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1.
Inorg Chem ; 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33821639

RESUMO

Materials capable of generating coherent short-wave (<300 nm) light have attracted extensive scientific and technical interest due to their wide utilization in laser research. In this study, a the rare-earth-metal sulfate NaCe(SO4)2(H2O) (NCSO) was synthesized through a hydrothermal method, while NaBi(SO4)2(H2O) (NBSO) was successfully obtained via a homovalent cation substitution of the parent compound NCSO under hydrothermal conditions. The space groups of crystalline NCSO and NBSO are P3121 and P3221, respectively. Both compounds have similar connectivities which feature a three-dimensional channel structure formed by asymmetric [CeO9]15-/[BiO9]15- tricapped trigonal prisms and distorted [SO4]2- tetrahedra. The introduction of Bi3+ with larger ionic radii and stereochemically active lone-pair electrons simultaneously enhanced the SHG effect and band gap of NBSO in comparison to its parent compound NCSO. In contrast to NCSO, which possesses a narrow energy band gap (2.46 eV), NBSO displays the largest energy band gap (4.54 eV) among the reported bismuth sulfate NLO materials. Powder frequency-doubling-effect measurements exhibit that NCSO and NBSO possess phase-matchable SHG responses of 0.2 × KDP and 0.38 × KDP at 1064 nm, respectively. Theoretical studies have been implemented to further elucidate the structure-performance relationships of the two compounds. Experimental and theoretical studies both demonstrate that NBSO may be a promising nonlinear material applied in the short-wavelength region.

2.
Artigo em Inglês | MEDLINE | ID: mdl-33822447

RESUMO

Wide ultraviolet (UV) transparency, strong second-harmonic generation (SHG) response, and sufficient optical birefringence for phase-matching (PM) at short SHG wavelengths are three vital prerequisites for practical UV nonlinear optical (NLO) materials. However, simultaneously optimizing these properties remains a major challenge, particularly for metal phosphates, due to their competing requirements. Herein, we report a non-traditional π-conjugated cation-based UV NLO phosphate [C(NH2)3]6(PO4)2·3H2O (GPO) with a short UV cutoff edge. Remarkably, GPO is not only SHG active at 1064 nm (3.8 × KH2PO4 @ 1064 nm) and 532 nm (0.3 × ß -BaB2O4 @ 532 nm), but it also possesses the largest birefringence (0.078 @ 546 nm) among phosphates with a band gap exceeding 6.0 eV. The PM SHG capability of GPO can extend to 250 nm, indicating GPO is a promising UV solar-blind NLO material. Theoretical calculations and crystal structure analysis demonstrate that the rare coexistence of wide UV transparency, large SHG response and optical anisotropy can be attributed to the introduction of the π-conjugated cations [C(NH2)3]+ and their favorable arrangement with [PO4]3- anions.

3.
Artigo em Inglês | MEDLINE | ID: mdl-33825459

RESUMO

Li-rich cathode materials possess a much higher theoretical energy density than all intercalated cathode materials currently reported and thus are considered as the most promising candidate for next-generation high-energy density Li-ion batteries. However, the rapid voltage decay and the irreversible phase transition of O3-type Li-rich cathode materials often lessen their actual energy density and limit their practical applications, and thus, effectively suppressing the voltage decay of Li-rich cathodes becomes the hotspot of the current research. Herein, the F-doped O2-type Li-rich cathode materials Li1.2Mn0.54Ni0.13Co0.13O2+δ-xFx (F-O2-LRO) are designed and prepared based on the P2-type sodium-ion cathode materials Na5/6Li1/4(Mn0.54Ni0.13Co0.13)3/4O2+δ (Na-LRO) by ion exchange. It has been found that the as-prepared F-O2-LRO exhibits excellent electrochemical performance, for example, a high discharge specific capacity of 280 mA h g-1 at 0.1 C with an initial Coulombic efficiency of 94.4%, which is obviously higher than the original LRO (77.2%). After 100 cycles, the F-O2-LRO cathode can still maintain a high capacity retention of 95% at a rate of 1 C, while the capacity retention of the original LRO is only 69.1% at the same current rate. Furthermore, the voltage difference (ΔV) of F-O2-LRO before and after cycling is only 0.268 V after 100 cycles at 1 C, which is less than that of the LRO cathode (0.681 V), indicating much lower polarization. Besides, even at a high current rate of 5 C, F-O2-LRO still displays a satisfactory discharge capacity of 210 mA h g-1 with a capacity retention of 90.1% after 100 cycles. Therefore, this work put forward a new strategy for the development and industrial application of Li-rich cathode materials in high-energy Li-ion batteries.

4.
Orthop Surg ; 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33826254

RESUMO

OBJECTIVE: To develop and validate the efficacy of a 3D-printed screw-rod auxiliary system for unstable atlas fractures. METHODS: This research is a retrospective analysis, and a total of 14 patients, including 11 males and three females, were enrolled in our hospital from January 2017 to March 2019 who underwent occipitocervical fusion assisted by the 3D-printed screw-rod auxiliary system were reviewed, and with an average age of 53.21 ± 14.81 years, an average body mass index (BMI) of 23.61 ± 1.93 kg/m2 . The operation time, blood loss and radiation times during the operation were recorded. The maximum fracture displacement values of pre- and post-operation were measured based on CT imaging. All screw grades were evaluated after surgery. The occipital-cervical 2 (O-C2 ) angle and occipitocervical inclination (OCI) angle of pre-operation, post-operation and the last following-up were measured. The dysphagia scale 3 months after surgery and at the last follow-up, the Neck Disability Index (NDI) 3 months after surgery and at the last follow-up were assessed. RESULTS: All patients were completed the surgery successfully. There was no patient with severe dysphagia or aggravation of nerve injury. The follow-up was from 12 to 14 months, and with an average of 12.5 months. The average surgery time, average blood loss and average radiation times for the 14 patients were 112.14 min, 171.43 mL and 5.07 times, respectively. There was a significant difference in maximum fracture displacement between pre- and post-operation values (P < 0.05). A total of 56 screws were inserted in 14 patients, among them, three screws were classified as grade 1, and the other screws were classified as grade 0. There was a significant difference in the O-C2 between pre-operation and 3 days after operation (P = 0.002); There was a significant difference in OCI angles between pre-operation and 3 days after operation (P < 0.05); there was no significant difference in the O-C2 or OCI angle between 3 days after the operation and the last follow-up (P = 0.079; P = 0.201). The dysphagia scales of two patients were assessed as mild at 3 months after surgery, and the others were assessed as normal at 3 months after surgery. All patients' dysphagia scores returned to normal at the last follow-up. The average NDI and average neck Visual Analogue Scale (VAS) scores at the last follow-up were 2.53 and 8.41, respectively. CONCLUSION: It can objectively restore the OCI to normal with few post-operative complications under the assistance of a screw-rod auxiliary system to perform occipitocervical fusion for unstable atlas fractures and atlantooccipital joint instability.

5.
Proc Natl Acad Sci U S A ; 118(16)2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33846258

RESUMO

Macrophages are the key regulator of T-cell responses depending on their activation state. C-C motif chemokine receptor-like 2 (CCRL2), a nonsignaling atypical receptor originally cloned from LPS-activated macrophages, has recently been shown to regulate immune responses under several inflammatory conditions. However, whether CCRL2 influences macrophage function and regulates tumor immunity remains unknown. Here, we found that tumoral CCRL2 expression is a predictive indicator of robust antitumor T-cell responses in human cancers. CCRL2 is selectively expressed in tumor-associated macrophages (TAM) with immunostimulatory phenotype in humans and mice. Conditioned media from tumor cells could induce CCRL2 expression in macrophages primarily via TLR4, which is negated by immunosuppressive factors. Ccrl2 -/- mice exhibit accelerated melanoma growth and impaired antitumor immunity characterized by significant reductions in immunostimulatory macrophages and T-cell responses in tumor. Depletion of CD8+ T cells or macrophages eliminates the difference in tumor growth between WT and Ccrl2 -/- mice. Moreover, CCRL2 deficiency impairs immunogenic activation of macrophages, resulting in attenuated antitumor T-cell responses and aggravated tumor growth in a coinjection tumor model. Mechanically, CCRL2 interacts with TLR4 on the cell surface to retain membrane TLR4 expression and further enhance its downstream Myd88-NF-κB inflammatory signaling in macrophages. Similarly, Tlr4 -/- mice exhibit reduced CCRL2 expression in TAM and accelerated melanoma growth. Collectively, our study reveals a functional role of CCRL2 in activating immunostimulatory macrophages, thereby potentiating antitumor T-cell response and tumor rejection, and suggests CCLR2 as a potential biomarker candidate and therapeutic target for cancer immunotherapy.

6.
Cereb Cortex ; 2021 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-33822906

RESUMO

Wnt/ß-catenin signaling plays multiple important roles during mammalian brain development, and it regulates the proliferation and differentiation of neural progenitors in a context-dependent manner and affects neocortex layer formation. However, the specific role of Wnt/ß-catenin in neuronal layer fate determination in the neocortex is still unclear. Here, we report that Zbed3, which is a positive regulator of Wnt/ß-catenin signaling, colocalizes with ß-catenin at the endfeet of radial glia in the ventricular zone of embryo mouse neocortex. Overexpression and knockdown of Zbed3 increased and decreased the activity of Wnt/ß-catenin signaling in the neocortex, respectively. Interestingly, knockdown of Zbed3 in vivo could significantly shift neuronal fates from deep layers to upper layers but is not required for the proliferation and differentiation of neural progenitors. Overexpression of Zbed3 led to increased generation of deep-layer neurons without impairing cell cycle exit of neural progenitors. More importantly, knockdown of Zbed3 could effectively block the effects of the ectopic expression of stabilized ß-catenin on neocortex layer formation. Hence, our results demonstrate that Zbed3 is indispensable for Wnt/ß-catenin signaling regulating neuronal layer fates in the developing brain.

7.
J Viral Hepat ; 2021 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-33797145

RESUMO

A substantial proportion of patients with chronic hepatitis B (CHB) who do not fit into any of the usual immune states are considered to be in the "gray zones ". We aimed to investigate the distribution and characteristics of this gray zone in a large cohort of CHB patients. Four thousand seven hundred and fifty-nine consecutive treatment-naïve CHB patients were enrolled. The immune states were defined based on AASLD 2018 Hepatitis B Guidance. Gray zone CHB patients were classified into 4 groups: HBeAg positive, normal ALT levels, and serum HBV DNA ≤ 106 IU/mL (GZ-A); HBeAg positive, elevated ALT levels and serum HBV DNA ≤ 2×104 IU/mL (GZ-B); HBeAg negative, normal ALT levels and serum HBV DNA ≥ 2×103 IU/mL (GZ-C); HBeAg negative, elevated ALT levels and serum HBV DNA ≤ 2×103 IU/mL (GZ-D). The distributions of different immune states were: 233 (4.90%) patients in immune-tolerant phase, 941 (19.77%) patients in HBeAg-positive immune active phase, 1,717 (36.08%) patients in inactive phase and 546 (11.47%) patients in HBeAg-negative immune active phase. Of note, 1,322 (27.78%) patients did not fit into any of above phases and were defined as the gray zone. A high proportion of patients in GZ-B had advanced fibrosis (33.3%) or cirrhosis (25.8%). Older age, HBeAg positive status and higher ALT levels were independently risk factors of advanced disease in gray zone CHB patients. Therefore, our results revealed that more than a quarter of CHB patients were classified into the gray zone and a high proportion of patients in GZ-B had advanced fibrosis or even cirrhosis.

9.
Biology (Basel) ; 10(3)2021 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-33810062

RESUMO

Currently, there is scant information about the biodiversity and functional diversity of microbes in the eastern Indian Ocean (EIO). Here, we used a combination of high-throughput sequencing of 16S rRNA genes and a metagenomic approach to investigate the microbial population structure and its metabolic function in the equatorial EIO. Our results show that Cyanobacterial Prochlorococcus made up the majority of the population. Interestingly, there were fewer contributions from clades SAR11 (Alphaproteobacteria) and SAR86 (Gammaproteobacteria) to microbial communities than contributions from Prochlorococcus. Based on functional gene analysis, functional genes rbcL, narB, and nasA were relatively abundant among the relevant genes. The abundance of Prochlorococcus implies its typically ecological adaptation in the local ecosystem. The microbial metabolic potential shows that in addition to the main carbon fixation pathway Calvin cycle, the rTCA cycle and the 3-HP/4-HB cycle have potential alternative carbon fixation contributions to local ecosystems. For the nitrogen cycle, the assimilatory nitrate and nitrite reduction pathway is potentially the crucial form of nitrogen utilization; unexpectedly, nitrogen fixation activity was relatively weak. This study extends our knowledge of the roles of microbes in energy and resource cycling in the EIO and provides a foundation for revealing profound biogeochemical processes driven by the microbial community in the ocean.

10.
Nanotechnology ; 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33794512

RESUMO

With the incorporation of carbon nanotubes (CNTs), the CNT/Polypropylene (PP) composites are found to possess enhanced mechanical properties, but the reinforcing effect of CNT weakens at high-percentage addition due to the CNT aggregation. To optimize the properties of nanocomposite, it requires a fundamental understanding of the effect of CNT dispersion on the nanocomposite. In this work, the coarse-grained molecular models of CNT/PP nanocomposites are constructed, which consist of randomly dispersed or aggregated CNT bundles. Our simulation reveals that with randomly dispersed CNT bundles, the nanocomposite shows continuously improved properties with increasing CNT contents due to the effective CNT/PP interface and reinforcing effect of CNT. Comparatively, the nanocomposites with aggregated CNT clusters exhibit a decline in the yield strength at CNT contents over 3 wt%, which is resulted from the reduced CNT load-carrying capacity due to the formation of structural voids in the interfacial region. This study achieves the in-situ observation of the structural voids evolution of nanocomposites under loading and provides valuable insights into the effect of CNT dispersion on the reinforcement of CNT/PP composites, which paves the way for the optimized design of nanocomposite materials with superior mechanical properties by designing the CNT dispersion in the nanocomposite.

11.
Emerg Microbes Infect ; 10(1): 664-676, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33734013

RESUMO

Seasonal human coronaviruses (HCoVs) including HCoV-229E, -OC43, -NL63, and -HKU1 widely spread in global human populations. However, the relevance of humoral response against seasonal HCoVs to COVID-19 pathogenesis is elusive. In this study, we profiled the temporal changes of IgG antibody against spike proteins (S-IgG) of SARS-CoV-2 and seasonal HCoVs in 838 plasma samples collected from 344 COVID-19 patients. We tested the antigenic cross-reactivities of S protein between SARS-CoV-2 and seasonal HCoVs and evaluated the correlations between the levels of HCoV-OC43 S-IgG and the disease severity in COVID-19 patients. We found that SARS-CoV-2 S-IgG titres mounted until days 22-28, whereas HCoV-OC43 antibody titres increased until days 15-21 and then plateaued until day 46. However, IgG titres against HCoV-NL63, -229E, and -HKU1 showed no significant increase. A two-way cross-reactivity was identified between SARS-CoV-2 and HCoV-OC43. Neutralizing antibodies against SARS-CoV-2 were not detectable in healthy controls who were positive for HCoV-OC43 S-IgG. HCoV-OC43 S-IgG titres were significantly higher in patients with severe disease than those in mild patients at days 1-21 post symptom onset (PSO). Higher levels of HCoV-OC43 S-IgG were also observed in patients requiring mechanical ventilation. At days 1-10 PSO, HCoV-OC43 S-IgG titres correlated to disease severity in the age group over 60. Our data indicate that there is a correlation between cross-reactive antibody against HCoV-OC43 spike protein and disease severity in COVID-19 patients.


Assuntos
Anticorpos Antivirais/sangue , Coronavirus Humano OC43/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Reações Cruzadas/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Adulto Jovem
12.
Food Chem ; 351: 129344, 2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-33647688

RESUMO

Protein oxidation is considered as an important factor affecting the texture quality of surimi. In this work, the myofibrillar protein (MP) from shrimp (Penaeus vannamei) was subjected to a hydroxyl radical generating system at various concentrations of H2O2, to simulate the oxidative environment during surimi processing. After the hydroxyl radical oxidation, it was found that the carbonyl content, surface hydrophobicity, and MP aggregation increased. Meanwhile, the a-helix decreased, but ß-sheet increased after oxidation. The moderate oxidation led to a dense network microstructure, increased water holding capacity (WHC) and decreased water mobility, which ultimately enhanced textural (hardness and springiness increased by 0.51- and 0.06-fold, respectively) and rheological properties of MP gel (MPG). However, excessive oxidation could reduce the mechanical properties of MPG. The microstructure, WHC and water distribution played a key role in the mechanical properties of MPG. This study can provide a theoretical basis for processing of shrimp surimi products.


Assuntos
Anostraca , Fenômenos Químicos , Radical Hidroxila/química , Proteínas Musculares/química , Animais , Géis , Interações Hidrofóbicas e Hidrofílicas , Oxirredução , Reologia , Alimentos Marinhos , Água/química
13.
Ann Palliat Med ; 10(2): 2167-2174, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33725772

RESUMO

BACKGROUND: In March 2020, the World Health Organization (WHO) declared COVID-19 a public health emergency of international concern. A small proportion of patients infected with COVID-19 go on to develop pneumonia. We speculated that COVID-19 may be likely to result in psychological disorders such as anxiety and depression. In this study, we conducted an investigation of anxiety and depression in patients with COVID-19. METHODS: Sixty-five COVID-19 patients were randomly enrolled into this study. Anxiety and depression among participants were measured through the completion of anonymous Chinese-language Zung self-rating anxiety scale and self-rating depression scale questionnaires. Data were analyzed using independent samples t-tests, Mann-Whitney U-tests, and χ2 tests. RESULTS: The questionnaire results showed that 26.15% and 41.54% of participants suffered from anxiety and depression, respectively, although there was no significantly statistical difference between the proportions of COVID-19 patients with anxiety and depression. Statistically significant differences in employment status, partial pressure of oxygen, and corticosteroid application existed between moderate- and severe COVID-19 patients (P<0.05). In particular, the partial pressure of oxygen was significantly lower in severe COVID-19 patients than in their moderate counter parts (71.31±23.54 vs. 101.06±34.43, U=156, P=0.006). Total lymphocytes was lower in severe group than in moderate group [1.659±0.643 vs. 0.745 (0.645, 0.928), U=109, P=0.000]. Also, a higher proportion of female than male patients had anxiety (χ2=5.388, P=0.02). COVID-19 patients who received antiviral medications also displayed a higher rate of anxiety (χ2=4.481, P=0.034). Total lymphocytes between the non-anxiety and anxiety had statistical difference (U=321, P=0.019). Meanwhile, total lymphocytes between the non-depression and depression also had statistical difference (U=389.5, P=0.01). CONCLUSIONS: Among patients with COVID-19, females and those treated with antiviral medications were more likely to experience anxiety. In addition, our findings reflected the effect of anxiety and depression on immune system.


Assuntos
Ansiedade/epidemiologia , Depressão/epidemiologia , Antivirais/uso terapêutico , China , Estudos Transversais , Feminino , Humanos , Linfócitos/citologia , Masculino , Inquéritos e Questionários
14.
Acta Biomater ; 2021 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-33722788

RESUMO

Spinal cord injury (SCI) causes immune activation of resident macrophages/microglia. Activated macrophages/microglia have two different phenotypes, the pro-inflammatory classically activated (M1) phenotype and the anti-inflammatory alternatively activated (M2) phenotype. M1 phenotype macrophages/microglia are the key factor in inflammation. The treatment of SCI remains a huge challenge due to the nontargeting and inefficiency of anti-inflammatory drugs through the blood-brain barrier (BBB). The purpose of this experiment was to design M2-type primary peritoneal macrophages exosomes (Exos) as a drug carrier for berberine (Ber), which can be efficiently targeted to deliver drugs to the injured spinal cord due to the natural advantage of Exos across the BBB. The Exos with particle size of 125±12 nm were loaded with by an ultrasonic method and the drug loading reached 17.13 ±1.64%. The Ber release experiment showed that the loaded sample (Exos-Ber) exhibited sustained release effect, and the cumulative release amount reached 71.44±2.86% within 48 h. In vitro and in vivo experiments confirmed that the Exos-Ber could decrease the M1 protein marker iNOS, elevate the M2 protein marker CD206 and reduce inflammatory and apoptotic cytokines (TNF-α, IL-1ß, IL-6, Caspase 9, Caspase 8), which showed that Exos-Ber had a good anti-inflammatory and anti-apoptotic effect by inducing macrophages/microglia from the M1 phenotype to M2 phenotype polarization. Moreover, the motor function of SCI mice was significantly improved after Exos-Ber treatment, indicating that Exos-Ber is a potential agent for SCI therapy. STATEMENT OF SIGNIFICANCE: Efficient targeting strategy for drug delivery. In addition to good biocompatibility and stealth ability, M2 macrophage-derived Exosomes present natural inflammatory targeting ability. The inflammatory microenvironment after spinal cord injury provides motivation for the targeting of exosomes. Natural drug carrier with higher safety. With the rapid development of nanomaterials, drug carriers have become more selective. However, due to the special microenvironment after central nervous system damage, some non-degradable inorganic materials will increase the pressure of self-healing and even secondary damage to neurons, which has been solved by the emergence of exosomes. Some previous studies used tumor cell line exosomes as drug carriers, but the carcinogenic factors carried by themselves have extremely high hidden dangers, and endogenous macrophage exosomes have absolute advantages over their safety.

15.
Lancet ; 397(10279): 1075-1084, 2021 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-33743869

RESUMO

BACKGROUND: Wuhan was the epicentre of the COVID-19 outbreak in China. We aimed to determine the seroprevalence and kinetics of anti-SARS-CoV-2 antibodies at population level in Wuhan to inform the development of vaccination strategies. METHODS: In this longitudinal cross-sectional study, we used a multistage, population-stratified, cluster random sampling method to systematically select 100 communities from the 13 districts of Wuhan. Households were systematically selected from each community and all family members were invited to community health-care centres to participate. Eligible individuals were those who had lived in Wuhan for at least 14 days since Dec 1, 2019. All eligible participants who consented to participate completed a standardised electronic questionnaire of demographic and clinical questions and self-reported any symptoms associated with COVID-19 or previous diagnosis of COVID-19. A venous blood sample was taken for immunological testing on April 14-15, 2020. Blood samples were tested for the presence of pan-immunoglobulins, IgM, IgA, and IgG antibodies against SARS-CoV-2 nucleocapsid protein and neutralising antibodies were assessed. We did two successive follow-ups between June 11 and June 13, and between Oct 9 and Dec 5, 2020, at which blood samples were taken. FINDINGS: Of 4600 households randomly selected, 3599 families (78·2%) with 9702 individuals attended the baseline visit. 9542 individuals from 3556 families had sufficient samples for analyses. 532 (5·6%) of 9542 participants were positive for pan-immunoglobulins against SARS-CoV-2, with a baseline adjusted seroprevalence of 6·92% (95% CI 6·41-7·43) in the population. 437 (82·1%) of 532 participants who were positive for pan-immunoglobulins were asymptomatic. 69 (13·0%) of 532 individuals were positive for IgM antibodies, 84 (15·8%) were positive for IgA antibodies, 532 (100%) were positive for IgG antibodies, and 212 (39·8%) were positive for neutralising antibodies at baseline. The proportion of individuals who were positive for pan-immunoglobulins who had neutralising antibodies in April remained stable for the two follow-up visits (162 [44·6%] of 363 in June, 2020, and 187 [41·2%] of 454 in October-December, 2020). On the basis of data from 335 individuals who attended all three follow-up visits and who were positive for pan-immunoglobulins, neutralising antibody levels did not significantly decrease over the study period (median 1/5·6 [IQR 1/2·0 to 1/14·0] at baseline vs 1/5·6 [1/4·0 to 1/11·2] at first follow-up [p=1·0] and 1/6·3 [1/2·0 to 1/12·6] at second follow-up [p=0·29]). However, neutralising antibody titres were lower in asymptomatic individuals than in confirmed cases and symptomatic individuals. Although titres of IgG decreased over time, the proportion of individuals who had IgG antibodies did not decrease substantially (from 30 [100%] of 30 at baseline to 26 [89·7%] of 29 at second follow-up among confirmed cases, 65 [100%] of 65 at baseline to 58 [92·1%] of 63 at second follow-up among symptomatic individuals, and 437 [100%] of 437 at baseline to 329 [90·9%] of 362 at second follow-up among asymptomatic individuals). INTERPRETATION: 6·92% of a cross-sectional sample of the population of Wuhan developed antibodies against SARS-CoV-2, with 39·8% of this population seroconverting to have neutralising antibodies. Our durability data on humoral responses indicate that mass vaccination is needed to effect herd protection to prevent the resurgence of the epidemic. FUNDING: Chinese Academy of Medical Sciences & Peking Union Medical College, National Natural Science Foundation, and Chinese Ministry of Science and Technology. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.


Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , /imunologia , Adolescente , Adulto , Idoso , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , /epidemiologia , Criança , Pré-Escolar , China/epidemiologia , Estudos Transversais , Feminino , Seguimentos , Humanos , Imunidade Coletiva/imunologia , Imunidade Humoral , Lactente , Recém-Nascido , Estudos Longitudinais , Masculino , Vacinação em Massa/organização & administração , Pessoa de Meia-Idade , Estudos Soroepidemiológicos , Adulto Jovem
16.
Sci Rep ; 11(1): 5022, 2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-33658578

RESUMO

We hypothesized that epigenetics is a link between smoking/allergen exposures and the development of Asthma and chronic obstructive pulmonary disease (ACO). A total of 75 of 228 COPD patients were identified as ACO, which was independently associated with increased exacerbations. Microarray analysis identified 404 differentially methylated loci (DML) in ACO patients, and 6575 DML in those with rapid lung function decline in a discovery cohort. In the validation cohort, ACO patients had hypermethylated PDE9A (+ 30,088)/ZNF323 (- 296), and hypomethylated SEPT8 (- 47) genes as compared with either pure COPD patients or healthy non-smokers. Hypermethylated TIGIT (- 173) gene and hypomethylated CYSLTR1 (+ 348)/CCDC88C (+ 125,722)/ADORA2B (+ 1339) were associated with severe airflow limitation, while hypomethylated IFRD1 (- 515) gene with frequent exacerbation in all the COPD patients. Hypermethylated ZNF323 (- 296) / MPV17L (+ 194) and hypomethylated PTPRN2 (+ 10,000) genes were associated with rapid lung function decline. In vitro cigarette smoke extract and ovalbumin concurrent exposure resulted in specific DNA methylation changes of the MPV17L / ZNF323 genes, while 5-aza-2'-deoxycytidine treatment reversed promoter hypermethylation-mediated MPV17L under-expression accompanied with reduced apoptosis and decreased generation of reactive oxygen species. Aberrant DNA methylations may constitute a determinant for ACO, and provide a biomarker of airflow limitation, exacerbation, and lung function decline.

17.
Small ; : e2007578, 2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-33656277

RESUMO

Sodium metal is regarded as one of the most prospective next-generation anodes material owing to its high theoretical capacity, low redox potential, low cost, and natural abundance. Its most notable problem is the dendrite growth during Na plating/striping, which causes not only the safety concern but also the generation of inactive Na. Here, it is demonstrated that 2D carbon nanosheets embedded by bismuth nanoparticles (NPs) (denoted as Bi⊂CNs) serve as a robust nucleation buffer layer to endow the sodium metal anodes (SMAs) with high Coulombic efficiencies (CEs) and dendrite-free deposition during long-term cycling. The embedded Bi nanoparticles significantly reduce the nucleation barrier through the "sodiophilic" Na-Bi alloy. Meanwhile, the carbon frameworks effectively circumvent the gradual failure of those Na-Bi nucleation sites. As a result, the metallic Na on the Bi⊂CNs nucleation layer is repeatedly plated/stripped for nearly 7700 h (1287 cycles) at 3 mA h cm-2 with an average CE of 99.92%. Moreover, the Na||Na symmetric cells with the Bi⊂CNs buffer layer are stably plated/stripped for 4000 h at 1 mA cm-2 and 1 mA h cm-2 . It is found that the cycling stability is closely related to the Na utilization of SMAs and current rate.

18.
Front Endocrinol (Lausanne) ; 12: 609308, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33716967

RESUMO

Thyroid hormones mediate a remarkable range of functions in many tissues and organ systems through the thyroid hormone receptors-THRA and THRB. Tissues and organs are composed of heterogeneous cells of different cell types. These different cell types have varying receptor expression abilities, which lead to variable responses in thyroid hormone regulation. The tissue-specific Thra and Thrb gene expression patterns help us understand the action of thyroid hormones at the tissue level. However, the situation becomes complicated if we wish to focus on tissues more closely to trace the responsive cells, which is a vital step in the process of understanding the molecular mechanism of diseases related to thyroid hormone regulation. Single-cell RNA sequencing technology is a powerful tool used to profile gene expression programs in individual cells. The Tabula Muris Consortium generates a single-cell transcriptomic atlas across the life span of Mus musculus that includes data from 23 tissues and organs. It provides an unprecedented opportunity to understand thyroid hormone regulation at the cell type resolution. We demonstrated the approaches that allow application of the single-cell RNA-Seq data generated by the Tabula Muris Consortium to trace responsive cells in tissues. First, employing the single-cell RNA-Seq data, we calculated the ability of different cell types to express Thra and Thrb, which direct us to the cell types sensitive to thyroid hormone regulation in tissues and organs. Next, using a cell clustering algorithm, we explored the subtypes with low Thra or Thrb expression within the different cell types and identified the potentially responsive cell subtypes. Finally, in the liver tissue treated with thyroid hormones, using the single-cell RNA-Seq data, we successfully traced the responsive cell types. We acknowledge that the computational predictions reported here need to be further validated using wet-lab experiments. However, we believe our results provide powerful information and will be beneficial for wet lab researchers.

19.
Cleve Clin J Med ; 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33687984

RESUMO

An effective vaccine is considered the best method to achieve herd immunity. As of February 2021, 12 vaccines were in late-stage clinical trials worldwide, with many more in development. Of those, 8 have received emergency use authorization from at least one country's governing body. These vaccines use various platforms to deliver the vaccines, each with pros and cons. Published data show these vaccines are effective in preventing the severe symptoms associated with COVID-19 in adults with few side effects, but challenges remain with storage and delivery and treating virus variants.

20.
J Agric Food Chem ; 69(10): 3015-3025, 2021 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-33685122

RESUMO

Developing liquid systems with high protein contents is drawing intensive attention; however, this is challenged by heat-induced aggregation and gelation of proteins. Herein, we described a facile but robust approach of combined preheating and ultrasonic treatment (CPUT) to fabricate soy protein particles (SPPs) with enhanced heat stability. Results showed that these heat-stable particles, upon reheating at 1% (w/v), showed antiaggregation property evidenced from no obvious changes of the particle size distributions of suspensions. Besides, no gelation was found in the reheated test for SPPs suspended even at a concentration of 10% (w/v). In contrast, the control formed sol-gel after heating. The rearrangements of soy protein molecules by CPUT led to the formation of SPPs with reduced surface energy, which was primarily responsible for their heat stability. These findings highlighted that the CPUT could prepare thermally stable soy proteins, providing insights into the application of soy proteins in protein-enriched beverages.

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