Estrogen receptor (ESR) 2 partially offsets the absence of ESR1 in gonadotropes of pituitary-specific Esr1 knockout female mice

Estrogen receptor 1 and 2 (ESR1 and 2) mediate estrogen (E) action on gonadotrope function. While much is known about the effects of ESR1 on the gonadotrope, there is still some controversy regarding the effects of ESR2. To investigate the role of ESR2 in the gonadotrope, 45-day-old female mice of two different genotypes were used: wild type (WT) and pituitary (gonadotropes and thyrotropes)-specific Esr1 knockout (KO). All mice were ovariectomized (OVX) and 15 days later injected over 3 days with 2.5 μg 17β-estradiol (E(2)), 0.2 mg of the selective ESR1 or 2 agonists, propylpyrazole triol and diarylpropionitrile, respectively, or 0.1 ml oil. The day after treatment, anterior pituitary glands were dissected out for evaluation of gonadotrope ultrastructural morphology and pituitary immunohistochemical expression of progesterone receptor (Pgr (Pr)). Blood was collected and serum LH levels were assessed. Activation of ESR1 in WT mice resulted in the following: i) uterine ballooning and vaginal cornification, ii) negative feedback on LH secretion, iii) increased number of homogeneous (functional) gonadotropes, and iv) pituitary Pgr expression (35.9±2.0% of pituitary cells). Activation of ESR1 in KO mice induced normal uterine, vaginal, and LH secretion responses, but failed to increase the number of functional gonadotropes, and induced significantly lower Pgr expression (21.0±3.0% of pituitary cells) than in WT mice. Whilst activation of ESR2 had no significant effects in WT mice, it doubled the number of functional gonadotropes exhibited by KO mice injected with oil. It is concluded that E(2) exerted its action in KO mouse gonadotropes via ESR2.     

Acute metabolic responses to butter,margarine, and a monoglyceride gel-structured spread

Cardiovascular and metabolic health concerns have led to interest in development of saturated- and trans fat-free margarines, spreads, and other foods. We have recently characterized a novel monoglyceride gel (MAG GEL) that can structure liquid oil into a semi-plastic solid consistency in the absence of saturated and trans fats. Consumption of this MAG GEL resulted in tempered postprandial metabolic responses compared to those resulting from consumption of a compositionally equivalent but unstructured oil suspension, suggesting a structure-dependent metabolic response. The current study was designed to test the hypothesis that postprandial blood lipid and metabolite responses to MAG GEL would be tempered compared to the responses after ingestion of butter and tub-margarine of equal total fat content. Indeed, blood triglyceride response was tempered in MAG GEL compared to butter, margarine, and unstructured oil trials, all of which produced similar triglyceride responses. The blood free fatty acid, glucose, and insulin responses were not different in MAG GEL compared to butter or margarine trials; and interestingly, there were no differences between butter and margarine trials for any of the metabolic response variables. The MAG GEL is a useful structure for many applications, and produces salubrious postprandial metabolic effects compared to other spreadable fats.     

Hybrid trust and weight evaluation-based trust assessment using ECK-ANFIS and AOMDV-REPO-based optimal routing in MANET environment

Many researchers have been inspired to work on diverse challenges by a particularly favourable platform, namely mobile ad hoc networks (MANET) routing optimization. However, the lack of trust assessment is one of MANET’s main flaws. As a result, trust-based routing has received increasing attention in MANET over the last few years. Hence, the majority of recent work has focused on the development of routing protocols for security enhancement in a hostile environment. However, on the MANET environment, these protocols have many weaknesses and are also not that much secure. Hence, the primary goal of this study is to design a framework for balancing multiple performance measures in order to find the optimal multipath routing solution. In this scheme, we have employed the exponential cauchy kernelized adaptive neuro-fuzzy inference system (ECK-ANFIS) focused trust assessment with hybrid trust (HT) evaluation and optimal MANET routing. The ECK-ANFIS evaluates the trust after the nodes are initialised where, HT and the weight value, which are estimated for each node throughout the evaluation. The performance of the proposed mechanism has been measured using the various metrics defined in the existing protocols and also proved the superiority of the scheme by comparing it with other related ones.

     

Effect of food preparation on the structure and metabolic responses to a monostearin–oil–water gel-based spread

Widespread recognition of the negative health effects of trans and saturated fats has prompted research to develop alternative structures that can structure liquid oils into semi-solid plastic pastes for food applications. We have recently developed and described the physical chemical properties of a unique a monostearin–oil–water gel (MAG) that achieves this goal. Furthermore, ingestion of this MAG in the form of a margarine-like spread resulted in beneficial suppression of blood lipid and insulin responses in humans compared to compositionally-equivalent controls lacking the MAG structure. However, the integrity of this novel structure and its salubrious metabolic effects have not been previously evaluated under food processing conditions. The purpose of the current study was to evaluate the integrity of the MAG when applied to toasted bread and when mixed with a warm pasta meal, and to evaluate the metabolic effects over 6 h following ingestion of both types of meals with MAG compared to compositionally-equivalent unstructured oil preparations. MAG structure was maintained in the toast study, but the pasta meal destroyed the MAG structure. Triglyceride, free fatty acid, and insulin responses were suppressed in the MAG trial compared to the unstructured oil trial of the toast study, whereas there was no difference in the responses of these variables between the two trials in the pasta study. The results demonstrate for the first time that the metabolic effects of MAG depend on maintenance of the MAG structural integrity throughout the food processing procedures leading up to ingestion. Thus, this study demonstrates the utility of MAG as a trans- and saturated fat-free vehicle to structure and deliver liquid oil as a semi-solid plastic paste, and establishes processing limits to the integrity of the additional beneficial metabolic effects of this novel structure.     

Antimicrobial susceptibility of Staphylococcus aureus from retail ground meats

The aim of this study was to characterize antimicrobial resistance in Staphylococcus aureus, including methicillin-resistant S. aureus (MRSA), recovered from raw retail meat products purchased in the Washington, D.C., area. From March to August 2008, 694 samples of ground beef (n = 198), ground pork (n = 300), and ground turkey (n = 196) were collected by random sampling from stores of three grocery chains. In total, 200 S. aureus isolates (29%) were recovered by direct plating. When tested for susceptibility to 22 antimicrobials, 69% of the S. aureus isolates were resistant to tetracycline, 26% to penicillin, 17% to ampicillin, 13% to methicillin, 8% to erythromycin, 4.5% to clindamycin, 1.5% to gentamicin, and 0.5% to chloramphenicol, oxacillin, cefoxitin, or quinupristin-dalfopristin. However, 27% of the isolates were susceptible to all tested antimicrobials. More turkey and pork isolates were resistant to ampicillin, penicillin, and tetracycline than were beef isolates (P < 0.05). Additionally, 17% of the turkey and 17% of the pork isolates were resistant to methicillin (MIC ≥ 16 μg/ml), whereas no beef isolates were resistant to the antimicrobial agent. A single MRSA (methicillin MIC > 32 μg/ml) isolate containing the mecA gene with additional resistance to erythromycin, clindamycin, oxacillin plus 2% NaCl, cefoxitin, ampicillin, penicillin, quinupristin-dalfopristin, tetracycline, and gentamicin was recovered from one pork sample. The presence of antimicrobial-resistant S. aureus, coupled with the relative lack of such studies in the United States, suggests that further investigations on MRSA in the food supply are needed despite the low rate of MRSA found in this particular study.