Abstract Randomized Controlled Trials (RCTs) are the “gold standard” for evaluating treatment outcomes providing information on treatments “efficacy”. They are designed to test a therapeutic ...hypothesis under optimal setting in the absence of confounding factors. For this reason they have high internal validity. The strict and controlled conditions in which they are conducted, leads to low generalizability because they are performed in conditions very different from real life usual care. Conversely, real life studies inform on the “effectiveness” of a treatment, that is, the measure of the extent to which an intervention does what is intended to do in routine circumstances. At variance to RCTs, real life trials have high generalizability, but low internal validity. Recently the number of real life studies has been rapidly growing in different areas of respiratory medicine, particularly in asthma and COPD. The role of such studies is becoming a hot topic in respiratory medicine, attracting research interest and debate. In the first part of this review we discuss some of the advantages and disadvantages of different types of RCTs and analyze the strengths and weaknesses of real life trials, considering the recent examples of some studies conducted in COPD. We then discuss methodological approaches and options to overcome some of the limitations of real life studies. Comparing the conclusions of effectiveness and efficacy trials can provide important pieces of information. Indeed, these approaches can result complementary, and they can guide the interpretation of each other results.
We report the case of a glomus tumor originating in the left main bronchus diagnosed in a 79 year old Caucasian man. A glomus tumor is an extremely rare neoplasm in the bronchi with nonspecific ...clinical features. Bronchoscopy allows the diagnosis through biopsy and subsequent histopathological examination of the tissue and in selected cases may represent a valid alternative to surgery permitting a radical tumor excision.
Respiratory viral infections are recognized as the most frequent cause of asthma and chronic obstructive pulmonary disease (COPD) exacerbations with rhinovirus (i.e. the virus of the common cold) ...being the most frequent identified virus. The recent development of human experimental models of rhinovirus-induced asthma and COPD exacerbations represent innovative tools with the potential to increase our understanding in this field. Moreover this models will provide the opportunity to test, in a carefully controlled setting, novel pharmacological compounds. In this review we will provide an overview of the role of viral infections in asthma and COPD exacerbations and in particular we will summarize the inflammatory and immunological mechanisms that can pave the way to exacerbation following respiratory viral infection in these patients.
We analyzed the near-infrared to UV data of 16 quasars with redshifts ranging from 0.71 <z< 2.13 to investigate dust extinction properties. The sample presented in this work was obtained from the ...High AV Quasar (HAQ) survey. The quasar candidates were selected from the Sloan Digital Sky Survey (SDSS) and the UKIRT Infrared Deep Sky Survey (UKIDSS), and follow-up spectroscopy was carried out at the Nordic Optical Telescope (NOT) and the New Technology Telescope (NTT). To study dust extinction curves intrinsic to the quasars, we selected 16 cases from the HAQ survey for which the Small Magellanic Cloud (SMC) law could not provide a good solution to the spectral energy distributions (SEDs). We derived the extinction curves using the Fitzpatrick & Massa (1986, ApJ, 307, 286, FM) law by comparing the observed SEDs to a combined previously published quasar template. The derived extinction, AV, ranges from 0.2–1.0 mag. All the individual extinction curves of our quasars are steeper (RV = 2.2–2.7) than that of the SMC, with a weighted mean value of RV = 2.4. We derived an average quasar extinction curve for our sample by simultaneously fitting SEDs by using the weighted mean values of the FM law parameters and a varying RV. The entire sample is well fit with a single best-fit value of RV = 2.2 ± 0.2. The average quasar extinction curve deviates from the steepest Milky Way and SMC extinction curves at a confidence level ≳95%. Such steep extinction curves suggest that a significant population of silicates is involved in producing small dust grains. Another possibility might be that the large dust grains may have been destroyed by the activity of the nearby active galactic nuclei (AGN), resulting in steep extinction curves.
The prevalence of Celiac Disease (CD), an autoimmune enteropathy, characterized by chronic inflammation of the intestinal mucosa, atrophy of intestinal villi and several clinical manifestations has ...increased in recent years. Subjects affected by CD cannot tolerate gluten protein, a mixture of storage proteins contained in several cereals (wheat, rye, barley and derivatives). Gluten free-diet remains the cornerstone treatment for celiac patients. Therefore the absence of gluten in natural and processed foods represents a key aspect of food safety of the gluten-free diet. A promising area is the use of minor or pseudo-cereals such as amaranth, buckwheat, quinoa, sorghum and teff. The paper is focused on the new definition of gluten-free products in food label, the nutritional properties of the gluten-free cereals and their use to prevent nutritional deficiencies of celiac subjects.
Context. Star-forming galaxies at high redshift show anomalous values of infrared excess, which can be described only by extremizing the existing relations between the shape of their ultraviolet ...continuum emission and their infrared-to-ultraviolet luminosity ratio, or by constructing ad hoc models of star formation and dust distribution. Aims. We present an alternative explanation, based on unveiled AGN activity, of the existence of such galaxies. The scenario of a weak AGN lends itself naturally to explain the observed spectral properties of these high-z objects in terms of a continuum slope distribution and not altered infrared excesses. Methods. To this end, we directly compare the infrared-to-ultraviolet properties of high-redshift galaxies to those of known categories of AGN (quasars and Seyferts). We also infer the characteristics of their possible X-ray emission. Results. We find a strong similarity between the spectral shapes and luminosity ratios of AGN with the corresponding properties of such galaxies. In addition, we derive expected X-ray fluxes that are compatible with the energetics from AGN activity. Conclusions. We conclude that a moderate AGN contribution to the UV emission of such high-z objects is a valid alternative to explain their spectral properties. Even the presence of an active nucleus in each source would not violate the expected quasar statistics. Furthermore, we suggest that the observed similarities between anomalous star-forming galaxies and quasars may provide a benchmark for future theoretical and observational studies on the galaxy population in the early Universe.
•22 bee species were found visiting coffee flowers.•Forest cover positively affected native bee community at the shrub scale.•The presence of bees resulted in an increase in coffee fruit set of ...28%.•Apis mellifera abundance positively affected fruit set across spatial scales.•Native bee community affected fruit set differently at different scales.
Although several studies have shown that the presence of bees results in increased crop yields, the mechanisms that determine pollination service across different spatial scales are still largely unknown. Here, we evaluated the influence of landscape structure over bee community composition and coffee (Coffea arabica) pollination. Our study was undertaken in one of the most important coffee-producing regions of Brazil, and comprised nine landscapes of sun coffee plantations surrounded by different amounts of Atlantic Forest remnants. Using floral exclusion experiments we evaluated fruit set in 15 coffee shrubs per landscape. We also sampled the bees visiting coffee flowers. Our analyses were made at two landscape scales, with 1 and 2km radii, and one shrub scale, with 300m radius around each coffee shrub. We collected 241 bee individuals and identified a total of 22 species. The honeybee Apis mellifera (Apini) was the most abundant flower visitor followed by Trigona spinipes (Meliponini). Native bee abundance, richness and diversity were positively affected by forest cover at the shrub scale. Honeybee abundance, on the other hand, was negatively affected by forest cover at the shrub scale. The presence of bees resulted in an increase in coffee fruit set of 28%. A. mellifera abundance positively affected fruit set across spatial scales, while the composition of the native bee community affected fruit set differently at the landscape scales than at the shrub scale. Our work shows that bee pollination services are affected by landscape structure at different spatial scales. These findings can be used in conservation and agricultural planning to maximize crop production while safeguarding biodiversity and the provision of pollination services.
Substantial evidence in the last few decades suggests that outflows from supermassive black holes (SMBH) may play a significant role in the evolution of galaxies. These outflows, powered by active ...galactic nuclei (AGN), are thought to be the fundamental mechanism by which the SMBH transfers a significant fraction of its accretion energy to the surrounding environment. Large-scale outflows known as warm absorbers (WA) and fast disk winds known as ultra-fast outflows (UFO) are commonly found in the spectra of many Seyfert galaxies and quasars, and a correlation has been suggested between them. Recent detections of low ionization and low column density outflows, but with a high velocity comparable to UFOs, challenge such initial possible correlations. Observations of UFOs in AGN indicate that their energetics may be enough to have an impact on the interstellar medium (ISM). However, observational evidence of the interaction between the inner high-ionization outflow and the ISM is still missing. We present here the spectral analysis of 12
XMM-Newton
/EPIC archival observations of the quasar PG 1114+445, aimed at studying the complex outflowing nature of its absorbers. Our analysis revealed the presence of three absorbing structures. We find a WA with velocity
v
∼ 530 km s
−1
, ionization log
ξ
/erg cm s
−1
∼ 0.35, and column density log
N
H
/cm
−2
∼ 22, and a UFO with
v
out
∼ 0.145
c
, log
ξ
/erg cm s
−1
∼ 4, and log
N
H
/cm
−2
∼ 23. We also find an additional absorber in the soft X-rays (
E
< 2 keV) with velocity comparable to that of the UFO (
v
out
∼ 0.120
c
), but ionization (log
ξ
/erg cm s
−1
∼ 0.5) and column density (log
N
H
/cm
−2
∼ 21.5) comparable with those of the WA. The ionization, velocity, and variability of the three absorbers indicate an origin in a multiphase and multiscale outflow, consistent with entrainment of the clumpy ISM by an inner UFO moving at ∼15% the speed of light, producing an entrained ultra-fast outflow (E-UFO).
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