TRIENNIAL GROWTH AND DEVELOPMENT SYMPOSIUM: Intramuscular fat deposition in ruminants and pigs: A transcriptomics perspective

The genomics era has led to an explosion in the study of gene expression in production animals. Intramuscular fat (IMF) content (both high and low) and composition are major quality attributes of meat, and more than 90 transcriptomic studies of IMF deposition have been undertaken in the ruminants and pigs since 2001, with the majority since 2008. The studies have implicated many genes involved in the control of adipogenesis, lipogenesis, and deposition of IMF, but there is relatively little consistency between the different studies. However, the genes encoding the synthesis enzymes acetyl-CoA carboxylase α, fatty acid synthase, and stearoyl-CoA desaturase; the fatty acid binding protein 4; the potential signaling protein thyroid hormone responsive; and the regulators C/EBPα, PPARγ, and sterol regulatory element binding transcription factor 1 are supported by 5 or more of the 90 studies. By combining the results of all the studies, complete pathways for long-chain fatty acid (LCFA) and triacylglyceride (TAG) synthesis are identified, as are a number of genes encoding proteins probably associated with the storage of TAG and genes encoding a number of known and potential adipokines. In contrast, support for the association of lipolytic pathways with IMF percentage is less strong. Differences in experimental design-in particular, the age of the animals, the rate of IMF deposition at sampling, the past nutritional history of the animals used, and the complexities of using a tissue with mixed cell types-have contributed to the differences in results and interpretation. Biomarkers predictive of future IMF percentage, facilitating reaching optimal IMF content at slaughter, may have industry utility, but to be useful in animal biopsy and postslaughter samples, where multiple cell types are present, genes must be carefully chosen to ensure that they are informative about the expected processes. Despite these problems, candidate biomarkers for estimation of de novo intramuscular adipocyte LCFA synthesis, LCFA uptake rate by intramuscular adipocytes, and IMF deposition rate have been identified and examples of their utility have been published. However, further work is required to demonstrate how best to apply the assays for the benefit of the relevant livestock production industries.

[A comparison of dosimetric variance for external-beam partial breast irradiation using three-dimensional and four-dimensional computed tomography]

Objective: To investigate the potential dosimetric benefits of four-dimensional computed tomography (4DCT) compared to three-dimensional CT (3DCT) in the planning of radiotherapy for external-beam partial breast irradiation (EB-PBI). Methods: Three-DCT and 4DCT scan sets were acquired for 20 patients who underwent EB-PBI. For each patient a conventional 3D conformal plan (3D-CRT) was generated based on end-inhalation phase (EI). The treatment plan based on the 4DCT EI phase images was copied and applied to the end-exhalation phase (EE) and 3DCT images (defined as EB-PBI(EI), EB-PBI(EE), EB-PBI(3D), respectively). Results: The median volumes of the tumour bed based on 3DCT, EI and EE were 20.99 cm(3,) 19.28 cm(3,) and 18.78 cm(3,) respectively. The tumour bed volume based on 3DCT was significantly greater than that of EI and EE volumes (P<0.05). The planning target volumes (PTV) coverage of EB-PBI(3D), EB-PBI(EI) and EB-PBI(EE) were 96.85%, 97.51%, 97.03%, respectively. The planning target volume (PTV) coverage of EB-PBI(3D) was significantly less than that of EB-PBI(EI) and EB-PBI(EE) (P<0.05). The median homogeneity indexs (HI) based on 3DCT, EI and EE were 0.13, 0.13, 0.13, respectively. The median conformal indexs (CI) based on 3DCT, EI and EE were 0.68, 0.69, 0.68, respectively. The median mean doses (D(mean)) based on 3DCT, EI and EE were 36.20 Gy, 36.20 Gy, 36.22 Gy, respectively. However there were no significant differences in the homogeneity index, conformity index and the mean dose of PTV between the three treatment plans (P>0.05). The EB-PBI(3D) plan resulted in the largest organs at risk dose (P<0.05). Conclusion: There was a significant benefit when using 4DCT to plan 3D-CRT for EB-PBI with regard to reduced non-target organ exposure, and might result in poor dose coverage when the PTV is determined using 3DCT.

Measurement of the Neutrino Mixing Angle θ_{23} in NOvA

This Letter reports new results on muon neutrino disappearance from NOvA, using a 14 kton detector equivalent exposure of 6.05×10^{20} protons on target from the NuMI beam at the Fermi National Accelerator Laboratory. The measurement probes the muon-tau symmetry hypothesis that requires maximal θ_{23} mixing (θ_{23}=π/4). Assuming the normal mass hierarchy, we find Δm_{32}^{2}=(2.67±0.11)×10^{-3}  eV^{2} and sin^{2}θ_{23} at the two statistically degenerate values 0.404_{-0.022}^{+0.030} and 0.624_{-0.030}^{+0.022}, both at the 68% confidence level. Our data disfavor the maximal mixing scenario with 2.6σ significance.

The determination and application of (87) Sr/(86) Sr ratio in verifying geographical origin of wheat

As ⁸⁷ Sr/⁸⁶ Sr ratio plays a significant role in authenticating the geographical origin of foodstuff, it is important to identify where the ⁸⁷ Sr/⁸⁶ Sr signature in food comes from, and the methods of ⁸⁷ Sr/⁸⁶ Sr ratio analysis in food and environmental samples. Wheat with three genotypes, soil and groundwater samples were collected from three regions of China during harvest time of 2014. The ⁸⁷ Sr/⁸⁶ Sr ratios in the samples were determined by thermal ionization mass spectrometer in order to investigate the possible source of ⁸⁷ Sr/⁸⁶ Sr in wheat, and the concentrations of Rb and Sr in wheat and soils were also detected by inductively coupled plasma mass spectrometry and combined with ⁸⁷ Sr/⁸⁶ Sr ratio in order to trace the geographical origin of wheat. The ⁸⁷ Sr/⁸⁶ Sr ratio, the contents Rb and Sr, and Rb/Sr ratio of wheat and soil samples showed significant differences among three regions. The ⁸⁷ Sr/⁸⁶ Sr ratios and the concentrations of Rb and Sr in soils were higher than those in corresponding wheat. The ⁸⁷ Sr/⁸⁶ Sr ratio in wheat was identical to that corresponding soil NH₄ NO₃ extracts (labile fraction of soil) and groundwater. Wheat uptake more Rb than Sr. 3D distribution of ⁸⁷ Sr/⁸⁶ Sr, Rb and Sr could identify wheat samples from different regions clearly. The ⁸⁷ Sr/⁸⁶ Sr ratio of wheat reflects the ⁸⁷ Sr/⁸⁶ Sr ratio of the associated environment including soil and groundwater. It is expected that the use the parameters of ⁸⁷ Sr/⁸⁶ Sr ratio, the contents of Rb and Sr will allow to trace geographical origin of wheat. Copyright © 2017 John Wiley & Sons, Ltd.

Regulation of EPS production in Lactobacillus casei LC2W through metabolic engineering

Lactobacillus casei LC2W is an exopolysaccharide(EPS)-producing strain with probiotic effects. The low efficiency and unclear regulation mechanism of EPS biosynthesis have become main constraints for its application in food industry. To investigate the major rate-limiting factors of EPS biosynthesis and to improve its yield, metabolic engineering was applied to this strain. Eight relevant genes related to central metabolism, sugar-nucleotides supply, glycosyltransferase and cofactor engineering were cloned and overexpressed. The results suggested that nox, pfk, rfbB and galT genes were the largest contributors to EPS biosynthesis in this study, which elevated EPS yield by 46·0, 20, 17·4 and 19·6% respectively. Notably, under aerobic condition which was not a suitable condition for lactobacilli to grow in, recombinant strain LC-nox achieved the highest EPS yield of 263·7 mg l(-1) , which was increased by 75% compared to that of the starting strain. The oxygen stress was excluded since the phenomenon was not observed in the control strain under the same condition. Therefore, it was probably that higher NADH oxidase activity led to a decreased NADH availability and reduced lactate concentration, which resulted in the elevation of EPS yield.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study contributed to the understanding of EPS biosynthesis in Lact. casei through metabolic engineering and provided a starting point for introducing cofactor engineering into this strain. Overexpression of NADH oxidase was found to have a most significant effect on the EPS production. It is the first report that EPS could be accumulated to such a high level under aerobic condition in lactobacilli. Our results provided a novel strategy for the improvement of EPS production in lactic acid bacteria.

Inertial focusing of ellipsoidal Euglena gracilis cells in a stepped microchannel

Euglena gracilis (E. gracilis) has recently been attracting attention as a potential renewable source for the production of biofuels, livestock feed, cosmetics, and dietary supplements. Research has focused on strain isolation, productivity improvement, nutrient and resource allocation, and co-product production, key steps that ultimately determine the economic viability and compatibility of the biomass produced. To achieve these characteristics, approaches to select E. gracilis mutants with desirable properties, such as high wax ester content, high growth rate, and high environmental tolerance for biodiesel and biomass production, are needed. Flow-based analysis and sorting can be rapid and highly automated but calls for techniques that can precisely control the position of E. gracilis with varying sizes and shapes in a tightly focused stream in a high-throughput manner. In this work, we use a stepped microchannel consisting of a low-aspect-ratio straight channel and a series of expansion regions along the channel height. We study horizontal and vertical focusing, orientation, rotational, and translational behaviors of E. gracilis as a function of aspect ratio (AR) and channel Reynolds number (Re). By making use of inertial focusing and local secondary flows, E. gracilis with diverse shapes are directed to a single equilibrium position in a single focal stream. As an application of on-chip flow cytometry, we integrate a focusing microchip with a custom laser-two-focus (L2F) optical system and demonstrate the detection of chlorophyll autofluorescence as well as the measurement of the velocity of E. gracilis cells flowing through the microchannel.

Tumorigenic potential is restored during differentiation in fusion-reprogrammed cancer cells

Detailed understanding of the mechanistic steps underlying tumor initiation and malignant progression is critical for insights of potentially novel therapeutic modalities. Cellular reprogramming is an approach of particular interest because it can provide a means to reset the differentiation state of the cancer cells and to revert these cells to a state of non-malignancy. Here, we investigated the relationship between cellular differentiation and malignant progression by the fusion of four independent mouse cancer cell lines from different tissues, each with differing developmental potentials, to pluripotent mouse embryonic stem (ES) cells. Fusion was accompanied by loss of differentiated properties of the four parental cancer cell lines and concomitant emergence of pluripotency, demonstrating the feasibility to reprogram the malignant and differentiative properties of cancer cells. However, the original malignant and differentiative phenotypes re-emerge upon withdrawal of the fused cells from the embryonic environment in which they were maintained. cDNA array analysis of the malignant hepatoma progression implicated a role for Foxa1, and silencing Foxa1 prevented the re-emergence of malignant and differentiation-associated gene expression. Our findings support the hypothesis that tumor progression results from deregulation of stem cells, and our approach provides a strategy to analyze possible mechanisms in the cancer initiation.

Effectiveness and cost-effectiveness of a brief school-based group programme for parents of children at risk of ADHD: a cluster randomised controlled trial

BACKGROUND

National Institute for Health and Care Excellence guidelines recommend a stepped care approach for the identification and management of children with, or at risk of, attention-deficit/hyperactivity disorder (ADHD). We investigated the effectiveness, cost-effectiveness and acceptability of a group parenting intervention programme (+/- a teacher session) for children at risk of ADHD.

METHODS

In a three-arm cluster randomised controlled trial, 12 primary schools were randomly assigned to control, parent-only and combined (parent + teacher) intervention arms. Eligible children had high levels of parent-rated hyperactivity/inattention (n = 199). At 6 month follow-up, the primary outcome measure was the parent-completed Conners' Rating Scale - Revised (ADHD index). Secondary outcomes included the Conners' sub-scales (hyperactivity, cognitive problems/inattention and oppositional behaviour), the teacher-completed Conners' Rating Scale - Revised, child health-related quality of life, parental burden and parental mental health. The cost-effectiveness analyses reflected a health and personal social services perspective.

TRIAL REGISTRATION

ISRCTN87634685.

RESULTS

Follow-up data were obtained from 76 parents and 169 teachers. There was no effect of the parent-only (mean difference = -1.1, 95% CI -5.1,2.9; p = 0.57) or combined interventions (mean difference = -2.1, 95% CI -6.4,2.1; p = 0.31) on the ADHD index. The combined intervention was associated with reduced parent-reported hyperactivity symptoms (mean difference = -5.3; 95% CI -10.5,-0.01; p = 0.05) and the parent-only intervention with improved parental mental health (mean difference = -1.9; 95% CI -3.2,-0.5; p = 0.009). The incremental costs of the parent-only and the combined interventions were £73 and £123, respectively. Above a willingness-to-pay of £31 per one-point improvement in the ADHD index, the parent-only programme had the highest probability of cost-effectiveness. Participants found the interventions acceptable.

CONCLUSIONS

For children at risk of ADHD, this school-based parenting programme was not associated with improvement in core ADHD symptoms. Secondary analyses suggested a possible reduction in parent-reported hyperactivity and parental mental health problems. Future research should compare targeted interventions against watchful waiting and specialist referral.

Class I HDAC inhibitor mocetinostat induces apoptosis by activation of miR-31 expression and suppression of E2F6

The class I selective inhibitor of the histone deacetylases, mocetinostat, has promising antitumor activities in both preclinical studies and the clinical trials. To understand how mocetinostat induces apoptosis, we examined the effects of mocetinostat on miR-31, a proapoptotic microRNA that was previously found to be epigenetically silenced in prostate cancer. We found that miR-31 was significantly upregulated by mocetinostat in prostate cancer cells. Antiapoptotic protein E2F6, the target of miR-31, was decreased by mocetinostat treatment. When miR-31 was blocked with an inhibitor, the ability of mocetinostat to induce apoptosis was reduced. We further demonstrated that mocetinostat enhanced the activity of docetaxel in apoptosis induction. While siRNA knockdown of E2F6 sensitized cancer cells to mocetinostat-induced apoptosis, overexpression of E2F6 blocked mocetinostat-induced apoptosis. In an orthotopic xenograft model, we demonstrated that mocetinostat activated miR-31, decreased E2F6, induced apoptosis, and significantly reduced prostate cancer growth. Importantly, we found that mocetinostat also increased miR-31 expression, decreased E2F6, and induced apoptosis in the primary prostate cancer stem cells. Thus, activation of miR-31 and downregulation of E2F6 constitute an important mechanism in mocetinostat-induced apoptosis in prostate cancer.

First Measurement of Electron Neutrino Appearance in NOvA

We report results from the first search for ν_{μ}→ν_{e} transitions by the NOvA experiment. In an exposure equivalent to 2.74×10^{20} protons on target in the upgraded NuMI beam at Fermilab, we observe 6 events in the Far Detector, compared to a background expectation of 0.99±0.11(syst) events based on the Near Detector measurement. A secondary analysis observes 11 events with a background of 1.07±0.14(syst). The 3.3σ excess of events observed in the primary analysis disfavors 0.1π<δ_{CP}<0.5π in the inverted mass hierarchy at the 90% C.L.

Self-assembled nanoparticles covalently consisting of doxorubicin and EDB fibronectin specific peptide for solid tumour treatment

We developed a facile modality to prepare nanoparticles consisting of doxorubicin and ZD2 motif for treating solid tumours. The nanoparticles showed great preferential cellular uptake in PC3 cells, high cell suppression, and strong anti-tumour ability.

The electrochemical sensor based on electrochemical oxidation of nitrite on metalloporphyrin–graphene modified glassy carbon electrode

In this study, 5-(4-aminophenyl)-10,15,20-triphenylporphyrin]Mn(iii) (MnNH₂TPP) and graphene oxide (GO) composite materials (GO–MnNH₂TPP) were successfully used to modify a glassy carbon electrode (GC) by the drop casting method.

Electrodeposition on pyrite from copper(i) cyanide electrolyte

Copper anodically deposits on pyrite from cyanide bearing solution at neutral pH, and cathodically deposits at mildly acidic pH.