Both human and non-human animals frequently deal with risky decisions in a social environment. Nevertheless, the influence of the social context on decision-making has been scarcely investigated. ...Here, we evaluated for the first time whether the presence of a conspecific influences risk preferences in rats and in tufted capuchin monkeys. Subjects received a series of choices between a constant, safe option and a variable, risky option, both alone (Alone condition) and when paired with a conspecific (Paired condition). The average payoff of the risky option was always lower than that of the safe option. Overall, the two species differed in their attitude towards risk: whereas rats were indifferent between options, capuchins exhibited a preference for the safe option. In both species, risk preferences changed in the Paired condition compared to the Alone condition, although in an opposite way. Whereas rats increased their risk preferences over time when paired with a conspecific, capuchins chose the risky option less in the Paired condition than in the Alone condition. Moreover, whereas anxiety-like behaviours decreased across sessions in rats, these behaviours where more represented in the Paired condition than in the Alone condition in capuchins. Thus, our findings extends to two distantly-related non-human species the evidence, so far available for human beings, that a decrease in anxiety corresponds to an increase in risk preferences, and vice versa. This suggests that the modulation of risk preferences by social influences observed in rats and capuchin monkeys may rely on a common, evolutionarily ancient, mechanism.
This paper presents a data sink node election algorithm for multi-hop Wireless Sensor Networks (WSNs) with multiple data sink nodes. For energy-saving considerations, these nodes should be evenly ...(spatially) distributed on the network area. To achieve this objective, it proposed a distributed and iterative algorithm, which periodically re-assigns the data sink roles to selected WSN nodes. The main innovation of the algorithm is that, even if it does not need to explicitly compute the Voronoi partition of the WSN at each iteration, it eventually partitions the network according to a Centroidal Voronoid Tessellation, which leads to a spatially well-balanced distribution of the data sink nodes. Analytical proofs as well as simulation results validate the approach.
Aims/hypothesis Podocyte loss by apoptosis, in addition to favouring progression of established diabetic nephropathy, has been recently indicated as an early phenomenon triggering the initiation of ...glomerular lesions. This study aimed to assess the rate of glomerular cell death and its relationship with renal functional, structural and molecular changes in rats with experimental diabetes. Methods Male Sprague-Dawley rats with streptozotocin-induced diabetes and coeval non-diabetic control animals were killed at 7 days and at 2, 4 and 6 months for the assessment of apoptosis, renal function, renal structure and the expression of podocyte markers and apoptosis- and cell cycle-related proteins. Results Glomerular cell apoptosis was significantly increased in diabetic vs non-diabetic rats at 4 months and to an even greater extent at 6 months, with podocytes accounting for 70% of apoptosing cells. The increase in apoptosis was preceded by increases in proteinuria, albuminuria and mean glomerular and mesangial areas, and by reductions in glomerular cell density and content of synaptopodin and Wilms' tumour protein-1. It coincided with the development of mesangial expansion and glomerular sclerosis, and with the upregulation/activation both of tumour protein p53, which increased progressively throughout the study, and of p21 (also known as cyclin-dependent kinase inhibitor 1A, CIP1 and WAF1), which peaked at 4 months and decreased thereafter. Conclusions/interpretation Glomerular cell (podocyte) apoptosis is not an early feature in the course of experimental diabetic glomerulopathy, since it is preceded by glomerular hypertrophy, which may decrease glomerular cell density to the point of inducing compensatory podocyte hypertrophy. This is associated with reduced podocyte protein expression (podocytopathy) and proteinuria, and ultimately results in apoptotic cell loss (podocytopenia), driving progression to mesangial expansion and glomerular sclerosis.
Aims/hypothesis AGEs have been implicated in renal disease associated with ageing, diabetes and other age-related disorders. Reactive oxygen species (ROS) promote formation of AGEs, which cause ...AGE-receptor-mediated ROS generation with activation of signalling pathways leading to tissue injury and further AGE accumulation. ROS generation is regulated by the Src homology 2 domain-containing transforming protein C1 (Shc1) isoform p66Shc, whose deletion has been shown to protect from tissue injury induced by ageing, diabetes, hyperlipidaemia and ischaemia-reperfusion by preventing oxidative stress. This study was aimed at assessing the role of p66Shc in the modulation of oxidative stress and oxidant-dependent renal injury induced by AGEs. Methods For 10 weeks, male p66 shc knockout (KO) and wild-type (WT) mice were injected with 60 μg/day albumin modified or unmodified by graphic removed (CML). Mice were then killed for the assessment of renal function and structure, as well as systemic and renal tissue oxidative stress. Results Upon CML injection, KO mice, in contrast to WT mice, showed no or only mild forms of proteinuria, glomerular hypertrophy, mesangial expansion, glomerular sclerosis, renal/glomerular cell apoptosis and extracellular matrix upregulation. Moreover, KO mice had lower circulating and tissue AGEs than WT mice and unchanged plasma isoprostane 8-epi-prostaglandin- graphic removed levels, renal/glomerular CML, 4-hydroxy-2-nonenal, AGE receptor and NAD(P)H oxidase 4 (NOX4) content (and expression of the corresponding genes), and nuclear factor κB activation (NFκB). Mesangial cells from KO mice exposed to CML showed no or slight increase in ROS levels and NFκB activation, again at variance with WT cells. Conclusions/interpretation These data indicate that p66Shc participates in the pathogenesis of AGE-dependent glomerulopathy by mediating AGE-induced tissue injury and further AGE formation through ROS-dependent mechanisms involving NFκB activation and upregulation of Nox4 expression and NOX4 production.
ABSTRACT
We previously showed that mice lacking galectin‐3/AGE‐receptor 3 develop accelerated diabetic glomerulopathy. To further investigate the role of galectin‐3/AGE‐receptor function in the ...pathogenesis of diabetic renal disease, galectin‐3 knockout (KO) and coeval wild‐type (WT) mice were injected for 3 months with 30 μg/day of Nε‐carboxymethyllysine (CML)‐modified or unmodified mouse serum albumin (MSA). Despite receiving equal doses of CML, KO had higher circulating and renal AGE levels and showed more marked renal functional and structural changes than WT mice, with significantly higher proteinuria, albuminuria, glomerular, and mesangial area and glomerular sclerosis index. Renal 4‐hydroxy‐2‐nonenal content and NFκB activation were also more pronounced in KO‐CML vs. WT‐CML. Kidney mRNA levels of fibronectin, laminin, collagen IV, and TGF‐β were up‐regulated, whereas those of matrix metalloproteinase‐2 and ‐14 were down‐regulated, again more markedly in KO‐CML than WT‐CML mice. Basal and CML‐induced RAGE and 80K‐H mRNA levels were higher in KO vs. WT mice. MSA injection did not produce any significant effect in both genotypes. The association of galectin‐3 ablation with enhanced susceptibility to AGE‐induced renal disease, increased AGE levels and signaling, and altered AGE‐receptor pattern indicates that galectin‐3 is operating in vivo as an AGE receptor to afford protection toward AGE‐dependent tissue injury.
Wireless ad-hoc networks are collections of devices which are able to communicate each other through wireless links. Those networks differ from infrastructure-based wireless networks for the absence ...of a centralized coordinator which handles all the communications among the devices. This leads to higher probability of packets collision, congestion of links, etc. Moreover, wireless links are characterized by an intrinsic high and time varying packet loss ratio, due to external noise and interferences. The objective of this paper is to present a new distributed multi-path algorithm (i.e., traffic is split among multiple paths) for wireless ad-hoc networks with the aims of (i) increasing the throughput of the applications running onto the network (ii) explicitly accounting for the packet loss of the wireless links and (iii) guaranteeing that the routing process converges to stable paths. The algorithm is developed by using the concept of Wardrop equilibrium. Simulation results show the higher throughput achieved by the proposed routing algorithm, compared to shortest path routing protocols, based on hop count and on packet loss metrics.
Development of diabetic nephropathy in the Milan Normotensive Strain, but not in the Milan Hypertensive Strain: Possible permissive role of hemodynamics.
Rats of the Milan normotensive strain develop ...spontaneous glomerulosclerosis, whereas those of the Milan hypertensive strain are resistant to renal disease, possibly due to intrarenal artery hypertrophy protecting from systemic hypertension. To assess the role of hemodynamic versus metabolic factors in diabetic nephropathy, we investigated whether streptozotocin-induced diabetes accelerates glomerulosclerosis in Milan normotensive and/or removes (the hemodynamic) protection in Milan hypertensive rats by reducing preglomerular vascular resistance.
Diabetic and nondiabetic Milan normotensive, hypertensive, and progenitor Wistar rats were followed for 6 months for the assessment of renal function and structure.
Proteinuria increased in nondiabetic and diabetic normotensive and, to a lesser extent, in diabetic Wistar, but not hypertensive rats. Serum creatinine increased and creatinine clearance decreased in nondiabetic and diabetic normotensive rats at 6 months. At 1.5 months, diabetic normotensive, but not hypertensive rats showed increased glomerular filtration rate and filtration fraction, suggesting glomerular hypertension. Diabetic nephropathy was detected in diabetic normotensive and Wistar, but not hypertensive rats. Glomerular extracellular matrix and TGF-β mRNA levels increased with diabetes (and age) in normotensive, but not hypertensive rats. Arterioles and interlobular arteries showed increased media thickness in hypertensive versus normotensive rats, with diabetes reducing it only in the normotensive.
These data show that Milan hypertensive rats are not susceptible to diabetic nephropathy, at variance with glomerulosclerosis-prone Milan normotensive rats, thus indicating the importance of genetic background. Our study suggests that the nature of this (genetic) protection might be hemodynamic, with intrarenal artery hypertrophy preventing diabetes-induced loss of autoregulation.
The authors report a case of spinal subarachnoid hemorrhage caused by neurofibromas of the cauda equina. An examination of the literature revealing 13 similar cases and an analysis of this case ...showing three neurofibromas of the cauda equina prompted an hypothesis emphasizing the origin of bleeding and the difficulties associated with a correct diagnosis.
The isolated retroperitoneal malignant schwannoma unassociated with Von Recklinghausen's disease is an unusual neoplasm, representing 0.01% of all retroperitoneal malignant neoplasms, with a poor ...prognosis, and an average survival at 5 years of 50% in patients treated by radical exeresis. At present, it is impossible, without histologic and immunohistochemical examinations, to differentiate it from other isolated retroperitoneal sarcomatous neoplasms. The authors report a case of retroperitoneal malignant schwannoma 20 cm in diameter in a 62-year-old woman surgically treated by radical exeresis. Postoperative complications were absent, and the patient, discharged from the hospital on the 12th postoperative day, died 8 months later of diffuse metastases, without local relapse. Despite the patient's short survival, the authors believe radical surgery to be the best therapeutic choice. Only surgery can establish a final diagnosis and can offer the best chance of survival and a significant and sometimes prolonged relief of symptomatology.
Cloud technologies can nowadays be considered as commodities. The possibility of getting access to storage, computing and networking virtual resources empowers any business that needs dynamic IT ...capabilities. The Cloud Management Broker (CMB) plays a crucial role to handle heterogeneous virtualized cloud resources in order to offer a unique set of interfaces to the cloud users. Moreover, the CMB is in charge of optimizing the usage of the cloud resources, satisfying the requirements declared by the users. This paper proposes a novel multi-cloud resource allocation algorithm, based on a Markov Decision Process (MDP), capable of dynamically assigning the resources requests to a set of IT resources (storage or computing resources), with the aim of maximizing the expected CMB revenue. Simulation results show the feasibility and the higher performances obtained by the proposed algorithm, compared to a greedy approach.
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