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Although histologically benign, adamantinomatous craniopharyngioma (AC) pediatric brain tumor is a locally aggressive disease that frequently determines symptoms and hormonal dysfunctions related to the mass effect on the surrounding structures. Another typical feature of this benign neoplasm is the presence of voluminous liquid cysts frequently associated with the solid component. Even if studies have been devoted to the proteomic characterization of the tumor intracystic fluid, poor explorations have been performed on its solid part, principally investigated by transcriptomics technologies. In the present study, seven specimens of AC whole tumor tissue have been analyzed by LC-MS for a preliminary assessment of the proteomic profile by a top-down/bottom-up integrated approach. Thymosin beta 4, ubiquitin, calmodulin, S100 proteins, prothymosin alpha isoform 2, alpha-defensins 1-4, and fragments largely belonging to vimentin, hemoglobin, and glial fibrillary acidic protein characterized the intact proteome. The identification of alpha-defensins, formerly characterized in AC intracystic fluid, reinforces the hypothesis of a role for inflammation in tumor pathogenesis. A total number of 1798 unique elements were identified by a bottom-up approach with a special focus on the 433 proteins commonly characterized in the 85.7% of the samples analyzed. Their gene ontology classification evidenced the involvement of the adherence system, intermediate filaments, and actin cytoskeleton in tumor pathogenesis and of elements part of the Wnt, FGF, and EGFR signaling pathways. In addition, proteins involved in calcium modulation, innate immunity, inflammation, CCKR and integrin signaling, and gonadotropin-releasing hormone receptor pathways were also outlined. Further than confirming proteomic data previously obtained on AC intracystic fluid, these results offer a preliminary overview of the AC whole tissue protein phenotype, adding new hints towards the comprehension of this still obscure pediatric brain tumor.

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Planar AdS black holes with axionic charge have finite DC conductivity due to momentum relaxation. We obtain a new family of exact asymptotically AdS$_4$ black branes with scalar hair, carrying magnetic and axion charge, and we study the thermodynamics and dynamic stability of these, as well as of a number of previously known electric and dyonic solutions with axion charge and scalar hair. The scalar hair for all solutions satisfy mixed boundary conditions, which lead to modified holographic Ward identities, conserved charges and free energy, relative to those following from the more standard Dirichlet boundary conditions. We show that properly accounting for the scalar boundary conditions leads to well defined first law and other thermodynamic relations. Finally, we compute the holographic quantum effective potential for the dual scalar operator and show that dynamical stability of the hairy black branes is equivalent to positivity of the energy density., Comment: 54 pages, 11 figures; v2 references and one table added. Version published in JHEP

Survivors of brain tumors are faced with a high risk for a wide range of cognitive problems and learning difficulties. These problems are caused by the lesion itself and its surgical removal as well as by the treatments to follow (chemo- and/or radiation therapy). A few recent studies have indicated that children with brain tumors (BT) might exhibit cognitive problems already at diagnosis, i.e. before the start of any medical treatment. The aim of the present study was to investigate the "baseline" neuropsychological profile in children with BT in comparison to children with an oncological diagnosis not involving the central nervous system (CNS). 20 children with BT and 27 children with an oncological disease without involvement of the CNS (age range: 6.1 to 16.9 years) were evaluated with an extensive battery of neuropsychological tests tailored to the patient's age. Furthermore, the child and its parents completed self-report questionnaires about emotional functioning and quality of life. In both groups, tests were administered before any therapeutic intervention such as surgery, chemotherapy or irradiation. Groups were comparable regarding age, gender and social economic status. Compared to the CG, patients with BTs performed significantly worse in tests of working memory, verbal memory and attention. In contrast the areas of perceptual reasoning, processing speed and verbal comprehension were preserved at this time. Younger children with BT were especially disadvantaged. Compared to aged matched children with malignancies not involving the CNS and older BT patients the young BT patients showed deficits in attention, working memory and verbal memory measures. Our results highlight the need for cognitive assessments and interventions early in the treatment process in order to minimize or even prevent academic difficulties as patients return to school.

Understanding the role of Thymosins proteoforms in CNS diseases

Preliminary investigation on the intact proteome and peptidome of medulloblastoma in vitro cell culture by LC-high resolution-MS

Top-down/bottom-up LC-MS integrated proteomic platforms for molecular fingerprinting of adamantinomatous craniopharyngioma pediatric brain tumor

Hemorphins cytotoxic effect on medulloblastoma DAOY cells: a proteomic investigation by top-down approach

Proteomic characterization of adamantinomatous craniopharyngioma pediatric brain tumor

We obtain the gravitational and electromagnetic field of a spinning radiation beam-pulse (a gyraton) in minimal five-dimensional gauged supergravity and show under which conditions the solution preserves part of the supersymmetry. The configurations represent generalizations of Lobatchevski waves on AdS with nonzero angular momentum, and possess a Siklos-Virasoro reparametrization invariance. We compute the holographic stress-energy tensor of the solutions and show that it transforms without anomaly under these reparametrizations. Furthermore, we present supersymmetric gyratons both in gauged and ungauged five-dimensional supergravity coupled to an arbitrary number of vector supermultiplets, which include gyratons on domain walls., Comment: 25 pages, no figures, uses JHEP3.cls. Final version to appear in CQG

We investigate the propagation of arbitrarily coupled scalar fields on the $N$-dimensional hyperbolic space ${\mathbb H}^N$. Using the $\zeta$-function regularization we compute exactly the one loop effective action. The vacuum expectation value of quadratic field fluctuations and the one loop renormalized stress tensor are then computed using the recently proposed direct $\zeta$-function technique. Our computation tests the validity of this approach in presence of a continuous spectrum. Our results apply as well to the $N$-dimensional anti-de Sitter spacetime, whose appropriate euclidean section is the hyperbolic space ${\mathbb H}^N$., Comment: RevTeX, 18 pages, no figures, references added, definition of y explained, typos in the Appendix corrected, final version to appear in Nucl. Phys. B

A general class of axionic and electrically charged black holes for a self-interacting scalar field nonminimally coupled to Einstein gravity with a negative cosmological constant is presented. These solutions are the first examples of black holes with an arbitrary nonminimal coupling $\xi$ in four dimensions. Moreover, due to the presence of two three-forms fields, the topology of the horizon of these black holes is planar. We discuss some properties of these solutions electing particular values of the nonminimal coupling parameter. A special case arises when $\xi=1/4$, for which the gravitational field is confined in a region close to the event horizon. We also show that these black holes emerge from stealth AdS configurations as the axionic fields are switched on, and that they can be generated through a Kerr-Schild transformation. Finally, in the appendix, we extend these results to arbitrary dimension., Comment: 23 pages

We consider four dimensional stationary and axially symmetric spacetimes for conformally coupled scalar-tensor theories. We show that, in analogy to the Lewis-Papapetrou problem in General Relativity (GR), the theory at hand can be recast in an analogous integrable form. We give the relevant rod formalism, introduced by Weyl for vacuum GR, explicitly giving the rod structure of the black hole of Bocharova et al. and Bekenstein (BBMB), in complete analogy to the Schwarzschild solution. The additional scalar field is shown to play the role of an extra Weyl potential. We then employ the Ernst method as a concrete solution generating example to obtain the Taub-NUT version of the BBMB hairy black hole, with or without a cosmological constant. We show that the anti-de Sitter hyperbolic version of this solution is free of closed timelike curves that plague usual Taub-NUT metrics, and thus consists of a rotating, asymptotically locally anti-de Sitter black hole. This stationary solution has no curvature singularities whatsoever in the conformal frame, and the NUT charge is shown here to regularize the central curvature singularity of the corresponding static black hole. Given our findings we discuss the anti-de Sitter hyperbolic version of Taub-NUT in four dimensions, and show that the curvature singularity of the NUT-less solution is now replaced by a neighboring chronological singularity screened by horizons. We argue that the properties of this rotating black hole are very similar to those of the rotating BTZ black hole in three dimensions., Comment: 27 pages, 1 figure

In view of the recent interest in reproducing holographically various properties of conformal fluids, we review the issue of vorticity in the context of AdS/CFT. Three-dimensional fluids with vorticity require four-dimensional bulk geometries with either angular momentum or nut charge, whose boundary geometries fall into the Papapetrou--Randers class. The boundary fluids emerge in stationary non-dissipative kinematic configurations, which can be cyclonic or vortex flows, evolving in compact or non-compact supports. A rich network of Einstein's solutions arises, naturally connected with three-dimensional Bianchi spaces. We use Fefferman--Graham expansion to handle holographic data from the bulk and discuss the alternative for reversing the process and reconstruct the exact bulk geometries., Comment: 37 pages, Latex, Review to appear in the proceedings of the Corfu Summer Institute 2011: School and workshops on elementary particle physics and gravity, September 4-18, 2011, Corfu, Greece

Static, charged black holes in the presence of a negative cosmological constant and with a planar horizon are found in four dimensions. The solutions have scalar secondary hair. We claim that these constitute the planar version of the Martinez-Troncoso-Zanelli black holes, only known up to now for a curved event horizon in four dimensions. Their planar version is rendered possible due to the presence of two, equal and homogeneously distributed, axionic charges dressing the flat horizon. The solutions are presented in the conformal and minimal frame and their basic properties and thermodynamics analysed. Entertaining recent applications to holographic superconductors, we expose two branches of solutions: the undressed axionic Reissner-Nordstrom-AdS black hole, and the novel black hole carrying secondary hair. We show that there is a critical temperature at which the (bald) axionic Reissner-Nordstrom-AdS black hole undergoes a second order phase transition to the hairy black hole spontaneously acquiring scalar hair., 21 pages, 4 figures

Using the blackfold approach, we study new classes of higher-dimensional rotating black holes with electric charges and string dipoles, in theories of gravity coupled to a 2-form or 3-form field strength and to a dilaton with arbitrary coupling. The method allows to describe not only black holes with large angular momenta, but also other regimes that include charged black holes near extremality with slow rotation. We construct explicit examples of electric rotating black holes of dilatonic and non-dilatonic Einstein-Maxwell theory, with horizons of spherical and non-spherical topology. We also find new families of solutions with string dipoles, including a new class of prolate black rings. Whenever there are exact solutions that we can compare to, their properties in the appropriate regime are reproduced precisely by our solutions. The analysis of blackfolds with string charges requires the formulation of the dynamics of anisotropic fluids with conserved string-number currents, which is new, and is carried out in detail for perfect fluids. Finally, our results indicate new instabilities of near-extremal, slowly rotating charged black holes, and motivate conjectures about topological constraints on dipole hair., Comment: 61 pages. v2: improved version. v3: final published version

It has recently been proposed that the strong coupling behaviour of quantum field theories on a non-dynamical black hole background can be described, in the context of the AdS/CFT correspondence, by a competition between two gravity duals: a black funnel and a black droplet. We present here thermal equilibrium solutions which represent such spacetimes, providing the first example where the thermal competition between the gravity duals can be studied. The solutions correspond to a special family of charged AdS C-metrics. We compute the corresponding Euclidean actions and find that the black funnel always dominates the canonical ensemble in our example, meaning that the field theory does not undergo a phase transition., 37 pages, 12 figures

The supersymmetric solutions of N=2, D=4 minimal ungauged and gauged supergravity are classified according to the fraction of preserved supersymmetry using spinorial geometry techniques. Subject to a reasonable assumption in the 1/2-supersymmetric time-like case of the gauged theory, we derive the complete form of all supersymmetric solutions. This includes a number of new 1/4- and 1/2-supersymmetric possibilities, like gravitational waves on bubbles of nothing in AdS_4., 70 pages, JHEP3. v2: new explicit solutions for G_0 = 0 and reference added

We present non-extremal magnetic black string solutions in five-dimensional gauged supergravity. The conformal infinity is the product of time and S^1xS_h, where S_h denotes a compact Riemann surface of genus h. The construction is based on both analytical and numerical techniques. We compute the holographic stress tensor, the Euclidean action and the conserved charges of the solutions and show that the latter satisfy a Smarr-type formula. The phase structure is determined in the canonical ensemble, and it is shown that there is a first order phase transition from small to large black strings, which disappears above a certain critical magnetic charge that is obtained numerically. For another particular value of the magnetic charge, that corresponds to a twisting of the dual super Yang-Mills theory, the conformal anomalies coming from the background curvature and those arising from the coupling to external gauge fields exactly cancel. We also obtain supersymmetric solutions describing waves propagating on extremal BPS magnetic black strings, and show that they possess a Siklos-Virasoro reparametrization invariance., Comment: 40 pages, 7 figures, JHEP3. v2: minor corrections, 2 references added. v3: typos in holographic stress tensor corrected, 3 references added

We review the issue of chronology protection and show how string theory can solve it in the half BPS sector of AdS/CFT. According to the LLM prescription, half BPS excitations of AdS_5 x S^5 geometries in type IIB string theory can be mapped into free fermion configurations. We show that unitarity of the theory describing these fermions is intimately related to the protection of the chronology in the dual geometries., 7 pages, 7 figures, contribution to the proceedings of the RTN workshop "Constituents, Fundamental Forces and Symmetries of the Universe", Corfu, Greece, 20-26 September 2005

We consider various models of three-dimensional gravity with torsion or nonmetricity (metric affine gravity), and show that they can be written as Chern-Simons theories with suitable gauge groups. Using the groups ISO(2,1), SL(2,C) or SL(2,R) x SL(2,R), and the fact that they admit two independent coupling constants, we obtain the Mielke-Baekler model for zero, positive or negative effective cosmological constant respectively. Choosing SO(3,2) as gauge group, one gets a generalization of conformal gravity that has zero torsion and only the trace part of the nonmetricity. This characterizes a Weyl structure. Finally, we present a new topological model of metric affine gravity in three dimensions arising from an SL(4,R) Chern-Simons theory., Comment: 24 pages, uses JHEP3.cls. Published version

Endoscopic third-ventriculostomy (ETV) became the treatment of choice for non-communicating hydrocephalus and its effectiveness is largely reported. On the contrary, specific articles on complications and failures of this technique are very rare and this review aims at supplying further information about it. Therefore, an analysis of the main and up-to-date series is made and exhaustive data about complications and failures of ETV and about their incidence are obtained. The overall frequency rate of complications is 6-20%. Their severity may vary either because of the length of the damage (transient or permanent) or the value of the involved structures (basilar artery, areas of the CNS, hypothalamus) or the importance of the injury (from subclinical sequelae to fatal complications). Moreover, this study showed both the risk that the endoscopic procedure must be suspended (intra-operative failure) and the risk of an early (before 1 month) or delayed (even some years after the intervention) narrowing of the ventriculostomy. The rate of and the reasons for failure have been analysed and the success of a second ETV has been estimated. The results of this analysis suggest that the children proposed for ETV are carefully selected and meticulously studied during the follow-up.

We deepen and refine the classification of supersymmetric solutions to N=2, D=4 gauged supergravity obtained in a previous paper. In the case where the Killing vector constructed from the Killing spinor is timelike, it is shown that the nonlinear partial differential equations determining the BPS solutions can be derived from a variational principle. The corresponding action enjoys a solution-generating PSL(2,R) symmetry. In certain subcases the system reduces to different known theories, like two-dimensional dilaton gravity or the dimensionally reduced gravitational Chern-Simons theory. We find new supersymmetric solutions including, among others, kinks that interpolate between two AdS_4 vacua, electrovac waves on anti-Nariai spacetimes, or generalized Robinson-Trautman solutions. In the case where the Killing vector is null, we obtain a complete classification. The one quarter and one half supersymmetric solutions are determined explicitely, and it is shown that the fraction of three quarters of supersymmetry cannot be preserved. Finally, the general lightlike configuration is uplifted to eleven-dimensional supergravity., 36 pages, JHEP class, minor errors corrected

In this article we study giant gravitons in the framework of AdS/CFT correspondence. First, we show how to describe these configurations in the CFT side using a matrix model. In this picture, giant gravitons are realized as single excitations high above a Fermi sea, or as deep holes into it. Then, we give a prescription to define quasi-classical states and we recover the known classical solution associated to the CFT dual of a giant graviton that grows in AdS. Second, we use the AdS/CFT dictionary to obtain the supergravity boundary stress tensor of a general state and to holographically reconstruct the bulk metric, obtaining the back reaction of space-time. We find that the space-time response to all the supersymmetric giant graviton states is of the same form, producing the singular BPS limit of the three charge Reissner-Nordstr\"om-AdS black holes. While computing the boundary stress tensor, we comment on the finite counterterm recently introduced by Liu and Sabra, and connect it to a scheme-dependent conformal anomaly., Comment: 28 pages, JHEP3 class. v2: typos corrected and references added

The authors report on the case of a low-grade fibromyxoid sarcoma (LGFMS) with giant rosettes in a 4-year-old boy. The tumor arose in the paravertebral region and had infiltrated the vertebral canal between L2 and S1. A review of the literature indicates that this is one of the youngest patients diagnosed with a tumor of this type, and spinal involvement had never been reported with LGFMS.

We consider 1/2 BPS excitations of AdS(5)xS(5) geometries in type IIB string theory that can be mapped into free fermion configurations according to the prescription of Lin, Lunin and Maldacena (LLM). It is shown that whenever the fermionic probability density exceeds one or is negative, closed timelike curves appear in the bulk. A violation of the Pauli exclusion principle in the phase space of the fermions is thus intimately related to causality violation in the dual geometries., Comment: 4 pages, 1 figure. v2: clarifications on the proof and comments on curvature singularity added. v3: final version to appear in Class. Quantum Grav

The decision making process for patients with sylvian fissure arachnoid cysts still represents a challenge for the neurosurgeon. A high proportion of the patients is indeed asymptomatic, in spite of neuroimaging signs of apparently increased intracranial pressure (ICP). The aim of the present study was to evaluate the usefulness of prolonged ICP recording in the preoperative work-out.Twelve children (11 M/1 F) harboring temporal arachnoid cysts were investigated (men age 6.3 years). According to Galassi classification they were subdivided into 3 groups. Group I included 3 patients with Type I cysts; group II comprised 6 children with Type II cysts; group III consisted of 3 children with Type III cysts. An extensible silicone microprocessor (Codman ), developed for continuous ICP recording, was implanted intraparenchymally, adjacent to the major extension of the cyst. The collected information was cable unloaded to a PC and stored. All the patients underwent a minimum of 48 hours to a maximum of 72 hours ICP continuous check. Ten mmHg was arbitrarily chosen as the upper normal limit of ICP in resting conditions and the patients were classified according to the percentile distribution of their ICP daily and nightly pressure values.ICP recordings were in the normal range in all the 3 children with Type I cysts (49-86%10 mmHg during the entire recording), in spite of the fact that 2 of them were apparently symptomatic. Three of the 6 children with a Type II temporal cyst had elevated ICP values (69-99%10 mmHG), even though they had an incidental (1 case) or prenatal (2 cases) diagnosis. The remaining 3 patients had normal ICP values for more than 70% of the recording time period. Two of the 3 patients with type III temporal arachnoid cysts had almost constantly abnormal ICP values (95=99%10 mmHg); conversely the third patient showed normal ICP values for more than 80% of the recording time period. Five patients were operated on; in 4 of them the surgical indication was based on ICP recordings (2 of the 3 children with a Type II cyst and increased ICP and the 2 patients with a Type III cyst and increased ICP). The last child, harboring a Type I cyst, was operated on under parents request, as a preventive measure. At a mean follow-up of 10.1 months all the patients operated on are in excellent clinical conditions; 1 of them (Type II cyst) initially submitted to craniotomy and cystic membrane excision needed a subdural-peritoneal shunt implant 3 months after surgery for the appearance of a symptomatic subdural hygroma on the side of the cyst. Postoperative CT showed signs of brain expansion in the 2 patients operated on for a Type III cyst, and in the patients operated on for a Type I cyst.With the limit of the relatively small series here presented, prolonged ICP recording appeared to be an important preoperative tool to rule out the necessity of operating on children with Type I cysts. Furthermore, it was particularly useful in the decision-making process for children with Type III cysts. In cases of Type II lesions, the investigation resulted less discriminating, though the ICP monitoring contributed to find out those patients in whom surgery was indicated in spite of the absence of symptoms.

We classify all supersymmetric solutions of minimal gauged supergravity in four dimensions. There are two classes of solutions that are distinguished by the norm of the Killing vector constructed from the Killing spinor. If the Killing vector is timelike, the solutions are determined by the geometry of a two-dimensional base-manifold. When it is lightlike, the most general BPS solution is given by an electrovac AdS travelling wave. This supersymmetric configuration was previously unknown. Generically the solutions preserve one quarter of the supersymmetry. Also in the timelike case we show that there exist new BPS solutions, which are of Petrov type I, and are thus more general than the previously known type D configurations. These geometries can be uplifted to obtain new solutions of eleven-dimensional supergravity., 29 pages, LaTeX, v2: discussion of maximally supersymmetric solutions and references added, v3: published version

Several literature reports have demonstrated that cardiovascular disease is one of the most frequent pathologies in patients with spinal cord injury.The aim of this study is to reveal changes in the lipid profile in non-obese children with spina bifida/myelomeningocele (MMC).The original results demonstrate the necessity of metabolic surveillance in these patients. Daily physical activity must be ensured early on frequency in non-able-bodied children in order to prevent changes in seric lipoproteins.

We generalize the classification of all supersymmetric solutions of pure N=2, D=4 gauged supergravity to the case when external sources are included. It is shown that the source must be an electrically charged dust. We give a particular solution to the resulting equations, that describes a Goedel-type universe preserving one quarter of the supersymmetries., Comment: 6 pages, Latex. v2: references and footnote added. v3: introduction expanded, minor corrections, references added. Final version

Moyamoya is a progressive occlusive cerebrovascular disease which affects the distal internal carotid artery and its main branches, and is characterized, from a clinical point of view, by a variety of ischemic manifestations ranging from transient ischemic attacks (TIA) to stroke. Although considered until recently as almost specific of Japanese population, it can also affect individuals of different origin, and there is an increasing interest for this rare disease in Western medical literature. Nonetheless papers dealing with moyamoya disease in pediatric age are still very rare and almost exclusively limited to isolated case reports. These considerations prompted us to review our experience with the diagnosis and treatment of such unusual disease.Nine children (seven months to nine years of age) presented with clinical manifestations of occlusive cerebrovascular disease (TIAs or stroke), epilepsy, and/or psychomotor retardation. Neuroradiological investigation, and in particular cerebral angiography, demonstrated the classical pattern of moyamoya disease. Eight of these children underwent cerebral revascularization utilizing the encephalomyosynangiosis (EMS) technique, with a total of 14 operations (six on both sides, two on one side).There was no mortality neither major morbidity related to surgery. One patient with renovascular hypertension, died at home approximately six months after a successful operation, probably from cerebral hemorrhage. In all the cases postoperative angiography revealed a marked improvement in cerebral circulation. However, in spite of the apparently normalized cerebral blood flow, clinical manifestations were affected less significantly. In fact, there was only minimal if any improvement in children operated on with an already established hemiplegia; whereas improvement in motor ability was obtained in those presenting with hemiparesis or TIAs, as well as in epilepsy and psychomotor retardation.On the grounds of our results we conclude that cerebral revascularization (by means of a simple operation like the EMS) in children with moyamoya disease is worthwhile, provided that the operation be performed before irreversible cerebral damage is established; however, even under these circumstances the operation can at least stop the progression of the disease.

The extreme limit of a class of D-dimensional black holes is revisited. In the static limit, it is shown that well defined extremal limiting procedure exists and it leads to new solutions of the type AdS2 times constant curvature symmetric spaces., Comment: 8 pages, proceedings of Londrina Conference, April 2000, Londrina, Brazil

The boundary terms in the Hamiltonian, in the presence of horizons, are carefully analyzed in a simple 2D theory admitting AdS black holes. The agreement between the euclidean approach and Cardy's formula is obtained modulo certain assumptions on the spectrum of the Virasoro's algebra. There is no discrepancy factor "square root of 2" once the appropriate boundary conditions are properly recognized. The peculiar features of gravity, that the on-shell Hamiltonian is determined by boundary terms, is the reason of the mentioned agreement., 6 pages, Latex2e document, v2 typos corrected, one reference added

We review some aspects of the quantum field theory of a conformally coupled scalar field on the singular background obtained in the massless limit of a class of toroidal black holes. The stress-tensor and its back reaction on the metric are computed, using point-splitting regularization, in the cases of transparent, Neumann and Dirichlet boundary conditions. We find that the quantum fluctuations generate an event horizon which hides the singularity. The resulting object can be interpreted as a long-lived remnant. We discuss the relevance of this result in the context of the cosmic censorship conjecture, and in connection to the end point of the quantum evaporation process.