Publications by authors named "Cun Li"

141 Publications

Robust SARS-CoV-2 infection in nasal turbinates after treatment with systemic neutralizing antibodies.

Cell Host Microbe 2021 Feb 25. Epub 2021 Feb 25.

AIDS Institute, Li Ka Shing Faculty of Medicine, the University of Hong Kong, Pokfulam, Hong Kong SAR, PRC; State Key Laboratory of Emerging Infectious Diseases, the University of Hong Kong, Pokfulam, Hong Kong SAR, PRC; Department of Microbiology, Li Ka Shing Faculty of Medicine, the University of Hong Kong, Pokfulam, Hong Kong SAR, PRC; Department of Clinical Microbiology and Infection Control, the University of Hong Kong-Shenzhen Hospital, Shenzhen, Guangdong, PRC. Electronic address:

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is characterized by a burst in the upper respiratory portal for high transmissibility. To determine human neutralizing antibodies (HuNAbs) for entry protection, we tested three potent HuNAbs (IC range, 0.0007-0.35 μg/mL) against live SARS-CoV-2 infection in the golden Syrian hamster model. These HuNAbs inhibit SARS-CoV-2 infection by competing with human angiotensin converting enzyme-2 for binding to the viral receptor binding domain (RBD). Prophylactic intraperitoneal or intranasal injection of individual HuNAb or DNA vaccination significantly reduces infection in the lungs but not in the nasal turbinates of hamsters intranasally challenged with SARS-CoV-2. Although postchallenge HuNAb therapy suppresses viral loads and lung damage, robust infection is observed in nasal turbinates treated within 1-3 days. Our findings demonstrate that systemic HuNAb suppresses SARS-CoV-2 replication and injury in lungs; however, robust viral infection in nasal turbinate may outcompete the antibody with significant implications to subprotection, reinfection, and vaccine.
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http://dx.doi.org/10.1016/j.chom.2021.02.019DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7904446PMC
February 2021

Research on micro-leverage in monolithic quartz resonant accelerometer.

Rev Sci Instrum 2021 Feb;92(2):025005

State Key Laboratory for Manufacturing Systems Engineering, Xi'an Jiaotong University, Xi'an 710049, China.

In this study, the application of micro-leverage in the monolithically all-quartz resonant accelerometer is proposed. The magnification of the micro-leverage structure used for a large size double-ended tuning fork (DETF) was analyzed. The effect of DETF's dimension both on its own force-frequency sensitivity and micro-leverage's magnification was investigated. Through the study of the relationship between DETF's force-frequency sensitivity and micro-leverage's magnification, the effect of micro-leverage and the DETF system on the sensitivity of the accelerometer was obtained. The problem of big error in theoretical calculation of micro-leverage magnification was solved because the structural arrangement of the output beam was ignored in the derivation process. The correctness of the analysis was verified by theoretical calculation, simulation, and the experiment. The equivalent structures of tension (compression) stiffness and flexural stiffness of the micro-leverage output beam were obtained by analyzing and simplifying the composite structure of the link beam and DETF. By simplifying the mechanical model of micro-leverage, the amplification factor K of micro-leverage is deduced to be 23. Therefore, the theoretical sensitivity of the sensor is 15.6 Hz/g. The experimental results show that the sensitivity of the accelerometer with the micro-leverage is 16.1 Hz/g, which is close to the theoretical analysis results.
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http://dx.doi.org/10.1063/5.0028633DOI Listing
February 2021

Human Intestinal Organoids Recapitulate Enteric Infections of Enterovirus and Coronavirus.

Stem Cell Reports 2021 Feb 12. Epub 2021 Feb 12.

State Key Laboratory of Emerging Infectious Diseases, The University of Hong Kong, Hong Kong, China; Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, 102 Pokfulam Road, Pokfulam, Hong Kong, China. Electronic address:

Enteroviruses, such as EV-A71 and CVA16, mainly infect the human gastrointestinal tract. Human coronaviruses, including SARS-CoV and SARS-CoV-2, have been variably associated with gastrointestinal symptoms. We aimed to optimize the human intestinal organoids and hypothesize that these optimized intestinal organoids can recapitulate enteric infections of enterovirus and coronavirus. We demonstrate that the optimized human intestinal organoids enable better simulation of the native human intestinal epithelium, and that they are significantly more susceptible to EV-A71 than CVA16. Higher replication of EV-A71 than CVA16 in the intestinal organoids triggers a more vigorous cellular response. However, SARS-CoV and SARS-CoV-2 exhibit distinct dynamics of virus-host interaction; more robust propagation of SARS-CoV triggers minimal cellular response, whereas, SARS-CoV-2 exhibits lower replication capacity but elicits a moderate cellular response. Taken together, the disparate profile of the virus-host interaction of enteroviruses and coronaviruses in human intestinal organoids may unravel the cellular basis of the distinct pathogenicity of these viral pathogens.
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http://dx.doi.org/10.1016/j.stemcr.2021.02.009DOI Listing
February 2021

Development of Three-Dimensional Human Intestinal Organoids as a Physiologically Relevant Model for Characterizing the Viral Replication Kinetics and Antiviral Susceptibility of Enteroviruses.

Biomedicines 2021 Jan 18;9(1). Epub 2021 Jan 18.

State Key Laboratory of Emerging Infectious Diseases, Carol Yu Centre for Infection, Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China.

Enteroviruses are important causes of hand, foot, and mouth disease, respiratory infections, and neurological infections in human. A major hurdle for the development of anti-enterovirus agents is the lack of physiologically relevant evaluation platforms that closely correlate with the in vivo state. We established the human small intestinal organoids as a novel platform for characterizing the viral replication kinetics and evaluating candidate antivirals for enteroviruses. The organoids supported productive replication of enterovirus (EV)-A71, coxsackievirus B2, and poliovirus type 3, as evidenced by increasing viral loads, infectious virus titers, and the presence of cytopathic effects. In contrast, EV-D68, which mainly causes respiratory tract infection in humans, did not replicate significantly in the organoids. The differential expression profiles of the receptors for these enteroviruses correlated with their replication kinetics. Using itraconazole as control, we showed that the results of various antiviral assays, including viral load reduction, plaque reduction, and cytopathic effect inhibition assays, were highly reproducible in the organoids. Moreover, itraconazole attenuated virus-induced inflammatory response in the organoids, which helped to explain its antiviral effects and mechanism. Collectively, these data showed that the human small intestinal organoids may serve as a robust platform for investigating the pathogenesis and evaluating antivirals for enteroviruses.
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http://dx.doi.org/10.3390/biomedicines9010088DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7831294PMC
January 2021

Olaquindox-Induced Liver Damage Involved the Crosstalk of Oxidative Stress and p53 In Vivo and In Vitro.

Oxid Med Cell Longev 2020 18;2020:8835207. Epub 2020 Dec 18.

Department of Pharmacology and Toxicology, College of Veterinary Medicine, China Agricultural University, Yuanmingyuan West Road No. 2, Haidian District, Beijing 100193, China.

Olaquindox (OLA), a member of the quinoxaline-N,N-dioxide family, has been widely used as a growth-promoting feed additive and treatment for bacterial infections. The toxicity has been a major concern, and the precise molecular mechanism remains poorly understood. The present study was aimed at investigating the roles of oxidative stress and p53 in OLA-caused liver damage. In a mouse model, OLA administration could markedly cause liver injury as well as the induction of oxidative stress and activation of p53. Antioxidant N-acetylcysteine (NAC) inhibited OLA-induced oxidative stress and p53 activation in vivo. Furthermore, knockout of the p53 gene could significantly inhibit OLA-induced liver damage by inhibiting oxidative stress and the mitochondria apoptotic pathway, compared to the p53 wild-type liver tissue. The cell model in vitro further demonstrated that p53 knockout or knockdown in the HCT116 cell and L02 cell significantly inhibited cell apoptosis and increased cell viability, presented by suppressing ROS production, oxidative stress, and the Nrf2/HO-1 pathway. Moreover, loss of p53 decreased OLA-induced mitochondrial dysfunction and caspase activations, with the evidence of inhibited activation of phosphorylation- (p-) p38 and p-JNK and upregulated cell autophagy via activation of the LC3 and Beclin1 pathway in HCT116 and L02 cells. Taken together, our findings provided a support that p53 primarily played a proapoptotic role in OLA-induced liver damage against oxidative stress and mitochondrial dysfunction, which were largely dependent on suppression of the JNK/p38 pathway and upregulation of the autophagy pathway via activation of LC3 and Beclin1.
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http://dx.doi.org/10.1155/2020/8835207DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7762677PMC
December 2020

Development of V-Shaped Beam on the Shock Resistance and Driving Frequency of Micro Quartz Tuning Forks Resonant Gyroscope.

Micromachines (Basel) 2020 Nov 17;11(11). Epub 2020 Nov 17.

State Key Laboratory for Manufacturing Systems Engineering, Xi'an Jiaotong University, Xi'an 710049, China.

The application of gyroscopes in harsh environments has always been a hot topic. As a high-quality material for manufacturing gyroscopes, quartz crystals need to be designed and optimized to meet the normal operation of gyroscopes in harsh environments. The Micro Electronics Mechanical System(MEMS) quartz tuning forks resonant gyroscope is one of the quartz gyroscopes. The elastic structure (V-shaped beam) between the anchor support point and tuning forks plays a vital role in the MEMS quartz tuning forks resonant gyroscope. This structure determines the natural frequency of the gyroscope, and more importantly, determines the shock resistance of the gyroscope structure. In this article, the MEMS quartz tuning forks gyroscope with different V-shaped beam thicknesses are simulated and analyzed by finite element analysis simulation software. After the modal analysis and shock simulation (the half-cycle sine shock pulse with amplitude of 1500 g (g is the acceleration of gravity) and duration of 2 ms in the six shock directions), the results show that when the beam thickness is 80 μm, the maximum stress is 94.721 MPa, which is less than the failure stress of quartz crystal. The gyroscope's shock resistance is verified through shock testing.
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http://dx.doi.org/10.3390/mi11111012DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7698545PMC
November 2020

The nonhuman primate hypothalamo-pituitary-adrenal axis is an orchestrator of programming-aging interactions: role of nutrition.

Nutr Rev 2020 12;78(Suppl 2):48-61

Instituto Nacional de Ciencias Médicas y Nutrición, Salvador Zubirán.

Developmental programming alters life-course multi-organ function and significantly affects life-course health. Recently, interest has developed in how programming may influence the rate of aging. This review describes interactions of nutrition and programming-aging interactions in hypothalamo-pituitary-adrenal (HPA) development and function from fetal development to old age. A full picture of these interactions requires data on levels of HPA activity relating to the hypothalamic, adrenal cortical, circulating blood, and peripheral cortisol metabolism. Data are provided from studies on our baboon, nonhuman primate model both across the normal life course and in offspring of maternal baboons who were moderately undernourished by a global 30% diet reduction during pregnancy and lactation. Sex differences in offspring outcomes in response to similar challenges are described. The data clearly show programming of increased HPA axis activity by moderate maternal undernutrition. Increased postnatal circulating cortisol concentrations are related to accelerated aging of the brain and cardiovascular systems. Future studies should address peripheral cortisol production and the influence of aging advantage in females. These data support the view that the HPA is an orchestrator of interactions of programming-aging mechanisms.
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http://dx.doi.org/10.1093/nutrit/nuaa018DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7667468PMC
December 2020

Human coronavirus dependency on host heat shock protein 90 reveals an antiviral target.

Emerg Microbes Infect 2020 Dec;9(1):2663-2672

State Key Laboratory of Emerging Infectious Diseases, The University of Hong Kong, Hong Kong, People's Republic of China.

Rapid accumulation of viral proteins in host cells render viruses highly dependent on cellular chaperones including heat shock protein 90 (Hsp90). Three highly pathogenic human coronaviruses, including MERS-CoV, SARS-CoV and SARS-CoV-2, have emerged in the past 2 decades. However, there is no approved antiviral agent against these coronaviruses. We inspected the role of Hsp90 for coronavirus propagation. First, an Hsp90 inhibitor, 17-AAG, significantly suppressed MERS-CoV propagation in cell lines and physiological-relevant human intestinal organoids. Second, siRNA depletion of Hsp90β, but not Hsp90α, significantly restricted MERS-CoV replication and abolished virus spread. Third, Hsp90β interaction with MERS-CoV nucleoprotein (NP) was revealed in a co-immunoprecipitation assay. Hsp90β is required to maintain NP stability. Fourth, 17-AAG substantially inhibited the propagation of SARS-CoV and SARS-CoV-2. Collectively, Hsp90 is a host dependency factor for human coronavirus MERS-CoV, SARS-CoV and SARS-COV-2. Hsp90 inhibitors can be repurposed as a potent and broad-spectrum antiviral against human coronaviruses.
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http://dx.doi.org/10.1080/22221751.2020.1850183DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7751432PMC
December 2020

An integrated packaged resonant accelerometer with temperature compensation.

Rev Sci Instrum 2020 Oct;91(10):105004

State Key Laboratory for Manufacturing System Engineering, Xi'an Jiaotong University, Xi'an 710049, China.

This paper describes the design, fabrication, and testing of an integrated packaged sensor that is composed of a micro resonant accelerometer and a temperature sensor. The resonant accelerometer with differential configuration consists of double quartz resonators and a silicon substrate. When acceleration is applied along the sensing axis, the inertial force induced by the proof mass will transfer force to the resonators, which causes an opposite frequency shift of the dual quartz resonators. The loaded acceleration can be measured through detecting the differential frequency shift. The symmetric differential configuration response to spurious effects of thermal loading and inelastic effect causing prestress in the resonators is similar, which can be reduced by detecting the differential frequency, effectively. However, during the manufacture and packaging process, the otherness of residual stress in two quartz resonators results in that the response of resonators to temperature variation is not strictly the same. In other words, this temperature drift cannot be eliminated by the structure design. Thus, a temperature sensor and an accelerometer were packaged in a shell together. These novel integrated sensors can measure acceleration and temperature simultaneously. With the testing temperature data, a novel temperature compensation that is a combination of the variable coefficient regression and least squares support vector machine is used for improving the performance of the accelerometer. By means of this compensation and field programmable gate array, a real-time and online compensation is achieved. The tumble testing results indicate that the sensitivity of the accelerometer is ∼16.97 Hz/g. With the temperature compensation, the output drift of the scale factor is improved by 0.605 Hz/g in the full temperature range, which is from 0.072 Hz/g to 0.015 Hz/g. The drift of zero bias is improved from 345 mg to 1.9 mg.
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http://dx.doi.org/10.1063/5.0006147DOI Listing
October 2020

sp. nov. and sp. nov., isolated from deep-sea sediment of the South China Sea.

Int J Syst Evol Microbiol 2020 Oct 17;70(10):5576-5585. Epub 2020 Sep 17.

CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, RNAM Center for Marine Microbiology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, Guangdong 510301, PR China.

Two novel Gram-stain-positive bacteria, designated as SCSIO 52909 and SCSIO 52915, were isolated from a deep-sea sediment sample collected at about 3448 m water depth of the South China Sea. Phenotypic, chemotaxonomic and genomic characteristics were investigated. These strains were aerobic and tested positive for catalase activity, oxidase activity and nitrate reduction. Optimal growth occurred at 28 °C, pH 7 and 3% salinity over 14 days cultivation. Its peptidoglycan structure was type A3α (l-Lys-l-Ala) and the only menaquinone was MK-8. Both strains possessed diphosphatidylglycerol, phosphatidylglycerol, an unidentified phosphoglycolipid, an unidentified glycolipid and an unidentified phospholipid. Their major fatty acids differed, but both contained iso-branched components of C 12-methyl. Genome sequencing revealed two large genomes of 4.58 Mbp with G+C content of 67.0 mol% in SCSIO 52909 and of 4.42 Mbp with G+C content of 69.1 % in SCSIO 52915. The two novel strains encoded genes for metabolism that are absent in most other species, and possessed many more gene copy numbers of alkaline phosphatase and thioredoxin reductase. Results of gANI and 16S rRNA gene analyses suggested that the two strains represent two new species, with 74.9, 95.0 % pairwise similarity between each other, and less than 74.3 and 93.5 % to other recognized species, respectively. In the phylogenetic analysis, strains SCSIO 52909 and SCSIO 52915 were separately clustered together and formed a well-separated phylogenetic branch distinct from the other known species in the genus . Based on the data presented here, these two strains should be recognized as two new species in the genus , for which the names sp. nov., with the type strain SCSIO 52909 (=KCTC 49412=CGMCC 1.13853), and sp. nov., with the type strain SCSIO 52915 (=KCTC 49411=CGMCC 1.13852), are proposed.
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http://dx.doi.org/10.1099/ijsem.0.004449DOI Listing
October 2020

Molecular mechanism of olaquindox-induced hepatotoxicity and the hepatic protective role of curcumin.

Food Chem Toxicol 2020 Nov 6;145:111727. Epub 2020 Sep 6.

Department of Pharmacology and Toxicology, College of Veterinary Medicine, China Agricultural University, Yuanmingyuan West Road No.2, Haidian District, Beijing 100193, China. Electronic address:

Olaquindox (OLA) is a chemosynthetic growth promoter, which could promote the treatment of bacterial infections and improve feed energy efficiency. Hepatotoxicity is still a poor feature associated with the adverse effects of OLA. The present study aimed to investigate the molecular mechanism of OLA-induced hepatotoxicity and the protective role of curcumin in mice and HepG2 cells. The result showed that representative biomarkers involved in mitochondrial pathway, p53 pathway, mitogen-activated protein kinase (MAPK) pathway, autophagy and antioxidant pathway were activated. Furthermore, curcumin attenuated OLA-induced serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) and liver damage in mice. In addition, cell viability of HepG2 was enhanced by curcumin pretreatment at 5, 10 and 20 μM. Meanwhile, curcumin markedly ameliorated OLA-induced oxidative stress, apoptosis and mitochondrial dysfunction. Moreover, curcumin pretreatment significantly up-regulated the expressions of nuclear factor erythroid-2-related factor 2 (Nrf2) and heme oxygenase-1(HO-1) and down-regulated the expressions of nuclear factor-kappaB (NF-kB) and p53 through reduced the nuclear translocation of NF-kB induced by OLA. In summary, our findings indicated that OLA-induced hepatotoxicity involved in mitochondrial apoptosis, autophagy, p53 pathway, Nrf2/HO-1 pathways, and curcumin regulated OLA-induced liver damage, oxidative stress and apoptosis via activation of Nrf2/HO-1 pathway and suppression of p53 and NF-kB pathway.
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http://dx.doi.org/10.1016/j.fct.2020.111727DOI Listing
November 2020

A broad-spectrum virus- and host-targeting peptide against respiratory viruses including influenza virus and SARS-CoV-2.

Nat Commun 2020 08 25;11(1):4252. Epub 2020 Aug 25.

Li Ka Shing Faculty of Medicine, State Key Laboratory of Emerging Infectious Diseases, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China.

The 2019 novel respiratory virus (SARS-CoV-2) causes COVID-19 with rapid global socioeconomic disruptions and disease burden to healthcare. The COVID-19 and previous emerging virus outbreaks highlight the urgent need for broad-spectrum antivirals. Here, we show that a defensin-like peptide P9R exhibited potent antiviral activity against pH-dependent viruses that require endosomal acidification for virus infection, including the enveloped pandemic A(H1N1)pdm09 virus, avian influenza A(H7N9) virus, coronaviruses (SARS-CoV-2, MERS-CoV and SARS-CoV), and the non-enveloped rhinovirus. P9R can significantly protect mice from lethal challenge by A(H1N1)pdm09 virus and shows low possibility to cause drug-resistant virus. Mechanistic studies indicate that the antiviral activity of P9R depends on the direct binding to viruses and the inhibition of virus-host endosomal acidification, which provides a proof of concept that virus-binding alkaline peptides can broadly inhibit pH-dependent viruses. These results suggest that the dual-functional virus- and host-targeting P9R can be a promising candidate for combating pH-dependent respiratory viruses.
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http://dx.doi.org/10.1038/s41467-020-17986-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7447754PMC
August 2020

Hyperphosphorylation of fetal liver IGFBP-1 precedes slowing of fetal growth in nutrient-restricted baboons and may be a mechanism underlying IUGR.

Am J Physiol Endocrinol Metab 2020 09 3;319(3):E614-E628. Epub 2020 Aug 3.

Department of Biochemistry, University of Western Ontario, London, Ontario, Canada.

In cultured fetal liver cells, insulin-like growth factor (IGF) binding protein (IGFBP)-1 hyperphosphorylation in response to hypoxia and amino acid deprivation is mediated by inhibition of mechanistic target of rapamycin (mTOR) and activation of amino acid response (AAR) signaling and casein kinase (CK)2. We hypothesized that fetal liver mTOR inhibition, activation of AAR and CK2, and IGFBP-1 hyperphosphorylation occur before development of intrauterine growth restriction (IUGR). Pregnant baboons were fed a control (C) or a maternal nutrient restriction (MNR; 70% calories of control) diet starting at gestational day (GD) 30 (term GD 185). Umbilical blood and fetal liver tissue were obtained at GD 120 (C, = 7; MNR, = 10) and 165 (C, = 7; MNR, = 8). Fetal weights were unchanged at GD 120 but decreased at GD 165 in the MNR group (-13%, = 0.03). IGFBP-1 phosphorylation, as determined by parallel reaction monitoring mass spectrometry (PRM-MS), immunohistochemistry, and/or Western blot, was enhanced in MNR fetal liver and umbilical plasma at GD 120 and 165. IGF-I receptor autophosphorylation (-64%, = 0.05) was reduced in MNR fetal liver at GD 120. Furthermore, fetal liver CK2 (α/α'/β) expression, CK2β colocalization, proximity with IGFBP-1, and CK2 autophosphorylation were greater at GD 120 and 165 in MNR vs. C. Additionally, mTOR complex (mTORC)1 (p-P70S6K, -52%, = 0.05) and mTORC2 (p-Akt, -56%, < 0.001) activity were decreased and AAR was activated (p-GCN2, +117%, = 0.02; p-eIF2α, +294%, = 0.002; p-ERK, +111%, = 0.03) in MNR liver at GD 120. Our data suggest that fetal liver IGFBP-1 hyperphosphorylation, mediated by mTOR inhibition and both AAR and CK2 activation, is a key link between restricted nutrient and oxygen availability and the development of IUGR.
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http://dx.doi.org/10.1152/ajpendo.00220.2020DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7642856PMC
September 2020

Deep Reactive Ion Etching of Z-Cut Alpha Quartz for MEMS Resonant Devices Fabrication.

Micromachines (Basel) 2020 Jul 26;11(8). Epub 2020 Jul 26.

State Key Laboratory for Manufacturing System Engineering, Xi'an Jiaotong University, Xi'an 710049, China.

Quartz is widely used in microelectromechanical systems (MEMS). Especially, MEMS quartz resonators are applied to sensors and serve as sensitive elements. The capability of deep etching is a limitation for the application. Presented in this paper is a deep and high accuracy reactive ion etching method applied to a quartz resonator etching process with a Cr mask. In order to enhance the capability of deep etching and machining accuracy, three kinds of etching gas (CF/Ar, SF/Ar and SF/C4F/Ar), bias power, inductively coupled plasma (ICP) power and chamber pressure were studied in an industrial reactive ion etching machine (GDE C200). Results indicated that the SF/CF/Ar chemistry gas is the suitable and optimal choice. Experiment results indicate that Cr (chromium) mask can obtain a higher selectivity than aluminum and titanium mask. A "sandwich" structure composed of Al layer-Cr layer-Al layer-Cr layer was proposed. The Al (aluminum) film can play the role of releasing stress and protecting gold electrodes, which can enhance the thickness of metal mask. An optimized process using SF/CF/Ar plasmas showed the quartz etching rate of 450 nm/min. Meanwhile, a microchannel with a depth of 75.4 µm is fabricated, and a nearly vertical sidewall profile, smooth surface is achieved.
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http://dx.doi.org/10.3390/mi11080724DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7465086PMC
July 2020

Natural transmission of bat-like SARS-CoV-2PRRA variants in COVID-19 patients.

Clin Infect Dis 2020 Jul 10. Epub 2020 Jul 10.

AIDS Institute, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region, China.

Background: SARS-CoV-2 contains the furin cleavage PRRA motif in the S1/S2 region, which enhances viral pathogenicity but is absent in closely related bat and pangolin coronaviruses. It remains unknown if bat-like coronaviral variants without PRRA (ΔPRRA) can establish natural infection in humans.

Methods: Here, we developed a duplex digital PCR assay to examine ΔPRRA variants in Vero-E6-propagated isolates, human organoids, experimentally infected hamsters and COVID-19 patients.

Results: We found that currently transmitting SARS-CoV-2 contained a quasispecies of wildtype, ΔPRRA variants and upstream variants that have mutations upstream the PRRA motif. Moreover, the ΔPRRA variants were readily detected despite at a low intra-host frequency in transmitted founder viruses in hamsters and in COVID-19 patients including acute cases and a family cluster with a prevalence rate of 52.9%.

Conclusions: Our findings demonstrate that bat-like SARS-CoV-2ΔPRRA not only naturally exists but remains transmissible in COVID-19 patients, which have significant implications to zoonotic origin and natural evolution of SARS-CoV-2.
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http://dx.doi.org/10.1093/cid/ciaa953DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7454488PMC
July 2020

Perinatal maternal undernutrition does not result in offspring capillary rarefaction in the middle-aged male baboon at rest.

J Dev Orig Health Dis 2020 Jun 19:1-5. Epub 2020 Jun 19.

Department of Radiology and Research Imaging Institute, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA.

Microvascular health is a main determinant of coronary blood flow reserve and myocardial vascular resistance. Extracardiac capillary abnormality has been reported in subjects at increased coronary heart disease risk, such as prehypertension, hypertension, diabetes, hyperlipidemia, and atherosclerosis. We have reported cardiovascular dysfunction in a cohort of maternal nutrient reduction (MNR)-induced intrauterine growth restriction (IUGR) baboon offspring. Here we test the hypothesis that there is oral capillary rarefaction associated with MNR-induced IUGR. Capillary density was quantified using in vivo high-power capillaroscopy on seven middle-aged (~10.7 yr; human equivalent ~40 yr) male IUGR baboons and seven male age-matched controls in the lateral buccal and inferior labial mucosa. While no difference was found between groups in either area by fraction area or optical density for these vascular beds derived from fetal preductal vessels, further studies are needed on post-ductal vascular beds, retina, and function.
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http://dx.doi.org/10.1017/S2040174420000550DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7748997PMC
June 2020

gen. nov. sp. nov., a new marine actinobacterium of the family , isolated from South China Sea sediment environments.

Int J Syst Evol Microbiol 2020 Jun 5;70(6):3852-3858. Epub 2020 Jun 5.

CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, CAS RNAM Center for Marine Microbiology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, Guangdong 510301, PR China.

A novel marine actinobacterium, strain SCSIO 58843, was isolated from the sediment sample collected from the South China Sea. Strain SCSIO 58843 was Gram-stain-positive, aerobic and rod shaped. The whole-cell hydrolysis of amino acids contained dd-DAP, alanine, glutamic acid, glycine and aspartic acid. The main menaquinone was MK-9(H). The major fatty acids were Cω and C. The major phospholipids were diphosphatidylglycerol (DPG), phosphatidylinositol (PI), phospatidylcholine (PC) and phosphatidylinositolmannoside (PIM). The G+C content of the genomic DNA was 72.5 %. Phylogenetic analysis of the 16S rRNA gene sequences showed that strain SCSIO 58843 formed a new lineage in the family and had the highest similarity of 93.8 % with DSM 19957. Strain SCSIO 58843 can be distinguished from these known genera in the family by polyphasic data analyses, and represents a novel genus and novel species, for which gen. nov., sp. nov is proposed with the type strain SCSIO 58843(=KCTC 49408=CGMCC 1.17503).
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http://dx.doi.org/10.1099/ijsem.0.004251DOI Listing
June 2020

Infection of bat and human intestinal organoids by SARS-CoV-2.

Nat Med 2020 07 13;26(7):1077-1083. Epub 2020 May 13.

State Key Laboratory of Emerging Infectious Diseases, The University of Hong Kong, Hong Kong, China.

A novel coronavirus-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-emerged in humans in Wuhan, China, in December 2019 and has since disseminated globally. As of April 16, 2020, the confirmed case count of coronavirus disease 2019 (COVID-19) had surpassed 2 million. Based on full-genome sequence analysis, SARS-CoV-2 shows high homology to SARS-related coronaviruses identified in horseshoe bats. Here we show the establishment and characterization of expandable intestinal organoids derived from horseshoe bats of the Rhinolophus sinicus species that can recapitulate bat intestinal epithelium. These bat enteroids are fully susceptible to SARS-CoV-2 infection and sustain robust viral replication. Development of gastrointestinal symptoms in some patients with COVID-19 and detection of viral RNA in fecal specimens suggest that SARS-CoV-2 might cause enteric, in addition to respiratory, infection. Here we demonstrate active replication of SARS-CoV-2 in human intestinal organoids and isolation of infectious virus from the stool specimen of a patient with diarrheal COVID-19. Collectively, we established the first expandable organoid culture system of bat intestinal epithelium and present evidence that SARS-CoV-2 can infect bat intestinal cells. The robust SARS-CoV-2 replication in human intestinal organoids suggests that the human intestinal tract might be a transmission route of SARS-CoV-2.
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http://dx.doi.org/10.1038/s41591-020-0912-6DOI Listing
July 2020

Placental fatty acid transport across late gestation in a baboon model of intrauterine growth restriction.

J Physiol 2020 06 29;598(12):2469-2489. Epub 2020 May 29.

Department of Pediatrics, Section of Neonatology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA.

Key Points: Intrauterine growth restriction (IUGR) is associated with perinatal morbidity and increased risk of lifelong disease, including neurodevelopmental impairment. Fatty acids (FA) are critical for normal brain development, although their transport across the placenta in IUGR pregnancies is poorly understood. The present study used a baboon model of IUGR (maternal nutrient restriction, MNR) to investigate placental expression of FA transport and binding proteins, and to determine gestational age-related changes in maternal and fetal plasma FA concentrations. We found MNR to be associated with increased placental expression of FA binding and transport proteins in late gestation, with fetal plasma FA concentrations that were similar to those of control animals. The present study is the first to report a profile of fetal and maternal plasma FA concentrations in a baboon model of growth restriction with data that suggest adaptation of placental transport to maintain delivery of critically needed FA.

Abstract: Intrauterine growth restriction (IUGR) is associated with specific changes in placental transport of amino acids, folate and ions. However, little is known about placental fatty acid (FA) transport in IUGR. We hypothesized that placental FA transport proteins (FATP) and FA binding proteins (FABP) are up-regulated and fetal plasma FA concentrations are decreased at term in a baboon model of IUGR. Pregnant baboons were fed control or maternal nutrient restricted (MNR) diet (70% of control calories) from gestation day (GD) 30 (term 184 days). Plasma and placental samples were collected at GD120 (control n = 8, MNR n = 9), GD140 (control n = 6, MNR n = 7) and GD170 (control n = 6, MNR n = 6). Placentas were homogenized, and syncytiotrophoblast microvillous plasma membrane (MVM) and basal plasma membranes (BM) were isolated. Protein expression of FABP1, 3, 4 and 5 (homogenate) and FATP2, 4, and 6 (MVM, BM) was determined by Western blotting. FA content in maternal and umbilical vein plasma was measured by gas chromatography-mass spectrometry. Placental FABP1 and FABP5 expression was increased in MNR compared to controls at GD170, as was MVM FATP2 and FATP6 expression at GD140 and FATP2 expression at GD170. BM FATP4 and FATP6 expression was increased in MNR at GD140. Fetal plasma FA concentrations were similar in controls and MNR. These data suggest the adaptation of placental transport when aiming to maintain delivery of critically needed FAs for fetal growth and brain development.
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http://dx.doi.org/10.1113/JP279398DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7384518PMC
June 2020

Research on a Micro-Processing Technology for Fabricating Complex Structures in Single-Crystal Quartz.

Micromachines (Basel) 2020 Mar 24;11(3). Epub 2020 Mar 24.

State Key Laboratory for Manufacturing Systems Engineering, Xi'an Jiaotong University, Xi'an 710049, China.

Single-crystal quartz material is widely applied in the manufacture of resonators and sensors, but it is difficult to process because of its high hardness. A novel way to fabricate single-crystal quartz structures is proposed in this paper; the method includes quartz-on-silicon (QoS) technology and inductively coupled plasma (ICP) etching, which makes it feasible to fabricate complex structures with crystal quartz. The QoS method encompasses the bonding of silicon and quartz, followed by the thinning and polishing of quartz, which can enable the fabrication of an ultra-thin quartz wafer on silicon. In this way, instead of the conventional wet etching with hydrofluoric acid, the quartz layer can be easily etched using the ICP dry-etching method. Then, the structure of the pure quartz material is obtained by removing the silicon wafer. In addition, the silicon layer can be processed into the appropriate structure. This aspect overcomes the difficulty of processing a complex structure of single-crystal quartz with different crystal orientations. Thin single-crystal quartz wafers of Z-cut with a thickness of less than 40 μm were obtained by using this method, and a complex three-dimensional structure with an 80 μm width was also acquired by the ICP etching of the quartz wafer. The method can be applied to make both crystal-oriented quartz-based sensors and actuators, such as quartz resonant accelerometers.
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http://dx.doi.org/10.3390/mi11030337DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7143568PMC
March 2020

MPA-CdTe quantum dots as "on-off-on" sensitive fluorescence probe to detect ascorbic acid via redox reaction.

Spectrochim Acta A Mol Biomol Spectrosc 2020 Jun 9;234:118249. Epub 2020 Mar 9.

School of Chemistry and Chemical Engineering, Anhui University, Hefei 230601, China; AnHui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials, Anhui University, Hefei 230601, China; Anhui Province Key Laboratory of Environment-friendly Polymer Materials, Anhui University, Hefei 230601, China. Electronic address:

Mercaptopropionic acid (MPA) capped CdTe quantum dots (MPA-CdTe QDs) were synthesized in aqueous medium by hydrothermal method, which modified by Fe could be used as a fluorescent probe to detect ascorbic acid (AA). MPA-CdTe QDs fluorescence probe could be used as successive sensor for metal ions and AA with "on-off-on" process. The fluorescence of QDs was quenched after adding Fe to MPA-CdTe QDs. Then, the fluorescence of the Fe@MPA-CdTe QDs can be sensitively turned on by AA to give an "on-off-on" fluorescence response according to the oxidation-reduction between Fe and AA. There was a linear relationship between fluorescence intensity quenching value and the concentration of Fe in the range of 2-10 μM since Fe sensitively reacted with CdTe QDs. The linear detection range for AA was 0.1-1 μM with a limit of detection of 6.6 nM. The principle is proved by fluorescence emission spectroscopy, nuclear magnetic resonance spectroscopy. The proposed method is successfully used to detect the AA in human plasma sample.
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http://dx.doi.org/10.1016/j.saa.2020.118249DOI Listing
June 2020

Association of novel markers of liver disease with neonatal liver disease in premature baboons, Papio sp.

PLoS One 2020 9;15(3):e0228985. Epub 2020 Mar 9.

Department of Pediatrics, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States of America.

Parenteral Nutrition (PN) Associated Liver Disease (PNALD) affects up to 60% of neonates; however, techniques for diagnosing and monitoring disease progression remain limited. The neonatal baboon model may provide a unique opportunity to identify serologic markers associated with this disease. The purpose of this study was to investigate if Hyaluronic Acid (HA), TIMP metallopeptidase inhibitor 1 (TIMP1), Amino-terminal Propeptide of Type-III Collagen (PIIINP) and Enhanced Liver Fibrosis (ELF) score associate with histological liver disease in neonatal baboons exposed to PN. Preterm baboons delivered via c-section at 67% gestation received PN for 14 days with or without Intralipid (PRT+IL, PRT-IL, respectively) or were sacrificed after birth (PRTCTR). Term baboons were sacrificed after birth (TERMCTR) or survived 14 days (TERM+14d). Serum HA, TIMP1, and PIIINP concentrations were measured by ELISA. A blinded pathologist assigned liver histological scores following necropsy. HA increased 9.1-fold, TIMP1 increased 2.2-fold, and ELF score increased 1.4-fold in PRT-IL compared to PRTCTR. ALT, AST, and GGT were within normal limits and did not vary between groups. A trend towards increased fibrosis was found in PRT-IL baboons. Microvesicular hepatocyte steatosis and Kupffer cell hypertrophy were elevated in PRT-IL vs PRTCTR. HA and TIMP1 were significantly elevated in preterm baboons with early histological findings of liver disease evidenced by hepatic steatosis, Kupffer cell hypertrophy and a trend towards fibrosis whereas traditional markers of liver disease remained normal. These novel markers could potentially be utilized for monitoring early hepatic injury in neonates.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0228985PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7062281PMC
June 2020

Improved lead removal from aqueous solution using novel porous bentonite - and calcite-biochar composite.

Sci Total Environ 2020 Mar 18;709:136171. Epub 2019 Dec 18.

Research Group for Advanced Materials & Sustainable Catalysis (AMSC), State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology, College of Chemical Engineering, Zhejiang University of Technology, Hangzhou 310014, China; Qing Yang Institute for Industrial Minerals, You Hua, Qing Yang 242804, An Hui, China. Electronic address:

Biochar-mineral (bentonite/calcite) composite (BC-CM) prepared at different temperatures were tested under varied conditions for effective removal of lead (Pb) from aqueous solution. With increasing pyrolysis temperature, increased surface area, pore volume, bentonite decomposition and less or no decomposition of calcite occurred. Bentonite-biochar (BCS) and calcite-biochar (CCS) prepared at 700 °C were found most suitable for efficient removal of Pb (99.9%). Bentonite and calcite acted as catalyst and contributed to changes in yield, pH, texture, functional groups, minerals and carbonization that facilitated efficient Pb removal by BCS 700 and CCS 700. Pb concentration, pH, dose of BCS and CCS, and contact time were further optimized using response surface methodology (RSM) for maximizing removal percentage (R%) of Pb and adsorption capacity (qt). Both BCS 700 and CCS 700 showed similar effects (positive/negative) of factors on R% and qt. Under optimized conditions, 0.21 g of BCS 700 effectively removed 99.2% of 431 mg/L in 3.6 h at solution pH of 4.2, while 0.07 g CCS 700 removed 97.06% of 232 mg/L in 3.5 h at 5.5 pH. Removal of Pb onto both BCS and CCS was by monolayer adsorption with maximum adsorption capacity of 500 mg/g. Rapid Pb removal was observed within 2 h of contact time (CCS 700 > BCS 700) and equilibrium was achieved within 10 h. BCS 700 followed first order and CCS 700 followed second order kinetic model. Electrostatic attraction between Pb ions and mineral groups present in BCS 700 and CCS 700 also played important role in Pb removal. This study clearly demonstrated that composite of biochar with bentonite or calcite under optimized conditions significantly improved Pb removal and adsorption capacity that can be further utilized for larger scale applications.
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http://dx.doi.org/10.1016/j.scitotenv.2019.136171DOI Listing
March 2020

AIE-active fluorescent polymeric nanoparticles about dextran derivative: preparation and bioimaging application.

J Biomater Sci Polym Ed 2020 03 12;31(4):504-518. Epub 2019 Dec 12.

School of Chemistry and Chemical Engineering, Anhui University, Hefei, PR China.

Aggregation-induced emission (AIE), as a special phenomenon of fluorescence, can elegantly overcome the fluorescence quenching caused by common fluorescent materials under high concentration conditions and has attracted interest of researchers in many fields. Particularly AIE-active polymer nanoparticles have been widely utilized in a modern biomedical research. In this work, we prepared a novel kind of AIE-active fluorescent polymeric nanoparticals (Dex-OH-CHO) through a facile esterification between a new hydrophobic AIE-active 1, 8-naphthalimide derivative and the hydrophilic dextran. The structure and optical properties of Dex-OH-CHO were characterized in detail by FTIR, H NMR, XPS, TEM and fluorescence spectra. The results showed that Dex-OH-CHO emitted light-blue fluorescence in aqueous solution with high fluorescent quantum yield (Φ = 24.43%, concentration is 20 μg/mL), low CMC (5 μg/mL), good photostability, high water solubility and well dispersivity. Moreover, good biocompatibility and ideal cell uptake made Dex-OH-CHO had a great application potential in biological imaging.
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http://dx.doi.org/10.1080/09205063.2019.1702277DOI Listing
March 2020

gen. nov., sp. nov., isolated from a deep-sea hydrothermal sediment in the West Pacific Ocean.

Int J Syst Evol Microbiol 2019 Nov;69(11):3362-3367

CAS Key Laboratory of Tropical Marine Bio-resources and Ecology; Guangdong Key Laboratory of Marine Materia Medica; RNAM Center for Marine Microbiology; South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, Guangdong 510301, PR China.

A novel Gram-stain-negative bacterium, designated as SCSIO 06110, was isolated from a deep-sea sediment of the West Pacific Ocean. Cells were 0.5-0.8 µm in width and 3.0-4.0 µm in length, spore-forming, rod-shaped with peritrichous flagella. Positive for catalase and urease, negative for oxidase and nitrate reduction. Growth occurred at 15-37 °C, pH 6-9 and 1-5 % (w/v) NaCl, with optimum growth at 28 °C, pH 7 and 3 % (w/v) NaCl. MK-7 was the only menaquinone. The strain possessed diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and two unidentified phospholipids. Iso-C, iso-C and iso-C were the major fatty acids. The novel isolate clustered with genera in the family , but formed a separated branch with the closest relative J15A17 (91.1 % sequence similarity) when compared in a phylogenetic analysis of 16S rRNA gene sequences. The DNA G+C content of strain SCSIO 06110 was 38.5 mol%. Based on the polyphasic data presented, a new genus, gen. nov., is proposed in the family with the type species sp. nov. and the type strain SCSIO 06110 (=DSM 105158=CGMCC 1.16550).
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http://dx.doi.org/10.1099/ijsem.0.003526DOI Listing
November 2019

Strength of nonhuman primate studies of developmental programming: review of sample sizes, challenges, and steps for future work.

J Dev Orig Health Dis 2020 06 30;11(3):297-306. Epub 2019 Sep 30.

Department of Animal Science, University of Wyoming, Laramie, WY, USA.

Nonhuman primate (NHP) studies are crucial to biomedical research. NHPs are the species most similar to humans in lifespan, body size, and hormonal profiles. Planning research requires statistical power evaluation, which is difficult to perform when lacking directly relevant preliminary data. This is especially true for NHP developmental programming studies, which are scarce. We review the sample sizes reported, challenges, areas needing further work, and goals of NHP maternal nutritional programming studies. The literature search included 27 keywords, for example, maternal obesity, intrauterine growth restriction, maternal high-fat diet, and maternal nutrient reduction. Only fetal and postnatal offspring studies involving tissue collection or imaging were included. Twenty-eight studies investigated maternal over-nutrition and 33 under-nutrition; 23 involved macaques and 38 baboons. Analysis by sex was performed in 19; minimum group size ranged from 1 to 8 (mean 4.7 ± 0.52, median 4, mode 3) and maximum group size from 3 to 16 (8.3 ± 0.93, 8, 8). Sexes were pooled in 42 studies; minimum group size ranged from 2 to 16 (mean 5.3 ± 0.35, median 6, mode 6) and maximum group size from 4 to 26 (10.2 ± 0.92, 8, 8). A typical study with sex-based analyses had group size minimum 4 and maximum 8 per sex. Among studies with sexes pooled, minimum group size averaged 6 and maximum 8. All studies reported some significant differences between groups. Therefore, studies with group sizes 3-8 can detect significance between groups. To address deficiencies in the literature, goals include increasing age range, more frequently considering sex as a biological variable, expanding topics, replicating studies, exploring intergenerational effects, and examining interventions.
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http://dx.doi.org/10.1017/S2040174419000539DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7103515PMC
June 2020

Activation of C-Type Lectin Receptor and (RIG)-I-Like Receptors Contributes to Proinflammatory Response in Middle East Respiratory Syndrome Coronavirus-Infected Macrophages.

J Infect Dis 2020 02;221(4):647-659

State Key Laboratory of Emerging Infectious Diseases, Pokfulam, Hong Kong.

Background: Human infection with Middle East respiratory syndrome coronavirus (MERS-CoV) poses an ongoing threat to public health worldwide. The studies of MERS patients with severe disease and experimentally infected animals showed that robust viral replication and intensive proinflammatory response in lung tissues contribute to high pathogenicity of MERS-CoV. We sought to identify pattern recognition receptor (PRR) signaling pathway(s) that mediates the inflammatory cascade in human macrophages upon MERS-CoV infection.

Methods: The potential signaling pathways were manipulated individually by pharmacological inhibition, small interfering ribonucleic acid (siRNA) depletion, and antibody blocking. The MERS-CoV-induced proinflammatory response was evaluated by measuring the expression levels of key cytokines and/or chemokines. Reverse transcription-quantitative polymerase chain reaction assay, flow cytometry analysis, and Western blotting were applied to evaluate the activation of related PRRs and engagement of adaptors.

Results: MERS-CoV replication significantly upregulated C-type lectin receptor (CLR) macrophage-inducible Ca2+-dependent lectin receptor (Mincle). The role of Mincle for MERS-CoV-triggered cytokine/chemokine induction was established based on the results of antibody blockage, siRNA depletion of Mincle and its adaptor spleen tyrosine kinase (Syk), and Syk pharmacological inhibition. The cytokine and/or chemokine induction was significantly attenuated by siRNA depletion of retinoic acid-inducible-I-like receptors (RLR) or adaptor, indicating that RLR signaling also contributed to MERS-CoV-induced proinflammatory response.

Conclusions: The CLR and RLR pathways are activated and contribute to the proinflammatory response in MERS-CoV-infected macrophages.
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http://dx.doi.org/10.1093/infdis/jiz483DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7107474PMC
February 2020

A high sensitivity quartz resonant pressure sensor with differential output and self-correction.

Rev Sci Instrum 2019 Jun;90(6):065003

State Key Laboratory for Manufacturing System Engineering, Xi'an Jiaotong University, Xi'an, Shanxi 710049, People's Republic of China.

A high sensitivity quartz resonant pressure sensor with differential output and self-correction is proposed. Although compared to other resonant devices, quartz resonators have less influence on external environmental factors due to their own high quality factor Q; the influence of external environment such as temperature, vibration, and humidity cannot be ignored in high-precision applications. These errors need to be eliminated or compensated. Therefore, this paper divides the core unit of the sensor into two parts: the working unit and the reference unit. The working unit provides the differential outputs which not only improves the sensitivity but also suppresses some interference such as time drift and temperature drift, and it is rarely used in quartz resonant pressure sensors. The reference unit can effectively detect and offset the interference of temperature and vibration which is named as self-correction, and it can also provide temperature measurement. Double-ended tuning fork quartz resonators used in both units are manufactured by micromachining technology. Bellows and flexible mechanisms used as pressure conversion units are manufactured using modern mechanical technology. The test results show that the sensor has the conformity accuracy of the fitting formula of 0.0148% full scale (FS), the good basic accuracy of 0.06% FS, and the high sensitivity of 36.58 Hz/kPa which meets well with the theoretical result. It is shown by the experiments that the reference unit can effectively correct the interference of temperature and vibration. The theoretical analysis and experimental results prove the feasibility of the resonant pressure sensor which can meet the application requirements of pressure measurement in the high-tech industries.
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http://dx.doi.org/10.1063/1.5094212DOI Listing
June 2019

Effect of maternal baboon (Papio sp.) dietary mismatch in pregnancy and lactation on post-natal offspring early life phenotype.

J Med Primatol 2019 08 26;48(4):226-235. Epub 2019 Apr 26.

Department of Animal Sciences, Texas Pregnancy and Life-course Health Center, University of Wyoming, Laramie, Wyoming.

Background: Non-human primate models of developmental programing by maternal mismatch between pregnancy and lactation diets are needed for translation to human programing outcomes. We present baboon offspring morphometry from birth to 3 years, and blood cortisol and adrenocorticotropin (ACTH) from 2 to 24 months.

Methods: Control mothers ate chow; mismatch mothers ate 30% less than controls during pregnancy and high-fat high-energy diet through lactation.

Results: Mismatch mothers lost weight during pregnancy. At birth, there were trends toward lower weight in mismatch offspring of both sexes (P = 0.06). From 0-3 years, catch-up growth occurred. Mismatch offspring male and female body weight increased faster than controls (P < 0.001). Mismatch female offspring showed greater increase in BMI (P < 0.001) and abdominal circumference (P = 0.008) vs controls. ACTH and cortisol slopes from 2 to 24 months of age were similar between groups in both sexes. Cortisol and ACTH increased after weaning in all groups.

Conclusions: Mismatch produces sexually dimorphic post-natal growth phenotypes.
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http://dx.doi.org/10.1111/jmp.12415DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6610582PMC
August 2019

Ontogeny and programming of the fetal temporal cortical endocannabinoid system by moderate maternal nutrient reduction in baboons (Papio spp.).

Physiol Rep 2019 03;7(6):e14024

Department of Obstetrics and Gynecology, Texas Tech University Health sciences Center at the Permian Basin, Odessa, Texas.

Poor nutrition during pregnancy is a worldwide public health problem. Maternal nutrient reduction (MNR) is associated with maternal and fetal stress and a sex-dependent decrease in nonhuman primate (NHP) cognitive performance. Early life stress potentiates epileptogenesis in a sex-specific manner, and temporal lobe (TL) epilepsy is associated with neurocognitive disorders. The endogenous cannabinoid system (ECS) demonstrates remarkable developmental changes and plays a key role in aging-related diseases (e.g., dementia). Baboons have been studied as a natural model of epilepsy and express all ECS system components. We therefore evaluated baboon fetal temporal cortex ECS ontogenic and MNR-dependent changes. At 120 days gestational age (dGA) (term 185 days), maternal, fetal, and placental morphometry were similar between control and MNR pregnancies. MNR maternal weight gain was decreased compared with controls at 165 dGA independent of fetal sex. In male fetuses, expression of ECS synthesizing and degrading enzymes was gestational age-dependent, with the exception of fatty acid amide hydrolase (FAAH). MNR had a sex-specific effect on the protein expression of CB1R during development: CB1R protein expression was decreased in fetal temporal cortex of male fetuses at 120 and 140 dGA. Our data reveal that the MNR has sex-specific effects on temporal cortical expression of the ECS in baboon offspring and shows vulnerability of ECS in male fetuses during gestation.
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http://dx.doi.org/10.14814/phy2.14024DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6434170PMC
March 2019