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Find video protocols related to scientific articles indexed in Pubmed.
Microbial community dynamics and stability during an ammonia-induced shift to syntrophic acetate oxidation.
Appl. Environ. Microbiol.
PUBLISHED: 03-21-2014
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Anaerobic digesters rely on the diversity and distribution of parallel metabolic pathways mediated by complex syntrophic microbial communities to maintain robust and optimal performance. Using mesophilic swine waste digesters, we experimented with increased ammonia loading to induce a shift from aceticlastic methanogenesis to an alternative acetate-consuming pathway of syntrophic acetate oxidation. In comparison with control digesters, we observed shifts in bacterial 16S rRNA gene content and in functional gene repertoires over the course of the digesters' 3-year operating period. During the first year, under identical startup conditions, all bioreactors mirrored each other closely in terms of bacterial phylotype content, phylogenetic structure, and evenness. When we perturbed the digesters by increasing the ammonia concentration or temperature, the distribution of bacterial phylotypes became more uneven, followed by a return to more even communities once syntrophic acetate oxidation had allowed the experimental bioreactors to regain stable operation. The emergence of syntrophic acetate oxidation coincided with a partial shift from aceticlastic to hydrogenotrophic methanogens. Our 16S rRNA gene analysis also revealed that acetate-fed enrichment experiments resulted in communities that did not represent the bioreactor community. Analysis of shotgun sequencing of community DNA suggests that syntrophic acetate oxidation was carried out by a heterogeneous community rather than by a specific keystone population with representatives of enriched cultures with this metabolic capacity.
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Tumorgrafts as in vivo surrogates for women with ovarian cancer.
Clin. Cancer Res.
PUBLISHED: 01-07-2014
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Ovarian cancer has a high recurrence and mortality rate. A barrier to improved outcomes includes a lack of accurate models for preclinical testing of novel therapeutics.
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Do invasive species perform better in their new ranges?
Ecology
PUBLISHED: 07-18-2013
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A fundamental assumption in invasion biology is that most invasive species exhibit enhanced performance in their introduced range relative to their home ranges. This idea has given rise to numerous hypotheses explaining "invasion success" by virtue of altered ecological and evolutionary pressures. There are surprisingly few data, however, testing the underlying assumption that the performance of introduced populations, including organism size, reproductive output, and abundance, is enhanced in their introduced compared to their native range. Here, we combined data from published studies to test this hypothesis for 26 plant and 27 animal species that are considered to be invasive. On average, individuals of these 53 species were indeed larger, more fecund, and more abundant in their introduced ranges. The overall mean, however, belied significant variability among species, as roughly half of the investigated species (N=27) performed similarly when compared to conspecific populations in their native range. Thus, although some invasive species are performing better in their new ranges, the pattern is not universal, and just as many are performing largely the same across ranges.
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Limitations of lymph node ratio, evidence-based benchmarks, and the importance of a thorough lymph node dissection in melanoma.
Ann. Surg. Oncol.
PUBLISHED: 04-03-2013
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Stage III melanoma is currently stratified by number of lymph nodes (LNs) involved. However, given the variability of LN retrieval counts we hypothesize that lymph node ratio (LNR) may also provide prognostic information.
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Adaptive evolution during an ongoing range expansion: the invasive bank vole (Myodes glareolus) in Ireland.
Mol. Ecol.
PUBLISHED: 04-03-2013
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Range expansions are extremely common, but have only recently begun to attract attention in terms of their genetic consequences. As populations expand, demes at the wave front experience strong genetic drift, which is expected to reduce genetic diversity and potentially cause allele surfing, where alleles may become fixed over a wide geographical area even if their effects are deleterious. Previous simulation models show that range expansions can generate very strong selective gradients on dispersal, reproduction, competition and immunity. To investigate the effects of range expansion on genetic diversity and adaptation, we studied the population genomics of the bank vole (Myodes glareolus) in Ireland. The bank vole was likely introduced in the late 1920s and is expanding its range at a rate of ~2.5 km/year. Using genotyping-by-sequencing, we genotyped 281 bank voles at 5979 SNP loci. Fourteen sample sites were arranged in three transects running from the introduction site to the wave front of the expansion. We found significant declines in genetic diversity along all three transects. However, there was no evidence that sites at the wave front had accumulated more deleterious mutations. We looked for outlier loci with strong correlations between allele frequency and distance from the introduction site, where the direction of correlation was the same in all three transects. Amongst these outliers, we found significant enrichment for genic SNPs, suggesting the action of selection. Candidates for selection included several genes with immunological functions and several genes that could influence behaviour.
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Seroprevalence of Toxoplasma gondii in the Eurasian otter (Lutra lutra) in England and Wales.
Parasit Vectors
PUBLISHED: 03-13-2013
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Toxoplasma gondii is found on all continents and can infect all endothermic vertebrates. Toxoplasmosis is a globally important zoonosis with potentially devastating health impacts both for humans and a range of domestic and wild species. The World Health Organisation have repeatedly recommended the collection of accurate epidemiological data for T. gondii, yet despite recognised links between infection of wildlife, domestic animals and humans, seroprevalence in wild species is rarely monitored. Here, serological investigation using the Gold Standard Sabin-Feldman Dye Test was used to test for T. gondii in Eurasian otters (Lutra lutra) found dead, mainly as road-kill, in England and Wales. This is the first spatially widespread study of T. gondii in UK wildlife, and the first extensive survey of T. gondii in Eurasian otters, a sentinel species of fresh waters.
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Low molecular weight fibroblast growth factor-2 signals via protein kinase C and myofibrillar proteins to protect against postischemic cardiac dysfunction.
Am. J. Physiol. Heart Circ. Physiol.
PUBLISHED: 03-11-2013
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Among its many biological roles, fibroblast growth factor-2 (FGF2) acutely protects the heart from dysfunction associated with ischemia/reperfusion (I/R) injury. Our laboratory has demonstrated that this is due to the activity of the low molecular weight (LMW) isoform of FGF2 and that FGF2-mediated cardioprotection relies on the activity of protein kinase C (PKC); however, which PKC isoforms are responsible for LMW FGF2-mediated cardioprotection, and their downstream targets, remain to be elucidated. To identify the PKC pathway(s) that contributes to postischemic cardiac recovery by LMW FGF2, mouse hearts expressing only LMW FGF2 (HMWKO) were bred to mouse hearts not expressing PKC? (PKC?KO) or subjected to a selective PKC? inhibitor (?V(1-2)) before and during I/R. Hearts only expressing LMW FGF2 showed significantly improved postischemic recovery of cardiac function following I/R (P < 0.05), which was significantly abrogated in the absence of PKC? (P < 0.05) or presence of PKC? inhibition (P < 0.05). Hearts only expressing LMW FGF2 demonstrated differences in actomyosin ATPase activity as well as increases in the phosphorylation of troponin I and T during I/R compared with wild-type hearts; several of these effects were dependent on PKC? activity. This evidence indicates that both PKC? and PKC? play a role in LMW FGF2-mediated protection from cardiac dysfunction and that PKC? signaling to the contractile apparatus is a key step in the mechanism of LMW FGF2-mediated protection against myocardial dysfunction.
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Neighbourhood and consumer food environment is associated with dietary intake among Supplemental Nutrition Assistance Program (SNAP) participants in Fayette County, Kentucky.
Public Health Nutr
PUBLISHED: 03-06-2013
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The aim of the study was to determine the association between dietary outcomes and the neighbourhood food environment (street network distance from home to stores) and consumer food environment (Nutrition Environment Measurement Survey-Stores (NEMS-S) audit).
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Illness perception in bulimia nervosa.
J Health Psychol
PUBLISHED: 08-22-2011
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The study was designed to extend our understanding of illness perceptions in patients with bulimia nervosa (BN). Seventy-eight participants with BN or BN-type Eating Disorder Not Otherwise Specified (EDNOS-BN) completed the Revised Illness Perception Questionnaire (IPQ-R) (Moss-Morris et al., 2002). Clinical variables were also assessed. Participants experienced their ED as chronic, with serious consequences and high associated levels of anxiety and depression. The disorder was attributed primarily to psychological causes. The results indicate the perceived severity of BN, and high level of associated distress. These findings highlight the potential for targeting illness perceptions in treatment.
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Reconstitution of the human biome as the most reasonable solution for epidemics of allergic and autoimmune diseases.
Med. Hypotheses
PUBLISHED: 03-30-2011
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A wide range of hyperimmune-associated diseases plague post-industrial society, with a prevalence and impact that is staggering. Strong evidence points towards a loss of helminths from the ecosystem of the human body (the human biome) as the most important factor in this epidemic. Helminths, intestinal worms which are largely eradicated by elements of post-industrial culture including toilets and water treatment facilities, have an otherwise ubiquitous presence in vertebrates, and have co-evolved with the immune system. Not only do helminths discourage allergic and autoimmune reactions by diverting the immune system away from these pathologic processes and stimulating host regulatory networks, helminths release a variety of factors which down-modulate the immune system. A comprehensive view of hyperimmune-related disease based on studies in immunology, parasitology, evolutionary biology, epidemiology, and neurobiology indicates that the effects of biome depletion may not yet be fully realized, and may have an unexpectedly broad impact on many areas of human biology, including cognition. Fortunately, colonization with helminths results in a cure of numerous autoimmune and allergic diseases in laboratory rodents, and clinical studies in humans have indicated their utility for treatment of both multiple sclerosis and inflammatory bowel disease. Based on these considerations, commitment of considerable resources toward understanding the effects of "biome depletion" and systematically evaluating the most effective approach toward biome reconstitution is strongly encouraged.
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The prevalence of irritable bowel syndrome in outpatients with bulimia nervosa.
Int J Eat Disord
PUBLISHED: 02-14-2011
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This study examined the prevalence of irritable bowel syndrome (IBS) in patients with bulimia nervosa (BN), and the relationship between these disorders.
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Impacts of climate change on the worlds most exceptional ecoregions.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 01-24-2011
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The current rate of warming due to increases in greenhouse gas (GHG) emissions is very likely unprecedented over the last 10,000 y. Although the majority of countries have adopted the view that global warming must be limited to <2 °C, current GHG emission rates and nonagreement at Copenhagen in December 2009 increase the likelihood of this limit being exceeded by 2100. Extensive evidence has linked major changes in biological systems to 20th century warming. The "Global 200" comprises 238 ecoregions of exceptional biodiversity [Olson DM, Dinerstein E (2002) Ann Mo Bot Gard 89:199-224]. We assess the likelihood that, by 2070, these iconic ecoregions will regularly experience monthly climatic conditions that were extreme in 1961-1990. Using >600 realizations from climate model ensembles, we show that up to 86% of terrestrial and 83% of freshwater ecoregions will be exposed to average monthly temperature patterns >2 SDs (2?) of the 1961-1990 baseline, including 82% of critically endangered ecoregions. The entire range of 89 ecoregions will experience extreme monthly temperatures with a local warming of <2 °C. Tropical and subtropical ecoregions, and mangroves, face extreme conditions earliest, some with <1 °C warming. In contrast, few ecoregions within Boreal Forests and Tundra biomes will experience such extremes this century. On average, precipitation regimes do not exceed 2? of the baseline period, although considerable variability exists across the climate realizations. Further, the strength of the correlation between seasonal temperature and precipitation changes over numerous ecoregions. These results suggest many Global 200 ecoregions may be under substantial climatic stress by 2100.
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Pathogens, social networks, and the paradox of transmission scaling.
Interdiscip Perspect Infect Dis
PUBLISHED: 01-15-2011
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Understanding the scaling of transmission is critical to predicting how infectious diseases will affect populations of different sizes and densities. The two classic "mean-field" epidemic models-either assuming density-dependent or frequency-dependent transmission-make predictions that are discordant with patterns seen in either within-population dynamics or across-population comparisons. In this paper, we propose that the source of this inconsistency lies in the greatly simplifying "mean-field" assumption of transmission within a fully-mixed population. Mixing in real populations is more accurately represented by a network of contacts, with interactions and infectious contacts confined to the local social neighborhood. We use network models to show that density-dependent transmission on heterogeneous networks often leads to apparent frequency dependency in the scaling of transmission across populations of different sizes. Network-methodology allows us to reconcile seemingly conflicting patterns of within- and across-population epidemiology.
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Potential pathogenic bacteria in metalworking fluids and aerosols from a machining facility.
FEMS Microbiol. Ecol.
PUBLISHED: 10-18-2010
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The metalworking and machining industry utilizes recirculating metalworking fluids for integral aspects of the fabrication process. Despite the use of biocides, these fluids sustain substantial biological growth. Subsequently, the high-shear forces incurred during metalworking processing aerosolize bacterial cells and may cause dermatologic and respiratory effects in exposed workers. We quantified and identified the bacterial load for metalworking fluid and aerosol samples of a machining facility in the US Midwest during two seasons. To investigate the presence of potentially pathogenic bacteria in fluid and air, we performed 16S rRNA gene surveys. The concentration of total bacterial cells (including culturable and nonculturable cells) was relatively constant throughout the study, averaging 5.1 × 10? cells mL?¹ in the fluids and 4.8 × 10? cells m?³ in the aerosols. We observed bacteria of potential epidemiologic significance from several different bacterial phyla in both fluids and aerosols. Most notably, Alcaligenes faecalis was identified through both direct sequencing and culturing in every sample collected. Elucidating the bacterial community with gene surveys showed that metalworking fluids were the source of the aerosolized bacteria in this facility.
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Applying predator-prey theory to modelling immune-mediated, within-host interspecific parasite interactions.
Parasitology
PUBLISHED: 02-15-2010
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Predator-prey models are often applied to the interactions between host immunity and parasite growth. A key component of these models is the immune systems functional response, the relationship between immune activity and parasite load. Typically, models assume a simple, linear functional response. However, based on the mechanistic interactions between parasites and immunity we argue that alternative forms are more likely, resulting in very different predictions, ranging from parasite exclusion to chronic infection. By extending this framework to consider multiple infections we show that combinations of parasites eliciting different functional responses greatly affect community stability. Indeed, some parasites may stabilize other species that would be unstable if infecting alone. Therefore hosts immune systems may have adapted to tolerate certain parasites, rather than clear them and risk erratic parasite dynamics. We urge for more detailed empirical information relating immune activity to parasite load to enable better predictions of the dynamic consequences of immune-mediated interspecific interactions within parasite communities.
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Endotracheal tube biofilm inoculation of oral flora and subsequent colonization of opportunistic pathogens.
Int. J. Med. Microbiol.
PUBLISHED: 02-09-2010
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Endotracheal (ET) tubes accumulate a biofilm during use, which can harbor potentially pathogenic microorganisms. The enrichment of pathogenic strains in the biofilm may lead to ventilator-associated pneumonia (VAP) with an increased morbidity rate in intensive care units. We used quantitative PCR (qPCR) and gene surveys targeting 16S rRNA genes to quantify and identify the bacterial community to detect fastidious/nonculturable organisms present among extubated ET tubes. We collected eight ET tubes with intubation periods between 12 h and 23 d from different patients in a surgical and a medical intensive care unit. Our qPCR data showed that ET tubes were colonized within 24 h. However, the variation between patients was too high to find a positive correlation between the bacterial load and intubation period. We obtained 1263 near full-length 16S rRNA gene sequences from the diverse bacterial communities. Over 70% of these sequences were associated with genera of typical oral flora, while only 6% were associated with gastrointestinal flora. The most common genus identified was Streptococcus (348/1263), followed by Prevotella (179/1263), and Neisseria (143/1263) with the highest relative concentrations for ET tubes with short intubation periods, indicating oral inoculation of the ET tubes. Our study also shows that even though potentially pathogenic bacteria existed in ET tube biofilms within 24 h of intubation, a longer intubation period increases the opportunity for these organisms to proliferate. In the ET tube that was in place for 23 d, 95% of the sequences belonged to Pseudomonas aeruginosa, which is a bacterial pathogen that is known to out compete commensal bacteria in biofilms, especially during periods of antibiotic treatment. Harboring such pathogens in ET biofilms may increase the chance of VAP, and should be aggressively monitored and prevented.
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Bacteria isolated from parasitic nematodes--a potential novel vector of pathogens?
Environ Health
PUBLISHED: 12-21-2009
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Bacterial pathogens are ubiquitous in soil and water - concurrently so are free-living helminths that feed on bacteria. These helminths fall into two categories; the non-parasitic and the parasitic. The former have been the focus of previous work, finding that bacterial pathogens inside helminths are conferred survival advantages over and above bacteria alone in the environment, and that accidental ingestion of non-parasitic helminths can cause systemic infection in vertebrate hosts. Here, we determine the potential for bacteria to be associated with parasitic helminths. After culturing helminths from fecal samples obtained from livestock the external bacteria were removed. Two-hundred parasitic helminths from three different species were homogenised and the bacteria that were internal to the helminths were isolated and cultured. Eleven different bacterial isolates were found; of which eight were indentified. The bacteria identified included known human and cattle pathogens. We concluded that bacteria of livestock can be isolated in parasitic helminths and that this suggests a mechanism by which bacteria, pathogenic or otherwise, can be transmitted between individuals. The potential for helminths to play a role as pathogen vectors poses a potential livestock and human health risk. Further work is required to assess the epidemiological impact of this finding.
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Potentially pathogenic bacteria in shower water and air of a stem cell transplant unit.
Appl. Environ. Microbiol.
PUBLISHED: 07-06-2009
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Potential pathogens from shower water and aerosolized shower mist (i.e., shower aerosol) have been suggested as an environmental source of infection for immunocompromised patients. To quantify the microbial load in shower water and aerosol samples, we used culture, microscopic, and quantitative PCR methods to investigate four shower stalls in a stem cell transplant unit at Barnes-Jewish Hospital in St. Louis, MO. We also tested membrane-integrated showerheads as a possible mitigation strategy. In addition to quantification, a 16S rRNA gene sequencing survey was used to characterize the abundant bacterial populations within shower water and aerosols. The average total bacterial counts were 2.2 x 10(7) cells/liter in shower water and 3.4 x 10(4) cells/m(3) in shower aerosol, and these counts were reduced to 6.3 x 10(4) cells/liter (99.6% efficiency) and 8.9 x 10(3) cells/m(3) (82.4% efficiency), respectively, after membrane-integrated showerheads were installed. Potentially pathogenic organisms were found in both water and aerosol samples from the conventional showers. Most notable was the presence of Mycobacterium mucogenicum (99.5% identity) in the water and Pseudomonas aeruginosa (99.3% identity) in the aerosol samples. Membrane-integrated showerheads may protect immunocompromised patients from waterborne infections in a stem cell transplant unit because of efficient capture of vast numbers of potentially pathogenic bacteria from hospital water. However, an in-depth epidemiological study is necessary to investigate whether membrane-integrated showerheads reduce hospital-acquired infections. The microbial load in shower aerosols with conventional showerheads was elevated compared to the load in HEPA-filtered background air in the stem cell unit, but it was considerably lower than typical indoor air. Thus, in shower environments without HEPA filtration, the increase in microbial load due to shower water aerosolization would not have been distinguishable from anticipated variations in background levels.
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Comparison of social networks derived from ecological data: implications for inferring infectious disease dynamics.
J Anim Ecol
PUBLISHED: 05-21-2009
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1. Social network analyses tend to focus on human interactions. However, there is a burgeoning interest in applying graph theory to ecological data from animal populations. Here we show how radio-tracking and capture-mark-recapture data collated from wild rodent populations can be used to generate contact networks. 2. Both radio-tracking and capture-mark-recapture were undertaken simultaneously. Contact networks were derived and the following statistics estimated: mean-contact rate, edge distribution, connectance and centrality. 3. Capture-mark-recapture networks produced more informative and complete networks when the rodent density was high and radio-tracking produced more informative networks when the density was low. Different data collection methods provide more data when certain ecological characteristics of the population prevail. 4. Both sets of data produced networks with comparable edge (contact) distributions that were best described by a negative binomial distribution. Connectance and closeness were statistically different between the two data sets. Only betweenness was comparable. The differences between the networks have important consequences for the transmission of infectious diseases. Care should be taken when extrapolating social networks to transmission networks for inferring disease dynamics.
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Use of bioluminescent bacterial biosensors to investigate the role of free-living helminths as reservoirs and vectors of Salmonella.
Environ Microbiol Rep
PUBLISHED: 04-28-2009
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Free-living microbivorous helminths that consume pathogenic bacteria could offer an environmental refuge for those pathogens and also, in the case of accidental ingestion, could transmit food-borne pathogens to humans and livestock. We tested this hypothesis by comparing the survival of Salmonella bacteria that had been ingested by the helminth Caenorhabditis elegans with that of the bacteria alone, in a series of experiments to mimic harsh environmental conditions. Using lux gene technology to record the in vivo growth of Salmonella we found that when inside C. elegans, the Salmonella exhibited enhanced survival at pH 2 and 3, in the presence of chlorine and when exposed to UV irradiation, thereby providing an environmental refuge or reservoir for the bacteria. On inoculating laboratory mice with C. elegans that had been fed on bioluminescent Salmonella, real-time imaging showed that animals developed a systemic bacterial infection, indicating that free-living helminths could play a role as a vector of pathogens.
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Does elevated testosterone result in increased exposure and transmission of parasites?
Ecol. Lett.
PUBLISHED: 04-08-2009
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Male-biased infection is a common phenomenon in vertebrate-parasite systems and male-biased transmission has been experimentally demonstrated. One mechanism that is hypothesized to create male-biased transmission is the immuno-suppressive effect of testosterone because it increases susceptibility to infection. Testosterone also influences host behaviour and, consequently, may increase exposure to parasites. To test how testosterone could increase exposure and transmission, we undertook a longitudinal mark-recapture study where we experimentally elevated testosterone levels in wild male rodents. Individuals in control populations reduced the average number of contacts over the treatment period, while populations with experimentally elevated testosterone levels maintained the number of contacts between hosts. As a result, the transmission potential was higher in testosterone treated populations compared to controls. Our results indicated that males with high-testosterone levels alter the population-level contacts, producing different social networks and increasing transmission potential compared to those where testosterone is at background levels.
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Different evolutionary trajectories of European avian-like and classical swine H1N1 influenza A viruses.
J. Virol.
PUBLISHED: 03-18-2009
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In 1979, a lineage of avian-like H1N1 influenza A viruses emerged in European swine populations independently from the classical swine H1N1 virus lineage that had circulated in pigs since the Spanish influenza pandemic of 1918. To determine whether these two distinct lineages of swine-adapted A/H1N1 viruses evolved from avian-like A/H1N1 ancestors in similar ways, as might be expected given their common host species and origin, we compared patterns of nucleotide and amino acid change in whole genome sequences of both groups. An analysis of nucleotide compositional bias across all eight genomic segments for the two swine lineages showed a clear lineage-specific bias, although a segment-specific effect was also apparent. As such, there appears to be only a relatively weak host-specific selection pressure. Strikingly, despite each lineage evolving in the same species of host for decades, amino acid analysis revealed little evidence of either parallel or convergent changes. These findings suggest that although adaptation due to evolutionary lineages can be distinguished, there are functional and structural constraints on all gene segments and that the evolutionary trajectory of each lineage of swine A/H1N1 virus has a strong historical contingency. Thus, in the context of emergence of an influenza A virus strain via a host switch event, it is difficult to predict what specific polygenic changes are needed for mammalian adaptation.
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Generating super-shedders: co-infection increases bacterial load and egg production of a gastrointestinal helminth.
J R Soc Interface
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Co-infection by multiple parasites is common within individuals. Interactions between co-infecting parasites include resource competition, direct competition and immune-mediated interactions and each are likely to alter the dynamics of single parasites. We posit that co-infection is a driver of variation in parasite establishment and growth, ultimately altering the production of parasite transmission stages. To test this hypothesis, three different treatment groups of laboratory mice were infected with the gastrointestinal helminth Heligmosomoides polygyrus, the respiratory bacterial pathogen Bordetella bronchiseptica lux(+) or co-infected with both parasites. To follow co-infection simultaneously, self-bioluminescent bacteria were used to quantify infection in vivo and in real-time, while helminth egg production was monitored in real-time using faecal samples. Co-infection resulted in high bacterial loads early in the infection (within the first 5 days) that could cause host mortality. Co-infection also produced helminth super-shedders; individuals that chronically shed the helminth eggs in larger than average numbers. Our study shows that co-infection may be one of the underlying mechanisms for the often-observed high variance in parasite load and shedding rates, and should thus be taken into consideration for disease management and control. Further, using self-bioluminescent bacterial reporters allowed quantification of the progression of infection within the whole animal of the same individuals at a fine temporal scale (daily) and significantly reduced the number of animals used (by 85%) compared with experiments that do not use in vivo techniques. Thus, we present bioluminescent imaging as a novel, non-invasive tool offering great potential to be taken forward into other applications of infectious disease ecology.
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Role of multidetector computed tomography in the diagnosis and management of patients attending the rapid access chest pain clinic, The Scottish computed tomography of the heart (SCOT-HEART) trial: study protocol for randomized controlled trial.
David E Newby, Michelle C Williams, Andrew D Flapan, John F Forbes, Allister D Hargreaves, Stephen J Leslie, Steff C Lewis, Graham McKillop, Scott McLean, John H Reid, James C Sprat, Neal G Uren, Edwin J van Beek, Nicholas A Boon, Liz Clark, Peter Craig, Marcus D Flather, Chiara McCormack, Giles Roditi, Adam D Timmis, Ashma Krishan, Gillian Donaldson, Marlene Fotheringham, Fiona J Hall, Paul Neary, Louisa Cram, Sarah Perkins, Fiona Taylor, Hany Eteiba, Alan P Rae, Kate Robb, Dawn Barrie, Kim Bissett, Adelle Dawson, Scot Dundas, Yvonne Fogarty, Prasad Guntur Ramkumar, Graeme J Houston, Deborah Letham, Linda O'Neill, Stuart D Pringle, Valerie Ritchie, Thiru Sudarshan, Jonathan Weir-McCall, Alistair Cormack, Iain N Findlay, Stuart Hood, Clare Murphy, Eileen Peat, Barbara Allen, Andrew Baird, Danielle Bertram, David Brian, Amy Cowan, Nicholas L Cruden, Marc R Dweck, Laura Flint, Samantha Fyfe, Collette Keanie, Tom J MacGillivray, David S Maclachlan, Margaret MacLeod, Saeed Mirsadraee, Avril Morrison, Nicholas L Mills, Fiona C Minns, Alyson Phillips, Laura J Queripel, Nicholas W Weir, Fiona Bett, Frances Divers, Katie Fairley, Ashok J Jacob, Edith Keegan, Tricia White, John Gemmill, Margo Henry, James McGowan, Lorraine Dinnel, C Mark Francis, Dennis Sandeman, Ajay Yerramasu, Colin Berry, Heather Boylan, Ammani Brown, Karen Duffy, Alison Frood, Janet Johnstone, Kirsten Lanaghan, Ross Macduff, Martin MacLeod, Deborah McGlynn, Nigel McMillan, Laura Murdoch, Colin Noble, Victoria Paterson, Tracey Steedman, Nikolaos Tzemos.
Trials
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Rapid access chest pain clinics have facilitated the early diagnosis and treatment of patients with coronary heart disease and angina. Despite this important service provision, coronary heart disease continues to be under-diagnosed and many patients are left untreated and at risk. Recent advances in imaging technology have now led to the widespread use of noninvasive computed tomography, which can be used to measure coronary artery calcium scores and perform coronary angiography in one examination. However, this technology has not been robustly evaluated in its application to the clinic.
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A prescription for clinical immunology: the pills are available and ready for testing. A review.
Curr Med Res Opin
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Modern immunology has been extremely successful in elucidating many features of the immune system, but not in stemming pandemics of non-infectious, immune-related disease associated with industrialized populations. These pandemics involve a broad range of allergic, autoimmune, and inflammatory diseases, potentially including neuroinflammatory-associated disorders. It is the purpose of this review to outline the literature pointing toward the causes and potential treatments of these problems.
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Lymphocyte phenotypes in wild-caught rats suggest potential mechanisms underlying increased immune sensitivity in post-industrial environments.
Cell. Mol. Immunol.
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The immune systems of wild rats and of laboratory rats can been utilized as models of the human immune system in pre-industrial and post-industrial societies, respectively. In this study, lymphocyte phenotypes in wild rats were broadly characterized, and the results were compared to those obtained by us and by others using cells derived from various strains of laboratory rats. Although not expected, the production of regulatory T cells was not apparently different in wild rats compared to laboratory rats. On the other hand, differences in expression of markers involved in complement regulation, adhesion, signaling and maturation suggest increased complement regulation and decreased sensitivity in wild-caught rats compared to laboratory rats, and point toward complex differences between the maturation of T cells. The results potentially lend insight into the pathogenesis of post-industrial epidemics of allergy and autoimmune disease.
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Melanoma and rheumatoid arthritis (brief report).
Clin. Rheumatol.
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The aim of this study is to assess melanoma risk in rheumatoid arthritis (RA). A literature review was performed, retrieving observational studies over 1990-2010 that provided estimates of relative risk of melanoma associated with RA, compared to the general population. We generated standardized incidence ratio (SIR) estimates across all studies, first pooling the data and then performing a random-effects model to generate the SIRs. We retrieved 713 citations; after reviewing the titles and abstracts, 124 were further reviewed, and of these, 11 met our inclusion criteria for analysis. Pooling the data, there were a total of 601 melanomas that were observed over 1,351,061 patient-years of follow-up, or 4.4 cases per 10,000 years. The expected number of melanomas over this interval was 596.2 for a pooled SIR of 1.01 [95% confidence interval (CI), 0.93, 1.09]. Excluding the two patient groups that were known to be exposed to biologics, the SIR estimate was unchanged (1.01; 95 CI, 0.93, 1.10). Our random-effects model similarly indicated an SIR for melanoma of 0.95 [95% credible interval (CrI), 0.86, 1.03] overall and 0.95 (95% CrI, 0.86, 1.04) excluding the two patient groups that were known to be exposed to biologics. These results do not highlight an important increased risk for melanoma in RA patients over-all, compared to the general population. It is not clear whether the risk is different for patients specifically exposed to biologic agents, although data are relatively few. Further study, especially of RA patients with a past history of melanoma, is warranted.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

How does it work?

We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.