RESUMEN
Biological nitrogen fixation catalyzed by nitrogenase contributes greatly to the global nitrogen cycle. Nitrogenase expression is subject to regulation in response to nitrogen availability. However, the mechanism through which the transcriptional activator NifA regulates nitrogenase expression by interacting with PII nitrogen regulatory proteins remains unclear in diazotrophic proteobacteria lacking NifL. Here, we demonstrate that in Rhodopseudomonas palustris grown with ammonium, NifA bound deuridylylated PII proteins to form an inactive NifA-PII complex, thereby inhibiting the expression of nitrogenase. Upon nitrogen limitation, the dissociation of uridylylated PII proteins from NifA resulted in the full restoration of NifA activity, and, simultaneously, uridylylation of the significantly up-regulated PII protein GlnK2 led to the increased expression of NifA in R. palustris. This insight into how NifA interacts with PII proteins and controls nitrogenase expression sets the stage for creating highly efficient diazotrophs, reducing the need for energy-intensive chemical fertilizers and helping to diminish carbon emissions.
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Compuestos de Amonio , Proteínas Bacterianas , Fijación del Nitrógeno , Proteínas PII Reguladoras del Nitrógeno , Factores de Transcripción , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Compuestos de Amonio/metabolismo , Proteínas PII Reguladoras del Nitrógeno/metabolismo , Proteínas PII Reguladoras del Nitrógeno/genética , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Regulación Bacteriana de la Expresión Génica , Nitrogenasa/metabolismo , Rhodopseudomonas/metabolismo , Rhodopseudomonas/genéticaRESUMEN
Photosynthetic diazotrophs expressing iron-only (Fe-only) nitrogenase can be developed into a promising biofertilizer, as it is independent on the molybdenum availability in the soil. However, the expression of Fe-only nitrogenase in diazotrophs is repressed by the fixed nitrogen of the soil, limiting the efficiency of nitrogen fixation in farmland with low ammonium concentrations that are inadequate for sustainable crop growth. Here, we succeeded in constitutively expressing the Fe-only nitrogenase even in the presence of ammonium by controlling the transcription of Fe-only nitrogenase gene cluster (anfHDGK) with the transcriptional activator of Mo nitrogenase (NifA*) in several different ways, indicating that the engineered NifA* strains can be used as promising chassis cells for efficient expression of different types of nitrogenases. When applied as a biofertilizer, the engineered Rhodopseudomonas palustris effectively stimulated rice growth, contributing to the reduced use of chemical fertilizer and the development of sustainable agriculture.
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Compuestos de Amonio , Oryza , Fijación del Nitrógeno , Nitrogenasa/genética , Nitrogenasa/metabolismo , Nitrógeno/metabolismo , SueloRESUMEN
Hepatic ischemia-reperfusion injury (HIRI) adversely affects liver transplant and resection outcomes. Recently, ferroptosis has been associated with HIRI. Dexmedetomidine (Dex), a potent sedative with anti-inflammatory, antioxidant, and anti-apoptotic properties, protects organs from hypoxic or ischemia-reperfusion (I/R) injuries. However, the mechanisms underlying this protective effect against I/R-induced liver injury remain unclear. This study evaluated the effect of Dex on HIRI in mouse models and the oxygen-glucose deprivation/reperfusion (OGD/R) AML12 cell model. We examined ferroptosis-related markers, including Fe2+ levels, reactive oxygen species (ROS) content, mitochondrial morphology, GPX4 protein expression, 4-hydroxynonenal (4-HNE), and Nrf2. The Nrf2 inhibitor ML385 was used in combination with Dex to treat HIRI mice and OGD/R-induced cellular models to explore the pathways by which Dex counteracts ferroptosis. Our results showed that Dex treatment significantly ameliorated OGD/R-induced ferroptosis in AML12 cells, including reduced Fe2+, ROS, malondialdehyde (MDA), and 4-HNE levels. Dex also ameliorated liver tissue damage and reduced serum AST, ALT, and inflammatory factor levels in HIRI mice. Additionally, Dex increased the levels of GSH, an antioxidative stress marker, and GPX4 expression in HIRI mice. Mechanistically, Nrf2 expression and nuclear translocation were significantly inhibited in both HIRI mice and OGD/R-treated AML12 cells. Dex treatment also restored the I/R-induced inhibition of Nrf2 expression and nuclear translocation. ML385 significantly inhibited Dex-promoted Nrf2 nuclear aggregation with Gpx4 protein expression, hindering the efficacy of Dex. In conclusion, Dex ameliorates ferroptosis in HIRI by positively regulating the Nrf2/GPx4 axis, potentially presenting a therapeutic avenue for addressing HIRI.
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Dexmedetomidina , Ferroptosis , Daño por Reperfusión , Animales , Ratones , Antioxidantes/farmacología , Dexmedetomidina/farmacología , Dexmedetomidina/uso terapéutico , Factor 2 Relacionado con NF-E2 , Especies Reactivas de Oxígeno , Hígado , Daño por Reperfusión/tratamiento farmacológicoRESUMEN
AIM: The kynurenine pathway is increasingly recognised to play a role in inflammation and disease. We assessed the cross-sectional and longitudinal associations of adiposity measures (body mass index, waist-hip ratio, waist circumference and fat mass ratio) with plasma concentrations of kynurenine pathway metabolites and traditional markers of inflammation. METHODS: We used data from 970 Melbourne Collaborative Cohort Study participants who had plasma markers measured at baseline (median age 59 years) and follow-up (median age 70 years). Linear regression was used to assess cross-sectional and longitudinal associations between four adiposity measures and concentrations of i) nine kynurenine pathway metabolites; ii) two derived markers; iii) eight traditional inflammatory markers. RESULTS: Cross-sectionally, most kynurenine metabolites were strongly associated with adiposity measures at both time points; associations were generally stronger than for most inflammation markers except CRP (e.g. body mass index at baseline, quinolinic acid (per S.D. ß = 0.30, 95%CI: 0.24-0.36, P = 10-21), kynurenine (ß = 0.25, 95%CI: 0.19-0.31, P = 10-16) and CRP (ß = 0.31, 95%CI: 0.25-0.37, P = 10-24), and remained largely unchanged after adjustment for confounders. Longitudinally, changes in adiposity measures over approximately a decade were positively associated with changes in kynurenine metabolite concentrations (in particular for 3-hydroxyanthranilic acid, kynurenine and quinolinic acid), and more strongly so than for other markers of inflammation, including CRP. CONCLUSIONS: In middle-aged and older adults, plasma concentrations of kynurenine metabolites are strongly associated with adiposity, both cross-sectionally and longitudinally. Our study demonstrates that kynurenine metabolites may be valuable markers to monitor the adverse consequences of obesity.
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Quinurenina , Triptófano , Persona de Mediana Edad , Humanos , Anciano , Quinurenina/metabolismo , Triptófano/metabolismo , Estudios de Cohortes , Adiposidad , Ácido Quinolínico , Estudios Transversales , Inflamación , Obesidad , BiomarcadoresRESUMEN
In recent years, the incidence of depressive symptoms among Chinese college students has been increasing. Studies have shown that depressive symptoms are related to a variety of psychosocial factors, among which neuroticism, resilience, and attention bias are most notably related, but the correlation among the three is not clear. This study aimed to investigate the influence mechanisms of different degrees of resilience, attentional bias, and neuroticism in the formation of depressive symptoms. The college freshmen of this study were selected through stratified multi-stage cluster sampling. Students provided informed consent and then completed a general situation questionnaire and four scales: the Chinese version of the Connor-Davidson Resilience Scale, the Attention to Positive and Negative Information Scale, the Eysenck Personality Questionnaire, and the Zung Self-Rating Depressive Symptoms Scale. In total, 1,493 freshmen participated in the research group. Our results showed that low resilience, negative attention bias, and high neuroticism jointly increased the risk of depressive symptoms. There is a significant correlation between these three factors and depressive symptoms. Additionally, strength, tenacity, and attention bias all had more significant effects on the occurrence of depressive symptoms. These findings indicate that there may be an important psychological mechanism for the occurrence, development, and poor prognosis of depressive symptoms.
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C-type lectins (CTLs), as a member of the Ca2+-dependent carbohydrate recognition protein superfamily, play multiple roles in non-self recognition and the elimination of invading pathogens. In this study, a C-type lectin was identified and characterized from the Pacific abalone Haliotis discus hannai (designed as HdClec), and its open reading frame (ORF) encoded a polypeptide of 163 amino acids containing a typical signal peptide and only one carbohydrate-recognition domain (CRD). The deduced amino acid sequence of CRD in HdClec shared identities ranging from 22.4% to 39.8% with that of other identified CRDs of CTLs. A novel NPN motif was found in Ca2+-binding site 2 of HdClec. The mRNA transcripts of HdClec were detectable in all the examined tissues of non-stimulated abalones, with the highest expression in hepatopancreas (224.13-fold of that in gills). The expression of HdClec mRNA in hemocytes was significantly up-regulated after Vibrio harveyi challenge. Recombinant HdClec protein (rHdClec) could bind lipopolysaccharide (LPS) and peptidoglycan (PGN) in vitro in the presence of Ca2+. Coinciding with the PAMPs binding assay, rHdClec displayed broad agglutination activities towards Gram-negative bacteria V. splendidus, V. anguillarum, V. parahaemolyticus, V. harveyi, Escherichia coli, and Gram-positive bacteria Micrococcus luteus. Moreover, rHdClec could significantly elicit the chemotactic response of hemocytes in vitro. And the phagocytosis and encapsulation ability of hemocytes could be significantly enhanced by rHdClec. All these results showed that HdClec could function as pattern recognition receptors (PRRs) and further enhance the opsonization of hemocytes, which might play a crucial role in the innate immune responses of Pacific abalone.
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Hemocitos , Lectinas Tipo C , Animales , Carbohidratos , Inmunidad Innata/genética , Opsonización , Filogenia , ARN Mensajero/genética , ARN Mensajero/metabolismo , Receptores de Reconocimiento de Patrones/genética , Receptores de Reconocimiento de Patrones/metabolismoRESUMEN
In the present study, a potential probiotic Bacillus subtilis D1-2 with antibacterial activity was isolated from the gut of Apostichopus japonicus. The purpose of this experiment was to assess the effect of B. subtilis D1-2 at different concentrations (C: 0 CFU/g, BL: 105 CFU/g, BM: 107 CFU/g and BH: 109 CFU/g) on the growth performance, digestive enzyme activity, immune ability and intestinal flora of A. japonicus. After the 56-day feeding trial, the final body weight and weight gain rate of juvenile sea cucumber A. japonicus fed B. subtilis D1-2 were significantly increased, especially in the BM group. Additionally, the lipase activity of the intestine was significantly increased in the BM and BH groups. Enhanced immunity was also found in sea cucumbers supplemented with B. subtilis D1-2. Alpha diversity indices showed that the B. subtilis D1-2-supplemented groups had higher intestinal microbial richness and diversity than the control group. The beta diversity analysis indicated that the bacterial communities in the B. subtilis D1-2-supplemented groups were quite similar but different from the bacterial communities in the control group. Dietary supplementation with B. subtilis D1-2 increased the relative abundance of some potential probiotic-related genera, including Lactobacillus, Clostridium, Lactococcus, Bifidobacterium and Streptococcus. In conclusion, dietary addition of B. subtilis D1-2 could effectively promote the growth of A. japonicus, improve its digestion and immunity capacity to a certain extent, and actively regulate the intestinal microflora of A. japonicus.
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Microbioma Gastrointestinal , Probióticos , Pepinos de Mar , Stichopus , Alimentación Animal/análisis , Animales , Bacillus subtilis , Dieta/veterinaria , Digestión , Inmunidad Innata , Probióticos/análisis , Probióticos/farmacologíaRESUMEN
BACKGROUND AND AIMS: There is still inconsistent evidence over the protective effect of total bilirubin on the development of coronary heart disease (CHD). Therefore, we aimed to investigate the association between bilirubin in population subtypes and the risks of CHD between different gender and menstruation subgroups. METHODS AND RESULTS: In this prospective cohort study, 29,750 participants free of CHD with an average age of 47 ± 14 years were recruited at baseline; of these, 720 CHD first-attack cases were collected after 7-years of follow up. The covariate-adjusted Cox proportional hazards models were used to estimate hazard ratios (HRs) of CHD with 95% confidence intervals (CIs). The serum bilirubin concentration was quarterly stratified based on the distribution of healthy population without CHD onset. The HRs of incident CHD decreased with elevated bilirubin in females (ρ trend<0.05), but not males. In postmenopausal females, compared with the lowest quartile of total bilirubin, the adjusted HRs for the third and fourth quartiles were 0.64 (95% CI: 0.45, 0.93) and 0.59 (95% CI: 0.42, 0.86), the adjusted HRs in the third and fourth quartiles of direct bilirubin were 0.56 (0.39, 0.82) and 0.56 (0.38, 0.81), and for indirect bilirubin, corresponding HR in the highest quartile was 0.56 (0.38, 0.83). CONCLUSION: Elevated serum bilirubin was inversely associated with adjusted HRs of CHD in females, especially postmenopausal females. The relationship between elevated direct bilirubin and reduced HRs of CHD may be closer than indirect bilirubin in postmenopausal females.
Asunto(s)
Enfermedad Coronaria , Adulto , Bilirrubina , Enfermedad Coronaria/diagnóstico , Enfermedad Coronaria/epidemiología , Enfermedad Coronaria/prevención & control , Femenino , Humanos , Incidencia , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Factores de RiesgoRESUMEN
The photosynthetic bacterium Rhodopseudomonas palustris converts nitrogen gas (N2) to fertilizer ammonia (NH3) and also produces clean energy hydrogen gas (H2) from protons (H+) when it is grown anaerobically in nitrogen fixing medium with illumination, a condition that promotes the expression of active nitrogenase. Compared with quantitative real-time PCR (qRT-PCR) and the lacZ reporter system, two methods commonly used for in vivo study of nitrogenase regulation in photosynthetic bacteria, the fluorescent protein reporter system has advantages in terms of its simplicity and sensitivity. However, little is known concerning if the fluorescent protein reporter system can be used in bacterial cells that need to grow anaerobically. Here, we developed an RFP-based method to measure the nitrogenase gene expression in photosynthetic bacteria grown anaerobically. This method was able to determine the levels of both the genome-based and the plasmid-based nitrogenase expression under anaerobic conditions, providing a better method for in vivo study of gene expression affected by oxygen. The RFP reporter system developed here will promote a better understanding of the molecular mechanism of nitrogenase regulation and will be used on other genes of interest in a wider range of anaerobic bacteria.
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Data about the sequelae of women who infected COVID-19 while pregnant are scarce. We aimed to describe the prevalence of symptoms, pulmonary functions, and radiological changes at a follow-up of 12 months in 18 pregnant women who developed COVID-19 at different gestational ages. Our results showed that most women who infected COVID-19 while pregnant experienced a progressive improvement of their symptoms within 12 months, however, some still had little COVID-related symptoms but without a reduced quality of life. All their 18 newborns were growing up healthy.
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COVID-19 , Complicaciones Infecciosas del Embarazo , COVID-19/epidemiología , Femenino , Estudios de Seguimiento , Humanos , Recién Nacido , Transmisión Vertical de Enfermedad Infecciosa , Embarazo , Complicaciones Infecciosas del Embarazo/diagnóstico , Complicaciones Infecciosas del Embarazo/epidemiología , Mujeres Embarazadas , Calidad de Vida , SARS-CoV-2RESUMEN
BACKGROUND: We aimed to evaluate the efficacy and safety of leflunomide, an approved dihydroorotate dehydrogenase inhibitor, to treat coronavirus disease 2019 (COVID-19) patients with prolonged postsymptomatic viral shedding. METHODS: We conducted a prospective, randomized controlled, open-label trial involving hospitalized adult COVID-19 patients with prolonged polymerase chain reaction (PCR) positivity. Patients were randomly assigned to receive either leflunomide (50 mg every 12 hours, 3 consecutive times, orally; then 20 mg once daily for 8 days), in addition to nebulized interferon alpha 2a (IFN-α-2a, 3 million IU each time, twice daily for 10 days), or nebulized IFN-α-2a alone for 10 days. The primary endpoint was the duration of viral shedding. RESULTS: A total of 50 COVID-19 patients with prolonged PCR positivity were randomized into 2 groups: 26 were assigned to the leflunomide plus IFN-α-2a group, and 24 were assigned to the interferon-alone group. Treatment with leflunomide was not associated with a difference from the interferon-alone group in the duration of viral shedding (hazard ratio for negative reverse-transcription PCR, 0.70 [95% confidence interval, .391-1.256]; Pâ =â .186). In addition, the patients given leflunomide did not have a substantially shorter length of hospital stay than patients treated with interferon alone, with median durations of 29.0 (interquartile range [IQR], 19.3-47.3) days and 33.0 (IQR, 29.3-42.8) days, respectively (Pâ =â .170). Two leflunomide recipients were unable to complete the full 10-day course of administration due to adverse events. CONCLUSIONS: In COVID-19 patients with prolonged PCR positivity, no benefit in terms of the duration of viral shedding was observed with the combined treatment of leflunomide and IFN-α-2a beyond IFN-α-2a alone.
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COVID-19 , Adulto , Antivirales/farmacología , Antivirales/uso terapéutico , Dihidroorotato Deshidrogenasa , Humanos , Leflunamida/farmacología , Estudios Prospectivos , SARS-CoV-2 , Resultado del Tratamiento , Esparcimiento de VirusRESUMEN
The coronavirus disease 2019 (COVID-19) has caused a global pandemic, resulting in considerable morbidity and mortality. Tocilizumab, an inhibitor of IL-6, has been widely repurposed as a treatment of severely ill patients without robust evidence supporting its use. In this study, we aimed to systematically describe the effectiveness of treatment and prevention of the cytokine storms in COVID-19 patients with tocilizumab. In this multicentered retrospective and observational cohort study, 65 patients with COVID-19 receiving tocilizumab and 130 not receiving tocilizumab were propensity score matched at a ratio of 2:1 based on age, sex, and comorbidities from January 20, 2020 to March 18, 2020 in Wuhan, China. After adjusting for confounding, the detected risk for in-hospital death was lower in the tocilizumab group versus nontocilizumab group (hazard ratio = 0.47; 95% confidence interval = 0.25-0.90; p = 0.023). Moreover, use of tocilizumab was associated with a lower risk of acute respiratory distress syndrome (odds ratio = 0.23; 95% confidence interval = 0.11-0.45; p < 0.0001). Furthermore, patients had heightened inflammation and more dysregulated immune cells before treatment, which might aggravate disease progression. After tocilizumab administration, abnormally elevated IL-6, C-reactive protein, fibrinogen, and activated partial thromboplastin time decreased. Tocilizumab may be of value in prolonging survival in patients with severe COVID-19, which provided a novel strategy for COVID-19-induced cytokine release syndrome. Our findings could inform bedside decisions until data from randomized, controlled clinical trials become available.
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Anticuerpos Monoclonales Humanizados/uso terapéutico , Tratamiento Farmacológico de COVID-19 , COVID-19/complicaciones , Síndrome de Liberación de Citoquinas/complicaciones , Síndrome de Liberación de Citoquinas/tratamiento farmacológico , Reposicionamiento de Medicamentos , Síndrome de Dificultad Respiratoria/complicaciones , Síndrome de Dificultad Respiratoria/tratamiento farmacológico , Anciano , COVID-19/inmunología , Estudios de Cohortes , Síndrome de Liberación de Citoquinas/inmunología , Femenino , Humanos , Interleucina-6/inmunología , Masculino , Persona de Mediana Edad , Síndrome de Dificultad Respiratoria/inmunología , Estudios Retrospectivos , SARS-CoV-2 , Índice de Severidad de la EnfermedadRESUMEN
Purpose: In this study, we investigated the acute exacerbation and outcomes of COPD patients during the outbreak of COVID-19 and evaluated the prevalence and mortality of COPD patients with confirmed COVID-19. Methods: A prospectively recruited cohort of 489 COPD patients was retrospectively followed-up for their conditions during the COVID-19 pandemic from December 2019 to March 2020 in Hubei, China. In addition, the features of 821 discharged patients with confirmed COVID-19 were retrospectively analyzed. Results: Of the 489 followed-up enrolled COPD patients, 2 cases were diagnosed as confirmed COVID-19, and 97 cases had exacerbations, 32 cases of which were hospitalized, and 14 cases died. Compared with the 6-month follow-up results collected 1 year ago, in 307 cases of this cohort, the rates of exacerbations and hospitalization of the 489 COPD patients during the last 4 months decreased, while the mortality rate increased significantly (2.86% vs 0.65%, p=0.023). Of the 821 patients with COVID-19, 37 cases (4.5%) had pre-existing COPD. Of 180 confirmed deaths, 19 cases (10.6%) were combined with COPD. Compared to COVID-19 deaths without COPD, COVID-19 deaths with COPD had higher rates of coronary artery disease and/or cerebrovascular diseases. Old age, low BMI and low parameters of lung function were risk factors of all-cause mortality for COVID-19 patients with pre-existing COPD. Conclusion: Our findings imply that acute exacerbations and hospitalizations of COPD patients were infrequent during the COVID-19 pandemic. However, COVID-19 patients with pre-existing COPD had a higher risk of all-cause mortality.
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Infecciones por Coronavirus , Hospitalización/estadística & datos numéricos , Pandemias , Neumonía Viral , Enfermedad Pulmonar Obstructiva Crónica , Brote de los Síntomas , COVID-19 , Prueba de COVID-19 , China/epidemiología , Técnicas de Laboratorio Clínico/métodos , Comorbilidad , Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/mortalidad , Infecciones por Coronavirus/terapia , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mortalidad , Evaluación de Procesos y Resultados en Atención de Salud , Neumonía Viral/epidemiología , Neumonía Viral/mortalidad , Neumonía Viral/terapia , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Enfermedad Pulmonar Obstructiva Crónica/terapia , Factores de RiesgoRESUMEN
OBJECTIVES: To investigate the proportion and characteristics of asymptomatic infection among healthcare workers (HCWs). METHODS: This study retrospectively investigated 1407 HCWs who were screened for COVID-19 by chest computed tomography (CT) scans and nasopharyngeal swabs for SARS-CoV-2 nucleic acid. Demographics, CT features, nasopharyngeal swabs, baseline symptoms, and laboratory data were collected. RESULTS: Of 1407 HCWs, 235 had symptoms and 1172 were asymptomatic close contacts, of which, 107 were symptomatic cases and 84 were close contacts who had abnormal CT findings. Of 152 symptomatic individuals and 908 close contacts tested for SARS-CoV-2 nucleic acid, 122 symptomatic cases and 38 close contacts had positive reverse-transcriptase real-time polymerase chain (RT-PCR) test results. The rate of confirmed asymptomatic infections was 4.2% (38/908). Both symptomatic and asymptomatic infected cases had high titrations of specific IgG or had ≥four-fold increase in IgG during convalescence compared with the acute phase. Combining the RT-PCR tests and serological findings, the rate of asymptomatic infections was 9.7% (88/908). In terms of the duration of viral shedding, there was no significant difference between symptomatic mild/moderate participants and asymptomatic infections. CONCLUSIONS: The findings demonstrated that a high rate of asymptomatic SARS-CoV-2 carriers existed among healthcare worker close contacts during the outbreak of COVID-19.
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Infecciones Asintomáticas/epidemiología , Betacoronavirus , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/patología , Personal de Salud , Hospitales de Enseñanza , Neumonía Viral/epidemiología , Neumonía Viral/patología , Adulto , COVID-19 , Portador Sano , China/epidemiología , Infecciones por Coronavirus/diagnóstico , Femenino , Humanos , Masculino , Pandemias , Neumonía Viral/diagnóstico , Estudios Retrospectivos , SARS-CoV-2 , Esparcimiento de Virus , Adulto JovenRESUMEN
BACKGROUND: The number of coronavirus disease 2019 (COVID-19) cases has rapidly increased all over the world. Specific information about immunity in non-survivors with COVID-19 is scarce. This study aimed to analyse the clinical characteristics and abnormal immunity of the confirmed COVID-19 non-survivors. METHODS: In this single-centered, retrospective, observational study, we enrolled 125 patients with COVID-19 who were died between January 13 and March 4, 2020 in Renmin Hospital of Wuhan University. A total of 414 randomly recruited patients with confirmed COVID-19 who were discharged from the same hospital during the same period served as control. The demographic, clinical characteristics and laboratory findings at admission, and treatment used in these patients were collected. The immunity-related risk factors associated with in-hospital death were tested by logistic regression models and Receiver Operating Characteristic (ROC) curve. RESULTS: Non-survivors (70 years, IQR: 61.5-80) were significantly older than survivors (54 years, IQR: 37-65) (P < 0.001). 56.8% of non-survivors was male. Nearly half of the patients (44.9%) had chronic medical illness. In non-survivors, hypertension (49.6%) was the most common comorbidity, followed by diabetes (20.0%) and coronary heart disease (16.0%). The common signs and symptoms at admission of non-survivors were fever (88%), followed by cough (64.8%), dyspnea (62.4%), fatigue (62.4%) and chest tightness (58.4%). Compared with survivors, non-survivors had higher white blood cell (WBC) count (7.85 vs 5.07 × 109/L), more elevated neutrophil count (6.41 vs 3.08 × 109/L), smaller lymphocyte count (0.69 vs 1.20 × 109/L) and lower platelet count (172 vs 211 × 109/L), raised concentrations of procalcitonin (0.21 vs 0.06 ng/mL) and CRP (70.5 vs 7.2 mg/L) (P < 0.001). This was accompanied with significantly decreased levels of CD3+ T cells (277 vs 814 cells/µl), CD4+ T cells (172 vs 473 cells/µl), CD8+ T cells (84 vs 262.5 cells/µl, P < 0.001), CD19+ T cells (88 vs 141 cells/µl) and CD16+ 56+ T cells (79 vs 128.5 cells/µl) (P < 0.001). The concentrations of immunoglobulins (Ig) G (13.30 vs 11.95 g/L), IgA (2.54 vs 2.21 g/L), and IgE (71.30 vs 42.25 IU/ml) were increased, whereas the levels of complement proteins (C)3 (0.89 vs 0.99 g/L) and C4 (0.22 vs 0.24 g/L) were decreased in non-survivors when compared with survivors (all P < 0.05). The non-survivors presented lower levels of oximetry saturation (90 vs 97%) at rest and lactate (2.40 vs 1.90 mmol/L) (P < 0.001). Old age, comorbidity of malignant tumor, neutrophilia, lymphocytopenia, low CD4+ T cells, decreased C3, and low oximetry saturation were the risk factors of death in patients with confirmed COVID-19. The frequency of CD4+ T cells positively correlated with the numbers of lymphocytes (r = 0.787) and the level of oximetry saturation (r = 0.295), Whereas CD4+ T cells were negatively correlated with age (r =-0.323) and the numbers of neutrophils (r = - 0.244) (all P < 0.001). CONCLUSIONS: Abnormal cellular immunity and humoral immunity were key features of non-survivors with COVID-19. Neutrophilia, lymphocytopenia, low CD4+ T cells, and decreased C3 were immunity-related risk factors predicting mortality of patients with COVID-19.
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Infecciones por Coronavirus/inmunología , Infecciones por Coronavirus/mortalidad , Neumonía Viral/inmunología , Neumonía Viral/mortalidad , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Betacoronavirus/aislamiento & purificación , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , COVID-19 , China/epidemiología , Infecciones por Coronavirus/sangre , Infecciones por Coronavirus/epidemiología , Femenino , Humanos , Recuento de Leucocitos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Neutrófilos/inmunología , Pandemias , Neumonía Viral/sangre , Neumonía Viral/epidemiología , Curva ROC , Estudios Retrospectivos , Factores de Riesgo , SARS-CoV-2 , Adulto JovenRESUMEN
We recently reported that inhibitors against human dihydroorotate dehydrogenase (DHODH) have broad-spectrum antiviral activities including their inhibitory efficacies on SARS-CoV-2 replication in infected cells. However, there are limited data from clinical studies to prove the application of DHODH inhibitors in Coronavirus disease 2019 (COVID-19) patients. In the present study, we evaluated Leflunomide, an approved DHODH inhibitor widely used as a modest immune regulator to treat autoimmune diseases, in treating COVID-19 disease with a small-scale of patients. Cases of 10 laboratory-confirmed COVID-19 patients of moderate type with obvious opacity in the lung were included. Five of the patients were treated with Leflunomide, and another five were treated as blank controls without a placebo. All the patients accepted standard supportive treatment for COVID-19. The patients given Leflunomide had a shorter viral shedding time (median of 5 days) than the controls (median of 11 days, P = 0.046). The patients given Leflunomide also showed a significant reduction in C-reactive protein levels, indicating that immunopathological inflammation was well controlled. No obvious adverse effects were observed in Leflunomide-treated patients, and they all discharged from the hospital faster than controls. This preliminary study on a small-scale compassionate use of Leflunomide provides clues for further understanding of Leflunomide as a potential antiviral drug against COVID-19.
Asunto(s)
Antivirales/administración & dosificación , Tratamiento Farmacológico de COVID-19 , Leflunamida/administración & dosificación , Anciano , Proteína C-Reactiva/metabolismo , COVID-19/diagnóstico por imagen , COVID-19/metabolismo , COVID-19/virología , China , Femenino , Humanos , Pulmón/diagnóstico por imagen , Pulmón/efectos de los fármacos , Masculino , Persona de Mediana Edad , SARS-CoV-2/efectos de los fármacos , SARS-CoV-2/fisiología , Replicación Viral/efectos de los fármacos , Esparcimiento de Virus/efectos de los fármacosRESUMEN
BACKGROUND AND AIM: Both chronic intermittent hypoxia (CIH) and chronic continuous hypoxia (CCH) are risk factors for cardiovascular disease, which are associated with cardiac systolic function and associated with dysfunction of endothelia and coagulation-fibrinolysis system in the vasculature. However, the different effects of these two hypoxic models are not fully understood. In our study, we systemically compared the effects of CIH and CCH on cardiac function and related factor levels in serum using rat model. METHODS: Forty-five male Sprague-Dawley rats were randomly divided into the normoxia control (NC), CIH and CCH groups. The rat CIH and CCH models were established, then the blood and tissue samples were collected to analyze the function of endothelium and the coagulation-fibrinolysis system. Also, the ultrasound cardiogram was performed to directly assess myocardial contractility. RESULTS: Both CIH and CCH significantly decreased the NO, eNOS, P-eNOS and AT-III levels in the rat serum but significantly increased the levels of ET-1, vWF, COX-2, NF-κB, FIB, FVIII and PAI-1 in the rat serum (Pâ<â0.05). The expression of ET-1, VWF and ICAM-1 in CIH group were higher than CCH group (Pâ<â0.05), however, the expression of CD62p was increased in CCH group but not in CIH group. The expression of t-PA in CIH group were lower than CCH group (Pâ<â0.05), but there were no significant differences in CCH group and NC group (Pâ>â0.05). Using transmission electron microscope, we found that the mitochondrial ultrastructure of thoracic aorta endothelial cells in CIH and CCH group were damaged. Moreover, the myocardial contractility in CIH and CCH group were significantly decreased compared with NC group. CONCLUSION: Our results suggested that CIH and CCH could cause endothelial dysfunction, dysfunction of the coagulation-fibrinolysis system and decreasing of myocardial contractility. Compared with CCH, CIH has greater effect on vasoconstriction and adhesion of vascular endothelial cells, and stronger procoagulant effect.
Asunto(s)
Hipoxia de la Célula/genética , Endotelio/metabolismo , Animales , Enfermedad Crónica , Células Endoteliales/metabolismo , Masculino , Ratas , Ratas Sprague-DawleyRESUMEN
BACKGROUND: The nocturnal intermittent hypoxia caused by obstructive sleep apnea syndrome (OSAS) can provoke the sympathetic nervous activity (SNA). Salivary alpha-amylase (sAA) is a sensitive, non-invasive biomarker for reflecting the SNA, and a useful marker for pediatric OSAS subjects. Adenotonsillar hypertrophy (ATH) is the most commonly identified risk factor in OSAS childhood, therefore, several studies showed that the adenotonsillectomy (T&A) may alleviate nocturnal enuresis (NE) in children with OSAS. OBJECTIVE: The present study was to investigate the effect of T&A on NE, the change of sAA value in ATH and OSAS children, with/without NE, and with/without the operation. STUDY DESIGN: 37 children (Group A) were admitted for ATH and NE. The saliva samples were taken before and after polysomnography for the measure of sAA. After the T&A, the children were followed-up for 1 year. 35 OSAS children with NE but no T&A were as a NE watchful-waiting group (Group B), 32 subjects without OSAS or NE were as non-OSAS control (Group C), 42 cases who underwent T&A but did not have NE were admitted to evaluate the SNA (Group D). Follow-up included evaluations for NE, sAA and urinary catecholamine after the T&A or at the equivalent time points. RESULTS: The observational results in the present study showed a significant rate of the disappearance of NE 1 month after the T&A and had an almost complete resolution 1 year later. OSAS may irritate oxidative stress and increase SNA in pediatric subjects, which reflected by increased levels of sAA and urinary catecholamine, while the T&A can decrease enuresis and the SNA in children with OSAS (Figure). DISCUSSION: Little research has previously focused on the relationship between childhood OSAS and the SNA. No data are currently available regarding comparisons of sAA levels before and after the T&A in children with OSAS and enuresis. Our findings in this present study showed that there was a resolution or decrease in enuresis events and drops in sAA levels following T&A, which were consistent with earlier study. However, there was no significant difference in the urinary catecholamine levels was found between OSAS groups with or without NE. Furthermore, there was no correlation between the urinary catecholamine and polysomnography parameters. CONCLUSIONS: T&A has a favorable therapeutic effect on NE and may decrease SNA in children with OSAS. sAA might be associated with instability of ANS by OSAS and have a consistent relationship with the apnea-hypopnea index. Our studying aims had been met.