Insulin responses to acute glucose infusions in Buša and Holstein-Friesian cattle breed during the peripartum period: Comparative study

The aim of this study was to compare insulin responsevness to acute glucose infusion in cows of Holstein Friesian (HF) and Buša breeds during the peripartal period. Eight cows per each group (HF and Buša), were chosen. At day 7 prior to calving (ante partum) and day 14 after calving (post partum) animals were subjected to a glucose tolerance test (GTT). Blood samples were taken immediately before infusion and 15, 30, 60, 120 and 180 min thereafter. Glucose and insulin concentrations were measured in each blood sample, while BHBA and NEFA were measured only in samples taken before the infusion. QUICKY an indicator of insulin resistance in cows was calculated. Basal glycemia did not significantly differ between the breeds. Basal insulinemia was significantly higher in Buša than in HF cows in both examined periods (p<0.001, respectively). Basal NEFA levels tended (p=0.06) to be higher in Buša cows compared with those of HF ante partum, and was significantly higher (p<0.001) post partum. Basal BHBA was significantly lower in Buša than HF cows in both examined periods (p<0.01; p<0.001). QUICKI was significantly lower in Buša compared to HF cows both ante partum and post partum periods (p<0.001, respectively). Glycemia determined during GTT were higher in Buša than HF cows, both ante partum and post partum, but significantly starting from minute 15 ante partum i.e. minute 30 post partum. Insulinemia determined during GTT was significantly lower at min 15, and significantly higher starting from min 90 in Buša than HF cows, both ante partum and post partum. Results obtained in this study indicate on difference in insulin responsevness to acute glucose infusion between the examined breeds, which is probably a consequence of the difference in the degree of negative energy balance rather than of selection on high milk production. Namely, decreased insulin tissues sensitivity and decreased insulin responsiveness in Buša compared to HF cows is probably the consequence of inadequate energy intake from alimentary sources which leads to enhanced usage of energy from body reserves. [Projekat Ministarstva nauke Republike Srbije, br. 46002

Regulation of protein synthesis in mammary glands of lactating dairy cows by starch and amino acids

The objective of this study was to evaluate local molecular adaptations proposed to regulate protein synthesis in the mammary glands. It was hypothesized that AA and energy-yielding substrates independently regulate AA metabolism and protein synthesis in mammary glands by a combination of systemic and local mechanisms. Six primiparous mid-lactation Holstein cows with ruminal cannulas were randomly assigned to 4 treatment sequences in a replicated incomplete 4 x 4 Latin square design experiment. Treatments were abomasal infusions of casein and starch in a 2 x 2 factorial arrangement. All animals received the same basal diet (17.6% crude protein and 6.61 MJ of net energy for lactation/kg of DM) throughout the study. Cows were restricted to 70% of ad libitum intake and abomasally infused for 36 h with water, casein (0.86 kg/d), starch (2 kg/d), or a combination (2 kg/d starch + 0.86 kg/d casein) using peristaltic pumps. Milk yields and composition were assessed throughout the study. Arterial and venous plasma samples were collected every 20 min during the last 8 h of infusion to assess mammary uptake. Mammary biopsy samples were collected at the end of each infusion and assessed for the phosphorylation state of selected intracellular signaling molecules that regulate protein synthesis. Animals infused with casein had increased arterial concentrations of AA, increased mammary extraction of AA from plasma, either no change or a trend for reduced mammary AA clearance rates, and no change in milk protein yield. Animals infused with starch had increased milk and milk protein yields, increased mammary plasma flow, reduced arterial concentrations of AA, and increased mammary clearance rates and net uptake of some AA. Infusions of starch increased plasma concentrations of glucose, insulin, and insulin-like growth factor-I. Starch infusions increased phosphorylation of ribosomal protein S6 and endothelial nitric oxide synthase, consistent with changes in milk protein yields and plasma flow, respectively. Phosphorylation of the mammalian target of rapamycin was increased in response to starch only when casein was also infused. Thus, cell signaling molecules involved in the regulation of protein synthesis differentially responded to these nutritional stimuli. The hypothesized independent effects of casein and starch on animal metabolism and cell signaling were not observed, presumably because of the lack of a milk protein response to infused casein

Anti-counterfeiting: Mixing the Physical and the Digital World

In this paper, we overview a set of desiderata for building digital anti-counterfeiting technologies that rely upon the difficulty of manufacturing randomized complex 3D objects. Then, we observe how this set is addressed by RF-DNA, an anti-counterfeiting technology recently proposed by DeJean and Kirovski. RF-DNA constructs certificates of authenticity as random objects that exhibit substantial uniqueness in the electromagnetic domain

Characterization of MTAP gene expression in breast cancer patients and cell lines

MTAP is a ubiquitously expressed gene important for adenine and methionine salvage. The gene is located at 9p21, a chromosome region often deleted in breast carcinomas, similar to CDKN2A, a recognized tumor suppressor gene. Several research groups have shown that MTAP acts as a tumor suppressor, and some therapeutic approaches were proposed based on a tumors\ub4 MTAP status. We analyzed MTAP and CDKN2A gene (RT-qPCR) and protein (western-blotting) expression in seven breast cancer cell lines and evaluated their promoter methylation patterns to better characterize the contribution of these genes to breast cancer. Cytotoxicity assays with inhibitors of de novo adenine synthesis (5-FU, AZA and MTX) after MTAP gene knockdown showed an increased sensitivity, mainly to 5-FU. MTAP expression was also evaluated in two groups of samples from breast cancer patients, fresh tumors and paired normal breast tissue, and from formalin-fixed paraffin embedded (FFPE) core breast cancer samples diagnosed as Luminal-A tumors and triple negative breast tumors (TNBC). The difference of MTAP expression between fresh tumors and normal tissues was not statistically significant. However, MTAP expression was significantly higher in Luminal-A breast tumors than in TNBC, suggesting the lack of expression in more aggressive breast tumors and the possibility of using the new approaches based on MTAP status in TNB

General Terms Electronic

The widespread use of mobile, personal computing devices, together with recent advances in wireless communication technologies, pose a myriad of new opportunities for leveraging the commerce of digital goods. We envision a novel platform for the free-trade of digital content where ordinary users are allowed to market and resell copies of digital content to neighbors in their wireless devices ’ vicinity. By keeping significant part of the revenues, users are likely to drive the sales for their and copyright holders ’ economic benefit. While the marketing, commitment and, optionally, the download of the content is peer-to-peer, the act of finalizing a transaction, i.e., updating users ’ accounts, is based on a client-server architecture. Transactions among users can be performed off-line, without the immediate assistance of the copyright holder or any central entity, with their integrity being enforced by a cryptographic protocol. Combined with the use of tamper-resistant hardware, the system delivers a simple digital rights management policy, relying on incentive-based mechanisms to sustain the economy. In this paper, we focus on demonstrating the technical feasibility of our ideas. We discuss typical use case scenarios and present a GUI mockup with the interaction steps needed for using most of the system’s functionality. We present the cryptographic protocol used to ensure the integrity of purchase transactions and address the main features of the system from an implementation standpoint. Finally, we anticipate exceptional situations that may arise and show how they are handled in the platform

Down-regulation of methylthioadenosine phosphorylase (MTAP) induces progression of hepatocellular carcinoma via accumulation of 5'-deoxy-5'-methylthioadenosine (MTA)

Recently, we have shown that down-regulation of methylthioadenosine phosphorylase (MTAP) in hepatocellular carcinoma (HCC) cells enhances the invasive potential and the resistance against cytokines. Here, we aimed at investigating the molecular mechanism underlying this tumor-promoting effect and expanded the analysis to a large series of human HCC tissues. Liquid chromatography tandem mass spectrometry revealed that reduced MTAP expression resulted in higher intra- and extracellular concentrations of 5'-deoxy-5'-methylthioadenosine (MTA) in cultivated HCC cells and, concordantly, higher levels of MTA in HCC tissue. MTA induced matrix metalloproteinase (MMP) and interleukin-8 transcription in HCC cells in vitro, accompanied by enhanced proliferation and activation of the transcription factor NFκB. In addition, MTA secreted by HCC cells induced expression of fibroblast growth factor-2 and MMP1 in stromal myofibroblasts. In human HCC tissues, MTAP mRNA correlated inversely with MTA levels, and immunohistochemical analysis of a tissue microarray of 140 human HCCs revealed that low MTAP protein expression correlated with advanced tumor stages. In conclusion, MTAP deficiency results in accumulation of MTA, which is associated with increased tumorigenicity. These data further indicate MTAP as a tumor suppressor in HCC, and MTA as a potential biomarker for HCC progression

A multi-scale computational approach to understanding cancer metabolism

A first principles Nash equilibrium approach to modeling, simulation, and analysis of metabolic pathways is presented. The modeling framework is described in detail, and small examples illustrating mass and charge balancing, the inclusion of enzymatic reactions in the model, constraint linear independence, and allosteric inhibition are given in order to provide a tutorial for the reader. The methodology is then applied to the methionine salvage pathway in order to demonstrate that it can correctly capture the behavior of an important pathway in the study of cancer. It is shown that methylthioadenosine (MTA) accumulation as a result of the loss of activity of the enzyme S-methyl-5′-thioadenosine phosphorylase (MTAP) is correctly predicted by the Nash equilibrium approach under tight regulation of adenine. Several examples are presented to elucidate the key ideas in modeling cancer metabolism using the Nash equilibrium approach