1,652 research outputs found
Unveiling spatial patterns of population in Italian municipalities
We study the evolution of population density across Italian municipalities on
the based of their trajectories in the Moran space. We find evidence of spatial
dynamical patterns of concentrated urban growth, urban sprawl, agglomeration,
and depopulation. Over the long run, three distinct settlement systems emerge:
urban, suburban, and rural. We discuss how estimating these demographic trends
at the municipal level can help the design and validation of policies
contrasting the socio-economic decline in specific Italian areas, as in the
case of the Italian National Strategy for Inner Areas (Strategia Nazionale per
le Aree Interne, SNAI).Comment: 29 page
HGF modulates actin cytoskeleton remodeling and contraction in testicular myoid cells
The presence of the HGF/Met system in the testicular myoid cells was first discovered by our group. However, the physiological role of this pathway remains poorly understood. We previously reported that HGF increases uPA secretion and TGF-β activation in cultured tubular fragments and that HGF is maximally expressed at
Stages VII–VIII of the seminiferous epithelium cycle, when myoid cell contraction occurs. It is well known that the HGF/Met pathway is involved in cytoskeletal remodeling; moreover, the interaction of uPA with its receptor, uPAR, as well as the activation of
TGF-β have been reported to be related to the actin cytoskeleton contractility of smooth muscle cells. Herein, we report that HGF induces actin cytoskeleton remodeling in vitro in isolated myoid cells and myoid cell contraction in cultured seminiferous tubules. To better understand these phenomena, we evaluated: (1) the regulation of the uPA machinery in isolated myoid cells after HGF administration; and (2) the effect of uPA or Met inhibition on HGF-treated tubular fragments. Because uPA activates latent TGF-β, the secretion of this factor was also evaluated. We found that both uPA and TGF-β activation increase after HGF administration. In testicular tubular fragments, HGF-induced TGF-β activation and myoid cell contraction are abrogated by uPA or Met inhibitor administratio
R-spondin 1/Dickkopf-1/beta-catenin machinery is involved in testicular embryonic angiogenesis
Testicular vasculogenesis is one of the key processes regulating male gonad morphogenesis. The knowledge of the molecular cues underlining this phenomenon is one of today's most challenging issues and could represent a major contribution toward a better understanding of the onset of testicular morphogenetic disorders. R-spondin 1 has been clearly established as a candidate for mammalian ovary determination. Conversely, very little information is available on the expression and role of R-spondin 1 during testicular morphogenesis. This study aims to clarify the distribution pattern of R-spondin 1 and other partners of its machinery during the entire period of testicular morphogenesis and to indicate the role of this system in testicular development. Our whole mount immunofluorescence results clearly demonstrate that R-spondin 1 is always detectable in the testicular coelomic partition, where testicular vasculature is organized, while Dickkopf-1 is never detectable in this area. Moreover, organ culture experiments of embryonic male UGRs demonstrated that Dickkopf-1 acted as an inhibitor of testis vasculature formation. Consistent with this observation, real-time PCR analyses demonstrated that DKK1 is able to slightly but significantly decrease the expression level of the endothelial marker Pecam1. The latter experiments allowed us to observe that DKK1 administration also perturbs the expression level of the Pdgf-b chain, which is consistent with some authors' observations relating this factor with prenatal testicular patterning and angiogenesis. Interestingly, the DKK1 induced inhibition of testicular angiogenesis was rescued by the co-administration of R-spondin 1. In addition, R-spondin 1 alone was sufficient to enhance, in culture, testicular angiogenesis
Extending Virial Black Hole Mass Estimates to Low-Luminosity or Obscured AGN: the cases of NGC 4395 and MCG -01-24-012
In the last decade, using single epoch (SE) virial based spectroscopic
optical observations, it has been possible to measure the black hole (BH) mass
on large type 1 Active Galactic Nuclei (AGN) samples. However this kind of
measurements can not be applied on those obscured type 2 and/or low luminosity
AGN where the nuclear component does not dominate in the optical. We have
derived new SE relationships, based on the FWHM and luminosity of the broad
line region component of the Pabeta emission line and/or the hard X-ray
luminosity in the 14-195 keV band, which have the prospect of better working
with low luminosity or obscured AGN. The SE relationships have been calibrated
in the 10^5-10^9 M_sol mass range, using a sample of AGN whose BH masses have
been previously measured using reverberation mapping techniques. Our tightest
relationship between the reverberation-based BH mass and the SE virial product
has an intrinsic spread of 0.20 dex. Thanks to these SE relations, in agreement
with previous estimates, we have measured a BH mass of M_BH =1.7^+1.3_-0.7 X
10^5 M_sol for the low luminosity, type 1, AGN NGC 4395 (one of the smallest
active galactic BH known). We also measured, for the first time, a BH mass of
M_BH = 1.5^+1.1_-0.6 X 10^7 M_sol for the Seyfert 2 galaxy MCG -01-24-012.Comment: 10 pages, 7 figures. Accepted by MNRA
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Dissecting the sharp response of a canonical developmental enhancer reveals multiple sources of cooperativity.
Developmental enhancers integrate graded concentrations of transcription factors (TFs) to create sharp gene expression boundaries. Here we examine the hunchback P2 (HbP2) enhancer which drives a sharp expression pattern in the Drosophila blastoderm embryo in response to the transcriptional activator Bicoid (Bcd). We systematically interrogate cis and trans factors that influence the shape and position of expression driven by HbP2, and find that the prevailing model, based on pairwise cooperative binding of Bcd to HbP2 is not adequate. We demonstrate that other proteins, such as pioneer factors, Mediator and histone modifiers influence the shape and position of the HbP2 expression pattern. Comparing our results to theory reveals how higher-order cooperativity and energy expenditure impact boundary location and sharpness. Our results emphasize that the bacterial view of transcription regulation, where pairwise interactions between regulatory proteins dominate, must be reexamined in animals, where multiple molecular mechanisms collaborate to shape the gene regulatory function
Leveraging substrate flexibility and product selectivity of acetogens in two-stage systems for chemical production
Carbon dioxide (CO2 ) stands out as sustainable feedstock for developing a circular carbon economy whose energy supply could be obtained by boosting the production of clean hydrogen from renewable electricity. H2 -dependent CO2 gas fermentation using acetogenic microorganisms offers a viable solution of increasingly demonstrated value. While gas fermentation advances to achieve commercial process scalability, which is currently limited to a few products such as acetate and ethanol, it is worth taking the best of the current state-of-the-art technology by its integration within innovative bioconversion schemes. This review presents multiple scenarios where gas fermentation by acetogens integrate into double-stage biotechnological production processes that use CO2 as sole carbon feedstock and H2 as energy carrier for products' synthesis. In the integration schemes here reviewed, the first stage can be biotic or abiotic while the second stage is biotic. When the first stage is biotic, acetogens act as a biological platform to generate chemical intermediates such as acetate, formate and ethanol that become substrates for a second fermentation stage. This approach holds the potential to enhance process titre/rate/yield metrics and products' spectrum. Alternatively, when the first stage is abiotic, the integrated two-stage scheme foresees, in the first stage, the catalytic transformation of CO2 into C1 products that, in the second stage, can be metabolized by acetogens. This latter scheme leverages the metabolic flexibility of acetogens in efficient utilization of the products of CO2 abiotic hydrogenation, namely formate and methanol, to synthesize multicarbon compounds but also to act as flexible catalysts for hydrogen storage or production
Dose reduction and discontinuation of standard-dose regorafenib associated with adverse drug events in cancer patients: a systematic review and meta-analysis
Regorafenib (REG) is an oral multikinase inhibitor used in colorectal cancer,
gastrointestinal stromal tumour and hepatocellular carcinoma. Several adverse events
(AEs) are commonly reported during REG administration, and strategies for managing AEs in
everyday clinical practice include supportive care, dose modifications and, when necessary,
treatment withdrawal. We performed a systematic review and meta-analysis to assess the
schedule treatment modifications of REG associated with AEs across randomized controlled
clinical trials (RCTs
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