Publications by authors named "Qiao Wang"

528 Publications

Molecular mechanism of interaction between SARS-CoV-2 and host cells and interventional therapy.

Signal Transduct Target Ther 2021 Jun 11;6(1):233. Epub 2021 Jun 11.

College of Life Sciences, Hebei Agricultural University, Baoding, China.

The pandemic of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has resulted in an unprecedented setback for global economy and health. SARS-CoV-2 has an exceptionally high level of transmissibility and extremely broad tissue tropism. However, the underlying molecular mechanism responsible for sustaining this degree of virulence remains largely unexplored. In this article, we review the current knowledge and crucial information about how SARS-CoV-2 attaches on the surface of host cells through a variety of receptors, such as ACE2, neuropilin-1, AXL, and antibody-FcγR complexes. We further explain how its spike (S) protein undergoes conformational transition from prefusion to postfusion with the help of proteases like furin, TMPRSS2, and cathepsins. We then review the ongoing experimental studies and clinical trials of antibodies, peptides, or small-molecule compounds with anti-SARS-CoV-2 activity, and discuss how these antiviral therapies targeting host-pathogen interaction could potentially suppress viral attachment, reduce the exposure of fusion peptide to curtail membrane fusion and block the formation of six-helix bundle (6-HB) fusion core. Finally, the specter of rapidly emerging SARS-CoV-2 variants deserves a serious review of broad-spectrum drugs or vaccines for long-term prevention and control of COVID-19 in the future.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41392-021-00653-wDOI Listing
June 2021

Synthesis, Crystal Structure, Herbicidal Activity, and SAR Study of Novel -(Arylmethoxy)-2-chloronicotinamides Derived from Nicotinic Acid.

J Agric Food Chem 2021 Jun 4. Epub 2021 Jun 4.

College of Chemical Engineering, Zhejiang University of Technology, Hangzhou 310014, China.

Nicotinic acid, also known as niacin, is a natural product, which is widely found in plants and animals. To discover novel natural-product-based herbicides, a series of -(arylmethoxy)-2-chloronicotinamides were designed and synthesized. Some of the new -(arylmethoxy)-2-chloronicotinamides exhibited excellent herbicidal activity against (bentgrass) at 100 μM. Compound (2-chloro--((3,4-dichlorobenzyl)oxy)nicotinamide) possessed excellent herbicidal activity against (duckweed), with an IC value of 7.8 μM, whereas the commercial herbicides clomazone and propanil had values of 125 and 2 μM, respectively. The structure-activity relationships reported in this paper could be used for the development of new herbicides against monocotyledonous weeds.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.jafc.0c07538DOI Listing
June 2021

Electromagnetically Induced Transparency-Like Effect by Dark-Dark Mode Coupling.

Nanomaterials (Basel) 2021 May 20;11(5). Epub 2021 May 20.

Department of Physics, Dalian University of Technology, Ganjingzi District, Dalian 116024, China.

Electromagnetically induced transparency-like (EIT-like) effect is a promising research area for applications of slow light, sensing and metamaterials. The EIT-like effect is generally formed by the destructive interference of bright-dark mode coupling and bright-bright mode coupling. There are seldom reports about EIT-like effect realized by the coupling of two dark modes. In this paper, we numerically and theoretically demonstrated that the EIT-like effect is achieved through dark-dark mode coupling of two waveguide resonances in a compound nanosystem with metal grating and multilayer structure. If we introduce |1⟩, |2⟩ and |3⟩ to represent the surface plasmon polaritons (SPPs) resonance, waveguide resonance in layer 2, and waveguide resonance in layer 4, the destructive interference occurs between two pathways of |0⟩→|1⟩→|2⟩ and |0⟩→|1⟩→|2⟩→|3⟩→|2⟩, where |0⟩ is the ground state without excitation. Our work will stimulate more studies on EIT-like effect with dark-dark mode coupling in other systems.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/nano11051350DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8161169PMC
May 2021

Simulation Verification of Barrierless HONO Formation from the Oxidation Reaction System of NO, Cl, and Water in the Atmosphere.

Environ Sci Technol 2021 May 21. Epub 2021 May 21.

Environment Research Institute, Shandong University, Qingdao 266237, P. R. China.

Nitrous acid (HONO) is a major source of hydroxyl (OH) radicals, and identifying its source is crucial to atmospheric chemistry. Here, a new formation route of HONO from the reaction of NO with Cl radicals with the aid of one or two water molecules [(Cl) (NO) (HO) ( = 1-2)] as well as on the droplet surface was found by Born-Oppenheimer molecular dynamic simulation and metadynamic simulation. The (Cl) (NO) (HO) (monohydrate) system exhibited a free-energy barrier of approximately 0.95 kcal mol, whereas the (Cl) (NO) (HO) (dihydrate) system was barrierless. For the dihydrate system and the reaction of NO with Cl radicals on the droplet surface, only one water molecule participated in the reaction and the other acted as the "solvent" molecule. The production rates of HONO suggested that the monohydrate system ([NO] = 8.56 × 10 molecule cm, [Cl] = 8.00 × 10 molecule cm, [HO] = 5.18 × 10 molecule cm) could account for 40.3% of the unknown HONO production rate () at site 1 and 53.8% of at site 2 in the East China Sea. This study identified the importance of the reaction system of NO, Cl, and water molecules in the formation of HONO in the marine boundary layer region.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.est.1c01773DOI Listing
May 2021

Potential Aphid Population Regulation by Aphidius colemani (Hymenoptera: Aphidiidae) in Response to Host Density, Parasitoid Density, and Age.

J Econ Entomol 2021 May 18. Epub 2021 May 18.

School of Agriculture and Environment, Massey University, Private Bag 11222, Palmerston North, New Zealand.

Aphidius colemani Viereck is an important parasitoid of green peach aphid [Myzus persicae (Sulzer)], a serious pest of greenhouse crops. Augmentation of natural enemies is the most used approach to biological control of greenhouse pests. Yet, the optimal release time, rate, and age of natural enemies are often unclear. Here we tested the influence of population density of both A. colemani and M. persicae, as well as parasitoid age, on parasitism and sex allocation. We aim is to provide information for cost-effective aphid biological control programs. We show that 1) parasitoid females increased parasitism and produced more female-biased offspring with an increase of aphid density, 2) a moderate increase of parasitoid release rate elevated parasitism and daughter production when aphid density was high, 3) parasitism rate declined with an increase of aphid density but the moderate increase of parasitoid release rate eased the decline rate, and 4) 3-d-old parasitoids parasitized more aphids than younger ones but parasitoid age had no effect on daughter production. These findings suggest that A. colemani females can adjust their ability to regulate the aphid population in response to aphid population dynamics. In augmentative programs, a moderate increase of parasitoid release when aphid density is high could achieve effective control and a release of 3-d-old parasitoids could lead to a better control outcome.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/jee/toab090DOI Listing
May 2021

Rapid isolation and immune profiling of SARS-CoV-2 specific memory B cell in convalescent COVID-19 patients via LIBRA-seq.

Signal Transduct Target Ther 2021 05 17;6(1):195. Epub 2021 May 17.

School of Public Health (Shenzhen), Sun Yat-sen University, Shenzhen, China.

B cell response plays a critical role against SARS-CoV-2 infection. However, little is known about the diversity and frequency of the paired SARS-CoV-2 antigen-specific BCR repertoire after SARS-CoV-2 infection. Here, we performed single-cell RNA sequencing and VDJ sequencing using the memory and plasma B cells isolated from five convalescent COVID-19 patients, and analyzed the spectrum and transcriptional heterogeneity of antibody immune responses. Via linking BCR to antigen specificity through sequencing (LIBRA-seq), we identified a distinct activated memory B cell subgroup (CD11c CD95) had a higher proportion of SARS-CoV-2 antigen-labeled cells compared with memory B cells. Our results revealed the diversity of paired BCR repertoire and the non-stochastic pairing of SARS-CoV-2 antigen-specific immunoglobulin heavy and light chains after SARS-CoV-2 infection. The public antibody clonotypes were shared by distinct convalescent individuals. Moreover, several antibodies isolated by LIBRA-seq showed high binding affinity against SARS-CoV-2 receptor-binding domain (RBD) or nucleoprotein (NP) via ELISA assay. Two RBD-reactive antibodies C14646P3S and C2767P3S isolated by LIBRA-seq exhibited high neutralizing activities against both pseudotyped and authentic SARS-CoV-2 viruses in vitro. Our study provides fundamental insights into B cell response following SARS-CoV-2 infection at the single-cell level.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41392-021-00610-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8127497PMC
May 2021

Network analysis indicating the pharmacological mechanism of Yunpi-Qufeng-Chushi-prescription in prophylactic treatment of rheumatoid arthritis.

BMC Complement Med Ther 2021 May 15;21(1):142. Epub 2021 May 15.

School of Basic Medical Sciences, Zhejiang Chinese Medical University, 548 Binwen Road, Hangzhou, 310000, Zhejiang, China.

Background: Rheumatoid arthritis (RA), is an autoimmune inflammatory disease with increasing global morbidity and high disability. Early treatment is an effective intervention to slow down joint deformation. However, as for early RA and pre-RA patients, it sometimes takes a long time to make a definite diagnosis and few guidelines have made suggestion for these suspected or early phrase individuals. Yunpi-Qufeng-Chushi-Prescription (YQCP) is an optimization of the traditional formula, Cangzhu Fangfeng Tang which is effective for arthromyodynia management.

Methods: In this study, LC-MS identify the main component of YQCP. Ingredients of the 11 herbs were collected from Traditional Chinese Medicine Integrated Database (TCMID). Targets of these ingredients were collected from two source, TCMID and PharmMapper. Microarray of 20 early untreated RA patients and corresponding health control were download from NCBI Gene Expression Omnibus (GEO) database to defined the differential expressed genes. Gene ontology analysis and KEGG enrichment analysis were carried out for the YQCP. Protein-protein interactions (PPIs) networks were constructed to identify the hub targets. At last, molecular docking (MD) were conducted to further verified the the possibility of YQCP for RA therapy.

Result: The study indicated that by acting on hub targets such as C3, EGFR, SRC and MMP9, YQCP may influence the mature of B cells and inhibit B cell-related IgG production, regulate oxidative stress and modulate activity of several enzymes including peroxidase and metallopeptidase to delay the occurrence and progress of RA and benefit the pre-RA or early RA patients.

Conclusion: YQCP is a potential effective therapy for prophylactic treatment of RA.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s12906-021-03311-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8122573PMC
May 2021

When to perform curettage after uterine artery embolization for cesarean scar pregnancy: a clinical study.

BMC Pregnancy Childbirth 2021 May 10;21(1):367. Epub 2021 May 10.

Department of Gynecology and Obstetrics, Development and Related Diseases of Women and Children Key Laboratory of Sichuan Province, Key Laboratory of Birth Defects and Related Diseases of Women and Children, Ministry of Education, West China Second Hospital, Sichuan University, Chengdu, Sichuan, 610041, People's Republic of China.

Background: Prophylactic uterine artery embolization (UAE) combined with subsequent curettage is suggested as an effective and minimally invasive treatment strategy for cesarean scar pregnancy (CSP) with a high bleeding risk. However, the timing of curettage after UAE remains to be studied. Thus, we aimed to identify the optimal time interval to perform curettage after UAE in patients with CSP.

Methods: We conducted a retrospective cohort study in a large medical center for women and children in Southwest China. CSP patients treated by UAE combined with subsequent curettage were included and grouped by the treatment time interval between these two procedures. The clinical outcomes among arms were compared by univariate and multivariable analysis.

Results: Our study included 314 CSP patients who received this combination treatment in our department from January 2014 to December 2019. The median time interval between UAE and curettage was 48 h, with a range of 12-168 h among all participants. Thirty-two patients (10.2%) experienced intraoperative hemorrhage (blood loss ≥200 mL). Intrauterine balloon tamponade was used in 17 cases (5.4%). In 14 cases (4.5%), the procedure was converted to laparoscopy (or laparotomy). In the cohort study, patients with longer treatment intervals had more intraoperative blood loss and a higher incidence of complications than those with shorter intervals (P < 0.05). The rates of intraoperative bleeding were 5.0% for patients who received curettage within 24 h after UAE (Arm 1) and 19.4% for those who had a treatment interval longer than 72 h (Arm 4). In the multivariable logistic regression model of bleeding, a treatment interval > 72 h had an adjusted odds ratio of 3.37 (95% confidence interval: 1.40-8.09).

Conclusion: We suggest that curettage not be delayed longer than 72 h after UAE in this combined treatment of CSP.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s12884-021-03846-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8108320PMC
May 2021

Viral-Host Interactome Analysis Reveals Chicken STAU2 Interacts With Non-structural Protein 1 and Promotes the Replication of H5N1 Avian Influenza Virus.

Front Immunol 2021 21;12:590679. Epub 2021 Apr 21.

State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China.

As a highly pathogenic influenza virus, H5N1 avian influenza virus (AIV) poses a great threat to poultry production and public health. H5N1 AIV has a small genome and, therefore, relies heavily on its host cellular machinery to replicate. To develop a comprehensive understanding of how H5N1 AIV rewires host cellular machinery during the course of infection, it is crucial to identify which host proteins and complexes come into physical contact with the viral proteins. Here, we utilized affinity purification mass spectrometry (AP-MS) to systematically determine the physical interactions of 11 H5N1 AIV proteins with host proteins in chicken DF1 cells. We identified with high confidence 1,043 H5N1 AIV-chicken interactions involving 621 individual chicken proteins and uncovered a number of host proteins and complexes that were targeted by the viral proteins. Specifically, we revealed that chicken Staufen double-stranded RNA-binding protein 2 interacts with AIV non-structural protein 1 (NS1) and promotes the replication of the virus by enhancing the nuclear export of mRNA. This dataset facilitates a more comprehensive and detailed understanding of how the host machinery is manipulated during the course of H5N1 AIV infection.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fimmu.2021.590679DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8098808PMC
April 2021

Ultrahigh-response hydrogen sensor based on PdO/NiO co-doped InO nanotubes.

J Colloid Interface Sci 2021 Oct 28;599:533-542. Epub 2021 Apr 28.

School of Physical Science and Technology, Lanzhou University, Lanzhou 730000, China. Electronic address:

Hydrogen can be regarded as an ideal type of secondary energy considering its potential for achieving renewable and sustainable development due to water being its sole combustion product and its possible production by solar energy-based water electrolysis. Monitoring the presence and concentration of hydrogen during production, transportation, and application requires a hydrogen gas sensor with high response, high selectivity, and fast response and recovery times. In an attempt to meet these requirements, NiO and PdO are used in the co-doping of InO nanotubes by subsequent electrospinning and impregnation under UV irradiation. The fabricated hydrogen gas sensor demonstrates an ultrahigh response of 487.52, a fast response time of 1 s and high selectivity at an operating temperature of 160 °C, which characteristics are superior to reported monometal-doped hydrogen sensors. The remarkable gas sensing performance could be attributed to the synergistic effect of the resistance modulation, the chemical sensitization of PdO, and the catalytic effect of NiO. This study demonstrates that co-doping of PdO and NiO on InO nanotubes is an effective way to improve hydrogen sensing characteristics more effectively than doping with PdO or NiO alone, and provides a potential application for the fast and accurate detection of hydrogen.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jcis.2021.04.125DOI Listing
October 2021

Structural basis for SARS-CoV-2 neutralizing antibodies with novel binding epitopes.

PLoS Biol 2021 05 7;19(5):e3001209. Epub 2021 May 7.

MOE Key Laboratory of Protein Science & Collaborative Innovation Center of Biotherapy, School of Medicine, Tsinghua University, Beijing, China.

The ongoing Coronavirus Disease 2019 (COVID-19) pandemic caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) threatens global public health and economy unprecedentedly, requiring accelerating development of prophylactic and therapeutic interventions. Molecular understanding of neutralizing antibodies (NAbs) would greatly help advance the development of monoclonal antibody (mAb) therapy, as well as the design of next generation recombinant vaccines. Here, we applied H2L2 transgenic mice encoding the human immunoglobulin variable regions, together with a state-of-the-art antibody discovery platform to immunize and isolate NAbs. From a large panel of isolated antibodies, 25 antibodies showed potent neutralizing activities at sub-nanomolar levels by engaging the spike receptor-binding domain (RBD). Importantly, one human NAb, termed PR1077, from the H2L2 platform and 2 humanized NAb, including PR953 and PR961, were further characterized and subjected for subsequent structural analysis. High-resolution X-ray crystallography structures unveiled novel epitopes on the receptor-binding motif (RBM) for PR1077 and PR953, which directly compete with human angiotensin-converting enzyme 2 (hACE2) for binding, and a novel non-blocking epitope on the neighboring site near RBM for PR961. Moreover, we further tested the antiviral efficiency of PR1077 in the Ad5-hACE2 transduction mouse model of COVID-19. A single injection provided potent protection against SARS-CoV-2 infection in either prophylactic or treatment groups. Taken together, these results shed light on the development of mAb-related therapeutic interventions for COVID-19.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1371/journal.pbio.3001209DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8133496PMC
May 2021

Relationship Between Metabolic Syndrome and Cognitive Function: A Population-Based Study of Middle-Aged and Elderly Adults in Rural China.

Diabetes Metab Syndr Obes 2021 30;14:1927-1935. Epub 2021 Apr 30.

Department of Neurology, The Second People's Hospital of Wuhu, Wuhu, Anhui, People's Republic of China.

Introduction: To explore the relationship between metabolic syndrome (MetS) and cognitive impairment in a low-income and low-education population.

Methods: All residents aged ≥45 years in a low-income population in Tianjin, China, were eligible to participate in this study. The Mini-Mental State Examination (MMSE) scale was used to conduct a preliminary screening and assessment of the participants' cognitive statuses. The MMSE components are orientation, registration, attention and calculation, recall, and language.

Results: In this population, the prevalences of MetS and cognitive impairment were 54.1% and 44.5%, respectively. In the overall population, the registration score was 0.105 points lower in the elevated triglycerides (TG) group than in the normal TG group (β, -0.105; 95% confidence interval [CI]: -0.201, -0.010; P=0.030). In men, high TG was associated with registration scores that were 0.152 points lower than those in the normal TG group (95% CI: -0.281, -0.022; P=0.022), while larger WC and lower HDL-C had positive effects on cognitive scores (all P<0.05). However, in women, there were no significant differences between cognitive scores and MetS or its components.

Conclusion: In this population, first, TG had a great impact on cognition, even greater than the impact of MetS on cognition. Second, the impact of MetS components on cognition was more obvious in men, and not all of the effects were negative. Therefore, the effect of MetS on cognition may need to be analyzed separately for different populations, and it may be that the effect of a single component is greater than the overall effect. When formulating prevention strategies for cognitive impairments, population differences must also be taken into consideration.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2147/DMSO.S308250DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8096414PMC
April 2021

A 1T2C FeCAP-Based In-Situ Bitwise X(N)OR Logic Operation with Two-Step Write-Back Circuit for Accelerating Compute-In-Memory.

Micromachines (Basel) 2021 Apr 1;12(4). Epub 2021 Apr 1.

Institute of Microelectronics of Chinese Academy of Sciences, Beijing 100029, China.

Ferroelectric capacitors (FeCAPs) with high process compatibility, high reliability, ultra-low programming current and fast operation speed are promising candidates to traditional volatile and nonvolatile memory. In addition, they have great potential in the fields of storage, computing, and memory logic. Nevertheless, effective methods to realize logic and memory in FeCAP devices are still lacking. This study proposes a 1T2C FeCAP-based in situ bitwise X(N)OR logic based on a charge-sharing function. First, using the 1T2C structure and a two-step write-back circuit, the nondestructive reading is realized with less complexity than the previous work. Second, a method of two-line activation is used during the operation of X(N)OR. The verification results show that the speed, area and power consumption of the proposed 1T2C FeCAP-based bitwise logic operations are significantly improved.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/mi12040385DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8065609PMC
April 2021

Bioavailability Evaluation of Perchlorate in Different Foods : Comparison with Assays and Implications for Human Health Risk Assessment.

J Agric Food Chem 2021 May 21;69(17):5189-5197. Epub 2021 Apr 21.

Key Laboratory for Deep Processing of Major Grain and Oil (The Chinese Ministry of Education), College of Food Science and Engineering, Wuhan Polytechnic University, Wuhan 430023, Hubei, People's Republic of China.

Perchlorate in various foods continuously arouses public health concern. Bioavailability is a critical parameter to better estimate perchlorate exposure from diets. In this study, perchlorate bioavailability in five foods was determined in an mouse model and compared with bioaccessibility/bioavailability. The estimated perchlorate bioavailability for different foods ranged from 18.01 ± 4.53% to 45.60 ± 7.11%, with the order lettuce > pork > rice > milk powder > soybean. Moisture, fiber, and fat in foods were identified as critical factors affecting perchlorate bioavailability (correlation = 0.71, 0.52, and -0.67, respectively). Linear regression analysis revealed that the perchlorate bioavailability determined using the Caco-2 cell model has the potential to estimate the perchlorate bioavailability in foods ( = 0.67, slope = 1.33, and intercept = 4.99). These findings provide insights into the effects of the food matrices on perchlorate bioavailability and could contribute to decrease the uncertainty regarding perchlorate dietary exposure risk assessment.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.jafc.1c00539DOI Listing
May 2021

High-Frequency Ultrasound for Evaluation of the Pathological Invasion Level of Extramammary Paget Disease.

J Ultrasound Med 2021 Apr 15. Epub 2021 Apr 15.

Department of Medical Ultrasound, Shanghai Skin Disease Hospital, Ultrasound Research and Education Institute, Tongji University School of Medicine, Shanghai, China.

Objectives: Pathological invasion level of extramammary Paget disease (EMPD) is strongly related with its risk staging, treatment, and prognosis. However, the current evaluation before treatments fails to evaluate pathological invasion level of EMPD. High-frequency ultrasound (HFUS) may play a key role to solve this problem. The purpose was to explore the performance of HFUS in the evaluation of pathological invasion level of EMPD.

Methods: Sixty pathologically proven EMPD patients were retrospectively enrolled and divided into 2 groups as follows: in situ in the epidermis (IE) (n = 42) and invasion into the dermis or subcutaneous (ID) (n = 18) groups. Clinical and HFUS features were compared between the 2 groups.

Results: Between the 2 groups, HFUS features (lesion shape, internal echogenicity and echotexture, surface shape, epidermal hyperechoic layer on the surface, the "pseudopod sign", and color Doppler ultrasound features) and clinical features were comparable (all P >.05). Tumor growth pattern significantly differed between the 2 groups (P <.05). Infiltration depth was significantly deeper for the ID group than the IE group (P <.05). With a cutoff value of 1.55 mm for infiltration depth, the area under the receiver operating characteristic curve was 0.833.

Conclusions: HFUS features of tumor growth pattern and infiltration depth may contribute to the assessment of invasion level of EMPD.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/jum.15716DOI Listing
April 2021

Surface plasmon resonances boost the transverse magneto-optical Kerr effect in a CoFeB slab covered by a subwavelength gold grating for highly sensitive detectors.

Opt Express 2021 Mar;29(7):10546-10555

Herein, we have theoretically investigated the sensing performance-including enormous increase in the sensitivity and figure of merit (FOM)-of a magneto-optical surface plasmon resonance (MOSPR) sensor, which is based on the transverse magneto-optical Kerr effect (T-MOKE) in a ferromagnet coupled with a noble-metal grating. Specifically, we propose to use a CoFeB magnetic slab covered by a subwavelength, periodic gold grating configured as a magnetoplasmonic heterostructure. In such a device, sharp, Fano-like T-MOKE signals of high amplitude can be achieved due to the surface plasmon resonances (SPRs) excited in the presence of the gold grating, especially after optimizing the grating period. Tiny changes in the refractive index of an analyte surrounding the MOSPR sensor can be measured by analyzing the shift in the angle of incidence of the resonance positions of the T-MOKE signals. By calculating these resonance positions, we have demonstrated that it is possible to achieve a considerable sensitivity of 105° RIU and a FOM as high as ∼10. Such a MOSPR sensing system can be exploited in biosensors with high detection limits.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.414749DOI Listing
March 2021

Microbial mechanism of enhancing methane production from anaerobic digestion of food waste via phase separation and pH control.

J Environ Manage 2021 Jun 26;288:112460. Epub 2021 Mar 26.

Shenzhen Engineering Research Laboratory for Sludge and Food Waste Treatment and Resource Recovery, Graduate School at Shenzhen, Tsinghua University, Shenzhen, 518055, China.

Phase separation and pH control are commonly used to improve methane production during anaerobic digestion (AD) of food waste, but their influencing mechanisms have not been fully discovered through microbial analysis. In this study, single-phase AD (SPAD), two-phase AD without pH control (TPAD-pHUC), and TPAD with fermentation pH controlled at 6.0 and 4.5 were conducted. The results showed that phase separation decreased the ratio of total bacteria to total archaea in the methanogenic phase. At the organic loading rate (OLR) of 1.9 g/(L·d), methanogenesis was dominated by acetoclastic Methanosaeta in both SPAD and TPAD-pHUC, while elevated Methanoculleus and active hydrogen production initiated a shift from the acetoclastic to hydrogenotrophic pathway in SPAD as OLR increased, eventually resulting in excessive acidification at OLR 3.2 g/(L·d). TPAD-pHUC was dominated by Methanosaeta with scarce hydrogen production genes, and thus maintained a delicate balance between fewer acidogens and methanogens at OLR 3.2-3.7 g/(L·d). TPAD with pH control exhibited higher methane yield (460-482 ml/g) at OLR 1.9 g/(L·d) due to the enhancement of protein degradation and the conversion from methylated compounds to methane by Methanosarcina. High Na concentration facilitated the proliferation of hydrogen production bacteria, but inhibited acetoclastic methanogenesis at OLR 2.4 g/(L·d). In comparison with SPAD and pH control, TPAD without pH control, integrating 4 d acidogenesis and 22 d methanogenesis, exhibited the best and steady performance at OLR 3.7 g/(L·d) with methane production exceeding 370 ml/g.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jenvman.2021.112460DOI Listing
June 2021

Effect of honeycomb, granular, and powder activated carbon additives on continuous lactic acid fermentation of complex food waste with mixed inoculation.

J Biosci Bioeng 2021 Jun 26;131(6):655-662. Epub 2021 Mar 26.

Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China.

To accelerate and stabilize lactic acid fermentation from food waste, three types of activated carbon, including honeycomb activated carbon, granular activated carbon, and powder activated carbon, were tested as additives in continuous food waste fermentation processes. The results showed that carbohydrate was the primary substrate for lactic acid production, but its conversion reached a high, stable level after a long period of microbial acclimation in the control system. Activated carbon, especially honeycomb activated carbon accelerated the stabilization of lactic acid fermentation and enhanced the tolerance of fermentation systems to a hostile and fluctuating environment. The addition of activated carbon increased the oxidation-reduction potential to approximately 100 mV and altered the microbial communities. Homolactic fermentation bacteria were dominant in all the systems, and the honeycomb activated carbon addition stimulated the growth of unclassified Lactobacillus and immobilized Lactobacillus panis with strong carbohydrate metabolism. In addition, powder activated carbon enhanced the degradation of protein due to the multiplying Pseudomonas. At the stable stage, the organic conversion rates were close in the control system and the systems with the activated carbon addition, and the lactic acid concentrations in these systems remained at 8000-10,000 mg/L. Considering the cost of the additives, honeycomb activated carbon is a good choice to stabilize lactic acid production from food waste.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jbiosc.2021.02.009DOI Listing
June 2021

High-frequency ultrasound in the diagnosis of the spectrum of cutaneous squamous cell carcinoma: Noninvasively distinguishing actinic keratosis, Bowen's Disease, and invasive squamous cell carcinoma.

Skin Res Technol 2021 Mar 10. Epub 2021 Mar 10.

Department of Medical Ultrasound, Shanghai Skin Disease Hospital, Ultrasound Research and Education Institute, Tongji University School of Medicine, Shanghai, China.

Objective: To evaluate high-frequency ultrasound (HFUS) features for diagnosing cutaneous squamous cell carcinoma (cSCC) as a spectrum of progressively advanced malignancies, including precursor actinic keratosis (AK), Bowen's disease (BD), and invasive squamous cell carcinoma (iSCC).

Method: In this retrospective study, 160 skin lesions diagnosed histopathologically (54 AK, 54 BD, and 52 iSCC) in 160 patients were included. The HFUS features of AK, BD, and iSCC were analyzed. The obtained data were evaluated using univariate and forward multivariate logistic regression analyses.

Results: The most significant HFUS features in AK were regular surface (odds ratio [OR], 8.42) and irregular basal border (OR, 6.36). The most significant HFUS features in BD were crumpled surface (OR, 19.62) and layer involvement confined to the epidermis (OR, 3.96). The most significant HFUS features in iSCC were concave surface (OR, 27.06), stratum corneum (SC) detachment (OR, 14.41), irregular basal border (OR, 4.01), and convex surface (OR, 3.73). The characteristics of surface features, basal border, and layer involvement could be valuable HFUS clues in the discrimination of AK, BD, and iSCC.

Conclusion: High-frequency ultrasound is valuable for the differentiation of AK, BD, and iSCC, which may allow dynamic and noninvasive monitoring in the spectrum of cSCC.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/srt.13028DOI Listing
March 2021

Impaired pain empathic abilities among patients with functional dyspepsia.

Cogn Neuropsychiatry 2021 05 17;26(3):153-165. Epub 2021 Mar 17.

Department of Neurology, the First Affiliated Hospital of Anhui Medical University, Hefei, People's Republic of China.

Introduction: Brain structure or functioning abnormality in regions such as insula and anterior cingulate cortex (ACC) is associated with functional dyspepsia (FD) and pain empathy, but the relationship between FD and pain empathy remains unclear. The aim of this study was to compare the pain empathic abilities of FD patients and healthy controls (HCs) and investigate the association of pain empathy with clinical characteristics and quality of life of FD patients.

Methods: Pain empathic abilities was measured in 30 FD patients and 30 HCs using a validated pain empathy paradigm. Demographic characteristics, Helicobacter pylori status, duration, dyspeptic symptom score and Nepean Dyspepsia Life Quality Index (NDLQI) were obtained from all patients.

Results: FD patients scored higher than HCs when rating painful pictures, but the accuracy for painful pictures was significantly lower than HCs. Pearson correlation analysis showed significant negative correlation between NDLQI and pain rating scores for painful pictures. When sex, age, educational level, the number of complaints, duration, infection and NDLQI were included in multiple linear regression analysis, NDLQI was independently associated with pain ratings.

Conclusions: FD patients showed abnormally enhanced pain empathic abilities, which may be associated with the severity of symptoms and quality of life.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/13546805.2021.1897558DOI Listing
May 2021

Bidirectional band-switchable nano-film absorber from narrowband to broadband.

Opt Express 2021 Feb;29(4):5110-5120

We propose a switchable perfect absorber with broadband and narrowband absorption based on alternating dielectric and metal nano-film structures in this paper. The lithography-free pattern is equipped with polarization insensitivity, good ductility and manufacturability, which has great significance in practical device development and applications. The quasi-complete selective absorption of incident light can be originated from asymmetric Fabry-Perot resonance, which combines the destructive interference in dielectric layers with inherent absorption in metal layers. When the light incidents on the surface covered with ultra-thin metal film of this structure, it acts as a narrowband absorber with over 99.90% absorption at 771 nm wavelength and a full wave at half maximum of 20 nm. When the light incidents on other surfaces covered with anti-reflective dielectric film, it achieves broadband perfect absorption with an average absorption exceeding 96.02% in a 500-1450 nm wavelength range. The absorption spectrum of oblique incidence shows that the broadband absorption behaves big angle range tolerance while the narrowband absorption exhibits angular dependence. The band-switchable performance of this absorber makes it valuable for energy harvesting/re-radiation applications in solar thermal photovoltaic systems.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.417780DOI Listing
February 2021

Hepatic Knockdown of Endothelin Type A Receptor (ETAR) Ameliorates Hepatic Insulin Resistance and Hyperglycemia Through Suppressing p66Shc-Mediated Mitochondrial Fragmentation in High-Fat Diet-Fed Mice.

Diabetes Metab Syndr Obes 2021 2;14:963-981. Epub 2021 Mar 2.

School of Life Science, Jiangsu Normal University, Xuzhou, Jiangsu, 221116, People's Republic of China.

Background: Emerging evidence from animal studies and clinical trials indicates that systemic inhibition of endothelin1 (ET1) signaling by endothelin receptor antagonists improves pathological features of diabetes and its complications. It is indicated that endothelin type A receptor (ETAR) plays a major role in ET1-mediated pathophysiological actions including diabetic pathology. However, the effects as well as the mechanistic targets of hepatic ET1/ETAR signaling inhibition on the pathology of metabolic diseases remain unclear. This study aimed to investigate the beneficial effects as well as the underlying mechanisms of hepatic ETAR knockdown on metabolism abnormalities in high-fat diet (HFD)-fed mice.

Methods: Mice were fed a HFD to induce insulin resistance and metabolism abnormalities. L02 cells were treated with ET1 to assess the action of ET1/ETAR signaling in vitro. Liver-selective knockdown of ETAR was achieved by tail vein injection of adeno-associated virus 8 (AAV8). Systemic and peripheral metabolism abnormalities were determined in vivo and in vitro. Mitochondrial fragmentation was observed by transmission electron microscope (TEM) and mitoTracker red staining.

Results: Here we provided in vivo and in vitro evidence to demonstrate that liver-selective knockdown of ETAR effectively ameliorated hepatic insulin resistance and hyperglycemia in HFD-fed mice. Mechanistically, hepatic ETAR knockdown alleviated mitochondrial fragmentation and dysfunction via inactivating 66-kDa Src homology 2 domain-containing protein (p66Shc) to recover mitochondrial dynamics, which was mediated by inhibiting protein kinase Cδ (PKCδ), in the livers of HFD-fed mice. Ultimately, hepatic ETAR knockdown attenuated mitochondria-derived oxidative stress and related liver injuries in HFD-fed mice. These ETAR knockdown-mediated actions were confirmed in ET1-treated L02 cells.

Conclusion: This study defined an ameliorative role of hepatic ETAR knockdown in HFD-induced metabolism abnormalities by alleviating p66Shc-mediated mitochondrial fragmentation and consequent oxidative stress-related disorders and indicated that hepatic ETAR knockdown may be a promising therapeutic strategy for metabolic diseases.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2147/DMSO.S299570DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7936928PMC
March 2021

Deciphering potential pharmacological mechanism of Sha-Shen-Mai-Dong decoction on primary Sjogren's syndrome.

BMC Complement Med Ther 2021 Mar 1;21(1):79. Epub 2021 Mar 1.

College of Basic Medical Sciences, Zhejiang Chinese Medical University, Hangzhou, 310058, China.

Background: Sha-Shen-Mai-Dong decoction (SSMD) is a classical prescription widely used in primary Sjogren's Syndrome (pSS) therapy. This study aims to explore the potential pharmacological mechanism of SSMD on pSS.

Methods: Active components of SSMD were obtained from Traditional Chinese Medicine Integrative Database and Traditional Chinese Medicine Systems Pharmacology databases and targets of SSMD were predicted by Pharmmapper and STITCH database. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were carried out to explore the function characteristics of SSMD. The expression matrix of microarray of pSS was obtained from Gene Expression Omnibus and we obtained 162 differentially expressed genes (DEGs). Protein-protein interaction (PPI) networks were constructed to identify the hub targets. Principal component analysis (PCA) and molecular docking were conducted to further elucidate the possibility of SSMD for pSS.

Results: SSMD contained a total of 1056 active components, corresponding to 88 targets, among which peripheral myelin protein 2(PMP2), androgen receptor (AR) and glutamic acid decarboxylase 1(GAD1) are associated with multiple active components in SSMD and may be the core targets. Moreover, these targets were closely related to tissue pathological injury in SS, such as lacrimal gland, salivary gland and nervous system injury. GO and KEGG analysis showed that 88 targets enriched in REDOX process, transcriptional regulation and negative regulation of apoptosis process. Besides, SSMD may influence the cell proliferation, gene transcription through regulating Ras and cAMP-related signaling pathways. In addition, SSMD may show effects on immune regulation, such as macrophage differentiation, Toll-like receptor 4 signaling pathway and T-helper 1 in SS. Moreover, PPI network suggested that FN1, MMP-9 may be the hub targets in SSMD. Result of PCA and molecular docking analysis further determined the feasibility of SSMD in treating pSS.

Conclusion: SSMD can regulate multiple biological processes by virtue of its multiple active components, thus showing prominent advantage in the treatment of pSS. The discovery of active ingredients and targets in SSMD provides valuable resources for drug research and development for pSS.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s12906-021-03257-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7923330PMC
March 2021

Distinct mechanisms for TMPRSS2 expression explain organ-specific inhibition of SARS-CoV-2 infection by enzalutamide.

Nat Commun 2021 02 8;12(1):866. Epub 2021 Feb 8.

State Key Laboratory of Cell Biology, Shanghai Key Laboratory of Molecular Andrology, Shanghai Institute of Biochemistry and Cell Biology, CAS Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, 200031, China.

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has rapidly become a global public health threat. The efficacy of several repurposed drugs has been evaluated in clinical trials. Among these drugs, a second-generation antiandrogen agent, enzalutamide, was proposed because it reduces the expression of transmembrane serine protease 2 (TMPRSS2), a key component mediating SARS-CoV-2-driven entry, in prostate cancer cells. However, definitive evidence for the therapeutic efficacy of enzalutamide in COVID-19 is lacking. Here, we evaluated the antiviral efficacy of enzalutamide in prostate cancer cells, lung cancer cells, human lung organoids and Ad-ACE2-transduced mice. Tmprss2 knockout significantly inhibited SARS-CoV-2 infection in vivo. Enzalutamide effectively inhibited SARS-CoV-2 infection in human prostate cells, however, such antiviral efficacy was lacking in human lung cells and organoids. Accordingly, enzalutamide showed no antiviral activity due to the AR-independent TMPRSS2 expression in mouse and human lung epithelial cells. Moreover, we observed distinct AR binding patterns between prostate cells and lung cells and a lack of direct binding of AR to TMPRSS2 regulatory locus in human lung cells. Thus, our findings do not support the postulated protective role of enzalutamide in treating COVID-19 through reducing TMPRSS2 expression in lung cells.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41467-021-21171-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7870838PMC
February 2021

Intravenous Infusion of Lidocaine Can Accelerate Postoperative Early Recovery in Patients Undergoing Surgery for Obstructive Sleep Apnea.

Med Sci Monit 2021 Feb 2;27:e926990. Epub 2021 Feb 2.

Department of Ear, Nose and Throat, The Affiliated Huaian Hospital of Xuzhou Medical University and Huaian Second People's Hospital, Huaian, Jiangsu, China (mainland).

Obstructive sleep apnea (OSA) is defined by intermittent and recurrent episodes of partial or complete obstruction of the upper airway during sleep. Intermittent and recurrent hypoxia/reoxygenation is the main pathophysiological mechanism of OSA. Its consequences include systemic inflammation, activation of the sympathetic nervous system, and release of oxygen free radicals. Infusion of intravenous (IV) lidocaine has anti-inflammatory, antihyperalgesic, and analgesic properties, supporting its use as an anesthetic adjuvant. Lidocaine can reduce nociception and/or cardiovascular responses to surgical stress, as well as postoperative pain and/or analgesic requirements. Because of the high prevalence of OSA in obese patients, the use of opioids to manage postoperative pain in that population is often accompanied by the development of adverse respiratory events, such as hypoventilation and hypoxemia. IV infusion of lidocaine has been shown to enhance the quality of early recovery after laparoscopic bariatric and upper airway surgery. However, limited evidence exists regarding its use in patients undergoing surgery for OSA. In addition, whether IV infusion of lidocaine can improve postoperative early recovery in patients undergoing surgery for OSA remains unknown. Therefore, we hypothesized that IV infusion of lidocaine can improve postoperative early recovery in patients undergoing surgery for OSA. Perioperative infusion also may be a promising analgesic adjunct to enhanced recovery after surgery (ERAS) protocols.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.12659/MSM.926990DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7870156PMC
February 2021

Printable and Recyclable Conductive Ink Based on a Liquid Metal with Excellent Surface Wettability for Flexible Electronics.

ACS Appl Mater Interfaces 2021 Feb 2;13(6):7443-7452. Epub 2021 Feb 2.

Joint Key Laboratory of the Ministry of Education, Institute of Applied Physics and Materials Engineering, University of Macau, Avenida da Universidade, Taipa 999078, Macau SAR, China.

Flexible electronics greatly facilitate human life due to their convenience and comfortable utilization. Liquid metals are an ideal candidate for flexible devices; however, the high surface tension and poor surface wettability restrict their application on diverse substrates. Herein, a printable and recyclable ink composed of poly(vinyl alcohol) and a liquid metal (PVA-LM) was developed to resolve these problems. The materials were designed considering the compatibility between PVA and the liquid metal, and the composite theory was applied to determine the component proportion. The developed composites improved the surface wettability of the liquid metal on diverse substrates, and three-dimensional (3D) printing technology was chosen to maximize the use of this material. Moreover, the PVA-LM ink showed excellent conductivity of about 1.3 × 10 S/m after being turned on, which favored the designing of alarm systems and object locators. The flexible sensors produced with this ink have broad application, high sensitivity, and superstable signal generation even after 200 cycles. When acting as strain sensors, the constructed composites had high sensitivity for monitoring the human movements. Furthermore, liquid metals in printed products can be recycled under alkaline conditions. This study opens a new direction for the next generation of environmentally friendly flexible devices.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acsami.0c20549DOI Listing
February 2021

Ex-situ XPS analysis of yolk-shell SbO/WO for ultra-fast acetone resistive sensor.

J Hazard Mater 2021 06 23;412:125175. Epub 2021 Jan 23.

School of Physical Science and Technology, Lanzhou University, Lanzhou 730000, PR China. Electronic address:

The preparation of fast, highly responsive and reliable gas sensing devices for the detection of acetone gas is considered to be a key challenge for the development of accurate disease diagnosis systems through exhaled respiratory gases. In the paper, yolk shell SbO/WO is synthesized and its gas sensing performance was studied by static test system. Special, the maximum response value of 1:1 SbO/WO yolk-shell (WO-1 YSL) sensor to 100 ppm acetone can reach as high as 50.0 at 200 ℃. And it also exhibits excellent response/recover time (4 s/5 s), low detection limit (2 ppm) and superior selectivity towards acetone. More importantly, in mixed selective gas test, the sensor shows high selectivity towards acetone. And the mechanism is analyzed by ex-situ XPS. The excellent gas-sensing performance can be attributed to unique yolk-shell structure, which facilitates the rapid transport of charge carriers from the surface to the bulk and provides more active sites for gas adsorption and desorption; the heterojunction between of SbO and WO, which promotes oxygen pre-adsorption on the surface and increasing the interfacial potential; the increased oxygen vacancies which allowing more chemisorbed oxygen to form.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jhazmat.2021.125175DOI Listing
June 2021

Predictive Hydration Model of Portland Cement and Its Main Minerals Based on Dissolution Theory and Water Diffusion Theory.

Materials (Basel) 2021 Jan 27;14(3). Epub 2021 Jan 27.

State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan 430072, China.

Efficient and accurate cement hydration simulation is an important issue for predicting and analyzing concrete's performance evolution. A large number of models have been proposed to describe cement hydration. Some models can simulate the test results with high accuracy by constructing reasonable functions, but they are based on mathematical regression and lack of physical background and prediction ability. Other models, such as the famous HYMOSTRUC model and CEMHYD3D model, can predict the hydration rate and microstructure evolution of cement based on its initial microstructure. However, this kind of prediction model also has some limitations, such as the inability to fully consider the properties of cement slurry, or being too complicated for use in finite element analysis (FEA). In this study, the hydration mechanisms of the main minerals in Portland cement (PC) are expounded, and the corresponding hydration model is built. Firstly, a modified particle hydration model of tricalcium silicate (CS) and alite is proposed based on the moisture diffusion theory and the calcium silicate hydrate (C-S-H) barrier layer hypothesis, which can predict the hydration degree of CS and alite throughout the age. Taking the hydration model of CS as a reference, the hydration model of dicalcium silicate (CS) is established, and the synergistic hydration effect of CS and CS is calibrated by analyzing the published test results. The hydration model of tricalcium aluminate(CA)-gypsum system is then designed by combining the theory of dissolution and diffusion. This model can reflect the hydration characteristics of CA in different stages, and quantify the response of the hydration process of CA to different gypsum content, water-cement ratio, and particle size distribution. Finally, several correction coefficients are introduced into the hydration model of the main mineral, to consider the synergistic hydration effect among the minerals to some extent and realize the prediction of the hydration of PC.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/ma14030595DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7865312PMC
January 2021

Enhancement versus neutralization by SARS-CoV-2 antibodies from a convalescent donor associates with distinct epitopes on the RBD.

Cell Rep 2021 02 12;34(5):108699. Epub 2021 Jan 12.

Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences, Biosafety Level 3 Laboratory, Shanghai Medical College, Fudan University, Shanghai 200032, China. Electronic address:

Several potent neutralizing antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus have been identified. However, antibody-dependent enhancement (ADE) has not been comprehensively studied for SARS-CoV-2, and the relationship between enhancing versus neutralizing activities and antibody epitopes remains unknown. Here, we select a convalescent individual with potent IgG neutralizing activity and characterize his antibody response. Monoclonal antibodies isolated from memory B cells target four groups of five non-overlapping receptor-binding domain (RBD) epitopes. Antibodies to one group of these RBD epitopes mediate ADE of entry in Raji cells via an Fcγ receptor-dependent mechanism. In contrast, antibodies targeting two other distinct epitope groups neutralize SARS-CoV-2 without ADE, while antibodies against the fourth epitope group are poorly neutralizing. One antibody, XG014, potently cross-neutralizes SARS-CoV-2 variants, as well as SARS-CoV-1, with respective IC (50% inhibitory concentration) values as low as 5.1 and 23.7 ng/mL, while not exhibiting ADE. Therefore, neutralization and ADE of human SARS-CoV-2 antibodies correlate with non-overlapping RBD epitopes.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.celrep.2021.108699DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7802522PMC
February 2021

Microfluidics for the rapid detection of Escherichia coli O157:H7 using antibody-coated microspheres.

Bioengineered 2021 Dec;12(1):392-401

Pathology College, Qiqihar Medical University , Qiqihar, China.

This study developed a novel method for the rapid detection of () O157:H7 on a microfluidic platform. First, the concentration of bacteria in a sample was determined with the adenosine triphosphate (ATP) method. Then, the specific detection of was achieved in a microfluidic chip by the immune-microsphere technique. The influences of the culture time, flow rate and capture time on the detection of the target bacteria were investigated systematically. Generally, with increasing capture time, more bacteria could be captured by the microspheres, which had a positive effect on bacterial detection. Furthermore, the sensitivity and specificity of the method were also tested. The results showed that this method could specifically detect with a sensitivity as high as 49.1 cfu/μL; the consumption of bacteria was 1 μL, and the reagent was at the microliter level. The testing time can be controlled within one and a half hours, and the cost of testing was approximately RMB 10. The method described in this article is simple and accurate and has great application value in bacterial detection for medical diagnostics.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/21655979.2020.1870805DOI Listing
December 2021