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1.
Nature ; 594(7863): 365-368, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34135524

RESUMO

Red supergiants are the most common final evolutionary stage of stars that have initial masses between 8 and 35 times that of the Sun1. During this stage, which lasts roughly 100,000 years1, red supergiants experience substantial mass loss. However, the mechanism for this mass loss is unknown2. Mass loss may affect the evolutionary path, collapse and future supernova light curve3 of a red supergiant, and its ultimate fate as either a neutron star or a black hole4. From November 2019 to March 2020, Betelgeuse-the second-closest red supergiant to Earth (roughly 220 parsecs, or 724 light years, away)5,6-experienced a historic dimming of its visible brightness. Usually having an apparent magnitude between 0.1 and 1.0, its visual brightness decreased to 1.614 ± 0.008 magnitudes around 7-13 February 20207-an event referred to as Betelgeuse's Great Dimming. Here we report high-angular-resolution observations showing that the southern hemisphere of Betelgeuse was ten times darker than usual in the visible spectrum during its Great Dimming. Observations and modelling support a scenario in which a dust clump formed recently in the vicinity of the star, owing to a local temperature decrease in a cool patch that appeared on the photosphere. The directly imaged brightness variations of Betelgeuse evolved on a timescale of weeks. Our findings suggest that a component of mass loss from red supergiants8 is inhomogeneous, linked to a very contrasted and rapidly changing photosphere.

2.
Chaos ; 34(5)2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38717412

RESUMO

We consider bipartite tight-binding graphs composed by N nodes split into two sets of equal size: one set containing nodes with on-site loss, the other set having nodes with on-site gain. The nodes are connected randomly with probability p. Specifically, we measure the connectivity between the two sets with the parameter α, which is the ratio of current adjacent pairs over the total number of possible adjacent pairs between the sets. For general undirected-graph setups, the non-Hermitian Hamiltonian H(γ,α,N) of this model presents pseudo-Hermiticity, where γ is the loss/gain strength. However, we show that for a given graph setup H(γ,α,N) becomes PT-symmetric. In both scenarios (pseudo-Hermiticity and PT-symmetric), depending on the parameter combination, the spectra of H(γ,α,N) can be real even when it is non-Hermitian. Then we demonstrate, for both setups, that there is a well-defined sector of the γα-plane (which grows with N) where the spectrum of H(γ,α,N) is predominantly real.

3.
Psychol Med ; 53(9): 4266-4274, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-35534479

RESUMO

BACKGROUND: Patients with anti-N-methyl-d-aspartate (NMDA) receptor encephalitis (ANMDARE) show a wide range of behavioral abnormalities and are often mistaken for primary psychiatric presentations. We aimed to determine the behavioral hallmarks of ANMDARE with the use of systematic neuropsychiatric and cognitive assessments. METHODS: A prospective study was conducted, with 160 patients admitted to the National Institute of Neurology and Neurosurgery of Mexico, who fulfilled criteria for possible autoimmune encephalitis and/or red flags along a time window of seven years. Cerebrospinal fluid (CSF) antibodies against the NR1 subunit of the NMDAR were processed with rat brain immunohistochemistry and cell-based assays with NMDA expressing cells. Systematic cognitive, neuropsychiatric, and functional assessments were conducted before knowing NMDAR antibodies results. A multivariate analysis was used to compare patients with and without definite ANMDARE according to antibodies in CSF. RESULTS: After obtaining the CSF antibodies results in 160 consecutive cases, 100 patients were positive and classified as having definite ANMDARE. The most frequent neuropsychiatric patterns were psychosis (81%), delirium (75%), catatonia (69%), anxiety-depression (65%), and mania (27%). Cognition was significantly impaired. A total of 34% of the patients had a predominantly neuropsychiatric presentation without seizures. After multivariate analysis, the clinical hallmarks of ANMDARE consisted of a catatonia-delirium comorbidity, tonic-clonic seizures, and orolingual dyskinesia. CONCLUSIONS: Our study supports the notion of a neurobehavioral phenotype of ANMDARE characterized by a fluctuating course with psychotic and affective symptoms, catatonic signs, and global cognitive dysfunction, often accompanied by seizures and dyskinesia. The catatonia-delirium comorbidity could be a distinctive neurobehavioral phenotype of ANMDARE.


Assuntos
Encefalite Antirreceptor de N-Metil-D-Aspartato , Catatonia , Delírio , Discinesias , Humanos , Encefalite Antirreceptor de N-Metil-D-Aspartato/diagnóstico , Encefalite Antirreceptor de N-Metil-D-Aspartato/líquido cefalorraquidiano , Catatonia/etiologia , Estudos Prospectivos , N-Metilaspartato , Receptores de N-Metil-D-Aspartato , Convulsões/complicações , Delírio/complicações , Discinesias/complicações
4.
Entropy (Basel) ; 25(2)2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36832556

RESUMO

We study the mechanism of scarring of eigenstates in rectangular billiards with slightly corrugated surfaces and show that it is very different from that known in Sinai and Bunimovich billiards. We demonstrate that there are two sets of scar states. One set is related to the bouncing ball trajectories in the configuration space of the corresponding classical billiard. A second set of scar-like states emerges in the momentum space, which originated from the plane-wave states of the unperturbed flat billiard. In the case of billiards with one rough surface, the numerical data demonstrate the repulsion of eigenstates from this surface. When two horizontal rough surfaces are considered, the repulsion effect is either enhanced or canceled depending on whether the rough profiles are symmetric or antisymmetric. The effect of repulsion is quite strong and influences the structure of all eigenstates, indicating that the symmetric properties of the rough profiles are important for the problem of scattering of electromagnetic (or electron) waves through quasi-one-dimensional waveguides. Our approach is based on the reduction of the model of one particle in the billiard with corrugated surfaces to a model of two artificial particles in the billiard with flat surfaces, however, with an effective interaction between these particles. As a result, the analysis is conducted in terms of a two-particle basis, and the roughness of the billiard boundaries is absorbed by a quite complicated potential.

5.
BMC Oral Health ; 22(1): 656, 2022 12 30.
Artigo em Inglês | MEDLINE | ID: mdl-36585679

RESUMO

BACKGROUND: Cerebral palsy (CP) is a non-progressive neuromuscular condition diagnosed in childhood. CP as a form of disability, does not cause any specific oral disease. However, some oral conditions are more commonly associated with people with CP compared to the general population. The overarching aim of the current study was to determine the oral hygiene status, gingival status, and the prevalence of dental caries in children with CP attending a leading hospital institution for children with disabilities in Kampala, Uganda. Additionally, we determined the barriers faced by children with CP in accessing oral healthcare. METHODS: This cross-sectional study was carried out at the Comprehensive Rehabilitation Services Uganda hospital in Kampala, Uganda. Our study population consisted of a convenient sample of 90 children diagnosed with CP aged 3-17 years and their caregivers. A validated and interviewer administered structured questionnaire was used to collect socio-demographic data of the participants. A modified World Health Organization oral health assessment form for those aged 3-17 years was used to gather data on oral health status (plaque score, gingival bleeding and dental caries.) The data was subjected to statistical tests with critical value set up at 5%. RESULTS: Only 32.2% of the children evaluated had adequate oral hygiene, while 44.4% of the children experienced gingival bleeding. The prevalence of dental caries for both deciduous and permanent dentition was 63.3%, with DMFT values of 3.8 ± 4.5. The most common barrier reported by the caregivers was the challenge in modality of transportation availability from the children's homes to the health facilities (34.4%). CONCLUSIONS: Children with CP in the study population have a significant prevalence of oral diseases and face several barriers to oral healthcare. Results from this study aim to provide relevant support to advocate for a nationwide change in policy to improve access to dental care to decrease the burden of oral diseases in children with special healthcare needs.


Assuntos
Paralisia Cerebral , Cárie Dentária , Humanos , Criança , Saúde Bucal , Cárie Dentária/epidemiologia , Paralisia Cerebral/complicações , Paralisia Cerebral/epidemiologia , Uganda/epidemiologia , Estudos Transversais , Atenção à Saúde , Instalações de Saúde , Prevalência
6.
Phys Rev Lett ; 126(15): 153201, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33929231

RESUMO

Overcoming the detrimental effect of disorder at the nanoscale is very hard since disorder induces localization and an exponential suppression of transport efficiency. Here we unveil novel and robust quantum transport regimes achievable in nanosystems by exploiting long-range hopping. We demonstrate that in a 1D disordered nanostructure in the presence of long-range hopping, transport efficiency, after decreasing exponentially with disorder at first, is then enhanced by disorder [disorder-enhanced transport (DET) regime] until, counterintuitively, it reaches a disorder-independent transport (DIT) regime, persisting over several orders of disorder magnitude in realistic systems. To enlighten the relevance of our results, we demonstrate that an ensemble of emitters in a cavity can be described by an effective long-range Hamiltonian. The specific case of a disordered molecular wire placed in an optical cavity is discussed, showing that the DIT and DET regimes can be reached with state-of-the-art experimental setups.

7.
Neurocase ; 27(1): 64-71, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33390066

RESUMO

Cotard syndrome is a clinical condition defined by the presence of nihilistic delusions. We report two patients with Cotard syndrome in whom anti-NMDAR encephalitis (ANMDARE) was confirmed. Both cases showed features of affective psychosis, developed catatonic syndrome, and worsened after the use of antipsychotics. 18F-FDG PET brain studies showed a bilateral hemispheric pattern of hypometabolism in posterior regions, mainly in the cingulate cortex and in the medial aspects of parietal and occipital lobes. A more severe hypometabolism was observed in the right hemisphere of both patients. Both cases remitted with the use of specific immunotherapy for ANMDARE.


Assuntos
Encefalite Antirreceptor de N-Metil-D-Aspartato , Encefalite Antirreceptor de N-Metil-D-Aspartato/complicações , Encefalite Antirreceptor de N-Metil-D-Aspartato/diagnóstico por imagem , Delusões , Fluordesoxiglucose F18 , Humanos , Imagem Molecular , Tomografia por Emissão de Pósitrons
8.
Clin Radiol ; 76(4): 287-293, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33549300

RESUMO

AIM: To examine the frequency and predictive factors for bowel incarceration following transjugular intrahepatic portosystemic shunts (TIPS) placement to treat refractory cirrhosis-induced ascites. MATERIALS AND METHODS: Ninety-nine patients with known hernias at the time of TIPS placement were identified. Their electronic medical records were reviewed and pertinent pre-procedural, procedural, and outcome variables were recorded. Patients were divided between those that suffered incarceration (study group) and a control group of those with a hernia who did not suffer incarceration. RESULTS: Twelve of the 99 patients (12.1%) suffered hernia incarceration, of which seven (7.1%) suffered incarceration in the first 90 days. One patient who suffered incarceration ultimately died from complications of the incarceration. When comparing all patients who suffered incarceration to controls, incarceration patients were found to have significantly higher albumin levels (mean 3.13 versus 2.73, p=0.02). When just considering those who had incarcerations in the first 90 days to controls, incarceration patients were less likely to have improvement in their ascites (p=0.04). CONCLUSIONS: Incarcerated hernias occur frequently after TIPS placement and can lead to significant morbidity and mortality. Clinicians should be aware of this complication and counsel patients on presenting symptoms prior to placement.


Assuntos
Ascite/terapia , Hérnia/etiologia , Derivação Portossistêmica Transjugular Intra-Hepática/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Ascite/sangue , Ascite/complicações , Feminino , Hérnia/patologia , Herniorrafia , Humanos , Cirrose Hepática/sangue , Cirrose Hepática/complicações , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Albumina Sérica/metabolismo
9.
Health Promot Pract ; 22(4): 502-511, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-32419515

RESUMO

Promotoras de salud (Spanish for female community health workers) are integral to efforts to enhance the health and well-being of Latinx individuals, families, and communities. The purpose of this study was to describe the challenges that promotoras face and the proposed solutions from the perspective of the promotoras themselves. Five promotoras who worked for a year as volunteers in a community-based participatory research study, Lazos Hispanos, participated in two group interviews. Eight challenges emerged-balancing their new work with their family commitments, handling their perceived imbalance of power with men, managing the emotional impact of hearing participants' problems, facing and handling the barriers imposed by having limited English language skills, feeling discouraged by the perception of ethnocentric beliefs and discrimination from some providers, feeling disheartened by the cultural beliefs of some Latinx participants, handling the lack of transportation for themselves and for the participants, and managing the burden of data collection for the research aspect of the program. The explanation of these challenges and the practical solutions they proposed are embedded in their intersecting identities. The solutions are a valuable addition to the practice of health promotion and community-based participatory research, particularly within Latinx communities.


Assuntos
Agentes Comunitários de Saúde , Pesquisa Participativa Baseada na Comunidade , Feminino , Promoção da Saúde , Hispânico ou Latino , Humanos , Idioma , Masculino
10.
Entropy (Basel) ; 23(8)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34441116

RESUMO

We perform a detailed computational study of the recently introduced Sombor indices on random networks. Specifically, we apply Sombor indices on three models of random networks: Erdös-Rényi networks, random geometric graphs, and bipartite random networks. Within a statistical random matrix theory approach, we show that the average values of Sombor indices, normalized to the order of the network, scale with the average degree. Moreover, we discuss the application of average Sombor indices as complexity measures of random networks and, as a consequence, we show that selected normalized Sombor indices are highly correlated with the Shannon entropy of the eigenvectors of the adjacency matrix.

11.
J Community Psychol ; 48(2): 464-481, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32074401

RESUMO

The goal of Lazos Hispanos is to enhance the health and well-being of the Latinx community through promotoras, who connect community members with service providers for multiple health and social needs. A community-based participatory research conceptual model framed the multimethod evaluation of promotoras, service providers, and community participants at baseline and at the 1-year follow up. The promotoras increased their self-efficacy and knowledge, felt a strong sense of commitment to the community, viewed themselves as a bridge between participants and providers, and felt empowered by their new role. Service providers valued the promotoras as their ambassadors in the community and Lazos Hispanos as central to connecting service providers, promotoras, and community members; they noted that this collaboration increased their accountability with the Latinx community. This multistakeholder evaluation highlights the depth of positive changes achieved during the first year and the challenges of a community-embedded project and the benefits and possibilities of calling upon theoretically informed evaluation models.


Assuntos
Agentes Comunitários de Saúde/organização & administração , Participação da Comunidade , Pesquisa Participativa Baseada na Comunidade , Conhecimentos, Atitudes e Prática em Saúde , Avaliação de Programas e Projetos de Saúde , Feminino , Hispânico ou Latino , Humanos , Entrevistas como Assunto , Modelos Teóricos , Motivação , Determinantes Sociais da Saúde
12.
J Prim Prev ; 41(3): 229-243, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32240452

RESUMO

U.S. Latinos face multiple inter-related barriers to access health and social services. Researchers and practitioners have called upon community-based participatory research (CBPR) to address such challenges and health disparities, with the community health worker-or promotoras-model evidencing positive outcomes. What is less clear, however, are the promising strategies to support the development of a multisystem, community-based promotoras program. In response, the current study applied a CBPR conceptual model as an organizing framework to develop a promotora program. Lazos Hispanos (Hispanic Links) was developed to enhance the health and well-being of Latinx residing in low-income communities in the Southeastern United States. This study highlights 16 lessons learned, anchored in the first two dimensions of the CBPR conceptual model: community context and partnership development. First, the community assessment and activities leading to Lazos Hispanos took nearly 2 years but were crucial to develop a strong basis for the program. Second, the development of a multicultural and interdisciplinary research team enriched every aspect of the program and enhanced culturally responsive community engagement. Selection, training, and ongoing support of the promotoras were fundamental to program success. Particularly important were the following: receiving mentorship from a successful promotora organization; delineating mutually agreed upon roles and responsibilities; following national training standards for community health workers; and, holding monthly meetings for training, support, and data collection. The engagement of community service providers as partners was facilitated by building upon existing community relationships, signing a memorandum of understanding that specified roles and responsibilities, conducting tours of provider facilities with the promotoras, and keeping providers abreast of the program via bi-annual community gatherings. The development process showed fidelity to the conceptual model. Lazos Hispanos has proven an asset to participants, the promotoras, and service providers as the program continues to develop a community-based, health supportive infrastructure.


Assuntos
Redes Comunitárias , Promoção da Saúde/organização & administração , Hispânico ou Latino , Agentes Comunitários de Saúde , Pesquisa Participativa Baseada na Comunidade , Humanos
13.
BMC Genet ; 20(1): 56, 2019 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-31299900

RESUMO

BACKGROUND: Ticks are a problem for cattle production mainly in tropical and subtropical regions, because they generate great economic losses. Acaricides and vaccines have been used to try to keep tick populations under control. This has been proven difficult given the resistance to acaricides and vaccines observed in ticks. Resistance to protein rBm86-based vaccines has been associated with the genetic diversity of Bm86 among the ectoparasite's populations. So far, neither genetic diversity, nor spatial distribution of circulating Bm86 haplotypes, have been studied within the Mexican territory. Here, we explored the genetic diversity of 125 Bm86 cDNA gene sequences from R. microplus from 10 endemic areas of Mexico by analyzing haplotype distribution patterns to help in understanding the population genetic structure of Mexican ticks. RESULTS: Our results showed an average nucleotide identity among the Mexican isolates of 98.3%, ranging from 91.1 to 100%. Divergence between the Mexican and Yeerongpilly (the Bm86 reference vaccine antigen) sequences ranged from 3.1 to 7.4%. Based on the geographic distribution of Bm86 haplotypes in Mexico, our results suggest gene flow occurrence within different regions of the Mexican territory, and even the USA. CONCLUSIONS: The polymorphism of Bm86 found in the populations included in this study, could account for the poor efficacy of the current Bm86 antigen based commercial vaccine in many regions of Mexico. Our data may contribute towards designing new, highly-specific, Bm86 antigen vaccine candidates against R. microplus circulating in Mexico.


Assuntos
Genes de Insetos , Variação Genética , Rhipicephalus/genética , Animais , Biologia Computacional/métodos , Bases de Dados Genéticas , Feminino , Genômica/métodos , Haplótipos , México , Filogenia
14.
Chaos ; 29(5): 053114, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31154780

RESUMO

The parameter plane investigation for a family of two-dimensional, nonlinear, and area contracting map is made. Several dynamical features in the system such as tangent, period-doubling, pitchfork, and cusp bifurcations were found and discussed together with cascades of period-adding, period-doubling, and the Feigeinbaum scenario. The presence of spring and saddle-area structures allow us to conclude that cubic homoclinic tangencies are present in the system. A set of complex sets such as streets with the same periodicity and the period-adding of spring-areas are observed in the parameter space of the mapping.

15.
Fam Process ; 58(1): 9-22, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30178616

RESUMO

We contend that the field of family therapy is undergoing a notable shift from second- to third-order thinking. We offer theoretical support and examples to demonstrate how third-order thinking provides a framework for integrating heightened sociocultural attunement into family therapy practice. We discuss the importance of third-order thinking relative to being prepared to invite families into third-order change. Finally, we offer a case example to show specific guidelines for third-order practice.


Afirmamos que el ámbito de la terapia familiar está sufriendo un cambio notable porque está pasando del pensamiento de segundo orden al pensamiento de tercer orden. Ofrecemos respaldo teórico y ejemplos para demostrar cómo el pensamiento de tercer oden ofrece un marco para integrar una mayor sensibilización sociocultural en la práctica de la terapia familiar. Debatimos la importancia del pensamiento de tercer orden relativa a estar preparados para invitar a las familias al cambio hacia el tercer orden. Finalmente, ofrecemos el ejemplo de un caso para mostrar pautas específicas sobre la práctica del tercer orden.


Assuntos
Medicina de Família e Comunidade/métodos , Terapia Familiar/ética , Teoria Psicológica , Justiça Social/psicologia , Humanos , Poder Psicológico
16.
Entropy (Basel) ; 21(1)2019 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33266802

RESUMO

We study the localization properties of the eigenvectors, characterized by their information entropy, of tight-binding random networks with balanced losses and gain. The random network model, which is based on Erdos-Rényi (ER) graphs, is defined by three parameters: the network size N, the network connectivity α , and the losses-and-gain strength γ . Here, N and α are the standard parameters of ER graphs, while we introduce losses and gain by including complex self-loops on all vertices with the imaginary amplitude i γ with random balanced signs, thus breaking the Hermiticity of the corresponding adjacency matrices and inducing complex spectra. By the use of extensive numerical simulations, we define a scaling parameter ξ ≡ ξ ( N , α , γ ) that fixes the localization properties of the eigenvectors of our random network model; such that, when ξ < 0.1 ( 10 < ξ ), the eigenvectors are localized (extended), while the localization-to-delocalization transition occurs for 0.1 < ξ < 10 . Moreover, to extend the applicability of our findings, we demonstrate that for fixed ξ , the spectral properties (characterized by the position of the eigenvalues on the complex plane) of our network model are also universal; i.e., they do not depend on the specific values of the network parameters.

17.
Chaos ; 28(5): 053120, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29857660

RESUMO

We study wave transmission G through quasi-one-dimensional waveguides with constant cross section. Constant cross section means that an infinite set of lines of the same length (that do not intersect each other) which are perpendicular to one boundary of the waveguide are also perpendicular to the other boundary. This makes the sign of the tangential velocity for all collision points of an arbitrary particle trajectory to stay constant, so that the classical or ray dynamics in the waveguide is unidirectional. In particular, we report the systematic enhancement of transmission in unidirectional corrugated waveguides when contrasting their transmission properties with those for equivalent constant-width waveguides (for which the classical dynamics is not unidirectional since particles moving in one direction along the waveguide can change its direction of motion). Also, we verify the universality of the distribution of transmissions P(G) in the diffusive ( ⟨G⟩>1) and localized ( ⟨G⟩≪1) regimes of transport. Moreover, we show that in the transition regime, ⟨G⟩∼1, P(G) is well described by the DMPK approach (the Fokker-Planck approach of Dorokhov, Mello, Pereyra, and Kumar) to bulk-disordered wires.

18.
Entropy (Basel) ; 20(4)2018 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33265391

RESUMO

We perform a detailed numerical study of the localization properties of the eigenfunctions of one-dimensional (1D) tight-binding wires with on-site disorder characterized by long-tailed distributions: For large ϵ , P ( ϵ ) ∼ 1 / ϵ 1 + α with α ∈ ( 0 , 2 ] ; where ϵ are the on-site random energies. Our model serves as a generalization of 1D Lloyd's model, which corresponds to α = 1 . In particular, we demonstrate that the information length ß of the eigenfunctions follows the scaling law ß = γ x / ( 1 + γ x ) , with x = ξ / L and γ ≡ γ ( α ) . Here, ξ is the eigenfunction localization length (that we extract from the scaling of Landauer's conductance) and L is the wire length. We also report that for α = 2 the properties of the 1D Anderson model are effectively reproduced.

19.
Scand J Immunol ; 85(4): 280-290, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28168862

RESUMO

This study was aimed to determine the profiles of serum cytokines (IL-1ß, TNF-α, IL-4, IL-5) and chemokines (MCP-1: monocyte chemoattract protein-1 and RANTES: regulated on activation normal T cell expressed and secreted) in individuals with an asthmatic versus a non-asthmatic background with bacterial, viral or mixed acute respiratory infection. Asthmatic (n = 14) and non-asthmatic (n = 29) patients with acute viral, bacterial or mixed (bacterial and viruses) respiratory infection were studied. Patients were also analysed as individuals with pneumonia or bronchitis. Healthy individuals with similar age and sex (n = 10) were used as controls. Cytokine/chemokine content in serum was determined by ELISA. Increased cytokine/chemokine concentration in asthmatic and non-asthmatic patients was observed. However, higher concentrations of chemokines (MCP-1 and RANTES) in asthmatic patients infected by viruses, bacteria or bacteria and viruses (mixed) than in non-asthmatic patients were observed. In general, viral and mixed infections were better cytokine/chemokine inducers than bacterial infection. Cytokine/chemokine expression was similarly increased in both asthmatic and non-asthmatic patients with pneumonia or bronchitis, except that RANTES remained at normal levels in bronchitis. Circulating cytokine profiles induced by acute viral, bacterial or mixed lung infection were not related to asthmatic background, except for chemokines that were increased in asthmatic status.


Assuntos
Asma/imunologia , Infecções Bacterianas/sangue , Bronquite/sangue , Quimiocinas/sangue , Pneumonia/sangue , Viroses/sangue , Adolescente , Adulto , Idoso , Asma/sangue , Infecções Bacterianas/imunologia , Bronquite/imunologia , Bronquite/microbiologia , Quimiocina CCL2/sangue , Quimiocina CCL5/sangue , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Interleucina-1beta/sangue , Interleucina-4/sangue , Interleucina-5/sangue , Masculino , Pessoa de Meia-Idade , Pneumonia/imunologia , Pneumonia/microbiologia , Fator de Necrose Tumoral alfa/sangue , Viroses/imunologia , Adulto Jovem
20.
J Synchrotron Radiat ; 21(Pt 6): 1333-46, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25343803

RESUMO

A fast algorithm for ring artefact reduction in high-resolution micro-tomography with synchrotron radiation is presented. The new method is a generalization of the one proposed by Titarenko and collaborators, with a complete sinogram restoration prior to reconstruction with classical algorithms. The generalized algorithm can be performed in linear time and is easy to implement. Compared with the original approach, with an explicit solution, this approach is fast through the use of the conjugate gradient method. Also, low/high-resolution sinograms can be restored using higher/lower-order derivatives of the projections. Using different order for the derivative is an advantage over the classical Titarenko's approach. Several numerical results using the proposed method are provided, supporting our claims.

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