208 research outputs found
The Truth of the Law. Reflections in the Margin of a Friedrich Dürrenmatt’s Short Story
The following reflections are inspired by a short story by Friedrich Dürrenmatt (1921-1990), who is unanimously considered, together with Brecht, as the greatest dramatist in Germany of the second post-war period. There is, however, an important difference that sets him apart from Brecht and this is despite the fact that Dürrenmatt did study and, in fact, ended up sharing many of Brecht's theories on epic theatre. This difference stems from the unforeseeability and unconventionality of Dürrenmatt's work that contributed, on a par with one of his countrymen, Max Frisch, to a radical renewal of dramaturgy written in Germany and which offered, in a somewhat grotesque way, a disturbing picture of the shabbiness hiding behind the appearance of respectability of the society in which he lived
Rischi pandemici
The author intends to use Niklas Luhmann’s social systems theory, and namely his sociology of risk, to assess the effects of the pandemic on crucial social communication systems, such as politics, mass media, economics, science, law, and love. Moving from the primary distinction between dangers and risks, the paper describes the transformation of pandemic dangers into risky decisions within each social communication system
A case of cilioretinal artery with hemiretinal distribution
The retinal vasculature is usually supplied by the central retinal artery (CRA), This is the first branch of ophthalmic artery in 77.5% (1). Cilioretinal arteries are reported to be present in up to 50% of eyes, and are considered to be the most common retinal vascular anomaly. Cilioretinal arteries take rise from a posterior ciliary artey (2). They may vary in size, number, distribution and point of origin from the optic disc. In most of the cases they are small arterioles supplying a part of central retina from the fovea to the optic disc. Only in 0.6%, large cilioretinal arteries can supply more than a quarter of the retinal circulation (3). We present a rare case of an individual with asymmetrical cilioretinal artery that arise inferiorly and supply the entire inferior emiretina. D.N., 7 years old male, affected by hyperopic astigmatism in both eyes. Clinical exam revealed no diseases. Examination of the fundus oculi showed, in the right eye, the presence of a very common small cilioretinal artery running from the disc to the foveal avascular zone. In the left eye, the central retinal artery gave rise only to two superior branches; a large cilioretinal artery entered the disc area from its inferotemporal edge, and gave rise to two inferior arterial branches. Thus, in the left eye, the CRA feeds the superior half of the retina; the large cilioretinal artery supplies the inferior half of the retina. Retinography was performed using a Confocal Color Scanning Ohthalmoscope (Eidon). This type of uncommon variant of retinal vasculature prevents extended retinal ischemia due to CRA occlusion
Retinal microvasculature. A comparison between experimental SEM corrosion casts observations and human in vivo “Angio-OCT” observations
In our previous studies on vascular corrosion casts of monkey posterior retina we were able to demonstrate the following points: 1) Capillaries have a laminar distribution. Most vitreal ones are favoured as they are more directly vascularized by side branching arterioles; 2) around the foveal avascular zone, capillaries show a round course and likely function as arteriovenous anastomoses; 3) different layers of capil- laries are connected by side branches of capillaries; 4) peculiar cast imprints at precapillary and capillary branching points are related to smooth muscle cells and pericytes that may perform fine blood flow regulation. Split-spectrum amplitude-decorrelation angiography (SSADA) is an Angio-OCT that provides imaging of the retinal vasculature without the need for intravenous injection of a fluorophore. SSADA makes it possible to follow single blood vessels in different focal planes and indirectly provides data on variation of vessel volume related to blood flow. We compared observation from our previous studies on corrosion casts in Cynomolgus monkeys with images of retinal vasculature as obtained in vivo in man by SSADA. An extremely close relation between monkey and man retinal microvascular anatomy was demonstrated. Both number of layers of capillaries and their connections closely corresponded. Further observations in different conditions may provide definitive information about blood flow regulation sites
The Hepatic Microcirculation in Experimental Cirrhosis a Scanning Electron Microscopy Study of Microcorrosion Casts
The experimental model of liver cirrhosis induced by intragastric administration of CCl4 reproduces not only the histological picture of the postnecrotic cirrhosis but also its pathophysiological features.
Corrosion casts of livers affected by CCl4-induced cirrhosis show the loss of the lobular pattern. Once the cirrhosis has completely developed, the whole microvascular bed appears to be composed of groups of sinusoid nodules of diameters varying between 0.3 and 1.5 mm.. Pre- and post-sinusoidal vessels and anastomoses between the former and the latter are mainly located at the perinodular spaces.
This microvascular situation modifies the normal perfusion gradient within the parenchyma. Nevertheless, it can allow a still viable function
Vasopressin regulates the growth of the biliary epithelium in polycystic liver disease
The neurohypophysial hormone arginine vasopressin (AVP) acts by three distinct receptor subtypes: V1a, V1b, and V2. In the liver, AVP is involved in ureogenesis, glycogenolysis, neoglucogenesis and regeneration. No data exist about the presence of AVP in the biliary epithelium. Cholangiocytes are the target cells in a number of animal models of cholestasis, including bile duct ligation (BDL), and in several human pathologies, such as polycystic liver disease characterized by the presence of cysts that bud from the biliary epithelium. In vivo, liver fragments from normal and BDL mice and rats as well as liver samples from normal and ADPKD patients were collected to evaluate: (i) intrahepatic bile duct mass by immunohistochemistry for cytokeratin-19; and (ii) expression of V1a, V1b and V2 by immunohistochemistry, immunofluorescence and real-time PCR. In vitro, small and large mouse cholangiocytes, H69 (non-malignant human cholangiocytes) and LCDE (human cholangiocytes from the cystic epithelium) were stimulated with vasopressin in the absence/presence of AVP antagonists such as OPC-31260 and Tolvaptan, before assessing cellular growth by MTT assay and cAMP levels. Cholangiocytes express V2 receptor that was upregulated following BDL and in ADPKD liver samples. Administration of AVP increased proliferation and cAMP levels of small cholangiocytes and LCDE cells. We found no effect in the proliferation of large mouse cholangiocytes and H69 cells. Increases were blocked by preincubation with the AVP antagonists. These results showed that AVP and its receptors may be important in the modulation of the proliferation rate of the biliary epithelium
La inclusión diferencial de los solicitantes de asilo en Italia.
This article aims to critically analyze the reception system for asylum seekers in Italy as a device for “differential inclusion” of migrants on the southern edge of Europe. To defend this argument, first, we will analyze the evolution and the main characteristics of this system, as well as its most recent transformations from 2011. Secondly, we will observe that the three main segments of the reception system can be found on a scale that goes from the greatest exclusion to the greatest inclusion. In third and last place, we will observe that the reception “best practices” also present an ambivalent character, producing a continuous tension between the two poles of reception and integration.Este trabajo pretende analizar críticamente el sistema de acogida de los solicitantes de asilo en Italia como dispositivo de “inclusión diferencial” de los migrantes en los confines meridionales de Europa. Para defender este argumento, en primer lugar, analizaremos la evolución y las principales características de ese sistema, además de sus transformaciones más recientes a partir del 2011. En segundo lugar, observaremos que los tres segmentos principales del sistema de acogida pueden hallarse en una escala que va desde la mayor exclusión a la mayor inclusión. En tercer y último lugar, observaremos que también las “mejores prácticas” de acogida presentan un carácter ambivalente que produce una continua tensión entre los dos polos de la acogida y de la integración
Joint analysis of gravitational-wave and electromagnetic data of mergers:breaking an afterglow model degeneracy in GW170817 and in future events
On August 17, 2017, Advanced LIGO and Virgo observed GW170817, the first
gravitational-wave (GW) signal from a binary neutron star merger. It was
followed by a short-duration gamma-ray burst, GRB 170817A, and by a non-thermal
afterglow emission. In this work, a combined simultaneous fit of the
electromagnetic (EM, specifically, afterglow) and GW domains is implemented,
both using the posterior distribution of a GW standalone analysis as prior
distribution to separately process the EM data, and fitting the EM and GW
domains simultaneously. These approaches coincide mathematically, as long as
the actual posterior of the GW analysis, and not an approximation, is used as
prior for the EM analysis. We treat the viewing angle, , as shared
parameter across the two domains. In the afterglow modelling with a Gaussian
structured jet this parameter and the jet core angle, , are
correlated, leading to high uncertainties on their values. The joint EM+GW
analysis relaxes this degeneracy, reducing the uncertainty compared to an
EM-only fit. We also apply our methodology to hypothetical GW170817-like events
occurring in the next GW observing run at 140 and 70 Mpc. At 70 Mpc the
existing EM degeneracy is broken, thanks to the inclusion of the GW domain in
the analysis. At 140 Mpc, the EM-only fit cannot constrain nor
because of the lack of detections in the afterglow rising phase.
Folding the GW data into the analysis leads to tighter constraints on
, still leaving unconstrained, requiring instruments with
higher sensitivities, such as Athena.Comment: 15 pages, 10 figures. Accepted for publication in MNRA
Vasopressin induces cholangiocyte proliferation in experimental cholestasis and in Polycystic Liver Disease
The hormone vasopressin (hereafter AVP) is a neuropeptide mainly synthesized in the brain’s hypothalamic paraventricular (PVN) and supraoptic (SON) nuclei, works by three distinct receptor subtypes: V1a, V1b, and V2 [1]. In liver, AVP is involved in glycogenolysis and neoglucogenesis and regenerative processes [2]. Cholangiocytes are the cells that line the biliary ducts and they are the target in a number of animal models of cholestasis including bile duct ligation (BDL) and in several human pathologies such as polycystic liver disease (PLD) characterized by the presence of numerous cysts within the liver that arise from biliary epithelium [3]. Since no data exist about the presence and the role of AVP and receptors in biliary epithelium, we aimed to evaluate the effects of AVP in experimental model of cholestasis and in course of PLD. In vivo, normal and BDL liver fragments from rats, normal and PLD from human patients were collected to evaluate: (i) intrahepatic bile duct mass (IBDM) by immunohistochemistry for citokeratin-19 (CK-19); and (ii) expression of V1a, V1b and V2 by immunohistochemistry, immunofluorescence and real time PCR. In vitro, small and large mouse cholangiocytes, H69 (non-malignant human cholangiocytes) and LCDE (human cholangiocytes from cystic epithelium) were stimulated with AVP in the absence/presence of antagonists such as OPC-31260 and Tolvaptan, before assessing cellular growth by MTT proliferation assay, cAMP levels by a RIA kit and the expression of some angiogenic factors, such as platelet-derived growth factor (PDGF) and Angiopoietins (Ang-1 and Ang-2). Cholangiocytes express V2 receptor that was upregulated following BDL and in course of polycystic disease. Treatment with AVP of cholangiocyte cultures increased proliferation, cAMP levels and expression of PDGF, Ang-1, Ang-2 in small cholangiocytes and LCDE cells. These increments were blocked by pre-incubation with the AVP antagonists. Our results showed that AVP play an important role in growth of the biliary epithelium during cholestasis and in cystic epithelium in course of PLD acting on the cAMP signalling pathway and increasing angiogenic factors. Additional studies are necessary, but these first results may be considered important in the regulation of the biliary growth/loss in course of cholangiopathies
Epidermal growth factor-like domain multiple 7 (EGFL7): Expression and possible effect on biliary epithelium growth in cholangiocarcinoma
Cholangiocarcinoma (CCA) is an aggressive biliary tract malignancy with limited treatment options and low survival rates. The intrahepatic subtype comprises two forms: mucin-iCCA and mixed-iCCA. Epidermal growth factor-like domain multiple (EGFL7) is overexpressed in less differentiated liver tumors. The aim of this study was to assess the presence of EGFL7 due to its possible role in the growth of CCA. Hematoxylin and Eosin and periodic acid-Schiff staining were used to evaluate the morphological aspects and glycogen deposition. Immunohistochemistry and immunofluorescence were performed to identify the presence of EGFL7 both in tumor sections ex vivo and in appropriate cell lines in culture. We found that EGFL7 is expressed in malignant cholangiocytes of mixed-iCCA and absent in mucin-iCCA. In conclusion the expression of EGFL7 might be useful in the classification of CCA subtypes
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