Study of \u3ci\u3eRickettsia parkeri\u3c/i\u3e Colonization and Proliferation in the Tick Host \u3ci\u3eAmblyomma maculatum\u3c/i\u3e (Acari: Ixodidae)

Amblyomma maculatum (Gulf coast tick) ticks are prevalent across the Atlantic to Gulf Coast region of United States. These ticks are recognized vectors of Rickettsia parkeri, a spotted fever group of Rickettsia (SFGR) known to cause American boutonneuse fever associated with fever and eschar rashes localized to the site of bites. We hypothesized that Rickettsia parkeri colonization and proliferation in the tick vector involve pathogen-symbiont dynamics and tick-pathogen interactions, which influence rickettsial transmission to the victims after tick bites. The rickettsial infection is maintained across the tick life cycle for many generations due to transovarial and transstadial transmission of the pathogen. In the first part, we hypothesized that dynamic interaction among pathogenic R. parkeri and other tick symbionts inside the tick favors the rickettsial pathogen to survive, which multiply and infect vertebrates host upon infestation. We maintained R. parkeri infected and uninfected tick colonies in our lab to study their colonization with I tick. The bacterial loads for R. parkeri, Francisella like endosymbionts and “Candidatus Midichloria mitochondrii” were estimated in both tick colonies during different life stages and within various tick organs that are vital for blood-feeding, reproduction, and disease transmission by using specific qRT-PCR primers. Our results showed that R. parkeri thrives when CMM is present but displaces FLE along the tick life-cycle. In the second part, we hypothesized that tick SECIS binding protein (SBP2) and selenoprotein P (SELENOP) are essential in selenoprotein biosynthesis, and thereby play a role in overall tick redox balance and rickettsial colonization. RNAi assays were employed to specifically silence tick SBP2 and SELENOP. The silencing of SBP2 and SELENOP impaired synthesis of many known selenoproteins except selenophosphate synthetase (SEPHS2) and selenoprotein O (SELENOO). Neither of the genes impaired tick feeding, but SBP2 silencing significantly impacted tick oviposition success and egg hatching. The silencing of SBP2 further impaired rickettsial colonization and reduced transovarial transmission, whereas the SELENOP did not show role in tick feeding success or ovipositioning, but it did impair rickettsial colonization and transovarial transmission. This study provided new avenues of pathogen-symbiont dynamics and tick-pathogen interactions within vectors. Link to thesis - http://aquila.usm.edu/masters_theses/272

Appetite and Satiety Control-Gut Mechanisms

The prevalence of obesity and its comorbidities, particularly type 2 diabetes, cardiovascular and hepatic disease and certain cancers, continues to rise worldwide. Paradoxically, despite an increasingly obesogenic environment, particularly in Western societies, undernutrition is also extremely common. The application of novel, sophisticated techniques, particularly related to imaging and molecular biology, has substantially advanced our understanding of the mechanisms controlling appetite and energy intake. This has led to a redefinition of many concepts, including the relative importance of central versus peripheral mechanisms, recognising that the gastrointestinal (GI) tract, particularly gut hormones, plays a critical role. Given the major advance in knowledge in the field, this Special Issue provides a comprehensive overview of the GI mechanisms underlying the regulation of appetite and energy intake, as a series of definitive reviews by international authorities. The reviews address gut-related mechanisms, including nutrient sensing, gut hormones and GI motility, gut-brain communication, including the roles of the vagus and the modulation of reward perception, the roles of diet and the microbiota, as well as the abnormalities associated with eating disorders, specifically obesity and anorexia of ageing, and the beneficial effects of bariatric surgery. The reviews cover both preclinical research and studies in humans, and are complemented by a number of important original papers

Emerging Paradigms in Insulin Resistance

This book provides a resource for the scientist or medical professional interested in the topic of insulin resistance. With a mix of review and primary data articles, emerging paradigms in insulin resistance are highlighted. The topics are succinctly presented, and distinct viewpoints are represented. An introduction to the Special Issue that provides summaries of the studies included, is provided by the Guest Editor, Dr. Susan Burke, and her colleague at the Pennington Biomedical Research Center, Dr. Jason Collier

Omega-3 Fatty Acids in Health and Disease

The role of major dietary omega-3 fatty acids (Ω-3; α-linolenic acid, eicosapentaenoic acid and docosahexaenoic acid) in human health has generated enormous scientific interest and many controversies in recent years. Due to a growing number of studies with conflicting or even negative clinical results, the former “hype” of Ω-3 thought to be beneficial in many aspects of human health regardless of the physiological and clinical preconditions is now being critically re-evaluated, especially with respect to the potential role of Ω-3 fatty acid supplementation in preventing a variety of diseases and clinical conditions. This critical view reflects the complex interaction of Ω-3 with cell membranes and their integrated proteins mediating signal transduction, transport systems, and other processes. Moreover, Ω-3 are precursors of bioactive metabolites, such as eicosanoids, lipoxins, resolvins, protectins, maresins, and nitrolipids that influence several physiological and pathophysiological processes and their full spectrum of effects are only beginning to be defined. Finally, physiological and pathophysiological conditions as well as concomitant pharmacological treatments may influence the specific and non-specific actions of Ω-3 supplementation. This Special Issue of the Journal of Clinical Medicine will emphasize the role and biological interactions of Ω-3 with regard to cancer, psychiatric disorders, metabolic disorders and nutrition and will also reflect on some basic molecular and cellular mechanisms

Faculty Publications and Creative Works 1998

One of the ways in which we recognize our faculty at the University of New Mexico is through Faculty Publications & Creative Works. An annual publication, it highlights our faculty\u27s scholarly and creative activities and achievements and serves as a compendium of UNM faculty efforts during the 1998 calendar year. Faculty Publications & Creative Works strives to illustrate the depth and breadth of research activities performed throughout our University\u27s laboratories, studios and classrooms. We believe that the communication of individual research is a significant method of sharing concepts and thoughts and ultimately inspiring the birth of new ideas. In support of this, UNM faculty during 1998 produced over 2,457 works, including 1,990 scholarly papers and articles, 69 books, 98 book chapters, 119 reviews, 165 creative works and 16 patents. We are proud of the accomplishments of our faculty which are in part reflected in this book, which illustrates the diversity of intellectual pursuits in support of research and education at the University of New Mexico. Nasir Ahmed, Ph.D. Interim Associate Provost for Research and Dean of Graduate Studie

Carotenoides en agroalimentación y salud

Los carotenoides son compuestos especiales; si bien es común referirse a ellos como pigmentos, lo cierto es que son compuestos de gran versatilidad e importancia en la naturaleza. Más específicamente, son de gran interés en agroalimentación y salud. Así, por ejemplo, son pigmentos naturales y por lo tanto tienen un importante papel en la elección de alimentos por parte de los consumidores. Asimismo, algunos de ellos son precursores de la vitamina A. Sin embargo, que cada vez exista más interés en los carotenoides en este contexto se debe en gran parte a muchos estudios de distinta naturaleza que indican que pueden proporcionar beneficios para la salud. Su interés en alimentación funcional es por lo tanto indudable. En este libro se refleja la experiencia en carotenoides de un gran número de profesionales de la región iberoamericana. En conjunto, se ofrece una visión general de la investigación sobre estos compuestos en agroalimentación y salud. Los autores son miembros de la red IBERCAROT (http://carotenoides.us.es), que tiene entre sus objetivos conformar una red estable y funcional de profesionales que aúnen esfuerzos en pos de identificar nuevas fuentes de carotenoides de interés nutricional, mejorar su producción y aumentar el valor de los productos que los contengan

Fruit Metabolism and Metabolomics

Over the past ten years, metabolomics strategies have allowed the relative or absolute quantitation of metabolite levels for the study of various biological questions in plant sciences. For fruit studies, in particular, they have participated in the identification of the genes underpinning fruit development and ripening. This book proposes examples of the current use of metabolomics studies of fruit for basic research or practical applications. It includes articles about several tropical and temperate fruit species. The studies concern fruit biochemical phenotyping, fruit metabolism during development and after harvest, including primary and specialized metabolisms, or bioactive compounds involved in fruit growth and environmental responses. The analytical strategies used are based mostly on liquid or gas chromatography coupled with mass spectrometry, but also on nuclear magnetic resonance and near-infrared spectroscopy. The effect of genotype, stages of development, or fruit tissue type on metabolomic profiles and corresponding metabolism regulations are addressed for fruit metabolism studies. The interest in combining other omics with metabolomics is also exemplified

The Potential of Dietary Antioxidants

Oxidative stress causes chronic diseases such as cardiovascular disease, cancer, Alzheimer, chronic obstructive pulmonary, and neurodegenerative pathologies. Antioxidant systems defend human cells from free radicals. They act by stopping free radicals, decreasing their development, and quenching the formed ROS and RNS. The antioxidant molecules are classified into primary and secondary defense molecules. The primary antioxidant molecules (i.e., vitamins C and E, ubiquinone, and glutathione) reduce oxidation effects by moving a proton to the free radical species or electron donors, or by terminating the chain reactions The secondary antioxidants (i.e., N-acetyl cysteine and lipoic acid) act as cofactors for some enzyme systems or neutralize the production of free radicals by transition metals. This work comprises original research papers and reviews on antioxidant molecules in food, the agricultural practices that maximize their levels in plants, the potential preventive effects of selected classes of antioxidant molecules, their potential use in functional foods, and the pharmaceutical delivery systems that maximize their potential activity when used as supplements