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1.
PLoS Pathog ; 20(1): e1011880, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38271294

RESUMO

BACKGROUND: West Nile virus (WNV) outbreaks in birds, humans, and livestock have occurred in multiple areas in Europe and have had a significant impact on animal and human health. The patterns of emergence and spread of WNV in Europe are very different from those in the US and understanding these are important for guiding preparedness activities. METHODS: We mapped the evolution and spread history of WNV in Europe by incorporating viral genome sequences and epidemiological data into phylodynamic models. Spatially explicit phylogeographic models were developed to explore the possible contribution of different drivers to viral dispersal direction and velocity. A "skygrid-GLM" approach was used to identify how changes in environments would predict viral genetic diversity variations over time. FINDINGS: Among the six lineages found in Europe, WNV-2a (a sub-lineage of WNV-2) has been predominant (accounting for 73% of all sequences obtained in Europe that have been shared in the public domain) and has spread to at least 14 countries. In the past two decades, WNV-2a has evolved into two major co-circulating clusters, both originating from Central Europe, but with distinct dynamic history and transmission patterns. WNV-2a spreads at a high dispersal velocity (88km/yr-215 km/yr) which is correlated to bird movements. Notably, amongst multiple drivers that could affect the spread of WNV, factors related to land use were found to strongly influence the spread of WNV. Specifically, the intensity of agricultural activities (defined by factors related to crops and livestock production, such as coverage of cropland, pasture, cultivated and managed vegetation, livestock density) were positively associated with both spread direction and velocity. In addition, WNV spread direction was associated with high coverage of wetlands and migratory bird flyways. CONCLUSION: Our results suggest that-in addition to ecological conditions favouring bird- and mosquito- presence-agricultural land use may be a significant driver of WNV emergence and spread. Our study also identified significant gaps in data and the need to strengthen virological surveillance in countries of Central Europe from where WNV outbreaks are likely seeded. Enhanced monitoring for early detection of further dispersal could be targeted to areas with high agricultural activities and habitats of migratory birds.


Assuntos
Febre do Nilo Ocidental , Vírus do Nilo Ocidental , Animais , Humanos , Vírus do Nilo Ocidental/genética , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/veterinária , Filogeografia , Europa (Continente)/epidemiologia , Surtos de Doenças
2.
J Gen Virol ; 105(7)2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38975739

RESUMO

The 2020/2021 epidemic in Europe of highly pathogenic avian influenza virus (HPAIV) of subtype H5 surpassed all previously recorded European outbreaks in size, genotype constellations and reassortment frequency and continued into 2022 and 2023. The causative 2.3.4.4b viral lineage proved to be highly proficient with respect to reassortment with cocirculating low pathogenic avian influenza viruses and seems to establish an endemic status in northern Europe. A specific HPAIV reassortant of the subtype H5N3 was detected almost exclusively in red knots (Calidris canutus islandica) in December 2020. It caused systemic and rapidly fatal disease leading to a singular and self-limiting mass mortality affecting about 3500 birds in the German Wadden Sea, roughly 1 % of the entire flyway population of islandica red knots. Phylogenetic analyses revealed that the H5N3 reassortant very likely had formed in red knots and remained confined to this species. While mechanisms of virus circulation in potential reservoir species, dynamics of spill-over and reassortment events and the roles of environmental virus sources remain to be identified, the year-round infection pressure poses severe threats to endangered avian species and prompts adaptation of habitat and species conservation practices.


Assuntos
Vírus da Influenza A , Influenza Aviária , Filogenia , Vírus Reordenados , Animais , Influenza Aviária/virologia , Influenza Aviária/epidemiologia , Europa (Continente)/epidemiologia , Vírus da Influenza A/genética , Vírus da Influenza A/classificação , Vírus da Influenza A/patogenicidade , Vírus Reordenados/genética , Surtos de Doenças/veterinária , Charadriiformes/virologia , Aves/virologia
3.
J Gen Virol ; 104(4)2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37014781

RESUMO

Mass mortality was observed among colony-breeding seabirds in the German Wadden Sea area of the North Sea during the summer months of 2022. Several species' colonies were affected, most notably sandwich terns (Thalasseus sandvicensis), common terns (Sterna hirundo) and Germany's only northern gannet (Morus bassanus) colony on the island of Heligoland. Mortality in some tern colonies reached 40%, while other colonies were almost spared. In all cases, infections with the high-pathogenicity avian influenza virus (HPAIV) subtype H5N1 of clade 2.3.4.4b were identified to have caused the epidemic. Phylogenetic analysis of whole-genome sequences revealed that the outbreaks were dominated by two genotypes, Ger-10-21 N1.2 and Ger-10-21 N1.5, previously identified in Germany. Spatiotemporal analyses of phylogenetic data suggested that these viruses could have entered the continental North Sea coastal region via the British Isles. A close linkage of viruses from tern colonies in the German Wadden Sea was evident with further connections to breeding colonies in Belgium and the Netherlands, and further spread to Denmark and Poland. Several of the affected species are endangered, such that negative effects of epizootic HPAIV infections on populations are feared, with uncertain long-term consequences.


Assuntos
Virus da Influenza A Subtipo H5N1 , Influenza Aviária , Animais , Influenza Aviária/epidemiologia , Virus da Influenza A Subtipo H5N1/genética , Filogenia , Virulência , Aves , Genótipo
4.
Emerg Infect Dis ; 28(12): 2383-2388, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36261139

RESUMO

Highly pathogenic avian influenza viruses (HPAIVs) of hemagglutinin type H5 and clade 2.3.4.4b have widely spread within the northern hemisphere since 2020 and threaten wild bird populations, as well as poultry production. We present phylogeographic evidence that Iceland has been used as a stepping stone for HPAIV translocation from northern Europe to North America by infected but mobile wild birds. At least 2 independent incursions of HPAIV H5N1 clade 2.3.4.4b assigned to 2 hemagglutinin clusters, B1 and B2, are documented for summer‒autumn 2021 and spring 2022. Spread of HPAIV H5N1 to and among colony-breeding pelagic avian species in Iceland is ongoing. Potentially devastating effects (i.e., local losses >25%) on these species caused by extended HPAIV circulation in space and time are being observed at several affected breeding sites throughout the North Atlantic.


Assuntos
Virus da Influenza A Subtipo H5N1 , Vírus da Influenza A , Influenza Aviária , Animais , Influenza Aviária/epidemiologia , Islândia/epidemiologia , Hemaglutininas , Vírus da Influenza A/genética , Animais Selvagens , Aves , Europa (Continente)/epidemiologia , América do Norte/epidemiologia , Filogenia
5.
J Immunol ; 204(12): 3217-3226, 2020 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-32341061

RESUMO

The glycoprotein CD83 is known to be expressed by different immune cells including activated CD4+Foxp3+ regulatory T cells (Tregs) and CD4+Foxp3- conventional T cells. However, the physiological function of endogenous CD83 in CD4+ T cell subsets is still unclear. In this study, we have generated a new CD83flox mouse line on BALB/c background, allowing for specific ablation of CD83 in T cells upon breeding with CD4-cre mice. Tregs from CD83flox/flox/CD4-cretg/wt mice had similar suppressive activity as Tregs from CD83flox/flox/CD4-crewt/wt wild-type littermates, suggesting that endogenous CD83 expression is dispensable for the inhibitory capacity of Tregs. However, CD83-deficient CD4+ conventional T cells showed elevated proliferation and IFN-γ secretion as well as an enhanced capacity to differentiate into Th1 cells and Th17 cells upon stimulation in vitro. T cell-specific ablation of CD83 expression resulted in aggravated contact hypersensitivity reaction accompanied by enhanced CD4+ T cell activation. Moreover, adoptive transfer of CD4+CD45RBhigh T cells from CD83flox/flox/CD4-cretg /wt mice into Rag2-deficient mice elicited more severe colitis associated with increased serum concentrations of IL-12 and elevated CD40 expression on CD11c+ dendritic cells (DCs). Strikingly, DCs from BALB/c mice cocultured with CD83-deficient CD4+ conventional T cells showed enhanced CD40 expression and IL-12 secretion compared with DCs cocultured with CD4+ conventional T cells from CD83flox/flox/CD4-crewt/wt wild-type mice. In summary, these results indicate that endogenous CD83 expression in CD4+ conventional T cells plays a crucial role in controlling CD4+ T cell responses, at least in part, by regulating the activity of CD11c+ DCs.


Assuntos
Antígenos CD/imunologia , Linfócitos T CD4-Positivos/imunologia , Imunidade/imunologia , Imunoglobulinas/imunologia , Inflamação/imunologia , Glicoproteínas de Membrana/imunologia , Transferência Adotiva/métodos , Animais , Células Dendríticas/imunologia , Feminino , Interferon gama/imunologia , Interleucina-12/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Linfócitos T Reguladores/imunologia , Células Th1/imunologia , Células Th17/imunologia , Antígeno CD83
6.
BMC Biotechnol ; 20(1): 47, 2020 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-32854679

RESUMO

BACKGROUND: Approximately 40% of prescribed drugs exert their activity via GTP-binding protein-coupled receptors (GPCRs). Once activated, these receptors cause transient changes in the concentration of second messengers, e.g., cyclic adenosine 3',5'-monophosphate (cAMP). Specific and efficacious genetically encoded biosensors have been developed to monitor cAMP fluctuations with high spatial and temporal resolution in living cells or tissue. A well characterized biosensor for cAMP is the Förster resonance energy transfer (FRET)-based Epac1-camps protein. Pharmacological characterization of newly developed ligands acting at GPCRs often includes numerical quantification of the second messenger amount that was produced. RESULTS: To quantify cellular cAMP concentrations, we bacterially over-expressed and purified Epac1-camps and applied the purified protein in a cell-free detection assay for cAMP in a multi-well format. We found that the biosensor can detect as little as 0.15 pmol of cAMP, and that the sensitivity is not impaired by non-physiological salt concentrations or pH values. Notably, the assay tolerated desiccation and storage of the protein without affecting Epac1-camps cyclic nucleotide sensitivity. CONCLUSIONS: We found that determination cAMP in lysates obtained from cell assays or tissue samples by purified Epac1-camps is a robust, fast, and sensitive assay suitable for routine and high throughput analyses.


Assuntos
Transferência Ressonante de Energia de Fluorescência/métodos , Fluorescência , Nucleotídeos Cíclicos , Técnicas Biossensoriais/métodos , Técnicas de Cultura de Células , Clonagem Molecular , AMP Cíclico , Escherichia coli/genética , Fatores de Troca do Nucleotídeo Guanina , Concentração de Íons de Hidrogênio , Nucleotídeos Cíclicos/genética , Receptores Acoplados a Proteínas G , Proteínas Recombinantes
7.
Occup Environ Med ; 77(9): 611-616, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32571792

RESUMO

OBJECTIVES: Chronic obstructive pulmonary disease and silicosis are associated with exposure to crystalline silica. We determined the exposure to respirable crystalline silica and estimated exposure-response relationships between cumulative exposure and pulmonary function in outdoor rock drillers. METHODS: 136 rock drillers and 48 referents were recruited from three heavy construction companies. 98 air samples were collected by personal sampling for determination of respirable particulate matter and crystalline silica. Information about individual job tasks, type of drilling equipment and years of exposure in different job categories was obtained by interview. Cumulative exposure to crystalline silica was calculated for all workers. Pulmonary function was assessed by spirometry. A subgroup of 39 subjects with high cumulative exposure to crystalline silica underwent high-resolution computed tomography (HRCT). RESULTS: Cumulative exposure (mean (min-max)) to crystalline silica was 0.69 mgÙ years m-3 (0.01-5.89) in the exposed group. Mean time of exposure among rock drillers was 10.7 years (1-42). Compared with referents, the rock drillers had a lower forced expiratory volume in one second/forced vital capacity ratio (79.4 vs 81.4, p<0.05) and maximal mid-expiratory flow% (85.6 vs 93.9, p<0.05). Further, by stratifying the exposed workers into three equally large groups, a dose-response relationship was demonstrated in the highest exposed group, also in never smokers, at a mean cumulative exposure of 21.7 years at 0.08 mgÙ m-3/years. Silicosis was not detected in HRCT, but other patterns of fibrosis and emphysema were seen. CONCLUSIONS: Outdoor rock drillers exposed to crystalline silica had significantly lower pulmonary function than referents, and signs of airflow obstruction. Silicosis was not detected.


Assuntos
Pneumopatias Obstrutivas/diagnóstico por imagem , Pneumopatias Obstrutivas/fisiopatologia , Exposição Ocupacional/efeitos adversos , Dióxido de Silício/efeitos adversos , Adulto , Idoso , Indústria da Construção , Humanos , Masculino , Pessoa de Meia-Idade , Noruega/epidemiologia , Material Particulado/efeitos adversos , Fibrose Pulmonar , Testes de Função Respiratória , Silicose , Fumantes , Tomografia Computadorizada por Raios X
8.
Scand Cardiovasc J ; 54(4): 220-226, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32408833

RESUMO

Objectives. In grading of aortic stenosis, two-dimensional transthoracic echocardiography (2D TTE) routinely results in underestimation of the left ventricular outflow tract (LVOT) area, and hence the aortic valve area (AVA). We investigated whether three-dimensional (3D) TTE measurements of the LVOT would be more accurate. We evaluated the feasibility, agreement and inter-observer variability of 3D TTE LVOT measurements with computed tomography (CT) and Haegar sizers as reference. Design. Sixty-one patients with severe aortic stenosis were examined with 2D and 3D TTE. 41 had CT and 13 also had perioperative Haegar sizing. Pearson's correlation and Bland-Altman plots were used to compare methods. Inter-observer variability was tested for 2D and 3D TTE. Trial registration: Current research information system in Norway (CRISTIN). Id: 555249. Results. Feasibility was 67% with 3D TTE and 100% with 2D TTE and CT. Mean LVOT area for 2D, 3D, CT and Haegar sizers were 3.7 ± 0.6 cm2, 4.0 ± 0.9 cm2, 5.2 ± 0.8 cm2 and 4.4 ± 1.0 cm2 respectively. Bias and limits of agreements for 2D TTE was 1.5 ± 1.3 cm2, compared with CT and 0.4 ± 1.5 cm2 with Haegar sizers. Corresponding results for 3D TTE were 1.2 ± 1.6 cm2 and 0.2 ± 1.8 cm2. Intraclass correlation coefficients for LVOT area were 0.62 for 3D and 0.86 for 2D. Conclusions. 2D TTE showed better feasibility and inter-observer variability in measurements of LVOT than 3D TTE. Both echocardiographic methods underestimated LVOT area compared to CT and Haegar sizers. These observations suggest that 2D TTE is still preferable to 3D TTE in the assessment of aortic stenosis.


Assuntos
Estenose da Valva Aórtica/diagnóstico por imagem , Valva Aórtica/diagnóstico por imagem , Ecocardiografia Doppler , Ecocardiografia Tridimensional , Ventrículos do Coração/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Valva Aórtica/fisiopatologia , Estenose da Valva Aórtica/fisiopatologia , Estudos Transversais , Estudos de Viabilidade , Ventrículos do Coração/fisiopatologia , Humanos , Interpretação de Imagem Assistida por Computador , Variações Dependentes do Observador , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Índice de Gravidade de Doença
9.
Int J Mol Sci ; 21(8)2020 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-32316452

RESUMO

The importance of intrinsically disordered late embryogenesis abundant (LEA) proteins in the tolerance to abiotic stresses involving cellular dehydration is undisputed. While structural transitions of LEA proteins in response to changes in water availability are commonly observed and several molecular functions have been suggested, a systematic, comprehensive and comparative study of possible underlying sequence-structure-function relationships is still lacking. We performed molecular dynamics (MD) simulations as well as spectroscopic and light scattering experiments to characterize six members of two distinct, lowly homologous clades of LEA_4 family proteins from Arabidopsis thaliana. We compared structural and functional characteristics to elucidate to what degree structure and function are encoded in LEA protein sequences and complemented these findings with physicochemical properties identified in a systematic bioinformatics study of the entire Arabidopsis thaliana LEA_4 family. Our results demonstrate that although the six experimentally characterized LEA_4 proteins have similar structural and functional characteristics, differences concerning their folding propensity and membrane stabilization capacity during a freeze/thaw cycle are obvious. These differences cannot be easily attributed to sequence conservation, simple physicochemical characteristics or the abundance of sequence motifs. Moreover, the folding propensity does not appear to be correlated with membrane stabilization capacity. Therefore, the refinement of LEA_4 structural and functional properties is likely encoded in specific patterns of their physicochemical characteristics.


Assuntos
Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Biologia Computacional/métodos , Modelos Moleculares , Conformação Molecular , Simulação de Dinâmica Molecular , Dobramento de Proteína , Estresse Fisiológico
10.
J Neurosci ; 38(42): 8922-8942, 2018 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-30150361

RESUMO

Stress is a precipitating agent in neuropsychiatric disease and initiates relapse to drug-seeking behavior in addicted patients. Targeting the stress system in protracted abstinence from drugs of abuse with anxiolytics may be an effective treatment modality for substance use disorders. α2A-adrenergic receptors (α2A-ARs) in extended amygdala structures play key roles in dampening stress responses. Contrary to early thinking, α2A-ARs are expressed at non-noradrenergic sites in the brain. These non-noradrenergic α2A-ARs play important roles in stress responses, but their cellular mechanisms of action are unclear. In humans, the α2A-AR agonist guanfacine reduces overall craving and uncouples craving from stress, yet minimally affects relapse, potentially due to competing actions in the brain. Here, we show that heteroceptor α2A-ARs postsynaptically enhance dorsal bed nucleus of the stria terminalis (dBNST) neuronal activity in mice of both sexes. This effect is mediated by hyperpolarization-activated cyclic nucleotide-gated cation channels because inhibition of these channels is necessary and sufficient for excitatory actions. Finally, this excitatory action is mimicked by clozapine-N-oxide activation of the Gi-coupled DREADD hM4Di in dBNST neurons and its activation elicits anxiety-like behavior in the elevated plus maze. Together, these data provide a framework for elucidating cell-specific actions of GPCR signaling and provide a potential mechanism whereby competing anxiogenic and anxiolytic actions of guanfacine may affect its clinical utility in the treatment of addiction.SIGNIFICANCE STATEMENT Stress affects the development of neuropsychiatric disorders including anxiety and addiction. Guanfacine is an α2A-adrenergic receptor (α2A-AR) agonist with actions in the bed nucleus of the stria terminalis (BNST) that produces antidepressant actions and uncouples stress from reward-related behaviors. Here, we show that guanfacine increases dorsal BNST neuronal activity through actions at postsynaptic α2A-ARs via a mechanism that involves hyperpolarization-activated cyclic nucleotide gated cation channels. This action is mimicked by activation of the designer receptor hM4Di expressed in the BNST, which also induces anxiety-like behaviors. Together, these data suggest that postsynaptic α2A-ARs in BNST have excitatory actions on BNST neurons and that these actions can be phenocopied by the so-called "inhibitory" DREADDs, suggesting that care must be taken regarding interpretation of data obtained with these tools.


Assuntos
Ansiedade/fisiopatologia , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/fisiologia , Neurônios/fisiologia , Receptores Adrenérgicos alfa 2/fisiologia , Núcleos Septais/fisiologia , Estresse Psicológico/fisiopatologia , Agonistas de Receptores Adrenérgicos alfa 2/administração & dosagem , Animais , Catecolaminas/metabolismo , Feminino , Guanfacina/administração & dosagem , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo , Núcleos Septais/diagnóstico por imagem , Núcleos Septais/metabolismo
11.
Transpl Int ; 31(1): 82-91, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28865096

RESUMO

The predictive value of coronary artery calcium (CAC) in heart transplant (HTX) patients is not established. We explored if the absence of CAC on computed tomography (CT) could exclude moderate and severe cardiac allograft vasculopathy [CAV2-3 ; the International Society for Heart and Lung Transplantation (ISHLT) recommended nomenclature] and significant coronary artery stenosis (diameter reduction ≥50%) and predict long-term clinical outcomes. HTX recipients (n = 133) were prospectively included and underwent CT for CAC scoring and invasive coronary angiography (ICA) 7.8 ± 5.0 years after HTX. CAC was detected in 73 (55%) patients. The absence of CAC on CT had a negative predictive value of 97% for ISHLT CAV2-3 and 88% for significant stenosis on ICA. During 7.5 ± 2.6 years of follow-up after CAC CT (n = 127), there were 57 (45%) nonfatal major adverse cardiac events and 23 (18%) deaths or graft losses registered as first events. Patients with CAC had significantly more events (P = 0.011). In an adjusted Cox regression analysis, the presence of CAC was significantly associated with a negative outcome (HR 1.8, 95% CI 1.1-3.0; P = 0.023). The absence of CAC predicted low prevalences of ISHLT CAV2-3 and significant coronary artery stenosis in HTX patients. The presence of CACS was significantly associated with a worse long-term outcome.


Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Transplante de Coração , Complicações Pós-Operatórias/diagnóstico por imagem , Calcificação Vascular/diagnóstico por imagem , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Tomografia Computadorizada por Raios X
12.
Int Arch Occup Environ Health ; 91(3): 317-326, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29196803

RESUMO

PURPOSE: The aim of this study was to assess short-term changes in pulmonary function in drill floor workers currently exposed to airborne contaminants generated as a result of drilling offshore. We also aimed to study the prevalence of pulmonary fibrosis using high-resolution computed tomography (HRCT) scans of another group of previously exposed drill floor workers. METHODS: Pulmonary function was measured before and after a 14-day work period in a follow-up study of 65 drill floor workers and 65 referents. Additionally, 57 other drill floor workers exposed to drilling fluids during the 1980s were examined with HRCT of the lungs in a cross-sectional study. RESULTS: The drill floor workers had a statistically significant decline in forced expiratory volume in 1 s (FEV1) across the 14-day work period after adjustment for diurnal variations in pulmonary function (mean 90 mL, range 30-140 mL), while the small decline among the referents (mean 20 mL, range - 30 to 70 mL) was not of statistical significance. Larger declines in FEV1 among drill workers were associated with the fewer number of days of active drilling. There were no signs of pulmonary fibrosis related to oil mist exposure among the other previously exposed drill floor workers. CONCLUSION: After 14 days offshore, a statistically significant decline in FEV1 was observed in the drill floor workers, which may not be related to oil mist exposure. No pulmonary fibrosis related to oil mist exposure was observed.


Assuntos
Volume Expiratório Forçado , Doenças Profissionais/epidemiologia , Exposição Ocupacional/efeitos adversos , Indústria de Petróleo e Gás , Adulto , Idoso , Poluentes Ocupacionais do Ar , Estudos Transversais , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Óleos/efeitos adversos , Fibrose Pulmonar/epidemiologia , Testes de Função Respiratória , Tomografia Computadorizada por Raios X
13.
Acta Radiol ; 59(9): 1066-1073, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29260577

RESUMO

Background Cardiac allograft vasculopathy (CAV) is an accelerated form of atherosclerosis unique to heart transplant (HTX) patients. Purpose To investigate the detection of significant coronary artery stenosis and CAV, determinants of image quality, and the radiation dose in coronary computed tomography angiography (CCTA) of HTX patients with 64-slice multidetector CT (64-MDCT). Material and Methods Fifty-two HTX recipients scheduled for invasive coronary angiography (ICA) were prospectively enrolled and underwent CCTA before ICA with intravascular ultrasound (IVUS). Results Interpretable CCTA images were acquired in 570 (95%) coronary artery segments ≥2 mm in diameter. Sensitivity, specificity, and positive and negative predictive values of CCTA for the detection of segments with significant stenosis (lumen reduction ≥50%) on ICA were 100%, 98%, 7.7%, and 100%, respectively. Twelve significant stenoses were located in segments with uninterpretable image quality or vessel diameter <2 mm; only one was eligible for intervention. IVUS detected CAV (maximal intimal thickness ≥0.5 mm) in 33/41 (81%) patients; CCTA and ICA identified CAV (any wall or luminal irregularity) in 18 (44%) and 14 (34%) of these 33 patients, respectively. The mean estimated radiation dose was 19.0 ± 3.4 mSv for CCTA and 5.7 ± 3.3 mSv for ICA ( P < 0.001). Conclusion CCTA with interpretable image quality had a high negative predictive value for ruling out significant stenoses suitable for intervention. The modest detection of CAV by CCTA implied a limited value in identifying subtle CAV. The high estimated radiation dose for 64-MDCT is of concern considering the need for repetitive examinations in the HTX population.


Assuntos
Angiografia por Tomografia Computadorizada/métodos , Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Transplante de Coração , Complicações Pós-Operatórias/diagnóstico por imagem , Técnicas de Imagem de Sincronização Cardíaca , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Doses de Radiação , Sensibilidade e Especificidade , Ultrassonografia de Intervenção
14.
J Exp Biol ; 220(Pt 8): 1400-1404, 2017 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-28167801

RESUMO

Genetic manipulation of cells and tissue by RNA interference has significantly contributed to the functional characterization of individual proteins and their role in physiological processes. Despite its versatility, RNA interference can have detrimental side effects, including reduced cell viability. We applied recombinant adeno-associated viruses by stereotaxic injection into the murine hippocampus to express different short hairpin RNA (shRNA) constructs along with eGFP. Tissue responses were assessed immunohistochemically for up to 8 weeks post-infection. Strong hippocampal degeneration and tissue atrophy was observed, most likely induced by high shRNA expression. The effect was entirely absent in mice injected with vectors driving only expression of eGFP. Active caspase-3 (Casp-3) and glial fibrillary acidic protein (GFAP) were identified as molecular markers and early indicators of adverse tissue responses. Our findings also demonstrate that detrimental effects of high shRNA expression in hippocampal tissue can be monitored even before the onset of tissue degeneration.


Assuntos
Apoptose , Caspase 3/análise , Proteína Glial Fibrilar Ácida/análise , Hipocampo/patologia , RNA Interferente Pequeno/efeitos adversos , Animais , Células Cultivadas , Dependovirus/genética , Expressão Gênica , Proteínas de Fluorescência Verde/genética , Hipocampo/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/metabolismo , Neurônios/patologia , Interferência de RNA , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/genética
15.
BMC Cell Biol ; 16: 18, 2015 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-26141616

RESUMO

BACKGROUND: Cardiac rhythmic activity is initiated in functionally specialized areas of the heart. Hyperpolarization-activated and cyclic nucleotide-gated (HCN) channels are fundamental for these processes of cardiac physiology. RESULTS: Here we investigated transcript and protein expression patterns of HCN channels in HL-1 cardiomyocytes using a combination of quantitative PCR analysis and immunocytochemistry. Gene expression profiles of hcn1, hcn2 and hcn4 were acutely affected during HL-1 cell propagation. In addition, distinct expression patterns were uncovered for HCN1, HCN2 and HCN4 proteins. CONCLUSIONS: Our results suggest that HCN channel isoforms might be involved in the concerted differentiation of HL-1 cells and may indirectly affect the occurrence of contractile HL-1 cell activity. We expect that these findings will promote studies on other molecular markers that contribute to cardiac physiology.


Assuntos
Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/metabolismo , Canais de Potássio/metabolismo , Animais , Encéfalo/metabolismo , Linhagem Celular , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/genética , Camundongos , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Canais de Potássio/genética , Transdução de Sinais , Transcriptoma
16.
Ann Rheum Dis ; 74(8): 1515-21, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24695010

RESUMO

OBJECTIVE: To compare arterial haemodynamics in adults with long-term juvenile idiopathic arthritis (JIA) to that of healthy controls, and explore the influence of traditional cardiovascular risk factors and disease characteristics on arterial haemodynamics plus coronary artery calcification. METHODS: 87 JIA patients (median age 38.4 years) with persistently active disease at least 15 years after disease onset (registered by longitudinal follow-up), were re-examined after median 29 years and compared with 87 matched controls. Arterial haemodynamics were characterised by arterial stiffness and blood pressure. Sphygmocor was used to measure the arterial stiffness markers pulse wave velocity (PWV) and augmentation index (AIx). Coronary calcification was assessed by CT. RESULTS: Compared to controls, patients had significantly higher PWV (7.2 vs 6.9 m/s, p=0.035), and systolic and diastolic blood pressure (SBP, p=0.050 and DBP, p=0.029). AIx was numerically higher in the patients compared to the controls, but no statistically significant difference was found. Coronary calcification was present in 22 (26%) of the patients. Daily smoking was more frequent (p=0.043), and insulin resistance was higher (p=0.034) in patients than controls.In patients, DBP, but no disease variables were determinants of PWV. Disease variables as well as traditional cardiovascular risk factors were associated with higher AIx, DBP and the presence of coronary calcification. CONCLUSIONS: JIA patients with long-term active disease had altered arterial haemodynamics compared with controls in our study. PWV was mainly determined by increased DBP, a parameter that again was associated with JIA disease and treatment variables.


Assuntos
Artrite Juvenil/epidemiologia , Artrite Juvenil/fisiopatologia , Calcificação Vascular/epidemiologia , Rigidez Vascular/fisiologia , Adulto , Pressão Sanguínea/fisiologia , Hemodinâmica , Humanos , Análise de Onda de Pulso , Fatores de Risco , Fumar/epidemiologia
17.
Rheumatology (Oxford) ; 54(8): 1420-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25740830

RESUMO

OBJECTIVE: To retrospectively evaluate the efficacy and safety of rituximab (Rtx) treatment in patients with anti-synthetase syndrome (ASS) and severe interstitial lung disease (ILD). METHODS: Patients with severe ILD and >12 months follow-up post-Rtx were identified from the Oslo University Hospital ASS cohort (n = 112). Clinical data, including pulmonary function tests (PFTs), were retrospectively collected from medical reports. Extent of ILD pre-, and post-Rtx was scored on thin-section high-resolution CT (HRCT) images and expressed as a percentage of total lung volume. Muscle strength was evaluated by manual muscle testing of eight muscle groups (MMT8). RESULTS: Altogether, 34/112 ASS patients had received Rtx; 24/34 had severe ILD and >12 months follow-up post-Rtx (median 52 months). In these 24 patients, the median percentage of predicted forced vital capacity, forced expiratory volume in 1 s (FEV1) and diffusing capacity of the lungs for carbon monoxide (DLCO) increased by 24%, 22% and 17%, respectively, post-Rtx. Seven patients (all with disease duration <12 months and/or acute onset/exacerbation of ILD) had >30% improvement in all three PFTs. HRCT analysis showed a median 34% reduction in ILD extent post-Rtx. MMT8 score increased post-Rtx. During follow-up, 7/34 (21%) Rtx-treated ASS patients died; 6/7 deaths were related to infections. The mortality rate in the Rtx-treated group was comparable to that of the remaining ASS cohort (25/78 deceased; 32%). CONCLUSION: This study, which included 24 Rtx-treated ASS patients with severe ILD, reports improved PFTs after a median 52 months follow-up post-Rtx. The best outcome was observed in patients with a disease duration <12 months and/or acute onset/exacerbation of ILD. The study indicates that Rtx could be a treatment option for selected ASS patients, but infections should be given attention.


Assuntos
Anticorpos Monoclonais Murinos/uso terapêutico , Antirreumáticos/uso terapêutico , Doenças Pulmonares Intersticiais/tratamento farmacológico , Doenças Pulmonares Intersticiais/etiologia , Miosite/complicações , Adulto , Idoso , Estudos de Coortes , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Pulmão/diagnóstico por imagem , Doenças Pulmonares Intersticiais/fisiopatologia , Masculino , Pessoa de Meia-Idade , Força Muscular/fisiologia , Miosite/fisiopatologia , Testes de Função Respiratória , Estudos Retrospectivos , Rituximab , Índice de Gravidade de Doença , Tomografia Computadorizada por Raios X , Resultado do Tratamento
18.
Neuron ; 112(3): 421-440.e7, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-37979584

RESUMO

Most cognitive functions involving the prefrontal cortex emerge during late development. Increasing evidence links this delayed maturation to the protracted timeline of prefrontal development, which likely does not reach full maturity before the end of adolescence. However, the underlying mechanisms that drive the emergence and fine-tuning of cognitive abilities during adolescence, caused by circuit wiring, are still unknown. Here, we continuously monitored prefrontal activity throughout the postnatal development of mice and showed that an initial activity increase was interrupted by an extensive microglia-mediated breakdown of activity, followed by the rewiring of circuit elements to achieve adult-like patterns and synchrony. Interfering with these processes during adolescence, but not adulthood, led to a long-lasting microglia-induced disruption of prefrontal activity and neuronal morphology and decreased cognitive abilities. These results identified a nonlinear reorganization of prefrontal circuits during adolescence and revealed its importance for adult network function and cognitive processing.


Assuntos
Cognição , Córtex Pré-Frontal , Adolescente , Humanos , Cognição/fisiologia , Córtex Pré-Frontal/fisiologia , Neurônios/fisiologia
19.
J Clin Ultrasound ; 41(1): 26-31, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22927091

RESUMO

BACKGROUND: Color Doppler ultrasound (CDUS) has a potential of early detection of post biopsy bleeding. We describe CDUS guidance in planning, acquisition, and, in the case of bleeding, compression of the needle tract in biopsy procedures of kidney transplants. METHODS: Eighty-three kidney transplant biopsy procedures performed on clinical indication were performed in 71 adult patients, 25 women, mean age 51 years, using CDUS and 18-G biopsy needles. Bleeding needle tracts were compressed using CDUS guidance. RESULTS: CDUS immediately detected blood leakage and facilitated compression of the bleeding needle tract in 34 (41%) of the 83 procedures, including 53 (25%) of 215 needle passes. In 34 bleeding procedures, the mean duration of the longest bleeding time after a needle pass was 124 seconds (median, 20 seconds; range, 3-1440 seconds). In 12 of these procedures (35%), the bleeding time was 30 seconds or more. In six procedures (18%), a bleeding of 120 seconds or more was observed. Complications included seven small hematomas. Five hematomas developed in procedures where the longest duration CD bleeding was 120 seconds or more. CONCLUSIONS: CDUS detects bleeding and facilitates direct transducer compression of the needle tract in a substantial portion of biopsy procedures of kidney transplants. Only minor hematomas occurred.


Assuntos
Biópsia por Agulha/efeitos adversos , Hemorragia/diagnóstico por imagem , Transplante de Rim/patologia , Ultrassonografia Doppler em Cores , Adulto , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Feminino , Hemorragia/etiologia , Humanos , Transplante de Rim/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Adulto Jovem
20.
Materials (Basel) ; 16(10)2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37241233

RESUMO

We propose the use of Optical Coherence Tomography (OCT) as a tool for the quality control of 3-D-printed ceramics. Test samples with premeditated defects, namely single- and two-component samples of zirconia, titania, and titanium suboxides, were printed by stereolithography-based DLP (Digital Light Processing) processes. The OCT tomograms obtained on the green samples showed the capability of the method to visualize variations in the layered structure of the samples as well as the presence of cracks and inclusions at depths up to 130 µm, as validated by SEM images. The structural information was visible in cross-sectional images as well as in plan-view images. The optical signal measured from the printed zirconia oxide and titanium oxide samples showed strong attenuation with depth and could be fit with an exponential decay curve. The variations of the decay parameter correlated very well with the presence of defects and material variation. When used as an imaging quantity, the decay parameter projects the position of the defects into 2-D (X,Y) coordinates. This procedure can be used in real time, it reduces the data volume up to 1000 times, and allows for faster subsequent data analysis and transfer. Tomograms were also obtained on sintered samples. The results showed that the method can detect changes in the optical properties of the green ceramics caused by sintering. Specifically, the zirconium oxide samples became more transparent to the light used, whereas the titanium suboxide samples became entirely opaque. In addition, the optical response of the sintered zirconium oxide showed variations within the imaged volume, indicating material density variations. The results presented in this study show that OCT provides sufficient structural information on 3-D-printed ceramics and can be used as an in-line tool for quality control.

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