Nicotine, Tobacco Use, and the 55th Nebraska Symposium on Motivation

Tobacco use is a worldwide health problem. As so well stated by Mackay and Ericksen (2002), “No other consumer product is as dangerous, or kills as many people. Tobacco kills more than AIDS, legal drugs, illegal drugs, road accidents, murder, and suicide combined” (p. 36). Imagine the lives saved, and the amount of pain, emotional suffering, and fiscal burden alleviated, if we could devise approaches that helped current tobacco users quit and remain abstinent, and prevented new smokers from emerging. Although these idealistic goals are worth pursuing, improving cessation rates by only a small fraction, or making small gains in preventing people from experimenting with tobacco, would nevertheless translate into significant improvement in the health and well-being of countless thousands worldwide as well as financial savings to employers, government institutions, and the heath care system. Even such small, incremental steps require a concerted and coordinated effort by basic scientists, clinical researchers and practitioners, and policy makers to discover the basis of tobacco dependence and apply that knowledge to the implementation of prevention policies and smoking cessation aids. This year\u27s Nebraska Symposium on Motivation was devoted to research on the drug that is widely believed to form the basis of tobacco use and dependence, nicotine

Potential role of wildlife in the USA in the event of a foot-and-mouth disease virus incursion

Foot-and-mouth disease (FMD) is caused by foot-and-mouth disease virus (FMDV) which affects domestic and wild cloven-hoofed species. The FMD-free status of the USA and the tremendous economic impact of a virus incursion motivated the development of this evaluation of the potential role of wildlife in the event of a virus introduction. Additionally, this manuscript contains a summary of US vulnerabilities for viral incursion and persistence which focuses specifically on the possible role of wildlife. The legal movement of susceptible live animals, animal products, by-products and animal feed containing animal products pose a risk of virus introduction and spread. Additionally, the illegal movement of FMD-susceptible animals and their products and an act of bioterrorism present additional routes where FMDV could be introduced to the USA. Therefore, robust surveillance and rapid diagnostics in the face of a possible introduction are essential for detecting and controlling FMD as quickly as possible. Wildlife species and feral pigs present an added complexity in the case of FMDV introduction as they are typically not closely monitored or managed and there are significant logistical concerns pertaining to disease surveillance and control in these populations. Recommendations highlight the need to address existing knowledge gaps relative to the potential role of wildlife in FMDV introduction events

Interoceptive conditioning with nicotine using extinction and re-extinction to assess stimulus similarity with bupropion

Bupropion is an atypical antidepressant that increases long-term quit rates of tobacco smokers. A better understanding of the relation between nicotine and this first-line medication may provide insight into improving treatment. For all experiments, rats first had nicotine (0.4 mg base/kg) and saline session intermixed; intermittent access to sucrose only occurred on nicotine session. Nicotine in this protocol comes to differentially control “anticipatory” dipper entries. To more closely examine the overlap in the interoceptive stimulus effects of nicotine and bupropion, we assessed whether subsequent prolonged and repeated non-reinforced (extinction) sessions with the bupropion stimulus could weaken responding to nicotine (i.e., transfer of extinction). We also examined whether retraining the discrimination after initial extinction and then conducting extinction again (i.e., re-extinction) with bupropion would affect responding. We found that bupropion (20 and 30 mg/kg) fully substituted for the nicotine stimulus in repeated 20-min extinction sessions. The extent of substitution in extinction did not necessarily predict performance in the transfer test (e.g., nicotine responding unchanged after extinction with 20 mg/kg bupropion). Generalization of extinction back to nicotine was not seen with 20 mg/kg bupropion even after increasing the number of extinction session from 6 to 24. Finally, there was evidence that learning in the initial extinction phase was retained in the re-extinction phase for nicotine and bupropion. These findings indicate that learning involving the nicotine stimuli are complex and that assessment approach for stimulus similarity changes conclusions regarding substitution by bupropion. Further research will be needed to identify whether such differences may be related to different facets of nicotine dependence and/or its treatment

Interoceptive conditioning with nicotine using extinction and re-extinction to assess stimulus similarity with bupropion

Bupropion is an atypical antidepressant that increases long-term quit rates of tobacco smokers. A better understanding of the relation between nicotine and this first-line medication may provide insight into improving treatment. For all experiments, rats first had nicotine (0.4 mg base/kg) and saline session intermixed; intermittent access to sucrose only occurred on nicotine session. Nicotine in this protocol comes to differentially control “anticipatory” dipper entries. To more closely examine the overlap in the interoceptive stimulus effects of nicotine and bupropion, we assessed whether subsequent prolonged and repeated non-reinforced (extinction) sessions with the bupropion stimulus could weaken responding to nicotine (i.e., transfer of extinction). We also examined whether retraining the discrimination after initial extinction and then conducting extinction again (i.e., re-extinction) with bupropion would affect responding. We found that bupropion (20 and 30 mg/kg) fully substituted for the nicotine stimulus in repeated 20-min extinction sessions. The extent of substitution in extinction did not necessarily predict performance in the transfer test (e.g., nicotine responding unchanged after extinction with 20 mg/kg bupropion). Generalization of extinction back to nicotine was not seen with 20 mg/kg bupropion even after increasing the number of extinction session from 6 to 24. Finally, there was evidence that learning in the initial extinction phase was retained in the re-extinction phase for nicotine and bupropion. These findings indicate that learning involving the nicotine stimuli are complex and that assessment approach for stimulus similarity changes conclusions regarding substitution by bupropion. Further research will be needed to identify whether such differences may be related to different facets of nicotine dependence and/or its treatment

Ore paragenesis of the Tajo Vein, Paramillos de Uspallata ore deposit, Mendoza Province, Argentina

La Veta Tajo forma par te del yacimiento Paramillos de Uspallata (32°28’29.6”S; 69°08’46”O), ubicado en la Precordillera Occidental de la provincia de Mendoza. Este yacimiento está formado por un conjunto de vetas con mineralización de Pb-Zn-Ag hospedadas en basaltos triásico-jurásicos y en sedimentitas triásicas. Los estudios mineraló- gicos (microscopía óptica convencional y SEM-EDX) realizados sobre muestras provenientes de la veta Tajo permitieron determinar que la paragénesis de mena está compuesta por galena argentífera, esfalerita, calcopirita, tetraedrita, freibergita, boulangerita, owyheeita, pirita, arsenopirita y marcasita así como la existencia de dos pulsos de mineralización, un primer pulso principalmente de Pb-Zn-Ag-(Cu) en ganga carbonática y un segundo pulso estéril en ganga de cuarzo. Por otra parte los análisis de química mineral permitieron determinar la composición de los minerales de mena y de esta forma establecer cuáles son aquellos portadores de Ag.The Tajo Vein is par t of the Paramillos de Uspallata ore deposit (32°28’29.6”S; 69°08’46”W) that is located in the Western Precordillera of Mendoza Province. This ore deposit consists of Pb-Zn-Ag veins hosted by Triassic-Jurassic basalts and Triassic sedimentary rocks. Mineralogical studies (optical microscopy and SEM-EDX analyses) carried out on samples from the Tajo Vein allowed the identification of an ore paragenesis consisting of Ag-galena, sphalerite, chalcopyrite, tetrahedrite, freibergite, boulangerite, owyheeite, pyrite, arsenopyrite and marcasite, occurring in two mineralization stages, the first consisting of Pb-Zn-Ag-(Cu) mineralization with a carbonate gangue and the barren second one with a quartz gangue. Chemical analyses allowed to determine the composition of the ore minerals and the Ag-bearing phases.Fil: Carrasquero, S. I.. Universidad Nacional de la Plata. Facultad de Ciencias Naturales y Museo. Instituto de Recursos Minerales. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto de Recursos Minerales; ArgentinaFil: Rubinstein, Nora Alicia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geociencias Basicas, Aplicadas y Ambientales de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geociencias Basicas, Aplicadas y Ambientales de Buenos Aires; ArgentinaFil: Bevins, R. E.. National Museum of Wales; Reino Unid

Intestinal antimicrobial gene expression: impact of micronutrients in malnourished adults during a randomized trial.

BACKGROUND: Because both micronutrients and antimicrobial peptides protect against diarrhea, we looked for an effect on intestinal antimicrobial peptide gene expression during a randomized controlled trial of multiple micronutrient (MM) supplementation. METHODS: Consenting adults (n=287) in Lusaka, Zambia, were randomized to receive a daily MM supplement or placebo and were followed up for 3.3 years, with a crossover after 2 years. Intestinal biopsy samples were obtained at annual intervals, and messenger RNA of the intestinal antimicrobial peptides human alpha defensin (HD) 5, HD6, human beta-defensin (hBD) 1, hBD2, and LL-37 were quantified by real-time reverse-transcriptase polymerase chain reaction. Samples were also obtained during diarrhea episodes and after convalescence. RESULTS: There was no effect overall of treatment allocation. However, in malnourished adults (body mass index < or =18.5), HD5 mRNA was increased by 0.8 log transcripts/microg total RNA in MM recipients, compared with HD5 mRNA in placebo recipients (P=.007). During diarrhea, HD5 expression was reduced by 0.8 log transcripts in placebo recipients (P=.02) but was not reduced in MM recipients, nor was it reduced after the crossover. Correlations between HD5 and nutritional status were found that were sex-specific but not explained by serum leptin or adiponectin concentrations. CONCLUSIONS: Micronutrient supplementation was associated with up-regulation of HD5 only in malnourished adults. Interactions between antimicrobial gene expression and nutritional status may help to explain the increased risk of infection in individuals with malnutrition

Long-distance landscapes: from quarries to monument at Stonehenge.

Stonehenge is famous for the distances moved by its stones, both sarsens and bluestones. In particular, the bluestones have their geological origins in West Wales, 225km away. Recent excavations at two of these bluestone sources – one for rhyolite and one for spotted dolerite – have identified evidence of megalith quarrying around 3000 BC, when Stonehenge’s first stage was constructed. This remarkable movement of bluestones from Wales coincided with a decline in regional cultural distinctions between west and east, suggesting that building Stonehenge may have served to unify the Neolithic populations of Britain

An agent-based movement model to assess the impact of landscape fragmentation on disease transmission

Landscape changes can result in habitat fragmentation and reduced landscape connectivity, limiting the ability of animals to move across space and altering infectious disease dynamics in wildlife. In this study, we develop and implement an agent-based model to assess the impacts of animal movement behavior and landscape structure on disease dynamics. We model a susceptible/infective disease state system applicable to the transmission of feline immunodeficiency virus in bobcats in the urbanized landscape of coastal southern California. Our agent-based model incorporates animal movement behavior, pathogen prevalence, transmission probability, and habitat fragmentation to evaluate how these variables influence disease spread in urbanizing landscapes. We performed a sensitivity analysis by simulating the system under 4200 different combinations of model parameters and evaluating disease transmission outcomes. Our model reveals that host movement behavior and response to landscape features play a pivotal role in determining how habitat fragmentation influences disease dynamics. Importantly, interactions among habitat fragmentation and movement had non-linear and counter-intuitive effects on disease transmission. For example, the model predicts that an intermediate level of non-habitat permeability and directionality will result in the highest rates of between-patch disease transmission. Agent-based models serve as computational laboratories that provide a powerful approach for quantitatively and visually exploring the role of animal behavior and anthropogenic landscape change on contacts among agents and the spread of disease. Such questions are challenging to study empirically given that it is difficult or impossible to experimentally manipulate actual landscapes and the animals and pathogens that move through them. Modeling the relationship between habitat fragmentation, animal movement behavior, and disease spread will improve understanding of the spread of potentially destructive pathogens through wildlife populations, as well as domestic animals and humans

The Effect of Oral Contraceptive Pill Use on Knee Joint Laxity in Women

Schultz et al. (2004) demonstrated that 63% of the change in knee joint laxity (KJL) during a menstrual cycle was due to associated fluctuations in sex hormone levels. Use of oral contraceptives modulates the fluctuation of sex hormone levels during the menstrual cycle and thus may reduce fluctuation in KJL PURPOSE: Given that increased KJL is a known risk factor for sustaining knee injuries, the purpose of this study was to examine the effect of oral contraceptive use on KJL during the follicular, ovulation, and luteal phases of the menstrual cycle. METHODS: Sixty college-age women were screened for participation and fourteen (20.07±1.21 years, 163.05± 9.70, and 66.81± 12.32 kg) met the inclusion criteria, provided informed consent, and participated in the study. Based on screening questionnaires, participants were sorted into groups, oral contraceptive users (OC) and non-users (NOC). Each participant’s KJL was measured on six occasions, five days apart. KJL was measured using a KT-1000 Knee Arthrometer at 133 N. Measurements on days 1-7, 11-14, and 19-22 were used for data analysis to correspond with the three phases of the menstrual cycle. A 2x3 (group x phase) mixed model ANOVA was used to compare KJL between groups and across the three phases of the menstrual cycle. RESULTS: KJL are reported in Table 1. Group and phase did not interact to affect KJL (F(2,24)=1.92, p=0.17). KJL did not differ between OC and NOC users across the menstrual cycle (F(1,12)=0.07, p=0.80), and was not different between any phase of the menstrual cycle (F(2,24)=0.14, p=0.87). However, given that the spike in estradiol associated with the ovulation phase has been suggested to affect ligament laxity, a comparison between groups during this phase was conducted. Though KJL was larger for NOC than OC, the results of a one-tailed independent t-test suggest that this difference was not statistically significantly (t(12)= 1.72, p = 0.06). However, this difference was characterized by a large effect size (Cohen d= 0.92) suggesting that NOC users experience more KJL during the ovulation phase than OC users. CONCLUSION: The results of the study indicate that OC may play a role in KJL. However, with limited statistical power of these analyses, additional data are needed to fully assess this effect

Nicotine, Tobacco Use, and the 55th Nebraska Symposium on Motivation

Tobacco use is a worldwide health problem. As so well stated by Mackay and Ericksen (2002), “No other consumer product is as dangerous, or kills as many people. Tobacco kills more than AIDS, legal drugs, illegal drugs, road accidents, murder, and suicide combined” (p. 36). Imagine the lives saved, and the amount of pain, emotional suffering, and fiscal burden alleviated, if we could devise approaches that helped current tobacco users quit and remain abstinent, and prevented new smokers from emerging. Although these idealistic goals are worth pursuing, improving cessation rates by only a small fraction, or making small gains in preventing people from experimenting with tobacco, would nevertheless translate into significant improvement in the health and well-being of countless thousands worldwide as well as financial savings to employers, government institutions, and the heath care system. Even such small, incremental steps require a concerted and coordinated effort by basic scientists, clinical researchers and practitioners, and policy makers to discover the basis of tobacco dependence and apply that knowledge to the implementation of prevention policies and smoking cessation aids. This year\u27s Nebraska Symposium on Motivation was devoted to research on the drug that is widely believed to form the basis of tobacco use and dependence, nicotine