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1.
Front Microbiol ; 15: 1367658, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38737410

RESUMEN

Introduction: Nitrososphaeria, formerly known as Thaumarchaeota, constitute a diverse and widespread group of ammonia-oxidizing archaea (AOA) inhabiting ubiquitously in marine and terrestrial environments, playing a pivotal role in global nitrogen cycling. Despite their importance in Earth's ecosystems, the cellular organization of AOA remains largely unexplored, leading to a significant unanswered question of how the machinery of these organisms underpins metabolic functions. Methods: In this study, we combined spherical-chromatic-aberration-corrected cryo-electron tomography (cryo-ET), scanning transmission electron microscopy (STEM), and energy dispersive X-ray spectroscopy (EDS) to unveil the cellular organization and elemental composition of Nitrosopumilus maritimus SCM1, a representative member of marine Nitrososphaeria. Results and Discussion: Our tomograms show the native ultrastructural morphology of SCM1 and one to several dense storage granules in the cytoplasm. STEM-EDS analysis identifies two types of storage granules: one type is possibly composed of polyphosphate and the other polyhydroxyalkanoate. With precise measurements using cryo-ET, we observed low quantity and density of ribosomes in SCM1 cells, which are in alignment with the documented slow growth of AOA in laboratory cultures. Collectively, these findings provide visual evidence supporting the resilience of AOA in the vast oligotrophic marine environment.

2.
bioRxiv ; 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38645020

RESUMEN

Calcium imaging has become an increasingly popular way to probe the activity of astrocytes. However, the governing principles of astrocyte calcium dynamics are still elusive and their relationship to cellular events ill-defined. Useful assumptions and 'shortcuts' commonly applied to neuronal recordings therefore do not hold true for astrocytes. The imaging of astrocyte calcium activity per se can be relatively straightforward, subsequent analysis methods that adequately capture the richness and complexity of calcium dynamics remain scant. Here, we introduce STARDUST, a pipeline and python-based data processing for the Spatio-Temporal Analysis of Regional Dynamics & Unbiased Sorting of Transients from astrocyte calcium recordings. STARDUST builds upon AQuA to identify patches of active signals, from which it builds a data-driven map of regions of activity (ROAs) that can be combined with cell-segmentation and/or correlated to cellular morphology. For each ROA, STARDUST extracts fluorescence time-series, and performs signal identification and features extraction. STARDUST is agnostic to cell morphology (or cells altogether) and putative calcium propagation across ROAs. Instead, it focuses on decomposing calcium dynamics in a regionalized fashion by treating ROAs as independent units, for instance allowing investigations by signal feature-based ROA rank. STARDUST also identifies ROAs as "stable" (active throughout), "ON" (turned on during drug application) and "OFF" (turned off during drug application) in pharmacology experiments, permitting studies of astrocyte calcium "micro-domains" based on their functional responses. With a systematic set of instructions and troubleshooting tips, and minimal computational/coding background required, STARDUST is a user-friendly addition to the growing toolbox for the exploration of astrocyte calcium dynamics.

3.
Infect Drug Resist ; 16: 7377-7387, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38053579

RESUMEN

Background: For the distinct immune/inflammatory responses from Omicron variant infection, this study aimed to investigate the diagnostic efficacy of systemic inflammatory indicators and the clinical efficacy of corticosteroids on the in-hospital mortality among COVID-19 patients. Methods: Under a retrospective cohort study, 1081 COVID-19 patients were recruited from Beijing Youan Hospital, Capital Medical University between November 16, 2022 and January 30, 2023. We chose neutrophil-to-lymphocyte ratio (NLR), CRP-to-lymphocyte ratio (CLR), and CRP-to-albumin ratio (CAR) as the systemic inflammatory indicators. Receiver operating curve (ROC) and multivariate logistic regression analysis were used to determine the diagnostic efficacy of systemic inflammatory indicators and the association between systemic inflammatory indicators and in-hospital mortality. Results: Among 684 patients included in analysis, 96 died during hospitalization. NLR, CLR and CAR performed well (with an area under the curve (AUC) greater than 0.75) in discriminating in-hospital mortality among COVID-19 patients. The severe status of systemic inflammation, with optimal cut-off value derived from ROC analysis, significantly associated higher risk of in-hospital mortality (OR = 3.81 for NLR ≥ 6.131; OR = 3.76 for CLR ≥ 45.455; OR = 5.10 for CAR ≥ 1.436). Corticosteroids use within 72 hours of admission increased the in-hospital mortality 2.88-fold for COVID-19 patients. In the subgroup of patients with severe systemic inflammation, corticosteroids increased the risk of in-hospital mortality (OR = 2.11 for NLR, p = 0.055; OR = 2.94 for CLR, p = 0.005; OR = 2.31 for CAR, p = 0.036). Conclusion: Systemic inflammatory indicators had good diagnostic performance for in-hospital mortality. Patients with severe systemic inflammatory status should not receive corticosteroid treatment and further studies are warranted for confirmation.

4.
Artículo en Inglés | MEDLINE | ID: mdl-32582575

RESUMEN

Background: A novel enveloped RNA beta coronavirus, Corona Virus Disease 2019 (COVID-19) caused severe and even fetal pneumonia in China and other countries from December 2019. Early detection of severe patients with COVID-19 is of great significance to shorten the disease course and reduce mortality. Methods: We assembled a retrospective cohort of 80 patients (including 56 mild and 24 severe) with COVID-19 infection treated at Beijing You'an Hospital. We used univariable and multivariable logistic regression analyses to select the risk factors of severe and even fetal pneumonia and build scoring system for prediction, which was validated later on in a group of 22 COVID-19 patients. Results: Age, white blood cell count, neutrophil, glomerular filtration rate, and myoglobin were selected by multivariate analysis as candidates of scoring system for prediction of disease severity in COVID-19. The scoring system was applied to calculate the predictive value and found that the percentage of ICU admission (20%, 6/30) and ventilation (16.7%, 5/30) in patients with high risk was much higher than those (2%, 1/50; 2%, 1/50) in patients with low risk (p = 0.009; p = 0.026). The AUC of scoring system was 0.906, sensitivity of prediction is 70.8%, and the specificity is 89.3%. According to scoring system, the probability of patients in high risk group developing severe disease was 20.24 times than that in low risk group. Conclusions: The possibility of severity in COVID-19 infection predicted by scoring system could help patients to receiving different therapy strategies at a very early stage. Topic: COVID-19, severe and fetal pneumonia, logistic regression, scoring system, prediction.


Asunto(s)
Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/patología , Neumonía Viral/epidemiología , Neumonía Viral/patología , Índice de Severidad de la Enfermedad , Anciano , Anciano de 80 o más Años , Betacoronavirus/patogenicidad , COVID-19 , China , Comorbilidad , Progresión de la Enfermedad , Femenino , Tasa de Filtración Glomerular/fisiología , Humanos , Recuento de Leucocitos , Masculino , Persona de Mediana Edad , Mioglobina/análisis , Infiltración Neutrófila/inmunología , Neutrófilos/inmunología , Pandemias , Pronóstico , Estudios Retrospectivos , SARS-CoV-2
5.
JCI Insight ; 5(13)2020 07 09.
Artículo en Inglés | MEDLINE | ID: mdl-32501293

RESUMEN

BACKGROUND: Identifying immune correlates of COVID-19 disease severity is an urgent need for clinical management, vaccine evaluation, and drug development. Here, we present a temporal analysis of key immune mediators, cytokines, and chemokines in blood of hospitalized COVID-19 patients from serial sampling and follow-up over 4 weeks. METHODS: A total of 71 patients with laboratory-confirmed COVID-19 admitted to Beijing You'an Hospital in China with either mild (53 patients) or severe (18 patients) disease were enrolled with 18 healthy volunteers. We measured 34 immune mediators, cytokines, and chemokines in peripheral blood every 4-7 days over 1 month per patient using a bioplex multiplex immunoassay. RESULTS: We found that the chemokine RANTES (CCL5) was significantly elevated, from an early stage of the infection, in patients with mild but not severe disease. We also found that early production of inhibitory mediators including IL-10 and IL-1RA were significantly associated with disease severity, and a combination of CCL5, IL-1 receptor antagonist (IL-1RA), and IL-10 at week 1 may predict patient outcomes. The majority of cytokines that are known to be associated with the cytokine storm in virus infections such as IL-6 and IFN-γ were only significantly elevated in the late stage of severe COVID-19 illness. TNF-α and GM-CSF showed no significant differences between severe and mild cases. CONCLUSION: Together, our data suggest that early intervention to increase expression of CCL5 may prevent patients from developing severe illness. Our data also suggest that measurement of levels of CCL5, as well as IL-1RA and IL-10 in blood individually and in combination, might be useful prognostic biomarkers to guide treatment strategies.


Asunto(s)
Quimiocina CCL5/inmunología , Infecciones por Coronavirus/inmunología , Proteína Antagonista del Receptor de Interleucina 1/inmunología , Interleucina-10/inmunología , Neumonía Viral/inmunología , Adulto , Anciano , Betacoronavirus , COVID-19 , Estudios de Casos y Controles , Infecciones por Coronavirus/fisiopatología , Síndrome de Liberación de Citoquinas/inmunología , Femenino , Factor Estimulante de Colonias de Granulocitos y Macrófagos/inmunología , Hospitalización , Humanos , Inmunoensayo , Interferón gamma/inmunología , Interleucina-6/inmunología , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Pandemias , Neumonía Viral/fisiopatología , SARS-CoV-2 , Índice de Severidad de la Enfermedad , Factor de Necrosis Tumoral alfa/inmunología
6.
J Infect Dis ; 222(1): 34-37, 2020 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-32348495

RESUMEN

A major unanswered question in the current global coronavirus disease 2019 (COVID-19) outbreak is why severe disease develops in a small minority of infected individuals. In the current article, we report that homozygosity for the C allele of rs12252 in the interferon-induced transmembrane protein 3 (IFITM3) gene is associated with more severe disease in an age-dependent manner. This supports a role for IFITM3 in disease pathogenesis and the opportunity for early targeted intervention in at-risk individuals.


Asunto(s)
Alelos , Betacoronavirus/genética , Infecciones por Coronavirus/genética , Proteínas de la Membrana/genética , Neumonía Viral/genética , Polimorfismo de Nucleótido Simple , Proteínas de Unión al ARN/genética , Índice de Severidad de la Enfermedad , Adulto , Anciano , Anciano de 80 o más Años , COVID-19 , Estudios de Cohortes , Infecciones por Coronavirus/virología , Femenino , Genotipo , Secuenciación de Nucleótidos de Alto Rendimiento , Homocigoto , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Pandemias , Neumonía Viral/virología , Reacción en Cadena en Tiempo Real de la Polimerasa , SARS-CoV-2
7.
IUCrJ ; 6(Pt 3): 366-372, 2019 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-31098018

RESUMEN

Stress-induced martensitic detwinning and martensitic transformation during step-wise compression in an austenite Ni-Mn-Ga matrix with a martensite cluster under uniaxial loading have been investigated by electron backscatter diffraction, focusing on the crystallographic features of microstructure evolution. The results indicate that detwinning occurs on twins with a high Schmid factor for both intra-plate and inter-plate twins in the hierarchical structure, resulting in a nonmodulated (NM) martensite composed only of favourable variants with [001]NM orientation away from the compression axis. Moreover, the stress-induced martensitic transformation occurs at higher stress levels, undergoing a three-stage transformation from austenite to a twin variant pair and finally to a single variant with increasing compressive stress, and theoretical calculation shows that the corresponding crystallographic configuration is accommodated to the compression stress. The present research not only provides a comprehensive understanding of martensitic variant detwinning and martensitic transformation under compression stress, but also offers important guidelines for the mechanical training process of martensite.

8.
Artículo en Inglés | MEDLINE | ID: mdl-29868492

RESUMEN

Background: The C allele of the interferon-induced transmembrane protein-3 (IFITM3) SNP rs12252, a common allele in South East Asia and China, is strongly associated with severe influenza infection. However, despite the high occurrence of rs12252-CC genotype in Chinese population (~25%), severe influenza infection is rare. The aim of study is to determine whether rs12252-CC individuals have pre-existing antibody responses to previous seasonal influenza infections. Cohort and Method: A total 99 young healthy volunteers (18-20 years) were recruited and received an influenza seasonal Vaccination [A/Switzerland/9715293/2013(H3N2), A/California/7/2009 (pdm09H1N1) and B/Jeep/3073/2013-like virus (Flu-B)]. Plasma and gDNA was isolated from each volunteer before, and 14, 28, 180, 360, and 540 days after vaccination. Additionally, 68 elderlies (>65 years) were also recruited as a control group to compare the levels of antibodies at baseline between the young adults and the elderly. For each sample IFITM3 rs12252 genotype was determined and antibody levels in response to pdmH1N1, H3N2 and Influenza B infection were measured for each time point. Results: We found a significantly higher level of pre-existing antibodies to pandemic influenza H1N1/09 virus (pdm09H1N1) but not to H3N2 or FluB in CC donors in comparison with CT/TT donors prior to vaccination. No impact of IFITM3 genotype in boosting influenza specific antibodies in young adults within 1 year after receiving seasonal influenza vaccination was observed. In addition, there was no difference in pdm09H1N1 specific antibody levels observed in the elderly cohort between volunteers carrying different IFITM3 genotypes. Higher levels of antibodies to pdmH1N1 were observed in elderly CC carriers when compared to the young CC carriers, but this trend was not replicated in TT carriers. Conclusion:IFITM3-rs12252 CC carriers exhibit a high level of pre-existing immunity to pdm09H1N1 compared to TT carriers in the young cohort. This suggests that compensatory mechanisms exist which might contribute to viral control in patients carrying the rs12252-CC genotype who do not become sick after flu infection. However, such a potential compensatory effect appears to be lost overtime, as evidenced in the elderly cohort. If this compensatory mechanism is lost, it may make the CC carrying elderly more susceptible to severe influenza infection.


Asunto(s)
Anticuerpos Antivirales/inmunología , Subtipo H1N1 del Virus de la Influenza A/inmunología , Gripe Humana/inmunología , Proteínas de la Membrana/genética , Proteínas de Unión al ARN/genética , Vacunación , Adolescente , Anciano , Anciano de 80 o más Años , Alelos , Anticuerpos Antivirales/sangre , China , Estudios de Cohortes , Citocinas/sangre , Citocinas/inmunología , Femenino , Genotipo , Humanos , Subtipo H1N1 del Virus de la Influenza A/genética , Gripe Humana/sangre , Gripe Humana/prevención & control , Gripe Humana/virología , Masculino , Proteínas de la Membrana/metabolismo , Proteínas de Unión al ARN/metabolismo , Adulto Joven
9.
Int J Infect Dis ; 59: 37-43, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28342803

RESUMEN

As antiretroviral therapy provides long term viral suppression but no cure, alternative therapies such as adoptive cellular therapy have thus been investigated in the anti-AIDS field. OBJECTIVE: This study sought to establish a HLA-A02 specific CTL cell culture method with comparison of the effects of different cytokines used in CTL cultivation to decide the best cultivation environment. In order to produce CTLs with targeted HLA-A02 restricted antigen specificity for adoptive cellular therapy, we evaluated autologous PBMC cultivation in different cytokine environment to select a better expansion condition to produce qualified CTL production. METHODS: We co-cultivated PBMC and peptides of these patients with HLA-A02 allele with different cytokines. After cultivation, multiple parameters were tested. RESULTS: 1) Cytokines IL-2 alone can effectively amplify HLA-A02 specific CTL cells, and the count of CTLs was >85% all through the process. 2) The HLA-A02 specific cells at the end of the cultivation were mainly CD3+CD8+ cells. 3) The interferon stimulation test had shown that the expanded CTLs secreted more IFN-γ than before cultivation (0.9% -11.70%). CONCLUSION: This model of CTL cultivation is successful in redirecting the specificity of antigen recognition and safely for HLA-A02+ patients cell adoptive therapy.


Asunto(s)
Inmunoterapia Adoptiva/métodos , Linfocitos T Citotóxicos/inmunología , Adulto , Alelos , Células Cultivadas , Citocinas/inmunología , Femenino , Antígeno HLA-A2/inmunología , Humanos , Leucocitos Mononucleares/inmunología , Masculino , Persona de Mediana Edad
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