bluuebunny/crossref_metadata_2025_split huggingface dataset:
The chemokine network. I. How the genomic organization of chemokines contains clues for deciphering their functional complexity
Authors: Colobran R , Pujol-Borrell R , Armengol Ma P , Juan M 
Published: October 2008

SummaryChemokines are a superfamily of small structurally related cytokines that have evolved to form a complex network of proteins that typically regulate leucocyte traffic but also carry very diverse sets of immune and non-immune functions. Two general features of cytokines, redundancy and promiscuity, are particularly prominent in chemokines. In part, these properties result from repeated processes of gene duplication and diversification, which has led to the present complex genomic map of chemokines, which contains cases of non-allelic isoforms, copy number polymorphisms and classical allelic variation. This genomic complexity is compounded with pre-translational and post-translational mechanisms resulting in a complex network of proteins whose essential functions are maintained, constituting a remarkable case of robustness reminiscent of crucial metabolic pathways. This reflects the adaptation of a system under strong evolutive pressure, supporting the concept that the chemokine system is essential for the coordination, regulation and fine-tuning of the type of immune response. In this first review, we analyse currently available data on the chemokine superfamily, focusing on its complex genomic organization. Genes encoding essential inflammatory chemokines are grouped into defined chromosomal locations as clusters and miniclusters that, from the genetic point of view, can be considered single entities given their overall functions (many ligands of a cluster bind to a few shared receptors). We will try to interpret this genomic organization of chemokines in relation to the main functions acquired by each individual member or by each cluster. In a second review, we shall focus on the relationship of chemokine variability and disease susceptibility.
Therapeutic effect of a new immunosuppressive agent, everolimus, on interleukin-10 gene-deficient mice with colitis
Authors: Matsuda C , Ito T , Song J , Mizushima T , Tamagawa H , Kai Y , Hamanaka Y , Inoue M , Nishida T , Matsuda H , Sawa Y 
Published: October 2008

SummaryA limited number of therapeutic strategies are currently available for patients with inflammatory bowel disease (IBD). In particular, the maintenance therapy after remission in Crohn's disease (CD) is not satisfactory and new approaches are needed. Interleukin-10 gene-deficient (IL-10–/–) mice, a well-characterized experimental model of CD, develop severe chronic colitis due to an aberrant Th1 immune response. Everolimus, an inhibitor of the mammalian target of rapamycin (mTOR), a new immunosuppressive reagent, has been used successfully in animal models for heart, liver, lung and kidney transplantation. In the present study, we examined the efficacy of everolimus in the treatment of chronic colitis in an IL-10–/– mouse model. Everolimus was administered orally for a period of 4 weeks to IL-10–/– mice with clinical signs of colitis. The gross and histological appearances of the colon and the numbers, phenotype and cytokine production of lymphocytes were compared with these characteristics in a control group. The 4-week administration of everolimus resulted in a significant decrease in the severity of colitis, together with a significant reduction in the number of CD4+ T cells in the colonic lamina propria as well as IFN-γ production in colonic lymphocytes. Everolimus treatment of established colitis in IL-10–/– mice ameliorated the colitis, probably as a result of decreasing the number of CD4+ T cells in the colonic mucosa and an associated reduction in IFN-γ production.
Mannan-binding lectin may facilitate the clearance of circulating immune complexes − implications from a study on C2-deficient individuals
Authors: Saevarsdottir S , Steinsson K , Ludviksson B R , Grondal G , Valdimarsson H 
Published: October 2008

SummaryDeficiency of both mannan-binding lectin (MBL) and complement components C4 and C2 has been associated with increased risk of systemic lupus erythematosus (SLE). MBL can activate the complement system either through C4 and C2 or directly through C3. Circulating immune complexes (CICs) are believed to play a pathogenic role in SLE and MBL has been shown to bind certain forms of immunoglobulins, including IgM, IgG and IgA. Thus, MBL might promote CIC clearance. In order to evaluate this, six individuals with non-functional classical pathway due to the rare homozygous C2 deficiency were chosen, as the classical pathway is known to have a fundamental role in CIC clearance. Four of the six C2-deficient individuals had SLE, two of whom also had MBL deficiency. MBL serum levels and genotypes were compared with the serum levels of CICs, as measured by their content of kappa, lambda, IgM, IgA, IgG and C3 opsonization. The C2-deficient individuals had higher serum levels of CICs than 16 healthy controls (P &lt; 0·0001). Furthermore, an inverse association was observed between MBL and CIC levels in the C2-deficient individuals, which was strongest for IgM-CICs (r = − 0·84, P = 0·037). Moreover, C3 opsonization of the CICs correlated positively with MBL levels in the C2-deficient individuals (r = 0·89, P = 0·017). In conclusion, individuals with C2 deficiency have increased levels of CICs and MBL may facilitate their clearance. Defective CIC clearance might partly explain the increased risk of SLE associated with low MBL.
Lymphocyte–hepatic stellate cell proximity suggests a direct interaction
Authors: Muhanna N , Horani A , Doron S , Safadi R 
Published: October 2008

Summary
Recent functional research studies suggest an anti-fibrotic role for natural killer (NK) cells coupled with a profibrotic role for CD8 cells. However, the morphological cellular interplay between the different cell types is less clear. To investigate lymphocyte/hepatic stellate cell (HSC) interactions, hepatic fibrosis was induced by administering carbon tetrachloride (CCl4) intraperitoneally (i.p.) for 4 weeks in C57Bl/6 mice. Animals were killed at 0, 1, 2, 3 and 4 weeks. Liver sections were stained for Sirius red. Confocal microscopy was used to evaluate alpha smooth-muscle actin (αSMA) and lymphocyte subsets in liver sections. At weeks 0 and 4, liver protein extracts were assessed for αSMA by Western blotting and isolated liver lymphocytes as well as HSC were analysed by fluorescence activated cell sorter (FACS). Similar to the results obtained from classical Sirius red staining and αSMA blotting, analysis of liver sections by confocal microscopy revealed a marked and continuous accumulation of αSMA staining along sequential experimental check-points after administering CCl4. Although the number of all liver lymphocyte subsets increased following fibrosis induction, FACS analysis revealed an increase in the distribution of liver CD8 subsets and a decrease of CD4 T cells. Confocal microscopy showed a significant early appearance of CD8 and NK cells, and to a lesser extent CD4 T cells, appearing only from week 2. Lymphocytes were seen in proximity only to HSC, mainly in the periportal area and along fibrotic septa, suggesting a direct interaction. Notably, lymphocyte subsets were undetectable in naive liver sections. Freshly isolated HCS show high expression of major histocompatibility complex (MHC) class II and CD11c. In the animal model of hepatic fibrosis, lymphocytes infiltrate into the liver parenchyma and it is thought that they attach directly to activated HSC. Because HSCs express CD11c/class II molecules, interactions involving them might reflect that HSCs have an antigen-presenting capacity.
Expected future plague levels in a wildlife host under different scenarios of climate change
Authors: SNÄLL T. , BENESTAD R. E. , STENSETH N. C. 
Published: October 2008

AbstractWe predicted future plague and black‐tailed prairie dog dynamics in the North American prairies under different scenarios of climate change. A climate‐driven model for the joint dynamic of the host–parasite system was used. Projections for the regional climate were obtained through empirical–statistical downscaling of global climate scenarios generated by an ensemble of global climate models for the recent Fourth Assessment Report by the IPCC. The study shows the uncertainties involved in predicting future regional climate and climate‐driven population dynamics, but reveals that unchanged or lower levels of plague, leading to increased black‐tailed prairie dog colonies, can be expected. Less plague is particularly expected for scenarios that assume the highest emission of greenhouse gases associated with the greatest projected future warming. Moreover, under high‐emission scenarios, decreased probabilities of extremely high numbers of infected colonies are expected, along with decreased probabilities of extremely low total numbers of colonies. The assumed main underlying mechanism is an inhibiting effect of high temperatures on fleas (dispersal vector) and on flea‐mediated transmission of the disease‐causing bacterium. Our study highlights the importance of using dynamic ecological (here host–parasite) models together with ensembles of climate projections to investigate the responses of populations and parasites to a changed climate.
Mediterranean forest dynamics and forest bird distribution changes in the late 20th century
Authors: GIL‐TENA ASSU , BROTONS LLUÍS , SAURA SANTIAGO 
Published: October 2008

AbstractProcesses derived from global change such as land‐use changes, climate warming or modifications in the perturbation regime may have opposite effects on forest extent and structure with still unknown consequences on forest biodiversity at large spatial scales. In the present study, we aimed at determining forest dynamics associated with global change processes (forest spread, maturation and fire) that have driven the variation in forest bird distributions in Mediterranean forest ecosystems in recent years. The study was located in Catalonia (NE Spain) and used changes in richness of specialist and generalist forest bird species in the last 20 years of the 20th century as indicators of forest biodiversity change. Forest bird distribution changes showed strong spatial patterns and appeared to be related to population processes occurring beyond sampling units (10 km × 10 km squares). Forest maturation appeared as the most important driver of such changes because most of the studied species have a non‐Mediterranean origin and are associated with more mature forests. To a lower degree, forest spread also contributed to forest bird distribution changes whereas the impact of forest fires was not associated to a decrease in the richness of either group of forest species. Given the relatively coarse scale at which our study was conducted, caution should be taken when extrapolating our results to the possible future impacts of climate change on fire regime and forest bird distribution. Our results indicate that large‐scale forest maturation and spread due mainly to land abandonment in Catalonia has overridden the potentially negative effects of fires on forest bird distributions and are currently driving changes in forest biodiversity patterns across the region.
Variation in abundance across a species' range predicts climate change responses in the range interior will exceed those at the edge: a case study with North American beaver
Authors: JAREMA STACEY I. , SAMSON JASON , MCGILL BRIAN J. , HUMPHRIES MURRAY M. 
Published: October 2008

AbstractThe absence of information about how abundance varies across species' ranges restricts most modeling and monitoring of climate change responses to the range edge. We examine spatial variation in abundance across the northeastern range of North American beaver (Castor canadensis), evaluate the extent to which climate and nonclimate variables explain this variation, and use a species–climate envelope model that includes spatial variation in abundance to predict beaver abundance responses to projected climate change. The density of beaver colonies across Québec follows a roughly logistic pattern, with high but variable density across the southern portion of the province, a sharp decline in density at about 49°N, and a long tail of low density extending as far as 58°N. Several climate and nonclimate variables were strong predictors of variation in beaver density, but 97% of the variation explained by nonclimate variables could be accounted for by climate variables. Because of the peak and tail density pattern, beaver climate sensitivity (change in density per unit change in climate) was greatest in the interior and lowest at the edge of the range. Combining our best density–climate models with projections from general circulation models (GCM) predicts a relatively modest expansion of the species' northern range limit by 2055, but density increases in the range interior that far exceed those at the range edge. Thus, some of the most dramatic responses to climate change may be occurring in the core of species' ranges, far away from the edge‐of‐the‐range focus of most current modeling and monitoring efforts.
Cross‐scale environmental influences on migratory stopover behaviour
Authors: CALVERT ANNA M. , TAYLOR PHILIP D. , WALDE SANDRA 
Published: October 2008

AbstractMigratory species may be especially sensitive to climate change because their lifecycles are affected by dynamic ecological processes operating at global spatial scales. Insight into environmental effects upon en route decisions by migrants can therefore be a critical first step toward assessing their vulnerability to future climatic shifts. We extracted behaviour‐related parameters from a recent formulation of multistate mark–recapture models, and used them to evaluate the importance of variation in local weather and broad‐scale climate to decisions made by autumn passerine migrants at a coastal stopover site in Atlantic Canada. We found dramatic interannual fluctuations in the proportion of migrants that were transient (departing within a day of arrival), with annual average values ranging from 24% to 96% over the years 1996–2007. However, the relationships of stopover behaviour (transience and departure probability) to local weather (wind and precipitation) and to regional climatic fluctuations were similar across three distinct species groups and for birds of different fuel‐loads, indicating the potential for both immediate (day‐to‐day) and long‐term environmental influences (spanning several seasons). This cross‐scale approach contributes valuable information toward the conservation of migrants in the face of a changing climate by (i) quantifying environmental influences on stopover behaviour in broad temporal and geographic contexts, and (ii) demonstrating largely parallel interannual variation in stopover site‐use among birds with contrasting migratory timing and strategies.
Climate‐driven range extension of a sea urchin: inferring future trends by analysis of recent population dynamics
Authors: LING S. D. , JOHNSON C. R. , RIDGWAY K. , HOBDAY A. J. , HADDON M. 
Published: October 2008

AbstractPatterns of climate‐forced range shift in the marine environment are informed by investigating the population dynamics of an ecologically important sea urchin (Centrostephanus rodgersii– Diadematidae) across its newly extended range in Tasmania (southeastern Australia). A growth model of C. rodgersii is developed allowing estimation of a sea urchin age profile and, in combination with abundance data, we correlate the sea urchin population dynamic with respect to environmental signals across the range extension region. Growth patterns did not vary across the extension region; however, there was a strong pattern of decreasing sea urchin age with increasing distance from the historic range. The sequential poleward discovery of the sea urchin, a pattern of declining age and a general poleward reduction in abundance along the eastern Tasmanian coastline are consistent with a model of range extension driven by recent change in patterns of larval dispersal. We explore this hypothesis by correlating C. rodgersii population characteristics with respect to the East Australian Current (EAC), i.e. the chief vector for poleward larval dispersal, and reveal patterns of declining sea urchin age and abundance with increasing distance from this oceanic feature. Furthermore, C. rodgersii is generally limited to sites where average winter temperatures are warmer than the cold threshold for its larval development. Potential dispersal and physiological mechanisms defining the range extension appear to be strongly coupled to the EAC which has undergone recent poleward advance and resulted in coastal warming in eastern Tasmania. Predicted climate change conditions for this region will favour continued population expansion of C. rodgersii not only via atmospheric‐forced ocean warming, but also via ongoing intensification of the EAC driving continued poleward supply of larvae and heat.
A component of polysaccharide peptidoglycan complex on Lactobacillus induced an improvement of murine model of inflammatory bowel disease and colitis‐associated cancer
Authors: Matsumoto S. , Hara T. , Nagaoka M. , Mike A. , Mitsuyama K. , Sako T. , Yamamoto M. , Kado S. , Takada T. 
Published: October 2008

SummaryInterleukin‐6 (IL‐6)/signal transducer and activator of transcription 3 (STAT3) signals play key roles in the pathogenesis of inflammatory bowel disease (IBD). We previously described that both intact cells and a cell wall‐derived polysaccharide–peptidoglycan complex (PSPG) in a strain of lactobacillus [Lactobacillus casei Shirota (LcS)] inhibited IL‐6 production in lipopolysaccharide (LPS)‐stimulated lamina propria mononuclear cells (LPMCs) isolated from murine IBD. Diets with LcS improve murine IBD by suppression of IL‐6 synthesis in LPMCs. Moreover, LcS supplementation with fermented milk ameliorates disease activity in patients with active ulcerative colitis. Here, we focused on the specific roles of PSPG in LcS concerning their anti‐inflammatory actions. PSPG derived from LcS, and no other strain of lactobacilli, inhibited IL‐6 production in LPS‐stimulated murine IBD LPMCs. Purified PSPG‐I from LcS inhibited IL‐6 synthesis in LPS‐stimulated murine IBD LPMCs through the inhibition of nuclear factor‐κB. The anti‐IL‐6 action of LcS PSPG was abrogated by masking with monoclonal anti‐PSPG‐I. Furthermore, PSPG‐I‐negative L. casei strains (PSPG‐I‐negative mutant LcS: LCΔPSPG‐I, L. casei ATCC 334) did not inhibit IL‐6 production. Finally, we confirmed the effects of PSPG‐I on LcS in the models of both IBD and colitis‐associated cancer (CAC). In the IBD model, ingestion of LcS improved ileitis and inhibited activation of IL‐6/STAT3 signaling, while ingestion of the LCΔPSPG‐I strain did not. In the CAC model, treatment with LcS, but not the LCΔPSPG‐I strain, showed tumour‐suppressive effects with an inhibition of IL‐6 production in the colonic mucosa. These results suggested that a specific polysaccharide component in an L. casei strain plays a crucial role in its anti‐inflammatory actions in chronic intestinal inflammatory disorders.
Subversion of interleukin‐1‐mediated host defence by a nasal carrier strain of Staphylococcus aureus
Authors: Quinn Gerry A. , Tarwater Patrick M. , Cole Alexander M. 
Published: October 2008

Summary Staphylococcus aureus, a major source of nosocomial and community‐acquired infections, has a nasal carriage rate exceeding 25% in the human population. To elucidate host–pathogen interactions pertaining to nasal carriage, we examined the role of interleukin‐1 (IL‐1) in the colonization of human nasal epithelial cells (NEC) by a nasal carrier strain and a non‐carrier strain of S. aureus. Using an organotypic model of the nasal epithelium, we observed that inoculation with a non‐carrier strain of S. aureus induced production of IL‐1 from NEC, but the expression of this cytokine was significantly reduced when NEC were inoculated with a carrier strain. Moreover, both IL‐1α and IL‐1β significantly decreased the growth of the nasal carrier strain of S. aureus (P < 0·001, n = 17 to n = 25); however the growth of the non‐carrier strain was unaffected. Interestingly, it was found that several nasal carrier strains of S. aureus form quorum‐dependent biofilms, which can be partially inhibited when preincubated with IL‐1α. Taken together these data suggest that, although nasal carrier strains of S. aureus are sensitive to IL‐1, they display a significant colonization advantage by both preventing the host from expressing IL‐1 and elaborating a protective biofilm.
Effect of the essential oil addition on the oxidative stability of fried–salted peanuts
Authors: Olmedo Rubén , Nepote Valeria , Mestrallet Marta G. , Grosso Nelson R. 
Published: October 2008

SummaryThe objective of this study was to evaluate the antioxidant effect of essential oils on the oxidative stability of fried–salted peanuts. Fried–salted peanut (FP), fried–salted peanuts with butyl hydroxytoluene (FP‐BHT), and fried–salted peanuts with rosemary (FP‐R), oregano (FP‐O) and laurel (FP‐L) essential oils were prepared. Peroxide value (PV), p‐anisidine value (AV) and conjugated diene (CD) measurements, and descriptive analysis were carried out during 112 days of storage to determine the antioxidant effect of essential oils on product stability. FP with essential oils showed protection against the lipid oxidation process. PV and AV were higher during storage when compared with the other samples with essential oils. The oxidised and cardboard flavour intensities increased and the roasted peanutty flavour decreased much more in FP during storage than the other products studied. Laurel, oregano and BHT showed similar antioxidant activity and increased shelf‐life of FP. These essential oils could be used as natural antioxidants in foods with high lipid contents.
Biological response to different diets of fermented and unfermented mixtures of flour and cereal brans
Authors: Feddern Vivian , Badiale‐Furlong Eliana , De Souza‐Soares Leonor A. 
Published: October 2008

SummaryThe objective of this study was to biologically evaluate eight mixtures of flour and brans prepared with non‐conventional foods popularly denominated ‘multimixtures’, which differed from each other in terms of type of bran (wheat or rice), presence or absence of cassava leaf powder and submission or non‐submission to a solid‐state fermentation with Saccharomyces cerevisiae for 6 h/30 °C, utilising female Wistar/UFPEL rats. Biological indices determined were food efficiency ratio (FER), protein efficiency ratio (PER), net protein efficiency ratio (NPR) and in vivo digestibility. Liver, spleen and kidney specimens were collected at the end of the experiment. In vivo digestibility of diets containing multimixtures formulated with wheat bran was superior to diets containing rice bran, presenting values from 76.5% to 82.8%, which corresponds to up to 85% of casein digestibility. The results allowed the conclusion that fermentation tended to improve food efficiency, but did not influence in vivo digestibility.