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1.
Sci Rep ; 12(1): 18694, 2022 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-36333445

RESUMO

SARS-CoV-2 exhibits a diverse host species range with variable outcomes, enabling differential host susceptibility studies to assess suitability for pre-clinical countermeasure and pathogenesis studies. Baseline virological, molecular and pathological outcomes were determined among multiple species-one Old World non-human primate (NHP) species (cynomolgus macaques), two New World NHP species (red-bellied tamarins; common marmosets) and Syrian hamsters-following single-dose, atraumatic intranasal administration of SARS-CoV-2/Victoria-01. After serial sacrifice 2, 10 and 28-days post-infection (dpi), hamsters and cynomolgus macaques displayed differential virus biodistribution across respiratory, gastrointestinal and cardiovascular systems. Uniquely, New World tamarins, unlike marmosets, exhibited high levels of acute upper airway infection, infectious virus recovery associated with mild lung pathology representing a host previously unrecognized as susceptible to SARS-CoV-2. Across all species, lung pathology was identified post-clearance of virus shedding (antigen/RNA), with an association of virus particles within replication organelles in lung sections analysed by electron microscopy. Disrupted cell ultrastructure and lung architecture, including abnormal morphology of mitochondria 10-28 dpi, represented on-going pathophysiological consequences of SARS-CoV-2 in predominantly asymptomatic hosts. Infection kinetics and host pathology comparators using standardized methodologies enables model selection to bridge differential outcomes within upper and lower respiratory tracts and elucidate longer-term consequences of asymptomatic SARS-CoV-2 infection.


Assuntos
COVID-19 , SARS-CoV-2 , Cricetinae , Animais , Distribuição Tecidual , Administração Intranasal , Modelos Animais de Doenças , Pulmão/patologia , Mesocricetus , Macaca fascicularis
2.
Environ Entomol ; 51(5): 871-884, 2022 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-36130330

RESUMO

Landscape fire activity is changing in many regions because of climate change. Smoke emissions from landscape fires contain many harmful air pollutants, and beyond the potential hazard posed to human health, these also have ecological impacts. Insects play essential roles in most ecosystems worldwide, and some work suggests they may also be sensitive to smoke exposure. There is therefore a need for a comprehensive review of smoke impacts on insects. We systematically reviewed the scientific literature from 1930 to 2022 to synthesize the current state of knowledge of the impacts of smoke exposure from landscape fires on the development, behavior, and mortality of insects. We found: (1) 42 relevant studies that met our criteria, with 29% focused on the United States of America and 19% on Canada; (2) of these, 40 insect species were discussed, all of which were sensitive to smoke pollution; (3) most of the existing research focuses on how insect behavior responds to landscape fire smoke (LFS); (4) species react differently to smoke exposure, with for example some species being attracted to the smoke (e.g., some beetles) while others are repelled (e.g., some bees). This review consolidates the current state of knowledge on how smoke impacts insects and highlights areas that may need further investigation. This is particularly relevant since smoke impacts on insect communities will likely worsen in some areas due to increasing levels of biomass burning resulting from the joint pressures of climate change, land use change, and more intense land management involving fire.


Assuntos
Poluentes Atmosféricos , Incêndios , Humanos , Estados Unidos , Animais , Ecossistema , Poluentes Atmosféricos/análise , Mudança Climática , Insetos
3.
Histochem Cell Biol ; 158(4): 383-388, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36006466

RESUMO

Eosin Y is a common stain in histology. Although usually used for colourimetric imaging where the dye is used to stain pink/red a range of structures in the tissue, Eosin Y is also a fluorochrome, and has been used in this manner for decades. In this study our aim was to investigate the fluorescence properties of the dye to enable quantification of structures within formalin-fixed paraffin-embedded (FFPE) tissue sections. To do this, FFPE sections of hamster tissue were prepared with haematoxylin and eosin Y dyes. Spectral detection on a confocal laser scanning microscope was used to obtain the fluorescence emission spectra of the eosin Y under blue light. This showed clear spectral differences between the red blood cells and congealed blood, compared to the rest of the section. The spectra were so distinct that it was possible to discern these in fluorescence and multi-photon microscopy. An image analysis algorithm was used to quantify the red blood cells. These analyses could have broad applications in histopathology where differentiation is required, such as the analysis of clotting disorders to haemorrhage or damage from infectious disease.


Assuntos
Corantes Fluorescentes , Formaldeído , Amarelo de Eosina-(YS) , Pulmão , Microscopia Confocal , Inclusão em Parafina/métodos , Fixação de Tecidos
4.
Microbiome ; 10(1): 123, 2022 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-35945640

RESUMO

BACKGROUND: Effective standardisation of the microbiome field is essential to facilitate global translational research and increase the reproducibility of microbiome studies. In this study, we describe the development and validation of a whole cell reference reagent specific to the gut microbiome by the UK National Institute for Biological Standards and Control. We also provide and test a two-step reporting framework to allow microbiome researchers to quickly and accurately validate choices of DNA extraction, sequencing, and bioinformatic pipelines. RESULTS: Using 20 strains that are commonly found in the gut, we developed a whole cell reference reagent (WC-Gut RR) for the evaluation of the DNA extraction protocols commonly used in microbiome pipelines. DNA was first analysed using the physicochemical measures of yield, integrity, and purity, which demonstrated kits widely differed in the quality of the DNA they produced. Importantly, the combination of the WC-Gut RR and the three physicochemical measures allowed us to differentiate clearly between kit performance. We next assessed the ability of WC-Gut RR to evaluate kit performance in the reconstitution of accurate taxonomic profiles. We applied a four-measure framework consisting of Sensitivity, false-positive relative abundance (FPRA), Diversity, and Similarity as previously described for DNA reagents. Using the WC-Gut RR and these four measures, we could reliably identify the DNA extraction kits' biases when using with both 16S rRNA sequencing and shotgun sequencing. Moreover, when combining this with complementary DNA standards, we could estimate the relative bias contributions of DNA extraction kits vs bioinformatic analysis. Finally, we assessed WC-Gut RR alongside other commercially available reagents. The analysis here clearly demonstrates that reagents of lower complexity, not composed of anaerobic and hard-to-lyse strains from the gut, can artificially inflate the performance of microbiome DNA extraction kits and bioinformatic pipelines. CONCLUSIONS: We produced a complex whole cell reagent that is specific for the gut microbiome and can be used to evaluate and benchmark DNA extractions in microbiome studies. Used alongside a DNA standard, the NIBSC DNA-Gut-Mix RR helps estimating where biases occur in microbiome pipelines. In the future, we aim to establish minimum thresholds for data quality through an interlaboratory collaborative study. Video Abstract.


Assuntos
Microbiota , DNA/genética , DNA Bacteriano/genética , Fezes , Microbiota/genética , RNA Ribossômico 16S/genética , Reprodutibilidade dos Testes
5.
Eur J Sport Sci ; 22(9): 1445-1451, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34121611

RESUMO

Eating disorders (ED), disordered eating (DE) and low energy availability (LEA) can be detrimental to health and performance. Previous studies have independently investigated the prevalence of ED, DE or LEA; however, few combined methods have identified risk within female athletes. The aim of this study was to identify the prevalence of ED, DE and LEA in UK-based female athletes and investigate whether associations exist between age, competition level and primary sport. The Female Athlete Screening Tool (FAST) and Low Energy Availability in Females Questionnaire (LEAF-Q) were used in a cross-sectional study design. A total of 112 responses eligible for analysis were received. A total of 16%, 44% and 53% of female athletes were at risk of ED (FAST: >94), DE and LEA, respectively. Competition level (recreational, competitive or professional athletes; fishers, p ≤ 0.05) influenced and was a predictor of FAST (R2 = 0.076, F(1,110) = 10.067, p ≤ 0.05, variance inflation value; VIF = 1.0) whereas age influenced (age: H(2) = 13.128, p ≤ 0.05), and was a predictor (R2 = 0.144, F(2,109) = 9.170, p ≤ 0.05, VIF = 1.0) of LEAF-Q. A positive correlation was observed between FAST and LEAF-Q scores (R = 0.496, p ≤ 0.05). Age and competition level may be predicting risk factors of ED/DE and LEA within female athletes; however, further research is required to support the findings of this present study.


Assuntos
Atletas , Transtornos da Alimentação e da Ingestão de Alimentos , Estudos Transversais , Transtornos da Alimentação e da Ingestão de Alimentos/epidemiologia , Feminino , Humanos , Prevalência , Inquéritos e Questionários , Reino Unido/epidemiologia
6.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1354917

RESUMO

Introducción: La producción científica de EsSalud ha aumentado progresivamente. Sin embargo, no se ha descrito su producción científica e identificado sus redes de colaboración en las principales bases de datos bibliográficas a nivel internacional. Objetivos: Describir la producción científica de EsSalud en revistas científicas indizadas durante el periodo 2008-2020. Material y Métodos: Estudio bibliométrico que evaluó artículos científicos y resúmenes de congresos, con al menos una filiación institucional relacionada a EsSalud entre sus autores, que se encuentren indizadas en las bases de datos bibliográficas de Scopus, Web of Science, Ovid-Medline o Scielo Citation Index durante el periodo 2008-2020. Se reporta la producción científica anual total y por separado, según base. Se identificaron las redes de colaboración intra y extrainstitucionales. Resultados: Se obtuvieron 4159 registros y, tras aplicar los criterios de selección, quedaron 2333 artículos. Se observó un incremento de publicaciones en todas las bases de datos, excepto en Scielo Citation Index. La mayoría de los artículos fueron originales, observacionales y autofinanciados. Dos hospitales nacionales de EsSalud aportaron casi dos tercios de toda la producción científica evaluada. Se identifico poca colaboración entre instituciones de EsSalud de Lima con las de otras regiones y entre regiones, pero sí con las universidades locales. El área médica que más fue abordada por las publicaciones científicas fue la relacionada con las especialidades de medicina clínica. Conclusiones: La producción científica de EsSalud ha aumentado y ha mejorado en calidad, con una importante colaboración con universidades locales. Es importante impulsar iniciativas que promuevan la investigación y colaboración dentro de EsSalud, en el marco de las prioridades de investigación y de las principales causas de mayor carga de enfermedad en la institución y el país.


Background: Scientific production of Social Security in Perú (EsSalud) has progressively increased. However, there is no description of its scientific production and collaboration networks in relevant international databases. Objectives: Describe the scientific production of EsSalud in indexed journals during the 2008-2020 period. Material and Methods: Bibliometric study that evaluated scientific articles and meeting abstracts,with at least one institutional affiliation related to EsSalud among its authors, indexed in the Scopus, Web of Science, Ovid-Medline, or Scielo Citation Index databases published during the period 2008-2020. The total annual scientific production is reported and separately according to base. Intra and extra-institutional collaboration networks were evaluated. 4159 records were Results: obtained and, after applying the selection criteria, 2333 articles remained. Scientific production from all data bases, except for the Scielo Citation Index, had a progressive increase. Most of articles were original, observational, and self-funded. Two national hospitals from EsSalud accounted for almost two-thirds of all analyzed scientific production. Institutions from Lima had little collaboration with other institutions from other regions, leading to little interregional collaboration. On the other side, there was a noticeable collaboration with local universities. The medical area that was most addressed by scientific publications was that related to clinical medicine specialties. EsSalud's Conclusions:scientific production number and quality had increased during last years in collaboration with local universities.It is important to promote initiatives thar boost the research and collaboration within EsSalud's institutions,emphasizing research priorities and the leading causes of national morbidity and mortality.

8.
Sci Rep ; 10(1): 21774, 2020 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-33311596

RESUMO

Tuberculosis (TB) preclinical testing relies on in vivo models including the mouse aerosol challenge model. The only method of determining colony morphometrics of TB infection in a tissue in situ is two-dimensional (2D) histopathology. 2D measurements consider heterogeneity within a single observable section but not above and below, which could contain critical information. Here we describe a novel approach, using optical clearing and a novel staining procedure with confocal microscopy and mesoscopy, for three-dimensional (3D) measurement of TB infection within lesions at sub-cellular resolution over a large field of view. We show TB morphometrics can be determined within lesion pathology, and differences in infection with different strains of Mycobacterium tuberculosis. Mesoscopy combined with the novel CUBIC Acid-Fast (CAF) staining procedure enables a quantitative approach to measure TB infection and allows 3D analysis of infection, providing a framework which could be used in the analysis of TB infection in situ.


Assuntos
Microscopia/métodos , Coloração e Rotulagem/métodos , Tuberculose/diagnóstico por imagem , Animais , Modelos Animais de Doenças , Humanos , Camundongos , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose/microbiologia , Tuberculose/patologia
9.
Sci Rep ; 10(1): 11694, 2020 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-32678135

RESUMO

Neutrophils are pivotal players in immune defence which includes a process of release of histones and DNA as neutrophil extracellular traps (NETs). Histones, while toxic to invading pathogens, also kill host cells, including neutrophils. Bacteria have evolved mechanisms to escape neutrophils, including the secretion of leucocidins (e.g. ionomycin). Live cell video microscopy showed how fibrinogen and fibrin influence NETosis and neutrophil responses to extracellular histones. Histones were rapidly lethal to neutrophils after binding to cells, but formation of fibrinogen/fibrin-histone aggregates prevented cell death. Histone cytotoxicity was also reduced by citrullination by peptidyl arginine deiminase 4, or digestion by serine proteases. Ionomycin and phorbol 12-myristate 13 acetate (PMA) are used to trigger NETosis. Fibrinogen was responsible for a second distinct mechanism of neutrophil protection after treatment with ionomycin. Fibrinogen clustered on the surface of ionomycin-stimulated neutrophils to delay NETosis; and blocking the ß integrin receptor, αMß2, abolished fibrinogen protection. Fibrinogen did not bind to or protect neutrophils stimulated with PMA. Fibrinogen is an acute phase protein that will protect exposed cells from damaging circulating histones or leucocidins; but fibrinogen depletion/consumption, as in trauma or sepsis will reduce protection. It is necessary to consider the role of fibrinogen in NETosis.


Assuntos
Armadilhas Extracelulares/efeitos dos fármacos , Produtos de Degradação da Fibrina e do Fibrinogênio/farmacologia , Histonas/farmacologia , Ionomicina/farmacologia , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Substâncias Protetoras/farmacologia , Doadores de Sangue , Morte Celular/efeitos dos fármacos , Células Cultivadas , Citrulinação , DNA/metabolismo , Armadilhas Extracelulares/metabolismo , Produtos de Degradação da Fibrina e do Fibrinogênio/metabolismo , Histonas/metabolismo , Humanos , Antígeno de Macrófago 1/metabolismo , Agregados Proteicos , Acetato de Tetradecanoilforbol/farmacologia
10.
Rev. méd. hered ; 31(2): 116-118, abr.-jun 2020. graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1144825

RESUMO

Resumen El aneurisma del seno de Valsalva es una entidad poco frecuente, con una incidencia de 0,09 a 0,15%, en algunos casos los pacientes se presentan asintomáticos siempre que el aneurisma se encuentre íntegro. Si se perfora, se manifiesta como un cuadro de insuficiencia cardiaca rápidamente progresiva. Comunicamos el caso de una paciente de 27 años sin comorbilidades, con rotura del aneurisma del seno de Valsalva y se realiza una revisión bibliográfica del tema.


Summary Sinus of Valsalva aneurysm is a rare entity, with an incidence of 0.09-0.15%. In some cases, patients with aneurysm show up asymptomatic whenever the aneurysm is intact. If it is perforated, it manifests itself as a rapidly progressive heart failure chart. We report the case of a 27-year-old patient without comorbidities with rupture of the aneurysm of the Valsalva sinus and carry out a bibliographic review.

12.
Mol Ther Methods Clin Dev ; 16: 161-171, 2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32055644

RESUMO

Recent clinical trials are evaluating induced pluripotent stem cells (iPSCs) as a cellular therapy in the field of regenerative medicine. The widespread clinical utility of iPSCs is expected to be realized using allogeneic cells that have undergone thorough safety evaluations, including assessment of their immunogenicity. IPSC-derived neural crest stem cells (NCSCs) have significant potential in regenerative medicine; however, their application in cellular therapy has not been widely studied to date, and no reports on their potential immunogenicity have been published so far. In this study, we have assessed the expression of immune-related antigens in iPSC-NCSCs, including human leukocyte antigen (HLA) class I and II and co-stimulatory molecules. To investigate functional immunogenicity, we used iPSC-NCSCs as stimulator cells in a one-way mixed lymphocyte reaction. In these experiments, iPSC-NCSCs did not stimulate detectable proliferation of CD3+ and CD3+CD8+ T cells or induce cytokine production. We show that this was not a result of any immunosuppressive features of iPSC-NCSCs, but rather more consistent with their non-immunogenic molecular phenotype. These results are encouraging for the potential future use of iPSC-NCSCs as a cellular therapy.

13.
Vaccine ; 38(13): 2859-2869, 2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-32089463

RESUMO

To examine the link between meningococcal C (MenC) vaccine size and immunogenic response, a panel of MenC glycoconjugate vaccines were prepared differing in chain length, molar mass and hydrodynamic volume. The preparations consisted of different lengths of MenC polysaccharide (PS) covalently linked to monomeric purified tetanus toxoid (TT) carrier protein using the coupling reagent ethylcarbodiimide hydrochloride (EDC). Size exclusion chromatography with multi-angle light scattering (SEC-MALS) and viscometry analysis confirmed that the panel of MenC-TT conjugates spanned masses of 191,500 to 2,348,000 g/mol, and hydrodynamic radii ranging from 12.1 to 47.9 nm. The two largest conjugates were elliptical in shape, whereas the two smallest conjugates were more spherical. The larger conjugates appeared to fit a model described by multiple TTs with cross-linked PS, typical of lattice-like networks described previously for TT conjugates, while the smaller conjugates were found to fit a monomeric or dimeric TT configuration. The effect of vaccine conjugate size on immune responses was determined using a two-dose murine immunization. The two larger panel vaccine conjugates produced higher anti-MenC IgG1 and IgG2b titres after the second dose. Larger vaccine conjugate size also stimulated greater T-cell proliferative responses in an in vitro recall assay, although cytokines indicative of a T-helper response were not measurable. In conclusion, larger MenC-TT conjugates up to 2,348,000 g/mol produced by EDC chemistry correlate with greater humoral and cellular murine immune responses. These observations suggest that conjugate size can be an important modulator of immune response.


Assuntos
Carbodi-Imidas , Imunogenicidade da Vacina , Vacinas Meningocócicas/imunologia , Neisseria meningitidis Sorogrupo C , Toxoide Tetânico/imunologia , Animais , Anticorpos Antibacterianos , Imunoconjugados/imunologia , Camundongos , Neisseria meningitidis Sorogrupo C/imunologia , Polissacarídeos Bacterianos/imunologia , Vacinas Combinadas , Vacinas Conjugadas
15.
Environ Monit Assess ; 191(10): 618, 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31493019

RESUMO

Legal and policy initiatives to address the environmental dimensions of armed conflicts and their impact on people, ecosystems and sustainable development are highly dependent on the availability of environmental data from conflict-affected areas. Socio-political and security conditions in these areas often impede data collection, while traditional models of post-conflict environmental assessments are limited in scope. In response, an increasing range of actors is utilising remote sensing and open source data collection to identify and estimate health and ecological risks during and after conflicts. This paper considers the role of participatory citizen science methodologies in complementing both remote monitoring and post-conflict assessments. It examines existing models and mechanisms for environmental data collection and utilisation in conflict contexts, and the extent to which the core values and principles of citizen science are transferable. We find that 'civilian science' is feasible and could be well-suited to conflict conditions. In addition to addressing gaps in data collection, it may also empower communities affected by environmental degradation, enhance their environmental human rights, supplement the often limited monitoring capacity of governmental agencies and facilitate cooperation and peacebuilding. The paper concludes by proposing methodological approaches for three common forms of environmental degradation associated with armed conflicts.


Assuntos
Conflitos Armados , Participação da Comunidade , Monitoramento Ambiental/métodos , Coleta de Dados , Ecossistema , Humanos , Desenvolvimento Sustentável
16.
Sci Total Environ ; 670: 411-424, 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-30909028

RESUMO

Cities are dependent on their upstream watersheds for storage and gradual release of water into river systems. These watersheds act as important flood mitigation infrastructure, providing an essential ecosystem service. In this paper we use metrics from the WaterWorld model to examine the flood management-relevant natural infrastructure of the upstream watersheds of selected global cities. These metrics enable the characterisation of different types, magnitudes and geographical distributions of potential natural flood storage. The storages are categorised as either green (forest canopy, wetland and soil) or blue (water body and floodplain) storages and the proportion of green to blue indicates how different city upstream basin contexts provide different types and levels of storage which may buffer flood risk. We apply the WaterWorld method for examining flood risk as the ratio of accumulated modelled annual runoff volume to accumulated available green and blue water storage capacity. The aim of these metrics is to highlight areas where there is more runoff than storage capacity and thus where the maintenance or restoration of further natural infrastructure (such as canopy cover, wetlands and soil) could aid in storing more water and thus better alleviate flood risks. Such information is needed by urban planners, city authorities and governments to help prepare cities for climate change impacts.

17.
J Fam Theory Rev ; 11(1): 79-91, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37309504

RESUMO

U.S. children are more likely to live apart from a biological parent than at any time in history. Although the Child Support Enforcement system has tremendous reach, its policies have not kept pace with significant economic, demographic, and cultural changes. Narrative analysis of in-depth interviews with 429 low-income noncustodial fathers suggests that the system faces a crisis of legitimacy. Visualization of language used to describe all forms child support show that the formal system is considered punitive and to lead to a loss of power and autonomy. Further, it is not associated with coparenting or the father-child bond-themes closely associated with informal and in-kind support. Rather than stoking men's identities as providers, the system becomes "just another bill to pay." Orders must be sustainable, all fathers should have coparenting agreements, and alternative forms of support should count toward fathers' obligations. Recovery of government welfare costs should be eliminated.

18.
Sci Rep ; 8(1): 11927, 2018 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-30093682

RESUMO

Alveolar type II (ATII) cells play a key role as part of the distal lung epithelium, including roles in the innate immune response and as self-renewing progenitors to replace alveolar type I (ATI) cells during regeneration of the alveolar epithelium. Their secretion of surfactant protein helps to maintain homeostasis in the distal lung and exert protective, antimicrobial properties. Despite the cell's crucial roles, they remain difficult to study, in part due to inefficient and expensive isolation methods, a propensity to differentiate into alveolar type I cells in culture and susceptibility to fibroblast overgrowth from primary isolations. Published methods of isolation often require specialist technology, negatively impacting the development of in vitro models of disease, including bovine tuberculosis (BTB), a serious re-emerging disease in both animals and humans worldwide. We present here a simple and cost-effective method that may be utilised in the generation of bovine primary ATII cells. These exhibit an ATII phenotype in 2D and 3D culture in our studies and are conducive to further study of the role of ATII cells in bovine respiratory diseases.


Assuntos
Células Epiteliais Alveolares/citologia , Técnicas de Cultura de Células/métodos , Transdiferenciação Celular , Pulmão/citologia , Alvéolos Pulmonares/citologia , Células Epiteliais Alveolares/metabolismo , Animais , Bovinos , Autorrenovação Celular , Células Cultivadas , Humanos , Alvéolos Pulmonares/metabolismo , Surfactantes Pulmonares/metabolismo
19.
Virulence ; 8(8): 1820-1832, 2017 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-28892415

RESUMO

An important feature of Mycobacterium tuberculosis pathogenesis is the ability to control cell death in infected host cells, including inhibition of apoptosis and stimulation of necrosis. Recently an alternative form of programmed cell death, necroptosis, has been described where necrotic cell death is induced by apoptotic stimuli under conditions where apoptotic execution is inhibited. We show for the first time that M. tuberculosis and TNFα synergise to induce necroptosis in murine fibroblasts via RIPK1-dependent mechanisms and characterized by phosphorylation of Ser345 of the MLKL necroptosis death effector. However, in murine macrophages M. tuberculosis and TNFα induce non-necroptotic cell death that is RIPK1-dependent but independent of MLKL phosphorylation. Instead, M. tuberculosis-infected macrophages undergo RIPK3-dependent cell death which occurs both in the presence and absence of TNFα and involves the production of mitochondrial ROS. Immunocytochemical staining for MLKL phosphorylation further demonstrated the occurrence of necroptosis in vivo in murine M. tuberculosis granulomas. Phosphorylated-MLKL immunoreactivity was observed associated with the cytoplasm and nucleus of fusiform cells in M. tuberculosis lesions but not in proximal macrophages. Thus whereas pMLKL-driven necroptosis does not appear to be a feature of M. tuberculosis-infected macrophage cell death, it may contribute to TNFα-induced cytotoxicity of the lung stroma and therefore contribute to necrotic cavitation and bacterial dissemination.


Assuntos
Apoptose , Mycobacterium tuberculosis/fisiologia , Proteínas Quinases/imunologia , Tuberculose/microbiologia , Fator de Necrose Tumoral alfa/imunologia , Animais , Feminino , Humanos , Macrófagos/imunologia , Macrófagos/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Mycobacterium tuberculosis/genética , Necrose , Fosforilação , Proteínas Quinases/genética , Especificidade da Espécie , Tuberculose/imunologia , Tuberculose/fisiopatologia , Fator de Necrose Tumoral alfa/genética
20.
Acad Radiol ; 24(9): 1114-1124, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28365232

RESUMO

RATIONALE AND OBJECTIVES: To compare adaptive statistical iterative reconstruction (ASIR) and model-based iterative reconstruction (MBIR) algorithms for reduced-dose computed tomography (CT). MATERIALS AND METHODS: Forty-four young oncology patients (mean age 30 ± 9 years) were included. After routine thoraco-abdominal CT (dose 100%, average CTDIvol 9.1 ± 2.4 mGy, range 4.4-16.9 mGy), follow-up CT was acquired at 50% (average CTDIvol 4.5 ± 1.2 mGy, range 2.2-8.4 mGy) in 29 patients additionally at 20% dose (average CTDIvol 1.9 ± 0.5 mGy, range 0.9-3.4 mGy). Each reduced-dose CT was reconstructed using both ASIR and MBIR. Four radiologists (two juniors and two seniors) blinded to dose and technique read each set of CT images regarding objective and subjective image qualities (high- or low-contrast structures), subjective noise or pixilated appearance, diagnostic confidence, and lesion detection. RESULTS: At all dose levels, objective image noise was significantly lower with MBIR than with ASIR (P < 0.001). The subjective image quality for low-contrast structures was significantly higher with MBIR than with ASIR (P < 0.001). Reduced-dose abdominal CT images of patients with higher body mass index (BMI) were read with significantly higher diagnostic confidence than images of slimmer patients (P < 0.001) and had higher subjective image quality, regardless of technique. Although MBIR images appeared significantly more pixilated than ASIR images, they were read with higher diagnostic confidence, especially by juniors (P < 0.001). CONCLUSIONS: Reduced-dose CT during the follow-up of young oncology patients should be reconstructed with MBIR to ensure diagnostic quality. Elevated body mass index does not hamper the quality of reduced-dose CT.


Assuntos
Algoritmos , Processamento de Imagem Assistida por Computador/métodos , Neoplasias/diagnóstico por imagem , Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Adolescente , Adulto , Índice de Massa Corporal , Feminino , Humanos , Masculino , Exposição à Radiação , Razão Sinal-Ruído , Método Simples-Cego , Adulto Jovem
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