Publications by authors named "Peng Zhang"

6,128 Publications

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Intrahepatic paracrine signaling by CLCF1 ameliorates diet-induced NASH in mice.

Hepatology 2022 Aug 11. Epub 2022 Aug 11.

Life Sciences Institute and Department of Cell & Developmental Biology, University of Michigan Medical Center, Ann Arbor, MI, USA.

The mammalian liver harbors heterogeneous cell types that communicate via local paracrine signaling. Recent studies have delineated the transcriptomic landscape of the liver in nonalcoholic steatohepatitis (NASH) that provides insights into liver cell heterogeneity, intercellular crosstalk, and disease-associated reprogramming. However, the nature of intrahepatic signaling and its role in NASH progression remain obscure. Here we identified Cardiotrophin like cytokine factor 1 (CLCF1), a member of the IL-6 family cytokines, as a cholangiocyte-derived paracrine factor that was elevated in the liver from diet-induced NASH mice and NASH patients. AAV-mediated overexpression of CLCF1 in the liver ameliorated NASH pathologies in two diet-induced NASH models in mice, illustrating that CLCF1 induction may serve an adaptive and protective role during NASH pathogenesis. Unexpectedly, mRNA and protein levels of leukemia inhibitory factor receptor (LIFR), a subunit of the receptor complex for CLCF1, were markedly downregulated in NASH liver. Hepatocyte-specific inactivation of LIFR accelerated NASH progression in mice, supporting an important role of intrahepatic cytokine signaling in maintaining tissue homeostasis under metabolic stress conditions. Together, this study sheds light on the molecular nature of intrahepatic paracrine signaling during NASH pathogenesis and uncovers potential targets for therapeutic intervention.
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http://dx.doi.org/10.1002/hep.32719DOI Listing
August 2022

Ethnomycological study on wild mushrooms in Pu'er Prefecture, Southwest Yunnan, China.

J Ethnobiol Ethnomed 2022 Aug 10;18(1):55. Epub 2022 Aug 10.

Germplasm Bank of Wild Species, Yunnan Key Laboratory for Fungal Diversity and Green Development, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Kunming, 650201, Yunnan, People's Republic of China.

Background: Yunnan is rich in fungal diversity and cultural diversity, but there are few researches on ethnomycology. In addition, extensive utilization of wild edible fungi (WEF), especially the ectomycorrhizal fungi, threatens the fungal diversity. Hence, this study aims to contribute to the ethnomycological knowledge in Pu'er Prefecture, Yunnan, China, including information on the fungal taxa presented in markets and natural habitats, with emphasis in ectomycorrhizal fungi (EMF).

Methods: Semi-structured interviews with mushroom vendors in markets and with mushroom collectors in natural habitats were conducted. Information related to local names, habitat, fruiting time, species identification, price, cooking methods and preservation methods of wild edible mushrooms were recorded. Wild edible fungi were collected from forests, and morphological and molecular techniques were used to identify fungal species.

Results: A total of 11 markets were visited during this study. The 101 species collected in the markets belonged to 22 families and 39 genera, and about 76% of them were EMF. A wealth of ethnomycological knowledge was recorded, and we found that participants in the 45-65 age group were able to judge mushroom species more accurately. Additionally, men usually had a deepest mushroom knowledge than women. A total of 283 species, varieties and undescribed species were collected from natural habitats, and about 70% of them were EMF. Mushroom species and recorded amounts showed correspondence between markets and the natural habitats on different months.

Conclusion: The present study shows that Pu'er Prefecture is rich in local mycological knowledge and fungal diversity. However, it is necessary to continue the research of ethnomycological studies and to design and conduct dissemination of local knowledge in order to preserve it, since it currently remains mainly among the elderly population.
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http://dx.doi.org/10.1186/s13002-022-00551-7DOI Listing
August 2022

Natural colloids at environmentally relevant concentrations affect the absorption and removal of benzophenone-3 in zebrafish.

Environ Pollut 2022 Aug 7;310:119860. Epub 2022 Aug 7.

Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China.

Aquatic natural colloids are closely related to the environmental behavior of pollutants, which may affect their bioavailability in aquatic organisms. This study explored the potential mechanisms of the natural colloids at environmentally relevant concentrations affecting the bioaccumulation process of benzophenone-3 (BP3) in zebrafish (Danio rerio). The results of kinetic model fitting showed that the natural colloids decreased the uptake and loss rate of BP3 by zebrafish but prolonged the time to reach the cumulative equilibrium, eventually resulting in a higher cumulative concentration in zebrafish. According to the tissue concentration at equilibrium and the results of toxicokinetic analysis, the presence of high molecular colloids could enhance the bioaccumulation of freely dissolved BP3 due to its high desorption rate with BP3 in the intestines of fish, increasing the freely dissolved BP3 concentrations to which zebrafish were exposed. Both natural colloids and BP3 could enhance the cell permeability of zebrafish, which allowed colloid-bound BP3 to directly enter the fish and accumulate in its muscle. Besides, although both natural colloids and BP3 could cause the metabolic disorders in adult zebrafish, they affected the physiological and biochemical activities of zebrafish through different pathways. The disturbance of glutathione metabolism in zebrafish induced by natural colloids may be the reason for the diminished ability of zebrafish to clear and transform BP3 in the mixture system. The carrier effect of natural colloids and reduced clearance ability of zebrafish eventually increased the bioaccumulation of BP3 in zebrafish. This study highlights the significance of natural colloids at environmentally relevant concentrations on the biological effects of emerging contaminants in actual waters, however, natural colloids are always ignored in most field investigation of pollutants, which would ultimately lead to an underestimation of the true ecological risk of pollutants.
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http://dx.doi.org/10.1016/j.envpol.2022.119860DOI Listing
August 2022

Parthenolide modulates cerebral ischemia-induced microglial polarization and alleviates neuroinflammatory injury via the RhoA/ROCK pathway.

Phytomedicine 2022 Aug 1;105:154373. Epub 2022 Aug 1.

Institute of Basic Medical Sciences of Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing key Laboratory of pharmacology of Chinese Materia Region, Beijing 100091, PR China; NICM, Western Sydney University, Penrith, NSW 2751, Australia. Electronic address:

Background: Microglia can be activated as proinflammatory (M1) phenotypes and anti-inflammatory (M2) phenotypes after stroke. Parthenolide (PTL) has anti-inflammatory and protective effects on neurological diseases, but until now, the exact mechanisms of these processes after stroke have been unclear. The purpose of this study was to determine the effect of PTL on microglial polarization after stroke and its target for inducing microglial polarization.

Methods: Triphenyltetrazolium chloride (TTC) staining, hematoxylin-eosin (HE) staining, and neurological evaluation were performed in a focal transient cerebral ischemia rat model. The human microglia exposed to lipopolysaccharide (LPS) was used for in vitro experiments. Microglial polarization was assessed by RT-PCR and immunostaining. Inflammatory cytokine assays and western blotting were used to investigate the molecular mechanisms underlying PTL-mediated microglial polarization in vivo and in vitro.

Results: PTL significantly reduced cerebral infarction and neuronal apoptosis in rats with cerebral ischemia, reduced the level of inflammatory factors and alleviated neurological deficits. PTL treatment decreased the expression of microglia/macrophage markers in M1 macrophages and increased the expression of microglia/macrophage markers in M2 macrophages after stroke, which induced the transformation of microglia cells from the M1 phenotype to the M2 phenotype. Furthermore, PTL significantly reduced RhoA/ROCK-NF-κB pathway activity and downregulated the effects of pentanoic acid (ROCK agonist).

Conclusions: PTL has been shown to mediate neuroinflammation and protect against ischemic brain injury by regulating microglial polarization via the RhoA/ROCK pathway.
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http://dx.doi.org/10.1016/j.phymed.2022.154373DOI Listing
August 2022

Reproductive and oncological outcomes of fertility-sparing surgery in patients with stage I epithelial ovarian cancer: A systematic review and meta-analysis.

Medicine (Baltimore) 2022 Aug;101(31):e29929

Department of Gynecology and Obstetrics, West China Second Hospital, Sichuan University, Chengdu, People's Republic of China.

Objective: We meta-analyzed available evidence on fertility, survival, and cancer recurrence in patients with stage I epithelial ovarian cancer (EOC) after fertility-sparing surgery (FSS).

Methods: We systematically reviewed PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials to identify studies reporting reproductive and oncological outcomes of patients with stage I EOC who underwent FSS. Random-effects models were used to calculate pooled rates of disease outcomes, along with 95% confidence intervals (CIs). Subgroup and sensitivity analyses were conducted to identify sources of heterogeneity in the data.

Results: We included 23 observational retrospective studies involving 1126 patients. The pooled pregnancy rate was 30% (95% CI, 0.26-0.34), while the pooled natural conception rate was 26% (95% CI, 0.20-0.33). The pooled live birth rate was 27% (95% CI, 0.22-0.32). The pooled rate of EOC recurrence was 12% (95% CI, 0.09-0.14), which did not differ significantly from the rate among patients who underwent radical surgery (odds ratio, 0.77; 95% CI, 0.45-1.33).

Conclusions: FSS is associated with good oncological outcomes but less than satisfactory reproductive outcomes. All in all, the procedure appears to be a safe alternative to radical surgery for EOC patients who want to preserve fertility.
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http://dx.doi.org/10.1097/MD.0000000000029929DOI Listing
August 2022

Thymectomy in ocular myasthenia gravis-prognosis and risk factors analysis.

Orphanet J Rare Dis 2022 Aug 9;17(1):309. Epub 2022 Aug 9.

Department of Cardiothoracic Surgery, Tianjin Medical University General Hospital, No.154, Anshan Road, Tianjin, China.

Background: Several retrospective studies have identified risk factors associated with ocular myasthenia gravis (OMG) generalization in non-surgical patients. However, the outcomes of OMG after thymectomy have not been investigated fully. This study aimed to explore the clinical predictors of post-thymectomy OMG prognosis.

Methods: We performed a retrospective review of OMG patients who underwent thymectomy at our institution from January 2012 to December 2021. Kaplan-Meier and Cox proportional hazard regression analyses were used to evaluate associations between clinical features and prognosis. The main outcome measures were OMG conversion, complete stable remission (CSR), and clinical improvement.

Results: Fifty-eight patients were identified for conversion analysis. Thirteen (22.4%) developed generalized myasthenia gravis (GMG) at a median time of 12.7 (3-37.3) months from symptom onset. Repetitive nerve stimulation (RNS)-positivity was associated with increased risk of conversion to GMG (P = 0.002). Patients with histotype B2/B3 thymoma showed a higher risk of conversion (P = 0.002) than did patients with hyperplasia and AB/B1 thymoma. Fifty-two patients fulfilled the criteria for CSR and improvement. Sixteen (30.8%) achieved CSR at a median time of 28.7 (15-54) months after thymectomy. Fifteen (28.8%) showed clinical improvement at last follow up. Patients who achieved CSR showed a younger age of onset (P = 0.022), lower percentage of acetylcholine receptor antibody-seropositivity (P = 0.029). Histologically, patients with thymic hyperplasia and stage I thymoma showed a higher chance of CSR (P = 0.010) than did patients with stage II/III thymoma. Multivariate analysis revealed that RNS-positivity (hazard ratio [HR] 6.007, P = 0.021) and histotype B2/B3 thymoma (HR 4.611, P = 0.048) were associated with OMG conversion. Thymic hyperplasia and stage I thymoma (HR 0.300, P = 0.026) were associated with OMG CSR after thymectomy.

Conclusion: For OMG patients after thymectomy, RNS-positivity and histotype B2/B3 thymoma are independent predictors of conversion to GMG. On the other hand, thymic hyperplasia and stage I thymoma independently predict CSR.
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http://dx.doi.org/10.1186/s13023-022-02454-yDOI Listing
August 2022

A powerful tool for near-infrared spectroscopy: Synergy adaptive moving window algorithm based on the immune support vector machine.

Spectrochim Acta A Mol Biomol Spectrosc 2022 Jul 14;282:121631. Epub 2022 Jul 14.

School of Political Science and Law, Zhongyuan University of Technology, Zhengzhou, China.

Traditional trial-and-error methods are time-consuming and inefficient, especially very unfriendly to inexperienced analysts, and are sometimes still used to select preprocessing methods or wavelength variables in near-infrared spectroscopy (NIR). To deal with this problem, a new optimization algorithm called synergy adaptive moving window algorithm based on the immune support vector machine (SA-MW-ISVM) is proposed in this paper. Following the principle of SA-MW-ISVM, the original problem of calibration model optimization is transformed into a mathematical optimization problem that can be processed by the proposed immune support vector machine regression algorithm. The main objective of this optimization problem is the calibration model performance; meanwhile, the constraint conditions include a reasonable spectral data value, spectral data preprocessing method, and calibration model parameters. A unique antibody structure and specific coding and decoding method are used to achieve collaborative optimization in NIR spectroscopy. The tests on four actual near-infrared datasets, including a group of gasoline and three groups of diesel fuels, have shown that the proposed SA-MW-ISVM algorithm can significantly improve the calibration performance and thus achieve accurate prediction results. In the case of gasoline, the SA-MW-ISVM algorithm can decrease the prediction error by 44.09% compared with the common benchmark partial least square (PLS). Meanwhile, in the case of diesel fuels, the SA-MW-ISVM algorithm can decrease the prediction error of cetane number, freezing temperature, and viscosity by 9.99%, 28.69%, and 43.85%, respectively, compared with the PLS. The powerful prediction performance of the SA-MW-ISVM algorithm makes it an ideal tool for modeling near-infrared spectral data or other related application fields.
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http://dx.doi.org/10.1016/j.saa.2022.121631DOI Listing
July 2022

Time course of beat-to-beat blood pressure variability and outcome in patients with spontaneous intracerebral haemorrhage.

J Hypertens 2022 Sep 22;40(9):1744-1750. Epub 2022 Jul 22.

Stroke Center, Department of Neurology, the First Hospital of Jilin University.

Objectives: Increased blood pressure variability (BPV) over 24 h or longer was associated with poor clinical outcomes in patients with intracerebral haemorrhage (ICH). However, the characteristics of beat-to-beat BPV, a rapid assessment of BPV and its association with outcome in ICH patients remain unknown.

Methods: We consecutively and prospectively recruited patients with ICH between June 2014 and December 2020. Five-minute noninvasive beat-to-beat recordings were measured serially at three time points, 1-2, 4-6 and 10-12 days after ICH onset. BPV was calculated using standard deviation (SD) and variation independent of mean (VIM). Favourable outcome was defined as modified Rankin Scale score of less than 2 at 90 days.

Results: The analysis included 66 participants (54.12 ± 10.79 years; 71.2% men) and 66 age and sex-matched healthy controls. Compared with that in healthy adults, beat-to-beat BPV was significantly increased 1-2 days after ICH and was completely recovered 10-12 days later. BPV recorded 1-2 days after ICH onset was higher among patients with unfavourable outcomes than among those with favourable outcomes (all P < 0.05) and higher BPV on days 1-2 was independently associated with a 3-month unfavourable outcome after adjustment for major covariates.

Conclusion: Beat-to-beat BPV was significantly increased among patients with ICH and could be completely recovered 10-12 days later. In addition, beat-to-beat BPV 1-2 days after ICH was independently associated with prognosis and could be regarded as a potential prognostic predictor and effective therapeutic target in the future.
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http://dx.doi.org/10.1097/HJH.0000000000003206DOI Listing
September 2022

Novel dual-reference approach facilitates the activation mapping and catheter ablation of premature atrial complexes with non-pulmonary vein and non-superior vena cava origins.

Europace 2022 Aug 9. Epub 2022 Aug 9.

Department of Cardiology, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, 1665 Kongjiang Road, 200092 Shanghai, China.

Aims: Activation mapping of premature atrial complexes (PACs) proves challenging due to interference by mechanical bumping and non-targeted ectopies. This study aims to compare the mapping efficacy, instant success, and long-term recurrence of catheter ablation for PACs with non-pulmonary vein (PV) and non-superior vena cava (SVC) origins between the novel dual-reference approach (DRA) and the routine single-reference approach (SRA) of mapping.

Methods And Results: Patients with symptomatic, drug-refractory PACs, or frequent residual PACs after atrial tachyarrhythmia ablation were enrolled. During activation mapping, the coronary sinus (CS) catheter was used as the only timing reference in the SRA group. In the DRA group, another catheter, which was spatially separated from the CS catheter, was used as the second reference. The timing difference between the two references was used to discriminate the targeted PACs from the uninterested rhythms. Procedural parameters and long-term recurrence were compared. A total of 188 patients (109 in SRA and 79 in DRA) were enrolled. The baseline characteristics were similar. Compared with the SRA group, the DRA group had less repeated mapping (1.2 ± 0.4 vs. 1.4 ± 0.5, P = 0.004), shorter mapping (15 ± 6 vs. 23 ± 7 min, P < 0.001) and procedural time (119 ± 28 vs. 132 ± 22 min, P = 0.001), similar procedural complication rates (3.6 vs. 3.8%, P > 0.999), higher instant success (96.2 vs. 87.2%, P = 0.039), and lower recurrence rate (15.2 vs. 29.3%, hazard ratio 1.943, P = 0.033) during a 24-month follow-up.

Conclusion: As a novel strategy, the DRA shortens the procedural time and improves both instant and long-term success of PAC ablation, serving as a promising approach in mapping PACs with non-PV and non-SVC origins.
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http://dx.doi.org/10.1093/europace/euac129DOI Listing
August 2022

Role of Autophagy Inducers and Inhibitors in Intestinal Barrier Injury Induced by Intestinal Ischemia-Reperfusion (I/R).

J Immunol Res 2022 30;2022:9822157. Epub 2022 Jul 30.

Department of General Surgery, The First People's Hospital of Yunnan Province, The Affiliated Hospital of Kunming University of Science and Technology, Kunming, 650032 Yunnan Province, China.

Objectives: Intestinal epithelial barrier function is an important mechanical barrier to maintain intestinal homeostasis and resist the invasion of intestinal pathogens and microorganisms. However, intestinal epithelial barrier function is vulnerable to damage under intestinal ischemia-reperfusion (I/R) injury. Under a category of pathophysiological conditions, including I/R, autophagy plays a crucial role. This study is aimed at discussing the role of autophagy inhibitors and activators in intestinal epithelial barrier function after intestinal I/R by changing autophagy levels.

Methods: Mice with intestinal IR underwent 45 minutes of surgery for superior mesenteric artery occlusion. The autophagy inhibitor 3-MA and the autophagy inducer rapamycin (RAP) were used to change the level of autophagy, and then, the expressions of tight junction proteins and intestinal barrier function were detected.

Results: The results showed that the autophagy inhibitor 3-MA aggravated intestinal epithelial barrier dysfunction, while the autophagy inducer RAP attenuated intestinal epithelial barrier dysfunction. In addition, promoting autophagy may promote occludin expression by inhibiting claudin-2 expression.

Conclusion: Upregulation of autophagy levels by autophagy inducers can enhance intestinal epithelial barrier function after intestinal I/R.
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http://dx.doi.org/10.1155/2022/9822157DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9356893PMC
August 2022

Prior Attention Network for Multi-Lesion Segmentation in Medical Images.

IEEE Trans Med Imaging 2022 Aug 8;PP. Epub 2022 Aug 8.

The accurate segmentation of multiple types of lesions from adjacent tissues in medical images is significant in clinical practice. Convolutional neural networks (CNNs) based on the coarse-to-fine strategy have been widely used in this field. However, multi-lesion segmentation remains to be challenging due to the uncertainty in size, contrast, and high interclass similarity of tissues. In addition, the commonly adopted cascaded strategy is rather demanding in terms of hardware, which limits the potential of clinical deployment. To address the problems above, we propose a novel Prior Attention Network (PANet) that follows the coarse-to-fine strategy to perform multi-lesion segmentation in medical images. The proposed network achieves the two steps of segmentation in a single network by inserting a lesion-related spatial attention mechanism in the network. Further, we also propose the intermediate supervision strategy for generating lesion-related attention to acquire the regions of interest (ROIs), which accelerates the convergence and obviously improves the segmentation performance. We have investigated the proposed segmentation framework in two applications: 2D segmentation of multiple lung infections in lung CT slices and 3D segmentation of multiple lesions in brain MRIs. Experimental results show that in both 2D and 3D segmentation tasks our proposed network achieves better performance with less computational cost compared with cascaded networks. The proposed network can be regarded as a universal solution to multi-lesion segmentation in both 2D and 3D tasks. The source code is available at https: //github.com/hsiangyuzhao/PANet.
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http://dx.doi.org/10.1109/TMI.2022.3197180DOI Listing
August 2022

Higher Harmonics in Multipactor Induced Plasma Ionization Breakdown near a Dielectric Surface.

Phys Rev Lett 2022 Jul;129(4):045001

Department of Electrical and Computer Engineering, Michigan State University, East Lansing, Michigan 48824, USA.

In this Letter, the novel physics of higher harmonic (HH) generation of the normal electric field near a dielectric surface is reported in multipactor induced plasma ionization breakdown, as determined by kinetic particle-in-cell simulations. The observed HH frequency is around ten times the fundamental rf driving frequency, but lower than the electron plasma frequency. A theory is constructed which indicates that stream plasma interaction-induced instability is the mechanism of HH generation in the collisional regime. The HH frequency and its corresponding growth rate of the HH oscillation amplitude from the theory are in good agreement with kinetic particle-in-cell simulations.
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http://dx.doi.org/10.1103/PhysRevLett.129.045001DOI Listing
July 2022

Significant Contribution of Solid Organic Matter for Hydroxyl Radical Production during Oxygenation.

Environ Sci Technol 2022 Aug 7. Epub 2022 Aug 7.

State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, No. 68 Jincheng Street, East Lake High-Tech Development Zone, Wuhan 430078, P. R. China.

Dark formation of hydroxyl radicals (•OH) from soil/sediment oxygenation has been increasingly reported, and solid Fe(II) is considered as the main electron donor for O activation. However, the role of solid organic matter (SOM) in •OH production is not clear, although it represents an important electron pool in the subsurface. In this study, •OH production from oxygenation of reduced solid humic acid (HA) was investigated at pH 7.0. •OH production is linearly correlated with the electrons released from HA suspension. Solid HA transferred electrons rapidly to O via the surface-reduced moieties (hydroquinone groups), which was fueled by the slow electron transfer from the reduced moieties inside solid HA. Cycling of dissolved HA between oxidized and reduced states could mediate the electron transfer from solid HA to O for •OH production enhancement. Modeling results predicted that reduced SOM played an important or even dominant role in •OH production for the soils and sediments possessing high molar ratios of SOC/Fe(II) (e.g., >39). The significant contribution of SOM was further validated by the modeling results for oxygenation of 88 soils/sediments in the literature. Therefore, reduced SOM should be considered carefully to comprehensively understand •OH production in SOM-rich subsurface environments.
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http://dx.doi.org/10.1021/acs.est.2c02766DOI Listing
August 2022

Early evaluation of adjuvant effects on topramezone efficacy under different temperature conditions using chlorophyll fluorescence tests.

Front Plant Sci 2022 22;13:920902. Epub 2022 Jul 22.

Institute of Plant Protection, Beijing Academy of Agriculture and Forestry Sciences, Beijing, China.

Proper selection of adjuvant applications is an important strategy to enhance herbicide efficacy and reduce active ingredient input especially under adverse environmental conditions. In this study, a two-factor split-plot-design experiment was conducted to evaluate the effects of two adjuvants on the efficacy of topramezone on the grassy weed species giant foxtail ( Herrm.) and the broadleaved weed species velvetleaf ( Medik.) under three different temperature conditions. The two tested adjuvants were methylated seed oil (MSO) and organosilicone. Three temperature levels, 35/30°C, 25/20°C, and 15/10°C (day/night), were used in the laboratory and greenhouse experiment. Plant chlorophyll fluorescence measurements shortly after herbicide application and classic whole-plant bioassay methods were used to evaluate the herbicide efficacy among the different treatments. Results indicated that the maximum quantum efficiency (Fv/Fm) of the top leaf of the weeds treated with topramezone mixed with MSO was significantly lower than that of the weeds treated with topramezone mixed with organosilicone and without an adjuvant at 2-3 days after treatment under all three temperature levels. The herbicide response of the plants treated with topramezone mixed with organosilicone and topramezone alone was not significantly different. These results corresponded well with the results of the classic whole-plant test. MSO has been shown to be good at enhancing the efficacy of topramezone on these weed species under all three temperature conditions. The measurement of chlorophyll fluorescence is a promising technique for evaluating the effects of adjuvants on the efficacy of herbicides shortly after herbicide treatment.
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http://dx.doi.org/10.3389/fpls.2022.920902DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9355585PMC
July 2022

Function of Internal and External Fe in a Ni-Based Precatalyst System Toward Oxygen Evolution Reaction.

Inorg Chem 2022 Aug 5. Epub 2022 Aug 5.

College of Chemistry & Chemical Engineering, Yangzhou University, Yangzhou 225002, P. R. China.

It is well known that the "iron" impurity will influence the oxygen evolution reaction (OER) in an alkaline electrolyte, especially for the Ni-based electrocatalyst. Many research studies have investigated the function of Fe in the OER active phase, such as (OH)/OOH ( = Ni and/or Fe), while, surprisingly, very few studies have examined the function of Fe in the "precatalyst" system. Accordingly, in this work, the NiFeP ( = 0, 0.5, 1) series as an Ni-based precatalyst was employed to inspect the function of internal and external Fe in the Ni-based precatalyst system. It was realized that the sample with internal Fe (i.e., NiFeP and NiFeP) exhibits efficient OER activity compared to that of the Fe-free one (i.e., NiP) owing to the large amount of active (OH)/OOH formed on the surface. This indicates that the internal Fe in the present system may have the ability to facilitate the phase transformation; it was later rationalized from electronic structural calculations that the d band center of the internal Fe (middle transition metal) and Ni (late transition metal) holds the key for this observation. Adding excessive ferrous chloride tetrahydrate (FeCl·4HO) as the external Fe in the electrolyte will greatly improve the OER performances for NiP; nevertheless, that the OER activity of NiFeP is still much superior than that of NiP corroborates the fact that the Fe impurity is not the only reason for the elevated OER activity of NiFeP and that internal Fe is also critical to the phase transformation as well as OER performance.
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http://dx.doi.org/10.1021/acs.inorgchem.2c01867DOI Listing
August 2022

Natural Phenylethanoid Supplementation Alleviates Metabolic Syndrome in Female Mice Induced by High-Fructose Diet.

Front Pharmacol 2022 19;13:850777. Epub 2022 Jul 19.

State Key Laboratory of Component-Based Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin, China.

Tyrosol (T), hydroxytyrosol (H), and salidroside (S) are typical phenylethanoids and also powerful dietary antioxidants. This study aimed at evaluating the influence of three natural phenylethanoids, which are dietary phenylethanoids of natural origins, on reversing gut dysbiosis and attenuating nonalcoholic fatty liver features of the liver induced by metabolic syndrome (MetS) mice. C57BL/6J female mice induced with high-fructose diet were established and administrated with salidroside, tyrosol, and hydroxytyrosol for 12 weeks, respectively. Biochemical analysis showed that S, T, and H significantly improved glucose metabolism and lipid metabolism, including reduced levels of total cholesterol insulin (INS), uric acid, low-density lipoprotein cholesterol (LDL-C), and aspartate aminotransferase (ALT). Histopathological observation of the liver confirmed the protective effects of S, T, and H against hepatic steatosis, which were demonstrated by the results of metabolomic analysis, such as the improvement in glycolysis, purine metabolism, bile acid, fatty acid metabolism, and choline metabolism. Additionally, 16S rRNA gene sequence data revealed that S, T, and H could enhance the diversity of gut microbiota. These findings suggested that S, T, and H probably suppress lipid accumulation and have hepatoprotective effects and improve intestinal microflora disorders to attenuate metabolic syndromes.
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http://dx.doi.org/10.3389/fphar.2022.850777DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9343882PMC
July 2022

Adaptive permissible region based random Kaczmarz reconstruction method for localization of carotid atherosclerotic plaques in fluorescence molecular tomography.

Phys Med Biol 2022 Aug 4. Epub 2022 Aug 4.

CAS Key Laboratory of Molecular Imaging, Institute of Automation, Chinese Academy of Sciences, 95 Zhongguancun East Road, Beijing, Beijing, 100190, CHINA.

Objective: In this study, we propose the adaptive permissible region based random Kaczmarz method as an improved reconstruction method to recover small carotid atherosclerotic plaque targets in rodents with high resolution in fluorescence molecular tomography (FMT).

Approach: We introduce the random Kaczmarz method as an advanced minimization method to solve the FMT inverse problem. To satisfy the special condition of this method, we proposed an adaptive permissible region strategy based on traditional permissible region methods to flexibly compress the dimension of the solution space.

Main Results: Monte Carlo simulations, phantom experiments, and in vivo experiments demonstrate that the proposed method can recover the small carotid atherosclerotic plaque targets with high resolution and accuracy, and can achieve lower root mean squared error and distance error (DE) than other traditional methods. For targets with 1.5 mm diameter and 0.5 mm separation, the DE indicators can be improved by up to 40%. Moreover, the proposed method can be utilized for in vivo locating atherosclerotic plaques with high accuracy and robustness.

Significance: We applied the random Kaczmarz method to solve the inverse problem in FMT and improve the reconstruction result via this advanced minimization method. We verified that the FMT technology has a great potential to locate and quantify atherosclerotic plaques with higher accuracy, and can be expanded to more preclinical research.
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http://dx.doi.org/10.1088/1361-6560/ac8718DOI Listing
August 2022

Self-Adhesive Hydrogel Biomimetic Periosteum to Promote Critical-Size Bone Defect Repair via Synergistic Osteogenesis and Angiogenesis.

ACS Appl Mater Interfaces 2022 Aug 4. Epub 2022 Aug 4.

School of Materials Science and Engineering, South China University of Technology, Guangzhou 510641, China.

The periosteum plays an important role in the regeneration of critical-size bone defects, with functions of recruiting multiple cells, accelerating vascular network reconstruction, and guiding bone tissue regeneration. However, these functions cannot be easily implemented by simply simulating the periosteum via a material structure design or by loading exogenous cytokines. Herein, inspired by the periosteal function, we propose a biomimetic periosteum preparation strategy to enhance natural polymer hydrogel membranes using inorganic bioactive materials. The biomimetic periosteum having bone tissue self-adhesive functions and resembling an extracellular matrix was prepared using dopamine-modified gelatin and oxidized hyaluronan (GA/HA), and micro/nanobioactive glass (MNBG) was further incorporated into the hydrogel to fabricate an organic/inorganic co-crosslinked hydrogel membrane (GA/HA-BG). The addition of MNBG enhanced the stability of the natural polymer hydrogel membrane, resulting in a sustained degradation time, biomineralization, and long-term release of ions. The Ca and SiO ions released by bioactive glass were shown to recruit cells and promote the differentiation of bone marrow stromal cells into osteoblasts, initiating multicentric osteogenic behavior. Additionally, the bioactive ions were able to continuously stimulate the endogenous expression of vascular endothelial growth factor from human umbilical vein endothelial cells through the PI3K/Akt/HIF-1α pathway, which accelerated vascularization of the defect area and synergistically promoted the repair of bone defects. This organic-inorganic biomimetic periosteum has been proved to be effective and versatile in critical-size bone defect repair and is expected to provide a promising strategy for solving clinical issues.
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http://dx.doi.org/10.1021/acsami.2c08400DOI Listing
August 2022

CD24-Siglec axis is an innate immune checkpoint against metaflammation and metabolic disorder.

Cell Metab 2022 Aug;34(8):1088-1103.e6

Division of Immunotherapy, Institute of Human Virology and Department of Surgery, University of Maryland School of Medicine, Baltimore, MD 21201, USA; OncoImmune, Inc., Rockville, MD 20850, USA; OncoC4, Inc., Rockville, MD 20850, USA. Electronic address:

The molecular interactions that regulate chronic inflammation underlying metabolic disease remain largely unknown. Since the CD24-Siglec interaction regulates inflammatory response to danger-associated molecular patterns (DAMPs), we have generated multiple mouse strains with single or combined mutations of Cd24 or Siglec genes to explore the role of the CD24-Siglec interaction in metaflammation and metabolic disorder. Here, we report that the CD24-Siglec-E axis, but not other Siglecs, is a key suppressor of obesity-related metabolic dysfunction. Inactivation of the CD24-Siglec-E pathway exacerbates, while CD24Fc treatment alleviates, diet-induced metabolic disorders, including obesity, dyslipidemia, insulin resistance, and nonalcoholic steatohepatitis (NASH). Mechanistically, sialylation-dependent recognition of CD24 by Siglec-E induces SHP-1 recruitment and represses metaflammation to protect against metabolic syndrome. A first-in-human study of CD24Fc (NCT02650895) supports the significance of this pathway in human lipid metabolism and inflammation. These findings identify the CD24-Siglec-E axis as an innate immune checkpoint against metaflammation and metabolic disorder and suggest a promising therapeutic target for metabolic disease.
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http://dx.doi.org/10.1016/j.cmet.2022.07.005DOI Listing
August 2022

Molecular and structural characterization of a promiscuous chalcone synthase from the fern species Stenoloma chusanum.

J Integr Plant Biol 2022 Aug 3. Epub 2022 Aug 3.

Key Laboratory of Chemical Biology of Natural Products, Ministry of Education, School of Pharmaceutical Sciences, Shandong University, Jinan, 250100, China.

The key enzymes involved in the flavonoid biosynthesis pathway have been extensively studied in seed plants, but relatively less in ferns. In this study, two 4-Coumarate: coenzyme A ligases (Sc4CL1 and Sc4CL2) and one novel chalcone synthase (ScCHS1) were functionally characterized by mining the Stenoloma chusanum transcriptome database. Recombinant Sc4CLs were able to esterify various hydroxycinnamic acids to corresponding acyl-coenzyme A (CoA). ScCHS1 could catalyze p-coumaroyl-CoA, cinnamoyl-CoA, caffeoyl-CoA, and feruloyl-CoA to form naringenin, pinocembrin, eriodictyol, and homoeriodictyol, respectively. Moreover, enzymatic kinetics studies revealed that the optimal substrates of ScCHS1 were feruloyl-CoA and caffeoyl-CoA, rather than p-coumaroyl-CoA, which was substantially different from the common CHSs. Crystallographic and site-directed mutagenesis experiments indicated that the amino acid residues, Leu87, Leu97, Met165, and Ile200, located in the substrate-binding pocket near the B-ring of products, could exert a significant impact on the unique catalytic activity of ScCHS1. Furthermore, overexpression of ScCHS1 in tt4 mutants could partially rescue the mutant phenotypes. Finally, ScCHS1 and Sc4CL1 were used to synthesize flavanones and flavones with multi-substituted hydroxyl and methoxyl B-ring in Escherichia coli, which can effectively eliminate the need for the cytochrome P450 hydroxylation/O-methyltransferase from simple phenylpropanoid acids. In summary, the identification of these important Stenoloma enzymes provides a springboard for the future production of various flavonoids in E. coli. This article is protected by copyright. All rights reserved.
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http://dx.doi.org/10.1111/jipb.13335DOI Listing
August 2022

A Combination of Preoperative Computed Tomography-Defined Sarcopenia and Systemic Inflammation on Survival in Patients with Poorly Differentiated Neuroendocrine Neoplasms Following Radical Resection.

Nutr Cancer 2022 Aug 3:1-11. Epub 2022 Aug 3.

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

This retrospective study of 122 patients with gastrointestinal poorly differentiated neuroendocrine neoplasms (GI-PDNEN) who underwent radical resection between January 2010 and December 2020 aimed to investigate the usefulness of combined computed tomography (CT)-defined sarcopenia and systemic inflammation to evaluate long-term prognoses for patients who underwent radical surgical resection. Sarcopenia, based on a pre-defined L3 skeletal muscle index cutoff value, was assessed using preoperative abdominal CT images. Patients (neuroendocrine carcinoma, 86 patients; mixed adenoneuroendocrine carcinoma, 36 patients) were divided into low-, intermediate-, and high-risk groups using sarcopenia scores and neutrophil-to-lymphocyte ratios (SNLRs). Higher SNLRs were significantly associated with higher age ( = 0.004), larger tumor size ( = 0.042), lower body mass index ( = 0.042), and lower hemoglobin ( = 0.001) and albumin ( = 0.031) levels. Multivariate analysis indicated that a higher SNLR was an independent risk factor for poor overall survival (OS,  = 0.01) and relapse-free survival (RFS,  = 0.001) in patients with GI-PDNEN postoperatively. Sarcopenia and a higher NLR were significantly associated with poor RFS and OS following radical resection. The SNLR had a definite predictive prognostic value in preoperatively identifying patients with GI-PDNEN and a probable poor long-term prognosis, especially those with neuroendocrine carcinoma.
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http://dx.doi.org/10.1080/01635581.2022.2102660DOI Listing
August 2022

Enhanced bone regeneration PHA scaffolds coated with polydopamine-captured BMP2.

J Mater Chem B 2022 Aug 3. Epub 2022 Aug 3.

Key Laboratory of Industrial Biocatalysis, Ministry of Education, Department of Chemical Engineering, Tsinghua University, Tsinghua-Peking Center of Life Sciences, Beijing 100084, China.

The hierarchical three-dimensional (3D)-printing scaffolds based on microbial polyester poly(3-hydroxybutyrate--4-hydroxybutyrate) (P34HB) were designed and used for bone tissue engineering surface functionalization on 3D-printed (P34HB) scaffolds using polydopamine (PDA)-mediated recombinant human bone morphogenetic protein-2 (BMP2), leading to enhanced bone formation in a rat model with a calvarial critical-size bone defect. Taking advantage of the adhesive property of PDA under alkaline and aerobic conditions, osteogenic BMP2 was captured on the surface of PHA scaffolds, resulting in their enhanced osteogenic bioactivity, better stem cell adhesion and proliferation, and sustainable release of a bioactive substance over a period of 30 days. These contributed to notable differences in alkaline phosphatase (ALP) activity, mineralization, expressions of osteogenesis-related genes, as well as finally enhanced bone formation in rats. The functionalized 3D-printed P34HB scaffolds the PDA-mediated osteogenic activity were developed as a versatile platform for bone tissue regeneration.
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http://dx.doi.org/10.1039/d2tb01122kDOI Listing
August 2022

The effect of specific adsorption of halide ions on electrochemical CO reduction.

Chem Sci 2022 Jul 28;13(27):8117-8123. Epub 2022 Jun 28.

School of Chemical Engineering and Technology, Key Laboratory for Green Chemical Technology of Ministry of Education, Tianjin University Tianjin 300072 China

In the electrochemical CO reduction reaction (CORR), halide ions could impose a significant effect on multi-carbon (C) product production for Cu-based catalysts by a combined contribution from various mechanisms. However, the nature of specific adsorption of halide ions remains elusive due to the difficulty in decoupling different effects. This paper describes a facile method to actively immobilize the morphology of Cu-based catalysts during the CORR, which makes it possible to reveal the fundamental mechanism of specific adsorption of halide ions. A stable morphology is obtained by pre-reduction in aqueous KX (X = Cl, Br, I) electrolytes followed by conducting the CORR using non-buffered and non-specifically adsorbed KSO as the supporting electrolyte, by which the change of local pH and cation concentration is also maintained during the CORR. spectroscopy revealed that the specific adsorption of halide ions enhances the adsorption of *CO intermediates, which enables a high selectivity of 84.5% for C products in 1.0 M KI.
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http://dx.doi.org/10.1039/d2sc02689aDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9278460PMC
July 2022

1D and 3D co-simulation and self-adaptive position control of electrostatic levitation in China's Space Station.

NPJ Microgravity 2022 Aug 2;8(1):29. Epub 2022 Aug 2.

State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, China Academy of Sciences, Shanghai, China.

The greatest challenge of electrostatic levitation for containerless material processing is the stable control of charged material during heating. Recently, high-precision self-adaptive control of electrostatic levitation has been achieved in China's Space Station. Based on the 1D and 3D co-simulation analysis, an optimal scheduling of control strategies of sample release and retrieval in space is developed. Both simulation results and on-orbit experiments demonstrated that the inversion of surface charge is responsible for the heating induced material instability. On-orbit experiments indicated that under laser illuminations, the net surface charge of metal Zr changed from positive to negative at 900 K and from negative to positive at 1300 K. The possible physical mechanism of the charge inversion of heated material is discussed.
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http://dx.doi.org/10.1038/s41526-022-00215-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9345915PMC
August 2022

Gemcitabine Plus Anlotinib Is Effective and Safe Compared to Gemcitabine Plus Docetaxel in Advanced Soft Tissue Sarcoma.

Front Oncol 2022 13;12:922127. Epub 2022 Jul 13.

Department of Orthopedics, The Affiliated Cancer Hospital of Zhengzhou University and Henan Cancer Hospital, Zhengzhou, China.

Objective: The aim of this study is to compare gemcitabine (G) plus docetaxel (D) versus G plus anlotinib (A) for advanced soft tissue sarcoma (STS).

Methods: We retrospectively investigated 122 patients with locally advanced or metastatic STS who were treated with either G+D or G+A between July 2016 and October 2021 and compared the efficacy and toxicity of G+D and G+A. The primary endpoints were median progression-free survival (PFS) and the proportion of patients with grade ≥3 adverse events. We also analyzed differences in the clinical efficacy of G+D and G+A in leiomyosarcoma, and the differences in the clinical efficacy of G+D and G+A as first-line therapy.

Results: Overall, 122 patients were included (81 patients receiving G+D and 41 patients receiving G+A) with a median age of 55 years. The main histological types are leiomyosarcoma, undifferentiated pleomorphic sarcoma, and liposarcoma. After a median follow-up of 25 months, PFS did not differ between patients treated with G+D and those treated with G+A (median PFS: 5.8 months and 6.8 months, = 0.39), and overall survival (OS) was similar (median OS: 14.7 vs. 13.3 months, = 0.75) with a similar objective response rate (18.5% vs. 14.6%, = 0.17), whereas the proportion of patients with grade ≥3 adverse events treated with G+D was significantly higher than those treated with G+A (68% vs. 44%, < 0.05). Subgroup analysis of leiomyosarcoma patients (47.5% of the patients) and first-line treatment patients (46.7% of the patients) shows that PFS was not significantly different between the two groups (LMS: median PFS: 6.5 months vs. 7.5 months, = 0.08; first-line treatment: median PFS: 6.2 months vs. 7.1 months, = 0.51).

Conclusion: Compared with gemcitabine plus docetaxel for advanced STS, gemcitabine plus anlotinib achieved a similar response rate on median PFS and OS, but lower toxicity. These results suggest that gemcitabine plus anlotinib may be an effective and safe strategy for advanced STS.
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http://dx.doi.org/10.3389/fonc.2022.922127DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9326030PMC
July 2022

Comparison of Affected-Vertebra Fixation of Cortical Bone Trajectory Screw and Pedicle Screw for Lumbar Tuberculosis: A Minimum 3-Year Follow-Up.

Biomed Res Int 2022 21;2022:6312994. Epub 2022 Jul 21.

Affiliated Hangzhou Chest Hospital, Zhejiang University School of Medicine, Hangzhou, China.

Purpose: This study is aimed at comparing the clinical efficacy of cortical bone trajectory (CBT) screw fixation and pedicle screw (PS) fixation of the affected vertebrae in lumbar tuberculosis.

Methods: We retrospectively analyzed the outcomes in 52 patients (27 cases in the CBT group, 25 cases in the PS group) with lumbar TB who underwent posterior affected-vertebra fixation combined with anterior debridement and bone grafting. The intraoperative blood loss, operative time, visual analog scale (VAS) scores for incision pain and leg pain, Japanese Orthopedic Association (JOA) score, bone grafting fusion, and complications were recorded.

Results: All patients were followed up for 35-52 months and achieved good clinical outcomes. There were no differences between the two groups in the operative time, intraoperative blood loss, JOA score, bone grafting fusion, and complications. However, there was a significant difference between the two groups in VAS scores for incision pain on the 1st day and 3rd day after surgery. At the last follow-up, JOA scores were significantly improved in both groups compared to the preoperation.

Conclusion: This retrospective study confirmed that both the affected-vertebra CBT screw fixation and PS fixation for lumbar TB via posterior and anterior approaches could achieve satisfactory outcomes, while the former resulted in better improvement for postoperative VAS scores.
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http://dx.doi.org/10.1155/2022/6312994DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9334104PMC
August 2022

Alzheimer's disease diagnosis via multimodal feature fusion.

Comput Biol Med 2022 Jul 20;148:105901. Epub 2022 Jul 20.

School of Computer Science and Engineering, Northeastern University, Shenyang, China.

Alzheimer's disease (AD) is the most common neurodegenerative disorder in the elderly. Early diagnosis of AD plays a vital role in slowing down the progress of AD because there is no effective drug to treat the disease. Some deep learning models have recently been presented for AD diagnosis and have more satisfactory performance than classic machine learning methods. Nevertheless, most of the existing computer-aided diagnostic models used neuroimaging features for diagnosis, ignoring patients' clinical and biological information. This makes the AD diagnosis inaccurate. In this study, we propose a novel multimodal feature transformation and fusion model for AD diagnosis. The feature transformation aims to avoid the difference in feature dimensions between different modal data and further mine the significant features for AD diagnosis. A geometric algebra-based feature extension method is proposed to obtain different levels of high-dimensional features from patients' clinical and personal biological data. Then, an influence degree-based feature filtration algorithm is proposed to filtrate those features that have no apparent guiding significance for AD diagnosis. Finally, an ANN (Artificial Neural Network)-based framework is designed to fuse transformed features with neuroimaging features extracted by CNN (Convolutional Neural Network) for AD diagnosis. The more in-depth feature mining of patients' clinical information and biological information can significantly improve the performance of computer-aided AD diagnosis. The experiments are obtained on the ADNI dataset. Our proposed model can converge faster and achieves 96.2% accuracy in AD diagnostic task and 87.4% accuracy in MCI (Mild Cognitive Impairment) diagnostic task. Compared with other methods, our proposed approach has an excellent performance in AD diagnosis and surpasses SOTA (state-of-the-art) methods. Therefore, our model can provide more reasonable suggestions for clinicians to diagnose and treat disease.
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http://dx.doi.org/10.1016/j.compbiomed.2022.105901DOI Listing
July 2022

Detecting COVID-19 patients via MLES-Net deep learning models from X-Ray images.

BMC Med Imaging 2022 07 30;22(1):135. Epub 2022 Jul 30.

School of Computer and Communication Engineering, Changsha University of Science and Technology, Changsha, 410114, China.

Background: Corona Virus Disease 2019 (COVID-19) first appeared in December 2019, and spread rapidly around the world. COVID-19 is a pneumonia caused by novel coronavirus infection in 2019. COVID-19 is highly infectious and transmissible. By 7 May 2021, the total number of cumulative number of deaths is 3,259,033. In order to diagnose the infected person in time to prevent the spread of the virus, the diagnosis method for COVID-19 is extremely important. To solve the above problems, this paper introduces a Multi-Level Enhanced Sensation module (MLES), and proposes a new convolutional neural network model, MLES-Net, based on this module.

Methods: Attention has the ability to automatically focus on the key points in various information, and Attention can realize parallelism, which can replace some recurrent neural networks to a certain extent and improve the efficiency of the model. We used the correlation between global and local features to generate the attention mask. First, the feature map was divided into multiple groups, and the initial attention mask was obtained by the dot product of each feature group and the feature after the global pooling. Then the attention masks were normalized. At the same time, there were two scaling and translating parameters in each group so that the normalize operation could be restored. Then, the final attention mask was obtained through the sigmoid function, and the feature of each location in the original feature group was scaled. Meanwhile, we use different classifiers on the network models with different network layers.

Results: The network uses three classifiers, FC module (fully connected layer), GAP module (global average pooling layer) and GAPFC module (global average pooling layer and fully connected layer), to improve recognition efficiency. GAPFC as a classifier can obtain the best comprehensive effect by comparing the number of parameters, the amount of calculation and the detection accuracy. The experimental results show that the MLES-Net56-GAPFC achieves the best overall accuracy rate (95.27%) and the best recognition rate for COVID-19 category (100%).

Conclusions: MLES-Net56-GAPFC has good classification ability for the characteristics of high similarity between categories of COVID-19 X-Ray images and low intra-category variability. Considering the factors such as accuracy rate, number of network model parameters and calculation amount, we believe that the MLES-Net56-GAPFC network model has better practicability.
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http://dx.doi.org/10.1186/s12880-022-00861-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9338656PMC
July 2022

Chitosan-based high-strength supramolecular hydrogels for 3D bioprinting.

Int J Biol Macromol 2022 Jul 27. Epub 2022 Jul 27.

Shenyang Pharmaceutical University, No. 103, Wenhua Road, Shenyang 110016, China. Electronic address:

The loss of tissues and organs is a major challenge for biomedicine, and the emerging 3D bioprinting technology has brought the dawn for the development of tissue engineering and regenerative medicine. Chitosan-based supramolecular hydrogels, as novel biomaterials, are considered as ideal materials for 3D bioprinting due to their unique dynamic reversibility and fantastic biological properties. Although chitosan-based supramolecular hydrogels have wonderful biological properties, the mechanical properties are still under early exploration. This paper aims to provide some inspirations for researchers to further explore. In this review, common 3D bioprinting techniques and the properties required for bioink for 3D bioprinting are firstly described. Then, several strategies to enhance the mechanical properties of chitosan hydrogels are introduced from the perspectives of both materials and supramolecular binding motifs. Finally, current challenges and future opportunities in this field are discussed. The combination of chitosan-based supramolecular hydrogels and 3D bioprinting will hold promise for developing novel biomedical implants.
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http://dx.doi.org/10.1016/j.ijbiomac.2022.07.206DOI Listing
July 2022

Plant community-mediated effects of grazing on plant diseases.

Oecologia 2022 Jul 30. Epub 2022 Jul 30.

State Key Laboratory of Grassland Agro-Ecosystems & College of Ecology, Lanzhou University, Lanzhou, 730000, People's Republic of China.

Grazing is one of the most important management practices for grasslands. To date, most studies on how grazing affects plant diseases have focused on a single plant species, ignoring plant community characteristics and phylogeny. We used data from a 6-year yak grazing experiment (0, 1, 2, and 3 yak(s) ha treatment) in an alpine meadow ecosystem of Qinghai-Tibetan Plateau, from which we tested grazing effects on foliar fungal diseases at both population and community levels. By measuring plant community variables (including richness, evenness, phylogenetic diversity, and composition) and disease severity, we evaluated the relative importance of plant community-mediated effects of yak grazing on community pathogen load with a multi-model inference approach. We found significant differences in pathogen load among different grazing treatments; we recorded the highest and lowest pathogen loads in the 1 yak ha treatment and in the 3 yaks ha treatment, respectively. Pielou's evenness index and community proneness (i.e., an estimate of the capacity of plant communities to support diseases) best explained variation in pathogen load, indicating that plant community-mediated effects (through evenness and proneness) of yak grazing determined pathogen load. Our study provides empirical evidence that grazing influences foliar fungal disease prevalence through plant community evenness and composition, which demonstrates the necessity of incorporating host plant community characteristics into disease load prediction frameworks.
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http://dx.doi.org/10.1007/s00442-022-05223-7DOI Listing
July 2022
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