Publications by authors named "Yuanyuan Fang"

86 Publications

Vitamin D status in Mainland of China: A systematic review and meta-analysis.

EClinicalMedicine 2021 Aug 14;38:101017. Epub 2021 Jul 14.

Department of Laboratory Medicine, Tongji Hospital, Tongji Medical College, HUST, Wuhan, China.

Background: Low vitamin D (VitD) status is becoming a global health issue. Previous heterogenous results are urging a meta-analysis to delineate a panorama of VitD conditions in the general population in Mainland of China.

Methods: We performed a systematic review and meta-analysis by searching PubMed, Web of Science, EMBASE, China National Knowledge Infrastructure, WanFang, and VIP databases up to June 4, 2021. The inclusion criteria were as follows: (1) original articles or dissertations focused on VitD status of people in Mainland of China; and (2) studies were population-based, cross-sectional, or longitudinal cohort with baseline data. The outcomes were serum 25(OH)D concentration and the prevalence of low VitD status. Low VitD status included VitD deficiency (< 30 nmol/L) and VitD inadequacy (< 50 nmol/L). Data were estimated by Hierarchical Bayesian methods. All included studies were cross-sectional or longitudinal cohort studies about VitD status of people in Mainland of China. (Registration: PROSPERO CRD42021226130).

Findings: A total of 105 eligible studies including 234,519 subjects were included. In adults, the overall mean 25(OH)D concentration was 44.3 nmol/L (95% Credible Interval [CrI]: 39.8-48.7). The pooled prevalence of VitD deficiency and inadequacy was 20.7% (95% CrI: 11.9-32.9) and 63.2% (95% CrI: 53.5-72.3), respectively. In children and adolescents, the overall mean 25(OH)D concentration was 52.2 nmol/L (95% CrI: 46.7-57.5). The pooled prevalence of VitD deficiency and inadequacy was 23.0% (95% CrI: 8.9-44.3) and 46.8% (95% CrI: 37.2-56.6), respectively. Specially, we identified that the prevalence of VitD inadequacy increased with age in populations with age ≤ 18 years and ≥ 60 years.

Interpretation: Low VitD status is prominent in general population of Mainland of China, especially for adults.

Funding: National Major Scientific and Technological Special Project for "Significant New Drugs Development" (2017ZX09304022).
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.eclinm.2021.101017DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8283334PMC
August 2021

Plumbagin attenuates traumatic tracheal stenosis in rats and inhibits lung fibroblast proliferation and differentiation via TGF-β1/Smad and Akt/mTOR pathways.

Bioengineered 2021 Dec;12(1):4475-4488

Pulmonary and Critical Care Medicine of The Second Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, China.

Traumatic tracheal stenosis (TS) is a serious respiratory disease characterized by hyperplasia of airway granulation. Plumbagin (PLB) is a natural naphthoquinone component with anti-fibrotic properties. This research aimed to explore the roles of PLB in alleviating TS and the underlying mechanisms. For studies, lung fibroblasts (IMR-90 cells), with/without PLB treatment or TGF-β1 induction, were used. The viability and proliferation of IMR-90 cells were examined by CCK-8 and EdU incorporation assays. The differentiation of IMR-90 cells was assessed by detecting the mRNA and protein expression levels of collagen (COL)-1 and alpha-smooth muscle actin (α-SMA). Besides, immunofluorescence assay was conducted to evaluate the localization of α-SMA in TGF-β1-induced IMR-90 cells. Moreover, the combination of PLB with/without TβRI (SB-431,542), PI3K/Akt (Ly294002) or mTOR (rapamycin) inhibitor was pretreated on IMR-90 cells after TGF-β1 induction. For studies, a rat model of TS was established. The pathological features and severity of TS were determined by hematoxylin and eosin staining. The protein levels of TGF-β1/Smad and Akt/mTOR pathways were detected for both and models. PLB effectively inhibited the proliferation and differentiation of TGF-β1-induced IMR-90 cells, and suppressed TGF-β1/Smad and Akt/mTOR signaling pathways both and . Furthermore, PLB reduced the degree of TS in rats. Taken together, our results indicate that PLB regulates lung fibroblast activity and attenuates TS in rats by inhibiting TGF-β1/Smad and Akt/mTOR signaling pathways. In conclusion, this study implies that PLB may serve as a promising therapeutic compound for TS.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/21655979.2021.1954580DOI Listing
December 2021

Robust Yellow-Violet Pigments Tuned by Site-Selective Manganese Chromophores.

Inorg Chem 2021 Jul 14. Epub 2021 Jul 14.

Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education, School of Chemistry, Sun Yat-Sen University, Guangzhou 510275, People's Republic of China.

The rational design of multifunctional inorganic pigments relies on the manipulation of ionic valence and local surroundings of a chromophore in structurally and chemically habitable hosts. To date, the development of environmentally benign and intense violet/purple pigments is still a challenge. Here we report a family of MnTeO and MnLiTeO ( = Zn, Mg; = 0.01-0.15) pigments colored by site-selective MnO yellow and MnO violet chromophores. ZnMnTeO is intense bright yellow, comparable with commercial BiVO, and has better near-infrared reflectivity (∼89%) in comparison to commercial TiO. The codoped Li "activator" generates holes and charge-balanced Mn (MnO), realizing a color transformation from yellow to the bright violet pigments of MnLiTeO. The most vivid MgMnLiTeO is probably the best violet pigment known to date, exhibits excellent chemical and thermodynamic stability, and demonstrates pressure-dependent stability up to 5-7 GPa, before a (reversible) phase transition to pink. Theoretical calculations revealed the correlation between site-preference occupancy and chromophore motifs and predicted a wide color gamut of pigments in ZnTeO-hosted 3 transition-metal ions other than manganese.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.inorgchem.1c01568DOI Listing
July 2021

Investigation of metabolic kinetics in different brain regions of awake rats using the [H-C]-NMR technique.

J Pharm Biomed Anal 2021 Jul 7;204:114240. Epub 2021 Jul 7.

Department of Anesthesiology, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, 430071, PR China. Electronic address:

Energy metabolism and neurotransmission are necessary for sustaining normal life activities. Hence, neurological or psychiatric disorders are always associated with changes in neurotransmitters and energy metabolic states in the brain. Most studies have only focused on the most important neurotransmitters, particularly GABA and Glu, however, other metabolites such as NAA and aspartate which are also very important for cerebral function are rarely investigated. In this study, most of the metabolic kinetics information of different brain regions was investigated in awake rats using the [H-C]-NMR technique. Briefly, rats (n = 8) were infused [1-C] glucose through the tail vein for two minutes. After 20 min of glucose metabolism, the animals were sacrificed and the brain tissue was extracted and treated. Utilizing the H observed/C-edited nuclear magnetic resonance (POCE-NMR), the enrichment of neurochemicals was detected which reflected the metabolic changes in different brain regions and the metabolic connections between neurons and glial cells in the brain. The results suggest that the distribution of every metabolite differed from every brain region and the metabolic rate of NAA was relatively low at 8.64 ± 2.37 μmol/g/h. In addition, there were some correlations between several C enriched metabolites, such as Glu-Gln (p = 0.062), Glu-GABA (p < 0.01), Glx-Glx (p < 0.001), Asp-NAA (p < 0.001). This correlativity reflects the signal transmission between astrocytes and neurons, as well as the potential interaction between energy metabolism and neurotransmission. In conclusion, the current study systematically demonstrated the metabolic kinetics in the brain which shed light on brain functions and the mechanisms of various pathophysiological states.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jpba.2021.114240DOI Listing
July 2021

Serum Anti-Müllerian Hormone Levels Were Negatively Associated With Body Fat Percentage in PCOS Patients.

Front Endocrinol (Lausanne) 2021 4;12:659717. Epub 2021 Jun 4.

Center of Reproductive Medicine, Shengjing Hospital of China Medical University, Shenyang, China.

Background: Obesity is a state of excess body fat accumulation, and appears to be closely associated with polycystic ovary syndrome (PCOS). Notably, plausible biological pathways through which obesity can regulate anti-Müllerian hormone (AMH) production have been proposed, and women with PCOS characteristically have an increased AMH level. Body fat accumulation can be described by body fat percentage (BFP). However, the relationship between BFP and AMH still remains unclear.

Materials And Methods: A total of 87 controls and 156 PCOS patients were divided into lean and overweight/obese groups, and the PCOS patients were further divided into hyper-AMH and normal-AMH subgroups. Univariate regression was used to assess the unadjusted relationship between AMH and outcome variables, multivariable regression analysis was performed to test whether and how serum AMH levels were associated with BFP after adjusting for other co-variables. Receiver-operating characteristic (ROC) curve analyses were used to test the utility of BFP for the diagnosis of PCOS.

Results: BFP was higher in PCOS patients compared with controls, regardless of obesity. Serum AMH levels were negatively associated with BFP in the PCOS group (r = -0.371; < 0.001) but not in the control group (r = -0.095; = 0.385). Multivariable logistic regression analysis showed that elevated BFP was associated with a high risk of PCOS (odds ratio, 1.290; 95% confidence interval, 1.084-1.534, = 0.004). Furthermore, the combination of BFP and serum AMH into a multivariate model gave an improved area under the curve (AUC) of 88.5%, with a sensitivity of 72.4% and specificity of 87.4%; the positive and negative predictive values were 91.2% and 63.9%, respectively. One limitation of this study is all the conclusion reported was based on small sample size.

Conclusions: Herein, we described the negative correlation between BFP and serum AMH levels for the first time, and the present results highlight the importance of further investigation into the role of BFP, especially in body fat-related AMH change as it relates to the underlying pathogenesis of PCOS.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fendo.2021.659717DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8213015PMC
June 2021

Comparison of Immediate and Sequential Withdrawal of a Systemic Glucocorticoid in the Treatment of Acute Exacerbations of Chronic Obstructive Pulmonary Disease: A Multicenter, Randomized, Double-Blind, Parallel-Controlled, Open-Label Study.

Front Mol Biosci 2021 20;8:639079. Epub 2021 May 20.

Department of Respiratory and Critical Care Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.

Patients with acute exacerbations of chronic obstructive pulmonary disease (AECOPD) were treated with immediate or sequential withdrawal after 5 days of systemic glucocorticoids. The effects of the two withdrawal methods on the prognosis of patients were compared at 30, 90, 180, and 360 days after discharge. A multicenter, randomized, double-blind, parallel-controlled, open-label study was conducted in the respiratory department of tertiary hospitals in Central China. Patients met inclusion criteria for AECOPD and needed to use systemic glucocorticoids. They were randomly assigned to immediate and sequential withdrawal groups at a 1:1 ratio. The study was completed in August 2020 and is registered at the China Clinical Trials Registry (Chictr.org) (ChiCTR1800018894). According to general data and clinical characteristics, there were no statistically significant differences between the 329 patients in the immediate withdrawal group and the 310 patients in the sequential withdrawal group ( > 0.05). At the 30, 90, 180, and 360-days follow-up, the acute exacerbation frequency, rehospitalization rate, mortality, and intensive care unit (ICU) treatment rate were not significantly different between the immediate withdrawal group and sequential withdrawal group ( > 0.05). The modified Medical Research Council (mMRC) and COPD assessment test (CAT) scores were also not significantly different between the two groups. At the 180- and 360-day follow-up, forced expiratory volume in 1 s (FEV1%) and peak expiratory flow (PEF) were not significantly different between the two groups ( > 0.05). The time from discharge to first acute exacerbation was significantly lower in the immediate withdrawal group (46.12 days) than in sequential withdrawal group (49.02 days) ( < 0.05). The time of stay in the hospital for the first time after discharge was not significantly different between the two groups ( > 0.05). Adverse events were not significantly different between the immediate withdrawal group and sequential withdrawal group ( < 0.05). Subgroup analysis was performed according to age, degree of disease, and relevant indicators. At the 30-day follow-up, the acute exacerbation frequency of patients with advanced age, high global strategy for chronic obstructive lung disease (GOLD), and high fractional exhaled nitric oxide was significantly higher in the immediate withdrawal group than in the sequential withdrawal group ( < 0.05). In addition, according to receiver operating characteristic (ROC) curve analysis, the frequency of acute exacerbations at the 30-day follow-up was significantly higher in patients with age > 63.5 years or GOLD > 3 in the immediate withdrawal group than in the sequential withdrawal group, suggesting that the short-term efficacy was poor.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fmolb.2021.639079DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8173198PMC
May 2021

Genetic architecture of the metabolic pathway of salicylic acid biosynthesis in Populus.

Tree Physiol 2021 May 13. Epub 2021 May 13.

National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China.

Salicylic acid (SA) is a vital hormone for adaptive responses to biotic and abiotic stresses, which facilitating growth-immunity trade-offs in plants. However, the genetic regulatory networks underlying the metabolic pathway of SA biosynthesis in perennial species remain unclear. Here, we integrated genome-wide association study (GWAS) with metabolite and expression profiling methodologies to dissect the genetic architecture of SA biosynthesis in Populus. First, we quantified nine intermediate metabolites of SA biosynthesis in 300 unrelated Populus tomentosa individuals. Then, we used a systematic genetic strategy to identify candidate genes for constructing the genetic regulatory network of SA biosynthesis. We focused on WRKY70, an efficient transcription factor, as the key causal gene in the regulatory network, and combined the novel genes coordinating the accumulation of SA. Finally, we identified eight GWAS signals and eight eQTLs situated in a selective sweep, and showed the presence of large allele frequency differences among the three geographic populations, revealing that candidate genes subject to selection were involved in SA biosynthesis. This study provides an integrated strategy for dissecting the genetic architecture of the metabolic pathway of salicylic acid biosynthesis in Populus, thereby enhancing our understanding of genetic regulation of SA biosynthesis in trees, and accelerating marker-assisted breeding efforts toward high-resistance elite varieties of Populus.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/treephys/tpab068DOI Listing
May 2021

The effect of multi-dimensional postpartum visits on increasing the breastfeeding rate of parturients with inverted nipple: a randomised study.

Ann Palliat Med 2021 Mar;10(3):3078-3085

Obstetrics Department, Drum Tower Hospital Affiliated to Nanjing University School of Medicine, Nanjing, China.

Background: Postpartum breastfeeding is an effective guarantee for the healthy growth of newborns. Vigorously promoting breastfeeding has substantial benefits for the physical and mental health of mothers and babies, and can also benefit the entire society. The purpose of this study was to explore the effect of multi-dimensional postpartum visits (MDPV) applied to parturients with inverted nipple on improving breastfeeding rates.

Methods: A total of 114 parturients with inverted nipples who gave birth in the Drum Tower Hospital Affiliated to Nanjing University School of Medicine from October 2018 to October 2019 and successfully breastfed in the hospital were selected. The patients were divided into two groups according to the random number table method, with 57 cases in each group. The control group received routine postpartum visits, while the observation group received MDPV. Breastfeeding knowledge, rate of exclusive breastfeeding, incidence of maternal mastitis, rate of infant hospitalization, and level of self-efficacy were compared between the two groups.

Results: Breastfeeding knowledge and the rate of exclusive breastfeeding at 1, 3, and 6 months after discharge in the observation group were higher than those in the control group (P<0.05). The incidence of maternal mastitis and the rate of infant hospitalization in the observation group were lower than those in the control group (P<0.05). The self-efficacy scores of the observation group at 1 and 6 months after discharge were higher than those of the control group (P<0.05).

Conclusions: The application of MDPV to parturients with inverted nipples can improve the breast-feeding rate, enhance breastfeeding knowledge, reduce the incidence of maternal mastitis and infant hospitalization rate, and improve breastfeeding self-efficacy. Thus, it is worthy of promotion.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21037/apm-21-165DOI Listing
March 2021

A fifty percent leucine-restricted diet reduces fat mass and improves glucose regulation.

Nutr Metab (Lond) 2021 Mar 26;18(1):34. Epub 2021 Mar 26.

CAS Key Laboratory of Nutrition, Metabolism and Food Safety, Innovation Center for Intervention of Chronic Disease and Promotion of Health, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 320 Yueyang Road, Shanghai, 200031, China.

Background: Leucine deprivation modulates the dietary amino acid composition, reducing the fat content and improving the glucose tolerance, thus protecting the organism against obesity. However, a complete deprivation of leucine can lead to an extremely rapid fat loss in mice, accompanied by prolonged adverse effects such as weakness and mental fatigue. Therefore, in this study we aimed to seek the optimal concentration of dietary leucine that can reduce fat mass and improve the metabolism without the onset of severe effects.

Methods: To investigate whether there is a better concentration of diet leucine restriction (LR), based on the diet we conducted (A10021B), that can reduce fat mass and improve metabolism status without taking many negative effects, we fed 8 weeks old male C57Bl/6J mice with increasing degrees of leucine restriction diet 0% LR (control group), 25% LR, 50% LR, and 75% LR groups (4-6 mice each group). Fat mass and blood glucose levels were measured. The expression levels of genes involved in lipid metabolism in white adipose tissue (WAT) and liver, and proteins in insulin signaling were assessed in WAT, liver and muscle.

Results: We found that the 50% LR group is the most proper group here at the lowest leucine effective concentration, which reduced fat mass (p < 0.05) and improved glucose regulation in mice over a 90 days feeding. Further studies revealed that lipid synthesis pathway (Fas, Scd1and Srebp1, p < 0.05) was downregulated and lipolysis (Atgl, p < 0.05) was upregulated in WAT in 50% LR group, compared to that in control group. Furthermore, glucose regulation (glucose tolerance test, p < 0.05) was also improved, and insulin signaling (p < 0.05) in the muscle was enhanced in 50% LR group while in WAT and liver were not changed.

Conclusions: Collectively, a 50% LR in mice reduced fat mass and improved glucose regulation, which may function through modulating lipid synthesis and lipolysis pathway in adipose tissue as well as enhancing insulin signaling in muscle. So far, we provide a further consideration for carrying out the diet of leucine restriction to reduce fat and improve metabolism status before clinical study.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s12986-021-00564-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7995702PMC
March 2021

Genome-wide association studies reveal the coordinated regulatory networks underlying photosynthesis and wood formation in Populus.

J Exp Bot 2021 Mar 18. Epub 2021 Mar 18.

Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, Beijing Forestry University, Beijing, P. R. China.

Photosynthesis and wood formation underlie the ability of trees to provide renewable resources and perform ecosystem services; however, the genetic basis and regulatory pathways coordinating these two linked processes remain unclear. Here, we used a systems genetics strategy, integrating genome-wide association study, transcriptomic analyses, and transgenic experiments, to investigate the genetic architecture of photosynthesis and wood properties among 435 unrelated individuals of Populus tomentosa and unravel the coordinated regulatory networks causative of two trait categories. We totally detected 222 significant single-nucleotide polymorphisms, annotated to 177 candidate genes, for 10 traits of photosynthesis and wood properties. Epistasis uncovered 74 epistatic interactions for phenotypes. Strikingly, we deciphered the coordinated regulation patterns of pleiotropic genes underlying phenotypic variations for two trait categories. Furthermore, expression quantitative trait nucleotide mapping and coexpression analysis were integrated to unravel the potential transcriptional regulatory networks of candidate genes coordinating photosynthesis and wood properties. Finally, we heterologously expressed two pleiotropic genes, PtoMYB62 and PtoMYB80, in Arabidopsis thaliana, and demonstrated that they coordinate regulatory networks balancing photosynthesis and stem secondary cell wall components, respectively. Our study provides insight into the regulatory mechanisms coordinating photosynthesis and wood formation in poplar, which will accelerate the genetic breeding in trees via molecular design.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/jxb/erab122DOI Listing
March 2021

Genetic Architecture Underlying the Metabolites of Chlorogenic Acid Biosynthesis in .

Int J Mol Sci 2021 Feb 27;22(5). Epub 2021 Feb 27.

National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, China.

Chlorogenic acid (CGA) plays a crucial role in defense response, immune regulation, and the response to abiotic stress in plants. However, the genetic regulatory network of CGA biosynthesis pathways in perennial plants remains unclear. Here, we investigated the genetic architecture for CGA biosynthesis using a metabolite-based genome-wide association study (mGWAS) and expression quantitative trait nucleotide (eQTN) mapping in a population of 300 accessions of . In total, we investigated 204 SNPs which were significantly associated with 11 metabolic traits, corresponding to 206 genes, and were mainly involved in metabolism and cell growth processes of . We identified 874 eQTNs representing 1066 genes, in which the expression and interaction of causal genes affected phenotypic variation. Of these, 102 genes showed significant signatures of selection in three geographical populations, which provided insights into the adaptation of CGA biosynthesis to the local environment. Finally, we constructed a genetic network of six causal genes that coordinately regulate CGA biosynthesis, revealing the multiple regulatory patterns affecting CGA accumulation in . Our study provides a multiomics strategy for understanding the genetic basis underlying the natural variation in the CGA biosynthetic metabolites of , which will enhance the genetic development of abiotic-resistance varieties in forest trees.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/ijms22052386DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7957499PMC
February 2021

Signal transduction associated with lead-induced neurological disorders: A review.

Food Chem Toxicol 2021 Apr 14;150:112063. Epub 2021 Feb 14.

Department of Toxicology, School of Public Health, Guangxi Medical University, No. 22, Shuang-yong Rd, Nanning, 530021, Guangxi, China; Guangxi Colleges and Universities Key Laboratory of Prevention and Control of Highly Prevalent Diseases, Guangxi Medical University, Nanning, China. Electronic address:

Lead is a heavy metal pollutant that is widely present in the environment. It affects every organ system, yet the nervous system appears to be the most sensitive and primary target. Although many countries have made significant strides in controlling Pb pollution, Pb poisoning continuous to be a major public health concern. Exposure to Pb causes neurotoxicity that ranges from neurodevelopmental disorders to severe neurodegenerative lesions, leading to impairments in learning, memory, and cognitive function. Studies on the mechanisms of Pb-induced nervous system injury have convincingly shown that this metal can affect a plethora of cellular pathways affecting on cell survival, altering calcium dyshomeostasis, and inducing apoptosis, inflammation, energy metabolism disorders, oxidative stress, autophagy and glial stress. This review summarizes recent knowledge on multiple signaling pathways associated with Pb-induced neurological disorders in vivo and in vitro.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.fct.2021.112063DOI Listing
April 2021

Sodium P-aminosalicylic Acid Attenuates Manganese-Induced Neuroinflammation in BV2 Microglia by Modulating NF-κB Pathway.

Biol Trace Elem Res 2021 Jan 14. Epub 2021 Jan 14.

Department of Toxicology, School of Public Health, Guangxi Medical University, Shuang-yong Road No.22, Nanning, 530021, Guangxi, China.

Exposure to high levels of manganese (Mn) leads to brain Mn accumulation, and a disease referred to as manganism. Activation of microglia plays an important role in Mn-induced neuroinflammation. Sodium p-aminosalicylic acid (PAS-Na) is a non-steroidal anti-inflammatory drug that inhibits Mn-induced neuroinflammation. The aim of the current study was to explore the role of NF-κB in the protective mechanism of PAS-Na on Mn-induced neuroinflammation in BV2 microglial experimental model. We treated BV2 microglia with 200 μM Mn for 24 h followed by 48 h treatment with graded concentrations of PAS-Na, using an NF-kB inhibitor, JSH-23, as a positive control. MTT results established that 200 and 400 μM PAS-Na treatment increased the Mn-induced cell viability reduction. NF-κB (P65) mRNA expression and the phosphorylation of p65 were increased in Mn-treated BV2 cell, and suppressed by PAS-Na, analogous to the effect of JSH-23 pretreatment. Furthermore, PAS-Na significantly reduced the contents of the inflammatory cytokine TNF-α and IL-1β, both of which were increased by Mn treatment. The current results show that PAS-Na attenuated Mn-induced inflammation by abrogating the activation of the NF-κB signaling pathways and reduced the release of pro-inflammatory cytokines.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s12011-021-02581-wDOI Listing
January 2021

Sodium P-aminosalicylic Acid Inhibits Manganese-Induced Neuroinflammation in BV2 Microglial Cells via NLRP3-CASP1 Inflammasome Pathway.

Biol Trace Elem Res 2021 Sep 6;199(9):3423-3432. Epub 2020 Nov 6.

Department of Toxicology, School of Public Health, Guangxi Medical University, No. 22, Shuang-yong Rd, Nanning, 530021, Guangxi, China.

Background: Sodium p-aminosalicylic acid (PAS-Na) was reported to exhibit anti-inflammatory effect in the nervous system. However, the mechanism by which PAS-Na exhibits anti-inflammatory effects on manganese (Mn)-stimulated BV2 microglia cells remains unclear. Thus, this study investigated the role of PAS-Na in Mn-stimulated BV2 microglial cells.

Methods: Microglia-like BV2 were treated with MnCl with or without the non-steroidal anti-inflammatory drug PAS-Na for 12 or 24 h to examine cell viability using MTT; for 24 or 48 h to examine levels of NLRP3, CASP1, IL-1β, and IL-18 mRNA using Real-Time quantitative PCR; for 48 h to examine levels of NLRP3 and CASP1 inflammasomes, measured by western blot analysis; and for 48 h to examine levels of inflammatory cytokines, measured by enzyme-linked immunosorbent assay.

Results: The MTT assay showed that PAS-Na produced significant neuroprotective effect by preventing Mn-induced inflammation in BV2 microglial cells. PAS-Na significantly concentration and time dependently inhibited Mn-induced production of NLRP3, CASP1, IL-1β, and IL-18.

Conclusion: Taken together, our results suggest that PAS-Na exerts anti-inflammatory effects in Mn-stimulated BV2 microglial cells via downregulation of NLRP3, CASP1, IL-1β, and I L-18. Furthermore, a high concentration and prolonged PAS-Na treatment appear necessary for its therapeutic efficacy. Taken together, we conclude that PAS-Na affords therapeutic efficacy in mitigating neurological conditions associated with neuroinflammation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s12011-020-02471-7DOI Listing
September 2021

Polylysine-modified MXene nanosheets with highly loaded glucose oxidase as cascade nanoreactor for glucose decomposition and electrochemical sensing.

J Colloid Interface Sci 2021 Mar 26;586:20-29. Epub 2020 Oct 26.

Department of Chemistry, Fudan University, Shanghai 200433, PR China; College of Chemistry & Materials Engineering, Wenzhou University, Wenzhou 325027, Zhejiang, PR China. Electronic address:

Two-dimensional (2D) nanoreactors with cascade catalytic activity for glucose oxidation and hydrogen peroxide decomposition are prepared via immobilizing glucose oxidase (GOx) on TiC MXene nanosheets. Amino-rich polypeptide, poly-l-lysine (PLL), is applied to modify the ultra-thin TiC MXene nanosheets with a compatible surface for GOx immobilization. The PLL-modified TiC nanosheets possess a positively charged surface and show an excellent GOx loading capacity as high as 50 wt% of the TiC nanosheets. The physically adsorbed enzymes are then cross-linked with the amine groups in the PLL chains to form a robust GOx-PLL network covered on the MXene nanosheets. The GOx-conjugated TiC-PLL (TiC-PLL-GOx) nanosheets showed superior enzymatic activities than the activities of GOx immobilized on an inert porous silica substrate, largely because that the TiC nanosheets can catalyze the decomposition of the toxic intermediate HO generated from the glucose oxidation. Given the excellent electrical conductivity of TiC MXene, the TiC-PLL-GOx nanosheets are further deposited on glassy carbon electrode to construct a high-performance biosensor with a glucose detection limit of 2.6 μM.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jcis.2020.10.065DOI Listing
March 2021

Facile Heterogeneous and Homogeneous Anion Induced Electrosynthesis: An Efficient Method for Obtaining π-Extended Porphyrins.

Inorg Chem 2020 Nov 3;59(22):16737-16746. Epub 2020 Nov 3.

Department of Chemistry, University of Houston, Houston, Texas 77204-5003, United States.

Two closely related electrosynthetic approaches are applied for the preparation of novel π-extended tetraphenylporphyrins from malononitrile-appended β di-fused porphyrins, represented as MTPP(MN), where TPP = the dianion of tetraphenylporphyrin and MN = malononitrile. The first method involves application of a controlled reducing potential at a platinum electrode in CHCl, while the second proceeds via cyanide anion induced electron transfer. Both methods produced the same decyanated, π-extended di-fused porphyrins represented as MTPP(VCN) where VCN = vinyl cyanide and M = H, Ni, Cu, or Zn in almost quantitative yields. The final isolated and purified porphyrin products are characterized by a split Soret band ranging from 411-497 nm and two broad intense Q bands. The new π-extended porphyrins are easier to reduce than the parent MTPP or MTPP(MN) compounds by 760-800 mV and 180-190 mV, respectively, and possess an electrochemical HOMO-LUMO gap ranging from 1.48 to 1.66 V. They are also characterized by two reversible one-electron ring-centered reductions in CHCl and three reversible one-electron ring-centered reductions in THF. A fourth irreversible reduction is seen in THF at more negative potentials and is assigned to one or two of the fused cyanobenzene rings of the macrocycle.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.inorgchem.0c02770DOI Listing
November 2020

Solvent and Anion Effects on the Electrochemistry of Manganese Dipyrrin-Bisphenols.

Inorg Chem 2020 Nov 16;59(21):15913-15927. Epub 2020 Oct 16.

Department of Chemistry, University of Houston, Houston, Texas 77204-5003 United States.

A series of "NO-type" manganese dipyrrin-bisphenols (DPP), formulated as (Ar)DPPMn, where Ar = pentafluorophenyl (FPh), phenyl (Ph), or mesityl (Mes), were electrochemically and spectroscopically characterized in nonaqueous media with and without added anions in the form of tetrabutylammonium salts (TBAX where X = ClO, PF, BF, F, Cl, OH, or CN). Two major one-electron reductions are observed under most solution conditions, the first of which is assigned as a Mn process and the second as electron addition to the π-ring system as confirmed by spectroelectrochemistry. Each Mn complex also exhibits one or two one-electron oxidations, the exact number depending upon the positive potential limit of the electrochemical solvent. The two oxidations are separated by 580-590 mV in CHCN containing 0.1 M TBAPF and are assigned as π-ring-centered electron transfers to stepwise form a (Ar)DPPMn π-cation radical and dication under these solution conditions. Comparisons are made between redox properties of (Ar)DPPMn and manganese(III) porphyrins, corroles, and corrolazines each of which contains an innocent trianionic complexing ligand. The redox behavior and spectroscopic properties of [(Ar)DPPMn] where = 0, -1, or +1 are also compared to that of other structurally related [(Ar)DPPM] complexes under similar solution conditions where M = Co, Cu, B, or Au.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.inorgchem.0c02416DOI Listing
November 2020

IGF2BP3 May Contributes to Lung Tumorigenesis by Regulating the Alternative Splicing of PKM.

Front Bioeng Biotechnol 2020 2;8:679. Epub 2020 Sep 2.

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

RNA binding proteins (RBPs) play a key role in genome regulation. Here we report the post-transcript regulation of IGF2BP3, which belongs to the insulin-like growth factor 2 mRNA binding protein family. We used iRIP-seq and RNA-seq to analyze the transcript regulation and alternative splicing on IGF2BP3 treated with overexpression cells and control. Overexpressed IGF2BP3 has broadly increased genes expression which involved in G-protein coupled receptor signaling pathway, positive regulation of cell proliferation, and signal transduction. IGF2BP3 regulated alternative splicing of multiple genes mainly clustered at response to hypoxia, negative regulation of transcription, and embryonic development. This study first provides alternative splicing analysis on transcription level of IGF2BP3 regulation, which laid the foundation for later research on IGF2BP3 critical functions.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fbioe.2020.00679DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7492387PMC
September 2020

ARNTL2 promotes pancreatic ductal adenocarcinoma progression through TGF/BETA pathway and is regulated by miR-26a-5p.

Cell Death Dis 2020 08 10;11(8):692. Epub 2020 Aug 10.

General Geriatrics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China.

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive malignancies and the therapeutic outcomes remain undesirable. Increasing evidence shows that aryl hydrocarbon receptor nuclear translocator like 2 (ARNTL2) plays crucial roles in tumorigenesis of multiple tumors. However, the expression status and functions of ARNTL2 in PDAC remain elusive. Here we showed that ARNTL2 expression was markedly upregulated in PDAC tissues and cell lines. elevated expression of ARNTL2 was positively related to unfavorable prognosis. Knockdown of ARNTL2 could suppress motility and invasive ability of PDAC cells in vitro, as well as tumor development in vivo. In addition, microRNA-26a-5p (miR-26a-5p) was identified as the crucial specific arbitrator for ARNTL2 expression and the expression of miR-26a-5p was inversely correlated with ARNTL2 expression in PDAC tissues. Functionally, elevated expression of miR-26a-5p was found to inhibit the proliferation, migration, and invasion of PDAC cells in vitro, while ARNTL2 increased expression could partially abolish the suppressive effect of miR-26a-5p. Mechanism study indicated that elevated expression of miR-26a-5p suppressed TGF/BETA signaling pathway by targeting ARNTL2 in PDAC cells. In conclusion, our data suggested that ARNTL2 acted as an oncogene to regulate PDAC growth. MiR-26a-5p/ARNTL2 axis may be a novel therapeutic candidate target in PDAC treatment.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41419-020-02839-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7443143PMC
August 2020

Author Correction: Modeling suggests fossil fuel emissions have been driving increased land carbon uptake since the turn of the 20th Century.

Sci Rep 2020 Aug 10;10(1):13618. Epub 2020 Aug 10.

Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831, USA.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-020-70342-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7417547PMC
August 2020

Cerebral Small-Vessel Disease and Risk of Incidence of Depression: A Meta-Analysis of Longitudinal Cohort Studies.

J Am Heart Assoc 2020 08 25;9(15):e016512. Epub 2020 Jul 25.

Department of Neurology Tongji Hospital Wuhan China.

Background Results of several longitudinal cohort studies suggested an association between cerebral small-vessel disease and depression. Therefore, we performed a meta-analysis to explore whether cerebral small-vessel disease imparts increased risk for incident depression. Methods and Results We searched prospective cohort studies relevant to the relationship between cerebral small-vessel disease and incident depression published through September 6, 2019, which yielded 16 cohort studies for meta-analysis based on the relative odds ratio (OR) calculated with fixed- and random-effect models. Baseline white matter hyperintensities (WMHs) (pooled OR, 1.37; 95% CI, 1.14-1.65), enlarged perivascular spaces (pooled OR, 1.33; 95% CI, 1.03-1.71), and cerebral atrophy (pooled OR, 2.83; 95% CI, 1.54-5.23) were significant risk factors for incident depression. Presence of deep WMHs (pooled OR, 1.47; 95% CI, 1.05-2.06) was a stronger predictor of depression than were periventricular WMHs (pooled OR, 1.31; 95% CI, 0.93-1.86). What's more, the pooled OR increased from 1.20 for the second quartile to 1.96 for the fourth quartile, indicating that higher the WMH severity brings greater risk of incident depression (25th-50th: pooled OR, 1.20; 95% CI, 0.68-2.12; 50th-75th; pooled OR, 1.42; 95% CI, 0.81-2.46; 75th-100th: OR, 1.96; 95% CI, 1.06-3.64). These results were stable to subgroup analysis for age, source of participants, follow-up time, and methods for assessing WMHs and depression. Conclusions Cerebral small-vessel disease features such as WMHs, enlarged perivascular spaces, and cerebral atrophy, especially the severity of WMHs and deep WMHs, are risk factors for incident depression.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1161/JAHA.120.016512DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7792262PMC
August 2020

Modeling suggests fossil fuel emissions have been driving increased land carbon uptake since the turn of the 20th Century.

Sci Rep 2020 06 3;10(1):9059. Epub 2020 Jun 3.

Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831, USA.

Terrestrial vegetation removes CO from the atmosphere; an important climate regulation service that slows global warming. This 119 Pg C per annum transfer of CO into plants-gross primary productivity (GPP)-is the largest land carbon flux globally. While understanding past and anticipated future GPP changes is necessary to support carbon management, the factors driving long-term changes in GPP are largely unknown. Here we show that 1901 to 2010 changes in GPP have been dominated by anthropogenic activity. Our dual constraint attribution approach provides three insights into the spatiotemporal patterns of GPP change. First, anthropogenic controls on GPP change have increased from 57% (1901 decade) to 94% (2001 decade) of the vegetated land surface. Second, CO fertilization and nitro  gen deposition are the most important drivers of change, 19.8 and 11.1 Pg C per annum (2001 decade) respectively, especially in the tropics and industrialized areas since the 1970's. Third, changes in climate have functioned as fertilization to enhance GPP (1.4 Pg C per annum in the 2001 decade). These findings suggest that, from a land carbon balance perspective, the Anthropocene began over 100 years ago and that global change drivers have allowed GPP uptake to keep pace with anthropogenic emissions.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-020-66103-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7271159PMC
June 2020

Old Dog, New Tricks: Innocent, Five-coordinate Cyanocobalt Corroles.

Inorg Chem 2020 Jun 26;59(12):8562-8579. Epub 2020 May 26.

Department of Chemistry, University of Houston, Houston 77204-5003, Texas, United States.

Three mono-CN ligated anionic cobalt A-triarylcorroles were synthesized and investigated as to their spectroscopic and electrochemical properties in CHCl, pyridine (Py), and dimethyl sulfoxide (DMSO). The newly synthesized corroles provide the first examples of air-stable cobalt corroles with an anionic axial ligand and are represented as [(Ar)CorCo(CN)]TBA, where Cor is the trivalent corrole macrocycle, Ar is -(CN)Ph, -(CF)Ph, or -(OMe)Ph, and TBA is the tetra--butylammonium (TBA) cation. Multiple redox reactions are observed for each mono-CN derivative with a key feature being a more facile first oxidation and a more difficult first reduction in all three solvents as compared to all previously examined corroles with similar and β-pyrrole substituents. Formation constants (log ) for conversion of the five-coordinate mono-CN complex to its six-coordinate bis-CN form ranged from 10 for Ar = -(OMe)Ph to 10 for Ar = -(CN)Ph in DMSO as determined by spectroscopic methodologies. The in situ generated bis-CN complexes, represented as [(Ar)CorCo(CN)](TBA), and the mixed ligand complexes, represented as [(Ar)CorCo(CN)(Py)]TBA, were also investigated as to their electrochemical and spectroscopic properties. UV-visible spectra and electrode reactions of the synthesized mono-CN derivatives are compared with the neutral mono-DMSO cobalt corrole complexes and the in situ generated bis-CN and bis-Py complexes, and the noninnocent (or innocent) nature of each cobalt corrole system is addressed. The data demonstrate the ability of the CN axial ligand(s) to stabilize the high-valent forms of the metallocorrole, leading to systems with innocent macrocyclic ligands. Although a number of six-coordinate cobalt(III) corroles with N-donor ligands were characterized in the solid state, a dissociation of one axial ligand readily occurs in nonaqueous solvents, and this behavior contrasts with the high stability of the currently studied bis-CN adducts in CHCl, pyridine, or DMSO. Linear free energy relationships were elucidated between the -phenyl Hammett substituent constants (Σσ) and the measured binding constants, the redox potentials, and the energy of the band positions in the mono-CN and bis-CN complexes in their neutral or singly oxidized forms, revealing highly predictable trends in the physicochemical properties of the anionic corroles.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.inorgchem.0c01037DOI Listing
June 2020

Sphingosine 1-phosphate promotes the proliferation of olfactory ensheathing cells through YAP signaling and participates in the formation of olfactory nerve layer.

Glia 2020 09 14;68(9):1757-1774. Epub 2020 Feb 14.

Department of Orthopedics (Spine Surgery), Wenzhou Medical University First Affiliated Hospital, Wenzhou, Zhejiang, China.

Olfactory ensheathing cells (OECs) are unique glial cells with axonal growth-promoting properties in the olfactory epithelium and olfactory bulb, covering the entire length of the olfactory nerve. The proliferation of OECs is necessary for the formation of the presumptive olfactory nerve layer (ONL) during development and OECs transplantation. However, the molecular mechanism underlying the regulation of OEC proliferation in the ONL still remains unknown. In the present study, we examined the role of sphingosine 1-phosphate (S1P) and S1P receptors (S1PRs) on OEC proliferation. Initially, reverse transcription-PCR (RT-PCR), western blot and immunostaining revealed that S1PRs were highly expressed in the OECs in vitro and in vivo. Furthermore, we found that S1P treatment promoted the proliferation of primary cultured OECs mediated by S1PR1. Mechanistically, yes-associated protein (YAP) was required for S1P-induced OEC proliferation through RhoA signaling. Finally, conditional knockout of YAP in OECs reduced OEC proliferation in ONL, which impaired the axonal projection and growth of olfactory sensory neurons, and olfactory functions. Taken together, these results reveal a previously unrecognized function of S1P/RhoA/YAP pathway in the proliferation of OECs, contributing to the formation of ONL and the projection, growth, and function of olfactory sensory neurons during development.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/glia.23803DOI Listing
September 2020

A Universal Surrogate Reporter for Efficient Enrichment of CRISPR/Cas9-Mediated Homology-Directed Repair in Mammalian Cells.

Mol Ther Nucleic Acids 2020 Mar 24;19:775-789. Epub 2019 Dec 24.

Key Laboratory of Animal Genetics, Breeding and Reproduction of Shaanxi Province, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China. Electronic address:

CRISPR/Cas9-mediated homology-directed repair (HDR) can be leveraged to precisely engineer mammalian genomes. However, the inherently low efficiency of HDR often hampers to identify the desired modified cells. Here, we developed a novel universal surrogate reporter system that efficiently enriches for genetically modified cells arising from CRISPR/Cas9-induced HDR events (namely, the "HDR-USR" system). This episomally based reporter can be self-cleaved and self-repaired via HDR to create a functional puromycin selection cassette without compromising genome integrity. Co-transfection of the HDR-USR system into host cells and transient puromycin selection efficiently achieves enrichment of HDR-modified cells. We tested the system for precision point mutation at 16 loci in different human cell lines and one locus in two rodent cell lines. This system exhibited dramatic improvements in HDR efficiency at a single locus (up to 20.7-fold) and two loci at once (42% editing efficiency compared to zero in the control), as well as greatly improved knockin efficiency (8.9-fold) and biallelic deletion (35.9-fold) at test loci. Further increases were achieved by co-expression of yeast Rad52 and linear single-/double-stranded DNA donors. Taken together, our HDR-USR system provides a simple, robust and efficient surrogate reporter for the enrichment of CRISPR/Cas9-induced HDR-based precision genome editing across various targeting loci in different cell lines.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.omtn.2019.12.021DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6970138PMC
March 2020

Structural, Photophysical, and Electrochemical Properties of Doubly Fused Porphyrins and Related Fused Chlorins.

Inorg Chem 2020 Jan 31;59(2):1481-1495. Epub 2019 Dec 31.

Department of Chemistry , University of Houston , Houston , Texas 77204-5003 , United States.

The electrochemical and physicochemical properties of tetraphenylporphyrins and tetraphenylchlorins with two fused indanedione (IND) or malononitrile (MN) groups and two antipodal Br, Ph, or H β-substituents are investigated in nonaqueous media. These compounds were synthesized by oxidative fusion of free-base -chlorins, followed by metalation. The corresponding free-base di-fused chlorins were also isolated as intermediates and characterized for comparisons. The examined di-fused porphyrins (DFP) and di-fused chlorins (DFC) are represented as MDFP(Y)(R) and HDFC(Y)(R), where M = 2H, Cu, Ni, Zn, and Co, Y is a fused indanedione (IND) or malononitrile group (MN), and R = H, Br, or Ph. The IND- and MN-appended compounds in both series exhibit the expected two one-electron oxidations but quite different redox behavior is observed upon reduction, where the free-base IND-appended chlorins show four reversible one-electron reductions, compared to only two for the related free-base MN-appended chlorins. Although porphyrin trianions and tetraanions have been recently described for derivatives with highly electron-withdrawing and/or π-extending substituents, this seems not to be the case for the doubly fused IND-chlorins, where the first two one-electron additions are proposed to be located at the conjugated macrocycle and the last two at the fused IND groups, each of which is reduced at a different potential, consistent with the behavior expected for two equivalent and interacting redox centers. Unlike the examined chlorins, which are all stable in their electroreduced forms, the electrogenerated anionic forms of the di-fused porphyrins are all highly reactive and characterized by cyclic voltammograms having reduction peaks not only for the synthesized compounds added to solution but also for one or more new redox active species formed at the electrode surface in homogeneous chemical reactions following electron transfer. Comparisons are made between electrochemical behavior of the structurally related porphyrins and chlorins and the sites of electron transfer assigned on the basis of known electrochemical diagnostic criteria. One of the compounds, ZnDFP(MN), was also structurally characterized as having a ruffled and twisted macrocyclic conformation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.inorgchem.9b03329DOI Listing
January 2020

Global vegetation biomass production efficiency constrained by models and observations.

Glob Chang Biol 2020 03 27;26(3):1474-1484. Epub 2019 Sep 27.

Department of Atmospheric and Oceanic Science, University of Maryland, College Park, MD, USA.

Plants use only a fraction of their photosynthetically derived carbon for biomass production (BP). The biomass production efficiency (BPE), defined as the ratio of BP to photosynthesis, and its variation across and within vegetation types is poorly understood, which hinders our capacity to accurately estimate carbon turnover times and carbon sinks. Here, we present a new global estimation of BPE obtained by combining field measurements from 113 sites with 14 carbon cycle models. Our best estimate of global BPE is 0.41 ± 0.05, excluding cropland. The largest BPE is found in boreal forests (0.48 ± 0.06) and the lowest in tropical forests (0.40 ± 0.04). Carbon cycle models overestimate BPE, although models with carbon-nitrogen interactions tend to be more realistic. Using observation-based estimates of global photosynthesis, we quantify the global BP of non-cropland ecosystems of 41 ± 6 Pg C/year. This flux is less than net primary production as it does not contain carbon allocated to symbionts, used for exudates or volatile carbon compound emissions to the atmosphere. Our study reveals a positive bias of 24 ± 11% in the model-estimated BP (10 of 14 models). When correcting models for this bias while leaving modeled carbon turnover times unchanged, we found that the global ecosystem carbon storage change during the last century is decreased by 67% (or 58 Pg C).
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/gcb.14816DOI Listing
March 2020

Pressure-Induced Emission (PIE) and Phase Transition of a Two-dimensional Halide Double Perovskite (BA) AgBiBr (BA=CH (CH ) NH ).

Angew Chem Int Ed Engl 2019 Oct 11;58(43):15249-15253. Epub 2019 Sep 11.

State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun, 130012, China.

Two-dimensional (2D) halide perovskites have attracted significant attention due to their compositional flexibility and electronic diversity. Understanding the structure-property relationships in 2D double perovskites is essential for their development for optoelectronic applications. In this work, we observed the emergence of pressure-induced emission (PIE) at 2.5 GPa with a broad emission band and large Stokes shift from initially nonfluorescent (BA) AgBiBr (BA=CH (CH ) NH ). The emission intensity increased significantly upon further compression up to 8.2 GPa. Moreover, the band gap narrowed from the starting 2.61 eV to 2.19 eV at 25.0 GPa accompanied by a color change from light yellow to dark yellow. Analysis of combined in situ high-pressure photoluminescence, absorption, and angle-dispersive X-ray diffraction data indicates that the observed PIE can be attributed to the emission from self-trapped excitons. This coincides with [AgBr ] and [BiBr ] inter-octahedral tilting which cause a structural phase transition. High-pressure study on (BA) AgBiBr sheds light on the relationship between the structure and optical properties that may improve the material's potential applications in the fields of pressure sensing, information storage and trademark security.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/anie.201906311DOI Listing
October 2019

Highly dispersive NiCoS nanoparticles anchored on nitrogen-doped carbon nanofibers for efficient hydrogen evolution reaction.

J Colloid Interface Sci 2019 Nov 31;555:294-303. Epub 2019 Jul 31.

School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, PR China. Electronic address:

To solve the energy crisis problem, many efforts have been devoted to develop clean and sustainable alternatives to fossil fuels. Among varieties of pathways to obtain clean energy, electrochemical water splitting is a promising approach. Herein, we had successfully synthesized the [email protected] nitrogen-doped carbon nanofibers ([email protected]) nanocomposite via three successive steps consisted of in-situ oxidative polymerization, calcination, and solvothermal sulfuration reaction processes. The effect of controlled molar ratios to electrocatalytic performance was studied in detail. The optimized [email protected] nanocomposite exhibits superior electrocatalytic activity for hydrogen evolution reaction with a small overpotential of 117 mV to drive a current density of 10 mA cm. More importantly, it exhibits similar electrocatalytic activity to the initial state even after successive cyclic voltammetry scan for 3000 cycles, indicating its excellent long-term stability. The superior electrochemical performance is attributed to the developed three-dimensional (3D) network nanostructure derived from bacterial cellulose nanofibers, the highly conductive porous nitrogen-doped carbon nanofibers, and the synergistic effect between metal Ni and Co of NiCoS. This study permits a new pathway to design efficient electrocatalysts based on eco-friendly materials for the production of clean hydrogen energy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jcis.2019.07.104DOI Listing
November 2019

Significant body mass increase by oral administration of a cascade of shIL21-MSTN yeast-based DNA vaccine in mice.

Biomed Pharmacother 2019 Oct 11;118:109147. Epub 2019 Jul 11.

College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, China. Electronic address:

Base on the practical of MSTN-specific yeast-based protein vaccine in mice as described previously, this research was designed for developing a better DNA vaccine (a cascade of shIL21-MSTN yeast-based DNA vaccine) than solely MSTN yeast-based DNA vaccine to block the endogenous MSTN in the murine model. We first constructed the target vectors, including CMV-driven MSTN expression vector and a combined shIL21-MSTN vector which containing MSTN expression cassette and shIL21 (short hairpin RNA-IL21) expression cassette. After necessary validation, recombinant yeast vaccines harboring different vectors were well prepared. Subsequently, after 2-month administration, the MSTN-specific immune response was detected with western blots. The commercial ELISA assays indicated that the production of IL21 and IL6 were decreased compared with control groups. More importantly, the MSTN-specific antibody titer was much higher in the shIL21-MSTN group than MSTN group, which was consistent with the western blots result. The most important finding was significant body mass increased after oral administration of these yeast-based DNA vaccines, in which the shIL21-MSTN vaccine is slightly higher than the sole MSTN vaccine in mice. In this study, we confirmed the role of different MSTN-specific yeast-based DNA vaccines on increasing body mass in mice, to provide a good inspiration for livestock breeding through the new type of immunoregulatory method. On the other hand, we also detected the possible modulating role of shIL21 on the dendritic cell-mediated immune function which needs more practical application and deeper exploration.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.biopha.2019.109147DOI Listing
October 2019
-->