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  • Author or Editor: M. T. Le x
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Abstract

The bacterial pathogen Campylobacter jejuni is the leading cause of foodborne gastroenteritis in the developed world, with the organism being transmitted by ingestion of contaminated and undercooked poultry. Exposure to acid is an inevitable stressor for C. jejuni during gastric passage, yet the effect of low pH on C. jejuni virulence is still poorly understood. Here, we investigate the effect of acid-shock on C. jejuni viability, gene expression and host-cell invasion. C. jejuni strain NCTC 11168 survived acid exposure at pH 3.5 and above for up to 30 min without a drop in viability, and this exposure induced the expression of flagellar genes transcribed from σ54-dependent promoters. Furthermore, acid-shock resulted in increased C. jejuni invasion of m-ICcl2 mouse small intestine crypt cells grown on transwells, but not when the cells were grown on flat-bottomed wells. This suggests that C. jejuni might be invading intestinal epithelial cells at the basolateral side, possibly after paracellular passage. We hypothesize that acid-shock prior to intestinal entry may serve as a signal that primes C. jejuni to express its virulence gene repertoire including flagellar motility genes, but this requires further study in the context of an appropriate colonization or disease model.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: M. Mason, J. Morris, V. Spate, C. Baskett, T. Nichols, T. Horsman, L. Le Marchand, L. Kolonel and S. Yukimoto

Abstract  

The measurement of dietary selenium intake in a free-living population using dietary recall techniques has been shown to be spurious. Consequently, in our laboratory, we have focused on the development of biologic monitors such as blood, nails, hair and urine. In this paper, we report on the neutron activation analysis of whole blood, plasma and nail specimens collected from 285 Caucasian subjects, all permanent residents of Hawaii, participating in a malignant melanoma trial. Correlations between monitors are presented and discussed in the context of selenium determinants and integration of selenium intake.

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Abstract  

There is currently great interest in iodine as a micro nutrient. Both high and low intakes have been associated with thyroid cancer incidence. Development of dietary iodine monitors is needed to supplement the use of dietary recall methods which have not been well validated for iodine. In this study, 30 pooled urine samples, from ethnic groups on various islands in the South Pacific, were analyzed for iodine using epithermal instrumental neutron activation analysis (EINAA).

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Abstract

Background and aims

Internet gaming disorder (IGD) has been recognized as a mental illness. Cognitive and emotional illness representations affect coping and health outcomes. Very little is known about such perceptions related to IGD, in both general and diseased populations. This study examined the psychometric properties of the Revised Illness Perception Questionnaire (IPQ-R) for IGD in a general population that included mostly non-cases while a small proportion of the sample was IGD cases.

Methods

An anonymous cross-sectional telephone survey was conducted in a random sample of 1,501 Chinese community-dwelling adults (41.3% male; mean age = 40.42, SD = 16.85) in Macao, China.

Results

The confirmatory factor analysis identified a modified 6-factor model (i.e., timeline cyclical, consequences, personal control, treatment control, illness coherence, and emotional representations) of 26 items that showed satisfactory model fit and internal consistency. Criterion-related validity was supported by the constructs' significant correlations with stigma (positive correlations: timeline cyclical, consequence, emotional representations; negative correlations: illness coherence). Ever-gamers, compared to never-gamers, reported higher mean scores in the subscales of personal control and illness coherence, and lower mean scores in time cyclical, consequence, and emotional representations. Among the sampled gamers, probable IGD cases were more likely than non-IGD cases to perceive IGD as cyclical and involved more negative emotions.

Conclusions

This study shows that the revised 26-item version of IPQ-R is a valid instrument for assessing illness representation regarding IGD in a general population of Chinese adults. It can be used in future research that examines factors of incidence and prevention related to IGD.

Open access
Journal of Radioanalytical and Nuclear Chemistry
Authors: P. Povinec, M. Pham, J. Sanchez-Cabeza, G. Barci-Funel, R. Bojanowski, T. Boshkova, W. Burnett, F. Carvalho, B. Chapeyron, I. Cunha, H. Dahlgaard, N. Galabov, L. Fifield, J. Gastaud, J. Geering, I. Gomez, N. Green, T. Hamilton, F. Ibanez, M. Ibn Majah, M. John, G. Kanisch, T. Kenna, M. Kloster, M. Korun, L. Liong Wee Kwong, J. La Rosa, S. Lee, I. Levy-Palomo, M. Malatova, Y. Maruo, P. Mitchell, I. Murciano, R. Nelson, A. Nouredine, J. Oh, B. Oregioni, G. Le Petit, H. Pettersson, A. Reineking, P. Smedley, A. Suckow, T. van der Struijs, P. Voors, K. Yoshimizu and E. Wyse

Abstract  

A reference material designed for the determination of anthropogenic and natural radionuclides in sediment, IAEA-384 (Fangataufa Lagoon sediment), is described and the results of certification are presented. The material has been certified for 8 radionuclides (40K, 60Co, 155Eu, 230Th, 238U, 238Pu, 239+240Pu and 241Am). Information values are given for 12 radionuclides (90Sr, 137Cs, 210Pb (210Po), 226Ra, 228Ra, 232Th, 234U, 235U, 239Pu, 240Pu and 241Pu). Less reported radionuclides include 228Th, 236U, 239Np and 242Pu. The reference material may be used for quality management of radioanalytical laboratories engaged in the analysis of radionuclides in the environment, as well as for the development and validation of analytical methods and for training purposes. The material is available from IAEA in 100 g units.

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