1,545 research outputs found
Eosinophils Are Important for Protection, Immunoregulation and Pathology during Infection with Nematode Microfilariae
Eosinophil responses typify both allergic and parasitic helminth disease. In helminthic disease, the role of eosinophils can be both protective in immune responses and destructive in pathological responses. To investigate whether eosinophils are involved in both protection and pathology during filarial nematode infection, we explored the role of eosinophils and their granule proteins, eosinophil peroxidase (EPO) and major basic protein-1 (MBP-1), during infection with Brugia malayi microfilariae. Using eosinophil-deficient mice (PHIL), we further clarify the role of eosinophils in clearance of microfilariae during primary, but not challenge infection in vivo. Deletion of EPO or MBP-1 alone was insufficient to abrogate parasite clearance suggesting that either these molecules are redundant or eosinophils act indirectly in parasite clearance via augmentation of other protective responses. Absence of eosinophils increased mast cell recruitment, but not other cell types, into the broncho-alveolar lavage fluid during challenge infection. In addition absence of eosinophils or EPO alone, augmented parasite-induced IgE responses, as measured by ELISA, demonstrating that eosinophils are involved in regulation of IgE. Whole body plethysmography indicated that nematode-induced changes in airway physiology were reduced in challenge infection in the absence of eosinophils and also during primary infection in the absence of EPO alone. However lack of eosinophils or MBP-1 actually increased goblet cell mucus production. We did not find any major differences in cytokine responses in the absence of eosinophils, EPO or MBP-1. These results reveal that eosinophils actively participate in regulation of IgE and goblet cell mucus production via granule secretion during nematode-induced pathology and highlight their importance both as effector cells, as damage-inducing cells and as supervisory cells that shape both innate and adaptive immunity
Effects of deletion of the Streptococcus pneumoniae lipoprotein diacylglyceryl transferase gene lgt on ABC transporter function and on growth in vivo
Lipoproteins are an important class of surface associated proteins that have diverse roles and frequently are involved in the virulence of bacterial pathogens. As prolipoproteins are attached to the cell membrane by a single enzyme, prolipoprotein diacylglyceryl transferase (Lgt), deletion of the corresponding gene potentially allows the characterisation of the overall importance of lipoproteins for specific bacterial functions. We have used a Δlgt mutant strain of Streptococcus pneumoniae to investigate the effects of loss of lipoprotein attachment on cation acquisition, growth in media containing specific carbon sources, and virulence in different infection models. Immunoblots of triton X-114 extracts, flow cytometry and immuno-fluorescence microscopy confirmed the Δlgt mutant had markedly reduced lipoprotein expression on the cell surface. The Δlgt mutant had reduced growth in cation depleted medium, increased sensitivity to oxidative stress, reduced zinc uptake, and reduced intracellular levels of several cations. Doubling time of the Δlgt mutant was also increased slightly when grown in medium with glucose, raffinose and maltotriose as sole carbon sources. These multiple defects in cation and sugar ABC transporter function for the Δlgt mutant were associated with only slightly delayed growth in complete medium. However the Δlgt mutant had significantly reduced growth in blood or bronchoalveolar lavage fluid and a marked impairment in virulence in mouse models of nasopharyngeal colonisation, sepsis and pneumonia. These data suggest that for S. pneumoniae loss of surface localisation of lipoproteins has widespread effects on ABC transporter functions that collectively prevent the Δlgt mutant from establishing invasive infection
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A vector-valued ground motion intensity measure incorporating normalized spectral area
A vector-valued intensity measure is presented, which incorporates a relative measure represented by the normalized spectral area. The proposed intensity measure is intended to have high correlation with specific relative engineering demand parameters, which collectively can provide information regarding the damage state and collapse potential of the structure. Extensive dynamic analyses are carried out on a single-degree-of-freedom system with a modified Clough–Johnston hysteresis model, using a dataset of 40 ground motions, in order to investigate the proposed intensity measure characteristics. Response is expressed using the displacement ductility, and the normalized hysteretic energy, both of which are relative engineering demand parameters. Through regression analysis the correlation between the proposed intensity measure and the engineering demand parameters is evaluated. Its domain of applicability is investigated through parametric analysis, by varying the period and the strain-hardening stiffness. Desirable characteristics such as efficiency, sufficiency, and statistical independence are examined. The proposed intensity measure is contrasted to another one, with respect to its correlation to the engineering demand parameters. An approximate procedure for estimating the optimum normalized spectral area is also presented. It is demonstrated that the proposed intensity measure can be used in intensity-based assessments, and, with proper selection of ground motions, in scenario-based assessments
BPGA- an ultra-fast pan-genome analysis pipeline
Recent advances in ultra-high-throughput sequencing technology and metagenomics have led to a
paradigm shift in microbial genomics from few genome comparisons to large-scale pan-genome studies
at different scales of phylogenetic resolution. Pan-genome studies provide a framework for estimating
the genomic diversity of the dataset, determining core (conserved), accessory (dispensable) and
unique (strain-specific) gene pool of a species, tracing horizontal gene-flux across strains and providing
insight into species evolution. The existing pan genome software tools suffer from various limitations
like limited datasets, difficult installation/requirements, inadequate functional features etc. Here we
present an ultra-fast computational pipeline BPGA (Bacterial Pan Genome Analysis tool) with seven
functional modules. In addition to the routine pan genome analyses, BPGA introduces a number of
novel features for downstream analyses like core/pan/MLST (Multi Locus Sequence Typing) phylogeny,
exclusive presence/absence of genes in specific strains, subset analysis, atypical G + C content analysis
and KEGG & COG mapping of core, accessory and unique genes. Other notable features include
minimum running prerequisites, freedom to select the gene clustering method, ultra-fast execution,
user friendly command line interface and high-quality graphics outputs. The performance of BPGA has
been evaluated using a dataset of complete genome sequences of 28 Streptococcus pyogenes strains
Comparative analysis of inflamed and non-inflamed colon biopsies reveals strong proteomic inflammation profile in patients with ulcerative colitis
<p>Abstract</p> <p>Background</p> <p>Accurate diagnostic and monitoring tools for ulcerative colitis (UC) are missing. Our aim was to describe the proteomic profile of UC and search for markers associated with disease exacerbation. Therefore, we aimed to characterize specific proteins associated with inflamed colon mucosa from patients with acute UC using mass spectrometry-based proteomic analysis.</p> <p>Methods</p> <p>Biopsies were sampled from rectum, sigmoid colon and left colonic flexure from twenty patients with active proctosigmoiditis and from four healthy controls for proteomics and histology. Proteomic profiles of whole colonic biopsies were characterized using 2D-gel electrophoresis, and peptide mass fingerprinting using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was applied for identification of differently expressed protein spots.</p> <p>Results</p> <p>A total of 597 spots were annotated by image analysis and 222 of these had a statistically different protein level between inflamed and non-inflamed tissue in the patient group. Principal component analysis clearly grouped non-inflamed samples separately from the inflamed samples indicating that the proteomic signature of colon mucosa with acute UC is strong. Totally, 43 individual protein spots were identified, including proteins involved in energy metabolism (triosephosphate isomerase, glycerol-3-phosphate-dehydrogenase, alpha enolase and L-lactate dehydrogenase B-chain) and in oxidative stress (superoxide dismutase, thioredoxins and selenium binding protein).</p> <p>Conclusions</p> <p>A distinct proteomic profile of inflamed tissue in UC patients was found. Specific proteins involved in energy metabolism and oxidative stress were identified as potential candidate markers for UC.</p
Stepped care targeting psychological distress in head and neck and lung cancer patients: a randomized clinical trial
<p>Abstract</p> <p>Background</p> <p>Psychological distress is common in cancer survivors. Although there is some evidence on effectiveness of psychosocial care in distressed cancer patients, referral rate is low. Lack of adequate screening instruments in oncology settings and insufficient availability of traditional models of psychosocial care are the main barriers. A stepped care approach has the potential to improve the efficiency of psychosocial care. The aim of the study described herein is to evaluate efficacy of a stepped care strategy targeting psychological distress in cancer survivors.</p> <p>Methods/design</p> <p>The study is designed as a randomized clinical trial with 2 treatment arms: a stepped care intervention programme versus care as usual. Patients treated for head and neck cancer (HNC) or lung cancer (LC) are screened for distress using OncoQuest, a computerized touchscreen system. After stratification for tumour (HNC vs. LC) and stage (stage I/II vs. III/IV), 176 distressed patients are randomly assigned to the intervention or control group. Patients in the intervention group will follow a stepped care model with 4 evidence based steps: 1. Watchful waiting, 2. Guided self-help via Internet or a booklet, 3. Problem Solving Treatment administered by a specialized nurse, and 4. Specialized psychological intervention or antidepressant medication. In the control group, patients receive care as usual which most often is a single interview or referral to specialized intervention. Primary outcome is the Hospital Anxiety and Depression Scale (HADS). Secondary outcome measures are a clinical level of depression or anxiety (CIDI), quality of life (EQ-5D, EORTC QLQ-C30, QLQ-HN35, QLQ-LC13), patient satisfaction with care (EORTC QLQ-PATSAT), and costs (health care utilization and work loss (TIC-P and PRODISQ modules)). Outcomes are evaluated before and after intervention and at 3, 6, 9 and 12 months after intervention.</p> <p>Discussion</p> <p>Stepped care is a system of delivering and monitoring treatments, such that effective, yet least resource-intensive, treatment is delivered to patients first. The main aim of a stepped care approach is to simplify the patient pathway, provide access to more patients and to improve patient well-being and cost reduction by directing, where appropriate, patients to low cost (self-)management before high cost specialist services.</p> <p>Trial registration</p> <p>NTR1868</p
Immune response of healthy horses to DNA constructs formulated with a cationic lipid transfection reagent
Background Deoxyribonucleic acid (DNA) vaccines are used for experimental
immunotherapy of equine melanoma. The injection of complexed linear DNA
encoding interleukin (IL)-12/IL-18 induced partial tumour remission in a
clinical study including 27 grey horses. To date, the detailed mechanism of
the anti-tumour effect of this treatment is unknown. Results In the present
study, the clinical and cellular responses of 24 healthy horses were monitored
over 72 h after simultaneous intradermal and intramuscular application of
equine IL-12/IL-18 DNA (complexed with a transfection reagent) or comparative
substances (transfection reagent only, nonsense DNA, nonsense DNA depleted of
CG). Although the strongest effect was observed in horses treated with
expressing DNA, horses in all groups treated with DNA showed systemic
responses. In these horses treated with DNA, rectal temperatures were elevated
after treatment and serum amyloid A increased. Total leukocyte and neutrophil
counts increased, while lymphocyte numbers decreased. The secretion of tumour
necrosis factor alpha (TNFα) and interferon gamma (IFNγ) from peripheral
mononuclear blood cells ex vivo increased after treatments with DNA, while
IL-10 secretion decreased. Horses treated with DNA had significantly higher
myeloid cell numbers and chemokine (C-X-C motif) ligand (CXCL)-10 expression
in skin samples at the intradermal injection sites compared to horses treated
with transfection reagent only, suggesting an inflammatory response to DNA
treatment. In horses treated with expressing DNA, however, local CXCL-10
expression was highest and immunohistochemistry revealed more intradermal
IL-12-positive cells when compared to the other treatment groups. In contrast
to non-grey horses, grey horses showed fewer effects of DNA treatments on
blood lymphocyte counts, TNFα secretion and myeloid cell infiltration in the
dermis. Conclusion Treatment with complexed linear DNA constructs induced an
inflammatory response independent of the coding sequence and of CG motif
content. Expressing IL-12/IL-18 DNA locally induces expression of the
downstream mediator CXCL-10. The grey horses included appeared to display an
attenuated immune response to DNA treatment, although grey horses bearing
melanoma responded to this treatment with moderate tumour remission in a
preceding study. Whether the different immunological reactivity compared to
other horses may contributes to the melanoma susceptibility of grey horses
remains to be elucidated
Search for rare quark-annihilation decays, B --> Ds(*) Phi
We report on searches for B- --> Ds- Phi and B- --> Ds*- Phi. In the context
of the Standard Model, these decays are expected to be highly suppressed since
they proceed through annihilation of the b and u-bar quarks in the B- meson.
Our results are based on 234 million Upsilon(4S) --> B Bbar decays collected
with the BABAR detector at SLAC. We find no evidence for these decays, and we
set Bayesian 90% confidence level upper limits on the branching fractions BF(B-
--> Ds- Phi) Ds*- Phi)<1.2x10^(-5). These results
are consistent with Standard Model expectations.Comment: 8 pages, 3 postscript figues, submitted to Phys. Rev. D (Rapid
Communications
The global burden of tuberculosis: results from the Global Burden of Disease Study 2015
Background:
An understanding of the trends in tuberculosis incidence, prevalence, and mortality is crucial to tracking
of the success of tuberculosis control programmes and identification of remaining challenges. We assessed trends in the fatal and non-fatal burden of tuberculosis over the past 25 years for 195 countries and territories.
Methods:
We analysed 10 691 site-years of vital registration data, 768 site-years of verbal autopsy data, and 361 site-years of mortality surveillance data using the Cause of Death Ensemble model to estimate tuberculosis mortality rates. We analysed all available age-specific and sex-specific data sources, including annual case notifications, prevalence surveys, and estimated cause-specific mortality, to generate internally consistent estimates of incidence, prevalence, and mortality using DisMod-MR 2.1, a Bayesian meta-regression tool. We assessed how observed tuberculosis incidence, prevalence, and mortality differed from expected trends as predicted by the Socio-demographic Index (SDI), a composite indicator based on income per capita, average years of schooling, and total fertility rate. We also estimated tuberculosis mortality and disability-adjusted life-years attributable to the independent effects of risk factors including smoking, alcohol use, and diabetes.
Findings:
Globally, in 2015, the number of tuberculosis incident cases (including new and relapse cases) was
10·2 million (95% uncertainty interval 9·2 million to 11·5 million), the number of prevalent cases was 10·1 million
(9·2 million to 11·1 million), and the number of deaths was 1·3 million (1·1 million to 1·6 million). Among individuals
who were HIV negative, the number of incident cases was 8·8 million (8·0 million to 9·9 million), the number of
prevalent cases was 8·9 million (8·1 million to 9·7 million), and the number of deaths was 1·1 million (0·9 million to 1·4 million). Annualised rates of change from 2005 to 2015 showed a faster decline in mortality (–4·1%
[–5·0 to –3·4]) than in incidence (–1·6% [–1·9 to –1·2]) and prevalence (–0·7% [–1·0 to –0·5]) among HIV-negative
individuals. The SDI was inversely associated with HIV-negative mortality rates but did not show a clear gradient for incidence and prevalence. Most of Asia, eastern Europe, and sub-Saharan Africa had higher rates of HIV-negative tuberculosis burden than expected given their SDI. Alcohol use accounted for 11·4% (9·3–13·0) of global tuberculosis deaths among HIV-negative individuals in 2015, diabetes accounted for 10·6% (6·8–14·8), and smoking accounted for 7·8% (3·8–12·0).
Interpretation:
Despite a concerted global effort to reduce the burden of tuberculosis, it still causes a large disease
burden globally. Strengthening of health systems for early detection of tuberculosis and improvement of the quality
of tuberculosis care, including prompt and accurate diagnosis, early initiation of treatment, and regular follow-up, are priorities. Countries with higher than expected tuberculosis rates for their level of sociodemographic development should investigate the reasons for lagging behind and take remedial action. Efforts to prevent smoking, alcohol use, and diabetes could also substantially reduce the burden of tuberculosis
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