Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 134
Filtrar
1.
J Gambl Stud ; 39(3): 1337-1354, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35908025

RESUMO

AIM: Measuring the phenomenon of gambling and Internet addiction, with analysis of attitudes and psychophysical consequences among nurses working in different care settings. METHODS: An observational, cross sectional, multicenter study was conducted from April to September 2020. Participants' socio-demographic information, the "Internet Addiction Test" (IAT) scale, and the "South Oaks Gambling Screen" (SOGS) were collected in order to assess the overuse of and whether an individual has a problematic relationship with gambling, respectively. RESULTS: 502 nurses were enrolled in the study. Significant correlations were found (p < .001) between the IAT score and gender, number of years of work experience, job role, educational qualification; and between the SOGS and gender, number of years of work experience, job role and regions of Italy. CONCLUSIONS: The study highlighted an emerging social problem, and the results may be just the tip of the iceberg. Given the lack of knowledge of these phenomena and a high percentage of people who suffer from them but are afraid to admit it and get help, this study could also be useful in expanding knowledge and allow more professionals to get help and learn about possible treatments and cures for the resolution of these addictions.


Assuntos
Comportamento Aditivo , Jogo de Azar , Humanos , Jogo de Azar/psicologia , Projetos Piloto , Estudos Transversais , Transtorno de Adição à Internet , Comportamento Aditivo/epidemiologia , Itália , Atenção à Saúde , Internet
2.
Phys Rev Lett ; 128(10): 103201, 2022 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-35333068

RESUMO

Multimode optical cavities can be used to implement interatomic interactions which are highly tunable in strength and range. For bosonic atoms trapped in an optical lattice we show that, for any finite range of the cavity-mediated interaction, quantum self-bound droplets dominate the ground state phase diagram. Their size and in turn density is not externally fixed but rather emerges from the competition between local repulsion and finite-range cavity-mediated attraction. We identify two different regimes of the phase diagram. In the strongly glued regime, the interaction range exceeds the droplet size and the physics resembles the one of the standard Bose-Hubbard model in a (self-consistent) external potential, where in the phase diagram two incompressible droplet phases with different filling are separated by one with a superfluid core. In the opposite weakly glued regime, we find instead direct first order transitions between the two incompressible phases, as well as pronounced metastability. The cavity field leaking out of the mirrors can be measured to distinguish between the various types of droplets.

3.
Hematol Oncol ; 37(4): 434-437, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31465530

RESUMO

The conventional thrombotic risk stratification in essential thrombocythemia (ET) distinguishes patients in two risk groups based on previous thrombosis and age (< or >60). The IPSET-thrombosis takes into account four risk factors: age greater than 60 years and the presence of CV risk factors, thrombosis history and JAK2 V617F presence. The revised IPSET-thrombosis uses three adverse variables to delineate four risk categories: age greater than 60, thrombosis history, and JAK2 V617F presence. We compared different risk models in the estimation of thrombotic risk in 191 patients with ET and the role of specific driver mutations affecting overall survival, according to thrombotic risk. We also evaluated the mutational status of patients showing history of thrombosis or cardiovascular events versus patients who did not. Finally, we verified whether the thrombotic risk had a significant impact on survival in our ET patients. The data analysis has been performed through the conventional statistics and overall survival estimated by using the Kaplan-Meyer method. Interestingly, either using the traditional system for thrombotic risk or the IPSET-t prognostic score or the current stratification for the thrombotic risk, high-risk patients are always highly represented. This evidence is of note, being the high-risk category indicated for cytoreduction, affecting quality of life, despite the good overall prognosis of patients with ET diagnosis in general. The analysis of overall survival in our patients, according to different models for thrombotic risk, highlighted the poor prognosis of high-risk patients compared with those with a lower thrombotic risk, in particular when using traditional stratification and current stratification. In conclusion, the occurrence of thrombotic or cardiovascular events represents one of the most severe complications at diagnosis or during follow-up of ET despite current recommendations, having a significant impact on morbidity and survival.


Assuntos
Índice de Gravidade de Doença , Trombocitemia Essencial/complicações , Trombofilia/etiologia , Trombose/etiologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Calreticulina/genética , Feminino , Seguimentos , Humanos , Incidência , Janus Quinase 2/genética , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Mutação de Sentido Incorreto , Prognóstico , Receptores de Trombopoetina/genética , Recidiva , Estudos Retrospectivos , Medição de Risco/métodos , Fatores de Risco , Trombocitemia Essencial/genética , Trombocitemia Essencial/mortalidade , Trombofilia/genética , Trombose/epidemiologia , Adulto Jovem
4.
Phys Rev Lett ; 114(24): 245301, 2015 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-26196983

RESUMO

We show that the critical velocity of a superfluid flow through a penetrable barrier coincides with the onset of the analog black-hole lasing effect. This dynamical instability is triggered by modes resonating in an effective cavity formed by two horizons enclosing the barrier. The location of the horizons is set by v(x)=c(x), with v(x),c(x) being the local fluid velocity and sound speed, respectively. We compute the critical velocity analytically and show that it is univocally determined by the configuration of the horizons. In the limit of broad barriers, the continuous spectrum at the origin of the Hawking-like radiation and of the Landau energetic instability is recovered.

5.
Phys Biol ; 10(4): 040301, 2013 08.
Artigo em Inglês | MEDLINE | ID: mdl-23912807

RESUMO

More than 60 years of biochemical and biophysical studies have accustomed us to think of proteins as highly purified entities that act in isolation, more or less freely diffusing until they find their cognate partner to bind to. While in vitro experiments that reproduce these conditions largely remain the only way to investigate the intrinsic properties of molecules, this approach ignores an important factor: in their natural milieu , proteins are surrounded by several other molecules of different chemical nature, and this crowded environment can considerably modify their behaviour. About 40% of the cellular volume on average is occupied by all sorts of molecules. Furthermore, biological macromolecules live and operate in an extremely structured and complex environment within the cell (endoplasmic reticulum, Golgi apparatus, cytoskeletal structures, etc). Hence, to further complicate the picture, the interior of the cell is by no means a simply crowded medium, rather, a most crowded and confining one. In recent times, several approaches have been developed in the attempt to take into account important factors such as the ones mentioned above, at both theoretical and experimental levels, so that this field of research is now emerging as one of the most thriving in molecular and cell biology (see figure 1). [Formula: see text] Figure 1. Left: number of articles containing the word 'crowding' as a keyword limited to the biological and chemical science domains (source: ISI Web of Science). The arrow flags the 2003 'EMBO Workshop on Biological Implications of Macromolecular Crowding' (Embo, 2012). Right: number of citations to articles containing the word 'crowding' limited to the same domains (bars) and an exponential regression curve (source: Elsevier Scopus). To promote the importance of molecular crowding and confinement and provide researchers active in this field an interdisciplinary forum for meeting and exchanging ideas, we recently organized an international conference held in Ascona from 10 to 14 June 2012. In the unique scenario of the Maggiore lake and absorbed in the magic atmosphere of the Centro Stefano Franscini (CSF) at Monte Verità, we enjoyed three-and-a-half days of intense and inspiring activity, where not only many of the most prominent scientists working on macromolecular crowding, but also experts in closely related fields such as colloids and soft matter presented their work. The meeting was intended and has been organized to bring theoreticians and experimentalists together in the attempt to promote an active dialogue. Moreover, we wanted different disciplines to be represented, notably physics and chemistry, besides biology, as cross-fertilization is proving an increasingly fundamental source of inspiration and advancement. This issue of Physical Biology (PB) features a selection of the oral contributions presented at the conference, expanded in the form of research or review articles. PB, one of the scientific journals of the Institute of Physics (IOP), is one of the most dynamic and lively forums active at the interface between biology on one side, and physics and mathematics on the other. As its mission is stated by IOP, PB 'focuses on research in which physics-based approaches lead to new insights into biological systems at all scales of space and time, and all levels of complexity'. For these reasons, and also in view of its high reputation and broad readership, PB appears to be the ideal place for disseminating the thriving pieces of research presented at the conference. We are extremely grateful to PB and its kind and efficient editorial staff who helped make this issue a great scientific follow-up to the conference. The opening lecture of the conference, the first of four day-opening keynote lectures, was given by Allen P Minton from NIH (USA), possibly the most influential among the pioneers in the field. He provided a lucid and well-thought-out overview of the concept of macromolecular crowding through an exhaustive chronological account of the major milestones. It is clear that the concept of excluded volume as a key factor remains central to the concept of molecular crowding. As a consequence, simple descriptive paradigms borrowed essentially from colloid physics may still provide useful tools to understand the subtle effects of crowding and confinement in living matter. The contiguity between crowding, colloids and soft matter further emerged as an important concept in the course of the conference in several theoretical lectures and a few experimental ones. Dave Thirumalai, from the University of Maryland (USA), one of the most active theoreticians in the field of theoretical biophysics, outlined scaling theories, concepts from colloid literature and different simulation techniques to describe scenarios for crowding-induced changes in the structure and dynamics of proteins and RNA. In particular, he showed the importance of the shape of crowding particles in affecting folding oligomerization of amyloidogenic peptides. Johannes Schöneberg, from IMPRS, Mathematics Institute (Germany), illustrated ReaDDy , a newly developed particle-based simulation software tool for reaction-diffusion dynamics, developed in the group of Frank Noe at EMPRS. He showed that ReaDDy makes it possible to bridge the gap between soft matter and molecular dynamics (MD) simulations on the one hand and particle-based stochastic reaction-diffusion simulations on the other. We asked Johannes to organize a tutorial session to lead interested participants into the package and 'get their hands wet' under the guidance of the developers. The tutorial session was indeed successful and the broad possibilities offered by the simulation toolkit appeared to be clear to the participants. Paolo De Los Rios, from the Ecole Polytechnique Fédérale de Lausanne (EPFL, Switzerland), examined the complexity of the effects caused by crowding conditions from the point of view of statistical physics. Starting from a modification of the well-known Smoluchowski approach to calculate the encounter rate of diffusion-limited reactions, he showed how more realistic situations accounting for crowding effects could be treated equally well on the same theoretical grounds. This talk marked an important point in the conference as it reinforced the idea that simple models of theoretical physics still have the power to provide inspiring results in spite of the intrinsic simplifications of such theoretical approaches. Along the same lines, Nicolas Dorsaz, from the University of Cambridge (UK), proposed an extension of the Smoluchowski framework that incorporates repulsive and attracting interactions between the reactants. This approach was illustrated by reaction rates obtained from event-driven Brownian dynamics and dynamical Monte Carlo simulations. Another striking example of the physical subtleties associated with modelling crowding effects was provided by Jeffrey Skolnick, from the Georgia Institute of Technology (USA). He examined the role of hydrodynamic interactions in the self-organization of biological assemblies in the presence of crowding. His results strongly suggest that hydrodynamic interactions greatly affect the kinetics of self-assembly reactions, so that including them in the picture appears crucial for understanding the dynamics of biological systems in vivo . Margareth Cheung, from the University of Houston (USA), emphasized that how the crowded environment inside a cell affects the structural conformation of a protein with a spherical shape is a vital question because the geometry of proteins and protein-protein complexes are far from globules in vivo . Her work demonstrates the malleability of 'native' proteins and implies that crowding-induced shape changes may be important for protein function and malfunction in vivo . Huan-Xiang Zhou, from the Florida State University (USA), focused on atomistic simulations of protein folding and binding under crowding conditions. His lab has developed a post-processing method that allows the atomistic representation of proteins in folding and binding processes under crowding. A comparison with experimental results was also presented. Other lecturers pointed out that there are still aspects not entirely explored in the effects of both crowding and confinement. As suggested in the talk by Gary Pielak, from the University of North Carolina (USA), the currently used synthetic crowding agents are far from being satisfactory in replicating naturally occurring effects associated with crowded environments. For example, non-specific binding seems to play a subtle role in the cell, as natural macromolecules can induce both stabilization and destabilization when used as crowders. It is indeed possible to fine-tune the effect of proteins, as crowders, on the stability of other proteins. Another aspect that became clear is that new, more powerful methods need to be developed to study the effect of crowding, but even more to compare crowding and confinement. Indeed, it appeared clear from the lecture by Pierandrea Temussi, from the University of Naples (Italy), that a reliable comparison of the effects of crowding and confinement on the stability of proteins can only be based on the measurement of the whole stability curve of the same protein. Controversial aspects do not pertain only to the influence of crowding on protein stability, but also to aggregation phenomena in natural fluids. Domenico Sanfelice, from NIMR (London, UK), reported an interesting case of the apparent influence of crowding on aggregation. Hen egg white, a possible natural medium to study macromolecules in crowded conditions can dramatically increase the aggregation kinetics of proteins with an inbuilt tendency to associate. By carefully dissecting the phenomenology, it was shown that only part of this effect is due to crowding, while another factor playing an important role is the interaction withproteins from the milieu . In other words, high-molecular-weight glycoproteins can act as efficient molecular seeds for aggregation. A special topic of great relevance in the conference appeared to be the direct study of crowding in living systems. Alan Verkman, from the University of California, San Francisco (USA), one of the world's leading scientific personalities in the field of experimental investigation of crowding and confinement, was invited to give the second plenary lecture devoted to the experimental study of crowding effects in vivo . In his keynote lecture, Dr Verkman led us on a wide and compelling tour, exploring the main experimental approaches to study molecular crowding in and around cells. After a thorough examination of methods such as fluorescence recovery after photo-bleaching, fluorescence correlation spectroscopy, photo-activation localization microscopy and stochastic reconstruction microscopy, he concluded that the general consensus emerging from experimental studies is that the notion of universally anomalous diffusion in and around cells as a consequence of molecular crowding may not be correct, and that the slowing of diffusion in cells is less marked than has been widely assumed and can be simply described through a five- to sixfold reduction of the normal diffusion coefficient. A Soranno, from the University of Zürich (Switzerland), described how, by employing FRET measurements, it is possible to quantify the effect of molecular crowding on the dimensions of the highly charged, intrinsically disordered protein human prothymosin alpha. For a large variety of polymeric crowders (PEG, PVP, Ficoll, Dextran, PVA, PAA), a collapse of the polypeptide chain is observed with increasing polymer size and polymer concentration. The largest extent of collapse is observed for polymer radii comparable to the dimensions of the protein, in agreement with theoretical considerations. For his contribution, A Soranno was awarded the CSF Award for the best contributed talk. In his most inspiring talk, Clifford Brangwynne, from Princeton University (USA), drew attention to very important objects, namely Ribonucleoprotein (RNP) bodies. These are non-membrane-bound macromolecular assemblies that form from the dynamic interactions of RNA and proteins. The assembly of RNP bodies may sensitively depend on the biophysical features of the surrounding cytoplasm, including the degree of crowding, transport coefficients and mechanical properties. This dependency may have important implications for the RNA processing reactions involved in fundamental biological processes such as developmental cell growth. Remarkably, Brangwynne showed how RNPs behave in the cell as liquid droplets, pointing to a possible entirely new means that the cell could use to control and fine-tune its internal processes, in fact, more than that, a completely unexplored, new state of organization of living matter, and a functional one. Giuseppe Zaccai, from Institut Laue Langevin, Grenoble (France), showed that protein dynamics is more sensitive than structure to environmental factors such as crowding, solvent, temperature or pressure. Furthermore, he convincingly explained how neutron scattering provides unique experimental data to underpin MD calculations in this context. Following up on environment-induced modulations of protein functional dynamics, Ruth Nussinov, from Tel Aviv University (Israel), addressed the important problem of whether cellular signals can travel long distances in a crowded environment. She proposed a model based on the evolution of at least three properties: a modular functional organization of the cellular network, sequences in some key regions of proteins, such as linkers or loops, and compact interactions between proteins, possibly favoured by a crowded environment. The workshop ended on a keynote lecture by Jean-Marie Lehn, from the Université de Strasbourg (France). Lehn, 1987 Nobel Laureate in chemistry, offered a 'supramolecular view' of the field of molecular interactions. Supramolecular chemistry explores the design of systems undergoing self-organization , i.e. systems capable of generating well-defined functional supramolecular architectures by self-assembling from their components, thus behaving as programmed chemical systems . Chemistry may therefore be considered an information science , the science of informed matter. Supramolecular chemistry is intrinsically a dynamic chemistry in view of the ability of the interactions connecting the molecular components of a supramolecular entity and the resulting ability of supramolecular species to exchange their constituents. The same holds for molecular chemistry when the molecular entity contains covalent bonds that may form and break reversibly, so as to allow a continuous change in constitution by the reorganization and exchange of building blocks. These features define a constitutional dynamic chemistry (CDC) on both the molecular and supramolecular levels. CDC takes advantage of dynamic constitutional diversity to allow variation and selection in response to either internal or external factors to achieve adaptation . The merging of the features-information and programmability, dynamics and reversibility, constitution and structural diversity-points towards the emergence of adaptive and evolutive chemistry . The whole workshop could have not taken place without the help of the Centro Stefano Franscini. The CSF is the congress centre of the Swiss Federal Institute of Technology of Zurich (ETH Zurich) and has been situated at Monte Verità since 1989. It is an ideal meeting point for all members of the international scientific community who wish to discuss the state-of-the-art and new challenges of any field of research. The CSF supports 20-25 international conferences every year and, since 2010, up to ten winter doctoral schools1. The competence and professionalism of the staff were at the same level of beauty and inspiring character as that of Monte Verità. A meeting of this sort, if successful, leaves the audience with more open questions than settled answers, and this was definitely the case for Crowding 2012. Excluded volume is clearly a fundamental concept that has allowed crowding, a very familiar concept in soft matter, to enter into the domain of biological sciences. However, the complexity of the biological milieu calls for more refined descriptions. What is the role of electrostatic and electrodynamic interactions? What is the role of hydrodynamics interactions? To what extent does the strong spatial inhomogeneity (clustering of molecules, cellular compartmentalization, etc) have to be taken into account? Or, more generally, what are the minimal elements that prove crucial to describe reactions within a cell? How does the diffusion proceed (diffusion, slow diffusion, sub-diffusion) given that the experimental evidences are still controversial? In conclusion, we knew that allowing scientists with very different backgrounds and ideas to mingle was a hazardous attempt. Despite that, the workshop turned out to be a very successful experiment, which was highly enjoyed both by the participants and the organizers. Discussions sparked regularly among ever-changing groups, comprising senior scientists and students, despite the rather tight schedule, adding to the sense of fulfilment ignited by the outstanding level of the presentations. Given the success of the meeting Crowding 2012, a new event has been organized and will take place on the same themes during fall 2013, this time in the beautiful scenery of the Loire valley in France. The workshop 'Macromolecular crowding effects in cell biology: models and experiments' will be held on the CNRS campus in Orléans, France, on 24-25 October 2013. More information can be found on the workshop website: http://dirac.cnrs-orleans.fr/∼piazza/. 1Source: www.csf.ethz.ch/

6.
J Prev Med Hyg ; 54(4): 212-7, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24779283

RESUMO

INTRODUCTION: A cross-sectional study was undertaken to determine the prevalence of Giardia and Cryptosporidium in calves of Palermo area (Sicily) and to evaluate the occupational risk associated with occurrence of zoonotic genotypes. METHODS: A total of 217 faecal samples, from 149 calves (between 2 and 240 days of age) and 68 farmers, were collected in 19 cattle-farms of Palermo area. A questionnaire regarding demographic characteristics and personal hygienic measures was submitted to all farmers. All faecal samples were analyzed by Immunofluorescence assay and Polimerase Chain Reaction (PCR); genotypes were determined by DNA sequencing of Triose Phosphate Isomerase gene for Giardia and Small Subunit Ribosomal RNA gene for Cryptosporidium. RESULTS: None farmer tested was positive for Giardia and Cryptosporidium, whereas these protozoa were respectively detected in 53 (including 5 with zoonotic G. duodenalis genotype A) and 17 (of which 1 with zoonotic C. ubiquitum) of the examined calves. DISCUSSION: The results indicate that the risk of transmitting both protozoa to farmers in Palermo area is negligible although it cannot be considered null because of identification of human genotypes/species in calves.


Assuntos
Agricultura , Cryptosporidium/isolamento & purificação , Fezes/parasitologia , Giardia/isolamento & purificação , Exposição Ocupacional , Adolescente , Adulto , Animais , Bovinos , Estudos Transversais , Cryptosporidium/genética , Feminino , Giardia/genética , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , RNA de Protozoário/genética , RNA Ribossômico/genética , Análise de Sequência de DNA , Triose-Fosfato Isomerase/genética , Adulto Jovem
7.
Eur Rev Med Pharmacol Sci ; 16(5): 699-700, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22774415

RESUMO

OBJECTIVE: We present an additional very rare case of a congenital tympanic membrane cholesteatoma (CTMC) in the adult. METHOD: Case report and literature review of CTMC. CASE REPORT: A 54-year old man was referred to us by his primary care physician who noted a white mass on the right tympanic membrane without prior history of otorrhea, tympanic perforations or previous otologic procedures. The pearl was about 5 mm diameter, centered on the umbo of a normal tympanic membrane (TM). The audiogram and the tympanogram was absolutely normal. CT confirmed a soft round shape tissue mass, located in the centre of the TM near umbo. The mass protruded both in the auditory canal and in the middle ear space, touching the malleus extremity, without any relationship with medial wall of the cavum tympani. A surgical excision was performed using a "minimal" retroauricolar transcanalar approach: the CTMC was located into the thickness of the TM, between epidermic and mucous layers. The ossicular chain was preserved intact. A partial myringoplasty (underlay technique) using a temporalis fascia graft was necessary. Histopathology confirmed a cystic cholesteatoma. After two months and one year follow-up, otoendoscopy showed a well-healed TM with a preserved normal audiogram and tympanogram. DISCUSSION: This exceptional (probably the first reported) case showed the possible localization of the CC in the TM, also in the adult. Criteria for classification of a TM cholesteatoma as congenital and possible pathogenetic mechanisms are discussed.


Assuntos
Colesteatoma da Orelha Média/congênito , Membrana Timpânica/patologia , Colesteatoma da Orelha Média/diagnóstico , Colesteatoma da Orelha Média/cirurgia , Endoscopia , Humanos , Masculino , Pessoa de Meia-Idade , Miringoplastia , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Membrana Timpânica/diagnóstico por imagem , Membrana Timpânica/cirurgia , Timpanoplastia
8.
J Prev Med Hyg ; 53(4): 181-5, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23469584

RESUMO

INTRODUCTION: In recent years an increase in the number of sexually transmitted infections (STIs) in men who have sex with men (MSM) has been reported in different industrialised countries. Because few epidemiological data on the STls/MSM population in Sicily are available, a survey was conducted to assess the prevalence of STls/enteric protozoa and risky sexual behaviours among MSM in western Sicily. METHODS: In 2010, 74 MSM with median age of 30 years old, were recruited via networks. All participants to the study were interviewed by anonymous self-administered questionnaire in order to collect social/demographic information, clinic data and STI-related risky sexual behaviours. After completing the questionnaire, blood samples were collected to determine HIV, HCV, HHV8 and Treponema pallidum antibodies; presence of Giardia duodenalis and Cryptosporidium parvum was also investigated in faecal samples by immunofluorescence assay. RESULTS: HIV, HHV8, T. pallidum and Giardia prevalence were 8.1%, 16.2%, 21.6% and 16.4% respectively; all patients were negative for HCV and Cryptosporidium infections. The median values of sexual anal intercourse and oral sex per week were 2 and 1, respectively. 7% of participants always had unprotected anal sex, 50.7% sometimes used condom during sexual anal intercourse and 42.3% always had protected anal sex. All MSM-HIV+ and 7 (43.7%) syphilis seropositives were unaware of their own infection. DISCUSSION: MSM in western Sicily are a high risk group for important STIs. It seems necessary that continuous interventions for preventing HIV/AIDS and other STls and for improving the level of knowledge of symptoms are needed.


Assuntos
Homossexualidade Masculina/estatística & dados numéricos , Infecções Sexualmente Transmissíveis/epidemiologia , Sexo sem Proteção/estatística & dados numéricos , Adolescente , Adulto , Fezes/microbiologia , Fezes/parasitologia , Imunofluorescência , HIV-1/isolamento & purificação , HIV-2/isolamento & purificação , Hepacivirus/isolamento & purificação , Herpesvirus Humano 8/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Soroepidemiológicos , Infecções Sexualmente Transmissíveis/microbiologia , Infecções Sexualmente Transmissíveis/parasitologia , Sicília/epidemiologia , Sífilis/epidemiologia , Sífilis/microbiologia , Treponema pallidum/isolamento & purificação , Adulto Jovem
9.
J Laryngol Otol ; 136(3): 268-270, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34666860

RESUMO

OBJECTIVES: To report an extremely rare case of malleoincudal osteoma that led to conductive hearing loss despite an unusually normal otomicroscopic appearance, and to highlight the usefulness of costal cartilage for ossicular chain reconstruction after tumour removal. CASE REPORT: A 37-year-old woman presented with a 2-year history of progressive, right-sided hearing loss. Physical examination revealed a normal tympanic membrane. Pure tone audiometry showed a right-sided conductive hearing loss. High-resolution computed tomography revealed a right-sided epitympanic mass arising from the malleus head and contiguous with the incus. The patient underwent a closed mastoido-epitympanectomy. The malleus head and the incus with associated malleoincudal osteoma were removed. Ossicular chain reconstruction using costal cartilage was performed at the time of tumour removal. CONCLUSION: The possibility of a middle-ear osteoma must be considered in cases of unilateral and progressive conductive hearing loss with a normal otomicroscopic appearance in patients with no history of ear infection, trauma or prior surgery, and with no family history of hearing loss. Surgical treatment is indicated in cases of significant conductive hearing loss. To our knowledge, this is the first case report of malleoincudal osteoma in which the ossicular chain was reconstructed using costal cartilage.


Assuntos
Neoplasias Ósseas/cirurgia , Cartilagem Costal/transplante , Bigorna , Martelo , Substituição Ossicular/métodos , Osteoma/cirurgia , Adulto , Feminino , Humanos
10.
Phys Rev Lett ; 106(2): 025302, 2011 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-21405237

RESUMO

We study the population dynamics of a Bose-Einstein condensate in a double-well potential throughout the crossover from Josephson dynamics to hydrodynamics. At barriers higher than the chemical potential, we observe slow oscillations well described by a Josephson model. In the limit of low barriers, the fundamental frequency agrees with a simple hydrodynamic model, but we also observe a second, higher frequency. A full numerical simulation of the Gross-Pitaevskii equation giving the frequencies and amplitudes of the observed modes between these two limits is compared to the data and is used to understand the origin of the higher mode. Implications for trapped matter-wave interferometers are discussed.

11.
Phys Rev Lett ; 105(12): 120601, 2010 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-20867619

RESUMO

Diffusion-limited reactions are usually described within the Smoluchowski theory, which neglects interparticle interactions. We propose a simple way to incorporate excluded-volume effects building on simulations of hard sphere in the presence of a sink. For large values of the sink-to-particle size ratio R(s), the measured encounter rate is in good agreement with a simple generalization of the Smoluchowski equation at high densities. Reducing R(s), the encounter rate is substantially depressed and becomes even nonmonotonic for R(s)<<1. Concurrently with the saturation of the rate, stationary density waves set in close to the sink. A mean-field analysis helps to shed light on the subtle link between such ordering and the slowing down of the encounter dynamics. Finally, we show how an infinitesimal amount of nonreacting impurities can equally slow down dramatically the reaction.


Assuntos
Simulação de Dinâmica Molecular , Nanopartículas/química , Polímeros/química , Algoritmos , Coloides/química , Difusão , Tamanho da Partícula
12.
Cephalalgia ; 30(2): 233-8, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19438914

RESUMO

The mean age of onset of cluster headache (CH) is in the late third decade. Only few cases of childhood-onset (< 14 years) CH have been reported in the literature. We report the case of an 11-year-old boy who suffered from sudden attacks of shock-like, intense pain, localized in the right orbital region, with associated photophobia, phonophobia, conjunctival injection, lacrimation, nasal congestion, rhinorrhoea and psychomotor agitation. The episodes lasted 60-180 min, and the headache frequency was one to three per day. Physical and neurological examinations, magnetic resonance imaging and blood examinations were normal. The first bout lasted 8 months. Attacks were resistant to every symptomatic and partially to prophylactic treatment that has been tried. The second bout lasted approximately 2 months.


Assuntos
Cefaleia Histamínica/tratamento farmacológico , Cefaleia Histamínica/fisiopatologia , Corticosteroides/uso terapêutico , Analgésicos/uso terapêutico , Criança , Cefaleia Histamínica/complicações , Esotropia/complicações , Esotropia/cirurgia , Humanos , Masculino , Exame Neurológico , Testes Neuropsicológicos , Procedimentos Cirúrgicos Oftalmológicos
13.
Eur Phys J E Soft Matter ; 33(1): 89-96, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20852913

RESUMO

In this paper we analyze the vibrational spectra of a large ensemble of non-homologous protein structures by means of a novel tool, that we coin Hierarchical Network Model (HNM). Our coarse-grained scheme accounts for the intrinsic heterogeneity of force constants displayed by protein arrangements and also incorporates side chain degrees of freedom. Our analysis shows that vibrational entropy per unit residue correlates with the content of secondary structure. Furthermore, we assess the individual contribution to vibrational entropy of the novel features of our scheme as compared with the predictions of state-of-the-art network models. This analysis highlights the importance of properly accounting for the intrinsic hierarchy in force strengths typical of the different atomic bonds that build up and stabilize protein scaffolds. Finally, we discuss possible implications of our findings in the context of protein aggregation phenomena.


Assuntos
Entropia , Proteínas/química , Vibração , Bases de Dados de Proteínas , Modelos Moleculares , Estabilidade Proteica , Estrutura Secundária de Proteína , Análise Espectral
14.
J Neuroimmunol ; 338: 577109, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31715460

RESUMO

Cerebral amyloid angiopathy-related inflammation (CAA-ri) is a rare and treatable variant of CAA likely due to an autoimmune response directed toward beta-amyloid deposits. Cognitive and behavioral manifestations are the most common symptoms, followed by focal neurological signs, headache and seizures, associated with characteristics neuroradiological features on brain magnetic resonance imaging (MRI). We describe the clinical course, radiological features and therapeutic approach of two patients with probable CAA-ri with the aim of emphasizing the importance of an early diagnosis of this potentially reversible disease in different neurological settings, such as memory clinics and stroke units.


Assuntos
Angiopatia Amiloide Cerebral/diagnóstico , Demência Vascular/diagnóstico , Inflamação/diagnóstico , Idoso , Peptídeos beta-Amiloides/imunologia , Autoanticorpos/sangue , Angiopatia Amiloide Cerebral/complicações , Angiopatia Amiloide Cerebral/tratamento farmacológico , Feminino , Humanos , Imunossupressores/uso terapêutico , Inflamação/tratamento farmacológico , Imageamento por Ressonância Magnética , Masculino
15.
Leukemia ; 21(5): 1060-9, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17361229

RESUMO

Using polymerase chain reaction (PCR)-based sequence-specific primers, the killer immunoglobulin-like receptor (KIR) genotypes of 35 patients with natural killer (NK)-type lymphoproliferative disease of granular lymphocytes and of 50 normal subjects were investigated to evaluate whether genes coding for activating KIRs were more frequently detected in patients with NK-lymphoproliferative disease of granular lymphocytes (LDGL). Genotype frequency indicated that the most frequently found gene content was eight genes in controls and 14 in patients (P<0.05). The KIR genotype analysis revealed that patient and, surprisingly, control KIR genotypes preferentially consisted of type B haplotypes characterized by the presence of multiple-activating KIRs. Evidence was also provided that the same KIR genotype was shared by a variable number of patients. Interestingly, the recurrent genotypes observed in the patient group were not found in controls. Concerning inhibitory genes, KIR2DL5a and 2DL5b were more frequently detected in patients than in controls (P<0.01), likely representing a discrete feature of the genetic repertoire of the patients. KIR gene repertoire analysis in patients suggests that the susceptibility to NK-LDGL might be related to the presence of activating KIR genes and supports the concept that these receptors may be involved in the priming of granular lymphocytes (GL) proliferation. Population analysis might disclose a genetic background predisposing to this disease.


Assuntos
Células Matadoras Naturais/patologia , Transtornos Linfoproliferativos/imunologia , Receptores Imunológicos/genética , Adulto , Idoso , Feminino , Frequência do Gene , Genes MHC Classe I , Genótipo , Humanos , Células Matadoras Naturais/imunologia , Transtornos Linfoproliferativos/genética , Transtornos Linfoproliferativos/patologia , Masculino , Pessoa de Meia-Idade , Receptores KIR , Receptores KIR2DL5
17.
Phys Rev E ; 97(2-1): 023301, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29548108

RESUMO

We present an efficient point-particle approach to simulate reaction-diffusion processes of spherical absorbing particles in the diffusion-limited regime, as simple models of cellular uptake. The exact solution for a single absorber is used to calibrate the method, linking the numerical parameters to the physical particle radius and uptake rate. We study the configurations of multiple absorbers of increasing complexity to examine the performance of the method by comparing our simulations with available exact analytical or numerical results. We demonstrate the potential of the method to resolve the complex diffusive interactions, here quantified by the Sherwood number, measuring the uptake rate in terms of that of isolated absorbers. We implement the method in a pseudospectral solver that can be generalized to include fluid motion and fluid-particle interactions. As a test case of the presence of a flow, we consider the uptake rate by a particle in a linear shear flow. Overall, our method represents a powerful and flexible computational tool that can be employed to investigate many complex situations in biology, chemistry, and related sciences.


Assuntos
Células/metabolismo , Modelos Biológicos , Transporte Biológico , Difusão
18.
J Clin Invest ; 104(1): 115-21, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10393705

RESUMO

B- and T-cell recirculation is crucial for the function of the immune system, with the control of cell migration being mainly mediated by several chemokines and their receptors. In this study, we investigated the expression and function of CXCR3 on normal and malignant B cells from 65 patients with chronic lymphoproliferative disorders (CLDs). Although CXCR3 is lacking on CD5(+) and CD5(-) B cells from healthy subjects, it is expressed on leukemic B lymphocytes from all (31/31) patients with chronic lymphocytic leukemia (CLL). The presence of CXCR3 was heterogeneous in other B-cell disorders, being expressed in 2 of 7 patients with mantle cell lymphoma (MCL), 4 of 12 patients with hairy cell leukemia (HCL), and 11 of 15 patients with other subtypes of non-Hodgkin's lymphomas (NHLs). Chemotaxis assay shows that normal B cells from healthy subjects do not migrate in response to IFN-inducible protein 10 (IP-10) and IFN-gamma-induced monokine (Mig). In contrast, a definite migration in response to IP-10 and Mig has been observed in all malignant B cells from patients with CLL, but not in patients with HCL or MCL (1/7 cases tested). Neoplastic B cells from other NHLs showed a heterogenous pattern. The migration elicited by IP-10 and Mig was inhibited by blocking CXCR3. No effect of IP-10 and Mig chemokines was observed on the cytosolic calcium concentration in malignant B cells. The data reported here demonstrate that CXCR3 is expressed on malignant B cells from CLDs, particularly in patients with CLL, and represents a fully functional receptor involved in chemotaxis of malignant B lymphocytes.


Assuntos
Linfócitos B/fisiologia , Quimiotaxia de Leucócito/fisiologia , Leucemia de Células Pilosas/patologia , Linfoma de Células B/patologia , Proteínas de Neoplasias/fisiologia , Células-Tronco Neoplásicas/fisiologia , Receptores de Quimiocinas/fisiologia , Adulto , Idoso , Linfócitos B/química , Cálcio/metabolismo , Quimiocina CXCL10 , Quimiocinas CXC/farmacologia , Quimiotaxia de Leucócito/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Interferon gama/farmacologia , Leucemia de Células Pilosas/metabolismo , Linfoma de Células B/metabolismo , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Células-Tronco Neoplásicas/química , Receptores CXCR3 , Receptores de Quimiocinas/biossíntese , Receptores de Quimiocinas/genética
19.
Ann Ig ; 19(5): 473-81, 2007.
Artigo em Italiano | MEDLINE | ID: mdl-18210777

RESUMO

The knowledge, attitude, and practice toward the use of ready-to-eat vegetables were evaluated in a sample of 701 (388 women and 313 men) potential consumers in Palermo, by answering to an anonymous questionnaire handed out. Food safety perceptions and behaviors were analysed; in general, interviewed consumers who perceived higher risks exhibited safer food behaviors. There weren't considerable differences in the use of these salads between two sexes; 81.4% of respondents uses these products to save a lot of time, particularly the graduates attach importance to saving in time (p = 0.001), and only 34.4% is worrying about high price. Statistical analysis showed a significant correlation between better food safety knowledge and female sex; for example, compared with women, men reported to buy ready-to-eat salads on sale at room temperature and at temperature of refrigerator without distinction (p = 0.015). This study confirms the IV range salads meet modern consumer's requirements and also suggests the need of food safety educational strategies for targeted groups.


Assuntos
Qualidade de Produtos para o Consumidor , Manipulação de Alimentos , Conhecimentos, Atitudes e Prática em Saúde , Verduras , Adolescente , Adulto , Interpretação Estatística de Dados , Inquéritos sobre Dietas , Feminino , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Inquéritos e Questionários
20.
Leukemia ; 31(2): 292-300, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27479180

RESUMO

Protein kinase CK2 sustains acute myeloid leukemia cell growth, but its role in leukemia stem cells is largely unknown. Here, we discovered that the CK2 catalytic α and regulatory ß subunits are consistently expressed in leukemia stem cells isolated from acute myeloid leukemia patients and cell lines. CK2 inactivation with the selective inhibitor CX-4945 or RNA interference induced an accumulation of leukemia stem cells in the late S-G2-M phases of the cell cycle and triggered late-onset apoptosis. As a result, leukemia stem cells displayed an increased sensitivity to the chemotherapeutic agent doxorubicin. From a molecular standpoint, CK2 blockade was associated with a downmodulation of the stem cell-regulating protein BMI-1 and a marked impairment of AKT, nuclear factor-κB (NF-κB) and signal transducer and activator of transcription 3 (STAT3) activation, whereas FOXO3a nuclear activity was induced. Notably, combined CK2 and either NF-κB or STAT3 inhibition resulted in a superior cytotoxic effect on leukemia stem cells. This study suggests that CK2 blockade could be a rational approach to minimize the persistence of residual leukemia cells.


Assuntos
Caseína Quinase II/metabolismo , Leucemia Mieloide Aguda/metabolismo , NF-kappa B/metabolismo , Células-Tronco Neoplásicas/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator de Transcrição STAT3/metabolismo , Trifosfato de Adenosina/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/farmacologia , Biomarcadores , Caseína Quinase II/antagonistas & inibidores , Caseína Quinase II/genética , Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Proteína Forkhead Box O3/genética , Proteína Forkhead Box O3/metabolismo , Expressão Gênica , Humanos , Imunofenotipagem , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Masculino , Pessoa de Meia-Idade , Complexo Repressor Polycomb 1/genética , Complexo Repressor Polycomb 1/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Transdução de Sinais
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA