a predetermined service life. The combination of polymeric material in composites is considered to optimize their mechanical behavior and reliability. Extrusion, a thermomechanical process, is the most widely used technology for producing thermoplastic starch. However, the ease of cellulose accessibility for thermal processing is of increasing economic importance but is complicated by the presence of very strong intermolecular hydrogen bonds in cellulose. Chemical modification is still the common way to get cellulosic thermoplastic products from renewable resources. Therefore, STEP ITN research activities focus on understanding the fundamental chemistry governing polysaccharide transformation and shaping, to utilize this knowledge to introduce thermoplasticity and new functionalities in polymers such as unmodified cellulose.     

The sensitivity and efficacy method of PIK3CA exon 9 E545A as a high diagnostic accuracy in breast cancer

The phosphatidylinositol 3-kinases (PIK3s) are lipid kinases. Mutation in the exon 9 and exon 20 determined as a predictive factor in anti-HER-2 therapy. In some countries, such as Singapore, China, and Peru, PIK3CA exon 9 E545A was reported to produce the highest rate of mutation. In this research, we developed and optimized PIK3CA exon 9 E545A detection methods with intercalating dye SYBR Green I based on the Tm Shift approach by using prepared recombinant plasmid pGEMT-easy PIK3CA exon 9 and PIK3CA exon 9 E545A. Recombinant plasmid was used due to the limited number of samples.

Glycated albumin modified by amadori adducts modulates aortic endothelial cell biology

Increased protein glycation has been mechanistically linked to accelerated vascular pathobiology in diabetes. To test the influence of protein modified by Amadori glucose adducts on vascular cell biology, we examined the effect of glycated albumin on replicative capacity and basement membrane collagen production by aortic endothelial cells in culture. Relative to carbohydrate-free albumin, which supported cell proliferation and Type IV collagen synthesis, glycated albumin significantly inhibited³H-thymidine incorporation and Type IV collagen production. The glycated albumin-induced effects were prevented by monoclonal antibodies (A717) that specifically react with Amadori-modified albumin, but not by IgG that was unreactive with glycated albumin. A717 had no effect on thymidine incorporation or collagen synthesis by cells cultured in the presence of nonglycated albumin. The findings indicate that the interaction of glycated albumin with endothelial cells, which have been shown to display dose-responsive, saturable receptors, limits cell replication and triggers maladaptive biosynthetic programs, which may contribute to degenerative macrovascular disease in diabetes.     

Albumin modified by Amadori glucose adducts activates mesangial cell type IV collagen gene transcription

Increased protein glycation has been mechanistically linked to accelerated vascular pathobiology in diabetes. To test the influence of protein modified by Amadori glucose adducts on vascular cell biology, we examined the effect of glycated albumin on replicative capacity and basement membrane collagen production by aortic endothelial cells in culture. Relative to carbohydrate-free albumin, which supported cell proliferation and Type IV collagen synthesis, glycated albumin significantly inhibited³H-thymidine incorporation and Type IV collagen production. The glycated albumin-induced effects were prevented by monoclonal antibodies (A717) that specifically react with Amadori-modified albumin, but not by IgG that was unreactive with glycated albumin. A717 had no effect on thymidine incorporation or collagen synthesis by cells cultured in the presence of nonglycated albumin. The findings indicate that the interaction of glycated albumin with endothelial cells, which have been shown to display dose-responsive, saturable receptors, limits cell replication and triggers maladaptive biosynthetic programs, which may contribute to degenerative macrovascular disease in diabetes.