bluuebunny/crossref_metadata_2025 huggingface dataset:
Study of the Solid-Matrix Phosphorescence Properties of a Heterocyclic Aromatic Amine and the Heat Capacities of Glucose Glasses as the Temperature Decreases
Authors: Hubbard Sara E. , Hurtubise Robert J.
Published: June 2008

The heat capacities were obtained from 294 to 133 K for four glucose-glass systems. Two of the glasses were prepared from crystalline glucose. One of the glasses contained the heavy-atom salt NaI and the other glass did not contain NaI. The other two glasses were similar, but they were prepared from glucose melts. Correlations were developed between the solid-matrix phosphorescence (SMP) lifetimes and intensities of 2-amino-1-methyl-6-phenylimidazo[4,5- b]pyridine (PhIP) in the glucose glasses and the heat capacities of the glucose sugar glasses as the temperature was lowered. Several plots of reciprocal SMP lifetime versus reciprocal temperature and reciprocal SMP lifetime versus reciprocal heat capacity were compared. Also, the reciprocal SMP intensity versus reciprocal temperature plots were compared with the corresponding reciprocal SMP intensity versus reciprocal heat capacity plots. In addition, basic photophysical equations were used to develop relationships among the lifetime data, the intensity data, and the heat capacity data. The heat capacity data and SMP lifetime data, obtained as the temperature was lowered, were discussed in relationship to low-frequency vibrational modes and β-relaxation phenomena in the glucose glasses. The discussion of these phenomena offered explanations for some of the loss of the excited triplet-state energy of PhIP in the glucose sugar glasses.
Fluorescence Resonance Energy Transfer Based MCM-EDTA-Tb3+-MES Sensor
Authors: Smith Clint B. , Erson John E. , Massaro Richard D. , Tatineni Balaji , Kam Kinson C. , Tepper Gary C.
Published: June 2008

An in situ mesopourous surface imprinted polymeric (SIP) sensor was synthesized for a highly sensitive, selective, and kinetically faster detection of the high-vapor-pressure nerve gas surrogate methyl salicylate (MES). Visual detection occurred on the filtrate thin films at 25 pM. Other nerve gas surrogates, TP, DMP, DMMP, PMP, and 1,4-thioxane, were tested and showed a decrease in sensitivity compared to MES. In addition, 2,6-dipicolinic acid (DPA), a biological indicator, was also investigated and showed a decrease in sensitivity compared to MES. Finally, the detection plateau was reached at 40 s and at 1.5 × 10−4 M from pH 6–11.
Method for the Estimation of the Mean Lorentzian Bandwidth in Spectra Composed of an Unknown Number of Highly Overlapped Bands
Authors: Lórenz-Fonfría Víctor A. , Padrós Esteve
Published: June 2008

We introduce a method for the estimation of the mean Lorentzian bandwidth of the component bands in a spectrum. The method is computationally simple, using only the module of the Fourier transform of the spectrum, and its first derivative. Moreover, the presented method does not require knowledge of the number of bands in the spectrum, their band positions, or their band areas. Furthermore, it works on spectra containing Lorentzian bands, as well as Gaussian and Voigtian bands. Therefore, the introduced method seems especially well suited for obtaining a representative Lorentzian width for highly overlapped bands, independent of their number and Lorentzian/Gaussian character. We describe how different experimental limitations (spectral truncation, offset error, presence of noise, etc.) may affect the performance of the method, and when required we propose effective alternatives to minimize their effects. Finally, we show the application of the method to an experimental spectrum: the amide I band of a dry film of the solubilized ADP/ATP carrier. The estimation of the mean Lorentzian width can allow, for instance, for a more objective selection of the deconvolution width in Fourier self-deconvolution, allowing for a more objective and reliable analysis of the amide I band of proteins. The mean Lorentzian width can also be useful to obtain an estimation of the homogenous broadening and vibrational relaxation of the amide I vibration of proteins, without requiring complex pump-probe experiments.
A Strategy to Prevent Signal Losses, Analyte Decomposition, and Fluctuating Carbon Contamination Bands in Surface-Enhanced Raman Spectroscopy
Authors: Yeo Boon-Siang , Schmid Thomas , Zhang Weihua , Zenobi Renato
Published: June 2008

Signal losses and fluctuating carbon contamination bands are “bottlenecks” in the application of surface-enhanced Raman spectroscopy (SERS) for reliable chemical analysis. They originate mainly from prolonged laser irradiation of the sample during data collection, which causes analyte decomposition and/or loss of the enhancing capabilities of the adsorption site. In this work, a laser illumination/signal collection technique, the “multiple points collection” (MPC) method is introduced to circumvent these problems. The MPC method is based on the use of a pair of galvanic mirrors to scan the laser beam rapidly and steadily across the sample surface. Each position is irradiated for <10 μs, at a rate of ∼0.5 Hz. The SER spectrum is obtained by summing the signals collected from a large array of non-overlapping sample points. The MPC is compared with the conventional “single point collection” method, in which the laser beam is statically focused onto a particular spot and the scattered signals acquired. The MPC has the following advantages: (1) illumination and collection efficiencies are not compromised, (2) signal losses originating from analyte decomposition and/or alteration of the enhancing capabilities of the adsorption site are avoided, (3) high-quality SER spectra for analytes such as biomolecules and dipicolinic acid (a common marker for bacteria spores) can be easily obtained, and (4) the occurrence of broad amorphous carbon bands and the commonly observed temporal fluctuations in SERS are prevented. The success of the MPC is attributed to the reduction of local sample heating, as the time interval between the laser irradiations of a spot is much longer than the actual irradiation time itself.
Assessment of Near-Infrared Path Length in Fibrous Phantom and Muscle Tissue
Authors: Gussakovsky Eugene , Kupriyanov Valery
Published: June 2008

The first derivative of the pseudo-absorption spectrum of a water-loaded cotton wool (water–CW) phantom, which mimics muscle tissues, was used to determine the light path length in the near-infrared (NIR) region. The light path length increased as the density of the turbid medium decreased. It is independent of both water content in the range of 75–85% (by weight) and the diffuse reflecting reference used to determine the pseudoabsorbance. The path length determination procedure was verified by measurements of diffuse reflectance in chicken breast tissue for which the path length of 1.8 mm (differential path length factor, DPF = 2.1) was found to be similar to the path length of NIR light of 1.5–2.2 mm (DPF = 1.8–2.6) in a water–CW phantom of density similar to chicken breast. We conclude that the NIR light path length can serve as a characteristic of muscle tissue density.
Increased Plasma Apolipoprotein C-III Concentration Independently Predicts Cardiovascular Mortality: The Hoorn Study
Authors: Scheffer Peter G , Teerlink Tom , Dekker Jacqueline M , Bos Griët , Nijpels Giel , Diamant Michaela , Kostense Piet J , Stehouwer Coen D A , Heine Robert J
Published: June 2008

Background: Hypertriglyceridemia is a cardiovascular risk factor. Apolipoprotein C-III (apoC-III) is an important determinant of the catabolic rate of triglyceride-rich lipoproteins. The aim of this study was to investigate the prognostic value of plasma apoC-III concentrations for cardiovascular mortality.

Methods: We performed this prospective study in 2244 subjects (ages 49–77 years) who participated in the Hoorn Study. During a mean follow-up of 15 years, 504 individuals died: 231 of cardiovascular disease, 180 of cancer, and 93 of other causes. Cardiovascular disease risk factors and plasma apoC-III concentrations were measured at baseline.

Results: The age- and sex-adjusted plasma apoC-III concentration was prospectively associated with cardiovascular mortality (P < 0.001). After adjustment for traditional risk factors, including fasting triglycerides, the hazard ratio (95% CI) for cardiovascular death between the highest and the lowest quartile of apoC-III was 1.85 (1.02–3.38). High concentrations of apoC-III did not appear to be associated with noncardiovascular mortality.

Conclusions: In this general population cohort, a high apoC-III concentration in plasma, independently of fasting triglycerides and other traditional risk factors, predicts cardiovascular mortality.
Diagnostic Accuracy of Serum Ceruloplasmin in Wilson Disease: Determination of Sensitivity and Specificity by ROC Curve Analysis among ATP7B-Genotyped Subjects
Authors: Mak Chloe M , Lam Ching-Wan , Tam Sidney
Published: June 2008

Background: A serum ceruloplasmin concentration below 0.20 g/L is conventionally considered as one of the major diagnostic criteria for Wilson disease. This decision threshold has not been fully validated for its diagnostic characteristics, however. In this study, we evaluated various decision thresholds of serum ceruloplasmin concentration in the diagnosis of Wilson disease based on genotype-verified Wilson disease patients, carriers, and normal individuals.

Methods: Serum ceruloplasmin concentration was measured by a nephelometric method in 57 Wilson disease patients and 71 family members (49 heterozygotes and 22 wild-type homozygotes), a validation group of 25 subjects clinically suspected of Wilson disease, and 690 normal individuals. We performed ROC analysis using Analyze-it software and confirmed the genotypes by direct DNA sequencing of ATP7B.

Results: Serum ceruloplasmin concentrations <0.20, 0.14, and 0.10 g/L showed positive predictive values of 48.3%, 100%, and 100%, respectively, and negative predictive values of 98.7%, 97.1%, and 91.9%. In the validation group, a serum ceruloplasmin threshold of 0.14 g/L rendered 100% sensitivity and specificity. Forty of 690 healthy subjects had serum ceruloplasmin concentrations <0.20 g/L; however, these 40 individuals had normal genotypes by DNA sequencing, and none of the 40 had ceruloplasmin concentrations <0.14 g/L.

Conclusions: The diagnostic accuracy for Wilson disease using a serum ceruloplasmin concentration of 0.14 g/L as the local decision threshold was better than that using a threshold of 0.20 g/L. We suggest that laboratories providing ceruloplasmin assays determine decision thresholds based on local populations.
Low Vitamin D Status in a Representative Sample of Youth From Québec, Canada
Authors: Mark Sean , Gray-Donald Katherine , Delvin Edgard E , O'Loughlin Jennifer , Paradis Gilles , Levy Emile , Lambert Marie
Published: June 2008

Background: Adequate vitamin D status is important for bone growth and mineralization and has been implicated in the regulation of autoimmunity, metabolic function, and cancer prevention. There are no reports of population-based studies on the vitamin D status of Canadian youth, a population with mandatory fortification of foods.

Methods: We measured plasma 25-hydroxyvitamin D [25(OH)D], the best indicator of vitamin D status, in a school-based cross-sectional sample of representative French Canadian youth (n = 1753) ages 9, 13, and 16 years living in Québec (latitude: 45°–48°N). Blood samples were collected from January to May 1999. We defined 25(OH)D deficiency as ≤27.5 nmol/L, hypovitaminosis as ≤37.5 nmol/L, and optimal as >75.0 nmol/L.

Results: More than 93% of youth in each age and sex group had suboptimal 25(OH)D concentrations. The prevalence of 25(OH)D deficiency increased with age in both sexes (P < 0.0001). It was 2%, 3%, and 13% in 9-, 13-, and 16-year-old boys and 2%, 8%, and 10% in 9-, 13-, and 16-year-old girls. Girls with higher body mass index and girls from households with lower income had lower 25(OH)D concentrations. These effects were not observed in boys.

Conclusions: Inadequate vitamin D status is a potentially serious public health problem among children and adolescents in Québec. Youth living at high latitudes in countries with and without mandatory fortification of vitamin D are likely at heightened risk of 25(OH)D deficiency. These results call for renewed efforts to ensure adequate vitamin D intake among growing children and adolescents.
Prevalence and Determinants of Workplace Violence of Health Care Workers in a Psychiatric Hospital in Taiwan
Authors: Chen Wen‐Ching , Hwu Hai‐Gwo , Kung Shou‐Mei , Chiu Hsien‐Jane , Wang Jung‐Der
Published: June 2008

Prevalence and Determinants of Workplace Violence of Health Care Workers in a Psychiatric Hospital in Taiwan: Wen‐Ching Chen, et al. Yu‐Li Hospital, Department of Health, Executive Yuan, Taiwan—Workplace violence, a possible cause of job stress, has recently become an important concern in occupational health. This study determined the prevalence of workplace violence and its risk factors for employees at a psychiatric hospital in Taiwan. A questionnaire developed by ILO/ICN/WHO/PSI was first translated and validated. It was then used to survey the prevalence of workplace violence in the last 12 months experienced by all nursing aides, nurses, and clerks at the hospital. Multiple logistic regression models were constructed to discover the determinants of violence. A total of 222 out of 231 surveyed workers completed a valid questionnaire. The one‐year prevalence rates of physical violence (PV), verbal abuse, bullying/mobbing, sexual harassment, and racial harassment were 35.1, 50.9, 15.8, 9.5, and 4.5%, respectively. The prevalence of PV at this hospital was higher than that reported by other countries for the health sector. A high anxiety level was associated with the occurrence of PV. These results need to be corroborated by future investigation. A training program may be required for high risk groups to reduce workplace violence.
A European Framework to Address Psychosocial Hazards
Authors: Leka Stavroula , Kortum Evelyn
Published: June 2008

A European Framework to Address Psychosocial Hazards: Stavroula Leka, et al. Institute of Work, Health and Organisations, University of Nottingham, UK—Over the past decades, emphasis has been placed on the changing nature of work and new forms of risk that could negatively affect employee health and safety. These are mainly associated with new types of occupational hazards that have been termed psychosocial. Issues such as work‐related stress, bullying and harassment are now receiving attention on a global basis and efforts have been made to address them at the workplace level. However, it has been acknowledged that despite developments of policy in this area, there still appear to be a broad science‐policy gap and an even broader one between policy and practice. The WHO Network of Collaborating Centers in Occupational Health has, since the late 1990s, been supporting a dedicated program of work on psychosocial factors and work‐related stress. Part of the Network's work is currently focusing on the translation of existing knowledge into practice in the area of psychosocial risk management. This program has identified that the optimum way forward lies in the development of a European framework for psychosocial risk management. This framework will serve as the basis for coordination of research activities and preventive action with an emphasis on evidence based interventions and best practice on an international basis.
The Myelopoietic Supportive Capacity of Mesenchymal Stromal Cells Is Uncoupled from Multipotency and Is Influenced by Lineage Determination and Interference with Glycosylation
Authors: Morad Vered , Pevsner-Fischer Meirav , Barnees Sivan , Samokovlisky Albena , Rousso-Noori Liat , Rosenfeld Rakefet , Zipori Dov
Published: June 2008

Cultured bone marrow stromal cells create an in vitro milieu supportive of long-term hemopoiesis and serve as a source for multipotent mesenchymal progenitor cells defined by their ability to differentiate into a variety of mesodermal derivatives. This study aims to examine whether the capacity to support myelopoiesis is coupled with the multipotency. Our results show that the myelopoietic supportive ability of stromal cells, whether from the bone marrow or from embryo origin, is not linked with multipotency; cell populations that possess multipotent capacity may or may not support myelopoiesis, whereas others, lacking multipotency, may possess full myelopoietic supportive ability. However, upon differentiation, the ability of multipotent mesenchymal progenitors to support myelopoiesis is varied. Osteogenic differentiation did not affect myelopoietic supportive capacity, whereas adipogenesis resulted in reduced ability to support the maintenance of myeloid progenitor cells. These differences were accompanied by a divergence in glycosylation patterns, as measured by binding to lectin microarrays; osteogenic differentiation was associated with an increased level of antennarity of N-linked glycans, whereas adipogenic differentiation caused a decrease in antennarity. Inhibition of glycosylation prior to seeding the stroma with bone marrow cells resulted in reduced capacity of the stromal cells to support the formation of cobblestone areas. Our data show that myelopoietic support is unrelated to the multipotent phenotype of cultured mesenchymal progenitors but is dependent on the choice of differentiation pathway and upon correct glycosylation of the stromal cells.

Disclosure of potential conflicts of interest is found at the end of this article.
Direct-Current Electrical Field Guides Neuronal Stem/Progenitor Cell Migration
Authors: Li Lei , El-Hayek Youssef H. , Liu Baosong , Chen Yonghong , Gomez Everlyne , Wu Xiaohua , Ning Ke , Li Lijun , Chang Ning , Zhang Liang , Wang Zhengguo , Hu Xiang , Wan Qi
Published: June 2008

Direct-current electrical fields (EFs) promote nerve growth and axon regeneration. We report here that at physiological strengths, EFs guide the migration of neuronal stem/progenitor cells (NSPCs) toward the cathode. EF-directed NSPC migration requires activation of N-methyl-d-aspartate receptors (NMDARs), which leads to an increased physical association of Rho GTPase Rac1-associated signals to the membrane NMDARs and the intracellular actin cytoskeleton. Thus, this study identifies the EF as a directional guidance cue in controlling NSPC migration and reveals a role of the NMDAR/Rac1/actin signal transduction pathway in mediating EF-induced NSPC migration. These results suggest that as a safe physical approach in clinical application, EFs may be developed as a practical therapeutic strategy for brain repair by directing NSPC migration to the injured brain regions to replace cell loss.

Disclosure of potential conflicts of interest is found at the end of this article.
EWS-FLI1 Causes Neuroepithelial Defects and Abrogates Emigration of Neural Crest Stem Cells
Authors: Coles Edward G. , Lawlor Elizabeth R. , Bronner-Fraser Marianne
Published: June 2008

The most frequently occurring chromosomal translocation that gives rise to the Ewing's sarcoma family of tumors (ESFT) is the chimeric fusion gene EWS-FLI1 that encodes an oncogenic protein composed of the N terminus of EWS and the C terminus of FLI1. Although the genetic basis of ESFT is fairly well understood, its putative cellular origin remains to be determined. Previous work has proposed that neural crest progenitor cells may be the causative cell type responsible for ESFT. However, surprisingly little is known about the expression pattern or role of either wild-type EWS or wild-type FLI1 in this cell population during early embryonic development. Using the developing chick embryo as a model system, we identified EWS expression in emigrating and migratory neural crest stem cells, whereas FLI1 transcripts were found to be absent in these populations and were restricted to developing endothelial cells. By ectopically expressing EWS-FLI1 or wild-type FLI1 in the developing embryo, we have been able to study the cellular transformations that ensue in the context of an in vivo model system. Our results reveal that misexpression of the chimeric EWS-FLI1 fusion gene, or wild-type FLI1, in the developing neural crest stem cell population leads to significant aberrations in neural crest development. An intriguing possibility is that misexpression of the EWS-FLI1 oncogene in neural crest-derived stem cells may be an initiating event in ESFT genesis.

Disclosure of potential conflicts of interest is found at the end of this article.
Scalable Selection of Hepatocyte- and Hepatocyte Precursor-Like Cells from Culture of Differentiating Transgenically Modified Murine Embryonic Stem Cells
Authors: Drobinskaya Irina , Linn Thomas , Šarić Tomo , Bretzel Reinhard G. , Bohlen Heribert , Hescheler Jürgen , Kolossov Eugen
Published: June 2008

Potential therapeutic applications of embryonic stem cell (ESC)-derived hepatocytes are limited by their relatively low output in differentiating ESC cultures, as well as by the danger of contamination with tumorigenic undifferentiated ESCs. To address these problems, we developed transgenic murine ESC clones possessing bicistronic expression vector that contains the α-fetoprotein gene promoter driving a cassette for the enhanced green “live” fluorescent reporter protein (eGFP) and a puromycin resistance gene. Under established culture conditions these clones allowed for both monitoring of differentiation and for puromycin selection of hepatocyte-committed cells in a suspension mass culture of transgenic ESC aggregates (“embryoid bodies” [EBs]). When plated on fibronectin, the selected eGFP-positive cells formed colonies, in which intensely proliferating hepatocyte precursor-like cells gave rise to morphologically differentiated cells expressing α-1-antitrypsin, α-fetoprotein, and albumin. A number of cells synthesized glycogen and in some of the cells cytokeratin 18 microfilaments were detected. Major hepatocyte marker genes were expressed in the culture, along with the gene and protein expression of stem/progenitor markers, suggesting the features of both hepatocyte precursors and more advanced differentiated cells. When cultured in suspension, the EB-derived puromycin-selected cells formed spheroids capable of outgrowing on an adhesive substrate, resembling the behavior of fetal mouse hepatic progenitor cells. The established system based on the highly efficient selection/purification procedure could be suitable for scalable generation of ESC-derived hepatocyte- and hepatocyte precursor-like cells and offers a potential in vitro source of cells for transplantation therapy of liver diseases, tissue engineering, and drug and toxicology screening.

Disclosure of potential conflicts of interest is found at the end of this article.
Diurnal profiling of neuroendocrine genes in murine heart, and shift in proopiomelanocortin gene expression with pressure-overload cardiac hypertrophy
Authors: Chalmers Jennifer A , Lin Shuo-Yen J , Martino Tami A , Arab Sara , Liu Peter , Husain Mansoor , Sole Michael J , Belsham Denise D
Published: June 2008

Neuroendocrine peptides express biologic activity relevant to the cardiovascular system, including regulating heart rate and blood pressure, though little is known about the mechanisms involved. Here, we investigated neuroendocrine gene expression underlying diurnal physiology of the heart. We first used microarray and RT-PCR analysis and demonstrate the simultaneous expression of neuroendocrine genes in normal murine heart, including POMC, GnRH, neuropeptide Y, leptin receptor, GH-releasing hormone, cocaine- and amphetamine-regulated transcript, proglucagon, and galanin. We examined diurnal gene expression profiles, with cosinar bioinformatics to evaluate statistically significant rhythms. The POMC gene exhibits a day/night, circadian or diurnal, pattern of expression in heart, and we postulated that this may be important to cardiac growth and renewal. POMC diurnal gene rhythmicity is altered in pressure-overload cardiac hypertrophy, when compared with control heart, and levels increased at the dark-to-light transition times. These findings are also consistent with the proposal that neuropeptides mediate adverse remodeling processes, such as occur in pathologic hypertrophy. To investigate cellular responses, we screened three cell lines representing fibroblasts, cardiac myocytes, and vascular smooth muscle cells (NIH3T3, heart line 1, and mouse vascular smooth muscle cell line 1 (Movas-1) respectively). POMC mRNA expression is the most notable in Movas-1 cells and, furthermore, exhibits rhythmicity with culture synchronization. Taken together, these results highlight the diverse neuroendocrine mRNA expression profiles in cardiovasculature, and provide a novel model vascular culture system to research the role these neuropeptides play in organ health, integrity, and disease.
Ginsenoside Rb1 stimulates glucose uptake through insulin-like signaling pathway in 3T3-L1 adipocytes
Authors: Shang Wenbin , Yang Ying , Zhou Libin , Jiang Boren , Jin Hua , Chen Mingdao
Published: June 2008

A series of clinical trials and animal experiments have demonstrated that ginseng and its major active constituent, ginsenosides, possess glucose-lowering action. In our previous study, ginsenoside Rb1 has been shown to regulate peroxisome proliferator-activated receptor γ activity to facilitate adipogenesis of 3T3-L1 cells. However, the effect of Rb1 on glucose transport in insulin-sensitive cells and its molecular mechanism need further elucidation. In this study, Rb1 significantly stimulated basal and insulin-mediated glucose uptake in a time- and dose-dependent manner in 3T3-L1 adipocytes and C2C12 myotubes; the maximal effect was achieved at a concentration of 1 μM and a time of 3 h. In adipocytes, Rb1 promoted GLUT1 and GLUT4 translocations to the cell surface, which was examined by analyzing their distribution in subcellular membrane fractions, and enhanced translocation of GLUT4 was confirmed using the transfection of GLUT4-green fluorescence protein in Chinese Hamster Ovary cells. Meanwhile, Rb1 increased the phosphorylation of insulin receptor substrate-1 and protein kinase B (PKB), and stimulated phosphatidylinositol 3-kinase (PI3K) activity in the absence of the activation of the insulin receptor. Rb1-induced glucose uptake as well as GLUT1 and GLUT4 translocations was inhibited by the PI3K inhibitor. These results suggest that ginsenoside Rb1 stimulates glucose transport in insulin-sensitive cells by promoting translocations of GLUT1 and GLUT4 by partially activating the insulin signaling pathway. These findings are useful in understanding the hypoglycemic and anti-diabetic properties of ginseng and ginsenosides.
Activation of ATP-sensitive potassium channels in rat pancreatic β-cells by linoleic acid through both intracellular metabolites and membrane receptor signalling pathway
Authors: Zhao Yu-Feng , Pei Jianming , Chen Chen
Published: June 2008

ATP-sensitive potassium channels (KATP channels) determine the excitability of pancreatic β-cells and importantly regulate glucose-stimulated insulin secretion (GSIS). Long-chain free fatty acids (FFAs) decrease GSIS after long-term exposure to β-cells, but the effects of exogenous FFAs on KATP channels are not yet well clarified. In this study, the effects of linoleic acid (LA) on membrane potential (MP) and KATP channels were observed in primary cultured rat pancreatic β-cells. LA (20 μM) induced hyperpolarization of MP and opening of KATP channels, which was totally reversed and inhibited by tolbutamide, a KATP channel blocker. Inhibition of LA metabolism by acyl-CoA synthetase inhibitor, triacsin C (10 μM), partially inhibited LA-induced opening of KATP channels by 64%. The non-FFA G protein-coupled receptor (GPR) 40 agonist, GW9508 (40 μM), induced an opening of KATP channels, which was similar to that induced by LA under triacsin C treatment. Blockade of protein kinases A and C did not influence the opening of KATP channels induced by LA and GW9508, indicating that these two protein kinase pathways are not involved in the action of LA on KATP channels. The present study demonstrates that LA induces hyperpolarization of MP by activating KATP channels via both intracellular metabolites and activation of GPR40. It indicates that not only intracellular metabolites of FFAs but also GPR40-mediated pathways take part in the inhibition of GSIS and β-cell dysfunction induced by FFAs.
TESTS OF BEHAVIORAL‐ECONOMIC ASSESSMENTS OF RELATIVE REINFORCER EFFICACY II: ECONOMIC COMPLEMENTS
Authors: Madden Gregory J. , Smethells John R. , Ewan Eric E. , Hursh Steven R.
Published: June 2008

This experiment was conducted to test the predictions of two behavioral‐economic approaches to quantifying relative reinforcer efficacy. The normalized demand analysis suggests that characteristics of averaged normalized demand curves may be used to predict progressive‐ratio breakpoints and peak responding. By contrast, the demand analysis holds that traditional measures of relative reinforcer efficacy (breakpoint, peak response rate, and choice) correspond to specific characteristics of non‐normalized demand curves. The accuracy of these predictions was evaluated in rats' responding for food or water: two reinforcers known to function as complements. Consistent with the first approach, predicted peak normalized response output values obtained under single‐schedule conditions ordinally predicted progressive‐ratio breakpoints and peak response rates obtained in a separate condition. combining the minimum‐needs hypothesis with the normalized demand analysis helped to interpret prior findings, but was less useful in predicting choice between food and water—two strongly complementary reinforcers. Predictions of the demand analysis had mixed success. Peak response outputs predicted from the non‐normalized water demand curves were significantly correlated with obtained peak responding for water in a separate condition, but none of the remaining three predicted correlations was statistically significant. The demand analysis fared better in predicting choice—relative consumption of food and water under single schedules of reinforcement predicted preference under concurrent schedules significantly better than chance.
AGE TRENDS IN STIMULUS OVERSELECTIVITY
Authors: McHugh Louise , Reed Phil
Published: June 2008

Stimulus overselectivity refers to the phenomenon whereby stimulus control over behavior is exerted only by a limited subset of the total number of stimuli present during discrimination learning. It often is displayed by individuals with autistic spectrum disorders or learning disabilities, but is not exclusive to those groups. The present studies investigated the impact of aging on stimulus control and overselectivity. Three age groups—18–22, 47–55, and 70–80 year olds—were studied in two experiments. All participants were trained on a simple discrimination task, randomly assigned to one of two conditions (either with or without a distractor task), and then tested for the emergence of overselectivity (Experiment 1). In Experiment 2 responding controlled by the overselected stimulus elements was reduced by introducing a verbal punisher. In subsequent tests, control of behavior by the previously underselected elements from Experiment 1 was enhanced across the two younger age groups but not the oldest group of participants. The results are discussed in relation to the attention‐deficit and overshadowing accounts of overselectivity.
EFFECTS OF DIFFERING RESPONSE‐FORCE REQUIREMENTS ON FOOD‐MAINTAINED RESPONDING IN CD‐1 MICE
Authors: Zarcone Troy J. , Chen Rong , Fowler Stephen C.
Published: June 2008

The effect of force requirements on response effort was examined using outbred (CD‐1) mice trained to press a disk with their snout. Lateral peak forces greater than 2 g were defined as threshold responses (i.e., all measured responses). Different force requirements were used to define criterion responses (a subclass of threshold responses) that exceeded the requirement. The reinforcer was sweetened, condensed milk, and it was delivered upon response termination. All mice were exposed to two ascending series of criterion force requirements (2, 4, 8, 16, and 32 g). Increasing the force requirement decreased criterion response rates, but increased threshold response rates. The time‐integral of force (area under the force‐time curve for individual responses, which is proportional to energy expenditure for each response) increased with the increase in the force requirement. These results conflict with the hypothesis that higher force requirements have aversive qualities and suggest that increased force requirements are more analogous to intermittent schedules of reinforcement. These data suggest that estimations of effort or energy expenditure should be measured independently of the force requirement. Individual differences in responding were found for the CD‐1 outbred stock.
SEASONAL VARIATION IN PIGEON BODY WEIGHT AND DELAYED MATCHING‐TO‐SAMPLE PERFORMANCE
Authors: Sargisson Rebecca J. , McLean Ian G. , Brown Glenn S. , White K. Geoffrey
Published: June 2008

The weights of 5 pigeons with free access to food, monitored over 3 calendar years in the laboratory, were found to fluctuate with season. All pigeons were at their heaviest in the winter and were lightest in the summer. Five different pigeons performed a standard delayed matching‐to‐sample task for 44 weeks from January to November. Their weights were held at 85% of their summer free‐feeding weights, making their predicted deprivation level higher in the winter relative to predicted winter free‐feeding weights. Slopes of forgetting functions fit to weekly response totals for each pigeon were shallower in winter, showing an improvement in accuracy with longer delays. Thus, delayed matching‐to‐sample performance may have been affected by the practice of maintaining the pigeons at a constant body weight throughout the calendar year.
Contributions of a Local Health Examination Survey to the Surveillance of Chronic and Infectious Diseases in New York City
Authors: Gwynn R. Charon , Garg Renu K. , Kerker Bonnie D. , Frieden Thomas R. , Thorpe Lorna E.
Published: June 2008

Objectives. We sought to evaluate the contribution of the New York City Health and Nutrition Examination Survey (NYC-HANES) to local public health surveillance.

Methods. Examination-diagnosed estimates of key health conditions from the 2004 NYC-HANES were compared with the National Health and Nutrition Examination Survey (NHANES) 2003–2004 national estimates. Findings were also compared with self-reported estimates from the Community Health Survey (CHS), an annually conducted local telephone survey.

Results. NYC-HANES estimated that among NYC adults, 25.6% had hypertension, 25.4% had hypercholesterolemia, 12.5% had diabetes, and 25.6% were obese. Compared with US adults, NYC residents had less hypertension and obesity but more herpes simplex 2 and environmental exposures (P < .05). Obesity was higher and hypertension was lower than CHS self-report estimates (P < .05). NYC-HANES and CHS self-reported diabetes estimates were similar (9.7% vs 8.7%).

Conclusions. NYC-HANES and national estimates differed for key chronic, infectious, and environmental indicators, suggesting the need for local data. Examination surveys may provide more accurate information for underreported conditions than local telephone surveys. Community-level health and nutrition examination surveys complement existing data, providing critical information for targeting local interventions.
Harold Fred Dorn and the First National Cancer Survey (1937-1939): The Founding of Modern Cancer Epidemiology
Authors: Lilienfeld David E.
Published: June 2008

The development of modern epidemiology, particularly cancer epidemiology, is often seen as a post–World War II phenomenon. However, the First National Cancer Survey, conducted from 1937 to 1939 as part of the newly formed National Cancer Institute's initial activities, provided the first data on the occurrence of cancer in the United States. This project was directed by a young sociologist, Harold Fred Dorn. Through Dorn, many of the methodological innovations in sociology, such as the use of surveys and observational study designs, were incorporated into modern epidemiology. I examine Dorn's training and early career in the context of the First National Cancer Survey as a means of investigating the beginnings of modern epidemiology.
Identifying Heterogeneity Among Injection Drug Users: A Cluster Analysis Approach
Authors: Shaw Souradet Y. , Shah Lena , Jolly Ann M. , Wylie John L.
Published: June 2008

Objectives. We used cluster analysis to subdivide a population of injection drug users and identify previously unknown behavioral heterogeneity within that population.

Methods. We applied cluster analysis techniques to data collected in a cross-sectional survey of injection drug users in Winnipeg, Manitoba. The clustering variables we used were based on receptive syringe sharing, ethnicity, and types of drugs injected.

Results. Seven clusters were identified for both male and female injection drug users. Some relationships previously revealed in our study setting, such as the known relationship between Talwin (pentazocine) and Ritalin (methylphenidate) use, injection in hotels, and hepatitis C virus prevalence, were confirmed through our cluster analysis approach. Also, relationships between drug use and infection risk not previously observed in our study setting were identified, an example being a cluster of female crystal methamphetamine users who exhibited high-risk behaviors but an absence or low prevalence of blood-borne pathogens.

Conclusions. Cluster analysis was useful in both confirming relationships previously identified and identifying new ones relevant to public health research and interventions.
Childhood Socioeconomic Position, Gender, Adult Body Mass Index, and Incidence of Type 2 Diabetes Mellitus Over 34 Years in the Alameda County Study
Authors: Maty Siobhan C. , Lynch John W. , Raghunathan Trivellore E. , Kaplan George A.
Published: June 2008

Objectives. We examined the association between childhood socioeconomic position and incidence of type 2 diabetes and the effects of gender and adult body mass index (BMI).

Methods. We studied 5913 participants in the Alameda County Study from 1965 to 1999 who were diabetes free at baseline (1965). Cox proportional hazards models estimated diabetes risk associated with childhood socioeconomic position and combined childhood socioeconomic position–adult BMI categories in pooled and gender-stratified samples. Demographic confounders and potential pathway components (physical inactivity, smoking, alcohol consumption, hypertension, depression, health care access) were included as covariates.

Results. Low childhood socioeconomic position was associated with excess diabetes risk, especially among women. Race and body composition accounted for some of this excess risk. The association between childhood socioeconomic position and diabetes incidence differed by adult BMI category in the pooled and women-only groups. Adjustment for race and behaviors attenuated the risk attributable to low childhood socioeconomic position among the obese group only.

Conclusions. Childhood socioeconomic position was a robust predictor of incident diabetes, especially among women. A cumulative risk effect was observed for both childhood socioeconomic position and adult BMI, especially among women.
Preliminary Evidence for an Emerging Nonmetropolitan Mortality Penalty in the United States
Authors: Cosby Arthur G. , Neaves Tonya T. , Cossman Ronald E. , Cossman Jeralynn S. , James Wesley L. , Feierabend Neal , Mirvis David M. , Jones Carol A. , Farrigan Tracey
Published: June 2008

We discovered an emerging non-metropolitan mortality penalty by contrasting 37 years of age-adjusted mortality rates for metropolitan versus nonmetropolitan US counties. During the 1980s, annual metropolitan–nonmetropolitan differences averaged 6.2 excess deaths per 100000 nonmetropolitan population, or approximately 3600 excess deaths; however, by 2000 to 2004, the difference had increased more than 10 times to average 71.7 excess deaths, or approximately 35 000 excess deaths. We recommend that research be undertaken to evaluate and utilize our preliminary findings of an emerging US nonmetropolitan mortality penalty.
Maternal Nonstandard Work Schedules and Adolescent Overweight
Authors: Miller Daniel P. , Han Wen-Jui
Published: June 2008

Objectives. We investigated whether nonstandard work schedules by mothers were associated with adolescent overweight.

Methods. We conducted multiple regression analyses using a sample of mother–child pairs (n=2353) from the National Longitudinal Survey of Youth to examine the association between the number of years mothers worked at nonstandard schedules and adolescent overweight at age 13 or 14 years. Separate analyses were also conducted by family income and family type.

Results. Child’s body mass index increased significantly if mothers worked either a few years or many years at nonstandard schedules. Risk of overweight was also significantly associated with 1 to 4 and 10 or more years of maternal nonstandard work schedules. In both cases, results were driven by those families with predicted incomes in the 2nd quartile (“near-poor”), with a few or many years of nonstandard work schedules also associated with increased risk of adolescent overweight in 2-parent families.

Conclusions. Results indicate the importance of the overlooked association between maternal nonstandard work schedules and adolescent overweight at age 13 or 14 years. Nonstandard work schedules among near-poor families and in 2-parent families may disrupt the work–family balance, affecting adolescent overweight.
Alternatives to the Randomized Controlled Trial
Authors: West Stephen G. , Duan Naihua , Pequegnat Willo , Gaist Paul , Des Jarlais Don C. , Holtgrave David , Szapocznik José , Fishbein Martin , Rapkin Bruce , Clatts Michael , Mullen Patricia Dolan
Published: June 2008

Public health researchers are addressing new research questions (e.g., effects of environmental tobacco smoke, Hurricane Katrina) for which the randomized controlled trial (RCT) may not be a feasible option.

Drawing on the potential outcomes framework (Rubin Causal Model) and Campbellian perspectives, we consider alternative research designs that permit relatively strong causal inferences. In randomized encouragement designs, participants are randomly invited to participate in one of the treatment conditions, but are allowed to decide whether to receive treatment.

In quantitative assignment designs, treatment is assigned on the basis of a quantitative measure (e.g., need, merit, risk). In observational studies, treatment assignment is unknown and presumed to be nonrandom. Major threats to the validity of each design and statistical strategies for mitigating those threats are presented.
A 6-Month Exercise Intervention Among Inactive and Overweight Favela-Residing Women in Brazil : The Caranguejo Exercise Trial
Authors: Alves João G. , Gale Catharine R. , Mutrie Nanette , Correia Jailson B. , Batty G. David
Published: June 2008

Objectives. We examined the viability and efficacy of a known quantity of exercise in facilitating weight loss among previously sedentary or irregularly active overweight and obese adult women residing in a slum (favela) in Brazil.

Methods. In this randomized controlled trial, 156 women were randomized to a control or intervention group (78 in each group). Exercise was supervised, consisting of three 50-minute aerobic sessions each week for 6 months.

Results. Ninety-one percent (71) of the participants in the intervention group completed 6 months of the exercise program. At 6 months, women in the treatment group showed significant reduction in weight (mean = −1.69 kg; 95% confidence interval [CI] = −2.36,−1.03) and body mass index (mean = −0.63 kg/m2; 95% CI = −0.97, −0.30) compared with controls (P for both < .001).

Conclusions. A moderately intense, structured exercise program resulted in modest weight loss in women when sustained for 6 months.
Effect of Hand Hygiene on Infectious Disease Risk in the Community Setting: A Meta-Analysis
Authors: Aiello Allison E. , Coulborn Rebecca M. , Perez Vanessa , Larson Elaine L.
Published: June 2008

To quantify the effect of hand-hygiene interventions on rates of gastrointestinal and respiratory illnesses and to identify interventions that provide the greatest efficacy, we searched 4 electronic databases for hand-hygiene trials published from January 1960 through May 2007 and conducted meta-analyses to generate pooled rate ratios across interventions (N=30 studies).

Improvements in hand hygiene resulted in reductions in gastrointestinal illness of 31% (95% confidence intervals [CI]=19%, 42%) and reductions in respiratory illness of 21% (95% CI=5%, 34%). The most beneficial intervention was hand-hygiene education with use of nonantibacterial soap. Use of antibacterial soap showed little added benefit compared with use of nonantibacterial soap.

Hand hygiene is clearly effective against gastrointestinal and, to a lesser extent, respiratory infections. Studies examining hygiene practices during respiratory illness and interventions targeting aerosol transmission are needed.
Association of Park Size, Distance, and Features With Physical Activity in Neighborhood Parks
Authors: Kaczynski Andrew T. , Potwarka Luke R. , Saelens Brian E.
Published: June 2008

Objectives. We studied whether park size, number of features in the park, and distance to a park from participants’ homes were related to a park being used for physical activity.

Methods. We collected observational data on 28 specific features from 33 parks. Adult residents in surrounding areas (n=380) completed 7-day physical activity logs that included the location of their activities. We used logistic regression to examine the relative importance of park size, features, and distance to participants’ homes in predicting whether a park was used for physical activity, with control for perceived neighborhood safety and aesthetics.

Results. Parks with more features were more likely to be used for physical activity; size and distance were not significant predictors. Park facilities were more important than were park amenities. Of the park facilities, trails had the strongest relationship with park use for physical activity.

Conclusions. Specific park features may have significant implications for park-based physical activity. Future research should explore these factors in diverse neighborhoods and diverse parks among both younger and older populations.
Coronary Heart Disease Deaths And Decreased Smoking Prevalence in Massachusetts, 1993–2003
Authors: Kabir Zubair , Connolly Gregory N. , Clancy Luke , Koh Howard K. , Capewell Simon
Published: June 2008

We used the previously validated IMPACT coronary heart disease (CHD) mortality model to estimate the CHD deaths attributable to reductions in smoking prevalence following the introduction of the Massachusetts Tobacco Control Program (MTCP) in 1993. A 29% and 31% decline in smoking prevalence and CHD mortality rates occurred, respectively (from 1993 to 2003). A total of 425 fewer CHD deaths, which generated approximately 3365 extra life-years, were attributable to decreased smoking prevalence. With these results in mind, a comprehensive tobacco control program should be sustained and supported.
Purchasing Behavior and Calorie Information at Fast-Food Chains in New York City, 2007
Authors: Bassett Mary T. , Dumanovsky Tamara , Huang Christina , Silver Lynn D. , Young Candace , Nonas Cathy , Matte Thomas D. , Chideya Sekai , Frieden Thomas R.
Published: June 2008

We surveyed 7318 customers from 275 randomly selected restaurants of 11 fast food chains. Participants purchased a mean of 827 calories, with 34% purchasing 1000 calories or more. Unlike other chains, Subway posted calorie information at point of purchase and its patrons more often reported seeing calorie infomation than patrons of other chains (32% vs 4%; P<.001); Subway patrons who saw calorie information purchased 52 fewer calories than did other Subway patrons (P<.01). Fast-food chains should display calorie information prominently at point of purchase, where it can be seen and used to inform purchases.