Summary
The continuing nitrogen (N) deposition observed worldwide alters ecosystem nutrient cycling and ecosystem functioning. Litter decomposition is a key process contributing to these changes, but ...the numerous mechanisms for altered decomposition remain poorly identified.
We assessed these different mechanisms with a decomposition experiment using litter from four abundant species (Achnatherum sibiricum, Agropyron cristatum, Leymus chinensis and Stipa grandis) and litter mixtures representing treatment‐specific community composition in a semi‐arid grassland under long‐term simulation of six different rates of N deposition.
Decomposition increased consistently with increasing rates of N addition in all litter types. Higher soil manganese (Mn) availability, which apparently was a consequence of N addition‐induced lower soil pH, was the most important factor for faster decomposition. Soil C : N ratios were lower with N addition that subsequently led to markedly higher bacterial to fungal ratios, which also stimulated litter decomposition.
Several factors contributed jointly to higher rates of litter decomposition in response to N deposition. Shifts in plant species composition and litter quality played a minor role compared to N‐driven reductions in soil pH and C : N, which increased soil Mn availability and altered microbial community structure. The soil‐driven effect on decomposition reported here may have long‐lasting impacts on nutrient cycling, soil organic matter dynamics and ecosystem functioning.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
A gap in emission inventories of urban volatile organic compound (VOC) sources, which contribute to regional ozone and aerosol burdens, has increased as transportation emissions in the United States ...and Europe have declined rapidly. A detailed mass balance demonstrates that the use of volatile chemical products (VCPs)-including pesticides, coatings, printing inks, adhesives, cleaning agents, and personal care products-now constitutes half of fossil fuel VOC emissions in industrialized cities. The high fraction of VCP emissions is consistent with observed urban outdoor and indoor air measurements. We show that human exposure to carbonaceous aerosols of fossil origin is transitioning away from transportation-related sources and toward VCPs. Existing U.S. regulations on VCPs emphasize mitigating ozone and air toxics, but they currently exempt many chemicals that lead to secondary organic aerosols.
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BFBNIB, NMLJ, NUK, ODKLJ, PNG, SAZU, UL, UM, UPUK
Long noncoding RNAs (lncRNAs) have important regulatory roles in cancer biology. Although some lncRNAs have well‐characterized functions, the vast majority of this class of molecules remains ...functionally uncharacterized. To systematically pinpoint functional lncRNAs, a computational approach was proposed for identification of lncRNA‐mediated competing endogenous RNAs (ceRNAs) through combining global and local regulatory direction consistency of expression. Using esophageal squamous cell carcinoma (ESCC) as model, we further identified many known and novel functional lncRNAs acting as ceRNAs (ce‐lncRNAs). We found that most of them significantly regulated the expression of cancer‐related hallmark genes. These ce‐lncRNAs were significantly regulated by enhancers, especially super‐enhancers (SEs). Landscape analyses for lncRNAs further identified SE‐associated functional ce‐lncRNAs in ESCC, such as HOTAIR, XIST, SNHG5, and LINC00094. THZ1, a specific CDK7 inhibitor, can result in global transcriptional downregulation of SE‐associated ce‐lncRNAs. We further demonstrate that a SE‐associated ce‐lncRNA, LINC00094 can be activated by transcription factors TCF3 and KLF5 through binding to SE regions and promoted ESCC cancer cell growth. THZ1 downregulated expression of LINC00094 through inhibiting TCF3 and KLF5. Our data demonstrated the important roles of SE‐associated ce‐lncRNAs in ESCC oncogenesis and might serve as targets for ESCC diagnosis and therapy.
We developed the GloceRNA method for the identification of functional ce‐lncRNAs based on merging global and local regulatory direction consistency of expression associated with ceRNAs. GloceRNA identified many known and novel functional ce‐lncRNAs, which regulated the expression of a large number of cancer hallmark genes. We further identified novel SE‐associated ce‐lncRNAs and demonstrated their important roles in ESCC.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
•The background values of ten heavy metals were determined by multiple techniques.•The estuarine sediments have a long history of Cu, Zn, Pb, Mn, and Cd contamination.•Cu, Pb, and Zn were mainly ...related to mining of the metallic ore deposits.•Pb sources changed from natural to multiple sources over time.
The concentrations of ten heavy metals (Cr, Cu, Zn, Cd, Pb, Co, Ni, Fe, Mn, and Hg) and Pb isotope compositions were investigated in two estuarine sediment cores collected in Quanzhou Bay, southeast China. The regional background levels of heavy metals in the estuarine sediments from Quanzhou Bay were established using the fine fractions (<63 μm) obtained from the sediment cores. The background values of Cr, Cu, Zn, Cd, Pb, Co, Ni, Mn, Hg, and Fe were 37.14 mg kg−1, 19.79 mg kg−1, 130.86 mg kg−1, 0.24 mg kg−1, 42.18 mg kg−1, 10.31 mg kg−1, 20.89 mg kg−1, 612.60 mg kg−1, 0.07 mg kg−1 and 3.17%, respectively. The background values of most elements (Cr, Cd, Pb, Co, Ni, Mn, Hg, and Fe) detected for the estuarine sediments from Quanzhou Bay in this study were in the middle of the obtained ranges for other locations in China. However, the Pb and Zn background values in Quanzhou Bay were significantly higher than the Chinese average. The enrichment factor (EF), geoaccumulation index (Igeo), and contamination factor (CF) values indicated that sediment contamination associated with Cu, Zn, Pb, Mn, and Cd has occurred since the nineteenth century. Based on principal component analysis (PCA) and cluster analysis (CA), Cu, Zn, and Pb were clustered into a group, and their sources could be related to the mining of metallic ore deposits. The Pb isotope composition data from the dated sediment cores further suggested that the Pb sources transitioned from natural sources during 1715–1788 CE to Pb-Zn ore deposits during 1788–1935 CE and then to multiple anthropogenic sources, including Pb-Zn ore deposits and industrial and domestic emissions, in recent decades (1935–2009 CE).
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The long non-coding RNA PVT1 (lncRNA PVT1) has been reported to act as an oncogenic regulator of several cancers. However, its expression and function in gallbladder cancer (GBC) remain largely ...unknown.
In situ hybridization (ISH) and quantitative real-time PCR (qPCR) were performed to detect the expression of PVT1 and miR-143 in GBC tissues and cell lines. Immunohistochemistry (IHC) assays were performed to assess the expression of the hexokinase 2 (HK2) protein. The relationships among PVT1, miR-143 and HK2 were evaluated using dual-luciferase reporter, RNA immunoprecipitation (RIP) and biotin pull-down assays. The biological functions of PVT1, miR-143 and HK2 in GBC cells were explored with cell counting kit 8 (CCK-8), 5-ethynyl-20-deoxyuridine (EdU), colony formation, transwell, wound healing and glucose metabolism assays in vitro. For in vivo experiments, a xenograft model was used to investigate the effects of PVT1 and HK2 on GBC.
PVT1 was upregulated in GBC tissues and cells and was positively associated with malignancies and worse overall survival. PVT1 knockdown inhibited cell proliferation, migration, and invasion in vitro and restrained tumor growth in vivo. Further studies demonstrated that PVT1 positively regulated HK2 expression via its competing endogenous RNA (ceRNA) activity on miR-143. Additionally, HK2 expression and function were positively correlated with PVT1. Furthermore, we observed that the PVT1/miR-143/HK2 axis promoted cell proliferation and metastasis by regulating aerobic glucose metabolism in GBC cells.
The results of our study reveal a potential ceRNA regulatory pathway in which PVT1 modulates HK2 expression by competitively binding to endogenous miR-143 in GBC cells, which may provide new insights into novel molecular therapeutic targets for GBC.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Chronic pain is still a basic science and clinical challenge. Unraveling of the neurobiological mechanisms involved in chronic pain will offer novel targets for the development of therapeutic ...strategies. It is well known that central sensitization in the anterior cingulate cortex (ACC) plays a critical role in initiation, development, and maintenance of chronic pain. However, the underlying mechanisms still remain elusive. Here, we reported that caveolin-1 (Cav-1), a scaffolding protein in membrane rafts, was persistently upregulated and activated in the ACC neurons after chronic constriction injury (CCI) in mice. Knockdown or blocking of Cav-1 in the contralateral ACC to the injury side reversed CCI-induced pain behavioral and neuronal sensitization and overexpression of Cav-1 in the ipsilateral ACC-induced pain behavior in the unaffected hindpaw. Furthermore, we found that Cav-1 directly binding with NMDA receptor 2B subunit (NR2B) and promotion of NR2B surface levels in the ACC contributed to modulation of chronic neuropathic pain. Disrupting the interaction of Cav-1 and NR2B through microinjection of a short peptide derived from the C-terminal of NR2B into the ACC exhibited a significant anti-nociception effect associated with decrease of surface NR2B expression. Moreover, Cav-1 increased intracellular Ca(2+) concentration and activated the ERK/CREB signaling pathway in an NR2B-dependent manner in the ACC. Our findings implicate that Cav-1 in the ACC neurons modulates chronic neuropathic pain via regulation of NR2B and subsequent activation of ERK/CREB signaling, suggesting a possible caveolin-mediated process would participate in neuronal transmission pathways implicated in pain modulation.
Objectives
To study bone healing of two‐wall bone defects after alveolar ridge preservation using mineralized dentin matrix.
Materials and Methods
After distal roots extraction of second and fourth ...premolars (P2, P4) on one lateral mandible in 12 beagles, two‐wall bone defects (5 × 5 × 5 mm) were surgically created distally to the remaining mesial roots of P2 and P4. A total of 24 sites were randomly allocated to three groups (implant material‐ time of execution): mineralized dentin matrix (MDM)‐3 m (MDM + collagen membrane; 3 months), MDM‐6 m (MDM particles + collagen membrane; 6 months), and C‐6 m (collagen membrane only; 6 months). Clinical, radiographic, digital, and histological examinations were performed 3 and 6 months after surgery.
Results
The bone healing in MDM groups were better compared to Control group (volume of bone regenerated in total: 25.12 mm3 vs. 13.30 mm3, p = .046; trabecular volume/total volume: 58.84% vs. 39.18%, p = .001; new bone formation rate: 44.13% vs. 31.88%, p = .047). Vertically, the radiological bone level of bone defect in MDM‐6 m group was higher than that in C‐6 m group (vertical height of bone defect: 1.55 mm vs. 2.74 mm, p = .018). Horizontally, no significant differences in buccolingual bone width were found between MDM and C groups at any time or at any level below the alveolar ridge. The percentages of remaining MDM were <1% in both MDM‐3 m and MDM‐6 m groups.
Conclusions
MDM improved bone healing of two‐wall bone defects and might be considered as a socket fill material used following tooth extraction.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Objectives
To evaluate the diagnostic value of computer-aided diagnosis (CAD) software on ultrasound in distinguishing benign and malignant breast masses and avoiding unnecessary biopsy.
Methods
This ...prospective, multicenter study included patients who were scheduled for pathological diagnosis of breast masses between April 2019 and November 2020. Ultrasound images, videos, CAD analysis, and BI-RADS were obtained. The AUC, accuracy, sensitivity, specificity, PPV, and NPV were calculated and compared with radiologists.
Results
Overall, 901 breast masses in 901 patients were enrolled in this study. The accuracy, sensitivity, specificity, PPV and NPV of CAD software were 89.6%, 94.2%, 87.0%, 80.4%, and 96.3, respectively, in the long-axis section; 89.0%, 91.4%, 87.7%, 80.8%, and 94.7%, respectively, in the short-axis section. With BI-RADS 4a as the cut-off value, CAD software has a higher AUC (0.906 vs 0.734 vs 0.696, all
p
< 0.001) than both experienced and less experienced radiologists. With BI-RADS 4b as the cut-off value, CAD software showed better AUC than less experienced radiologists (0.906 vs 0.874,
p
< 0.001), but not superior to experienced radiologists (0.906 vs 0.883,
p
= 0.057). After the application of CAD software, the unnecessary biopsy rate of BI-RADS categories 4 and 5 was significantly decreased (33.0% vs 11.9%, 37.8% vs 14.5%), and the malignant rate of biopsy in category 4a was significantly increased (11.6% vs 40.7%, 7.4% vs 34.9%, all
p
< 0.001).
Conclusions
CAD software on ultrasound can be used as an effective auxiliary diagnostic tool for differential diagnosis of benign and malignant breast masses and reducing unnecessary biopsy.
Clinical trial registration
ClinicalTrials.gov (NCT 03887598)
Key Points
•
Prospective multicenter study showed that computer-aided diagnosis software provides greater diagnostic confidence for differentiating benign and malignant breast masses
.
•
Computer-aided diagnosis software can help radiologists reduce unnecessary biopsy
.
•
The management of patients with breast masses becomes more appropriate
.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, VSZLJ, ZAGLJ
Tai Chi has been shown to improve motor symptoms in Parkinson's disease (PD), but its long-term effects and the related mechanisms remain to be elucidated. In this study, we investigated the effects ...of long-term Tai Chi training on motor symptoms in PD and the underlying mechanisms.
Ninety-five early-stage PD patients were enrolled and randomly divided into Tai Chi (n = 32), brisk walking (n = 31) and no-exercise (n = 32) groups. At baseline, 6 months and 12 months during one-year intervention, all participants underwent motor symptom evaluation by Berg balance scale (BBS), Unified PD rating-scale (UPDRS), Timed Up and Go test (TUG) and 3D gait analysis, functional magnetic resonance imaging (fMRI), plasma cytokine and metabolomics analysis, and blood Huntingtin interaction protein 2 (HIP2) mRNA level analysis. Longitudinal self-changes were calculated using repeated measures ANOVA. GEE (generalized estimating equations) was used to assess factors associated with the longitudinal data of rating scales. Switch rates were used for fMRI analysis. False discovery rate correction was used for multiple correction.
Participants in the Tai Chi group had better performance in BBS, UPDRS, TUG and step width. Besides, Tai Chi was advantageous over brisk walking in improving BBS and step width. The improved BBS was correlated with enhanced visual network function and downregulation of interleukin-1β. The improvements in UPDRS were associated with enhanced default mode network function, decreased L-malic acid and 3-phosphoglyceric acid, and increased adenosine and HIP2 mRNA levels. In addition, arginine biosynthesis, urea cycle, tricarboxylic acid cycle and beta oxidation of very-long-chain fatty acids were also improved by Tai Chi training.
Long-term Tai Chi training improves motor function, especially gait and balance, in PD. The underlying mechanisms may include enhanced brain network function, reduced inflammation, improved amino acid metabolism, energy metabolism and neurotransmitter metabolism, and decreased vulnerability to dopaminergic degeneration. Trial registration This study has been registered at Chinese Clinical Trial Registry (Registration number: ChiCTR2000036036; Registration date: August 22, 2020).
Abstract We explore the non-Hermitian Su–Schrieffer–Heeger model with long-range hopping and off-diagonal disorders. In the non-Hermitian clean limit, we find that the phase diagram holds topological ...semimetal phase with exceptional points except the normal insulator phase and the topological insulator phase. Interestingly, it is found that the topological semimetal phase is induced by long-range nonreciprocal term when the long-range hopping is not equal to the intercell hopping. Especially, we show the existence of topological semimetal phase with exceptional points and determine the transition point analytically and numerically under the Hermitian clean limit when the long-range hopping is equal to the intercell hopping. Furthermore, we also investigate the effects of the disorders on topological semimetal phase, and show that the disorders can enhance the region of topological semimetal phase in contrast to the case of non-Hermitian clean limit, indicating that it is beneficial to topological semimetal phase whether there is one disorder or two disorders in the system, that is, the topological semimetal phase is stable against the disorders in this one-dimensional non-Hermitian system. Our work provides an alternative avenue for studying topological semimetal phase in non-Hermitian lattice systems.
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