Publications by authors named "Tianyi Li"

128 Publications

Molecular surveillance of HIV-1 newly diagnosed infections in Shenzhen, China from 2011 to 2018.

J Infect 2021 Apr 28. Epub 2021 Apr 28.

Department of AIDS Research, State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071, China. Electronic address:

Objectives: Shenzhen is suffering severe HIV epidemic. No systematic surveillance on high risk populations, HIV genetic diversity, transmitted drug resistance (TDR) and molecular transmission clusters (MTCs) have been reported yet. In this study, we described them based on newly diagnosed HIV positive cases from 2011 to 2018 in Shenzhen city, China.

Methods: Plasma samples of newly reported HIV positive cases in Shenzhen, China were collected from 2011 to 2018. The HIV pol gene was amplified and sequenced for subtyping, genetic characterization, TDR and phylogenetic analysis. Demographic and risk characteristics associated with transmitted drug resistance-associated mutations (TDRAMs) and MTCs were explored by using logistic regression analyses.

Results: 10378 HIV pol sequences were successfully obtained from newly diagnosed patients with available background information. The most prevalent HIV-1 subtype was CRF07_BC (40.92%). CRF07_BC, CRF55_01B and URFs increased across years. Total TDR was 6.02% during 2011 to 2018. CRF01_AE, CRF08_BC, CRF55_01B and subtype B were more likely to be associated with TDRAMs than CRF07_BC. 4460 (42.98%) patients were infected with strains included in MTCs. Patients younger than 30 and over 50 years were more likely to cluster.

Conclusions: The prevalence of HIV-1 drug resistance and molecular transmission clusters in Shenzhen should raise a high alert. Interventions targeting on patients with strains locating in MTCs should be considered to improve prevention effect in Shenzhen.
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http://dx.doi.org/10.1016/j.jinf.2021.04.021DOI Listing
April 2021

Integrated Screening of Effective Anti-Insomnia Fractions of Zhi-Zi-Hou-Po Decoction via and Network Pharmacology Analysis of the Underlying Pharmacodynamic Material and Mechanism.

ACS Omega 2021 Apr 24;6(13):9176-9187. Epub 2021 Mar 24.

School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing 102488, China.

Insomnia is an anabatic epidemiology, while the mechanism is extremely complicated; it remains one of the major scientific challenges in life sciences. Because of the advantage of having a similar genetic background and circadian rhythm as those of humans, the model organism is hugely popular in sleep-related drug screening studies. Seven-day-old virgin was used to establish the sleep deprivation model by repeated light stimulation at night. Using PySolo activity monitoring system and activity as indices, the effective fractions of Zhi-Zi-Hou-Po decoction (ZZHPD) for insomnia were screened; the content of monoamine neurotransmitters dopamine (DA), 5-hydroxyindole-3-acetic acid (5-HIAA), Homovanillic acid (HVA), and 5-hydroxytryptamine (5-HT) in the brain of were determined by high-performance liquid chromatography-electro-chemical detection. The herb-compound-target-disease target network were further constructed through network pharmacology to identify the potential targets and pathways of ZZHPD in the intervention of insomnia. Finally, the molecular docking method was used for evaluating the binding characteristics of important compounds from ZZHPD with related targets. The results showed that a certain dose of ZZHPD and its petroleum ether, dichloromethane, ethyl acetate, and -butanol fractions could improve sleep. The dichloromethane fraction from ZZHPD extracts showed the best anti-insomnia effect among all extracts. It can also reduce the content of DA and HVA in the brain of and increase 5-HT and 5-HIAA levels. The network pharmacology showed that the main active ingredients in ZZHPD included magnolol, honokiol, hesperidin, and so forth. According to the screening conditions, there were 71 targets and the result of KEGG enrichment analysis revealed that 73 pathways were associated with insomnia, which were primarily involved in inflammatory response, central neurotransmitter regulation, and apoptosis to relieve insomnia. The molecular docking results clarified that naringenin and apigenin have an intimate relationship with GABA receptor, histamine H1, orexin receptor type 2, and interleukin-6. The mechanism of relieving insomnia is the result of the interaction of multi-components, multi-targets, and multi-pathways, which provides a certain theoretical basis for the treatment of insomnia and related diseases as well as clinical research.
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http://dx.doi.org/10.1021/acsomega.1c00445DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8028125PMC
April 2021

Computer-Aided Diagnosis of COVID-19 CT Scans Based on Spatiotemporal Information Fusion.

J Healthc Eng 2021 3;2021:6649591. Epub 2021 Mar 3.

College of Optoelectronic Science and Engineering, Soochow University, Suzhou, Jiangsu 215006, China.

Coronavirus disease (COVID-19) is highly contagious and pathogenic. Currently, the diagnosis of COVID-19 is based on nucleic acid testing, but it has false negatives and hysteresis. The use of lung CT scans can help screen and effectively monitor diagnosed cases. The application of computer-aided diagnosis technology can reduce the burden on doctors, which is conducive to rapid and large-scale diagnostic screening. In this paper, we proposed an automatic detection method for COVID-19 based on spatiotemporal information fusion. Using the segmentation network in the deep learning method to segment the lung area and the lesion area, the spatiotemporal information features of multiple CT scans are extracted to perform auxiliary diagnosis analysis. The performance of this method was verified on the collected dataset. We achieved the classification of COVID-19 CT scans and non-COVID-19 CT scans and analyzed the development of the patients' condition through the CT scans. The average accuracy rate is 96.7%, sensitivity is 95.2%, and F1 score is 95.9%. Each scan takes about 30 seconds for detection.
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http://dx.doi.org/10.1155/2021/6649591DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7954614PMC
April 2021

Integrating UPLC-QE-Orbitrap-MS technology and network pharmacological method to reveal the mechanism of Bailemian capsule to relieve insomnia.

Nat Prod Res 2021 Mar 17:1-5. Epub 2021 Mar 17.

School of Chinese Materia Medica, Beijing University of Chinese Medicine, Beijing, China.

Bailemian capsule (BLMC) is a Chinese patent drug for treating insomnia with excellent curative effects. But there are few researches on it. In this research, a rapid separation and identification method using UPLC-QE-Orbitrap-MS was established, and 228 identified compounds were separated within 18 min. The structures of compounds were preliminarily determined by comparing the retention time and fragmentation law. Furthermore, multiple databases were used to integrate the compound targets of BLMC and the disease targets related to insomnia. After the intersection of the two sets of targets, a protein-protein interaction network and a drug-target-disease pharmacological network were established, then using the DAVID database to perform GO analysis and KEGG analysis on the common targets to find related pathways. Finally, a total of 289 common targets and 136 pathways were found to participate in the mechanism.
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http://dx.doi.org/10.1080/14786419.2021.1900176DOI Listing
March 2021

Childhood ischaemic stroke in the basal ganglia can lead to fine motor and anxiety disorders: a retrospective analysis and follow-up of 109 cases.

BMC Neurol 2021 Feb 20;21(1):84. Epub 2021 Feb 20.

Department of Neurology, Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Children's Hospital of Chongqing Medical University, Chongqing, P.R. China.

Background: Stroke in children easily causes long-term dysfunction. Whether the prognoses of motor and anxiety disorders are related to the affected stroke area has not been reported.

Methods: One hundred nine cases of children with ischaemic stroke were reviewed and divided into three groups: lenticular nucleus lesions only (lenticular nucleus group), lenticular nucleus and caudate head lesions (caudate head group), and lenticular nucleus and thalamus lesions (thalamus group). Overall prognosis was evaluated by the mRS score. The SCAS-P was used to evaluate anxiety in children aged ≥6 years.

Results: mRS scores were ≤ 2 points (mean: 0.62), no significant difference among groups. 3/21 (14.2%) patients in the caudate head group changed handedness, which is significantly higher than other groups. Patients with lesions in thalamus group had significantly higher SCAS-P scores.

Conclusions: The overall prognosis of children with basal ganglia ischaemic stroke is good. However, hand preference changes and anxiety disorders may develop. Patients in the caudate head groups are more likely to suffer from fine motor disorders and changes in handedness. Patients within the thalamus group are more prone to anxiety than patients in the other groups. Anxiety disorders should be noted in children with basal ganglia stroke.
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http://dx.doi.org/10.1186/s12883-021-02112-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7896398PMC
February 2021

V374A KCND3 Pathogenic Variant Associated With Paroxysmal Ataxia Exacerbations.

Neurol Genet 2021 Feb 6;7(1):e546. Epub 2021 Jan 6.

Department of Clinical Neuroscience (M.P., R.Å., T.L., Å.B., J.N., P.S.), Department of Molecular Medicine and Surgery (D.N.), Center for Molecular Medicine (D.N.), and Science for Life Laboratory (D.N.), Karolinska Institutet (S.L., I.S.), Stockholm; Department of Neurology (M.P., J.W., P.S.), Department of Clinical Genetics (D.N.), Department of Nuclear Medicine (I.S.), and Department of Neurophysiology (J.N.), Karolinska University Hospital (R.Å.), Stockholm; Department of Integrative Medical Biology (K.S.), Umeå University; and Department of Medical Sciences (J.N.), Örebro University, Sweden.

Objective: Ataxia channelopathies share common features such as slow motor progression and variable degrees of cognitive dysfunction. Mutations in potassium voltage-gated channel subfamily D member 3 (), encoding the K+ channel, Kv4.3, are associated with spinocerebellar ataxia (SCA) 19, allelic with SCA22. Mutations in potassium voltage-gated channel subfamily C member 3 (), encoding another K+ channel, Kv3.3, cause SCA13. First, a comprehensive phenotype assessment was carried out in a family with autosomal dominant ataxia harboring 2 genetic variants in and . To evaluate the physiological impact of these variants on channel currents, in vitro studies were performed.

Methods: Clinical and psychometric evaluations, neuroimaging, and genotyping of a family (mother and son) affected by ataxia were carried out. Heterozygous and homozygous Kv3.3 A671V and Kv4.3 V374A variants were evaluated in oocytes using 2-electrode voltage-clamp. The influence of Kv4 conductance on neuronal activity was investigated computationally using a Purkinje neuron model.

Results: The main clinical findings were consistent with adult-onset ataxia with cognitive dysfunction and acetazolamide-responsive paroxysmal motor exacerbations in the index case. Despite cognitive deficits, fluorodeoxyglucose (FDG)-PET displayed hypometabolism mainly in the severely atrophic cerebellum. Genetic analyses revealed the new variant c.1121T>C (V374A) in and c.2012T>C (A671V) in . In vitro electrophysiology experiments on oocytes demonstrated that the V374A mutant was nonfunctional when expressed on its own. Upon equal co-expression of wild-type (WT) and V374A channel subunits, Kv4.3 currents were significantly reduced in a dominant negative manner, without alterations of the gating properties of the channel. By contrast, Kv3.3 A671V, when expressed alone, exhibited moderately reduced currents compared with WT, with no effects on channel activation or inactivation. Immunohistochemistry demonstrated adequate cell membrane translocation of the Kv4.3 V374A variant, thus suggesting an impairment of channel function, rather than of expression. Computational modeling predicted an increased Purkinje neuron firing frequency upon reduced Kv4.3 conductance.

Conclusions: Our findings suggest that Kv4.3 V374A is likely pathogenic and associated with paroxysmal ataxia exacerbations, a new trait for SCA19/22. The present FDG PET findings contrast with a previous study demonstrating widespread brain hypometabolism in SCA19/22.
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http://dx.doi.org/10.1212/NXG.0000000000000546DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7862093PMC
February 2021

Exoskeleton Follow-Up Control Based on Parameter Optimization of Predictive Algorithm.

Appl Bionics Biomech 2021 21;2021:8850348. Epub 2021 Jan 21.

Shanghai Huangpu District Fire Rescue Detachment, Shanghai 200001, China.

The prediction of sensor data can help the exoskeleton control system to get the human motion intention and target position in advance, so as to reduce the human-machine interaction force. In this paper, an improved method for the prediction algorithm of exoskeleton sensor data is proposed. Through an algorithm simulation test and two-link simulation experiment, the algorithm improves the prediction accuracy by 14.23 ± 0.5%, and the sensor data is smooth. Input the predicted signal into the two-link model, and use the calculated torque method to verify the prediction accuracy data and smoothness. The simulation results showed that the algorithm can predict the joint angle of the human body and can be used for the follow-up control of the swinging legs of the exoskeleton.
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http://dx.doi.org/10.1155/2021/8850348DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7843196PMC
January 2021

In-Situ Characterization of Dynamic Morphological and Phase Changes of Selenium-doped Germanium Using a Single Particle Cell and Synchrotron Transmission X-ray Microscopy.

ChemSusChem 2021 Mar 2;14(5):1370-1376. Epub 2021 Feb 2.

Department of Mechanical and Energy Engineering, Indiana University Purdue, University Indianapolis, Indianapolis, IN 46202, USA.

The dynamic information of lithium-ion battery active materials obtained from coin cell-based in-situ characterizations might not represent the properties of the active material itself because many other factors in the cell could have impacts on the cell performance. To address this problem, a single particle cell was developed to perform the in-situ characterization without the interference of inactive materials in the battery electrode as well as the X-ray-induced damage. In this study, the dynamic morphological and phase changes of selenium-doped germanium (Ge Se ) at the single particle level were investigated via synchrotron-based in-situ transmission X-ray microscopy. The results demonstrate the good reversibility of Ge Se at high cycling rate that helps understand its good cycling performance and rate capability. This in-situ and operando technique based on a single particle battery cell provides an approach to understanding the dynamic electrochemical processes of battery materials during charging and discharging at the particle level.
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http://dx.doi.org/10.1002/cssc.202002776DOI Listing
March 2021

Phylogenetic Analysis of Sequences in the HIV Database Revealed Multiple Potential Circulating Recombinant Forms in China.

AIDS Res Hum Retroviruses 2021 Feb 1. Epub 2021 Feb 1.

Department of AIDS Research, State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China.

HIV recombination contributes greatly to its diversity and produces many circulating recombinant forms (CRFs) and unique recombinant forms (URFs). In China, 24 CRFs have been reported to date, and CRFs cause more than 80% of HIV infections. However, the prevalence of CRFs might still be underestimated, as a high level of onward transmission of URFs has been reported. In this study, we analyzed all Chinese region (2,253-3,252) sequences in the HIV Database to evaluate potential new CRFs in China. HIV-1 genotypes were verified by the Context-based Modeling for Expeditious Typing (COMET) tool. Maximum-likelihood (ML) trees were constructed based on sequences with unassigned genotypes. Cluster Picker 1.2.1 was used to identify transmission clusters. Meanwhile, a jumping-profile hidden Markov model (jpHMM) was used to perform recombination breakpoint analysis. Beast 1.7.5 was used to estimate the time of the most recent common ancestor of new CRFs. In the HIV databases, CRF01_AE was the most prevalent genetic form in China, accounting for 39.69% of all national infections, followed by CRF07_BC (20.47%), subtype B (17.50%), CRF08_BC (6.60%), subtype C (6.28%), CRF55_01B (2.06%), and other CRFs (1.77%). The URFs were responsible for 5.31% of all infections nationwide. Among URFs, genomes comprising BC, 01BC, 01B, and 01C were dominant. Finally, 17 potential CRFs and 1 novel CRF were identified. BEAST analysis indicates that novel CRF originated around in 2009. The data highlight that more CRFs have been spreading in China. HIV-1 sequences that are commonly used to explore drug resistance are helpful for the surveillance of epidemics of different HIV-1 genotypes.
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http://dx.doi.org/10.1089/AID.2020.0190DOI Listing
February 2021

The Role of Exosomal Non-Coding RNAs in Coronary Artery Disease.

Front Pharmacol 2020 8;11:603104. Epub 2020 Dec 8.

Department of Cardiology, The Second Hospital of Jilin University, Changchun, China.

Cardiovascular disease (CVD) remains the leading cause of morbidity and mortality worldwide. Atherosclerosis (AS) is a major cause of CVD. Oxidative stress, endothelial dysfunction, and inflammation are key factors involved in the development and progression of AS. Exosomes are nano-sized vesicles secreted into the extracellular space by most types of cells, and are ideal substances for the transmission and integration of signals between cells. Cells can selectively encapsulate biologically active substances, such as lipids, proteins and RNA in exosomes and act through paracrine mechanisms. Non-coding RNAs (ncRNAs) are important for communication between cells. They can reach the recipient cells through exosomes, causing phenotypic changes and playing a molecular regulatory role in cell function. Elucidating their molecular mechanisms can help identify therapeutic targets or strategies for CVD. Coronary artery disease (CAD) is the most important disease in CVD. Here, we review the role and the regulatory mechanism of exosomal ncRNAs in the pathophysiology of CAD, as well as the potential contribution of exosomal ncRNA to diagnosis and treatment of CAD.
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http://dx.doi.org/10.3389/fphar.2020.603104DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7753098PMC
December 2020

Use of real-time sensors for compliance monitoring of nitrate in finished drinking water.

Water Sci Technol 2020 Dec;82(12):2725-2736

IIHR Hydroscience and Engineering, University of Iowa, Iowa City, IA, USA E-mail: University of Iowa Center for Health Effects of Environmental Contamination, Iowa City, IA, USA; Public Policy Center, University of Iowa, Iowa City, IA, USA; Department of Civil and Environmental Engineering, University of Iowa, 4105 Seamans Center for the Engineering Arts and Sciences, Iowa City, IA, USA.

Across the Midwestern United States, Public Water Systems (PWSs) struggle with high levels of nitrate in source waters from intense agricultural activity. Leveraging a sensor network deployed across Iowa surface waters, we evaluated the potential of the Hach Nitratax SC Plus, which uses UV-light absorption to quantify dissolved nitrate-nitrite (NO-N) down to 0.1 mg-N L, for real-time monitoring of NO-N in drinking water. For six different PWSs over multiple years, we compare NO-N levels in source waters (surface and groundwater under surface influence) to those measured via traditional methods (e.g., ion chromatography (IC)) for US EPA compliance monitoring. At one large PWS, we also evaluated sensor performance when applied to near-finished drinking water (filter effluent). We find good agreement between traditional analytical methods and in situ sensors. For example, for 771 filter effluent samples from 2006-2011, IC analysis averaged NO-N of 5.8 mg L while corresponding sensor measurements averaged 5.7 mg L with a mean absolute error of 0.23 (5.6%). We identify several benefits of using real-time sensors in PWSs, including improved frequency to capture elevated NO-N levels and as decision-support tools for NO-N management.
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http://dx.doi.org/10.2166/wst.2020.365DOI Listing
December 2020

Multichannel Saliency Detection Based on Visual Bionics.

Appl Bionics Biomech 2020 23;2020:8886923. Epub 2020 Nov 23.

College of Optoelectronics Science and Engineering, Soochow University, Suzhou Jiangsu Province 215000, China.

Inspired by the visual properties of the human eyes, the depth information of visual attention is integrated into the saliency detection to effectively solve problems such as low accuracy and poor stability under similar or complex background interference. Firstly, the improved SLIC algorithm was used to segment and cluster the RGBD image. Secondly, the depth saliency of the image region was obtained according to the anisotropic center-surround difference method. Then, the global feature saliency of RGB image was calculated according to the colour perception rule of human vision. The obtained multichannel saliency maps were weighted and fused based on information entropy to highlighting the target area and get the final detection results. The proposed method works within a complexity of O(N), and the experimental results show that our algorithm based on visual bionics effectively suppress the interference of similar or complex background and has high accuracy and stability.
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http://dx.doi.org/10.1155/2020/8886923DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7704193PMC
November 2020

Near Full-Length Genomic Characterization of 16 HIV-1 CRF01_AE Primary Isolates from Guangxi, China.

AIDS Res Hum Retroviruses 2021 Jan 25. Epub 2021 Jan 25.

Department of AIDS Research, State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China.

Isolation and culture of human immunodeficiency virus (HIV) are an important basis for acquired immune deficiency syndrome (AIDS) etiology, immunology, drug screening, clinical treatment, and vaccine research. CRF01_AE is one of the predominant strains of HIV-1 in China. However, there are few HIV-1 CRF01_AE isolates that have been reported. In this study, 16 HIV-1 CRF01_AE strains from Guangxi, China, were isolated, and the near full-length genomes were reverse transcribed and amplified in two halves with the 1 kb overlapping region. The polymerase chain reaction products were sequenced directly. The phylogenetic analysis results showed that all of the 16 isolated strains were CRF01_AE recombinant form, and two clusters were set up in the phylogenetic tree. The tropic prediction of 16 strains showed that 2 isolates were CCR5 tropic, and the others are CXCR4 tropic. Eight of the isolated strains are drug resistant according to the genetic prediction. These 16 near full-length characterized CRF01_AE isolates obtained in this study will provide valuable genomic and phenotypic information on HIV-1 strains circulating in China for related researches.
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http://dx.doi.org/10.1089/AID.2020.0277DOI Listing
January 2021

MicroRNA transcriptomic analysis of the sixth leaf of maize (Zea mays L.) revealed a regulatory mechanism of jointing stage heterosis.

BMC Plant Biol 2020 Nov 30;20(1):541. Epub 2020 Nov 30.

College of Agronomy, State Key Laboratory of Wheat and Maize Crop Science, Henan Agricultural University, #15 Longzi Lake University District, Zhengdong New District, Zhengzhou, 450046, Henan, People's Republic of China.

Background: Zhengdan 958 (Zheng 58 × Chang 7-2), a commercial hybrid that is produced in a large area in China, is the result of the successful use of the heterotic pattern of Reid × Tang-SPT. The jointing stage of maize is the key period from vegetative to reproductive growth, which determines development at later stages and heterosis to a certain degree. MicroRNAs (miRNAs) play vital roles in the regulation of plant development, but how they function in the sixth leaf at the six-leaf (V6) stage to influence jointing stage heterosis is still unclear.

Result: Our objective was to study miRNAs in four hybrid combinations developed in accordance with the Reid × Tang-SPT pattern, Zhengdan 958, Anyu 5 (Ye 478 × Chang 7-2), Ye 478 × Huangzaosi, Zheng 58 × Huangzaosi, and their parental inbred lines to explore the mechanism related to heterosis. A total of 234 miRNAs were identified in the sixth leaf at the V6 stage, and 85 miRNAs were differentially expressed between the hybrid combinations and their parental inbred lines. Most of the differentially expressed miRNAs were non-additively expressed, which indicates that miRNAs may participate in heterosis at the jointing stage. miR164, miR1432 and miR528 families were repressed in the four hybrid combinations, and some miRNAs, such as miR156, miR399, and miR395 families, exhibited different expression trends in different hybrid combinations, which may result in varying effects on the heterosis regulatory mechanism.

Conclusions: The potential targets of the identified miRNAs are related to photosynthesis, the response to plant hormones, and nutrient use. Different hybrid combinations employ different mature miRNAs of the same miRNA family and exhibit different expression trends that may result in enhanced or repressed gene expression to regulate heterosis. Taken together, our results reveal a miRNA-mediated network that plays a key role in jointing stage heterosis via posttranscriptional regulation.
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http://dx.doi.org/10.1186/s12870-020-02751-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7708177PMC
November 2020

Inference-Based Posteriori Parameter Distribution Optimization.

IEEE Trans Cybern 2020 Oct 7;PP. Epub 2020 Oct 7.

Encouraging the agent to explore has always been an important and challenging topic in the field of reinforcement learning (RL). Distributional representation for network parameters or value functions is usually an effective way to improve the exploration ability of the RL agent. However, directly changing the representation form of network parameters from fixed values to function distributions may cause algorithm instability and low learning inefficiency. Therefore, to accelerate and stabilize parameter distribution learning, a novel inference-based posteriori parameter distribution optimization (IPPDO) algorithm is proposed. From the perspective of solving the evidence lower bound of probability, we, respectively, design the objective functions for continuous-action and discrete-action tasks of parameter distribution optimization based on inference. In order to alleviate the overestimation of the value function, we use multiple neural networks to estimate value functions with Retrace, and the smaller estimate participates in the network parameter update; thus, the network parameter distribution can be learned. After that, we design a method used for sampling weight from network parameter distribution by adding an activation function to the standard deviation of parameter distribution, which achieves the adaptive adjustment between fixed values and distribution. Furthermore, this IPPDO is a deep RL (DRL) algorithm based on off-policy, which means that it can effectively improve data efficiency by using off-policy techniques such as experience replay. We compare IPPDO with other prevailing DRL algorithms on the OpenAI Gym and MuJoCo platforms. Experiments on both continuous-action and discrete-action tasks indicate that IPPDO can explore more in the action space, get higher rewards faster, and ensure algorithm stability.
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http://dx.doi.org/10.1109/TCYB.2020.3023127DOI Listing
October 2020

Blade-Type Reaction Front in Micrometer-Sized Germanium Particles during Lithiation.

ACS Appl Mater Interfaces 2020 Oct 8;12(42):47574-47579. Epub 2020 Oct 8.

Department of Mechanical and Energy Engineering, Indiana University Purdue University Indianapolis, Indianapolis, Indiana 46202, United States.

To investigate the lithium transport mechanism in micrometer-sized germanium (Ge) particles, in situ focused ion beam-scanning electron microscopy was used to monitor the structural evolution of individual Ge particles during lithiation. Our results show that there are two types of reaction fronts during lithiation, representing the differences of reactions on the surface and in bulk. The cross-sectional SEM images and transmission electron microscopy characterizations show that the interface between amorphous LiGe and Ge has a wedge shape because of the higher Li transport rate on the surface of the particle. The blade-type reaction front is formed at the interface of the amorphous LiGe and crystalline Ge and is attributed to the large strain at the interface.
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http://dx.doi.org/10.1021/acsami.0c13966DOI Listing
October 2020

Identification of a novel HIV-1 second-generation Circulating Recombinant Form CRF109_0107 in China.

J Infect 2020 11 16;81(5):816-846. Epub 2020 Sep 16.

Department of AIDS Research, State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, 20 Dongda Street, Fengtai District, Beijing 100071, China. Electronic address:

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http://dx.doi.org/10.1016/j.jinf.2020.09.007DOI Listing
November 2020

Dynamic alteration of dendrites and dendritic spines in the hippocampus and microglia in mouse brain tissues after kainate-induced status epilepticus.

Int J Neurosci 2020 Jun 1:1-13. Epub 2020 Jun 1.

Department of Neurology, Children's Hospital of Chongqing Medical University, Chongqing, China.

To study the alteration of microglial subtypes, the representative markers of microglia, and the morphology of dendrites and dendritic spines after acute status epilepticus (SE) and during recurrent seizures. A mouse kainate-induced SE model was used. Dendrites and dendritic spines of granule neurons in the dentate gyrus (DG) subregion and pyramidal neurons in the cornu ammonis (CA)1 and cornu ammonis (CA)3 subregions of the hippocampus were visualized by Golgi staining. Synaptic proteins were evaluated by Western blot analysis, and microglia and their markers were evaluated by flow cytometry. Extensive partial spine loss was observed in the dendrites of granule and pyramidal cells in the acute and early chronic stages of SE. In terms of spine loss, the thin and mushroom types predominated. Accompanying the spine loss in these two stages, the proportion of M1 microglia increased significantly with high CX3CR1 expression and low CD200R expression. However, at the transiting stage, the proportion of M2 microglia was increased dramatically, and high expression levels of CXCR3 on all microglia and CD68 on M1 microglia were observed. Morris water maze tests revealed significant learning and memory impairment in the chronic phase of epilepsy. Dendritic spines in the hippocampus and microglia in the central nevus system are dynamically altered in epilepsy during the establishment and maintenance of spontaneous seizures. Microglia may contribute to the spine loss and related learning and memory impairment.
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http://dx.doi.org/10.1080/00207454.2020.1770246DOI Listing
June 2020

Coevolution of Eukaryote-like Vps4 and ESCRT-III Subunits in the Asgard Archaea.

mBio 2020 05 19;11(3). Epub 2020 May 19.

Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, China

The emergence of the endomembrane system is a key step in the evolution of cellular complexity during eukaryogenesis. The endosomal sorting complex required for transport (ESCRT) machinery is essential and required for the endomembrane system functions in eukaryotic cells. Recently, genes encoding eukaryote-like ESCRT protein components have been identified in the genomes of Asgard archaea, a newly proposed archaeal superphylum that is thought to include the closest extant prokaryotic relatives of eukaryotes. However, structural and functional features of Asgard ESCRT remain uncharacterized. Here, we show that Vps4, Vps2/24/46, and Vps20/32/60, the core functional components of the Asgard ESCRT, coevolved eukaryote-like structural and functional features. Phylogenetic analysis shows that Asgard Vps4, Vps2/24/46, and Vps20/32/60 are closely related to their eukaryotic counterparts. Molecular dynamics simulation and biochemical assays indicate that Asgard Vps4 contains a eukaryote-like microtubule-interacting and transport (MIT) domain that binds the distinct type 1 MIT-interacting motif and type 2 MIT-interacting motif in Vps2/24/46 and Vps20/32/60, respectively. The Asgard Vps4 partly, but much more efficiently than homologs from other archaea, complements the null mutant of , further supporting the functional similarity between the membrane remodeling machineries of Asgard archaea and eukaryotes. Thus, this work provides evidence that the ESCRT complexes from Asgard archaea and eukaryotes are evolutionarily related and functionally similar. Thus, despite the apparent absence of endomembranes in Asgard archaea, the eukaryotic ESCRT seems to have been directly inherited from an Asgard ancestor, to become a key component of the emerging endomembrane system. The discovery of Asgard archaea has changed the existing ideas on the origins of eukaryotes. Researchers propose that eukaryotic cells evolved from Asgard archaea. This hypothesis partly stems from the presence of multiple eukaryotic signature proteins in Asgard archaea, including homologs of ESCRT proteins that are essential components of the endomembrane system in eukaryotes. However, structural and functional features of Asgard ESCRT remain unknown. Our study provides evidence that Asgard ESCRT is functionally comparable to the eukaryotic counterparts, suggesting that despite the apparent absence of endomembranes in archaea, eukaryotic ESCRT was inherited from an Asgard archaeal ancestor, alongside the emergence of endomembrane system during eukaryogenesis.
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http://dx.doi.org/10.1128/mBio.00417-20DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7240154PMC
May 2020

Safeguarding Female Reproductive Health against Endocrine Disrupting Chemicals-The FREIA Project.

Int J Mol Sci 2020 May 1;21(9). Epub 2020 May 1.

Department of Population Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 2, 3584 CM Utrecht, The Netherlands.

Currently available test methods are not well-suited for the identification of chemicals that disturb hormonal processes involved in female reproductive development and function. This renders women's reproductive health at increasing risk globally, which, coupled with increasing incidence rates of reproductive disorders, is of great concern. A woman's reproductive health is largely established during embryonic and fetal development and subsequently matures during puberty. The endocrine system influences development, maturation, and function of the female reproductive system, thereby making appropriate hormone levels imperative for correct functioning of reproductive processes. It is concerning that the effects of human-made chemicals on the endocrine system and female reproductive health are poorly addressed in regulatory chemical safety assessment, partly because adequate test methods are lacking. Our EU-funded project FREIA aims to address this need by increasing understanding of how endocrine disrupting chemicals (EDCs) can impact female reproductive health. We will use this information to provide better test methods that enable fit-for-purpose chemical regulation and then share our knowledge, promote a sustainable society, and improve the reproductive health of women globally.
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http://dx.doi.org/10.3390/ijms21093215DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7246859PMC
May 2020

Natural presence of the V179D and K103R/V179D mutations associated with resistance to nonnucleoside reverse transcriptase inhibitors in HIV-1 CRF65_cpx strains.

BMC Infect Dis 2020 Apr 28;20(1):313. Epub 2020 Apr 28.

Department of AIDS Research, State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, 100071, China.

Background: There is increasing evidence that HIV-1 genetic diversity can have an impact on drug resistance. The aim of this study is to investigate the epidemiological situation of CRF65_cpx and the impact of natural polymorphisms of this variant on genotypic resistance.

Methods: We used the BLAST search program followed by phylogenetic analysis to identify additional CRF65_cpx pol sequences from the Los Alamos HIV Sequence Database. Maximum likelihood phylogeny was estimated to clarify the epidemiological relationship of CRF65_cpx strains. Genotypic resistance was determined by submitting sequences to the Stanford HIV Drug Resistance Database.

Results: A total of 32 CRF65_cpx pol sequences were obtained. The CRF65_cpx strains were detected in seven provinces with large geographic distance. Yunnan CRF65_cpx sequences were mainly derived from a heterosexual risk group, whereas the CRF65_cpx sequences in other provinces were almost exclusively derived from an MSM population. With one exception of V179E, the other 31 strains harbored V179D mutation. The combination of V179D and K103R, conferring intermediate resistance to EFV and NVP, was detected in seven treatment-naive MSM patients.

Conclusions: This study confirmed the expansion CRF65_cpx in China. Furthermore, we found the natural presence of the V179D and K103R/V179D mutations associated with resistance to NNRTIs in HIV-1 CRF65_cpx. Our findings highlight the contribution of polymorphic mutations to drug resistance and underscore the challenges in treating patients harboring CRF65_cpx strains.
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http://dx.doi.org/10.1186/s12879-020-05007-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7189696PMC
April 2020

Role of Mitophagy in Cardiovascular Disease.

Aging Dis 2020 Apr 9;11(2):419-437. Epub 2020 Mar 9.

Department of Cardiology, The Second Hospital of Jilin University, Changchun 130041, China.

Cardiovascular disease is the leading cause of mortality worldwide, and mitochondrial dysfunction is the primary contributor to these disorders. Recent studies have elaborated on selective autophagy-mitophagy, which eliminates damaged and dysfunctional mitochondria, stabilizes mitochondrial structure and function, and maintains cell survival and growth. Numerous recent studies have reported that mitophagy plays an important role in the pathogenesis of various cardiovascular diseases. This review summarizes the mechanisms underlying mitophagy and advancements in studies on the role of mitophagy in cardiovascular disease.
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http://dx.doi.org/10.14336/AD.2019.0518DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069452PMC
April 2020

MicroRNA-103 Protects Coronary Artery Endothelial Cells against HO-Induced Oxidative Stress via BNIP3-Mediated End-Stage Autophagy and Antipyroptosis Pathways.

Oxid Med Cell Longev 2020 21;2020:8351342. Epub 2020 Feb 21.

Department of Cardiology, The Second Hospital of Jilin University, Changchun, Jilin, China.

Endothelial cell damage caused by oxidative stress is widely considered to be a triggering event in atherosclerosis (AS). However, the specific effect elicited by autophagy in endothelial cells undergoing oxidative stress remains controversial, especially during end-stage autophagy. The inhibition of end-stage autophagy has been reported to increase cell pyroptosis and contribute to endothelial damage. Several studies have shown that microRNA-103 is involved in end-stage autophagy; however, its specific mechanism of action is not yet characterized. In this study, we addressed the regulatory role of miR-103 in autophagy during oxidative stress of endothelial cells. Hydrogen peroxide (HO) treatment was used as an model of oxidative stress. MTS and ROS levels were measured to evaluate cell activity. qRT-PCR was used to detect the expression of miR-103. Autophagy was examined using western blot, immunofluorescence staining, and electron microscopy, while western blot analysis detected pyroptosis-related proteins. Results show that miR-103 expression decreased under oxidative stress. Further, miR-103 repressed transcription of Bcl-2/adenovirus E1B 19 kDa interacting protein (BNIP3). The oxidative stress caused by HO caused cell damage from 2 hours ( < 0.05) and increased the level of intracellular reactive oxygen species ( < 0.05); at the same time, the damage could be further aggravated by the stimulation of bafA1 ( < 0.05). Under the stimulation of HO, the expression of miR-103 decreased ( < 0.05). However, high expression of miR-103 could reduce the accumulation of LC3II and P62 ( < 0.05) by inhibiting the downstream target gene Bcl-2/adenovirus E1B 19 kDa interacting protein (BNIP3), thus reducing the occurrence of cell pyroptosis ( < 0.05). This process could be blocked by end-stage autophagy inhibitor bafA1 ( < 0.05), which further indicated that miR-103 affected cell injury by autophagy. On the contrary, the low expression of miR-103 promoted the accumulation of autophagy protein and increased the occurrence of pyroptosis ( < 0.05). In conclusion, inhibition of miR-103 restrained end-stage of autophagy by regulating BNIP3, thus changing the occurrence of cell pyroptosis.
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http://dx.doi.org/10.1155/2020/8351342DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7071805PMC
November 2020

Plasmonic Z-scheme Pt-Au/BiVO photocatalyst: Synergistic effect of crystal-facet engineering and selective loading of Pt-Au cocatalyst for improved photocatalytic performance.

J Colloid Interface Sci 2020 Jun 24;570:232-241. Epub 2020 Feb 24.

Department of Chemistry, School of Chemistry, Chemical Engineering and Life Sciences, Wuhan University of Technology, Wuhan 430070, PR China; State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, Wuhan 430070, PR China. Electronic address:

Constructing Z-scheme photocatalysts is one of the most effective technologies to enhance the photocatalytic reduction or oxidation ability in artificial photosynthesis. For the BiVO photocatalyst, it usually shows limited photocatalytic ability because of the severe bulk recombination of photogenerated carriers and the poor reduction reaction of photogenerated electrons. In this paper, a novel plasmonic Z-scheme Pt-Au/BiVO single-crystal photocatalyst was constructed to solve the above issues. Here, Au nanoparticles are selectively deposited on the electron-rich (0 1 0) facet of BiVO, while Pt nanoparticles are selectively modified on the Au surface. Photocatalytic results indicated that the resultant Pt-Au/BiVO Z-scheme photocatalyst exhibits an obviously higher photocatalytic performance than pure BiVO, Au/BiVO, randomly deposited BiVO(Pt-Au/BiVO(R)) and conventional Pt-Au/BiVO. More importantly, compared with the well-known Pt/BiVO(2.0 wt%), the Pt-Au/BiVO not only exhibits a higher photocatalytic performance, but also loads a lower amount of high-cost Pt cocatalyst. The excellent photocatalytic activity of the plasmonic Z-scheme Pt-Au/BiVO photocatalyst can be attributed to the synergistic effect of crystal-facet engineering and selective loading of Pt-Au, which results in the orientation transfer of photogenerated carriers in the single-crystal BiVO, the enhanced reduction power of photogenerated electrons, and the rapid oxygen-reduction reaction on Pt cocatalyst.
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http://dx.doi.org/10.1016/j.jcis.2020.02.093DOI Listing
June 2020

Greatly enhanced persistent luminescence of YPO:Sm phosphors via Tb incorporation for in vivo imaging.

Opt Express 2020 Jan;28(2):2649-2660

The premise that long afterglow can be applied is its duration, and the persistent duration is closely related to the depth of the traps. Therefore, the stable deep traps are the key to obtain long persistent luminescence. Based on this, a strategy that X-ray excites high-gap phosphors to achieve long persistent luminescence is firstly proposed. Herein, rare earth (RE) ions doped YPO phosphor is adopted as the research object as RE ions can form stable and deeper defect centers or luminescent centers in high bandgap materials. Furthermore, the efficient method of enhancing persistent luminescence is designed so that introducing Tb ions into YPO:Sm crystals forms tightly bound excitons, which modulates the depth of defect centers (Sm ions), improving the afterglow behavior from Sm ions for more than two days, which is approximately 14 times stronger than the afterglow of YPO:Sm phosphors itself. Finally, highly efficient in vivo deep tissue bioimaging was successfully achieved through mouse tail intravenous injection. The results indicate that the YPO:Sm,Tb phosphor possesses great promise in the field of in vivo imaging.
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http://dx.doi.org/10.1364/OE.384678DOI Listing
January 2020

Triple HIV-1 Infection Is Associated With Faster CD4 T-Cell Decline.

Front Microbiol 2020 24;11:21. Epub 2020 Jan 24.

Department of AIDS Research, State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China.

HIV-1 dual infection occurs when an individual is simultaneously or sequentially infected with two or more genetically distinct HIV-1 strains. According to the number of infected strains, HIV-1 dual infection can be divided in double infection and triple infection and so on. Currently, the majority of dual infection cases have been reported to be double infections which can result in detrimental clinical outcomes. The high incidence of double infection among specific high-risk populations increases the likelihood of triple infection, which has been sporadically described. There is no doubt that we are concerned about the association between triple infection and disease progression. However, this relationship is still unclear on the population level. In this study, 70 individuals from the Beijing PRIMO cohort were longitudinally followed up with a median time of 15.75 months for the purpose of investigating the incidence of dual infection. Phylogenetic analyses using bulk and single-genome sequences showed that nine individuals acquired double infection, with the incidence of 9.21 per 100 person-years, and three individuals with triple infection were identified, with the incidence of 3.07 per 100 person-years. The further survival analysis demonstrated that the triple infection group exhibited faster CD4 T-cell decline. In summary, these results demonstrate for the first time that the triple HIV-1 infection might reduce CD4 T-cell counts, which would predict a more rapid disease progression.
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http://dx.doi.org/10.3389/fmicb.2020.00021DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6992562PMC
January 2020

ZmIBH1-1 regulates plant architecture in maize.

J Exp Bot 2020 05;71(10):2943-2955

College of Agronomy, Synergetic Innovation Center of Henan Grain Crops and National Key Laboratory of Wheat and Maize Crop Science, Henan Agricultural University, Zhengdong New Area, Zhengzhou, Henan, China.

Leaf angle (LA) is a critical agronomic trait in maize, with more upright leaves allowing higher planting density, leading to more efficient light capture and higher yields. A few genes responsible for variation in LA have been identified by map-based cloning. In this study, we cloned maize ZmIBH1-1, which encodes a bHLH transcription factor with both a basic binding region and a helix-loop-helix domain, and the results of qRT-PCR showed that it is a negative regulator of LA. Histological analysis indicated that changes in LA were mainly caused by differential cell wall lignification and cell elongation in the ligular region. To determine the regulatory framework of ZmIBH1-1, we conducted RNA-seq and DNA affinity purification (DAP)-seq analyses. The combined results revealed 59 ZmIBH1-1-modulated target genes with annotations, and they were mainly related to the cell wall, cell development, and hormones. Based on the data, we propose a regulatory model for the control of plant architecture by ZmIBH1-1 in maize.
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http://dx.doi.org/10.1093/jxb/eraa052DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7260713PMC
May 2020

High prevalence and viremia of human pegivirus 2 in the HIV-infected population in Honghe Prefecture, Yunnan Province.

Arch Virol 2020 Mar 21;165(3):619-626. Epub 2020 Jan 21.

Department of AIDS Research, State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, 20 Dongda Street, Fengtai District, Beijing, 100071, China.

Human pegivirus 2 (HPgV-2) is a recently recognized pegivirus of the family Flaviviridae. To investigate the epidemic features of HPgV-2 circulating in the human immunodeficiency virus (HIV)-infected population, we tested for antibodies and viral RNA of HPgV-2 and hepatitis C virus (HCV) with retrospective plasma samples collected from 771 HIV infections with multiple risk behaviors in Honghe Prefecture of Yunnan Province. A total of 195 subjects (25.29%) were seroreactive to HPgV-2, and 41 (5.32%) were RNA positive. Although the positive rate of HPgV-2 antibodies in HIV/HCV-coinfected individuals (27.69%) was significantly higher than that of HIV monoinfections (20.82%) (p = 0.036), this is the first report of HPgV-2 viremia in HIV-infected individuals without HCV infection and the presence of two HPgV-2 lineages in China. Our data indicate that HPgV-2 can also be transmitted sexually, which might be facilitated when combined with HCV infection, injecting drug use, and risky sexual behavior, which appear to have a synergistic effect on HPgV-2 infection. Phylogenetic analysis of 26 near-full-length genome sequences showed that the HPgV-2 strains in China are divided into two clusters.
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http://dx.doi.org/10.1007/s00705-019-04512-6DOI Listing
March 2020

The Genetic Diversity of HIV-1 Quasispecies Within Primary Infected Individuals.

AIDS Res Hum Retroviruses 2020 05 6;36(5):440-449. Epub 2020 Jan 6.

Department of AIDS Research, State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China.

HIV has remarkable genetic diversity among populations. The diversity has critical impacts on transmission, immune escape, pathogenesis, and clinical management. HIV-1 diversity originates from frequent mutation and recombination during reverse transcription. This work focuses on the quasispecies genetic dynamics within individuals with primary infections. Eleven men who have sex with men from the Beijing PRIMO Clinical Cohort were identified as primary infection and had three or four series of their anticoagulant blood samples collected. Viral RNA was extracted and amplified using single-genome amplification. Products of the gene that met single-genome amplification requirements were sequenced. Subtype assortment of all collected sequences was performed using both the jumping profile hidden Markov model (jpHMM) and REGA. Quasispecies diversity at each time was estimated using Mega 6. Intrapatient recombination was analyzed using RDP4. According to the Fiebig classification system, YA-81 belongs to stage III and YA-113 belongs to stage IV. The other samples are all associated with the infection stage of V/VI. YA113 had a dual infection with subtype B and a new unique recombinant form involving CRF01_AE and C. The other eight were infected with CRF01_AE, one was infected with B/C recombinant, and the last one with B. Of the 10 single infections, 8 were caused by 1 founder virus. They all displayed a sharp increase of quasispecies diversity during the sampling times. Two were caused by at least two founder viruses. The diversity of these strains starts at a significantly high level and is followed by a relatively steady trend. Critically, the separate subtypes YA113-B and YA113-CRF01_AE/C both showed a similar trend to those infected by a single founder virus. Recombination analysis revealed that 5 of 11 cases underwent detectable intrapatient recombination. These findings indicate that tracing the dynamics of HIV-1 quasispecies during early infection may be relevant and valuable for understanding pathways of viral diversification and immune escape.
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http://dx.doi.org/10.1089/AID.2019.0242DOI Listing
May 2020

Natural presence of V179E and rising prevalence of E138G in HIV-1 reverse transcriptase in CRF55_01B viruses.

Infect Genet Evol 2020 01 31;77:104098. Epub 2019 Oct 31.

Department of AIDS Research, State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing 100071, China. Electronic address:

There is increasing evidence that naturally occurring HIV-1 genetic diversity can have an impact on drug resistance. Recently, our previous study has demonstrated the natural presence of the V179D and K103R/V179D mutations associated with resistance to nonnucleoside reverse transcriptase inhibitors (NNRTIs) in HIV-1 CRF65_cpx strains. The aim of this study is to investigate the presence of natural drug-resistance mutations (DRMs) in other HIV-1 subtypes or CRFs circulating in China. A total of 14,403 pol sequences from China were retrieved from the Los Alamos HIV Sequence Database, 10,041 of which were treatment naïve and presented substantial genetic diversity. Besides the natural presence of V179D and K103R/V179D in CRF65_cpx, the natural presence of V179E was found in CRF55_01B. In all but one of the 228 patients infected with CRF55_01B, NNRTI resistance mutation V179E was present and the combination of V179E and E138G was detected in 14 treatment-naïve patients, with a rate of 6.2%. A significant trend for increasing prevalence of E138G mutation in CRF55_01B strains over time was observed (p < .001). Phylogenetic analysis was conducted to clarify the epidemiological relationship of CRF55_01B strains. Most of the sequences containing E138G mutation scattered in the big CRF55_01B cluster, which indicated the rising prevalence of E138G was mainly due to multiple mutation events rather than local transmission clusters of a particular variant containing E138G mutation. Our findings highlight the importance of molecular surveillance of CRF55_01B strains and the urgent need for implementation of effective preventive measures to reduce the transmission of CRF55_01B.
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http://dx.doi.org/10.1016/j.meegid.2019.104098DOI Listing
January 2020