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As a new type of topological poly(ethylene glycol) (PEG) analogue, a series of polygonal PEGs with digonal to hexagonal structures were developed. Polygonal PEGs with structures between the digonal and tetragonal types showed molecular-level dispersion in water at 20 °C, whereas the pentagonal and hexagonal PEGs aggregated, which is suggestive of enhanced hydrophobicity by ring expansion. Heating induced conformational changes in the polygonal PEGs and increased their hydrophobicity. Among the polygonal PEGs, only the trigonal and hexagonal PEGs showed a distinct thermal response to form and increase the size of the aggregates, respectively. Given that tetragonal and pentagonal PEGs only marginally responded to heat treatment, the thermal responses are likely due to a topological effect. At low temperatures, the larger polygonal PEGs are more restricted despite the expanded rings. The trigonal PEG showed the largest change in mobility, whereas the tetragonal PEG exhibited the smallest change. Hence, the topology of the polygonal PEGs influences the intramolecular packing and the local dynamics. [ABSTRACT FROM AUTHOR]

Thermoresponsive materials with a lower critical solution temperature (LCST) are receiving growing attention, of which examples of non-polymeric small molecules are limited. Monodisperse oligoethylene glycol amphiphiles that contain aromatic units with a LCST in water have been developed and applied to peptide extraction. Concentration-dependent hysteretic transmittance changes were observed in response to temperature elevation and reduction. Dynamic light scattering measurements and phase contrast microscopy revealed the formation of micrometer-sized aggregates upon heating at a concentration above 5.0 m M; these aggregates self-assembled to form larger aggregates upon cooling before dissolution. The 'interaggregate' interactions are likely to cause the hysteretic behavior. As an application of this thermodriven phase separation, selective extraction of peptide fragments containing high percentages of hydrophobic and aromatic amino acid residues was successfully demonstrated. [ABSTRACT FROM AUTHOR]

Membrane structural organization is an intrinsic property of a cell membrane. Any changes in lipid composition, and/or any stimuli that affect molecular packing induce structural re-organization. It membrane dynamics provide a means by which changes in structure organization can be determined, upon a change in the membrane internal or external environment. Here, we report on the effect of thermo-stress on membranes containing cholesterol liquid crystal (LC) compounds cholesterol benzoate (BENZO) and oxidized cholesterols. We have (1) revealed that lipid vesicles containing this artificial cholesterol derivative (BENZO) is thermo-responsive, and that this thermo-sensitivity is significantly similar to naturally oxy-cholesterols (2) elucidated the mechanism behind the membrane perturbation. Using Langmuir monolayer experiments, we have demonstrated that membrane perturbation was due to an increase in the molecular surface area, (3) discussed the similarities between cholesterol benzoate in the cholesterol LC state and in lipid bilayer membranes. Last, (4) drawing from previously reported findings, our new data on membrane dynamics, and the discussion above, we propose that artificial cholesterol derivatives such as BENZO, open new possibilities for controlled and tailored design using model membrane systems. Examples could include the development of membrane technology and provide a trigger for progress in thermo-tropical liquid crystal engineering. [ABSTRACT FROM AUTHOR]

Abstract: The conformational transition of a plasmid DNA, pGEG.GL3 (12.5kbp, circular), induced by spermine(4+) was studied through the observation of individual DNA by fluorescence microscopy. We deduced the change in the hydrodynamic radius R H from an analysis of the Brownian motion of single DNA molecules. R H decreases in a continuous manner with an increase in spermine(4+), in contrast to the large discrete on/off change for long linear DNA. Just after the transition to the collapsed state, a small number of DNA molecules tend to form an assembly, which disperses in the bulk solution without precipitation. [Copyright &y& Elsevier]

Abstract Background. Development of reflux esophagitis is one of the adverse effects that cause concern in relation to curative treatment of Helicobacter pylori infection. However, recent studies present a rather negative association between curative treatment and development of reflux esophagitis or reflux symptoms. Therefore, this issue has remained controversial. Accordingly, we investigated the long-term adverse effects of H. pylori eradication treatment in special reference to development of reflux symptoms. Patients and Methods. We conducted a case controlled study by mailing structured questionnaires on past (before curative treatment or 3 years previously) and current status. A case was an endoscopically confirmed peptic ulcer patient with confirmed cure of the infection after eradication treatment 3 years previously and a control was one who had not undergone the eradication treatment during the same period. We studied 241 pairs who matched for age, gender, and type of ulcer disease (GU, DU or GDU). Of these pairs, 81.3% were male and the mean age was 52.6 ± 9.6 year (range 23–76). Results. The rates of patients with improved reflux symptoms in the case and control groups were 65.4% and 30.4%, respectively, with the rate being significantly greater in the case group. On the contrary, the rates of those with worsened reflux symptoms were similar (5.1% and 7.6%). Regarding general events, the rate of patients with decreased frequency of hospital visits and of those who regularly used antiacid medications were significantly decreased in the case group. Furthermore, the case group experienced significantly fewer hospital admissions for various diseases in this 3-year period. However, a significantly greater number of case group patients than control subjects gained weight. Conclusion. Reflux symptoms as well as general well-being were significantly improved after cure of H. pylori infection. [ABSTRACT FROM AUTHOR]

A photograph is presented that shows the compression of oligomers with three electron systems that lead to an efficient unidirectional photoexcited energy transfer.

A series of polygonal poly(ethylene glycol) (PEG) analogues with diagonal to hexagonal structures were synthesized. While pentagonal and hexagonal PEGs form aggregates in water at ambient temperature, trigonal and hexagonal PEGs show thermal responses to form or increase aggregates by temperature elevation. Relative hydrophobicity and molecular dynamics of these PEG analogues depend on the topology, likely resulting in their unique self ‐ assembling and thermal properties. More information can be found in the Full Paper by Takahiro Muraoka, Kazushi Kinbara et   al. on page   1028 in Issue 7, 2016 (DOI: 10.1002/asia.201501381). [ABSTRACT FROM AUTHOR]

Amphiphiles Monodisperse oligoethylene glycol amphiphiles bearing aromatic units that exhibit a lower critical solution temperature (LCST) in water have been developed by Takahiro Muraoka, Kazushi Kinbara et   al. In their Full Paper on page 2778   ff., they report their observation of concentration ‐ dependent hysteretic transmittance changes of the amphiphiles in response to temperature elevation and reduction. Dynamic light scattering measurements and phase contrast microscopy displayed the formation of micrometer ‐ size aggregates by heating at concentrations above 5.0   mM. These aggregates self ‐ assemble to form larger aggregates upon cooling before dissolution. [ABSTRACT FROM AUTHOR]

Abstract:We prospectively examined the effect of leukocytapheresis (LA) on the maintenance of remission in 7 patients with ulcerative colitis (UC) who were initially refractory to corticosteroid therapy (steroid resistant or steroid dependent). The patients with refractory UC had been in remission due to LA (induction LA) in combination with the steroid therapy. They were then treated with LA once or twice a month for the purpose of maintaining remission (maintenance LA). The maintenance LA was performed by either a centrifuge method in 5 patients or a polyester adsorbent column method in 2 patients. Steroid dosage was gradually tapered as little as possible without recurrence based on clinical and/or colonoscopical judgments. Four patients were maintained in remission without steroids over 12 months. Recurrence was observed in 3 patients at 3, 3, and 6 months after the beginning of the maintenance LA, respectively. Two of the 3 patients were again conducted to remission by the second induction LA and maintained in remission by the second maintenance LA. Two patients finally underwent total colectomy because of recurrence of UC in a severe form. It is concluded that the maintenance LA therapy might be effective in some patients with steroid dependent or resistant UC for the maintenance of remission without steroids. [ABSTRACT FROM AUTHOR]