Biomechanical Considerations of Patching Material for Posterior Scleral Reinforcement Surgery.

Purpose: To characterize biomechanical properties of genipin-crosslinked human dura mater as reinforcing material for posterior scleral reinforcement (PSR) and to compare it with crosslinked human sclera. Methods: Donor dura mater and sclera were crosslinked in the same optimized genipin solution. Resistance to enzyme degradation for both materials were investigated by exposing the materials to accelerated enzyme degrading. Elastic modulus and tensile strength were measured by biomechanics testing equipment. Crosslinked human dura mater was used as reinforcing patch in PSR on 57 adult pathologic myopic eyes. The patients were followed up for an average 3 years. The main outcome was eye globe axial length change and safety profile of the reinforcing material. Results: Crosslinked dura mater demonstrated similar percentage weight loss to crosslinked sclera when exposed to enzymatic solution. Dura mater has higher density than sclera. The retaining elastic modulus after enzyme exposure was 72.02 MPa for crosslinked dura mater while 53.88 MPa for crosslinked sclera, 34% greater for crosslinked dura mater, P = 0.0186). At the end of 3 years follow-up, the mean globe axis of the surgery eyes was reduced by 1.29 mm (from 30.81 to 29.51 mm, P < 0.0001, paired t-test). Visual acuity (BCVA logMar) improved by 0.10 logMar unit which is an improvement of five letters (P = 0.0184, paired t-test). No material specific complication was noted. Conclusion: Crosslinked human dura mater may be superior to crosslinked human sclera as reinforcing material for PSR to manage progression of high myopia. This material was well tolerated on human eye.

Bioinspired Synthesis of Ce1-x O2:x%Cu2+ Nanobelts for CO Oxidation and Organic Dye Degradation.

Ce1-x O2:x%Cu2+ nanobelts were bioinspired, designed, and fabricated using commercial filter papers as scaffolds by adding Cu(NO3)2 in the original sol solution of CeO2 nanobelts, which display excellent catalyst properties for CO oxidation and photocatalytic activity for organic dyes. Compared with pure CeO2, CuO belts were synthesized using the same method and the corresponding Ce0.5O2:50%Cu2+ bulk materials were synthesized without filter paper as scaffolds; the synthesized Ce1-x O2:x%Cu2+ nanobelts, especially Ce0.5O2:50%Cu2+ nanobelts, can decrease the reaction temperature of CO to CO2 at 100 °C with the conversion rate of 100%, much lower than the formerly reported kinds of Ce1-x O2:x%Cu2+ catalysts. Meanwhile, the synthesized Ce1-x O2:x%Cu2+ nanobelts also display better photocatalytic activity for organic dyes. All of these results provide useful information for the potential applications of the synthesized Ce1-x O2:x%Cu2+ nanobelts in catalyst fields.

Upconversion nanotubes with tunable fluorescence properties based on Gd2O2S:Ln3+ (Ln3+ = Yb3+, Er3+) and derivatives for photodynamic therapy.

In this study, Gd2O2S:Ln3+ (Ln3+ = Yb3+, Er3+) upconversion nanotubes (UCNTs) were synthesised by using Gd(OH)3:Ln3+ (Ln3+ = Yb3+, Er3+) nanotubes as the template. The luminescent and biological properties of Gd2O2S:Ln3+ (Ln3+ = Yb3+, Er3+) UCNTs, along with photodynamic therapy (PDT) applications of the Gd2O2S:8%Yb3+,2%Er3+ UCNT-Ce6 (chlorin e6) nanocomposites, were systematically studied. The resultant UCNTs showed excellent biocompatibility with human retinal pigment cells (ARPE-19) even after a prolonged incubation time of 72 h, and could be used as luminescent probes. Microscopic imaging revealed that the UCNTs existed mainly in cytoplasm. PDT studies on the Gd2O2S:8%Yb3+,2%Er3+ UCNT-Ce6 nanocomposites indicate that the growth of the tumour (cell) could be inhibited dramatically when it was injected (incubated) with Gd2O2S:8%Yb3+,2%Er3+ UCNT-Ce6 nanocomposites under the irradiation of 980 nm laser.

Effects of intravenous infusion of lipopolysaccharide on plasma micromineral, magnesium, and cytokine concentrations and serum cortisol concentrations in lactating goats.

OBJECTIVE: To assess the effects of various doses of lipopolysaccharide (LPS) administered IV on plasma microminerals, magnesium, tumor necrosis factor (TNF)-alpha, and interleukin (IL)-6 concentrations and serum cortisol concentrations in lactating goats. ANIMALS: 6 lactating goats. PROCEDURES: Goats were allotted to 3 LPS-treatment groups: control (0 microg/kg), low LPS (10 microg/kg), and high LPS (50 microg/kg). Rectal temperatures and behaviors of goats were recorded immediately before a 10-minute IV infusion of LPS and at 0.5, 1, 2, 4, 6, 8, and 24 hours after infusion. Blood samples were obtained before IV infusion and at 0.5, 1, 2, 4, 6, 8, and 24 hours after infusion. Plasma zinc, copper, iron, and magnesium concentrations were determined by atomic absorption spectrometry; plasma TNF-alpha and IL-6 concentrations were measured by use of an ELISA; and serum cortisol concentrations were determined by use of a radioimmunoassay. RESULTS: A monophasic fever developed in low-LPS and high-LPS groups. In the low-LPS and high-LPS group, plasma zinc concentrations decreased at 6 hours after infusion; compared with control groups. Plasma iron concentrations were lower at 24 hours after infusion in low-LPS and high-LPS groups than in the control group. Plasma TNF-alpha and IL-6 concentrations were higher in low-LPS and high-LPS groups than in the control group at 1, 2, and 4 hours after infusion. In low-LPS and high-LPS groups, serum cortisol concentrations increased from 0.5 hours onward and peaked at 1 (high-LPS group) and 2 (low-LPS group) hours after infusion. CONCLUSIONS AND CLINICAL RELEVANCE: Following IV infusion of LPS, the immune system is activated, which might affect micromineral homeostatic regulation and, subsequently, the metabolic health of lactating goats.

A hyperspectral X-ray computed tomography system for enhanced material identification.

X-ray computed tomography (CT) can distinguish different materials according to their absorption characteristics. The hyperspectral X-ray CT (HXCT) system proposed in the present work reconstructs each voxel according to its X-ray absorption spectral characteristics. In contrast to a dual-energy or multi-energy CT system, HXCT employs cadmium telluride (CdTe) as the x-ray detector, which provides higher spectral resolution and separate spectral lines according to the material's photon-counter working principle. In this paper, a specimen containing ten different polymer materials randomly arranged was adopted for material identification by HXCT. The filtered back-projection algorithm was applied for image and spectral reconstruction. The first step was to sort the individual material components of the specimen according to their cross-sectional image intensity. The second step was to classify materials with similar intensities according to their reconstructed spectral characteristics. The results demonstrated the feasibility of the proposed material identification process and indicated that the proposed HXCT system has good prospects for a wide range of biomedical and industrial nondestructive testing applications.

Evaluation of Lactobacillus rhamnosus GG using an Escherichia coli K88 model of piglet diarrhoea: Effects on diarrhoea incidence, faecal microflora and immune responses.

Probiotic bacterium Lactobacillus rhamnosus GG (LGG) has been demonstrated to adhere to pig intestinal mucus, and is able to displace and inhibit pathogens, including Escherichia coli (E. coli), in vitro. However, currently there are few data concerning the effects of LGG on piglet health. The objectives of this study were to assess the effectiveness of LGG in reducing the incidence and severity of post-weaning diarrhoea in piglets, and to investigate its mechanisms of action. Eighteen weaned barrows were allocated to nonchallenged control (NCN), challenged control (CCN) and LGG treatment (LGG) groups. Diarrhoea incidence was significantly lower in group LGG than group CCN after E. coli challenge. Faecal coliform bacteria counts were significantly increased, while lactobacilli and bifidobacteria counts were decreased, in group CCN compared with the other groups after challenge. In the jejunum and ileum, secretory immunoglobin A (SIgA) concentrations were significantly higher in group LGG than in group CCN. In group LGG, administration of short-term LGG before E. coli infection attenuated the elevation of serum IL-6 induced by E. coli. Significantly higher concentrations of TNF-alpha were observed in group LGG than NCN and CCN at 6h. IL-1beta concentrations in group NCN were significantly higher than LGG at 6h and higher than CCN at 24h. In conclusion, LGG was effective in ameliorating diarrhoea in post-weaning piglets induced by E. coli K88, possibly via modulation of intestinal microflora, enhancement of intestinal antibody defence, and regulation of production of systemic inflammatory cytokines.