'Lactobacillus fermentum' 3872 as a potential tool for combatting 'Campylobacter jejuni' infections

Due to the global spread of multidrug resistant pathogenic bacteria, alternative approaches in combating infectious diseases are required. One such approach is the use of probiotics. Lactobacillus fermentum 3872 is a promising probiotic bacterium producing a range of antimicrobial compounds, such as hydrogen peroxide and lactic acid. In addition, previous studies involving genome sequencing and analysis of L. fermentum 3872 allowed the identification of a gene encoding a cell surface protein referred to as collagen binding protein (CBP) (not found in other strains of the species, according to the GenBank database), consisting of a C-terminal cell wall anchor domain (LPXT), multiple repeats of ‘B domains' that form stalks presenting an “A domain” required for adhesion. In this study, we found that the CBP of L. fermentum 3872 binds to collagen I present on the surface of the epithelial cells lining the gastrointestinal tract. Moreover, we found that this host receptor is also used for attachment by the major gastrointestinal pathogen, Campylobacter jejuni. Furthermore, we identified an adhesin involved in such interaction and demonstrated that both L. fermentum 3872 and its CBP can inhibit binding of this pathogen to collagen I. Combined with the observation that C. jejuni growth is affected in the acidic environment produced by L. fermentum 3872, the finding provides a good basis for further investigation of this strain as a potential tool for fighting Campylobacter infections

Peripheries and praxis: the effect of rubric co-construction on student perceptions of their learning

The construction of assessment rubrics is often educator-centric as lecturers work in isolation to compose grading tools. While there is a pedagogical goal to construct instruments that align with learning outcomes and guide the assessment of students’ learning, students are often at the periphery of this process. In many higher education institutions, students are accustomed to receiving assessment feedback but they are not, typically, active participants in the feedback cycle. Increasingly, institutions are seeking evidence of greater student engagement in their tertiary learning experience. Accordingly, academics seek to innovate practice and enhance curricula by creating more opportunities for student involvement, thus creating a shared understanding of it and associated assessment tasks. Responding to a gap in rubric construction practice, this paper discusses an Office for Learning and Teaching Innovation and Development Grant research project where students moved from being rubric users to being central participants in collaborative design. Drawing on data collected from a team of rubric co-constructors from one Sydney university campus – first year students and an academic in a creative non-fiction writing subject – we set out to answer the following question: What effect does the co-construction and use of rubrics have on students’ perceptions of their learning

Sensory adaptation in naive peripheral CD4 T cells

T cell receptor interactions with peptide/major histocompatibility complex (pMHC) ligands control the selection of T cells in the thymus as well as their homeostasis in peripheral lymphoid organs. Here we show that pMHC contact modulates the expression of CD5 by naive CD4 T cells in a process that requires the continued expression of p56(lck). Reduced CD5 levels in T cells deprived of pMHC contact are predictive of elevated Ca(2)+ responses to subsequent TCR engagement by anti-CD3 or nominal antigen. Adaptation to peripheral pMHC contact may be important for regulating naive CD4 T cell responsiveness

True mid-infrared Pr3+ absorption cross-section in a selenide-chalcogenide host-glass

The mid-infrared (MIR) spans the 3-25 m wavelength range. Rare-earth-ion doped selenide-chalcogenide glasses are being developed for direct-emission MIR fibre lasers. The true Pr3+ absorption cross-section in the 3.5-6 µm wavelength region of a Pr3+-doped (500 ppmw of Pr3+ i.e. 9.47 x 1019 Pr3+ ions cm-3) GeAsGaSe host-glass is presented, after numerically removing the underlying, extrinsic vibrational absorption due to [H-Se-] contamination of the host-glass

True mid-infrared Pr3+ absorption cross-section in a selenide-chalcogenide host-glass

The mid-infrared (MIR) spans the 3-25 m wavelength range. Rare-earth-ion doped selenide-chalcogenide glasses are being developed for direct-emission MIR fibre lasers. The true Pr3+ absorption cross-section in the 3.5-6 µm wavelength region of a Pr3+-doped (500 ppmw of Pr3+ i.e. 9.47 x 1019 Pr3+ ions cm-3) GeAsGaSe host-glass is presented, after numerically removing the underlying, extrinsic vibrational absorption due to [H-Se-] contamination of the host-glass

Promising emission behavior in Pr 3+ /In selenide-chalcogenide-glass small-core step index fiber (SIF)

Selenide-chalcogenide glass, small-core, step-index fiber (SIF), core-doped with Pr3+: 9.51 × 1024 ions m−3 (500 ppmw) is fabricated for the first time with indium to help solubilize Pr3+. Core diameters of 20 or 40 μm are confirmed using scanning electron microscopy and near-field imaging; fibre numerical aperture is ∼0.4. Optical loss is ≥ 4.9 dB m−1 across the 3–9 μm mid-infrared (MIR) spectral range. On pumping at 1.55 μm or 2.013 μm, the SIFs give broad MIR emission across 3.5–6 μm assigned to 3H6 → 3H5 and 3H5 → 3H4. The Pr3+ emission-lifetime at 4.7 μm decreases from bulk-glass (10.1 ± 0.3 ms), to intermediately processed fiber (8.10 ± 0.5 ms) to SIF (7.1 ± 0.5 ms) induced by the processing. On end-pumping SIFs at 2.013 μm, the output pump-power and emission intensity at 4.7 μm became sub-linear and super-linear, respectively, suggesting MIR excited-state saturation is occurring

Determining the continuous thermo-optic coefficients of chalcogenide glass thin films in the MIR region using FTIR transmission spectra

A new method (FTIR continuous dn / dT method, n is refractive index and T temperature) for measuring the continuous thermo-optic coefficients of thin transparent films in the mid-infrared (MIR) spectral region is introduced. The technique is based on Fourier transform infrared (FTIR) transmission spectra measured at different temperatures. It is shown that this method can successfully determine the thermo-optic coefficient of chalcogenide glass thin films (of batch compositions Ge20Sb10Se70 at. % (atomic %) and Ge16As24Se15.5Te44.5 at. %) over the wavelength range from 2 to 25 µm. The measurement precision error is less than ±11.5 ppm / ºC over the wavelength range from 6 to 20 µm. The precision is much better than that provided by the prism minimum deviation method or an improved Swanepoel method

Invest Ophthalmol Vis Sci

Purpose: To investigate the relationship of growth in drusen size with genetic susceptibility and adherence to the alternate Mediterranean diet. Methods: Participants in this analysis had complete ocular, genetic, and dietary data with mean follow-up time of 10.2 years in the Age-Related Eye Disease database. Maximal drusen size was graded on an ordinal scale and two-step progression was determined. A genetic risk score using variants associated with advanced AMD and derived from a stepwise regression model yielded 11 variants in 8 genes. Adherence to the alternate Mediterranean diet was assessed using a nine-component score based on intake of vegetables, fruits, legumes, whole cereals, fish, meat, nuts, alcohol, and monounsaturated-to-saturated fatty acids ratio. Multivariate Cox proportional hazards models were used. Results: Among 3023 eligible eyes, 19% had drusen growth. In the stepwise selection, common and rare risk alleles for CFH Y402H, CFH rs1410996, CFH R1210C, C3 R102G, C3 K155Q, and ARMS2/HTRA1, as well as VEGF-A, TIMP3, NPLOC4, and HSPH1 variants were significantly associated with 2-step progression in drusen size, and the C2 E318D protective allele conferred decreased risk, adjusting for other covariates. A higher genetic risk score conferred a higher risk (hazard ratio per 1-unit increase, 2.68; 95% confidence interval, 2.23–3.23; P < 0.001), and a medium/high adherence to alternate Mediterranean diet score (4–9) tended to lower risk (hazard ratio, 0.83; 95% confidence interval, 0.68–0.99; P = 0.049), adjusting for all covariates. Conclusions: Genetic susceptibility was independently related to drusen growth. A Mediterranean-style diet with healthful nutrient-rich foods (fruits, vegetables, legumes and fish), may reduce enlargement of drusen, the hallmark of AMD