Ghrelin stimulates food intake and growth hormone release in rats with thermal injury: synthesis of ghrelin

Ghrelin, a 28-residue octanoylated peptide recently isolated from the stomach, exhibits anti-cachectic properties through regulating food intake, energy expenditure, adiposity, growth hormone secretion and immune response. Burn injury induces persistent hypermetabolism and muscle wasting. We therefore hypothesized that ghrelin may also play a role in the pathophysiology of burn-induced cachexia. Overall ghrelin expression in the stomach over 10 days after burn was significantly decreased (p = 0.0003). Total plasma ghrelin was reduced 1 day after burn. Thus, changes in ghrelin synthesis and release may contribute to burn-induced dysfunctions. Ghrelin (30 nmol/rat, i.p.) greatly stimulated 2 h food intake in rats on five separate days after burn and in control rats. On post-burn day 15, plasma growth hormone levels were significantly lower than in controls, and this was restored to normal levels by ghrelin (10 nmol/rat, i.p.). These observations suggest that ghrelin retains its ability to favorably modulate both the peripheral anabolic and the central orexigenic signals, even after thermal injury despite ongoing changes due to prolonged and profound hypermetabolism, suggesting that long-term treatment with ghrelin may attenuate burn-induced dysfunctions.     

The Biology and Ecology of Feral Alfalfa (Medicago sativa L.) and Its Implications for Novel Trait Confinement in North America

Alfalfa (Medicago sativa) is an important forage crop worldwide. Apart from cultivated fields, alfalfa is also found along roadsides and in natural and semi-natural habitats. However, little information is available on the establishment capabilities of alfalfa in noncultivated areas and the potential of these founding populations to become feral. Some crop species have not lost all their wild characteristics during the domestication process and with several inherent traits favoring weediness, alfalfa could be one among those that can become feral. There is great interest in the feral potential of alfalfa, particularly due to the concerns that feral plants could act as genetic bridges and facilitate novel trait movement at the landscape level. Alfalfa is the first perennial, insect-pollinated crop to be genetically engineered and approved for unconfined release into the environment. This review investigates and compiles information in the literature that reveals the life history components that can influence ferality in alfalfa. Characteristics that can contribute to ferality in alfalfa include high genetic diversity, perenniality, quick regrowth potential, persistence, symbiotic nitrogen fixation, deep tap root system, drought and cold tolerance, and seed dormancy. With these traits, alfalfa is equipped to invade and dominate unmanaged habitats. Feral alfalfa populations can and will act as bridges for long-distance gene flow and facilitate the adventitious presence of novel traits in the environment. As such, feral populations will become a potential barrier for achieving coexistence of transgenic and nontransgenic alfalfa fields. Implications of ferality, including gene flow and hybridization with compatible wild relatives are also discussed in detail. This review serves as a resource for environmental risk assessment for the release of alfalfa containing novel traits.     

Cadmium-induced oxidative stress in Saccharomyces cerevisiae

The present study was undertaken to determine the effect of cadmium (Cd) on the antioxidant status of the yeast Saccharomyces cerevisiae. S. cerevisiae serves as a good eukaryotic model system for the study of the molecular mechanisms of oxidative stress. We investigated the adaptative response of S. cerevisiae exposed to Cd. Yeast cells could tolerate up to 100 microM Cd and an inhibition in the growth and viability was observed. Exposure of yeast cells to Cd showed an increase in malondialdehyde and glutathione. The activities of catalase, superoxide dismutase and glutathione peroxidase were also high in Cd-exposed cells. The incorporation of Cd led to significant increase in iron, zinc and inversely the calcium, copper levels were reduced. The results suggest that antioxidants were increased and are involved in the protection against macromolecular damage during oxidative stress; presumably, these enzymes are essential for counteracting the pro-oxidant effects of Cd.     

Conformation of neuropeptide Y receptor antagonists: structural implications in receptor selectivity

Two NPY analogue peptides, BVD10 (Ile-Asn-Pro-Ile-Tyr-Arg-Leu-Arg-Tyr-OMe) and BVD15 (Ile-Asn-Pro-Ile-Tyr-Arg-Leu-Arg-Tyr-NH(2)) were characterized conformationally by NMR, CD and molecular dynamics simulations. The two peptides exhibit different secondary structure characteristics in trifluoroethanol. BVD10 exhibits a structure with two consecutive beta-turns at Asn2-Pro3-Ile4-Tyr5 and Ile4-Tyr5-Arg6-Leu7. BVD15 exhibits a helical type of structure along with a beta-turn at Asn2-Pro3-Ile4-Tyr5. Molecular modeling studies suggested that the C-terminus Tyr9 is oriented in different directions in the two peptides. The difference in the structures of peptides observed may contribute to the Y(1) selectivity of BVD10 relative to BVD15.     

Disseminated rhinosporidiosis masquerading as soft tissue round cell tumour diagnosed by fine needle aspiration cytology

Rhinosporidium seeberi belongs to the eukaryotic class Mesomycetozoea and causes chronic granulomatous lesions known as rhinosporidiosis. Rhinosporidiosis frequently involves the nasal cavity and nasopharynx through transepithelial invasion. Atypical presentations of this disease at other body sites have been reported, including the subcutis, visceral organs, bones, and genitals. Only a few cases of cutaneous and subcutaneous involvement have been reported to date. This chronic granulomatous condition is known for its recurrence following autoinoculation unless the correct diagnosis and appropriate treatment are given. We describe a case of an immunocompetent adult who had undergone fine needle aspiration cytology (FNAC) of mass-like swellings in the right thigh and right calf at another healthcare centre and had been diagnosed with a small round blue cell tumour. FNAC at our centre confirmed a rare case of rhinosporidiosis that was clinically mimicking a soft tissue neoplasm of the lower extremity, and the erroneous interpretation of the prior cytology studies had resulted in misinterpretation of the individually dispersed pathogenic organisms as individual malignant cells. FNAC of rhinosporidiosis can lead to early diagnosis and prompt treatment of this pathogen when it presents at unanticipated body sites.     

Global asymptotic stability of complex-valued neural networks with additive time-varying delays

In this paper, we extensively study the global asymptotic stability problem of complex-valued neural networks with leakage delay and additive time-varying delays. By constructing a suitable Lyapunov–Krasovskii functional and applying newly developed complex valued integral inequalities, sufficient conditions for the global asymptotic stability of proposed neural networks are established in the form of complex-valued linear matrix inequalities. This linear matrix inequalities are efficiently solved by using standard available numerical packages. Finally, three numerical examples are given to demonstrate the effectiveness of the theoretical results.     

Environmental Response and Genomic Regions Correlated with Rice Root Growth and Yield under Drought in the OryzaSNP Panel across Multiple Study Systems

The rapid progress in rice genotyping must be matched by advances in phenotyping. A better understanding of genetic variation in rice for drought response, root traits, and practical methods for studying them are needed. In this study, the OryzaSNP set (20 diverse genotypes that have been genotyped for SNP markers) was phenotyped in a range of field and container studies to study the diversity of rice root growth and response to drought. Of the root traits measured across more than 20 root experiments, root dry weight showed the most stable genotypic performance across studies. The environment (E) component had the strongest effect on yield and root traits. We identified genomic regions correlated with root dry weight, percent deep roots, maximum root depth, and grain yield based on a correlation analysis with the phenotypes and aus, indica, or japonica introgression regions using the SNP data. Two genomic regions were identified as hot spots in which root traits and grain yield were co-located; on chromosome 1 (39.7–40.7 Mb) and on chromosome 8 (20.3–21.9 Mb). Across experiments, the soil type/ growth medium showed more correlations with plant growth than the container dimensions. Although the correlations among studies and genetic co-location of root traits from a range of study systems points to their potential utility to represent responses in field studies, the best correlations were observed when the two setups had some similar properties. Due to the co-location of the identified genomic regions (from introgression block analysis) with QTL for a number of previously reported root and drought traits, these regions are good candidates for detailed characterization to contribute to understanding rice improvement for response to drought. This study also highlights the utility of characterizing a small set of 20 genotypes for root growth, drought response, and related genomic regions.     

Examining and elucidation of human weight cycle model adopting e-cell simulation system

Cellular rhythms regulate various physiological functions in circadian oscillatory mechanisms. Weight cycling or ‘yo-yo’ dieting is an evitable process in human, because of subsequent loss and regain of body weight due to irregular diet. Human weight cycle (HWC) is the major factor for causing global epidemic diseases in human beings. Understanding the HWC process would provide potent additional knowledge to prevent obesity. However till date, there is no study dealing with examine the HWC model using virtual cell simulation based on system biological approach. Therefore, the present study was designed to develop a computational HWC model, which was simulated using E-cell system v3.0. The developed model has the cyclic feedback reactions of three significant variables (the consecutive cycles of weight loss in continuous food intake (Q) and regain of body weight (P) at highest threshold point of cognitive restraint (R)) which are obtained by mathematical modelling. The dynamic plot results supported that the PQR variables depicted sustained oscillation with reversible modification due to protein diet. By contrast, the virtual model simulation would provide extensive information on HWC, which might provide knowledge to develop HWC linked with obesity pathway. The presents study concludes that optimization of body weight is essential to prevent the obesity based diseases.     

Hydrogen-exchange mass spectrometry for the study of intrinsic disorder in proteins

Amide hydrogen/deuterium exchange detected by mass spectrometry (HXMS) is seeing wider use for the identification of intrinsically disordered parts of proteins. In this review, we discuss examples of how discovery of intrinsically disordered regions and their removal can aid in structure determination, biopharmaceutical quality control, the characterization of how post-translational modifications affect weak structuring of disordered regions, the study of coupled folding and binding, and the characterization of amyloid formation. This article is part of a Special Issue entitled: Mass spectrometry in structural biology.     

Lactobacillus fermentum MCC2759 and MCC2760 Alleviate Inflammation and Intestinal Function in High-Fat Diet-Fed and Streptozotocin-Induced Diabetic Rats

Probiotics and Antimicrobial Proteins - The growing incidence of type 2 diabetes and obesity has become a worldwide crisis with increased socio-economic burden. Changes in lifestyle and food habits...