Novel migrating mouse neural crest cell assay system utilizing P0-Cre/EGFP fluorescent time-lapse imaging

<p>Abstract</p> <p>Background</p> <p>Neural crest cells (NCCs) are embryonic, multipotent stem cells. Their long-range and precision-guided migration is one of their most striking characteristics. We previously reported that <it>P0-Cre/CAG-CAT-lacZ </it>double-transgenic mice showed significant lacZ expression in tissues derived from NCCs.</p> <p>Results</p> <p>In this study, by embedding a <it>P0-Cre/CAG-CAT-EGFP </it>embryo at E9.5 in collagen gel inside a culture glass slide, we were able to keep the embryo developing <it>ex vivo </it>for more than 24 hours; this development was with enough NCC fluorescent signal intensity to enable single-cell resolution analysis, with the accompanying NCC migration potential intact and with the appropriate NCC response to the extracellular signal maintained. By implantation of beads with absorbed platelet-derived growth factor-AA (PDGF-AA), we demonstrated that PDGF-AA acts as an NCC-attractant in embryos.</p> <p>We also performed assays with NCCs isolated from <it>P0-Cre/CAG-CAT-EGFP </it>embryos on culture plates. The neuromediator 5-hydroxytryptamine (5-HT) has been known to regulate NCC migration. We newly demonstrated that dopamine, in addition to 5-HT, stimulated NCC migration <it>in vitro</it>. Two NCC populations, with different axial levels of origins, showed unique distribution patterns regarding migration velocity and different dose-response patterns to both 5-HT and dopamine.</p> <p>Conclusions</p> <p>Although avian species predominated over the other species in the NCC study, our novel system should enable us to use mice to assay many different aspects of NCCs in embryos or on culture plates, such as migration, division, differentiation, and apoptosis.</p

Економіко-математичне моделювання оптимізації фінансування заходів щодо збереження біорізноманіття (Economic modeling optimization funding for biodiversity)

Удосконалено організаційно-економічний механізм збереження біорізноманіття України відповідно до умов збалансованого розвитку. Обґрунтовано концептуальні положення збереження біорізноманіття, які базуються на соціо-еколого-економічній оцінці функціонування екосистем. Розроблено методологічні підходи до врахування збереження біорізноманіття у національних рахунках держави, що ґрунтуються на визначенні економічної оцінки функціонування природних екосистем. Поглиблено методологію збереження біорізноманіття на основі поєднання і розвитку теорії систем та інституціональної економіки. Розширено механізми застосування інноваційних інструментів збереження біорізноманіття. Розроблено концептуальні підходи маркетингової стратегії розвитку природно-заповідних територій на основі формування їх позитивного іміджу й адаптації до ринкових умов. (The investigation is devoted to the organization-economic mechanism improvement of the biodiversity conservation in Ukraine in relation to the sustainable development conditions. The conceptual principles of the biodiversity that are based on ecological and social and economic assessment of ecosystem functioning were scientifically proved for the first time in this research. The methodological approaches to the biodiversity conservation in the national state accounts were developed and they are based on the new calculations of the economic evaluation of the natural ecosystem functioning. The methodology and tools of the economic mechanism for resolving environmental conflicts at international level are improved. The methodology of the biodiversity conservation which is based on the institutional economics theory and the systems theory was improved. The innovative mechanisms for biodiversity conservation tools were expanded.

Magnifying Colonoscopy Findings for Differential Diagnosis of Sessile Serrated Adenoma/Polyps and Hyperplastic Polyps

Sessile serrated adenoma/polyps (SSA/Ps) are thought to be precursors of colorectal cancers. However, current endoscopic techniques for differentiating SSA/Ps from conventional hyperplastic polyps (HPs) have low diagnostic accuracy. The aim of the present study was to assess the ability of mucosal crypt patterns to distinguish SSA/Ps from HPs. We examined 140 lesions from 93 patients that had been diagnosed histologically as SSA/Ps or HPs at the Showa University Hospital between June 2010 and May 2012. Three experienced colonoscopists reviewed the endoscopic findings of magnifying colonoscopy. Type II open-shape (Type II-O) pit patterns and varicose microvascular vessels (VMVs) were identified according to previously proposed definitions. Although 140 lesions were initially identified for the study, 27 lesions were excluded from analysis because of insufficient endoscopic findings. Thus, endoscopic findings from a total of 113 lesions (68 SSA/Ps and 45 HPs) were evaluated. Of 113 serrated polyps, 51 lesions (44 SSA/Ps and 7 HPs; P<0.01) had Type II-O pit patterns. The inter- and intra-observer agreement for these patterns among three colonoscopists was κ=0.61 (range 0.57–0.65) and κ=0.68 (range 0.52–0.94), respectively. The positive predictive value (PPV), negative predictive value (NPV), sensitivity, and specificity of Type II-O pit patterns for differentiating between SSA/P and HP were 86%, 61%, 65%, and 84%, respectively. In contrast, the PPV, NPV, sensitivity, and specificity of VMVs were 68%, 43%, 37%, and 73%, respectively. The results indicate that Type II-O mucosal crypt patterns may be useful for the differential diagnosis of SSAPs and HPs

Comparison between adhesion properties of adhesive bonding and adhesive-free adhesion for heat-assisted plasma-treated polytetrafluoroethylene (PTFE)

Heating during plasma treatment, known as heat-assisted plasma treatment, has recently reported to positively affect the adhesion properties of polytetrafluoroethylene (PTFE). In the present study, the adhesion properties of adhesive bonding and adhesive-free adhesion were compared for plasma-treated PTFE with different plasma treatment times and with or without heating during the plasma treatment. The relations among adhesion strength, plasma treatment time, radical density ratio, surface morphology, and surface hardness were investigated. No correlation was found between the adhesion strength and the radical density ratio or between the adhesion strength and the oxygen-containing-functional-group ratio. In contrast, correlation was observed between the adhesion strength and the surface hardness. In addition, the heat-assisted plasma treatment time affected the recovery of the weak boundary layer on the PTFE surface. Adhesive-free adhesion was found to require a longer heat-assisted plasma treatment time than adhesive bonding in order to achieve a high adhesion strength such as 1 N/mm

Effect of rubber compounding agent on adhesion strength between rubber and heat-assisted plasma-treated polytetrafluoroethylene (PTFE)

Although heat-assisted plasma treatment enables drastic improvement of the adhesion property of polytetrafluoroethylene (PTFE), plasma-treated PTFE does not strongly adhere to any adherend. To clarify which rubber compounding agents positively affect the adhesion strength of a plasma-treated PTFE/rubber assembly, six types of unvulcanised rubbers were prepared and thermally compressed to a plasma-treated PTFE sheet. Thus, it was found that SiO 2 addition to rubber drastically increased the adhesion strength of a plasma-treated PTFE/rubber assembly and cohesion failure of rubber occurred with large fractions of SiO 2 although no adhesives were used. To confirm the reaction between plasma-treated PTFE and SiO 2 powder, X-ray photoelectron spectroscopy (XPS) measurements were performed for the thermally compressed SiO 2 /PTFE assembly after repeated washing. The XPS results indicated that hydrophilic SiO 2 powder strongly adhered to the plasma-treated PTFE, whereas hydrophobic SiO 2 powder did not adhere to the PTFE. In this paper, a model was proposed for a possible mechanism of strong adhesion of a PTFE/rubber assembly through both hydrogen and covalent bonds between silanol groups of the SiO 2 powder surface in the rubber and hydroxyl or carboxyl groups on the plasma-treated PTFE