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The PI3K/AKT/mTOR (phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin) pathway can be initiated by PROK1 (prokineticin 1), but its effect and mechanism of action in pancreatic carcinoma (PC) are not fully understood. In this study, we elucidated the roles of PROK1 and its related molecules in PC in vivo. PANC-1 cells with PROK1 knockdown were injected into BALB/c nude mice. The growth and weight of the tumor were monitored and measured, which was followed by TUNEL (terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling), immunohistochemical staining, and hematoxylin and eosin staining. The key proteins related to proliferation, apoptosis, and the PI3K/AKT/mTOR pathway were determined by Western blotting. We also used public databases to identify the molecules related to PROK1. The reduction of PROK1 inhibited angiopoiesis and promoted apoptosis in vivo. PCNA-1, cyclin D1, and Bcl-2 decreased considerably, while Bax and cleaved caspase-3 increased significantly after PROK1 inhibition. The PI3K/AKT/mTOR signal inhibition was also closely associated with PROK1 knockdown. The possible related molecules of PROK1, such as von Willebrand factor, were screened and considered to be involved in the aberrant activation of PI3K/AKT. In conclusion, PROK1 knockdown significantly prevented tumor growth and promoted apoptosis of human PC cells in vivo, where the PI3K/AKT/mTOR pathway was probably inhibited. Therefore, PROK1, along with its related molecules, might be important targets for PC therapy.

This paper aims to answer the fundamental but still unan-swered question: how can brains represent 3D objects? Ratherthan building a model of visual processing, we focus on mod-eling the haptic sensorimotor processes through which objectsare explored by touch. This idea is inspired from two mainfacts: 1) in developmental terms, tactile exploration is the pri-mary means by which infants learn to represent object shapes;2) blind people can also represent and distinguish objects justby haptic exploration. Therefore, in this paper, we firstly es-tablish the relationship between the geometric properties of anobject and constrained navigation action sequences for tactileexploration. Then, a neural network model is proposed to rep-resent 3D objects from these experiences, using a mechanismthat is computationally similar to that used by hippocampalplace cells. Simulation results based on a 2 × 2 × 2 cube anda 3 × 2 × 1 cuboid show that the proposed model is effectivefor representing 3D objects via tactile exploration and compar-ative results suggest that the model is more efficient and accu-rate when learning a representation of the 3×2×1 cuboid withan asymmetrical geometrical structure than the 2 × 2 × 2 cubewith a symmetrical geometrical structure.

Horizontal connections in the primary visual cortex have been hypothesized to play a number of computational roles: association field for contour completion, surface interpolation, surround suppression, and saliency computation. Here, we argue that horizontal connections might also serve a critical role for computing the appropriate codes for image representation. That the early visual cortex or V1 explicitly represents the image we perceive has been a common assumption in computational theories of efficient coding (Olshausen and Field (1996)), yet such a framework for understanding the circuitry in V1 has not been seriously entertained in the neurophysiological community. In fact, a number of recent fMRI and neurophysiological studies cast doubt on the neural validity of such an isomorphic representation (Cornelissen et al., 2006; von der Heydt et al., 2003). In this study, we investigated, neurophysiologically, how V1 neurons respond to uniform color surfaces and show that spiking activities of neurons can be decomposed into three components: a bottom-up feedforward input, an articulation of color tuning and a contextual modulation signal that is inversely proportional to the distance away from the bounding contrast border. We demonstrate through computational simulations that the behaviors of a model for image representation are consistent with many aspects of our neural observations. We conclude that the hypothesis of isomorphic representation of images in V1 remains viable and this hypothesis suggests an additional new interpretation of the functional roles of horizontal connections in the primary visual cortex.

The objective of this experiment was to determine the energy values and nutrient utilisation of five corns at starer (14–16 days) and grower (28–30 days) phases. The 1–5 corn samples were obtained from Jinzhou, Liaoning; Gongzhuling, Jilin; Qingdao, Shandong; Songyuan, Jilin and Xinxiang, Henan, China. Each phase of the trial consisted of six treatments with six replicates each. The number of birds per replicate was 4 (Days 14–16) and 2 (Days 28–30). Diets included a corn–soybean meal basal diet and five test diets contained 30% of each corn sample, which replaced 30% of the energy‐yielding components of the basal diet (as‐fed basis). The trial consisted of six cycles, each cycle was 7 days, including 4 days for adaptation to feed. On Day 4, the birds were transferred to the respiration chambers. In the following 3 days, total excreta were collected and daily heat production was measured. The apparent total tract retention of dry matter, crude protein, ether extract, and starch improved with age, showing the same trend as energy values. The nitrogen‐corrected metabolisable energy (AMEn) values for corn samples at the starter phase were in the range of 16.25–17.41 MJ/kg DM and at the grower phase were in the range of 17.23–17.60 MJ/kg DM. On the other hand, the net energy (NE) values of the five corn samples ranged from 9.93 to 11.67 MJ/kg DM during the starter period and from 11.19 to 12.27 MJ/kg DM during the grower period. The AMEn and NE values of the five corn samples were close to the literature values for corn. Results from our research indicated the nutrient digestibility and energy values of corn samples increase with the age of the broiler. [ABSTRACT FROM AUTHOR]

This study was done to compare the energy and nutrient utilisation of corn in Arbor Acres (AA) broilers and Beijing You (BJY) chickens. BJY chickens with the same age as AA broilers were named BJY1 chickens, and with the same body weight as AA broilers were named BJY2 chickens. Three groups of broilers (36 male AA broilers, 72 male BJY1 chickens, and 36 male BJY2 chickens), 2 treatments per group, 6 replicates per treatment, 3 chickens or 6 chickens per replicate. During each period, birds were fed in chambers for 11 days, including 5 days for adaptation to the feed, 3 days for excreta and gas data collection and another 3 days for fasting were recorded. Results showed that the fasting heat production (FHP) of AA, BJY1 and BJY2 chickens gradually stabilised after fasting for 72 h, the FHP of AA, BJY1 and BJY2 chickens were 486.54, 536.22 and 548.90 KJ/kg BW0.70/day respectively. AA broilers had significantly lower (p < 0.01) apparent total tract digestibility (ATTD) of starch in corn than that of BJY1 and BJY2 chickens, whereas there were no significant differences (p > 0.05) observed in ATTD of dry matter, crude protein, ether extract and crude fibre. The apparent metabolisable energy (AME) values of corn in AA, BJY1 and BJY2 chickens were 16.18, 16.81, and 16.39 MJ/kg dry matter (DM) and the corresponding nitrogen‐corrected AME (AMEn) values were 15.71, 16.38 and 15.99 MJ/kg DM respectively. The net energy (NE) values of corn in AA, BJY1 and BJY2 chickens were 12.03, 12.28 and 11.97 MJ/kg DM respectively. In conclusion, BJY chickens had a higher maintenance energy requirement than that of AA broilers, and AA broilers of the same age and weight as BJY chickens showed no significant differences in AME, AMEn and NE values of corn. [ABSTRACT FROM AUTHOR]

Sodium bicarbonate pretreatment and solid-state fermentation (SSF) were used to maximize the nutritional value of corn germ meal (CGM) by inoculating it with Bacillus velezensis CL-4 (isolated from chicken cecal contents and capable of degrading lignocellulose). Based on genome sequencing, B. velezensis CL-4 has a 4,063,558 bp ring chromosome and 46.27% GC content. Furthermore, genes associated with degradation of lignocellulose degradation were detected. Pretreatment of CGM (PCGM) with sodium bicarbonate (optimized to 0.06 g/mL) neutralized low pH. Fermented and pretreated CGM (FPCGM) contained more crude protein (CP), soluble protein of trichloroacetic acid (TCA-SP), and total amino acids (aa) than CGM and PCGM. Degradation rates of cellulose and hemicellulose were reduced by 21.33 and 71.35%, respectively, after 48 h fermentation. Based on electron microscopy, FPCGM destroys the surface structure and adds small debris of the CGM substrate, due to lignocellulose breakdown. Furthermore, 2-oxoadipic acid and dimethyl sulfone were the most important metabolites during pretreatment. Concentrations of adenosine, cytidine, guanosine, S-methyl-5'-thioadenosine, and adenine decreased significantly after 48 h fermentation, whereas concentrations of probiotics, enzymes, and fatty acids (including palmitic, 16-hydroxypalmitic, and linoleic acids) were significantly improved after fermentation. In conclusion, the novel pretreatment of CGM provided a proof of concept for using B. velezensis CL-4 to degrade lignocellulose components, improve nutritional characteristics of CGM, and expand CGM lignocellulosic biological feed production. Key points: • Sodium bicarbonate (baking soda) can be used as an economical and green additive to pretreat corn germ meal; • Fermentation with B. velezensis degrades the cellulose and hemicellulose component of corn germ meal and improves its feed quality; • As a novel qualified presumption of safety (QPS) strain, B. velezensis should have broad potential applications in food and feed industries. [ABSTRACT FROM AUTHOR]