Publications by authors named "Wenqian Zhang"

103 Publications

Astrocyte-derived exosomes protect hippocampal neurons after traumatic brain injury by suppressing mitochondrial oxidative stress and apoptosis.

Aging (Albany NY) 2021 Sep 13;13(undefined). Epub 2021 Sep 13.

Department of Endocrinology, Tangshan Gongren Hospital, Tangshan, Hebei 063000, China.

In this study, we investigated the mechanisms through which astrocyte-derived exosomes (AS-Exos) alleviate traumatic brain injury (TBI)-induced neuronal defects in TBI model rats and mice. Treatment with AS-Exos alleviated neurobehavioral deficits, cognitive impairment, and brain edema in TBI rats. AS-Exos also significantly reduced neuronal cell loss and atrophy in the TBI rats. AS-Exos significantly reduced oxidative stress and mitochondrial HO levels by increasing the activity of antioxidant enzymes such as superoxide dismutase (SOD) and catalase (CAT) in the hippocampal neurons of TBI rats. TUNEL-staining assays showed that AS-Exos significantly reduced TBI-induced neuronal apoptosis. Mechanistically, AS-Exos ameliorated oxidative stress by activating Nrf2/HO-1 signaling in the hippocampus of TBI rats. In addition, the neuroprotective effects of AS-Exos were abrogated in brain-specific Nrf2-knockout mice subjected to TBI. These findings demonstrate that AS-Exos protects against TBI-induced oxidative stress and neuronal apoptosis by activating Nrf2 signaling in both rat and mouse models.
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http://dx.doi.org/10.18632/aging.203508DOI Listing
September 2021

A trail pheromone mediates the mutualism between ants and aphids.

Curr Biol 2021 Sep 2. Epub 2021 Sep 2.

College of Life Science, Institute of Life Science and Green Development, Hebei University, Baoding 071002, P.R. China; State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, P.R. China; Laboratory of Fundamental and Applied Research in Chemical Ecology (FARCE), University of Neuchâtel, 2000 Neuchâtel, Switzerland. Electronic address:

Mutualisms, such as the ones between ants and aphids, evolve and persist when benefits outweigh the costs from the interactions between the partners. We show here that the trail pheromone of the red imported fire ant, Solenopsis invicta, can enhance these benefits by suppressing aphid dispersal and stimulating their reproduction. The ant's mutualistic partner, the cotton aphid Aphis gossypii, was found to readily perceive and respond to two specific trail pheromone components. Two pheromone components, Z,E-α-farnesene and E,E-α-farnesene, both suppressed walking dispersal of apterous aphids, whereas only the major pheromone component, Z,E-α-farnesene, also increased aphid reproduction rate. The ants, as well as the aphids, benefit from this inter-species function of the trail pheromone. For the ants it increases and prolongs the availability of honeydew as a key food source, whereas the aphid colony benefits from faster population growth and continuous ant-provided protection. These findings reveal a hitherto unknown mechanism by which ants and aphids both increase the benefits that they provide to each other, thereby likely enhancing the stability of their mutualistic relationship.
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http://dx.doi.org/10.1016/j.cub.2021.08.032DOI Listing
September 2021

Three de novo variants in KMT2A (MLL) identified by whole exome sequencing in patients with Wiedemann-Steiner syndrome.

Mol Genet Genomic Med 2021 Sep 1:e1798. Epub 2021 Sep 1.

Precision Medical Laboratory, Wuhan Children's Hospital (Wuhan Maternal and Child Healthcare Hospital), Tongji Medical College, Huazhong University of Science & Technology, Wuhan, China.

Background: Wiedemann-Steiner syndrome (WSS) is an autosomal dominant disorder characterized by short stature, hypertrichosis, intellectual disability, developmental delay, along with facial dysmorphism. WSS patients exhibit great phenotypic heterogeneities. Some variants in KMT2A (MLL) gene have been identified as the cause of WSS.

Methods: Whole exome sequencing on the probands followed by Sanger sequencing validations in the family were applied to determine genetic variants. In silico analyses were used for predicting potential effects of the variants.

Results: We identified three novel de novo heterozygous variants: c.883A>T (p.Lys295*), c.4171C>T (p.Gln1391*), and c.3499T>C (p.Cys1167Arg), in KMT2A gene from three unrelated Chinese WSS patients. According to the American College of Medical Genetics and Genomics (ACMG) guidelines, these three variants were classified as pathogenic, pathogenic and likely pathogenic variant, respectively. By reviewing all the available cases with same mutated KMT2A regions as the three patients had, we found that in addition to the representative symptoms, our patients exhibited some sporadically observed symptoms, such as severe ophthalmological symptoms, endocardial fibroelastosis, cytomegalovirus infection, and feet eversion. We also revealed that variants in different KMT2A regions contribute to the phenotypic heterogeneity of WSS, highlighting challenges in the diagnosis of syndromic disorders spanning a broad phenotypic spectrum.

Conclusion: Our study would aid in further broadening our knowledge about the genotype-phenotype correlation of WSS.
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http://dx.doi.org/10.1002/mgg3.1798DOI Listing
September 2021

Antioxidant Therapy and Antioxidant-Related Bionanomaterials in Diabetic Wound Healing.

Front Bioeng Biotechnol 2021 24;9:707479. Epub 2021 Jun 24.

Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.

Ulcers are a lower-extremity complication of diabetes with high recurrence rates. Oxidative stress has been identified as a key factor in impaired diabetic wound healing. Hyperglycemia induces an accumulation of intracellular reactive oxygen species (ROS) and advanced glycation end products, activation of intracellular metabolic pathways, such as the polyol pathway, and PKC signaling leading to suppression of antioxidant enzymes and compounds. Excessive and uncontrolled oxidative stress impairs the function of cells involved in the wound healing process, resulting in chronic non-healing wounds. Given the central role of oxidative stress in the pathology of diabetic ulcers, we performed a comprehensive review on the mechanism of oxidative stress in diabetic wound healing, focusing on the progress of antioxidant therapeutics. We summarize the antioxidant therapies proposed in the past 5 years for use in diabetic wound healing, including Nrf2- and NFκB-pathway-related antioxidant therapy, vitamins, enzymes, hormones, medicinal plants, and biological materials.
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http://dx.doi.org/10.3389/fbioe.2021.707479DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8264455PMC
June 2021

Comparative observation of atmospheric nitrous acid (HONO) in Xi'an and Xianyang located in the GuanZhong basin of western China.

Environ Pollut 2021 Jul 5;289:117679. Epub 2021 Jul 5.

State Key Laboratory for Structural Chemistry of Unstable and Stable Species Beijing National Laboratory for Molecular Sciences (BNLMS), CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing, China; Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, PR China; University of Chinese Academy of Sciences, Beijing, China.

HONO is an important component of reactive nitrogen (N) and precursors of OH radical. However, the source and removal of HONO are not clear. Here, measurements of HONO (May 18-31, 2018) were conducted in Xi'an and Xianyang simultaneously for the first time. The relationship between HONO and other N (such as NO and NO) in two cities was analyzed. The mixing ratio of HONO in Xi'an was 1.2 ± 0.8 ppbv, and that in Xianyang was 1.2 ± 1.1 ppbv. The nighttime HONO mixing ratio was higher in Xianyang, while the daytime HONO was higher in Xi'an. Compared with the contribution from heterogeneous process of NO, direct emissions and homogeneous processes (NO + OH) were less important for nocturnal HONO formation in these two cities. The relative contribution of heterogeneous process in Xianyang was more important than that in Xi'an. The reaction of NO upon aerosols surface was identified as an important source of HONO for two sites. The conversion of NO on the other surfaces might attend the heterogeneous formation of HONO in Xianyang site. Daytime HONO budget analysis indicated that there was an additional unknown formation process of HONO at two sites. The net OH production rate from HONO (from 08:00 to 17:00) was 1.6 × 10 and 1.3 × 10 molecule/(cm s) for Xian and Xianyang, 5.2 and 3.5 times higher than from O photolysis. Besides, a dust storm appeared during this observation period, and the impact of local emission and transport processes was separately analyzed. The sources, characteristics, and effects of HONO identified in this study laid a foundation for further research on HONO and air pollution in the Guanzhong area.
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http://dx.doi.org/10.1016/j.envpol.2021.117679DOI Listing
July 2021

Rapid Body-Wide Transcriptomic Turnover During Rhesus Macaque Perinatal Development.

Front Physiol 2021 10;12:690540. Epub 2021 Jun 10.

School of Life Sciences, Guizhou Normal University, Guiyang, China.

An hourglass cup-shape pattern of regulation at the molecular level was detected during the development of the primate brain. Specifically, a peak of temporally differentially expressed genes around the time of birth has been observed in the human brain. However, to what extend this peak of regulation exists among species has not been investigated in great detail. Here, by integrating multiple large-scale transcriptome data from rhesus macaques, we confirmed that a similar differential expression peak exists during the development of the macaque brain. We also found that a similar peak exists during the development of other organs, such as liver, testis, kidney and heart. Furthermore, we found that distinct pathways are regulated in the peak period of those organs. Our results highlight the importance of co-evolution of diverse organs during critical periods of perinatal development in primates.
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http://dx.doi.org/10.3389/fphys.2021.690540DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8223001PMC
June 2021

High glucose exacerbates neuroinflammation and apoptosis at the intermediate stage after post-traumatic brain injury.

Aging (Albany NY) 2021 06 27;13(12):16088-16104. Epub 2021 Jun 27.

Department of Endocrinology, Tangshan Gongren Hospital, Tangshan, Hebei 063000, China.

Traumatic brain injury (TBI) is a highly lethal event with a poor prognosis. Recovering residual neuronal function in the intermediate stage of TBI is important for treatment; however, neuroinflammation and neuronal apoptosis impede residual neuronal repair processes. Considering that hyperglycemia influences inflammatory processes and neuronal survival, we examined the effects of high glucose on neuroinflammation and neuronal death during the intermediate phase of TBI. Rat models of type 2 diabetes mellitus and/or TBI were developed and behaviorally assessed. Neurological function and cognitive abilities were impaired in TBI rats and worsened by type 2 diabetes mellitus. Histopathological staining and analyses of serum and hippocampal mRNA and protein levels indicated that neuroinflammation and apoptosis were induced in TBI rats and exacerbated by hyperglycemia. Hyperglycemia inhibited hippocampal mitogen-activated protein kinase kinase 5 (MEK5) phosphorylation in TBI rats. assays were used to assess inflammatory factor expression, apoptotic protein levels and neuronal survival after MEK5 activation in TBI- and/or high-glucose-treated neurons. MEK5/extracellular signal-regulated kinase 5 (ERK5) pathway activation reduced the inflammation, cleaved caspase-3 expression, Bax/Bcl-2 ratio and apoptosis of TBI neurons, even under high-glucose conditions. Thus, high glucose exacerbated neuroinflammation and apoptosis in the intermediate stage post-TBI by inhibiting the MEK5/ERK5 pathway.
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http://dx.doi.org/10.18632/aging.203136DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8266309PMC
June 2021

Outcomes of long versus short stent cronus hybrid prosthesis in type A aortic dissection: A single centre experience.

J Card Surg 2021 Sep 23;36(9):3261-3268. Epub 2021 Jun 23.

Department of Cardiovascular Surgery, Guangdong Provincial Hospital of Chinese Medicine, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, China.

Objectives: The frozen elephant trunk (FET) technique has become an important tool in the treatment of acute type A aortic dissection. The aim of this study was to evaluate the effect of long FET on spinal cord injury (SCI) and distal aortic remodeling after acute type A aortic dissection based on clinical and radiological outcomes.

Methods: From January 2018 to November 2019, 158 patients (mean age 51.8 years [range: 32-78 years], 88.6% male) with acute type A aortic dissection were treated by FET with 100 mm (n = 113) or 150 mm (n = 45) open hybrid stent graft prosthesis. Patients were divided into two groups according to the length of FET. The clinical and radiological outcomes of the patients were reviewed retrospectively.

Results: Postoperative outcomes did not differ significantly: in-hospital mortality (9.7% vs. 6.7%, p = .758) and SCI (5.3% vs. 2.2%, p = .674). Aortic remodeling, which was evaluated by aortic diameter, true lumen diameter, false lumen (FL) diameter and the rate of FL complete thrombosis, was more positive in long FET group in the descending thoracic aorta during the follow-up period. At the abdominal level, there was no statistically significant difference between the two groups.

Conclusions: The long version of FET does not increase the risk of SCI in patients with acute type A aortic dissection. The application of long FET can achieve better results in terms of remodeling of the thoracic aorta in the short- and medium-term follow-up.
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http://dx.doi.org/10.1111/jocs.15766DOI Listing
September 2021

The efficacy of intravenous vitamin C in critically ill patients: A meta-analysis of randomized controlled trials.

Clin Nutr 2021 05 24;40(5):2630-2639. Epub 2021 Mar 24.

Department of Cardiology, The Second Affiliated Hospital, Xi'an Jiaotong University, Xi'an, Shaanxi, PR China. Electronic address:

Background & Aims: A large number of clinical studies have shown that intravenous vitamin C supplementation is beneficial for critically ill patients, but current research conclusions are controversial. This meta-analysis included high-quality randomized controlled trials (RCTs) to evaluate the efficacy of intravenous vitamin C in critically ill patients.

Methods: We searched PubMed, EMBASE and the Cochrane Library from inception to August 15, 2020 to identify published reports of RCTs evaluating the role of intravenous vitamin C in critically ill patients. Risk ratios values (RRs) and 95% confidence intervals (CIs) were calculated by random-effects meta-analysis. Trial sequential analysis (TSA), meta-regression, subgroup analyses and sensitivity analyses were also performed.

Results: Our meta-analysis included 18 RCTs involving 2001 patients (1005 with vitamin C treatment and 996 control treatment). Intravenous vitamin C administration reduced the intensive care unit (ICU) length of stay (LOS) (MD = -0.36, 95% CI: -0.60 to -0.11, P = 0.004) and hospital LOS (MD = -1.50, 95% CI: -2.64 to -0.35, P = 0.01) but had no significant effect on the longest follow-up mortality, hospital or ICU mortality and change in Sequential Organ Failure Assessment (SOFA) score. TSAs for mortality, ICU and hospital LOS were inconclusive.

Conclusions: Intravenous vitamin C administration may shorten ICU LOS and hospital LOS. It had no effect on mortality and organ failure. All TSAs were inconclusive, and the value of vitamin C for critically ill patients needs to be demonstrated in more high-quality RCTs.
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http://dx.doi.org/10.1016/j.clnu.2021.03.007DOI Listing
May 2021

Biochar Improves Soil-Tomato Plant, Tomato Production, and Economic Benefits under Reduced Nitrogen Application in Northwestern China.

Plants (Basel) 2021 Apr 13;10(4). Epub 2021 Apr 13.

College of Water Resources and Architectural Engineering, Northwest A&F University, Weihui Road 23, Yangling 712100, China.

The tomato is an important economic crop that is a main ingredient of some prepared food as well as a focus of the agricultural industry. Optimizing nitrogen (N) fertilizers is essential for sustainable agricultural development, while the excessive use of N fertilizers leads to environmental and food production problems. As a soil amendment, biochar has been widely used to improve soil quality and crop yield. However, little information is available on the effects of biochar and N fertilizer reduction on tomato plant, soil characteristics in tomato cultivation and tomato production. In this study, a greenhouse experiment was carried out in Yangling, Shaanxi province, China, including four biochar levels (0, 30, 50, and 70 t ha) under drip irrigation and four N application rates (170, 190, 210, and 250 kg ha). The results showed that adding too much biochar (e.g., 70 t ha) and reducing N fertilizer too far (e.g., by 32%) will not lead to satisfactory results in terms of tomato growth, tomato yield and quality, and economic benefits. Biochar addition could significantly enhance microbial abundance, enzyme activity, and tomato growth compared with non‒biochar treatments when reducing the amount of applied N fertilizer by 16% or 24% (N2 and N3). From the perspectives of tomato yield, tomato quality (sugar‒acid ratio and vitamin C (VC) content), and economic benefits, optimal application rate of biochar and N fertilizer based on the silty clay loam soil of northwest China under drip irrigation is proposed, respectively. The proposal is based on both multidimensional nonlinear regression models and a comparison with experimental treatments. For example, biochar addition at 50 t ha and reducing N fertilizer by 24% achieved the greatest tomato yield. Compared with non-biochar treatment under the corresponding N fertilizer level, soil enzyme activity (urease, phosphatase, and catalase), microbial abundance (bacteria, fungi, and actinomycetes), leaf gas exchange parameters (gs, Pn, and Tr), and biomass increased on average by 88.76%, 7.49%, 43.23%, and 39.67%, respectively. Based on a comprehensive consideration of tomato yield, VC content, sugar‒acid ratio, and economic benefits, 35 t ha biochar and 200 kg ha N fertilizer is the recommended combination of biochar and nitrogen fertilizer for local farmers.
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http://dx.doi.org/10.3390/plants10040759DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8070344PMC
April 2021

Nitrogen-Doped Multiwalled Carbon Nanotubes Enhance Bone Remodeling through Immunomodulatory Functions.

ACS Appl Mater Interfaces 2021 Jun 28;13(21):25290-25305. Epub 2021 Apr 28.

College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Tai'an 271018, China.

It has been reported that multiwalled carbon nanotubes (MWCNTs) can reportedly positively affect growth and differentiation of bone-related cells and therefore offer great potential in biomedical applications. To overcome negative immune responses that limit their application, specific doping and functionalization can improve their biocompatibility. Here, we demonstrated that nitrogen-doped carboxylate-functionalized MWCNTs (N-MWCNTs) enhance bone remodeling both and with excellent biocompatibility, via stimulation of both bone resorption and formation. We revealed that 0.2 μg/mL N-MWCNTs not only increase the transcription of osteoblastogenic and osteoclastogenic genes but also up-regulate the activities of both TRAP and AKP in the differentiation of bone marrow stromal cells (BMSCs). Additionally, intramuscular administration of N-MWCNTs at a dosage of 1.0 mg/kg body weight enhances bone mineral density and bone mass content in mice, as well as induces potentiated degree of TRAP- and ARS-positive staining in the femur. The positive regulation of N-MWCNTs on bone remodeling is initiated by macrophage phagocytosis, which induces altered production of inflammatory cytokines by immune response pathways, and consequently up-regulates IL1α, IL10, and IL16. These cytokines collectively regulate the central osteoclastogenic transcription factor NFATc1 and osteoblastogenic BMP signaling, the suppression of which confirmed that these factors respectively participate in N-MWCNT-mediated regulation of osteoclastic and osteoblastic bone marrow stem cell activities. These results suggest that N-MWCNTs can be readily generalized for use as biomaterials in bone tissue engineering for metabolic bone disorders.
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http://dx.doi.org/10.1021/acsami.1c05437DOI Listing
June 2021

Safety and Efficacy of Transcatheter Occlusion of Perimembranous Ventricular Septal Defect with Aortic Valve Prolapse: A Six-Year Follow-Up Study.

J Interv Cardiol 2021 18;2021:6634667. Epub 2021 Mar 18.

Graduate School, The Second School of Clinical Medicine, Southern Medical University, Guangzhou, China.

Background: With the rapid development of transcatheter techniques and instruments, transcatheter occlusion for patients with perimembranous ventricular septal defect (pVSD) and aortic valve prolapse (AVP) was constantly being tried, while the efficacy and safety of pVSD with AVP remain controversial.

Objective: The aim of this study was to evaluate long-term efficacy and safety of transcatheter occlusion of pVSD with AVP.

Methods: We retrospectively analyzed 164 children with pVSD and AVP who underwent transcatheter occlusion between January 2013 and November 2014. AVP was divided into 3 degrees according to right coronary leaflet morphology at end-diastole during aortic root angiography. Patient demographic and clinical data were collected.

Results: There were 97 males and 67 females (median age, 40.0 (30.0-62.7) months; average weight, 16.94 ± 9.02 kg). Mild ( = 63), moderate ( = 89), and severe ( = 12) AVP success rates were 93.7%, 89.9%, and 58.3%, respectively. Immediately after procedure, there was no new-onset aortic regurgitation (AR) above trivial degree, residual shunt above mild degree, or complications requiring medication or operation, except for 1 patient who developed transient complete atrioventricular block. During follow-up, 1 mild AVP patient aggravated from mild to moderate AR and 1 moderate AVP patient aggravated from trivial to moderate AR. The new-onset AR in mild, moderate, and severe AVP was 2%, 1.8%, and 20%, respectively. AR disappeared in 17 patients. Residual shunt occurred in 9 patients after procedure, 4 of which disappeared during the follow-up period. No serious complications occurred in any patient during follow-up. Five-year cardiovascular event-free survival rates for mild, moderate, and severe AVP were 89.6%, 94.5%, and 80.0%, respectively.

Conclusion: Transcatheter occlusion of pVSD with mild and moderate AVP has a high success rate and few complications, which is safe and effective in long-term follow-up. Transcatheter occlusion of pVSD with severe AVP has low success rates and high AR incidence. Therefore, transcatheter occlusion of pVSD with AVP is recommended for mild to moderate, but not severe, AVP.
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http://dx.doi.org/10.1155/2021/6634667DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7997740PMC
June 2021

Experimental study for the establishment of a chemotherapy-induced ovarian insufficiency model in rats by using cyclophosphamide combined with busulfan.

Regul Toxicol Pharmacol 2021 Jun 9;122:104915. Epub 2021 Mar 9.

Department of Gynecology and Obstetics, The Second Affiliated Hospital, Chongqing MedicalUniversity, Chongqing, 400010, People's Republic of China. Electronic address:

With an improvement in the survival rate of cancer patients, chemotherapy-induced premature ovarian insufficiency (POI) is increasingly affecting the quality of life of female patients. Currently, there are many relevant studies using mice as an animal model. However, a large coefficient of variation for weight in mice is not appropriate for endocrine-related studies, compared with rats; therefore, it is necessary to identify an appropriate experimental model in rats. In this study, cyclophosphamide combined with busulfan was used to establish an animal model. We compared several common modeling methods using chemotherapeutic drugs, cisplatin, cyclophosphamide, and 4-vinylcyclohexene diepoxide (VCD), and we found that the combination of cyclophosphamide and busulfan was more effective in establishing a POI model in rats with few side effects by analyzing general physical conditions, pathological tissue sections of heart, liver, lung, spleen, kidney, uterus, and ovary, serum hormone levels, and follicle counts; thus, providing a more reliable model basis for subsequent studies.
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http://dx.doi.org/10.1016/j.yrtph.2021.104915DOI Listing
June 2021

Important Oxidants and Their Impact on the Environmental Effects of Aerosols.

J Phys Chem A 2021 May 9;125(18):3813-3825. Epub 2021 Mar 9.

State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Beijing National Laboratory for Molecular Sciences (BNLMS), CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China.

Oxidants are central species in the atmosphere, where they not only determine secondary particle formation but also impact human health and climate change. In general, they are unstable, highly reactive, and recyclable and have been studied in field observations, laboratory studies, and model simulations. The most widely investigated oxidants, such as OH radicals, O, and Cl atom, HONO, NO, NO, and Criegee Intermediates (CIs) have attracted more attention recently. Furthermore, secondary particles formed in the oxidations processes impact the particle physicochemical properties, such as hygroscopicity and optical properties and therefore impact the atmospheric radiation balance. Therefore, the newest investigation results of important oxidants (HONO, NO, NO, and CIs) are reviewed in this manuscript, and the environmental effects of secondary particles formed through corresponding oxidation processes are also stated. Furthermore, some perspectives are further discussed in the article.
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http://dx.doi.org/10.1021/acs.jpca.0c10236DOI Listing
May 2021

Aerosol Promotes Peroxyacetyl Nitrate Formation During Winter in the North China Plain.

Environ Sci Technol 2021 03 3;55(6):3568-3581. Epub 2021 Mar 3.

State Key Laboratory of Severe Weather & Key Laboratory for Atmospheric Chemistry of CMA, Institute of Atmospheric Composition, Chinese Academy of Meteorological Sciences, Beijing 100081, China.

Peroxyacetyl nitrate (PAN) is an important indicator for photochemical pollution, formed similar to ozone in the photochemistry of certain volatile organic compounds (VOCs) in the presence of nitrogen oxides, and has displayed surprisingly high concentrations during wintertime that were better correlated to particulate rather than ozone concentrations, for which the reasons remained unknown. In this study, wintertime observations of PAN, VOCs, PM, HONO, and various trace gases were investigated to find the relationship between aerosols and wintertime PAN formation. Wintertime photochemical pollution was affirmed by the high PAN concentrations (average: 1.2 ± 1.1 ppb, maximum: 7.1 ppb), despite low ozone concentrations. PAN concentrations were determined by its oxygenated VOC (OVOC) precursor concentrations and the NO/NO ratios and can be well parameterized based on the understanding of their chemical relationship. Data analysis and box modeling results suggest that PAN formation was mostly contributed by VOC aging processes involving OH oxidation or photolysis rather than ozonolysis pathways. Heterogeneous reactions on aerosols have supplied key photochemical oxidants such as HONO, which produced OH radicals upon photolysis, promoting OVOC formation and thereby enhancing PAN production, explaining the observed PM-OVOC-PAN intercorrelation. In turn, parts of these OVOCs might participate in the formation of secondary organic aerosol, further aggravating haze pollution as a feedback. Low wintertime temperatures enable the long-range transport of PAN to downwind regions, and how that will impact their oxidation capacity and photochemical pollution requires further assessment in future studies.
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http://dx.doi.org/10.1021/acs.est.0c08157DOI Listing
March 2021

An aorto-oesophageal fistula treated with total arch repair combined with oesophageal repair.

Interact Cardiovasc Thorac Surg 2021 Jun;33(1):145-147

Department of Cardiovascular Surgery, Guangdong Provincial Hospital of Chinese Medicine, the Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China.

Aorto-oesophageal fistula is a rare but fatal disease. Open surgical repair or endotube repair of aorta and oesophagus save patients from circulatory deterioration, major haematemesis and severe infection. Here we present a rare case of an aorto-oesophageal fistula in the right hemi-arch caused by a fish bone treated with an alternative surgical strategy. Total aortic arch repair using the frozen elephant trunk procedure combined with oesophageal repair were performed. No aortic fistula, oesophageal fistula or artificial graft infection occurred in the follow-up.
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http://dx.doi.org/10.1093/icvts/ivab038DOI Listing
June 2021

Facile preparation of novel nickel sulfide modified KNbO heterojunction composite and its enhanced performance in photocatalytic nitrogen fixation.

J Colloid Interface Sci 2021 May 1;590:548-560. Epub 2021 Feb 1.

Department of Materials Science and Engineering, Zhejiang Normal University, Jinhua 321004, China; Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, Institute of Physical Chemistry, Zhejiang Normal University, Jinhua 321004, China. Electronic address:

This work was designed to prepare a novel NiS/KNbO p-n heterojunction composite for efficient photocatalytic nitrogen fixation under simulated sunlight. The NiS/KNbO photocatalyst was prepared through a two-step hydrothermal method. X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy analyses proved that NiS nanoparticles were closely decorated on the surface of KNbO nanorods, to facilitate the migration of electrons between the two semiconductors. Mott-Schottky analysis indicated that the Femi level of KNbO is higher than that of NiS. Thus, the electron migration from KNbO to NiS occurs naturally. This migration elevates the band potential of NiS, makes NiS/KNbO form a type-II photocatalyst, and generates an internal electric field in the composite. The synergetic effect of the internal electric field and the type-II band structure endows NiS/KNbO with high efficiency in the spatial separation of photogenerated electron-hole pairs, verified by electrochemical impedance spectroscopy and transient photocurrent experiments. Therefore, NiS/KNbO presents good efficiency in photocatalytic N reduction with an NH production rate of 155.6 μmol·L·g·h, which is 1.9 and 6.8 times higher than those of KNbO and NiS, respectively. UV-visible diffuse reflectance spectroscopy and N-adsorption experiments were also performed to investigate the effect of light absorption and surface area on the photocatalytic reaction. Nevertheless, compared with the great promotion effect in charge separation, the contribution of the two factors can be ignored.
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http://dx.doi.org/10.1016/j.jcis.2021.01.086DOI Listing
May 2021

Effects of exogenous adiponectin supplementation in early pregnant PCOS mice on the metabolic syndrome of adult female offspring.

J Ovarian Res 2021 Jan 18;14(1):15. Epub 2021 Jan 18.

Department of Reproductive Medicine, The First Affiliated Hospital, Jinan University, 601 West Huangpu Avenue, 510000, Guangzhou, People's Republic of China.

Objective: PCOS is a heterogeneous endocrine disorder with both reproductive and metabolic abnormalities. At present, PCOS has been confirmed to have a certain genetic background. Compared with healthy women, the vast majority of PCOS patients have hyperandrogenemia, and this excessive androgen exposure during pregnancy may affect the development of female fetuses. The aim of the current study was to investigate the effect of adiponectin intervention during early pregnancy of obese mice with PCOS on the metabolic phenotype of adult female offspring.

Methods: After the PCOS model was established, C57BL/6J mice were divided into maternal-control, maternal-PCOS, and maternal-PCOS + APN groups. DHEA-induced PCOS mice were supplemented with adiponectin (10 mg/kg/day) in the early pregnancy in order to eliminate adverse hormone exposure and then traced for endocrine indicators in their adult female offspring, which were observed for metabolism syndrome or endocrine disturbance and exhibited the main effects of APN. To further explore the underlying mechanism, the relative expressions of phosphorylated AMPK, PI3K, and Akt were detected in the ovaries of offspring mice.

Results: The serum testosterone level of the maternal-PCOS + APN group in early pregnancy was significantly lower than that of the maternal-PCOS group (p < 0.01). The serum testosterone level in the offspring-PCOS + APN group was significantly lower than in the offspring-PCOS group (p <0.05), the diestrus time characterized by massive granulocyte aggregation in the estrus cycle was significantly shorter than in the offspring-PCOS group (p<0.05), and the phenotypes of PCOS-like reproductive disorders and metabolic disorders, such as obesity, insulin resistance, impaired glucose tolerance, and hyperlipidemia, were also significantly improved in the offspring-PCOS + APN group (p < 0.05). Compared with the control group, the expression levels of phosphorylated AMPK, PI3K, and Akt in the offspring-PCOS group were significantly decreased (p < 0.05), while those in the offspring-PCOS + APN group were significantly increased (p < 0.05).

Conclusions: APN intervention in early pregnancy significantly reduced the adverse effects of maternal obesity and high androgen levels during pregnancy on female offspring and corrected the PCOS-like endocrine phenotype and metabolic disorders of adult female offspring. This effect may be caused by the activation of the AMPK/PI3K-Akt signaling pathway in PCOS offspring mice.
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http://dx.doi.org/10.1186/s13048-020-00755-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7812650PMC
January 2021

Talbot effect in arrays of helical waveguides.

Opt Lett 2021 Jan;46(2):322-325

We demonstrate that periodic self-imaging of light patterns with certain input periods can be effectively realized in one-dimensional and two-dimensional helical waveguide arrays. The band structure is drastically dependent on the helix radius and period, and the complete collapse of quasi-energy bands occurs for a certain helix radius and period, which strongly affects the intensity carpet and the Talbot length of the Talbot self-imaging effect. Talbot length would extend to infinity, as the helix radius and period approach the corresponding critical values corresponding to the band collapse, where the inversion of intensity distribution between even and odd waveguides is observed for the binary input pattern with /2 phase shift between the adjacent waveguides.
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http://dx.doi.org/10.1364/OL.415326DOI Listing
January 2021

The antagonistic effects and mechanisms of microRNA-26a action in hypertensive vascular remodelling.

Br J Pharmacol 2021 03 28;178(5):1037-1054. Epub 2021 Jan 28.

Department of Cardiology, The Second Affiliated Hospital, Xi'an Jiaotong University, Xi'an, P.R. China.

Background And Purpose: Hypertensive vascular remodelling is responsible for end-organ damage and is the result of increased extracellular matrix accumulation and excessive vascular smooth muscle cell (VSMC) proliferation. MicroRNA-26a (miR-26a), a non-coding small RNA, is involved in several cardiovascular diseases. We aimed to validate the effect and mechanisms of miR-26a in hypertensive vascular remodelling.

Experimental Approach: Male spontaneously hypertensive rats (SHRs) were injected intravenously with recombinant adeno-associated virus-miR-26a. Samples of thoracic aorta were examined histologically with H&E staining. In vitro, angiotensin II (AngII)-induced VSMCs cultured from thoracic aortae of female Sprague-Dawley rats, were transfected with miR-26a mimic or inhibitor. Western blots, qRT-PCR and immunohistological methods were used, along with chromatin-immunoprecipitation and luciferase reporter assays. Specific siRNAs were used to silence Smad production in VSMCs KEY RESULTS: Levels of miR-26a were lower in the thoracic aorta and plasma of SHRs than in WKY rats. Overexpression of miR-26a inhibited extracellular matrix deposition by targeting connective tissue growth factor (CTGF) and decreased VSMC proliferation by regulating the enhancer of zeste homologue 2 (EZH2)/p21 pathway both in vitro and in vivo. AngII-mediated Smad3 activation suppressed miR-26a expression, which in turn promoted Smad3 activation via targeted regulation of Smad4, leading to further down-regulation of miR-26a.

Conclusion And Implications: Our data show that AngII stimulated a Smads/miR-26a positive feedback loop, which further reduced expression of miR-26a, leading to collagen production and VSMC proliferation and consequently vascular remodelling. MiR-26a has an antagonistic effect on hypertensive vascular remodelling and can be a strategy for treating hypertensive vascular remodelling.
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http://dx.doi.org/10.1111/bph.15337DOI Listing
March 2021

HMGB-1/RAGE signaling inhibition by dioscin attenuates hippocampal neuron damage induced by oxygen-glucose deprivation/reperfusion.

Exp Ther Med 2020 Dec 15;20(6):231. Epub 2020 Oct 15.

Department of Neurosurgery, Tangshan Gongren Hospital, Tangshan, Hebei 063000, P.R. China.

Cerebral ischemia is one of the most common clinical diseases characterized by high morbidity and mortality. Neurocyte apoptosis and a cascade of inflammatory signals following cerebral ischemia-reperfusion injury (IRI) may contribute to secondary brain damage, resulting in severe neurological damage. It has been reported that dioscin, a natural steroid saponin, exerts anti-inflammatory properties against different diseases. The present study aimed to investigate the role of dioscin in oxygen-glucose deprivation/reperfusion (OGD/R) induction in hippocampal cells and . For the study, hippocampal cells were collected from rat embryos of gestational age of E18. The oxygen-glucose deprivation model in primary hippocampal neurons was used to mimic cerebral IRI . To select the optimum dioscin concentration and acting time, cell viability was evaluated by a Cell Counting Kit-8 (CCK-8) assay. Neurons subjected to OGD/R were treated with dioscin and the inflammatory cytokines, high mobility group box chromosomal protein 1 (HMGB-1)/receptor for advanced glycation end products (RAGE) signaling molecules and apoptosis-associated genes were determined. The intracellular reactive oxygen species (ROS) generation was detected. Furthermore, the effects of dioscin on the antioxidant defense mechanisms were evaluated by measuring the activity of glutathione peroxidase (GPx), superoxide dismutase (SOD), catalase (CAT) and the glutathione (GSH)/glutathione disulphide (GSSG) ratio. In addition, OGD/R-induced cells were transfected with pcDNA3.1-HMGB-1 and treated with dioscin, and the neuronal cell apoptosis rate was determined using a terminal deoxynucleotidyl transferase-mediated 2-deoxyuridine 5-triphosphate-biotin nick-end labeling (TUNEL) assay. The mRNA and protein expression levels of the inflammatory factors were measured using real-time quantitative polymerase chain reaction (RT-qPCR) and western blot analysis, respectively. For the investigation, the oxidation and anti-oxidation system in rat hippocampal tissue was evaluated by detecting the expression of the aforementioned oxidative stress-associated proteins, 3-NT as well as 8-oxo-deoxyguanosine (8-OHdG). In the hippocampal region, the apoptotic rate was determined using a TUNEL assay. The results demonstrated that dioscin at a dose of 400 ng/ml significantly reversed the increase in the expression levels of the inflammatory factors and attenuated those of apoptotic cytokines induced by OGD/R. Additionally, dioscin notably reversed the OGD/R-mediated activation of the HMGB-1/RAGE signaling pathway and . Cell treatment with dioscin significantly attenuated ROS production and increased the activity of antioxidant enzymes. Additionally, increasing the expression of HMGB-1 inhibited the protective effects of dioscin on cell apoptosis in the OGD/R-induced neurons. Furthermore, HMGB-1 overexpression reversed the antiapoptotic and anti-inflammatory effects of dioscin on neurons. The results of the present study indicated that dioscin exerted anti-inflammatory, antiapoptotic and antioxidant effects via the HMGB-1/RAGE signaling pathway. These results suggest a novel perspective of the protective effects of dioscin as a prospective remedial factor for IRI.
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http://dx.doi.org/10.3892/etm.2020.9361DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7604738PMC
December 2020

Risk factors for venous thromboembolism and evaluation of the modified Caprini score in patients undergoing lung resection.

J Thorac Dis 2020 Sep;12(9):4805-4816

Department of Thoracic Surgery, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China.

Background: There is a high incidence of venous thromboembolism (VTE) after lung resection, so it is necessary to identify the risk factors for VTE in these patients. It is also important to evaluate whether the modified Caprini score can accurately assess the risk of VTE in patients after lung resection.

Methods: This retrospective study included 437 patients undergoing lung resection between July 2016 and December 2017. All patients underwent lower extremities ultrasound before and after operation to determine the presence of the newly diagnosed VTE.

Results: Forty-seven (10.8%) of the 437 patients were diagnosed with VTE after lung surgery. Multivariate logistic regression analysis showed that age (OR, 2.04; 95% CI, 1.40-2.99), duration of operation (OR, 1.51; 95% CI, 1.08-2.12), lymphocyte count (OR, 0.28; 95% CI, 0.11-0.69), and D-dimer concentration (OR, 1.55; 95% CI, 1.22-1.97) were significantly associated with VTE in lung resection patients. The cut-off values for lymphocyte count and D-dimer concentration determined using receiver operating characteristic (ROC) curve were 1.15×10/L and 1.37 µg/mL respectively. The modified Caprini score divided the patients into three groups: low risk (0-4 points), moderate risk (5-8 points) and high risk (≥9 points), and the incidence of VTE was 12.3% (37/300), 7.5% (10/133) and 0% (0/4), respectively (P>0.05).

Conclusions: In this study, we identified four independent factors for VTE after lung resection patients: age, duration of operation, lymphocyte count, and D-dimer. According to the modified Caprini score, there were fewer patients in the high-risk group, and the incidence of VTE not increased with the increase of risk. Better evaluation of operation time and D-dimer may help the modified Caprini score to better assess VTE risk in these patients.
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http://dx.doi.org/10.21037/jtd-20-1279DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7578470PMC
September 2020

Gene Upregulation Might Independently Predict Shorter Progression-Free Survival in Lung Adenocarcinoma.

Technol Cancer Res Treat 2020 Jan-Dec;19:1533033820957030

Department of Thoracic Surgery, 12517Beijing Chao-Yang Hospital, Capital Medical University, Beijing, China.

Objective: This study aimed to explore expression profile, its prognostic value, and the potential genomic alterations associated with its dysregulation in lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC).

Materials And Methods: Data from The Cancer Genome Atlas (TCGA), The Genotype-Tissue Expression (GTEx), and Kaplan-Meier plotter were used in combination for bioinformatic analysis.

Results: mRNA was significantly upregulated in both LUAD and LUSC compared with their respective normal controls. upregulation showed independent prognostic value in progression-free survival (PFS) (HR: 1.169, 95%CI: 1.033 -1.322, = 0.014). mRNA expression was positively correlated with invasion, cell cycle, DNA damage, and DNA repair of LUAD cells at the single-cell level. Genomic analysis showed that gene-level amplification might not directly lead to increased PLEK2 expression. Methylation profile analysis found 4 CpG sites (cg12199376, cg14437634, cg17641252, and cg06724236) had at least a weakly negative correlation with expression, among which cg12199376, cg14437634 and cg17641252 locate around the first exon of the gene.

Conclusions: Increased expression might be a specific prognostic biomarker of poor PFS in LUAD patients. Its expression had significant positive correlations with invasion, cell cycle, DNA damage, and DNA repair of LUAD cells at the single-cell level. Promoter hypomethylation might be a potential mechanism leading to its upregulation.
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http://dx.doi.org/10.1177/1533033820957030DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7588770PMC
October 2020

Different HONO Sources for Three Layers at the Urban Area of Beijing.

Environ Sci Technol 2020 10 28;54(20):12870-12880. Epub 2020 Sep 28.

State Key Laboratory for Structural Chemistry of Unstable and Stable Species, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China.

Gaseous nitrous acid (HONO) is a crucial precursor of the hydroxyl (OH) radical, which is a "detergent" in the atmosphere. Nowadays, HONO formation mechanisms at polluted urban areas are controversial, which restricts the understanding of atmospheric oxidative capacity and radical cycling. Herein, multiday vertical observation of HONO and NO was simultaneously performed at three heights at the urban area of Beijing for the first time. The vertical distribution of HONO was often unexpected, and it had the highest HONO concentration at 120 m, followed by those at 8 and 240 m. 0D box model simulations suggest that ground and aerosol surfaces might play similar roles in NO conversion at 8 m during the whole measurement. NO conversion on aerosol surfaces was the most important HONO source aloft during haze days. At daytime, a strong missing HONO source unexpectedly existed in the urban aloft, and it was relevant to solar radiation and consumed OH.
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http://dx.doi.org/10.1021/acs.est.0c02146DOI Listing
October 2020

MicroRNA-26a Protects the Heart Against Hypertension-Induced Myocardial Fibrosis.

J Am Heart Assoc 2020 09 31;9(18):e017970. Epub 2020 Aug 31.

Department of Cardiology The Second Affiliated Hospital Xi'an Jiaotong University Xi'an Shaanxi People's Republic of China.

Background Hypertensive myocardial fibrosis (MF) is characterized by excessive deposition of extracellular matrix and cardiac fibroblast proliferation, which can lead to heart failure, malignant arrhythmia, and sudden death. In recent years, with the deepening of research, microRNAs have been found to have an important role in blood pressure control and maintaining normal ventricular structure and function. Methods and Results In this study, we first documented the downregulation of microRNA-26a (miR-26a) in the plasma and myocardium of spontaneously hypertensive rats; more importantly, miR-26a-deficient mice showed MF, whereas overexpression of miR-26a significantly prevented elevated blood pressure and inhibited MF in vivo and angiotensin II-induced fibrogenesis in cardiac fibroblasts by directly targeting connective tissue growth factor and Smad4. miR-26a inhibited cardiac fibroblast proliferation by the enhancer of zeste homolog 2/p21 pathway. Conclusions Our study identified a novel role for miR-26a in blood pressure control and hypertensive MF and provides a possible treatment strategy for miR-26a to alleviate and reverse hypertensive MF.
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http://dx.doi.org/10.1161/JAHA.120.017970DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7726969PMC
September 2020

Sodium Butyrate-Modulated Mitochondrial Function in High-Insulin Induced HepG2 Cell Dysfunction.

Oxid Med Cell Longev 2020 16;2020:1904609. Epub 2020 Jul 16.

Faculty of Chinese Medicine, State Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Taipa, Macao, China.

The liver plays a pivotal role in maintaining euglycemia. Biogenesis and function of mitochondria within hepatocytes are often the first to be damaged in a diabetic population, and restoring its function is recently believed to be a promising strategy on inhibiting the progression of diabetes. Previously, we demonstrated that the gut microbiota metabolite butyrate could reduce hyperglycemia and modulate the metabolism of glycogen in both db/db mice and HepG2 cells. To further explore the mechanism of butyrate in controlling energy metabolism, we investigated its influence and underlying mechanism on the biogenesis and function of mitochondria within high insulin-induced hepatocytes in this study. We found that butyrate significantly modulated the expression of 54 genes participating in mitochondrial energy metabolism by a PCR array kit, both the content of mitochondrial DNA and production of ATP were enhanced, expressions of histone deacetylases 3 and 4 were inhibited, beta-oxidation of fatty acids was increased, and oxidative stress damage was ameliorated at the same time. A mechanism study showed that expression of GPR43 and its downstream protein beta-arrestin2 was increased on butyrate administration and that activation of Akt was inhibited, while the AMPK-PGC-1alpha signaling pathway and expression of p-GSK3 were enhanced. In conclusion, we found in the present study that butyrate could significantly promote biogenesis and function of mitochondria under high insulin circumstances, and the GPR43--arrestin2-AMPK-PGC1-alpha signaling pathway contributed to these effects. Our present findings will bring new insight on the pivotal role of metabolites from microbiota on maintaining euglycemia in diabetic population.
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http://dx.doi.org/10.1155/2020/1904609DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7382753PMC
May 2021

The structural elucidation of aqueous HBO solutions by DFT and neutron scattering studies.

Phys Chem Chem Phys 2020 Aug;22(30):17160-17170

CAS, Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources, Key Laboratory of Salt Lake Resources Chemistry of Qinghai Province, Qinghai Institute of Salt Lakes, Chinese Academy of Sciences, Xining 810008, China.

The micro-structure of aqueous boric acid (H3BO3) solutions is of broad interest in earth sciences, geochemistry, material science, as well as chemical engineering. In the present study, the structure of aqueous H3BO3 solutions was studied via neutron scattering with 2H and 11B isotope labelling combined with empirical potential structure refinement (EPSR) modelling. In aqueous H3BO3 solutions, B(OH)3 is the dominant borate species. Density function theory (DFT) calculations show that the boron hydroxyl has a lower electrostatic potential (ESP), which makes B(OH)3 a relatively weakly hydrated, compared with the bulk water. In the 0.95 mol L-1 H3BO3 solution at 298 K (saturated), ∼18 water molecules enter the hydration sphere of B(OH)3 with the hydration distance (B-O(W)) of 3.75 Å, while only 4.23 of them hydrate with H3BO3 as the hydrogen bond (H-bond) acceptor or H-bond donor. Both neutron scattering and DFT calculations for 2B(OH)3·6H2O clusters at the ωB97XD/6-311++g(3df,3pd) basis level show that B(OH)3 forms molecular clusters in bidentate contact molecular pairs (BCMP), mono-dentate molecular pairs (MCMP), solvent-shared molecular pairs (SMP), and parallel solvent-shared molecular pairs (PSMP) in aqueous solutions. Their relative contents are both concentration- and temperature-sensitive. BCMP with the B-B distance of ∼4.1 Å is the dominant molecular pair in the aqueous solutions. Relatively less content and van der Waals interactions stabilized PSMP, with a B-B distance of ∼3.6 Å between the two parallel layers, which is a crucial species for the crystallization of H3BO3 from aqueous solution.
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http://dx.doi.org/10.1039/d0cp02306jDOI Listing
August 2020

Period-reversal accelerating self-imaging and multi-beams interference based on accelerating beams in parabolic optical potentials.

Opt Express 2020 Jul;28(14):20007-20015

Linear dynamics of an accelerating wave packet, which is produced by adding shifted copies of the fundamental Airy beam, due to parabolic optical potentials are investigated. A new type of self-imaging phenomenon, referred to as period-reversal accelerating self-imaging, is demonstrated theoretically and numerically. Unlike ordinary Talbot effects, where optical field pattern reappears at constant intervals and follows a straight line, here, the field pattern of this new self-imaging effect propagating along a periodic oscillating trajectory, can self-reproduces itself at nonconstant intervals, and begins to invert after the phase transition points, where the superposition of fundamental Airy beams forms multi-beams interference fringes. A completely spatially reversal replica of the initial field distribution is observed at odd multiplies of the period halves. Moreover, the properties of the multi-beams interference fringes are discussed in detail and can be used for the measurement of the system parameter. The above results can be generalized in the case of two transverse dimensions, where it can be treated as a product of two independent one-dimensional cases. The theoretical calculations and numerical simulations verify each other completely.
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http://dx.doi.org/10.1364/OE.395967DOI Listing
July 2020

Adiponectin Reduces Embryonic Loss Rate and Ameliorates Trophoblast Apoptosis in Early Pregnancy of Mice with Polycystic Ovary Syndrome by Affecting the AMPK/PI3K/Akt/FoxO3a Signaling Pathway.

Reprod Sci 2020 12 25;27(12):2232-2241. Epub 2020 Jun 25.

Department of Reproductive Medicine, The First Affiliated Hospital, Jinan University, 601 West Huangpu Avenue, Guangzhou, 510000, Guangdong, People's Republic Of China.

Reports in recent years have suggested that adiponectin (APN) improves insulin resistance and inhibits apoptosis by activating the AMP-activated protein kinase (AMPK) pathway and the PI3K/Akt signaling pathway after binding to its receptor. This study aims to explore the mechanism by which APN reduces embryo loss rate and trophoblast apoptosis in early pregnancy of mice with polycystic ovary syndrome (PCOS). PCOS mice were subcutaneously injected with APN (10 μg mg kg day) on 11 consecutive days from the 3rd day of pregnancy onwards to observe the change of the embryo loss rate of PCOS mice induced by APN. Quantitative real-time PCR and Western blot were used to determine the relative expressions of mRNA and the proteins AMPK, PI3K, and Akt in mouse uterine tissue. At the same time, primary cultured mouse villous trophoblast cells were used to further explore the underlying mechanisms in vitro. APN significantly reduces the pregnancy loss rate of PCOS mice. At the same time, APN increases phosphorylation and mRNA expression levels of AMPK, PI3K, and Akt in PCOS mouse uterine tissue. In addition, trophoblast cells of model mice were treated with APN and inhibitors, and APN was found to reduce trophoblast cell apoptosis by affecting the phosphorylation levels of AMPK, PI3K, Akt, and FoxO3a proteins. APN reduces the embryo loss rate and ameliorates trophoblast apoptosis in PCOS mice by affecting the AMPK/PI3K/AKT/FoxO3a signaling pathway.
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http://dx.doi.org/10.1007/s43032-020-00237-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7593319PMC
December 2020

Detection of Viable and Total Bacterial Community in the Pit Mud of Chinese Strong-Flavor Liquor Using Propidium Monoazide Combined With Quantitative PCR and 16S rRNA Gene Sequencing.

Front Microbiol 2020 26;11:896. Epub 2020 May 26.

State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China.

Microbiota in the pit mud (PM) plays a crucial role in the production of Chinese strong-flavor liquor (CSFL), the most popular distilled liquor in China. However, previous studies used total microbes, instead of viable ones, for the characterization of the microbial community in this environment. In this study, we used propidium monoazide (PMA) combined with quantitative polymerase chain reaction (qPCR) and 16S rRNA gene sequencing to verify the effect of non-viablee bacteria on the characterization of PM bacteria. After PMA concentration optimization, 50 μM PMA was chosen to pretreat 5 and 20 years PMs. The qPCR results showed that there were 50.78 and 71.84% of non-viable bacteria in the 5-year PM and 20-year PM, respectively. Both copy numbers of total bacteria and viable bacteria were significantly higher in 20-year PM than those in 5-year PM. Nevertheless, in terms of bacterial diversity and composition analyses at the operational taxonomic unit (OTU), phylum, class, and genus levels, 16S rRNA gene sequencing results displayed no significant differences between total bacteria and viable bacteria in both PM types. In conclusion, it is necessary for non-viable bacteria to be considered in determining absolute biomass of bacteria in PM, but not necessary in the analysis of diversity and composition of PM bacteria. To the best of our knowledge, our study is the first attempt to analyze viable bacteria in the PM of CSFL and provides useful information on how to accurately characterize a microbial community in a PM environment.
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http://dx.doi.org/10.3389/fmicb.2020.00896DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7264162PMC
May 2020
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