bluuebunny/crossref_metadata_2025 huggingface dataset:
Lipoprotein Lipase in the Brain and Nervous System
Authors: Wang Hong , Eckel Robert H.
Published: June 2012

Lipoprotein lipase (LPL) is rate limiting in the provision of triglyceride-rich lipoprotein-derived lipids into tissues. LPL is also present in the brain, where its function has remained elusive. Recent evidence implicates a role of LPL in the brain in two processes: (a) the regulation of energy balance and body weight and (b) cognition. Mice with neuron-specific deletion of LPL have increases in food intake that lead to obesity, and then reductions in energy expenditure that further contribute to and sustain the phenotype. In other mice with LPL deficiency rescued from neonatal lethality by somatic gene transfer wherein LPL in the brain remains absent, altered cognition ensues. Taking into consideration data that associate LPL mutations with Alzheimer's disease, a role for LPL in learning and memory seems likely. Overall, the time is ripe for new insights into how LPL-mediated lipoprotein metabolism in the brain impacts CNS processes and systems biology.
Modeling Metabolic Adaptations and Energy Regulation in Humans
Authors: Hall Kevin D.
Published: June 2012

Mathematical modeling of human energy regulation and body weight change has recently reached the level of sophistication required for accurate predictions. Mathematical models are beginning to provide a quantitative framework for integrating experimental data in humans and thereby help us better understand the dynamic imbalances of energy and macronutrients that give rise to changes in body weight and composition. This review provides an overview of the various approaches that have been used to model body weight dynamics and energy regulation in humans, highlights several insights that these models have provided, and suggests how mathematical models can serve as a guide for future experimental research.
New Roles of HDL in Inflammation and Hematopoiesis
Authors: Zhu Xuewei , Parks John S.
Published: June 2012

High-density lipoprotein (HDL) levels are inversely associated with coronary heart disease due to HDL's ability to transport excess cholesterol in arterial macrophages to the liver for excretion [i.e., reverse cholesterol transport (RCT)]. However, recent advances highlight additional atheroprotective roles for HDL beyond bulk cholesterol removal from cells through RCT. By promoting cellular free cholesterol (FC) efflux, HDL and its apolipoproteins (apoA-I and apoE) decrease plasma membrane FC and lipid raft content in immune and hematopoietic stem cells, decreasing inflammatory and cell proliferation signaling pathways. HDL and apoA-I also dampen inflammatory signaling pathways independent of cellular FC efflux. In addition, HDL lipid and protein cargo provide protection against parasitic and bacterial infection, endothelial damage, and oxidant toxicity. Here, current knowledge is reviewed regarding the role of HDL and its apolipoproteins in regulating cellular cholesterol homeostasis, highlighting recent advances on novel functions and mechanisms by which HDLs regulate inflammation and hematopoiesis.
Obesity in Cancer Survival
Authors: Parekh Niyati , Chandran Urmila , Bandera Elisa V.
Published: June 2012

Although obesity is a well-known risk factor for several cancers, its role on cancer survival is poorly understood. We conducted a systematic literature review to assess the current evidence evaluating the impact of body adiposity on the prognosis of the three most common obesity-related cancers: prostate, colorectal, and breast. We included 33 studies of breast cancer, six studies of prostate cancer, and eight studies of colo-rectal cancer. We note that the evidence overrepresents breast cancer survivorship research and is sparse for prostate and colorectal cancers. Overall, most studies support a relationship between body adiposity and site-specific mortality or cancer progression. However, most of the research was not specifically designed to study these outcomes and, therefore, several methodological issues should be considered before integrating their results to draw conclusions. Further research is urgently warranted to assess the long-term impact of obesity among the growing population of cancer survivors.
An Unexpected Life in Nutrition
Authors: Nesheim Malden C.
Published: June 2012

In this biographical article, I describe the evolution of my career in nutrition from an early period as an animal nutritionist interested in amino acid metabolism and genetic variation in nutrient requirements to an involvement in human nutrition and international public health. The career changes were in some respects a mirror of the evolution of nutritional science in my lifetime. I spent my entire career at Cornell University in what I think of as three distinct phases. As a researcher and teacher in the Poultry Science Department, I was able to do research in animal nutrition and witness the rapid industrialization of the production of poultry meat and eggs, helped by the findings of the era of nutrient discovery in nutritional science. Later I had the opportunity to lead the reorganization of human nutrition at Cornell during a period when research in nutritional science turned away from identifying new nutrients and became increasingly concerned with the roles of diet and chronic disease. During this period my research focus evolved as I became interested in aspects of international nutrition problems, particularly the influence of parasitic infections on child health and nutrition. I also became involved nationally in nutrition issues through participation in organizations such as the National Nutrition Consortium, the Food and Nutrition Board, and National Institutes of Health study sections at a time of great ferment in nutrition about the relationship of dietary patterns to health. Finally, I became provost of Cornell University and involved in the administration of a major research university. I describe my career in the context of my origins and early education springing from life on a sustainable family farm in rural Illinois.
Resolvins: Anti-Inflammatory and Proresolving Mediators Derived from Omega-3 Polyunsaturated Fatty Acids
Authors: Zhang Michael J. , Spite Matthew
Published: June 2012

Omega-3 polyunsaturated fatty acids (PUFAs) are essential to health, and deficiencies in these PUFAs are linked to chronic disease. Although important insights into the diverse biological roles of PUFAs have been made, the mechanistic basis underlying their protective actions is still emerging. Studies over the past decade have elucidated that omega-3 PUFAs are enzymatically converted into bioactive autacoids that have inflammation-resolving properties. Among these, resolvins have emerged as an important family that has potent and stereospecific immunomodulatory roles, elucidation of which has contributed to a growing body of literature demonstrating that resolution of acute inflammation is an active process. In addition to their direct interactions with immune cells, resolvins have effects on nonimmune cells as well, suggesting a much broader role in biological systems than originally appreciated. In this review, we describe the endogenous biosynthesis and immunomodulatory actions of resolvins and highlight their emerging roles in health and disease.
Selenoproteins and Cancer Prevention
Authors: Davis Cindy D. , Tsuji Petra A. , Milner John A.
Published: June 2012

The discovery of multiple selenoproteins has raised tantalizing questions about their role in maintaining normal cellular function. Unfortunately, many of these remain inadequately investigated. While they have a role in maintaining redox balance, other functions are becoming increasingly recognized. As the roles of these selenoproteins are further characterized, a better understanding of the true physiological significance of this trace element will arise. This knowledge will be essential in defining optimum intakes to achieve cellular homeostasis in order to optimize health, including a reduction in cancer, for diverse populations. Human variation in the response to selenium likely reflects significant interactions between the type and amounts of selenium consumed with the genome and a host of environmental factors including the totality of the diet, as discussed in this review.
The Role of Vitamin D in Pregnancy and Lactation: Insights from Animal Models and Clinical Studies
Authors: Kovacs Christopher S.
Published: June 2012

Maternal adaptations during pregnancy and lactation appear to provide calcium to fetus and neonate without relying on vitamin D or calcitriol. Consequently, the blood calcium, calciotropic hormones, and skeleton appear normal at birth in the offspring of mothers who are severely vitamin D deficient or who lack calcitriol or its receptor. It remains unclear whether skeletal or extraskeletal problems will develop postnatally from exposure to vitamin D deficiency in utero. During the neonatal period, calcitriol-stimulated intestinal calcium absorption becomes the dominant mechanism of calcium delivery. The vitamin D–deficient neonate is at risk to develop hypocalcemia, rickets, and possibly extraskeletal disorders (e.g., type 1 diabetes). Breastfed babies are at higher risk of vitamin D deficiency because normally little vitamin D or 25-hydroxyvitamin D passes into breast milk. Dosing recommendations during pregnancy and lactation should ensure that the baby is born vitamin D sufficient and maintained that way during infancy and beyond.
Toward a Comparative Sociology of Valuation and Evaluation
Authors: Lamont Michèle
Published: June 2012

This review discusses North American and European research from the sociology of valuation and evaluation (SVE), a research topic that has attracted considerable attention in recent years. The goal is to bring various bodies of work into conversation with one another in order to stimulate more cumulative theory building. This is accomplished by focusing on (a) subprocesses such as categorization and legitimation, (b) the conditions that sustain heterarchies, and (c) valuation and evaluative practices. The article reviews these literatures and provides directions for a future research agenda.
Economic Insecurity and Social Stratification
Authors: Western Bruce , Bloome Deirdre , Sosnaud Benjamin , Tach Laura
Published: June 2012

Economic insecurity describes the risk of economic loss faced by workers and households as they encounter the unpredictable events of social life. Our review suggests a four-part framework for studying the distribution and trends in these economic risks. First, a focus on households rather than workers captures the microlevel risk pooling that can smooth income flows and stabilize economic well-being. Second, insecurity is related to income volatility and the risk of downward mobility into poverty. Third, adverse events such as unemployment, family dissolution, or poor health commonly trigger income losses. Fourth, the effects of adverse events are mitigated by insurance relationships provided by government programs, employer benefits, and the informal support of families. Empirical research in these areas reveals high levels of economic insecurity among low-income households and suggests an increase in economic insecurity with the growth in economic inequality in the United States.
Race Relations Within the US Military
Authors: Burk James , Espinoza Evelyn
Published: June 2012

Sociologists now often say that the US military is a model of good race relations. Although there is no denying progress made in military race relations, especially since establishment of the all-volunteer force, this review challenges that comfortable claim as research done over the past two decades supports it only in part. Instead, we conclude that disparities in military allocations of goods and burdens sometimes disadvantage racial minorities. This conclusion rests on a review of institutional analyses in five arenas to which researchers have paid close attention: racial patterns in enlistment, officer promotion rates, administration of military justice, risk of death in combat, and health care for wounded soldiers. Although not a direct or intended result of military policy and practice, in three of five cases there was evidence of racial bias and institutional racism. Further work is needed to identify mechanisms through which the bias and racism arose.
The Race Discrimination System
Authors: Reskin Barbara
Published: June 2012

To understand the persistence of racial disparities across multiple domains (e.g., residential location, schooling, employment, health, housing, credit, and justice) and to develop effective remedies, we must recognize that these domains are reciprocally related and comprise an integrated system. The limited long-run success of government social policies to advance racial justice is due in part to the ad hoc nature of policy responses to various forms of racial discrimination. Drawing on a systems perspective, I show that race discrimination is a system whose emergent properties reinforce the effects of their components. The emergent property of a system of race-linked disparities is über discrimination—a meta-level phenomenon that shapes our culture, cognitions, and institutions, thereby distorting whether and how we perceive and make sense of racial disparities. Viewing within-domain disparities as part of a discrimination system requires better-specified analytic models. While the existence of an emergent system of über discrimination increases the difficulty of eliminating racial disparities, a systems perspective points to strategies to attack that system. These include identifying and intervening at leverage points, implementing interventions to operate simultaneously across subsystems, isolating subsystems from the larger discrimination system, and directly challenging the processes through which emergent discrimination strengthens within-subsystem disparities.
Outsourcing Social Transformation: Development NGOs as Organizations
Authors: Watkins Susan Cotts , Swidler Ann , Hannan Thomas
Published: June 2012

The literature on development nongovernmental organizations (NGOs) envisions an alternative form of social organization, one that is more altruistic, more cooperative, and less hierarchical than governments and for-profit organizations. We engage with the literature on quite different terms: NGOs and their donors are organizations, and much of what is distinctive about them as organizations derives from the special uncertainties they face due to the environments in which they operate, the goals they pursue, and the social and material technologies they employ. We conclude that there are unexplored issues in the literature on development NGOs that sociologists, with their toolkit of theories and practices, are uniquely qualified to address.
Making a Place for Space: Spatial Thinking in Social Science
Authors: Logan John R.
Published: June 2012

New technologies and multilevel data sets that include geographic identifiers have heightened sociologists' interest in spatial analysis. I review several of the key concepts, measures, and methods that are brought into play in this work and offer examples of their application in a variety of substantive fields. I argue that the most effective use of the new tools requires greater emphasis on spatial thinking. A device as simple as an illustrative map requires some understanding of how people respond to visual cues; models as complex as hierarchical linear modeling with spatial lags require thoughtful measurement decisions and raise questions about what a spatial effect represents.
The Future of Historical Family Demography
Authors: Ruggles Steven
Published: June 2012

An explosion of new data sources describing historical family composition is opening unprecedented opportunities for discovery and analysis. The new data will allow comparative multilevel analysis of spatial patterns and will support studies of the transformation of living arrangements over the past 200 years. Using measurement methods that assess family choices at the individual level and analytic strategies that assess variations across space and time, we can dissect the decline of patriarchal family forms in the developed world and place Northwest Europe and North America in global comparative context.
Urbanization and the Southern United States
Authors: Lloyd Richard
Published: June 2012

Cities in the Southern United States have experienced dynamic economic and population growth over the past half-century, challenging existing paradigms of urban form, race relations, social movements, and immigration. This review shows how the timing of Southern urbanization—much later than in the Northeast and Midwest—has contributed to Southern cities' distinctive spatial patterns and political and economic structures. Southern cities were crucial to regional transformation, including the Civil Rights Movement and the end of one-party rule in the South. Moreover, Southern cities exemplify key trends of the contemporary political economy: a new relationship to regional industrialization, new forms of entrepreneurial governance, flexible labor markets, the importance of finance and producer services, and “new destination” immigration. I conclude by examining two Southern cities for their relevance to central themes in contemporary social research: Atlanta for the study of the African American experience and New Orleans for the sociology of catastrophe.
The Sociology of Elites
Authors: Rahman Khan Shamus
Published: June 2012

Elites are those with vastly disproportionate control over or access to a resource. We can understand this as a position that a social actor occupies, or we can imagine such resources as a possession of an actor. The study of elites is the study of power and inequality, from above. It involves looking at the distribution of social resources, which can include economic, social, cultural, political, or knowledge capital. It also means exploring the role of institutions such as schools, families, and clubs in how such resources are organized and distributed. Over the past decade, particularly as social power and economic rewards have become increasingly concentrated in the hands of the few, elite sociology has experienced a revival. Empirical observations of these phenomena point to the changing character of American inequality.
Instrumental Variables in Sociology and the Social Sciences
Authors: Bollen Kenneth A.
Published: June 2012

Instrumental variable (IV) methods provide a powerful but underutilized tool to address many common problems with observational sociological data. Key to their successful use is having IVs that are uncorrelated with an equation's disturbance and that are sufficiently strongly related to the problematic endogenous covariates. This review briefly defines IVs, summarizes their origins, and describes their use in multiple regression, simultaneous equation models, factor analysis, latent variable structural equation models, and limited dependent variable models. It defines and contrasts three methods of selecting IVs: auxiliary instrumental variable, model implied instrumental variable, and randomized instrumental variable. It provides overidentification tests and weak IV diagnostics as methods to evaluate the quality of IVs. I review the use of IVs in models that assume heterogeneous causal effects. Another section summarizes the use of IVs in contemporary sociological publications. The conclusion suggests ways to improve the use of IVs and suggests that there are many areas in which IVs could be profitably used in sociological research.
The Arc of Neoliberalism
Authors: Centeno Miguel A. , Cohen Joseph N.
Published: June 2012

For three decades, neoliberalism dominated the global political economy. Defined as an explicit preference for private over public control, neoliberalism represented a dramatic break from postwar policies. This article examines the historical development of neoliberalism through three perspectives: as an economic policy, as an expression of political power, and as an ideational hegemony. We reject the notion of neoliberal inevitability and suggest how it came to dominate all other possible alternatives. The review emphasizes the critical importance of political preferences and influences as well as the central role ideas played in defining policy paradigms.
Elevated lipopolysaccharide in the colon evokes intestinal inflammation, aggravated in immune modulator-impaired mice
Authors: Im Eunok , Riegler Franz Martin , Pothoulakis Charalabos , Rhee Sang Hoon
Published: June 2012

Frequency of gram-negative bacteria is markedly enhanced in inflamed gut, leading to augmented LPS in the intestine. Although LPS in the intestine is considered harmless and, rather, provides protective effects against epithelial injury, it has been suggested that LPS causes intestinal inflammation, such as necrotizing enterocolitis. Therefore, direct effects of LPS in the intestine remain to be studied. In this study, we examine the effect of LPS in the colon of mice instilled with LPS by rectal enema. We found that augmented LPS on the luminal side of the colon elicited inflammation in the small intestine remotely, not in the colon; this inflammation was characterized by body weight loss, increased fluid secretion, enhanced inflammatory cytokine production, and epithelial damage. In contrast to the inflamed small intestine induced by colonic LPS, the colonic epithelium did not exhibit histological tissue damage or inflammatory lesions, although intracolonic LPS treatment elicited inflammatory cytokine gene expression in the colon tissues. Moreover, we found that intracolonic LPS treatment substantially decreased the frequency of immune-suppressive regulatory T cells (CD4+/CD25+and CD4+/Foxp3+). We were intrigued to find that LPS-promoted intestinal inflammation is exacerbated in immune modulator-impaired IL-10−/−and Rag-1−/−mice. In conclusion, our results provide evidence that elevated LPS in the colon is able to cause intestinal inflammation and, therefore, suggest a physiological explanation for the importance of maintaining the balance between gram-negative and gram-positive bacteria in the intestine to maintain homeostasis in the gut.
Circadian rhythms of gastrointestinal function are regulated by both central and peripheral oscillators
Authors: Malloy Jaclyn N. , Paulose Jiffin K. , Li Ye , Cassone Vincent M.
Published: June 2012

Circadian clocks are responsible for daily rhythms in a wide array of processes, including gastrointestinal (GI) function. These are vital for normal digestive rhythms and overall health. Previous studies demonstrated circadian clocks within the cells of GI tissue. The present study examines the roles played by the suprachiasmatic nuclei (SCN), master circadian pacemaker for overt circadian rhythms, and the sympathetic nervous system in regulation of circadian GI rhythms in the mouse Mus musculus . Surgical ablation of the SCN abolishes circadian locomotor, feeding, and stool output rhythms when animals are presented with food ad libitum, while restricted feeding reestablishes these rhythms temporarily. In intact mice, chemical sympathectomy with 6-hydroxydopamine has no effect on feeding and locomotor rhythmicity in light-dark cycles or constant darkness but attenuates stool weight and stool number rhythms. Again, however, restricted feeding reestablishes rhythms in locomotor activity, feeding, and stool output rhythms. Ex vivo, intestinal tissue from PER2::LUC transgenic mice expresses circadian rhythms of luciferase bioluminescence. Chemical sympathectomy has little effect on these rhythms, but timed administration of the β-adrenergic agonist isoproterenol causes a phase-dependent shift in PERIOD2 expression rhythms. Collectively, the data suggest that the SCN are required to maintain feeding, locomotor, and stool output rhythms during ad libitum conditions, acting at least in part through daily activation of sympathetic activity. Even so, this input is not necessary for entrainment to timed feeding, which may be the province of oscillators within the intestines themselves or other components of the GI system.
Hepatocyte-specific ablation of spermine/spermidine-N1-acetyltransferase gene reduces the severity of CCl4-induced acute liver injury
Authors: Zahedi Kamyar , Barone Sharon L. , Xu Jie , Steinbergs Nora , Schuster Rebecca , Lentsch Alex B. , Amlal Hassane , Wang Jiang , Casero Robert A. , Soleimani Manoocher
Published: June 2012

Activation of spermine/spermidine- N1-acetyltransferase (SSAT) leads to DNA damage and growth arrest in mammalian cells, and its ablation reduces the severity of ischemic and endotoxic injuries. Here we have examined the role of SSAT in the pathogenesis of toxic liver injury caused by carbon tetrachloride (CCl4). The expression and activity of SSAT increase in the liver subsequent to CCl4administration. Furthermore, the early liver injury after CCl4treatment was significantly attenuated in hepatocyte-specific SSAT knockout mice (Hep-SSAT-Cko) compared with wild-type (WT) mice as determined by the reduced serum alanine aminotransferase levels, decreased hepatic lipid peroxidation, and less severe liver damage. Cytochrome P450 2e1 levels remained comparable in both genotypes, suggesting that SSAT deficiency does not affect the metabolism of CCl4. Hepatocyte-specific deficiency of SSAT also modulated the induction of cytokines involved in inflammation and repair as well as leukocyte infiltration. In addition, Noxa and activated caspase 3 levels were elevated in the livers of WT compared with Hep-SSAT-Cko mice. Interestingly, the onset of cell proliferation was significantly more robust in the WT compared with Hep-SSAT Cko mice. The inhibition of polyamine oxidases protected the animals against CCl4-induced liver injury. Our studies suggest that while the abrogation of polyamine back conversion or inhibition of polyamine oxidation attenuate the early injury, they may delay the onset of hepatic regeneration.
Myofascial force transmission between the human soleus and gastrocnemius muscles during passive knee motion
Authors: Tian Maoyi , Herbert Robert D. , Hoang Phu , Gandevia Simon C. , Bilston Lynne E.
Published: June 2012

The plantarflexors of the lower limb are often assumed to act as independent actuators, but the validity of this assumption is the subject of considerable debate. This study aims to determine the degree to which passive changes in gastrocnemius muscle length, induced by knee motion, affect the tension in the adjacent soleus muscle. A second aim is to quantify the magnitude of myofascial passive force transmission between gastrocnemius and adjacent soleus. Fifteen healthy volunteers participated. Simultaneous ultrasound images of the gastrocnemius and soleus muscles were obtained during passive knee flexion (0–90°), while keeping the ankle angle fixed at either 70° or 115°. Image correlation analysis was used to quantify muscle fascicle lengths in both muscles. The data show that the soleus muscle fascicles elongate significantly during gastrocnemius shortening. The approximate change in passive soleus force as a result of the observed change in fascicle length was estimated and appears to be <5 N, but this estimate is sensitive to the assumed slack length of soleus.
Dynamic compression promotes proliferation and neovascular networks of endothelial progenitor cells in demineralized bone matrix scaffold seed
Authors: Kong Zhan , Li Jianjun , Zhao Qun , Zhou Zhendong , Yuan Xiangnan , Yang Dongxiang , Chen Xu
Published: June 2012

Neovascularization is required for bone formation and successful fracture healing. In the process of neovascularization, endothelial progenitor cells (EPCs) play an important role and finish vascular repair through reendothelialization to promote successful fracture healing. In this study, we found that dynamic compression can promote the proliferation and capillary-like tube formation of EPCs in the demineralized bone matrix (DBM) scaffold seed. EPCs isolated from the bone marrow of rats have been cultured in DBM scaffolds before dynamic compression and then seeded in the DBM scaffolds under dynamic conditions. The cells/scaffold constructs were subjected to cyclic compression with 5% strain and at 1 Hz for 4 h/day for 7 consecutive days. By using MTT and real-time PCR, we found that dynamic compression can significantly induce the proliferation of EPCs in three-dimensional culture with an even distribution of cells onto DBM scaffolds. Both in vitro and in vivo, the tube formation assays in the scaffolds showed that the loaded EPCs formed significant tube-like structures. These findings suggest that dynamic compression promoted the vasculogenic activities of EPCs seeded in the scaffolds, which would benefit large bone defect tissue engineering.
Sympatho-adrenal activation by chronic intermittent hypoxia
Authors: Prabhakar Nanduri R. , Kumar Ganesh K. , Peng Ying-Jie
Published: June 2012

Recurrent apnea with chronic intermittent hypoxia (CIH) is a major clinical problem in adult humans and infants born preterm. Patients with recurrent apnea exhibit heightened sympathetic activity as well as elevated plasma catecholamine levels, and these phenotypes are effectively recapitulated in rodent models of CIH. This article summarizes findings from studies addressing sympathetic activation in recurrent apnea patients and rodent models of CIH and the underlying cellular and molecular mechanisms. Available evidence suggests that augmented chemoreflex and attenuated baroreflex contribute to sympathetic activation by CIH. Studies on rodents showed that CIH augments the carotid body response to hypoxia and attenuates the carotid baroreceptor response to increased sinus pressures. Processing of afferent information from chemoreceptors at the central nervous system is also facilitated by CIH. Adult and neonatal rats exposed to CIH exhibit augmented catecholamine secretion from the adrenal medulla. Adrenal demedullation prevents the elevation of circulating catecholamines in CIH-exposed rodents. Reactive oxygen species (ROS)-mediated signaling is emerging as the major cellular mechanism triggering sympatho-adrenal activation by CIH. Molecular mechanisms underlying increased ROS generation by CIH seem to involve transcriptional dysregulation of genes encoding pro-and antioxidant enzymes by hypoxia-inducible factor-1 and -2, respectively.
Iron and vitamin status biomarkers and its association with physical fitness in adolescents: the HELENA study
Authors: Gracia-Marco Luis , Valtueña Jara , Ortega Francisco B. , Pérez-López Faustino R. , Vicente-Rodríguez Germán , Breidenassel Christina , Ferrari Marika , Molnar Dénes , Widhalm Kurt , de Henauw Stefaan , Kafatos Anthony , Diaz Ligia E. , Gottrand Frédéric , Maiani Giuseppe , Stehle Peter , Castillo Manuel J. , Moreno Luis A. , González-Gross Marcela ,   on behalf of the HELENA Study Group
Published: June 2012

There is a lack of studies that analyze the association between micronutrient-related biomarker status and physical fitness in adolescents. In the present study, biochemical parameters for iron and vitamin status were studied, along with objective measures of physical fitness in healthy male and female European adolescents. One thousand eighty-nine adolescents (580 girls, 12.5–17.5 yr) from the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) cross-sectional study were included. Hierarchical linear models were performed to determine the associations between micronutrient biomarkers and physical fitness. Age, seasonality, latitude, body mass index, menarche (in girls), and physical activity were used as covariates. For cardiorespiratory fitness, concentrations of hemoglobin, retinol, and vitamin C in male adolescents and β-carotene and 25(OH)D in female adolescents were associated with maximal oxygen consumption. For muscular fitness, concentrations of hemoglobin, β-carotene, retinol, and α-tocopherol in male adolescents and β-carotene and 25(OH)D in female adolescents were associated with better performance of the standing long jump test. In summary, concentrations of hemoglobin and most antioxidant vitamins in male adolescents and β-carotene and 25(OH)D in female adolescents were positively associated with cardiorespiratory and muscular fitness, after controlling for relevant confounders. The associations between physical fitness and iron or vitamin status observed in this cross-sectional study in adolescents should be followed up by a study specifically designed to evaluate causal relationships.
Development of motor maps in rats and their modulation by experience
Authors: Young Nicole A. , Vuong Jennifer , Teskey G. Campbell
Published: June 2012

While a substantial literature demonstrates the effect of differential experience on development of mammalian sensory cortices and plasticity of adult motor cortex, characterization of differential experience on the functional development of motor cortex is meager. We first determined when forelimb movement representations (motor maps) could be detected in rats during postnatal development and then whether their motor map expression could be altered with rearing in an enriched environment consisting of group housing and novel toys or skilled learning by training on the single pellet reaching task. All offspring had high-resolution intracortical microstimulation (ICMS)-derived motor maps using methodologies previously optimized for the adult rat. First, cortical GABA-mediated inhibition was depressed by bicuculline infusion directly into layer V of motor cortex and ICMS-responsive points were first reliably detected on postnatal day (PND) 13. Without relying on bicuculline disinhibition of cortex, motor maps emerged on PND 35 and then increased in size until PND 60 and had progressively lower movement thresholds. Second, environmental enrichment did not affect initial detection of responsive points and motor maps in non-bicuculline-treated pups on PND 35. However, motor maps were larger on PND 45 in enriched rat pups relative to pups in the standard housing condition. Rats in both conditions had similar map sizes on PNDs 60, 75, and 90. Third, reach training in rat pups resulted in an internal reorganization of the map in the hemisphere contralateral, but not ipsilateral, to the trained forelimb. The map reorganization was expressed as proportionately more distal (digit and wrist) representations on PND 45. Our data indicate that both environmental enrichment and skilled reach training experience can differentially modify expression of motor maps during development.
Extracting synergies in gait: using EMG variability to evaluate control strategies
Authors: Ranganathan Rajiv , Krishnan Chandramouli
Published: June 2012

There has been extensive debate as to whether muscle synergies in motor tasks reflect underlying neural organization or simply correlations in muscle activity that are imposed by the task. One possible means of distinguishing these two alternatives is through the analysis of variability in the electromyogram (EMG). Here, we simulated EMG in eight lower-limb muscles and introduced hypothetical neural coupling between specific muscle groups. Neural coupling was simulated by introducing correlations in the neural activation commands to different muscles (positive, negative, or zero coupling). When the entire EMG signal was used for analysis, the extracted synergies reflected only simultaneous muscle activity, regardless of the neural coupling between the muscles. On the other hand, examining the variability in the EMG after subtracting the ensemble average was successful in identifying the simulated neural coupling. The extracted synergies from these two methods were also different when we analyzed data from participants during treadmill walking. The results emphasize the importance of examining EMG variability to understand the neural basis of muscle synergies.
On the origin of sustained negative BOLD response
Authors: Moraschi Marta , DiNuzzo Mauro , Giove Federico
Published: June 2012

Several brain regions exhibit a sustained negative BOLD response (NBR) during specific tasks, as assessed with functional magnetic resonance imaging. The origin of the NBR and the relationships between the vascular/metabolic dynamics and the underlying neural activity are highly debated. Converging evidence indicates that NBR, in human and non-human primates, can be interpreted in terms of decrease in neuronal activity under its basal level, rather than a purely vascular phenomenon. However, the scarcity of direct experimental evidence suggests caution and encourages the ongoing utilization of multimodal approaches in the investigation of this effect.
Inhibition of Bone Loss byCissus quadrangularisin Mice: A Preliminary Report
Authors: Banu Jameela , Varela Erika , Bahadur Ali N. , Soomro Raheela , Kazi Nishu , Fernandes Gabriel
Published: June 2012

Women drastically loose bone during and after menopause leading to osteoporosis, a disease characterized by low bone mass increasing the risk of fractures with minor trauma. Existing therapies mainly reduce bone resorption, however, all existing drugs have severe side effects. Recently, the focus is to identify alternative medicines that can prevent and treat osteoporosis with minimal or no side effects. We usedCissus quadrangularis(CQ), a medicinal herb, to determine its effects on bone loss after ovariectomy in C57BL/6 mice. Two-month old mice were either sham operated or ovariectomized and fed CQ diet. After eleven weeks, mice were sacrificed and the long bones scanned using pQCT andμCT. In the distal femoral metaphysis, femoral diaphysis, and proximal tibia, control mice had decreased cancellous and cortical bone, while CQ-fed mice showed no significant differences in the trabecular number, thickness, and connectivity density, between Sham and OVX mice, except for cortical bone mineral content in the proximal tibia. There were no changes in the bone at the tibio-fibular junction between groups. We conclude that CQ effectively inhibited bone loss in the cancellous and cortical bones of femur and proximal tibia in these mice.
Involvement of Heme Oxygenase-1 Participates in Anti-Inflammatory and Analgesic Effects of Aqueous Extract ofHibiscus taiwanensis
Authors: Liu Shu-Ling , Deng Jeng-Shyan , Chiu Chuan-Sung , Hou Wen-Chi , Huang Shyh-Shyun , Lin Wang-Ching , Liao Jung-Chun , Huang Guan-Jhong
Published: June 2012

Anti-inflammatory effects of the aqueous extract ofHibiscus taiwanensis(AHT) were used in lipopolysaccharide (LPS-)stimulated mouse macrophage RAW264.7 cells and carrageenan (Carr-)induced mouse paw edema model. When RAW264.7 macrophages were treated with AHT together with LPS, a concentration-dependent inhibition of nitric oxide (NO), tumor necrosis factor (TNF-α), and prostaglandin E2 (PGE2) levels productions were detected. Western blotting revealed that AHT blocked protein expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), and elevated heme oxygenase-1 (HO-1), significantly. In the animal test, AHT decreased the paw edema at the 4th and the 5th h after Carr administration, and it increased the activities of catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) in the paw tissue. We also demonstrated AHT decreased the NO, TNF-α, and PGE2 levels on the serum level at the 5th h after the Carr injection. Western blotting revealed that AHT decreased Carr-induced iNOS, and COX-2, and increased HO-1 expressions at the 5th h in the edema paw. These findings demonstrated that AHT has excellent anti-inflammatory activitiesin vitroandin vivoand thus it has great potential to be used as a source for natural health products.
Study of Anterior Chamber Aqueous Tube Shunt by Fourier-Domain Optical Coherence Tomography
Authors: Jiang Chunhui , Li Yan , Huang David , Francis Brian A.
Published: June 2012

Purpose. This cross-sectional, observational study used Fourier-domain optical coherence tomography (OCT) to examine the position, patency, and the interior entrance site of anterior chamber (AC) aqueous tube shunts.Methods. The OCT, slitlamp biomicroscopy, and gonioscopy findings of 23 eyes of 18 patients with AC shunts were collected and compared.Results. OCT images demonstrated the shunt position and patency in all 23 eyes, and the details of the AC entrance in 16 eyes. The position of the tube varied, with the majority (14/23) on the surface of the iris. The exact position of the AC entrance relative to Schwalbe’s line (SL) could be determined in 9 eyes (posterior to SL in 7 eyes, anterior in 2 eyes). At the AC entrance, growth of fibrous scar tissue was present between the tube and the corneal endothelium in all 16 eyes in which the entrance could be clearly visualized. It’s a new finding that could not be visualized by slitlamp examination or lower resolution OCT.Conclusion. Compared to slitlamp examination, Fourier-domain OCT of AC tube shunts provided more detailed anatomic information regarding the insertion level relative to SL, scar tissue between the tube and the corneal endothelium, and patency of the tube opening.
Cross-Modal Recruitment of Primary Visual Cortex by Auditory Stimuli in the Nonhuman Primate Brain: A Molecular Mapping Study
Authors: Hirst Priscilla , Javadi Khomami Pasha , Gharat Amol , Zangenehpour Shahin
Published: June 2012

Recent studies suggest that exposure to only one component of audiovisual events can lead to cross-modal cortical activation. However, it is not certain whether such crossmodal recruitment can occur in the absence of explicit conditioning, semantic factors, or long-term associations. A recent study demonstrated that crossmodal cortical recruitment can occur even after a brief exposure to bimodal stimuli without semantic association. In addition, the authors showed that the primary visual cortex is under such crossmodal influence. In the present study, we used molecular activity mapping of the immediate early gene zif268. We found that animals, which had previously been exposed to a combination of auditory and visual stimuli, showed increased number of active neurons in the primary visual cortex when presented with sounds alone. As previously implied, this crossmodal activation appears to be the result of implicit associations of the two stimuli, likely driven by their spatiotemporal characteristics; it was observed after a relatively short period of exposure (~45 min) and lasted for a relatively long period after the initial exposure (~1 day). These results suggest that the previously reported findings may be directly rooted in the increased activity of the neurons occupying the primary visual cortex.
Proton Transfer Equilibria and Critical Behavior of H-Bonding
Authors: Sobczyk L. , Czarnik-Matusewicz B. , Rospenk M. , Obrzud M.
Published: June 2012

The aim of the present paper is an analysis of the hydrogen bond properties for the acid-base systems depending on the ability to the proton transfer in the formulation of the Brönsted approach. After definition of the proton transfer equilibrium expressed by using the equation log KPT=ξΔpKN, various examples of different physical properties, such as dipole moments, IR spectra, and nuclear magnetic resonances, are presented which correlate with the ΔpKN value. In such a way, a critical state of hydrogen bonding can be defined that corresponds to the potential of the proton motion for either single minimum or double minimum with low barrier. A particular attention in this paper found electronic spectra which have not been analysed so far and the quantitative analysis of the vibrational polarizability which can reach very high values of the order of electronic polarizability.
Three-Dimensional Acoustic Source Mapping with Different Beamforming Steering Vector Formulations
Authors: Sarradj Ennes
Published: June 2012

Acoustic source mapping techniques using acoustic sensor arrays and delay-and-sum beamforming techniques suffer from bad spatial resolution at low-aperture-based Helmholtz numbers. This is especially a problem for three-dimensional map grids, when the sensor array is not arranged around the region spanned by the grid but on only one side of it. Then, the spatial resolution of the result map in the direction pointing away from the array is much worse than in the other lateral directions. Consequently, deconvolution techniques need to be applied. Some of the most efficient deconvolution techniques rely on the properties of the spatial beamformer filters used. As these properties
are governed by the steering vectors, four different steering vector formulations from the literature are examined, and their theoretical background is discussed. It is found that none of the formulations provide both the correct location and source strength. As a practical example the CLEAN-SC deconvolution methodology is applied to simulated data for a three-source scenario. It is shown that the different steering vector formulations are not equally well suited for three-dimensional application. The two preferred formulations enable the correct estimation of the source location at the cost of a negligible error in the estimated source strength.
Survival Benefit of Adjuvant Radiation Therapy for Gastric Cancer following Gastrectomy and Extended Lymphadenectomy
Authors: Snyder R. A. , Castaldo E. T. , Bailey C. E. , Phillips S. E. , Chakravarthy A. B. , Merchant N. B.
Published: June 2012

Purpose. Although randomized trials suggest a survival benefit of adjuvant chemotherapy and radiation therapy (XRT) for gastric adenocarcinoma, its use in patients who undergo an extended lymphadenectomy is less clear. The purpose of this study was to determine if a survival benefit exists in gastric cancer patients who receive adjuvant XRT following resection with extended lymphadenectomy.Methods. The SEER registry was queried for records of patients with resected gastric adenocarcinoma from 1988 to 2007. Multivariable Cox regression models were used to assess independent prognostic factors affecting overall survival (OS) and disease-specific survival (DSS).Results. Of 15,060 patients identified, 3,208 (21%) received adjuvant XRT. Adjuvant XRT was independently associated with improved OS (HR 0.67, CI 0.64–0.71) and DSS (HR 0.69, CI 0.65–0.73) in stages IB through IV (M0). This OS and DSS benefit persisted regardless of the extent of lymphadenectomy. Furthermore, lymphadenectomy with >25 LN resected was associated with improved OS and DSS compared with <15 LN or 15–25 LN.Conclusion. This population-based study shows a survival benefit of adjuvant XRT following gastrectomy that persists in patients who have an extended lymphadenectomy. Furthermore, removal of >25 LNs results in improved OS and DSS compared with patients who have fewer LNs resected.
Pulmonary Immune-Compartment-Specific Interferon Gamma Responses in HIV-Infected Individuals with Active Tuberculosis (TB) in an Area of High TB Prevalence
Authors: Buldeo S. , Murdoch D. M. , Suchard M. S.
Published: June 2012

There is a paucity of data on the pulmonary immune-compartment interferon gamma (IFNγ) response toM. tuberculosis, particularly in settings of high tuberculosis (TB) prevalence and in HIV-coinfected individuals. This data is necessary to understand the diagnostic potential of commercially available interferon gamma release assays (IGRAs) in both the pulmonary immune-compartment and peripheral blood. We used intracellular cytokine staining by flow cytometry to assess the IFNγ response to purified protein derivative (PPD) and early secretory antigen 6 (ESAT6) in induced sputa (ISp) and blood samples from HIV-infected, smear-negative, TB suspects. We found that individuals with active TB disease produced significantly less IFNγ in response to PPD in their induced sputa samples than individuals with non-active TB (control group). This difference was not reflected in the peripheral blood, even within the CD27− CD4+ memory T lymphocyte population. These findings suggest that progression to active TB disease may be associated with the loss of IFNγ secretion at the site of primary infection. Our findings highlight the importance of studying pulmonary immune-compartmentM. tuberculosisspecific responses to elucidate IFNγ secretion across the spectrum of TB disease.