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1.
J Med Virol ; 2020 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-32383171

RESUMEN

On March 31, 2020, Chinese Health Authorization announced that numbers of asymptomatic cases with SARS-CoV-2 infection will be made to public daily. This was a very important step since different counties have different capacity for detection of SARS-CoV-2 infection and control strategy for COVID-19 outbreak. We summarized the characteristics of asymptomatic SARS-CoV-2 infections and the transmission potential of asymptomatic cases. Then we provided guidelines fo_r the management of asymptomatic cases through quarantine and nucleic acid/serology tests. This article is protected by copyright. All rights reserved.

2.
ACS Appl Mater Interfaces ; 12(16): 18332-18341, 2020 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-32239905

RESUMEN

Shiga toxin-producing Escherichia coli (STEC) are critical foodborne pathogens, which cause serious human health issues, including hemolytic uremic syndrome. Illnesses caused by STEC lack effective treatments that target the elimination of these bacteria from the gastrointestinal tract without causing an adverse effect. Reducing this pathogen from a reservoir of STEC is an effective strategy, but the challenges remain due to the lack of efficient, selective antimicrobial agents. We developed specific antibody-conjugated chitosan nanoparticles (CNs) to selectively target and treat STEC in the gastrointestinal tract. Given the great broad-spectrum antimicrobial activity of CN, we conjugated antibodies to CN. Antibodies were raised and purified from egg yolks after immunization of hens with seven different O-side-chain antigens isolated from STEC (O26, O45, O103, O111, O121, O145, and O157). We prepared CN-immunoglobulin Y (IgY) conjugates by forming amide bonds at different ratios of CN:IgY (10:1, 10:2, and 10:4). The CN-IgY conjugated at a 10:2 ratio demonstrated significantly enhanced antimicrobial activity against E. coli O157:H7. Conjugates of CN and anti-STEC IgY antibodies killed corresponding STEC serotypes specifically and selectively, while showing no significant impact on nontargeted bacteria, including Salmonella enterica and Lactobacillus plantarum. The enhanced antimicrobial activity of CN-IgY against STEC was also confirmed in synthetic intestinal fluid, as well as an in vivo animal model of Caenorhabditis elegans. These results suggest that the CN-IgY conjugates have strong and specific antimicrobial activity and that they are also great candidates to eliminate pathogens selectively in the gastrointestinal tract without inhibiting beneficial bacteria.

3.
Chest ; 2020 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-32224074

RESUMEN

BACKGROUND: Since the outbreak of coronavirus disease 2019 (COVID-19) in China in December 2019, considerable attention has been focused on its elucidation. However, it is also important for clinicians and epidemiologists to differentiate COVID-19 from other respiratory infectious diseases such as influenza viruses. RESEARCH QUESTION: The aim of this study was to explore the different clinical presentations between COVID-19 and influenza A (H1N1) pneumonia in patients with ARDS. STUDY DESIGN AND METHODS: This analysis was a retrospective case-control study. Two independent cohorts of patients with ARDS infected with either COVID-19 (n = 73) or H1N1 (n = 75) were compared. Their clinical manifestations, imaging characteristics, treatments, and prognosis were analyzed and compared. RESULTS: The median age of patients with COVID-19 was higher than that of patients with H1N1, and there was a higher proportion of male subjects among the COVID-19 cohort (P < .05). Patients with COVID-19 exhibited higher proportions of nonproductive coughs, fatigue, and GI symptoms than those of patients with H1N1 (P < .05). Patients with H1N1 had higher Sequential Organ Failure Assessment (SOFA) scores than patients with COVID-19 (P < .05). The Pao2/Fio2 of 198.2 mm Hg in the COVID-19 cohort was significantly higher than the Pao2/Fio2 of 107.0 mm Hg in the H1N1 cohort (P < .001). Ground-glass opacities was more common in patients with COVID-19 than in patients with H1N1 (P < .001). There was a greater variety of antiviral therapies administered to COVID-19 patients than to H1N1 patients. The in-hospital mortality of patients with COVID-19 was 28.8%, whereas that of patients with H1N1 was 34.7% (P = .483). SOFA score-adjusted mortality of H1N1 patients was significantly higher than that of COVID-19 patients, with a rate ratio of 2.009 (95% CI, 1.563-2.583; P < .001). INTERPRETATION: There were many differences in clinical presentations between patients with ARDS infected with either COVID-19 or H1N1. Compared with H1N1 patients, patients with COVID-19-induced ARDS had lower severity of illness scores at presentation and lower SOFA score-adjusted mortality.

5.
Cell Immunol ; 352: 104098, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32241531

RESUMEN

Asthma is an inflammatory disease of the airways and numerous cytokines contribute to this pathogenesis. It is shown that challenge of airways with IL-33 induces asthma-like pathological changes in mice, but the possible downstream cytokines in this process remain to be characterised. To explore this, we compared changes in the airways of wildtype (WT) and IL-9 deficient mice challenged with IL-33. In line with previous report, per-nasal challenge of WT mice with IL-33 significantly increased the responsiveness of the airways along with infiltration of inflammatory cells, goblet cell hyperplasia, collagen deposition and smooth muscle hypertrophy, and the expression of cytokines compared with control group. Surprisingly, all of these pathological changes were significantly attenuated in IL-9 deficient mice following identical IL-33 challenge. These data suggest that IL-9 is one downstream cytokine relevant to the effects of IL-33 in asthmatic airways and consequently a potential therapeutic target for the treatment of asthma.

6.
Can Respir J ; 2020: 2301712, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32211084

RESUMEN

Severe bronchial asthma complicated with respiratory failure, a common critical illness in respiratory medicine, may be life-threatening. High-flow nasal cannula (HFNC) is a novel oxygen therapy technique developed in recent years. HFNC was applied in this study for treating adult patients with severe bronchial asthma complicated with respiratory failure. Its efficacy was analyzed comparatively to conventional oxygen therapy (COT). HFNC and COT were randomly performed based on conventional treatment. The HFNC group was similar to COT-treated patients in terms of response rate, with no significant difference in efficacy between the two groups. In patients with bronchial asthma, effectively increased PO2 and reduced PCO2 were observed after treatment in both groups. However, HFNC was more efficient than COT in elevating PO2 in patients with severe bronchial asthma complicated with respiratory failure, while no statistically significant difference in PCO2 reduction was found between the two groups. Heart rate (HR) and respiratory rate (RR) between the two groups on admission (0 h) and at 2, 8, 24, and 48 h after admission were compared. Both indicators significantly decreased with time. No significant differences in HR and RR were found between the groups at 0, 2, and 8 h after admission. However, these indicators were significantly lower in the HFNC group compared with the COT group at 24 and 48 h after admission. HFNC could significantly elevate PO2 and reduce HR and RR. Thus, it is a promising option for patients with severe bronchial asthma complicated with respiratory failure.

8.
Artículo en Inglés | MEDLINE | ID: mdl-32048861

RESUMEN

Pneumocystis is an unusual, opportunistic fungal pathogen capable of causing Pneumocystis pneumonia (PCP) in immunocompromised hosts. Though PCP was discovered more than 100 years ago, its pathogenesis remains unclear. The inhibitory receptor programmed death 1 (PD-1), a negative regulator of activated T cells, has been reported to take part in tumor escape, immune tolerance, and infection immunity. In this study, we examined the role of the PD-1/programmed death-ligand 1 (PD-L1) pathway in PCP patients and mice. The expression levels of PD-1/PD-L1 in PCP patients and mice were measured by real-time PCR and flow cytometry. The effects of PD-1 deficiency are demonstrated using wild-type and PD-1-/- mice. Our data show that Pneumocystis infection promotes PD-1/PD-L1 expression; PD-1 deficiency enhances the phagocytic function of macrophages and the pulmonary Th1/Th17 response, which might contribute to Pneumocystis clearance; PD-1 deficiency affects the polarization of macrophages. PCP mice treated with anti-PD-1 antibody showed improved pulmonary clearance of Pneumocystis. Collectively, our results demonstrate that the PD-1/PD-L1 pathway plays a role in regulating the innate and adaptive immune responses, suggesting that manipulation of this pathway may constitute an immunotherapeutic strategy for PCP.

10.
BMC Infect Dis ; 20(1): 155, 2020 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-32075600

RESUMEN

BACKGROUND: Sepsis is a life-threatening situation, and it can be rendered more severe by coagulopathy. We here examine a novel plasma biomarker for sepsis-induced coagulopathy. METHODS: A total of 116 patients diagnosed with sepsis were recruited and divided into two groups by whether they also had coagulopathy. Plasma samples were collected on arrival at the intensive care unit. Fifteen sepsis-alone and 15 sepsis-induced coagulopathy plasma samples were mixed and sent for microRNA sequencing. Differently expressed microRNAs were then validated by quantitative reverse transcriptase polymerase chain reaction in 52 sepsis-alone and 34 sepsis-induced coagulopathy patients; plasma lipocalin-2 was measured as well. RESULTS: Four microRNAs were selected from microRNA sequencing. Only hsa-mir-92a-3p was differently expressed in the validation set. Its level of expression was significantly lower in sepsis-induced coagulopathy group. Hsa-mir-92a-3p had an area under a receiver operating characteristic curve of 0.660 (95% confidence interval, 0.537, 0.782). The plasma Hsa-mir-92a-3p level was related to activated partial thromboplastin time, prothrombin activity, and plasma lipocalin-2 level. A binary logistic model showed an association between hsa-mir-92a-3p and fibrinogen with SIC. CONCLUSIONS: The utility of hsa-mir-92a-3p as a biomarker for sepsis-induced coagulopathy needs more verification, and the regulatory mechanism of hsa-mir-92a-3p in coagulation disorder and its potency as a therapeutic target must be confirmed.


Asunto(s)
Biomarcadores/sangre , Trastornos de la Coagulación Sanguínea/etiología , Lipocalina 2/sangre , MicroARNs/sangre , Sepsis/complicaciones , Adulto , Anciano , Femenino , Regulación de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Curva ROC , Sepsis/sangre , Sepsis/diagnóstico
11.
Chin Med J (Engl) ; 133(9): 1121-1122, 2020 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-32068600
13.
Postgrad Med ; : 1-6, 2020 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-32077354

RESUMEN

Background: Patients with undiagnostic pleural effusions are routinely examined by conventional medical thoracoscopy under the white light (WL). The endoscopic appearance of pleural diseases under WL could be misleading. Narrow-Band Imaging (NBI) has been applied as an interesting and effective diagnostic tool for endoscopy. However, there is also controversy about its value in the application of thoracoscopy.Objective: The objective of this study was to investigate the diagnostic value of NBI technology during thoracoscopy.Methods: Patients with undiagnosed pleural effusions admitted to our hospital between September 2017 and September 2019 were enrolled. During the thoracoscopy, we performed WL mode first and then NBI. Pictures of endoscopic real-time lesions were recorded under two modes, and at least five pieces of tissue were taken, respectively, on pleura lesions. Biopsy specimens were respectively taken for pathologic analysis. Diagnostic sensitivity, specificity were calculated to compare with pathologic results.Results: 100 eligible patients were enrolled, including 63 with malignancy, 23 with tuberculous pleurisy, 3 with systemic disease and 11 with the negative condition. Compared with pathological results, the sensitivity of WL was 91.01%, and NBI 84.27%; while the specificity of WL was 27.27%, and NBI 81.82%. Compared NBI with WL, the former's specificity is superior to the latter's, which is statistically significant (P < 0.05).Conclusions: The advantage of NBI lies in its high specificity. It's useful to diagnose unknown pleural effusions in clinical practice. With better visualization of blood vessels, we can enhance the accuracy of biopsy and reduce the risk of unexpected bleeding arose from the biopsy.

14.
Eur J Clin Microbiol Infect Dis ; 39(2): 369-374, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31813078

RESUMEN

The purpose of this study was to assess the value of metagenomic next-generation sequencing (mNGS) of bronchoalveolar lavage fluid (BALF) for the diagnosis of severe respiratory diseases based on interpretation of sequencing results. BALF samples were harvested and used for mNGS as well as microbiological detection. Infectious bacteria or fungi were defined according to relative abundance and number of unique reads. We performed mNGS on 35 BALF samples from 32 patients. The positive rate reached 100% in the mNGS analysis of nine immunocompromised patients. Compared with the culture method, mNGS had a diagnostic sensitivity of 88.89% and a specificity of 74.07% with an agreement rate of 77.78% between these two methods. Compared with the smear method and PCR, mNGS had a diagnostic sensitivity of 77.78% and a specificity of 70.00%. In 13 cases, detection results were positive by mNGS but negative by culture/smear and PCR. The mNGS findings in 11/32 (34.4%) cases led to changes in treatment strategies. Linear regression analysis showed that diversity was significantly correlated with interval between disease onset and sampling. Dynamic changes in reads could indirectly reflect therapeutic effectiveness. BALF mNGS improves sensitivity of pathogen detection and provides guidance in clinical practice. Potential pathogens can be identified based on relative abundance and number of unique reads.

15.
Environ Pollut ; 256: 113410, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31679873

RESUMEN

Amaranth (Amaranthus mangostanus L.) has superior capability for accumulating cadmium (Cd) and has the potential to be used for phytoremediation of Cd contaminated soils. Iron (Fe) is chemically similar to Cd and may mediate Cd-induced physiological or metabolic impacts in plants. The purpose was to investigate the model of time-dependent and concentration-dependent kinetics of Cd absorption under Fe deficiency, understanding the physiological mechanism of Cd absorption in amaranth roots. The kinetic characteristics of Cd uptake by amaranth grown in Cd enriched nutritional solution with or without Fe addition and with methanol-chloroform, carbonyl cyanide 3-chlorophenylhydrazone (CCCP), and lanthanum chloride (LaCl3) were compared using 109Cd2+ isotope labeling technique. The results showed that Cd uptake was time-dependent and about 90-93% of uptake occurred during the first 150 min. The kinetics of Cd uptake showed that two stages were involved. The saturation stage fitted the Michaelis-Menten model when concentrations of Cd were lower than 12.71 µmol/L and then the absorption of Cd by roots was increased linearly during the second stage. Only linear absorption was observed with methanol-chloroform treatment while the metabolic inhibitor CCCP inhibited only the saturation absorption process, and the Ca channel inhibitor LaCl3 partially inhibited the two stages of absorption. These results indicated that the root absorption of 109Cd2+ was enhanced under Fe deficiency which induced more Fe transporters in the root cell membrane, and the Ca channel, apoplastic and symplastic pathways enhanced the Cd absorption in roots.


Asunto(s)
Amaranthus/metabolismo , Cadmio/metabolismo , Contaminantes del Suelo/metabolismo , Anemia Ferropénica , Biodegradación Ambiental , Transporte Biológico , Cadmio/análisis , Hierro/metabolismo , Raíces de Plantas/metabolismo
16.
Respir Care ; 65(3): 369-376, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31744865

RESUMEN

BACKGROUND: Various studies have been performed to examine the effect of high-flow nasal cannula (HFNC) in immunocompromised patients with acute respiratory failure (ARF). However, the results were inconsistent. Thus, we conducted a meta-analysis to evaluate the effect of HFNC oxygen therapy in immunocompromised patients with ARF versus conventional oxygen therapy and noninvasive ventilation (NIV). METHODS: Relevant studies published prior to May 11, 2019, were systematically searched. The primary outcome was intubation rate; secondary outcomes were mortality (ICU mortality, in-hospital mortality, and 90-d mortality) and ICU-acquired infections. Data were pooled using the random effects model. RESULTS: Of 832 identified studies, 8 were eligible for inclusion in our analysis (N = 2,167 subjects). HFNC was associated with lower intubation rates compared to conventional oxygen therapy (risk ratio [RR] 0.89, 95% CI 0.79-1.00, P = .040), but we found no significant difference in the rate between HFNC and NIV (RR 0.74, 95% CI 0.46-1.19, P = .22). We also found that HFNC did not increase the risk of ICU-acquired infections (RR 0.86, 95% CI 0.63-1.18, P = .35). However, in comparison to other noninvasive therapies, HFNC exhibited no differences in ICU mortality (RR 0.82, 95% CI 0.58-1.17, P = .28), in-hospital mortality (RR 0.92, 95% CI 0.74-1.15, P = .48), or 90-d mortality (RR 0.98, 95% CI 0.81-1.18, P = .82). CONCLUSIONS: Our results suggest that HFNC may be a feasible alternative to NIV, with lower intubation rates and no increased risk for ICU-acquired infections compared to standard oxygen therapy. However, HFNC did not appear to reduce mortality in immunocompromised subjects with ARF compared with other noninvasive therapies. Further high-quality randomized controlled trials should be performed to confirm these findings.

17.
Environ Sci Pollut Res Int ; 27(7): 7420-7429, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31884531

RESUMEN

Biochar, a low-cost porous carbonaceous adsorbent, has low adsorption capacity for anion contaminants. The objective of this study was to improve biochar's ability to adsorb phosphorus (P) through polyethyleneimine (PEI) modification to form an amine-functionalized biochar. Biochars prepared by pyrolysis of bamboo biomass, before and after PEI modification, were characterized using the Fourier transformed infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), elemental analysis, and batch sorption experiments. The effects of pH, coexisting anions, and ionic strength on P adsorption by PEI-modified biochar were also investigated. Results indicated that PEI was successfully grafted onto biochar which resulted an increase in surface amine group and in P adsorption. The peak of P adsorption occurred at pH of three and adsorption of P was decreased with increasing of ionic strength and when coexisting ions, such as HCO3-, SO42-, NO3-, and Cl-, were coexisted. The electrostatic interaction between P and surface functional groups of PEI-modified biochar served as the primary mechanism controlling the adsorption process. These results indicate that chemically functionalized biochar with amine groups can enhance P adsorption.

18.
Tob Induc Dis ; 17: 73, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31768165

RESUMEN

INTRODUCTION: Healthcare information systems (HIS) are used to aid healthcare providers delivering brief smoking cessation interventions. However, evidence regarding the effectiveness of intervention models in developing countries remains limited. A smoking cessation intervention model based on a decision support tool embedded in HIS (an 'e-information model', including Ask, Advise, Assess, Inform, Refer and Print components) was applied in a large urban general hospital in Beijing, China. The current study was a preliminary evaluation of the implementation and effectiveness of this model. METHODS: We conducted a retrospective investigation in the outpatient department of the hospital in the period June-July 2017. Using a paper questionnaire, patients' self-reported receipt of the e-information model in the past 2 months and their plans to quit within 1 month were collected. Multivariate logistic regression analysis was used to examine the association between receiving the e-information model and patients' plans to quit. RESULTS: Among 656 currently smoking patients, the proportion of patients receiving the Ask, Advise, Assess, Refer and Print components were 73.2%, 65.4%, 49.8%, 16.0% and 10.4%, respectively. The results revealed a dose-response relationship between the number of components received and the proportion of patients planning to quit (p-trend=0.006). The likelihood of patients planning to quit within 1 month was highest among those receiving all five components (OR=2.79, 95% CI: 1.31-5.94). Moreover, a simplified model composed of two or three components also revealed a potential effect on increasing the proportion of patients planning to quit. CONCLUSIONS: The e-information model was applied effectively in the study hospital and appeared to encourage patients to plan to quit smoking. This model could be generalized to other hospitals in China and other developing countries. However, many components of this model were less utilized, and comprehensive measures will be required to improve its application in the future.

19.
Mediators Inflamm ; 2019: 6750861, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31582901

RESUMEN

Background: Pneumocystis pneumonia (PCP) remains a common opportunistic infection in immunosuppressed individuals. Current studies showed that multiple immune cells and cytokines took part in the host defense against Pneumocystis (PC). However, the roles of IL-17 and IL-10 in the development of PCP have not been elucidated. Methods: IL-10 and IL-17 levels in serum from PCP mice were detected via ELISA. The percentages of B10 cells, IL-10+ macrophages, and IL-10+ T cells in the lung from IL-17-/- PCP mice and Th17 cells and IL-17+ γδT cells in IL-10-/- PCP mice were examined via flow cytometry. Also, antibody neutralization examination was also performed to elucidate the relationship of IL-17 and IL-10 in the PCP model. Results: We noted the increase of IL-17 and IL-10 levels in serum from mice infected with Pneumocystis. Furthermore, deficiency of IL-17 or IL-10 could lead to the delayed clearance of Pneumocystis and more severed lung damage. Our data also demonstrated that IL-17 deficiency enhanced the serum IL-10 level and the percentages of B10 cells, IL-10+ macrophages, and IL-10+ T cells in the lung from PCP mice. Interestingly, we also noted an increase of the IL-17 level in serum and Th17 cell and IL-17+ γδT cell percentages in the lung from IL-10-/- PCP mice. Using antibody neutralization experiments, we found that the STAT3 gene might play a critical role in the interplay of IL-17 and IL-10 in PCP. Conclusion: Taken together, our results demonstrated that IL-17 and IL-10 could play the protective roles in the progression of PCP and the inverse correlation of them might be mediated by STAT3.

20.
Carbohydr Polym ; 225: 115207, 2019 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-31521293

RESUMEN

Cellulose-based biocompatible, tunable and injectable hydrogels embedded with pH-responsive diblock copolymer micelles were constructed to achieve localized drug delivery with prolonged, stimuli-driven and slow-release function. First, we prepared two types of modified carboxymethyl cellulose (CMC) including hydrazide-modified carboxymethyl cellulose (CMC-NH2) and oxidized carboxymethyl cellulose (CMC-CHO) with varying degrees of oxidation. Then, pH-responsive poly (ethylene oxide)-block-poly (2-(diisopropylamino) ethyl methacrylate) (PEO-b-PDPA) copolymers as micelle cores to carry hydrophobic substances were also synthesized through atom transfer radical polymerization (ATRP). An injectable hydrogel composite system was finally obtained by mixing CMC-NH2 and CMC-CHO polymer suspensions containing PEO-b-PDPA copolymer micelles through a Schiff base reaction. This newly-synthesized, tunable, cellulose-based double barrier system exhibits a pH-triggered, prolonged, and slow-release profile based on the release test using both Nile Red dye and doxorubicin. The hydrogel system also exhibited comparable storage moduli and tunable degradation properties.


Asunto(s)
Carboximetilcelulosa de Sodio , Doxorrubicina/administración & dosificación , Sistemas de Liberación de Medicamentos/métodos , Hidrogeles , Polímeros , Carboximetilcelulosa de Sodio/química , Carboximetilcelulosa de Sodio/farmacología , Células HeLa , Humanos , Hidrogeles/química , Hidrogeles/farmacología , Concentración de Iones de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Micelas , Polimerizacion , Polímeros/química , Polímeros/farmacología
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