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Photoluminescent molecules and nanomaterials have potential applications as active waveguides, but have often been limited by high optical losses and complex fabrication processes. We explored ligand-protected metal nanoclusters, which can have strong, stable and tunable emission, as waveguides. Two alloy ligand-protected metal nanoclusters, Pt 1 Ag 18 and Au x Ag 19-x (7 ≤ x ≤ 9), were synthesized and structurally determined. Crystals of both nanoclusters exhibit excellent optical waveguide performance, with optical-loss coefficients of 5.26 × 10 −3 and 7.77 × 10 −3 decibels per micrometer, dB μm −1 , which are lower than those demonstrated by most inorganic, organic, and hybrid materials. The crystal packing and molecular orientation of the Pt 1 Ag 18 compound led to an extremely high polarization ratio of 0.91. Aggregation enhanced the quantum yields of Pt 1 Ag 18 and Au x Ag 19-x nanoclusters by 115- and 1.5-fold, respectively. This photonic cluster with low loss and high polarization provides a generalizable and versatile platform for active waveguides and polarizable materials.

PurposeThis study aims to investigate Saccharomyces boulardii CNCM I-745 during Helicobacter pylori eradication in children.MethodsOne hundred ninety-four H. pylori positive children were randomized in two groups. Therapy (omeprazole+clarithromycin+amoxicillin or omeprazole+clarithromycin+metronidazole in case of penicillin allergy) was given to both groups during two weeks. In the treatment group (n: 102) S. boulardii was added to the triple therapy, while the control group (n: 92) only received triple therapy. The incidence, onset, duration and severity of diarrhea and compliance to the eradication treatment were compared. A 13C urea breath test was done 4 weeks after the end of eradication therapy in two groups of 21 patients aged 12 years and older to test the H. pylori eradication rate.ResultsIn the treatment group, diarrhea occurred in 12 cases (11.76%), starting after 6.25±1.24 days, lasting 3.17±1.08 days, and compliance to eradication treatment was 100%. In the control group, diarrhea occurred in 26 cases (28.26%), starting after 4.05±1.11 days, lasting 4.02±0.87 days, and in six cases eradication treatment was stopped prematurely (p<0.05). The 13C urea breath test showed successful H. pylori eradication in 71.4% of the patients in the treatment and in 61.9 % in the control group (not significant).ConclusionS. boulardii has a beneficial effect on the prevention and treatment of diarrhea during H. pylori eradication in children. Although S. boulardii did only slightly increase H. pylori eradication rate, compliance to eradication treatment was improved.

The extensive existing knowledge on bi-directional communication between astrocytes and neurons led us to hypothesize that not only ischemia-preconditioned (IP) astrocytes can protect neurons but also IP neurons protect astrocytes from lethal ischemic injury. Here, we demonstrated for the first time that neurons have a significant role in protecting astrocytes from ischemic injury. The cultured medium from IP neurons (IPcNCM) induced a remarkable reduction in LDH and an increase in cell viability in ischemic astrocytes in vitro. Selective neuronal loss by kainic acid injection induced a significant increase in apoptotic astrocyte numbers in the brain of ischemic rats in vivo. Furthermore, TUNEL analysis, DNA ladder assay, and the measurements of ROS, GSH, pro- and anti-apoptotic factors, anti-oxidant enzymes and signal molecules in vitro and/or in vivo demonstrated that IP neurons protect astrocytes by an EPO-mediated inhibition of pro-apoptotic signals, activation of anti-apoptotic proteins via the P13K/ERK/STAT5 pathways and activation of anti-oxidant proteins via up-regulation of anti-oxidant enzymes. We demonstrated the existence of astro-protection by IP neurons under ischemia and proposed that the bi-directionally protective communications between cells might be a common activity in the brain or peripheral organs under most if not all pathological conditions.