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The central idea of this review is to consider quantum field theory models relevant for particle physics and replace the fermionic matter in these models by a bosonic one. This is mostly motivated by the fact that bosons are more 'accessible' and easier to manipulate for experimentalists, but this 'substitution' also leads to new physics and novel phenomena. It allows us to gain new information about among other things confinement and the dynamics of the deconfinement transition. We will thus consider bosons in dynamical lattices corresponding to the bosonic Schwinger or [Formula: see text] Bose-Hubbard models. Another central idea of this review concerns atomic simulators of paradigmatic models of particle physics theory such as the Creutz-Hubbard ladder, or Gross-Neveu-Wilson and Wilson-Hubbard models. This article is not a general review of the rapidly growing field-it reviews activities related to quantum simulations for lattice field theories performed by the Quantum Optics Theory group at ICFO and their collaborators from 19 institutions all over the world. Finally, we will briefly describe our efforts to design experimentally friendly simulators of these and other models relevant for particle physics. This article is part of the theme issue 'Quantum technologies in particle physics'.
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We demonstrate Floquet engineering in a basic yet scalable 2D architecture of individually trapped and controlled ions. Local parametric modulations of detuned trapping potentials steer the strength of long-range interion couplings and the related Peierls phase of the motional state. In our proof of principle, we initialize large coherent states and tune modulation parameters to control trajectories, directions, and interferences of the phonon flow. Our findings open a new pathway for future Floquet-based trapped-ion quantum simulators targeting correlated topological phenomena and dynamical gauge fields.
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We introduce a model of quantum magnetism induced by the nonperturbative exchange of microwave photons between distant superconducting qubits. By interconnecting qubits and cavities, we obtain a spin-boson lattice model that exhibits a quantum phase transition where both qubits and cavities spontaneously polarize. We present a many-body ansatz that captures this phenomenon all the way, from a the perturbative dispersive regime where photons can be traced out, to the nonperturbative ultrastrong coupling regime where photons must be treated on the same footing as qubits. Our ansatz also reproduces the low-energy excitations, which are described by hybridized spin-photon quasiparticles, and can be probed spectroscopically from transmission experiments in circuit QED, as shown by simulating a possible experiment by matrix-product-state methods.
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The vibrations of a collection of ions in a microtrap array can be described in terms of tunneling phonons. We show that the vibrational couplings may be tailored by using a gradient of the trap frequencies together with a periodic driving of the trapping potentials. These ingredients allow us to induce effective gauge fields on the vibrational excitations, such that phonons mimic the behavior of charged particles in a magnetic field. In particular, microtrap arrays are well suited to realize a quantum simulator of the famous Aharonov-Bohm effect and observe the paradigmatic edge states typical from quantum-Hall samples and topological insulators.
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Due to their pluripotent nature and unlimited cell renewal, stem cells have been proposed as an ideal material for establishing long-term cnidarian cell cultures. However, the lack of unifying principles associated with "stemness" across the phylum complicates stem cells' identification and isolation. Here, we for the first time report gene expression profiles for cultured coral cells, focusing on regulatory gene networks underlying pluripotency and differentiation. Cultures were initiated from Acropora digitifera tip fragments, the fastest growing tissue in Acropora. Overall, in vitro transcription resembled early larvae, overexpressing orthologs of premetazoan and Hydra stem cell markers, and transcripts with roles in cell division, migration, and differentiation. Our results suggest the presence of pluripotent cell types in cultures and indicate the existence of ancestral genome regulatory modules underlying pluripotency and cell differentiation in cnidaria. Cultured cells appear to be synthesizing protein, differentiating, and proliferating.
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Antozoários/citologia , Antozoários/genética , Animais , Diferenciação Celular , Divisão Celular , Células Cultivadas , Redes Reguladoras de Genes , TranscriptomaRESUMO
BACKGROUND: The coral skeleton consists of CaCO3 deposited upon an organic matrix primarily as aragonite. Currently galaxin, from Galaxea fascicularis, is the only soluble protein component of the organic matrix that has been characterized from a coral. Three genes related to galaxin were identified in the coral Acropora millepora. RESULTS: One of the Acropora genes (Amgalaxin) encodes a clear galaxin ortholog, while the others (Amgalaxin-like 1 and Amgalaxin-like 2) encode larger and more divergent proteins. All three proteins are predicted to be extracellular and share common structural features, most notably the presence of repetitive motifs containing dicysteine residues. In situ hybridization reveals distinct, but partially overlapping, spatial expression of the genes in patterns consistent with distinct roles in calcification. Both of the Amgalaxin-like genes are expressed exclusively in the early stages of calcification, while Amgalaxin continues to be expressed in the adult, consistent with the situation in the coral Galaxea. CONCLUSION: Comparisons with molluscs suggest functional convergence in the two groups; lustrin A/pearlin proteins may be the mollusc counterparts of galaxin, whereas the galaxin-like proteins combine characteristics of two distinct proteins involved in mollusc calcification. Database searches indicate that, although sequences with high similarity to the galaxins are restricted to the Scleractinia, more divergent members of this protein family are present in other cnidarians and some other metazoans. We suggest that ancestral galaxins may have been secondarily recruited to roles in calcification in the Triassic, when the Scleractinia first appeared. Understanding the evolution of the broader galaxin family will require wider sampling and expression analysis in a range of cnidarians and other animals.
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Antozoários/genética , Calcificação Fisiológica/genética , Metamorfose Biológica/genética , Sequência de Aminoácidos , Animais , Antozoários/metabolismo , Etiquetas de Sequências Expressas , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Dados de Sequência Molecular , Proteínas/genética , Proteínas/metabolismo , Alinhamento de Sequência , Análise de Sequência de DNARESUMO
The dual role played by symmetry in many-body physics manifests itself through two fundamental mechanisms: spontaneous symmetry breaking and topological symmetry protection. These two concepts, ubiquitous in both condensed matter and high energy physics, have been applied successfully in the last decades to unravel a plethora of complex phenomena. Their interplay, however, remains largely unexplored. Here we report how, in the presence of strong correlations, symmetry protection emerges from a set of configurations enforced by another broken symmetry. This mechanism spawns different intertwined topological phases, where topological properties coexist with long-range order. Such a singular interplay gives rise to interesting static and dynamical effects, including interaction-induced topological phase transitions constrained by symmetry breaking, as well as a self-adjusted fractional pumping. This work paves the way for further exploration of exotic topological features in strongly-correlated quantum systems.
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Members of the Alphapapillomavirus genus are causative agents for cervix cancer and benign lesions in humans. These viruses are classified according to sequence similarities in their L1 region. Yet, viral carcinogenicity has been associated with variations in the proteins encoded by the E6 and E7 genes. In order to relate evolutionary history with origin of carcinogenicity, we performed phylogenetic reconstructions using both nucleotide and predicted amino acid sequences of the L1, E6 and E7 genes. Whilst phylogenetic analysis of L1 reconstructed genus evolutionary history, phylogenies based on E6 and E7 proteins support the idea that mutations at amino acids S/Tx [V/L] (E6) and LxCxE (E7) might be responsible for carcinogenic potential. These findings indicate that virulence within Alphapapillomavirus have appeared multiple times during evolution. Our results reveal that oncogenic potential is not a monophyletic clade-specific adaptation but might be the result of positive selection on random mutations occurring on proteins involved in host infection during viral diversification.
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Alphapapillomavirus/classificação , Alphapapillomavirus/genética , Transformação Celular Viral , Evolução Molecular , Proteínas Oncogênicas Virais/genética , Proteínas E7 de Papillomavirus/genética , Filogenia , Tropismo Viral , Sequência de Aminoácidos , Sequência de Bases , Biologia Computacional/métodos , Sequência Conservada , Feminino , Genótipo , Humanos , Mutação , Proteínas Oncogênicas Virais/química , Proteínas E7 de Papillomavirus/química , Neoplasias do Colo do Útero/etiologiaRESUMO
Corals belong to the most basal class of the Phylum Cnidaria, which is considered the sister group of bilaterian animals, and thus have become an emerging model to study the evolution of developmental mechanisms. Although cell renewal, differentiation, and maintenance of pluripotency are cellular events shared by multicellular animals, the cellular basis of these fundamental biological processes are still poorly understood. To understand how changes in gene expression regulate morphogenetic transitions at the base of the eumetazoa, we performed quantitative RNA-seq analysis duringAcropora digitifera's development. We collected embryonic, larval, and adult samples to characterize stage-specific transcription profiles, as well as broad expression patterns. Transcription profiles reconstructed development revealing two main expression clusters. The first cluster grouped blastula and gastrula and the second grouped subsequent developmental time points. Consistently, we observed clear differences in gene expression between early and late developmental transitions, with higher numbers of differentially expressed genes and fold changes around gastrulation. Furthermore, we identified three coexpression clusters that represented discrete gene expression patterns. During early transitions, transcriptional networks seemed to regulate cellular fate and morphogenesis of the larval body. In late transitions, these networks seemed to play important roles preparing planulae for switch in lifestyle and regulation of adult processes. Although developmental progression inA. digitiferais regulated to some extent by differential coexpression of well-defined gene networks, stage-specific transcription profiles appear to be independent entities. While negative regulation of transcription is predominant in early development, cell differentiation was upregulated in larval and adult stages.
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Antozoários/genética , Redes Reguladoras de Genes/genética , Larva/genética , Transcriptoma/genética , Animais , Antozoários/crescimento & desenvolvimento , Diferenciação Celular/genética , Evolução Molecular , Regulação da Expressão Gênica no Desenvolvimento , Larva/crescimento & desenvolvimentoRESUMO
The objective of this study was to review the evidence on the use of opioids for treatment of the dyspnea in adult cancer patients. A systematic literature review was conducted in the databases MEDLINE, CINAHL (EBSCO), ScienceDirect, and Cochrane Library of trials testing the effect of opioids in relieving dyspnea in cancer patients. Fourteen trials met the criteria for inclusion in the review. Eight randomized trials and six nonrandomized trials. All randomized clinical trials analyzed present risks of bias. Morphine has been the most studied strong opioid showing efficacy in alleviating dyspnea when administered, either orally or subcutaneously, in cancer patients. The potential benefit of the strong opioids in the alleviation of dyspnea in cancer patients is modest and limited to some opioids. More studies are needed to sufficiently support the role of opioids in dyspnea at rest, at exertion, and for breakthrough dyspnea and to clarify the safety issues.
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Analgésicos Opioides/uso terapêutico , Dispneia/complicações , Dispneia/tratamento farmacológico , Neoplasias/complicações , Neoplasias/tratamento farmacológico , Analgésicos Opioides/administração & dosagem , Analgésicos Opioides/efeitos adversos , Benzodiazepinas/administração & dosagem , Benzodiazepinas/uso terapêutico , Quimioterapia Combinada , Humanos , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
Resumen Objetivo: Determinar la validez del Índice de Pronóstico de Supervivencia (PapScore) en los pacientes oncológicos referidos al Centro Nacional de Control del Dolor y Cuidados Paliativos de Costa Rica. Métodos: Estudio descriptivo, observacional y prospectivo de los pacientes oncológicos referidos por primera vez al Centro Nacional de Control del Dolor y Cuidados Paliativos durante los meses de mayo y junio del 2015. Se aplicó el índice de pronóstico PaP Score. La base de datos fue realizada en Excel y el análisis estadístico en el programa SPSS. Resultados: Se estudiaron 100 pacientes, el 54% de sexo masculino, con una edad promedio 67,1 años. El cáncer gástrico fue la patología más prevalente con 12% de los casos. El 23% de pacientes presentan disnea, 56% anorexia. A la mayoría de pacientes (67%) se le realizó una estimación clínica mayor a 12 semanas. Un 83% fueron clasificados en el grupo A, 17% en el grupo B y ningún paciente en el grupo C. Analizando la clasificación de riesgo como un test diagnóstico para predecir mortalidad a un mes, muestra un sensibilidad del 61,9%, especificidad del 94,9%, con valor predictivo positivo 76,5% y valor predictivo negativo 90,4%. Conclusión: La escala de PaP Score o Índice Pronóstico de Supervivencia es un instrumento que se adapta a las posibilidades de nuestro entorno nacional. Es una excelente herramienta como predictor de sobrevida a un mes, independientemente del tipo de tumor, con alta eficacia y validez pronóstica.
Abstract Objective: To determine the validity of the Palliative Prognosis Index (PapScore) in cancer patients referred to the National Center for Pain Control and Palliative Care of Costa Rica. Methods: Descriptive, observational and prospective study of oncological patients referred for the first time to the National Center of Pain Control and Palliative Care during the months of May and June 2015. The PaP Score was used. The database was made in Excel and the statistical analysis in the SPSS program. Results: 100 patients were studied, 54% male, with an average age of 67.1 years. Gastric cancer was the most prevalent pathology with 12% of cases, 23% of patients present dyspnea, 56% anorexia. The majority of patients (67%) underwent a clinical prognosis of more than 12 weeks, 83% were classified in group A, 17% in group B and no patient in group C. Analyzing the risk classification as a diagnostic test to predict mortality at one month, shows a sensitivity of 61.9%, specificity 94.9%, with positive predictive value 76.5% and negative predictive value 90.4%. Conclusion: The PaP Score or Palliative Prognosis Index scale is an instrument that adapts to the possibilities of our national environment. It is an excellent tool as a predictor of survival at one month, regardless of the type of tumor, with high efficacy and prognostic validity.
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Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Cuidados Paliativos , Análise de Sobrevida , Neoplasias/mortalidade , Costa Rica , Neoplasias/epidemiologiaRESUMO
To understand the calcium-mediated signalling pathways underlying settlement and metamorphosis in the Scleractinian coral Acropora millepora, a predicted protein set derived from larval cDNAs was scanned for the presence of EF-hand domains (Pfam Id: PF00036). This approach led to the identification of a canonical calmodulin (AmCaM) protein and an uncharacterised member of the Neuronal Calcium Sensor (NCS) family of proteins known here as Acrocalcin (AmAC). While AmCaM transcripts were present throughout development, AmAC transcripts were not detected prior to gastrulation, after which relatively constant mRNA levels were detected until metamorphosis and settlement. The AmAC protein contains an internal CaM-binding site and was shown to interact in vitro with AmCaM. These results are consistent with the idea that AmAC is a target of AmCaM in vivo, suggesting that this interaction may regulate calcium-dependent processes during the development of Acropora millepora.
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Antozoários/crescimento & desenvolvimento , Cálcio/metabolismo , Calmodulina/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Larva/metabolismo , Metamorfose Biológica , Proteínas Sensoras de Cálcio Neuronal/metabolismo , Sequência de Aminoácidos , Animais , Antozoários/genética , Northern Blotting , Calmodulina/genética , Cromatografia de Afinidade , DNA Complementar/genética , Perfilação da Expressão Gênica , Hibridização In Situ , Larva/citologia , Larva/genética , Dados de Sequência Molecular , Proteínas Sensoras de Cálcio Neuronal/genética , Ligação Proteica , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência de AminoácidosAssuntos
Educação Médica/organização & administração , Medicina Interna/educação , Internato e Residência/organização & administração , Cuidados Paliativos/métodos , Medicina Paliativa/educação , Sistemas Automatizados de Assistência Junto ao Leito , Ultrassonografia , Adulto , Idoso , Idoso de 80 Anos ou mais , Competência Clínica , Costa Rica , Currículo , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Objetivo: evaluar el conocimiento de un grupo de médicos residentes del programa de especialidades médicas sobre las pautas de la Organización Mundial de la Salud para el tratamiento del dolor en los pacientes con cáncer. Métodos: para la recolección de los datos se utilizó un cuestionario anónimo y auto administrado. El mismo constaba de 18 preguntas, bajo la modalidad de preguntas abiertas y cerradas; el cual fue aplicado a 70 médicos residentes de ciertas especialidades del programa de especialidades médicas del Centro de Desarrollo Estrátegico e Información en Salud y Seguridad Social que se encontraban en formación en el Hospital Rafael Angel Calderón Guardia...
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Humanos , Masculino , Adulto , Feminino , Analgésicos , Analgésicos Opioides , Educação de Pós-Graduação , Educação de Graduação em Medicina , Oncologia , Neoplasias , Dor , Costa RicaRESUMO
The amount of genomic sequence information continues to grow at an exponential rate, while the identification and characterization of genes without known homologs remains a major challenge. For non-model organisms with limited resources for manipulative studies, high-throughput transcriptomic data combined with bioinformatics methods provide a powerful approach to obtain initial insights into the function of unknown genes. In this study, we report the identification and characterization of a novel family of putatively secreted, small, cysteine-rich proteins herein named Small Cysteine-Rich Proteins (SCRiPs). Their discovery in expressed sequence tag (EST) libraries from the coral Montastraea faveolata required the performance of an iterative search strategy based on BLAST and Hidden-Markov-Model algorithms. While a discernible homolog could neither be identified in the genome of the sea anemone Nematostella vectensis, nor in a large EST dataset from the symbiotic sea anemone Aiptasia pallida, we identified SCRiP sequences in multiple scleractinian coral species. Therefore, we postulate that this gene family is an example of lineage-specific gene expansion in reef-building corals. Previously published gene expression microarray data suggest that a sub-group of SCRiPs is highly responsive to thermal stress. Furthermore, data from microarray experiments investigating developmental gene expression in the coral Acropora millepora suggest that different SCRiPs may play distinct roles in the development of corals. The function of these proteins remains to be elucidated, but our results from in silico, transcriptomic, and phylogenetic analyses provide initial insights into the evolution of SCRiPs, a novel, taxonomically restricted gene family that may be responsible for a lineage-specific trait in scleractinian corals.
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Antozoários/genética , Proteínas/genética , Adaptação Fisiológica/genética , Animais , Antozoários/fisiologia , Cisteína/genética , Etiquetas de Sequências Expressas , Expressão Gênica , Temperatura Alta , Análise de Sequência com Séries de Oligonucleotídeos , Filogenia , Estresse Fisiológico/genéticaRESUMO
Similar to many marine invertebrates, scleractinian corals experience a dramatic morphological transformation, as well as a habitat switch, upon settlement and metamorphosis. At this time, planula larvae transform from non-calcifying, demersal, motile organisms into sessile, calcifying, benthic juvenile polyps. We performed gene expression microarray analyses between planulae, aposymbiotic primary polyps, and symbiotic adult tissue to elucidate the molecular mechanisms underlying coral metamorphosis and early stages of calcification in the Robust/Short clade scleractinian coral Montastraea faveolata. Among the annotated genes, the most abundant upregulated transcripts in the planula stage are involved in protein synthesis, chromatin assembly and mitochondrial metabolism; the polyp stage, morphogenesis, protein catabolism and organic matrix synthesis; and the adult stage, sexual reproduction, stress response and symbiosis. We also present evidence showing that the planula and adult transcriptomes are more similar to each other than to the polyp transcriptome. Our results also point to a large number of uncharacterized adult coral-specific genes likely involved in coral-specific functions such as symbiosis and calcification.
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Objetivo: Revisar las característica de las artroplastías de cadera, parciales o totales, realizadas en el Hospital Nacional Guillermo Almenara-IPSS, Lima-Perú, entre 1995 y 1997. Métodos: Estudio descriptivo, transversal, observacional y prospectivo parcial, en el cual se revisaron 232 historias clínicas de las 325 intervenciones realizadas. Resultados: El grupo etario estuvo entre 59 a 70 años, con predominio del género femenino (60 por ciento), en su mayoría amas de casa y cesantes de Lima Metropolitana. La coxoartrosis fue la etiología más común para la realización de artroplastía total, y la fractura de cuello de fémur para la artroplastía parcial. La complicación más frecuente, a corto plazo, fue la infección de herida operatoria, siendo el S. epidermidis el principal patógeno, y a largo plazo, la luxación de la prótesis. La mortalidad como causa directa es rara, y está asociada a condiciones propias del paciente. El tipo de artroplastía más frecuente fue la total (81 por ciento), con una hospitalización promedio de 29d. Las estancias posoperatorias fueron 15d para la artroplastía parcial y 18d para la total.
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Artroplastia , Prótese de Quadril , Complicações Pós-OperatóriasRESUMO
Objetivo: conocer la distribución y algunas características de las neoplasias malignas del aparato digestivo en una población del Callao -Perú. Diseño: estudio descriptivo, retrospectivo, observacional. Contexto: servicio de Gastroenterología del Hospital Daniel A. Carrión. Participantes: fueron incluidos en el estudio todos los pacientes con diagnóstico de cáncer del aparato digestivo entre noviembre de 1991 y marzo de 1995. Se tomaron como casos todos los pacientes con diagnósticos de neoplasia maligna del aparato digestivo confirmado mediante estudio anatomopatológico, y considerándose positivo el cáncer de páncreas con una eco-tomografía (positivo) y PCRE sugerente de diagnóstico. Intervenciones: se revisaron los informes de endoscopías, colonosigmoidoscopías, laparoscopías, historias clínicas y PCRE, atendidos en el mismo hospital entre noviembre de 1991 y marzo de 1994. Resultados: se encontró 252 casos de cáncer del aparato digestivo, con 63,1 por ciento en varones. La neoplasia más común en 9,1 por ciento. El 12 por ciento de cánceres gástricos se encontraron en menores de 45 años y solo el 22 por ciento se encontró limitado al antro. El 80 por ciento de los cánceres colorrectales se encontraron en colon descendente, sigmoides y recto. El cáncer de ampolla duodenal es encontrado 1,8 veces más frecuentemente que el de páncreas. Conclusiones: el cáncer digestivo es máas común en varones, siendo localización más frecuente en el estómago. 12 por ciento de cánceres gástricos se observan en menores de 45 años . El 80 por ciento de neoplasias de colon son abordables por la proctosigmoidoscopía, además el cáncer de ampolla es la neoplasia periampular más frecuente.