133 research outputs found
The presence and localization of apelin in the sheep abomasum: impact of diets characterized by different chemical composition
The apelinergic system is a complex system including the apelin peptide (AP), initially isolated in 1998 from bovine stomach homogenates and its receptor, named APJ receptor. The apelin peptide is extensively expressed in several human and laboratory animal organs (heart, lung, brain, mammary gland). Between the different roles hypothesize for apelin there are also the control of blood pressure and the stimulation of drinking behavior in rats. Recently its expression was also evidenced in the basal glandular portion of the stomach in laboratory animals, allowing to hypothesize its intervention in the control of acid secretion. No data concerning its presence and distribution in the abomasums of the sheep are present at the moment. So, we decided to test the presence and distribution of apelin in the abomasums of the sheep and the possible existence of a variability as a consequence of the different water content of the diet.The experiment was conducted using 50 sheep fed on Apennine semi-natural pasture for two experimental periods: in the first period the animals were fed for 45 days on the pasture at the maximum of its flowering; in the second one the animals were fed on the same pasture until its maximum dryness but the half of them daily received adiet integration of cereals. At the end of each experimental period, some animals were regularly slaughtered at the local abattoir, the abomasum specimens were immediately removed and some of them processed for routine tissue-embedding preparation while other for molecular biology.
The immunohistochemical reaction was visualized on 5 µm serial sections, using a primary rabbit polyclonal antibody (anti-AP), the avidin-biotin-complex and the DAB as the chromogen.
The immunohistochemical study showed a peculiar immunoreaction for AP in the abomasum of the animals examined. In particular, a immunopositive reaction for AP was evident in the cells of the basal third of the tubular glands and they were mainly of the closed type, with an oval or round shape and contained many perinuclear granules. The immunopositive reactions didn’t evidence any difference both in the localization and in the number of the positive cells, between the different groups. Immuno-positivity for AP was not observed in any other histological structure or in the sections utilized as negative controls.These results allow us to conclude that AP is present in the glandular tissue of the abomasums of the sheep, as observed in laboratory animals, with a peculiar cytoplasmatic localization and to hypothesize that AP is involved in the control of gastric secretion, probably via APJ receptor. The AP expression in the stomach doesn’t seem to be influenced by the water content of the diets with a positivity that appears to be localized in the same glandular portion between the different animal groups
Linear regression for numeric symbolic variables: an ordinary least squares approach based on Wasserstein Distance
In this paper we present a linear regression model for modal symbolic data.
The observed variables are histogram variables according to the definition
given in the framework of Symbolic Data Analysis and the parameters of the
model are estimated using the classic Least Squares method. An appropriate
metric is introduced in order to measure the error between the observed and the
predicted distributions. In particular, the Wasserstein distance is proposed.
Some properties of such metric are exploited to predict the response variable
as direct linear combination of other independent histogram variables. Measures
of goodness of fit are discussed. An application on real data corroborates the
proposed method
Weight loss and clinical characteristics of young adults patients seeking treatment at medical centers: Data from the QUOVADIS Study
OBJECTIVE: To compare clinical characteristics, attrition, weight loss, and psychological
changes of obese young adults and obese adults seeking treatment. MATERIALS
AND METHODS: 1530 individuals seeking treatment in 18 Italian medical centers were evaluated.
382 cases (25%) were classified as young adults (age≤35 years), 1148 (75%) as adults (>35
years). Psychological distress, binge eating, body uneasiness, and attitude towards eating were
evaluated, at baseline and after a 12-month weight-loss program, together with BMI
changes. Weight-loss expectations and primary motivation for seeking treatment were also
recorded. RESULTS: At baseline, young adults reported significantly higher BMI at age 20,
weight loss expectations and body uneasiness scores than adults. A significantly higher percentage
of young adults also reported improving appearance as primary reason for seeking
treatment. The attrition rate was significantly larger in young adults. Among completers, the
mean percent weight loss at 12 months and improvement of psychosocial variables were significantly
higher in young adults than in adults. By intention to treat, BMI changes were no
longer significant between groups. DISCUSSION: Obese young adults lose more weight
and considerably improve psychological distress, but show a higher attrition rate after 12
months of continuous care in a real world medical setting
Measurements of the UV background at 4.6 < z < 6.4 using the quasar proximity effect
We present measurements of the ionising ultraviolet background (UVB) at z ~
5-6 using the quasar proximity effect. The fifteen quasars in our sample cover
the range 4.6 < z_q < 6.4, enabling the first proximity effect measurements of
the UVB at z > 5. The metagalactic hydrogen ionisation rate, Gamma_bkg, was
determined by modelling the combined ionisation field from the quasar and the
UVB in the proximity zone on a pixel-by-pixel basis. The optical depths in the
spectra were corrected for the expected effect of the quasar until the mean
flux in the proximity region equalled that in the average Ly-alpha forest, and
from this we make a measurement of Gamma_bkg. A number of systematic effects
were tested using synthetic spectra. Noise in the flux was found to be the
largest source of bias at z ~ 5, while uncertainties in the mean transmitted
Ly-alpha flux are responsible for the largest bias at z ~ 6. The impacts of
large-scale overdensities and Lyman limit systems on Gamma_bkg were also
investigated, but found to be small at z > 5. We find a decline in Gamma_bkg
with redshift, from log(Gamma_bkg) = -12.15 0.16 at z ~ 5 to
log(Gamma_bkg) = -12.84 0.18 at z ~ 6 (1 sigma errors). Compared to UVB
measurements at lower redshifts, our measurements suggest a drop of a factor of
five in the HI photoionisation rate between z ~ 4 and z ~ 6. The decline of
Gamma_bkg appears to be gradual, and we find no evidence for a sudden change in
the UVB at any redshift that would indicate a rapid change in the attenuation
length of ionising photons. Combined with recent measurements of the evolution
of the mean free path of ionising photons, our results imply decline in the
emissivity of ionising photons by roughly a factor of two from z ~ 5 to 6,
albeit with significant uncertainty due to the measurement errors in both
Gamma_bkg and the mean free path.Comment: 22 pages, 19 figures, 5 tables; accepted for publication in MNRA
The Interplay between Magnesium and Testosterone in Modulating Physical Function in Men
The role of nutritional status as determinant of successful aging is very well recognized. There is recent evidence that nutrition may exert its beneficial effects through the modulation of the hormonal anabolic milieu. Under-nutrition and anabolic hormonal deficiency frequently coexist in older individuals determining an increased risk of mobility impairment and adverse outcomes. Mineral dietary assessment has received attention as key component of the nutritional modulation of anabolic status and physical performance. There is evidence that several minerals, including magnesium, exert a positive influence on Insulin-like Growth Factor-1 (IGF-1) secretion in both sexes, and Testosterone (T) in men. In this review we summarize the existing knowledge about the mechanisms by which magnesium can affect T bioactivity in older men. Particular attention will be also devoted to the preliminary observational and intervention studies addressing the relationship between magnesium and T in adult and older individuals. We believe that, if larger studies will confirm these pivotal data, hormonal and mineral strategies might be adopted as synergistic treatment to approach the multifactorial nature of accelerated aging
The Circumgalactic Medium in Massive Halos
This chapter presents a review of the current state of knowledge on the cool
(T ~ 1e4 K) halo gas content around massive galaxies at z ~ 0.2-2. Over the
last decade, significant progress has been made in characterizing the cool
circumgalactic gas in massive halos of Mh ~ 1e12-1e14 Msun at intermediate
redshifts using absorption spectroscopy. Systematic studies of halo gas around
massive galaxies beyond the nearby universe are made possible by large
spectroscopic samples of galaxies and quasars in public archives. In addition
to accurate and precise constraints for the incidence of cool gas in massive
halos, detailed characterizations of gas kinematics and chemical compositions
around massive quiescent galaxies at z ~ 0.5 have also been obtained. Combining
all available measurements shows that infalling clouds from external sources
are likely the primary source of cool gas detected at d >~ 100 kpc from massive
quiescent galaxies. The origin of the gas closer in is currently less certain,
but SNe Ia driven winds appear to contribute significantly to cool gas found at
d < 100 kpc. In contrast, cool gas observed at d <~ 200 kpc from luminous
quasars appears to be intimately connected to quasar activities on parsec
scales. The observed strong correlation between cool gas covering fraction in
quasar host halos and quasar bolometric luminosity remains a puzzle. Combining
absorption-line studies with spatially-resolved emission measurements of both
gas and galaxies is the necessary next step to address remaining questions.Comment: 29 pages, 7 figures, invited review to appear in "Gas Accretion onto
Galaxies", Astrophysics and Space Science Library, eds. A. Fox & R. Dave, to
be published by Springe
Perfluoroalkyl substances, sex hormones, and insulin-like growth factor-1 at 6–9 Years of age : a cross-sectional analysis within the C8 health project
Background: Exposure to some perfluoroalkyl substances (PFAS), such as perfluorohexane sulfonate
(PFHxS), perfluorooctanoate (PFOA), perfluorooctane sulfonate (PFOS), and perfluorononanoic acid
(PFNA), may alter levels of sex hormones and insulin-like growth factor-1 (IGF-1) in animals. Human
studies on this topic are scarce and none have been conducted in young children.
Objectives: To investigate the relationship between levels of PFAS and estradiol, total testosterone and
IGF-1 in 2,292 children (aged 6-9 years) from the C8 Health Project living near a chemical plant in the
Mid-Ohio Valley (USA) with local contamination from PFOA.
Methods: Serum samples were collected in 2005-2006 and analyzed for PFAS, sex hormones and
IGF-1. Results from regression models were expressed as the adjusted percentage difference (95% CI)
per sex-specific interquartile range (IQR) increment of each PFAS serum concentration. Analyses by
PFAS quartiles were also conducted.
Results: Median concentrations of PFHxS, PFOA, PFOS, and PFNA were 8, 35, 22, and 1.7 ng/mL in
boys and 7, 30, 21, and 1.7 ng/mL in girls. In boys, PFOA concentrations were significantly associated
with testosterone levels (-4.9% [-8.7, -0.8%]); PFOS with estradiol (-4.0% [-7.7, -0.1%]), testosterone
(-5.8% [-9.4, -2.0%]), and IGF-1 (-5.9% [-8.3, -3.3%]); and PFNA with IGF-1 (-3.5% [-6.0, -1.0%]). In
girls, significant associations were found between PFOS and testosterone (-6.6% [-10.1, -2.8%]) and
IGF-1 (-5.6% [-8.2, -2.9%]); and PFNA and IGF-1 (-3.8% [-6.4, -1.2%]). In both sexes, the magnitudes
of the associations decreased monotonically across quartiles for testosterone and PFOS, and for IGF-1
and both PFOS and PFNA.
Conclusions: To our knowledge, this is the first study suggesting that PFAS are associated with lowe
XQ-100: A legacy survey of one hundred 3.5 72 z 72 4.5 quasars observed with VLT/X-shooter
We describe the execution and data reduction of the European Southern Observatory Large Programme "Quasars and their absorption lines: a legacy survey of the high-redshift Universe with VLT/X-shooter" (hereafter "XQ-100"). XQ-100 has produced and made publicly available a homogeneous and high-quality sample of echelle spectra of 100 quasars (QSOs) at redshifts z 43 3.5-4.5 observed with full spectral coverage from 315 to 2500 nm at a resolving power ranging from R \u303. 4000 to 7000, depending on wavelength. The median signal-to-noise ratios are 33, 25 and 43, as measured at rest-frame wavelengths 1700, 3000 and 3600 \uc5, respectively. This paper provides future users of XQ-100 data with the basic statistics of the survey, along with details of target selection, data acquisition and data reduction. The paper accompanies the public release of all data products, including 100 reduced spectra. XQ-100 is the largest spectroscopic survey to date of high-redshift QSOs with simultaneous rest-frame UV/optical coverage, and as such enables a wide range of extragalactic research, from cosmology and galaxy evolution to AGN astrophysics. \ua9 2016 ESO
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