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Highlights • An ecological quality indicator correlated poorly with the flow regime. • Quantile regressions identified key limiting thresholds in flow parameters. • Flow-biota relations were stronger in upland reaches. • Caution is recommended in using the current biological indicator for e-flow design. Summary Since the implementation of the Water Framework Directive, the ecological status of European running waters has been evaluated using a set of harmonised ecological indicators that should guide conservation and restoration actions. Among these, the restoration of the natural flow regime (ecological flows) is considered indispensable for the achievement of the good ecological status, and yet the sensitivity of the current biological indicators to hydrologic parameters remains understudied. The Italian Star_ICMi well represents similar WFD indicators; it is a macroinvertebrate-based multimetric index officially adopted to assess the ecological status of running waters at the national level. Recent legislation has also included the Star_ICMi as one of the indicators used to assess and prescribe ecological flows in river reaches regulated by water abstraction. However, the relationship between river hydrology and the Star_ICMi index is so far virtually unknown. Using data from the Trentino – Alto Adige Alpine region, we first assessed the relationship between the Star_ICMi and synthetic descriptors of the physico-chemical (LIMeco) and morphological (MQI) status of respectively 280 and 184 river reaches. Then, we examined the relation between the Star_ICMi and a set of ecologically-relevant hydrologic parameters derived from discharge time-series measured at 21 hydrometric stations, representing both natural and regulated river reaches. Although the Star_ICMi showed significant and linear relationships with the physico-chemical character and, slightly, with the morphological quality of the reaches, its response to flow parameters appeared weak or non-existent when examined with linear models. Mixed quantile regressions allowed the identification of flow parameters that represented limiting factors for macroinvertebrate communities and the associated Star_ICMi scores. In particular, the index showed 'negative floors' where lower values were observed in reaches with large temporal variation in flow magnitude as well as frequent low and high flow events. The modelled quantiles also tracked the transition of the index from acceptable to unacceptable conditions. The results suggest that while the central tendency of the Star_ICMi index is not strongly influenced by river flow character, some key flow parameters represent limiting factors that allow the index to reach its lowest values, eventually 'pushing' the site towards unacceptable ecological conditions. The identification of limiting flow parameters can aid the setting of hydrologic thresholds over which ecological impairment is likely to occur. Overall, however, results imply caution is needed in using biological indicator like the Star_ICMi for the quantitative assessment and design of ecological flows. [ABSTRACT FROM AUTHOR]

Highlights: [•] A novel enzyme based method to sequence chitosan oligomers has been developed. [•] As compared to standard techniques like NMR only μg instead of mg amounts of oligomer are needed. [•] This novel method has been certified by mass spectrometry. [Copyright &y& Elsevier]

Abstract: The Fossellone Cave (San Felice Circeo - Central Italy) is one of the prehistoric sites that constitute the extraordinary group of Mount Circeo caves in the Southern Latium. The archaeological, geostratigraphical and ecological (paleoenvironmental) features of this settlement make it a natural centre of scientific interest. The study of the later part of the Middle Paleolithic sequence (layers F27–F23 of the stratigraphical deposit in the central slope), which started in 1989, has been an opportunity for analysis of the lithic assemblages belonging to late and final facies of the Mousterian complex. The lithic industries of F27–F23 layers indicate the transition from Middle to Upper Paleolithic and a change in occupancy from Homo neanderthalensis to Homo sapiens sapiens. The reconstruction of the environmental context and the systematic analysis of raw materials used for industry has been also carried out. The study of patina on artifacts indicates the effects of water circulation and abrasive action of wind in the cave. The evidence of a coloured powder (from yellow to ochre) on tools surfaces in squares β and γ of the digging grid of all layers studied suggests the choice of a specific place of the cave where this material was stored from the inhabitants of the cave. The mineral comes from an outcrop far from the Fossellone Cave, in the Mount Circeo area. The spatial distribution of the mineral coloured remains and the frequence of its occurrence in the archeological deposit of the Fossellone Cave suggests its intentional use by the Neanderthalian group inhabiting the area. [Copyright &y& Elsevier]

Abstract: The impact of a single hydropeaking event was studied in the Alpine stream Noce Bianco. Four stations were selected, one upstream and three, respectively, at 0.25, 6, and 8km downstream from a hydropower plant. We collected drifting invertebrates during a planned water release that increased the discharge 7-fold. At the onset of the hydropeaking wave the number of invertebrates lost from the riverbed per minute to the drift increased 9-fold at the first downstream station and the same effects propagated 8km downstream. The drift was composed mainly of aquatic insect larvae (Chironomidae, Plecoptera, Ephemeroptera Baetidae, and Psychodidae, with Chironomidae as the most abundant taxon at all stations) and partly by larval and adult riparian insects, and by Oligochaeta, which were particularly abundant at the station 6km downstream. We monitored drift for 30min from the start of the water release: peaks in drifting invertebrates occurred within 5–10min of the beginning of the hydropeaking wave, and most of the invertebrates were washed out within the first 15min of the water release. The different timeframes were possibly due to habitat preferences (most of the taxa that increased in the drift at the arrival of the wave were associated with algae and organic debris, which were washed off quickly by the increase in discharge) and/or behavioral adaptations (other taxa initially resisted the shear stress and began to drift with a delay of 5–10min). The temporal pattern and drift composition corresponded well with those reported in literature, and indicate that repeated high-flow events of similar magnitude cause considerable losses from benthic populations to drift. [Copyright &y& Elsevier]

Abstract: The rheological behaviour of the calcium salts of several commercial mannuronic and guluronic alginates in the time and frequency domain was assessed by quasi-static (uniaxial compression and compressive stress relaxation) and oscillatory dynamic tests. Both tests gave almost the same range (1–10%) of apparent linear viscoelasticity. Use of the Friedrich and Heymann model [Friedrich, Chr., & Heymann, L. (1988). Extension of a model for crosslinking polymer at the gel point. Journal of Rheology, 32, 235–241] allowed the transient responses of the network of alginate gels to be approximately characterised by a single relaxation function, its empirical parameters being independent of the experimental test provided that the applied strains were kept within the elastic and proportional limit. The linear interrelation between the material compressive (S α ) and shear (S β ) parameters was roughly checked using an independent estimate of the Poisson’s ratio via the NOL test [Warfield, R. W., Cuevas, J. E., & Barnet, F. R. (1970). Single specimen determination of Young’s and bulk moduli of polymers. Rheologica Acta, 9, 439–446] Since the information collected from simple compression or shear tests in the linear viscoelasticity regime was inter-convertible, the small amplitude oscillatory dynamic tests, which are simpler, quicker, less material consuming and thus less expensive than the quasi-static ones, might be recommended to discriminate between alginates of different origin and composition. [Copyright &y& Elsevier]

Abstract: In this work the production of an extra-cellular β-glucan by Botryosphaeria rhodina DABAC P82, previously studied in a conventional bench-top stirred bioreactor, was enhanced by resorting to two different strategies consisting of dispersing different volumetric fractions of paraffin oil into the culture broth or replacing the six flat-blade Rushton turbines with 45° pitched four-blade open style (fan) turbines with different impeller-to-vessel diameter ratios (D/T). Use of fan turbines with D/T =0.54 at a tip impeller speed of 1.4ms−1 resulted in less viscous culture broths and most advantageous values of the β-glucan concentration (18.7±0.3kgm−3), and yield coefficients for β-glucan on mycelial biomass formed (5.1±0.8gg−1) and specific power consumed (23.3±0.4gW−1). [Copyright &y& Elsevier]

Abstract: In the present paper, we propose a method of practical utility for calculating the aggregate claims distribution in a discrete framework. It is an approximated method but unlike the other approximated methods proposed in the literature: [•] the approximation concerns both the counting distribution and the convolution of the severity distributions; [•] the approximation does not consist in truncating the original distribution up to a given number of terms nor in replacing it with another distribution or a more general function (but simply in considering only the significant numerical realizations and in neglecting the others); [•] the resulting approximation of the aggregate claims distribution is lower than a prefixed maximum error (10−6 in our applications). In particular, the probability distribution and also the first three moments are exact with the prefixed maximum error. The proposed method does not require special assumptions on the counting distribution nor the identical distribution of the severity random variables and it does not incur in underflow and overflow computational problems. It proves to be more flexible, easier and cheaper than the (exact and approximated) methods using recursion and Fast Fourier Transform. We show some applications using both a Poisson distribution and a Generalized Pareto mixture of Poisson distributions as counting distribution. In addition to the specific application proposed in this paper, the method can be applied in many other (life and non-life) actuarial fields where the sum of discrete random variables and the calculation of compound distributions are involved. Besides, it can be extended in multivariate cases. [Copyright &y& Elsevier]

Abstract: This study investigated the modulation of angiotensin II-induced endothelial prostanoid release in rabbit aortic rings. Two cumulative dose response curves with 90-min washing interval were performed. Incubation with l-N G-nitroarginine methyl ester (l-NAME) 10−4 M increased angiotensin II maximal contractile response (E max). This effect was reversed by indomethacin 10−5 M, diphenyliodinum 10−5 M, Tempol 10−5 M or ascorbic acid 10−4 M in both cumulative dose response curves and by SQ 29548 10−6 M in the second cumulative dose response curve. When segments were treated with tetraethylamonium 10−3 M but not with glibenclamide 10−5 M during the washing period, l-NAME recovered its ability to enhance the E max in arteries incubated with SQ 29548. Conclusions: nitric oxide modulates angiotensin II-induced endothelial release of cyclooxygenase-dependent eicosanoids, one of which acts through thromboxane A2/prostaglandin H2 receptors and would decrease KCa channel activity. An increase in free radical production may account for the enhancement of such prostanoid release. Furthermore, it was found that in the present conditions, the release of the hyperpolarizing factor would improve in order to maintain the vascular tone. [Copyright &y& Elsevier]

The jellifying capacity of some alginate gels excreted by Azotobacter vinelandii DSM 576 was studied by oscillatory tests at alginate concentrations (c) of 1.0% and 1.5% w/w. Frequency dependence of the complex shear modulus (G*) permitted these gels to be discriminated in terms of their different orders of the relaxation function (α) and “gel stiffness” (Aα) values using Friedrich and Heymann theory [Journal of Rheology, 32 (1988) 235]. Of the samples tested that characterised by a guluronate content of 25% and a number-average molecular mass (Mn) of 263.4 kDa exhibited a gel stiffness at c=1% w/w of the same order of magnitude of that pertaining to alginates extracted from Macrocystis pyrifera or Lessonia nigrescens with greater guluronate contents (35–40%) but smaller number-average molecular masses (70–110 kDa) with about half of α.Whereas α was found to depend exponentially on the ratio of guluronate to mannuronate monad frequencies (NG/M) only, Aα was expressed as a power function of c, Mn, NG/M, and average G-block length (NG). The limited data available, as well as incomplete understanding of the real controlling factors for ionotropic gelation of alginates, made such empirical correlations just useful for a preliminary screening of alginates independently of their weed or microbial origin. [Copyright &y& Elsevier]

A series of sequential oscillatory dynamic tests was able to characterise the different stiffness of a few commercial high-quality Bologna sausages. Independently of their formulation, all samples were characterised as linear viscoelastic solids at strain amplitudes smaller than 1.3–8.1%.Using Friedrich and Heymann theory [J. Rheol. 32 (1988) 235], the study of the frequency dependence of the complex shear modulus (G*) permitted their protein network to be characterised in terms of a practically constant order of the relaxation function α (=0.10 ± 0.01) and a composition-dependent stiffness parameter (Aα). This was also confirmed by a validation test on another sample of Bologna sausage of different composition. By referring to fat-rich specimens Aα might be useful for distinguishing between products of different composition and sensory properties. [Copyright &y& Elsevier]

Secretory antibodies protect mucosal surfaces from ingested, inhaled and sexually transmitted pathogens. The polymeric immunoglobulin receptor (pIgR) transports antibodies across mucosal epithelia into external secretions. We and others have identified a region of the human polymeric immunoglobulin receptor gene (locus PIGR) that is sufficient for basal transcriptional activity. An E-Box motif, which binds transcription factors of the basic helix-loop-helix/leucine zipper (bHLH/zip) family, was identified as a major regulatory element in the PIGR gene promoter. Transient transfection of PIGR promoter reporter plasmids in intestinal epithelial cell (IEC) lines suggested that the transcription factors upstream stimulatory factor (USF) and c-Myc may exert opposing effects on PIGR promoter activity. Mutations within and flanking the E-Box that favored USF binding enhanced promoter activity, while mutations that favored c-Myc binding reduced promoter activity. Ectopic expression of USF1 or USF2 enhanced PIGR promoter activity, while exogenous c-Myc did not. Electrophoretic mobility shift assays (EMSA) demonstrated that USF1 and USF2 bound to the E-Box motif as homo- and heterodimers. Chromatin immunoprecipitation (ChIP) demonstrated that USF proteins bind the PIGR promoter in vivo, which is enriched in acetylated histones. E-Box motifs are commonly observed in promoters of genes that are highly expressed in the human colon. Genes that are down-regulated in colorectal cancer, including PIGR, frequently have non-canonical E-Boxes, while genes that are up-regulated in colorectal cancer generally have canonical E-Boxes. The results of our experiments may shed light on the mechanisms of dysregulated expression of pIgR in inflammatory bowel disease and colorectal cancer, diseases associated with aberrant expression of c-Myc. [Copyright &y& Elsevier]

A few reflections are made on the future strategies and approaches for combating infectious diseases of livestock, keeping into consideration public concern on food quality and availability. The policy of eradication of pathogens/diseases instead of vaccination has rendered livestock naive to certain pathogens and as a consequence susceptible to epidemic outbreaks, even more so as we have to conclude that outside attack is quite often difficult to control. Therefore, immunoprophylactic measures in livestock remain top priority and will in the future focus more on the induction of mucosal immunity and the activation of innate immunity. [Copyright &y& Elsevier]

• Novel geostatistical methods were applied to test the river continuum concept (RCC). • Downstream variation in invertebrate feeding groups did not form a continuum. • Stream-network models revealed high autocorrelation among flow-connected communities. • Local-scale variables were equally or more important than the downstream gradient. The River Continuum Concept (RCC) provided one of the first unifying frameworks in fluvial ecosystem theory. While the RCC predictions held in many empirical tests, other research highlighted how the model overlooked sources of heterogeneity at different scales e.g. the effects of tributaries. Disentangling these effects requires an assessment of variation in key ecosystem variables over the longitudinal and lateral dimension of river networks. However, so far, no empirical tests have employed a spatially explicit statistical approach to this assessment. Here, we show how recently-developed spatially-explicit models for river networks can be used to test predictions of the RCC whilst taking into account cross-scale sources of heterogeneity. We used macroinvertebrate data from 195 monitoring sites from 1st to 4th order streams spread across the Adige River network (NE Italy). We compared theoretical expectations with empirical semivariograms that incorporated network topology to assess the continuity and patchiness in the proportion of invertebrates functional feeding groups (FFG) over Euclidean and in-stream distances. Geostatistical stream-network models were then used to quantify the influence of the longitudinal gradient relative to local-scale water quality and land-use drivers, while accounting for network spatial autocorrelation. Patterns in the semivariograms based on flow-connected relationships were characterised by a nested structure associated with heterogeneity at multiple scales. Therefore, the longitudinal variation in FFG was better described by a patchy discontinuum rather than a gradient, implying that both in-stream processes and landscape factors influenced stream ecosystem function. The overall shift in FFG along the longitudinal profile was generally consistent with the RCC predictions, although the best models often included water quality and local land-use predictors. Stream-network models further indicated that up to 90% of residual variation (mean=50%) was accounted for by spatial autocorrelation, especially among flow-connected communities. Accounting for such autocorrelation not only improved model performance relative to non-spatial approaches, but indicated that most flow-connected communities were spatially correlated to some extent. This has clear implications for the assessment of the RCC tenets. This is the first test of the river continuum model that explicitly accounted for stream network topology and autocorrelation. Results indicated that in the Adige River, macroinvertebrates feeding groups exhibited heterogeneity along the longitudinal gradient, which appeared punctuated by local habitat transitions. Such transitions could be associated with artificial impoundments that alter the natural continuity of river processes, and we advocate the use of spatially explicit network models to test the RCC in more natural contexts. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Liver fibrosis commences with liver injury stimulating transforming growth factor beta (TGFβ) activation of hepatic stellate cells (HSCs), causing scarring and irreversible damage. TGFβ induces expression of the transcription factor Forkhead box S1 (FOXS1) in hepatocytes and may have a role in the pathogenesis of hepatocellular carcinoma (HCC). To date, no studies have determined how it affects HSCs. We analyzed human livers with cirrhosis, HCC, and a murine fibrosis model and found that FOXS1 expression is significantly higher in fibrotic livers but not in HCC. Next, we treated human LX2 HSC cells with TGFβ to activate fibrotic pathways, and FOXS1 mRNA was significantly increased. To study TGFβ-FOXS1 signaling, we developed human LX2 FOXS1 CRISPR KO and scrambled control HSCs. To determine differentially expressed gene transcripts controlled by TGFβ-FOXS1, we performed RNA-seq in the FOXS1 KO and control cells and over 400 gene responses were attenuated in the FOXS1 KO HSCs with TGFβ-activation. To validate the RNA-seq findings, we used our state-of-the-art PamGene PamStation kinase activity technology that measures hundreds of signaling pathways nonselectively in real time. Using our RNA-seq data, kinase activity data, and descriptive measurements, we found that FOXS1 controls pathways mediating TGFβ responsiveness, protein translation, and proliferation. Our study is the first to identify that FOXS1 may serve as a biomarker for liver fibrosis and HSC activation, which may help with early detection of hepatic fibrosis or treatment options for end-stage liver disease. [ABSTRACT FROM AUTHOR]

This review provides a detailed synthesis of the effects of glacier retreat and permafrost thaw on stream ecosystems in the European Alps. As a working framework, we present a conceptual model developed from an integration of current knowledge and understanding of the habitat and ecological shifts in Alpine streams caused by deglaciation. In our work, we depict how climate change and the loss of cryosphere trigger complex cascading effects on Alpine hydrology, as the main water sources shift from snow and glaciers to rock glaciers, groundwater, and precipitation. The associated changes in habitat conditions, such as channel stability, turbidity, temperature, nutrient loadings, and concentrations of legacy pollutants and trace elements are identified. These changes are followed by complex ecological shifts in the stream communities (microbial community, primary producers, invertebrates) and food webs, with a predicted loss of biotic diversity. Corresponding increases in taxa abundances, biomass, functional diversity, and in the complexity of food webs, are predicted to occur in the upper reaches of Alpine catchments in response to ameliorating climatic and habitat conditions. Finally, current knowledge gaps are highlighted as a basis for framing future research agendas. In particular, we call for an improved understanding of permafrost influence on Alpine headwaters, including the ecology of rock-glacier fed streams, as these streams are likely to become increasingly important for water supply in many glacier-free Alpine valleys in the near future. Unlabelled Image • We outline the changes in climate, glacier and permafrost occurring in the Alps. • We detail the effects of glacier retreat and rock glacier thaw on stream habitats. • We summarize the shifts in biotic communities and food webs in Alpine streams. • A conceptual model of the diverse effects of deglaciation on such streams is given. • Knowledge gaps and research priorities are examined, namely on rock glacier streams. [ABSTRACT FROM AUTHOR]

Abstract: Extraintestinal pathogenic Escherichia coli (ExPEC) contain tktA and tktB which code for transketolases involved in the pentose phosphate pathway. Recent studies demonstrated that a third gene coding for transketolase 1 (tkt1) was located in a pathogenicity island of avian and human ExPEC belonging to phylogenetic group B2. In the present study, in silico analysis of tkt1 revealed 68% and 69% identity with tktA and tktB, respectively, of ExPEC and 68% identity with tktA and tktB of E. coli MG1655. The translated tkt1 shared 69% and 68% identity with TktA and TktB proteins, respectively, of ExPEC and E. coli MG1655. Phylogenetically, it is shown that the three genes (tktA, tktB and tkt1) cluster in three different clades. Further analysis suggests that tkt1 has been acquired though horizontal gene transfer from plant-associated bacteria within the family Enterobacteriaceae. Virulence studies were performed in order to evaluate whether tkt1 played a role in avian pathogenic E. coli CH2 virulence in chickens. The evaluation revealed that mutant virulence was slightly lower based on LD50 when compared to the wild type during infection of chickens, but there were no significant differences when the two strains were compared based on the number of deaths and lesion scores. [Copyright &y& Elsevier]

This paper revives a fascinating debate: did a drought start before, during, or after the collapse of the Andean polity of Tiwanaku? Here we present an alternate age model that highlights the real issue: the data from Lake Orurillo, no matter the age model, are too imprecise to address the question. The authors neglect the significance of four-century error ranges (95% probability) for a drought that lasted a single century, according to their estimates. They are content to treat an imprecise correlation between drought and collapse as a causal relationship. Future efforts will require much greater attention to refining both paleoclimate and cultural chronologies, which is a necessary first step in understanding complex episodes of human–environment interaction. [ABSTRACT FROM AUTHOR]

Summary: The development of mucosal vaccines requires antigen delivery and adjuvant systems that can efficiently help in presenting vaccine antigens to the mucosal immune system. The outer membrane lipoprotein I (OprI) of Pseudomonas aeruginosa seems to possess both the quality to induce a non-specific immune response (adjuvant effect through its lipid tail) as well as the quality to facilitate uptake of the vaccine antigen by interacting with Toll-like receptor 2/4 (TLR2/4) on antigen-presenting cells (APC) and epithelial cells (adhesion effect). Here, we show for the first time the adhesion of OprI to epithelial cells of the trachea and small intestine of chickens. Adhesion could be seen on cryosections after in vitro as well as after in vivo incubation of the trachea and intestine. This proves the value of OprI as a fusion partner in mucosal protein vaccine development, which is especially important for poultry where mass vaccination is only possible by the respiratory or oral route. [Copyright &y& Elsevier]

• The SRs of cycling include sensation and feelings, natural and built environment, and materiality. • SRs of cycling vary in function of people's involvement in this mobility practice. • SRs of cycling vary in function of people's satisfaction for residential quality. • Urban cyclists evoke affective, bodily and material aspects of SRs. • Non users marginalise cycling to leisure and to 'other' places and people. Drawing on social representation theory and its connections with approaches to embodiment and social practice, the paper reports the result of a survey investigation (based on an on-line semi-structured questionnaire; N = 305) that studied the cognitive, emotional and sensorial components of the social representations of cycling. The general aim was to show how these theoretical frameworks can be used to identify the social-cultural barriers that might hamper the individual use of the bike for everyday purposes in addition to the mere infrastructural ones, and to assess possible variabilities in function of various factors of social-psychological (i.e. the perceived quality of the residential environment), experiential (i.e. linked to the individual daily practices), and geographical (i.e. big vs small urban areas of residence) nature. Results confirm the potentialities of these models to provide a deeper understanding of cycling practices, for example, suggesting, how, rather than being univocal and homogenous, people's shared conceptions regarding the topic investigated can vary depending on many of the factors considered, among which those of experiential and geographical nature seem to play a prominent role. The paper also discusses the implications for policies directed to fostering the adoption of more sustainable forms of transport within and outside urban areas, as well as their ability to broaden the theoretical understanding of cycling behaviour within social sciences in general. [ABSTRACT FROM AUTHOR]

Invasive species generate significant global environmental and economic costs and represent a particularly potent threat to freshwater systems. The biogeomorphic impacts of invasive aquatic and riparian species on river processes and landforms remain largely unquantified, but have the potential to generate significant sediment management issues within invaded catchments. Several species of invasive (non-native) crayfish are known to burrow into river banks and visual evidence of river bank damage is generating public concern and media attention. Despite this, there is a paucity of understanding of burrow distribution, biophysical controls and the potential significance of this problem beyond a small number of local studies at heavily impacted sites. This paper presents the first multi-catchment analysis of this phenomenon, combining existing data on biophysical river properties and invasive crayfish observations with purpose-designed field surveys across 103 river reaches to derive key trends. Crayfish burrows were observed on the majority of reaches, but burrowing tended to be patchy in spatial distribution, concentrated in a small proportion (< 10%) of the length of rivers surveyed. Burrow distribution was better explained by local bank biophysical properties than by reach-scale properties, and burrowed banks were more likely to be characterised by cohesive bank material, steeper bank profiles with large areas of bare bank face, often on outer bend locations. Burrow excavation alone has delivered a considerable amount of sediment to invaded river systems in the surveyed sites (3 t km − 1 impacted bank) and this represents a minimum contribution and certainly an underestimate of the absolute yield (submerged burrows were not recorded). Furthermore, burrowing was associated with bank profiles that were either actively eroding or exposed to fluvial action and/or mass failure processes, providing the first quantitative evidence that invasive crayfish may cause or accelerate river bank instability and erosion in invaded catchments beyond the scale of individual burrows. [ABSTRACT FROM AUTHOR]

Whether colostral leukocytes (CLs) of vaccinated dams influence the immune response of neonatal calves following vaccination against the same antigen as their respective dams remains unanswered. Therefore, we compared the induction of humoral and cellular immune responses after vaccination in calves that had received CL-free or maternal CL-enriched colostrum from a cell-free colostrum bank of nonvaccinated cows. Also, vaccinated calves that had received fresh maternal colostrum from their own dam were included in the study. Moreover, we analyzed whether the post-partum time of priming vaccination (day 2, 5 or 10) of the calves could influence the outcome of the immune responses. All calves received a booster vaccination 23 days after the priming vaccination. All calves showed only an increase in tetanus toxoid (TT)-specific antibodies and TT-induced proliferation after booster vaccination. Tetanus toxoid-specific antibody responses in calves increased immediately after booster vaccination, irrespective of whether or not their cell-free bank colostrum had been enriched with CLs from their own dam. Conversely, calves receiving their own plain dam colostrum displayed a later humoral response, due to colostral antibodies. After booster vaccination, calves of the CL-enriched colostrum group had a more pronounced antigen-specific proliferative response than the calves of the CL-free colostrum group. We propose that CLs might have a suppressive influence on the emergence of the TT-specific antibodies, but an enhancing effect on the TT-specific lymphocyte proliferation of newborn calves upon TT vaccination, which is dependent on the time point of the priming vaccination. [ABSTRACT FROM AUTHOR]

Nematode infections modulate the immune reaction of humans and livestock and may impair immune responses to non-parasitic antigens such as those present in vaccines. In this study, the relationship between antibodies directed against Ostertagia ostertagi, the economically most important nematode infection of cattle in temperate regions, and the magnitude and the kinetics of the antibody response to rabies vaccination was investigated in a commercial dairy herd of 46 cows. During the stabling period, all animals received a single intramuscular administration with a commercial inactivated rabies vaccine (Rabisin®, Merial). The serum antibody levels against O. ostertagi on day 0 were compared with antirabies IgM, IgA, IgG1, IgG2 and virus-neutralizing antibodies on days 0, 7, 14 and 21 after vaccination. In addition, to explore the potential effect of newly acquired O. ostertagi infections, the kinetics of the O. ostertagi antibody levels during the first 2 months after turnout on pasture were compared with concurrent changes in the rabies antibodies. During the stabling period the O. ostertagi antibody level tended to be positively associated with the magnitude, rate of increase and rate of decrease of the rabies antibodies. However, none of these associations were significant (P > 0.05). Over the first 2 months at pasture, an increase in O. ostertagi antibody level tended to be associated with a decrease in rabies IgG2 and IgM, but again these associations lacked statistical significance (P > 0.20). We conclude that the O. ostertagi antibody level in adult cattle over the housing period has no significant association with the antibody response to rabies vaccination. We recommend that future studies aiming to assess the relationship of nematode infections with humoral immune responses to vaccines are conducted on a larger scale and focus on the summer period when cattle are exposed continuously to nematode challenge from the pasture and hence are actively responding immunologically to nematode antigen exposure. [ABSTRACT FROM AUTHOR]

Abstract: Only a few vaccines are commercially available against intestinal infections since the induction of a protective intestinal immune response is difficult to achieve. For instance, oral administration of most proteins results in oral tolerance instead of an antigen-specific immune response. We have shown before that as a result of oral immunization of piglets with F4 fimbriae purified from pathogenic enterotoxigenic Escherichia coli (ETEC), the fimbriae bind to the F4 receptor (F4R) in the intestine and induce a protective F4-specific immune response. F4 fimbriae are very stable polymeric structures composed of some minor subunits and a major subunit FaeG that is also the fimbrial adhesin. In the present study, the mutagenesis experiments identified FaeG amino acids 97 (N to K) and 201 (I to V) as determinants for F4 polymeric stability. The interaction between the FaeG subunits in mutant F4 fimbriae is reduced but both mutant and wild type fimbriae behaved identically in F4R binding and showed equal stability in the gastro-intestinal lumen. Oral immunization experiments indicated that a higher degree of polymerisation of the fimbriae in the intestine was correlated with a better F4-specific mucosal immunogenicity. These data suggest that the mucosal immunogenicity of soluble virulence factors can be increased by the construction of stable polymeric structures and therefore help in the development of effective mucosal vaccines. [Copyright &y& Elsevier]

Abstract: NADPH oxidase is critically involved in increased blood pressure, vascular hypertrophy, inflammation and endothelial dysfunction in experimental and clinical hypertension. We hypothesized that NADPH oxidase might also play a role in the development of spontaneous aortic tone in spontaneously hypertensive rats (SHR). Wistar Kyoto rats (WKY) were used as normotensive controls. Tone was recorded under isometric conditions. NADPH oxidase activity was measured by both lucigenin luminescence and dihydroethidium fluorescence. p47phox protein was localized by immunohistochemistry. SHR (but not WKY rat) aortae showed spontaneous tone in the absence of exogenous vasoconstrictors as evidenced by a stronger relaxant effect of Ca2+-free sodium nitroprusside solution. This tone was enhanced in endothelium-denuded arteries and was inhibited by superoxide dismutase, apocynin, diphenylene iodonium and quercetin. Aortic NADPH oxidase activity, measured by both lucigenin luminescence and dihydroethidium fluorescence, was increased in SHR compared with WKY rats. Immunohistochemical analysis revealed a strong increase in p47phox expression in the medial layer in SHR. Taken together, the present results indicate that enhanced NADPH oxidase activity and, hence, NADPH driven O2 − production, is involved in the spontaneous aortic tone in SHR. This was associated with an increased expression of p47phox in the medial layer of the aorta. [Copyright &y& Elsevier]

Abstract: Plasmid DNA (pcDNA1::MOMP) expressing the major outer membrane protein (MOMP) of an avian Chlamydophila psittaci serovar D strain and recombinant MOMP (rMOMP) with or without the immunomodulating CpG oligonucleotides (CpG ON) were tested for their ability to elicit an immune response and to induce protection in turkeys against homologous challenge. Two CpG ON were chosen for in vivo application based on their in vitro capacity to stimulate the production of nitric oxide (NO) in chicken macrophages and their in vitro capacity to induce turkey lymphocyte proliferation. Priming and boosting of turkeys with pcDNA1::MOMP was able to prevent severe clinical signs and bacterial replication in a turkey model of C. psittaci infection. rMOMP boosting induced high antibody titers, but these did not correlate with the level of protection. Although the CpG ON induced a significant in vitro response, the presence of the CpG ON as an adjuvant generated no significant effect on the immune response or on the protective capacity of the tested vaccination methods. [Copyright &y& Elsevier]