Evidence of Associations between Cytokine Genes and Subjective Reports of Sleep Disturbance in Oncology Patients and Their Family Caregivers

The purposes of this study were to identify distinct latent classes of individuals based on subjective reports of sleep disturbance; to examine differences in demographic, clinical, and symptom characteristics between the latent classes; and to evaluate for variations in pro- and anti-inflammatory cytokine genes between the latent classes. Among 167 oncology outpatients with breast, prostate, lung, or brain cancer and 85 of their FCs, growth mixture modeling (GMM) was used to identify latent classes of individuals based on General Sleep Disturbance Scale (GSDS) obtained prior to, during, and for four months following completion of radiation therapy. Single nucleotide polymorphisms (SNPs) and haplotypes in candidate cytokine genes were interrogated for differences between the two latent classes. Multiple logistic regression was used to assess the effect of phenotypic and genotypic characteristics on GSDS group membership. Two latent classes were identified: lower sleep disturbance (88.5%) and higher sleep disturbance (11.5%). Participants who were younger and had a lower Karnofsky Performance status score were more likely to be in the higher sleep disturbance class. Variation in two cytokine genes (i.e., IL6, NFKB) predicted latent class membership. Evidence was found for latent classes with distinct sleep disturbance trajectories. Unique genetic markers in cytokine genes may partially explain the interindividual heterogeneity characterizing these trajectories.     

Environmental temperatures and the incidence of food poisoning in England and Wales

The incidence of food poisoning in England and Wales has been increasing for many years and it is now a major public health problem. Superimposed on this general rising trend is a well-established tendency for the number of cases of food poisoning to rise during the summer when warm weather favours the multiplication of pathogenic micro-organisms. This paper shows that weekly notifications of food poisoning in England and Wales are strongly associated with environmental temperatures, but that there are some important time lags in this relationship. The number of cases of food poisoning in a given week was only weakly correlated with the temperature of that week and the one preceding it. This suggests that factors operating close to the point of consumption within or outside the home are not the principal cause of the rise in food poisoning associated with warm summer conditions. There was a much stronger association with temperatures 2–5 weeks earlier, pointing to the importance of factors operating earlier in the food production or distribution system. The results of this study suggest that the food poisoning problem requires action by food producers and distributors as well as by consumers. Received: 15 May 2000 / Revised: 17 October 2000 / Accepted: 18 October 2000     

PGRL is a major CD81-associated protein on lymphocytes and distinguishes a new family of cell surface proteins.

CD81 exerts a range of interesting effects on T cells including early thymocyte differentiation, LFA-1 activation, and provision of costimulation. To better understand the mechanisms by which CD81 influences T cell function we evaluated CD81 molecular complexes on T cells. The most prominent CD81-associated cell surface protein on thymocytes as well as a number of T cell and B cell lines has an apparent molecular mass of 75 kDa. The 75-kDa protein was purified and analyzed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry followed by postsource-decay profiling. p75 is a novel type I transmembrane protein of the Ig superfamily which is most similar to FPRP. We cloned and sequenced both human and mouse PG regulatory-like protein (PGRL) and characterized mouse PGRL expression in both lymphocytes and nonlymphoid tissues. The discovery of PGRL allows for the clustering of a small family of related proteins including PGRL, FPRP, V7/CD101, and IGSF3. Expression constructs containing various domains of PGRL with an epitope tag were coexpressed with CD81 and used to determine that the interaction of CD81 with PGRL requires the membrane distal Ig3-Ig4 domains of PGRL. Although it remains to be determined whether PGRL possesses PG regulatory functions, transwell chamber experiments show that PGs and CD81 coordinately regulate T cell motility.     

Identification of sodC encoding periplasmic [Cu,Zn]-superoxide dismutase in Salmonella

Abstract sodC , encoding [Cu,Zn]-cofactored Superoxide dismutase, once thought to be virtually confined to eukaryotes, has now been described in many Gram-negative pathogens that have their primary niche of colonization in the upper respiratory tract. Their role in host-parasite interactive biology is unknown. We here show that members of the major human and animal enteric pathogenic species Salmonella harbour a version of sodC most closely resembling that found in Brucella abortus . The enzyme it encodes is a novel candidate determinant of virulence in Salmonella , an intracellular pathogen potentially exposed to toxic oxygen free radicals within its intracellular niche.     

Molecular and genetic characterization of superoxide dismutase in Haemophilus influenzae type b

Oxygen free radicals present a serious potential threat to microbial survival, through their ability to inflict Indiscriminate damage on proteins and DNA. Superoxide dismutase (SOD, EC 1.15.1.1), among other oxygen-metabolizing enzymes, is essential to prevent these toxic molecules from accumulating in the bacterial cytosol during aerobic metabolism. The gene sodA, encoding manganese-containing SOD ([Mn]-SOD), has been cloned from a virulent strain of Haemophilus influenzae type b using degenerate oligonucleotides encoding regions of the gene conserved across different bacterial species. The gene product has been identified as [Mn]-SOD by its similarity at key amino acid residues to known examples of the enzyme, by expression of enzymatically active protein from cloned DNA expressed in Escherichia coli, and by demonstration that an in-frame deletion in the gene abolishes this activity. In contrast to the situation in E. coli, this [Mn]-SOD is the only active SOD detected in H. influenzae. In further contrast to E. coli, [Mn]-SOD gene expression in H. influenzae has been found to be only partially repressed under anaerobic conditions. When expressed in E. coli the gene is regulated by Fur and Fnr, and the promoter region, identified experimentally, has been found to contain nucleotide sequence motifs similar to the Fur- and Fnr-binding sequences of E. coli, suggesting the involvement of analogues of these aerobiosis- responsive activators in H. influenzae gene expression.     

Biodiversity and species interactions: extending Lotka–Volterra community theory

A new analysis of the nearly century‐old Lotka–Volterra theory allows us to link species interactions to biodiversity patterns, including: species abundance distributions, estimates of total community size, patterns of community invasibility, and predicted responses to disturbance. Based on a few restrictive assumptions about species interactions, our calculations require only that the community is sufficiently large to allow a mean‐field approximation. We develop this analysis to show how an initial assemblage of species with varying interaction strengths is predicted to sort out into the final community based on the species’ predicted target densities. The sorting process yields predictions of covarying patterns of species abundance, community size, and species interaction strengths. These predictions can be tested using enrichment experiments, examination of latitudinal and productivity gradients, and features of community assembly.