Summary
Background
The frequency of eosinophilic oesophagitis (EoE) occurrence is escalating. Current diagnostic criteria recently proposed for the disease, determine that previous estimates of ...incidence and prevalence are outdated.
Aim
To gauge the current incidence and prevalence of EoE by performing a systematic review of population‐based studies.
Methods
Three electronic databases were searched from their inception dates to September 2018. A total of 2386 documents were screened; 29 studies reported on the prevalence and incidence of EoE in the general population.
Results
The pooled prevalence of EoE was 34.4 cases per 100 000 inhabitants (95% CI, 23.1‐47.5), and was higher for adults (42.2; 95% CI, 31.1‐55) than for children (34; 95% CI, 22.3‐49.2). The pooled EoE incidence rates were 6.6/100 000 person‐years (95% CI, 3‐11.7) in children and 7.7/100 000 (95% CI, 1.8‐17.8) in adults. No differences were found between North American and European studies using varied sources of data (insurance and administrative databases compared to hospital‐bases case series). Subgroup analysis according to risk of bias did not change results significantly. A steady rise in EoE incidence and prevalence rates was observed over time, comparing studies conducted under subsequent definitions for EoE. No significant publication bias was found.
Conclusions
In a systematic review and meta‐analysis, we found a sharp increase, higher than previous estimates, in the incidence and prevalence of EoE in population based studies. Results from studies carried out in developed countries show broad consistency and provide evidence of increasing pooled prevalence and incidence of EoE rates over time.
1. Dispersal is fundamental to ecological processes at all scales and levels of organization, but progress is limited by a lack of information about the general shape and form of plant dispersal ...kernels. We addressed this gap by synthesizing empirical data describing seed dispersal and fitting general dispersal kernels representing major plant types and dispersal modes. 2. A comprehensive literature search resulted in 107 papers describing 168 dispersal kernels for 144 vascular plant species. The data covered 63 families, all the continents except Antarctica, and the broad vegetation types of forest, grassland, shrubland and more open habitats (e.g. deserts). We classified kernels in terms of dispersal mode (ant, ballistic, rodent, vertebrates other than rodents, vehicle or wind), plant growth form (climber, graminoid, herb, shrub or tree), seed mass and plant height. 3. We fitted 11 widely used probability density functions to each of the 168 data sets to provide a statistical description of the dispersal kernel. The exponential power (ExP) and log-sech (LogS) functions performed best. Other 2-parameter functions varied in performance. For example, the log-normal and Weibull performed poorly, while the 2Dt and power law performed moderately well. Of the single-parameter functions, the Gaussian performed very poorly, while the exponential performed better. No function was among the best-fitting for all data sets. 4. For 10 plant growth form/dispersal mode combinations for which we had >3 data sets, we fitted ExP and LogS functions across multiple data sets to provide generalized dispersal kernels. We also fitted these functions to subdivisions of these growth form/dispersal mode combinations in terms of seed mass (for animal-dispersed seeds) or plant height (wind-dispersed) classes. These functions provided generally good fits to the grouped data sets, despite variation in empirical methods, local conditions, vegetation type and the exact dispersal process. 5. Synthesis. We synthesize the rich empirical information on seed dispersal distances to provide standardized dispersal kernels for 168 case studies and generalized kernels for plant growth form/dispersal mode combinations. Potential uses include the following: (i) choosing appropriate dispersal functions in mathematical models; (ii) selecting informative dispersal kernels for one's empirical study system; and (iii) using representative dispersal kernels in cross-taxon comparative studies.
Sarcomas are heterogeneous and clinically challenging soft tissue and bone cancers. Although constituting only 1% of all human malignancies, sarcomas represent the second most common type of solid ...tumors in children and adolescents and comprise an important group of secondary malignancies. More than 100 histological subtypes have been characterized to date, and many more are being discovered due to molecular profiling. Owing to their mostly aggressive biological behavior, relative rarity, and occurrence at virtually every anatomical site, many sarcoma subtypes are in particular difficult‐to‐treat categories. Current multimodal treatment concepts combine surgery, polychemotherapy (with/without local hyperthermia), irradiation, immunotherapy, and/or targeted therapeutics. Recent scientific advancements have enabled a more precise molecular characterization of sarcoma subtypes and revealed novel therapeutic targets and prognostic/predictive biomarkers. This review aims at providing a comprehensive overview of the latest advances in the molecular biology of sarcomas and their effects on clinical oncology; it is meant for a broad readership ranging from novices to experts in the field of sarcoma.
Sarcomas are heterogeneous and clinically challenging soft tissue and bone cancers. The current article comprehensively reviews recent advances in the molecular characterization of sarcoma subtypes, and describes novel therapeutic targets and biomarkers in this field.
The last 85,000 years were characterized by high climate and environmental variability on the Yucatán Peninsula. Heinrich stadials are examples of abrupt climate transitions that involved shifts in ...regional temperatures and moisture availability. Thus, they serve as natural experiments to evaluate the contrasting responses of aquatic and terrestrial ecosystems. We used ostracodes and pollen preserved in a 75.9-m-long sediment core (PI-6, ~85 ka) recovered from Lake Petén Itzá, Guatemala, to assess the magnitude and velocity of community responses. Ostracodes are sensitive to changes in water temperature and conductivity. Vegetation responds to shifts in temperature and the ratio of evaporation to precipitation. Ostracodes display larger and more rapid community changes than does vegetation. Heinrich Stadial 5-1 (HS5-1) was cold and dry and is associated with lower ostracode and vegetation species richness and diversity. In contrast, the slightly warmer and dry conditions during HS6 and HS5a are reflected in higher ostracode species richness and diversity. Our paleoecological study revealed the greatest ecological turnover for ostracodes occurred from 62.5 to 51.0 ka; for pollen, it was at the Pleistocene/Holocene transition. Future studies should use various climate and environmental indicators from lake and marine sediment records to further explore late glacial paleoclimate causes and effects in the northern neotropics.
Summary
The limitations of the well‐known LASSO regression as a variable selector are tested when there exists dependence structures among covariates. We analyse both the classic situation with n ≥ p ...and the high dimensional framework with p > n. Known restrictive properties of this methodology to guarantee optimality, as well as inconveniences in practice, are analysed and tested by means of an extensive simulation study. Examples of these drawbacks are showed making use of different dependence scenarios. In order to search for improvements, a broad comparison with LASSO derivatives and alternatives is carried out. Eventually, we give some guidance about what procedures work best in terms of the considered data nature.
The Great Lakes region of Central Africa is a major producer of common beans in Africa. The region is known for high population density and small average farm size. The common bean represents the ...most important legume crop of the region, grown on over a third of the cultivated land area, and the per capita consumption is among the highest in the world for the food crop. The objective of this study was to evaluate the genetic diversity in a collection of 365 genotypes from the Great Lakes region of Central Africa, including a large group of landraces from Rwanda as well as varieties from primary centers of diversity and from neighboring countries of Central Africa, such as the Democratic Republic of Congo and Uganda, using 30 fluorescently labeled microsatellite markers and automated allele detection. In addition, the landraces were evaluated for their seed iron and zinc concentration to determine if genetic diversity influenced nutritional quality. Principal coordinate and neighbor-joining analyses allowed the separation of the landraces into 132 Andean and 195 Mesoamerican (or Middle American) genotypes with 32 landraces and 6 varieties intermediate between the gene pools and representing inter-gene pool introgression in terms of seed characteristics and alleles. Genetic diversity and the number of alleles were high for the collection, reflecting the preference for a wide range of seed types in the region and no strong commercial class preference, although red, red mottled and brown seeded beans were common. Observed heterozygosity was also high and may be explained by the common practice of maintaining seed and plant mixtures, a coping strategy practiced by Central African farmers to reduce the effects of abiotic and biotic stresses. Finally, nutritional quality differed between the gene pools with respect to seed iron and zinc concentration, while genotypes from the intermediate group were notably high in both minerals. In conclusion, this study has shown that Central African varieties of common bean are a source of wide genetic diversity with variable nutritional quality that can be used in crop improvement programs for the region.
Summary
A new operon for biodesulfurization (BDS) of dibenzothiophene and derivatives has been isolated from a metagenomic library made from oil‐contaminated soil, by selecting growth of E. coli on ...DBT as the sulfur source. This operon is similar to a dszEABC operon also isolated by metagenomic functional screening but exhibited substantial differences: (i) the new fosmid provides much faster growth on DBT; (ii) associated dszEABC genes can be expressed without the need of heterologous expression from the vector promoter; and (iii) monooxygenases encoded in the fosmid cannot oxidize indole to produce indigo. We show how expression of the new dszEABC operon is regulated by the sulfur source, being induced under sulfur‐limiting conditions. Its transcription is activated by DszR, a type IV activator οf σN‐dependent promoters. DszR is coded in a dszHR operon, whose transcription is in turn regulated by sulfur and presumably activated by the global regulator of sulfur metabolism CysB. Expression of dszH is essential for production of active DszR, although it is not involved in sulfur sensing or regulation. Two broad‐host‐range DBT biodesulfurization catalysts have been constructed and shown to provide DBT biodesulfurization capability to three Pseudomonas strains, displaying desirable characteristics for biocatalysts to be used in BDS processes.
Intraaortic balloon pump counterpulsation is the most common form of mechanical circulatory support used in patients with myocardial ischemia and cardiogenic shock. The physiologic principles of ...counterpulsation include diastolic augmentation of aortic pressure and systolic reduction of left ventricular afterload, resulting in hemodynamic benefits through increased coronary perfusion pressure and improved myocardial oxygen balance in patients with myocardial ischemia. Major trials have failed to conclusively demonstrate improvements in morbidity and mortality with counterpulsation therapy for patients with acute myocardial infarction (MI), cardiogenic shock, and/or severe coronary artery disease undergoing revascularization therapy, and the debate over its applications continues. Part I of this review focuses on the history of the development of counterpulsation, technical considerations, and complications associated with its use, its physiologic effects, and evidence for its use in myocardial ischemia and cardiogenic shock.
Summary
Functional screening for aromatic ring oxygenases of an oil contaminated soil metagenome identified 25 different clones bearing monooxygenases coding genes. One fosmid bore an operon ...containing four tightly linked genes coding for a complete dibenzothiophene biodesulfurization pathway, which included the predicted monooxygenases DszC and DszA, the desulfinase DszB, and an FMN‐oxidoreductase designated DszE. The dszEABC operon provided Escherichia coli with the ability to use dibenzothiophene as the only sulfur source. Transcription of the operon is driven from a σN‐dependent promoter and regulated by an activator that was designated dszR. DszR has been purified and characterized in vitro and shown to be a constitutively active σN‐dependent activator of the group IV, which binds to two contiguous sequences located upstream of the promoter. The dsz promoter and dszE and dszR genes have apparently been recruited from an aliphatic sulfonate biodegradation pathway. If transcribed from a heterologous upstream promoter, the σN‐dependent promoter region functions as an ‘insulator’ that prevents translation of dszE, by binding with its ribosome binding site. Translational coupling, in turn, prevents translation of the downstream dszABC genes. The silencer combined with translational coupling thus represents an effective way of preventing expression of operons when spuriously transcribed from upstream promoters.
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