Publications by authors named "Siqi Zhang"

165 Publications

Effects of four different adjuvants separately combined with Aeromonas veronii inactivated vaccine on haematoimmunological state, enzymatic activity, inflammatory response and disease resistance in crucian carp.

Fish Shellfish Immunol 2021 Sep 6. Epub 2021 Sep 6.

College of Veterinary Medicine, College of Animal Science and Technology, Jilin Provincial Engineering Research Center of Animal Probiotics, Key Laboratory of Animal Production and Product Quality Safety of Ministry of Education, Jilin Agricultural University, Changchun, Jilin, 130118, China. Electronic address:

The purpose of the current study was to explore the immunomodulatory effects of different adjuvants combined with inactivated vaccines under Aeromonas veronii TH0426 infection in crucian carp. This study explored the best conditions for A. veronii as an inactivated vaccine, and included an animal safety test. Furthermore, we expressed the flagellin FlaA of the A. veronii TH0426 strain for use as an adjuvant supplemented in the diet. Crucian carp were fed 12 different experimental diets for 35 days, including the administration of 10 different adjuvants and inactivated vaccine combinations (50% aluminum hydroxide gel and inactivated vaccine combination, and inactivated vaccine with 20%, 30%, or 50% glucan, astragalus polysaccharide or flagellin), inactivated vaccine alone, and PBS control without adjuvant and inactivated vaccine. After the 42 day feeding trials, the fish were challenged with A. veronii TH0426, and the survival rate over 14 days was recorded. In addition, flagellin FlaA can be expressed normally in large amounts. All experimental groups produced higher levels of IgM serum titres than the control group in the different feeding cycles. Moreover, the activity of serum ACP, AKP, SOD, and LZM, and the expression of inflammatory factors were significantly increased in the experimental groups compared with the control group. The results of qRT-PCR analysis showed that the transcription levels of the IL-10, IL-1β, IFN-γ and TNF-α genes in heart, liver, spleen and kidney tissues were significantly enhanced by adjuvant treatment, indicating that the addition of adjuvants can significantly promote the body's inflammatory response. In addition, the phagocytic activity of leukocytes in each adjuvant treated group was significantly enhanced compared to that in the groups without adjuvant. After the A. veronii challenge, the survival rate of all adjuvant-treated groups was significantly higher than that of the control group, and the 50% flagellin adjuvant group had the highest rate of 78.37%. Overall, our findings strongly indicate that adjuvants not only significantly improve the body's immunity, but also exhibit a strong anti-infection ability. Importantly, this work provides a new perspective for the prevention and control of aquaculture diseases.
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http://dx.doi.org/10.1016/j.fsi.2021.09.003DOI Listing
September 2021

Exploring the epidemiological changes of common respiratory viruses since the COVID-19 pandemic: a hospital study in Hangzhou, China.

Arch Virol 2021 Sep 4. Epub 2021 Sep 4.

Clinical Medicine College of Hangzhou Normal University, Hangzhou, China.

Adenovirus, respiratory syncytial virus, and influenza virus are common causes of respiratory infections. The COVID-19 pandemic had a significant impact on their prevalence. The aim of this study was to analyze the epidemic changes of common respiratory viruses in the Affiliated Hospital of Hangzhou Normal University in Hangzhou, China, from October of 2017 to February of 2021. We collected statistics from 121,529 patients in the outpatient and inpatient departments of the hospital who had throat or nose swabs collected for testing for four virus antigens by the colloidal gold method. Of these, 13,200 (10.86%) were positive for influenza A virus, 8,402 (6.91%) were positive for influenza B virus, 6,056 (4.98%) were positive for adenovirus, and 4,739 (3.90%) were positive for respiratory syncytial virus. The positivity rates of the influenza A virus (0-14 years old, P = 0.376; over 14 years old, P = 0.197) and respiratory syncytial virus (0-14 years old, P = 0.763; over 14 years old, P = 0.465) did not differ significantly by gender. After January of 2020, influenza virus infection decreased significantly. The positivity rate of respiratory syncytial virus remained high, and its epidemic season was similar to before. Strict respiratory protection and regulation of crowd activities have a great impact on the epidemic characteristics of viruses. After major changes in the public health environment, virus epidemics and their mutations should be monitored closely, extensively, and continuously.
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http://dx.doi.org/10.1007/s00705-021-05214-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8417671PMC
September 2021

Emerging Applications of Boron Nitride Nanotubes in Energy Harvesting, Electronics, and Biomedicine.

ACS Omega 2021 Aug 4;6(32):20722-20728. Epub 2021 Aug 4.

Department of Physics, Michigan Technological University, 118 Fisher Hall, 1400 Townsend Drive, Houghton, Michigan 49931, United States.

Boron nitride nanotubes (BNNTs) are structurally and mechanically similar to carbon nanotubes (CNTs). In contrast, BNNTs exhibit unique properties for being electrically insulating and optically transparent due to the polarized boron nitride bonds. All these properties have prevented the use of BNNTs for energy harvesting and electronic devices for more than 25 years. During the past few years, researchers have started to demonstrate a series of novel applications of BNNTs based on unique properties not found on CNTs. For example, these novel applications include osmotic power harvesting using the charged inner surfaces of BNNTs, room-temperature single-electron transistors using insulating BNNTs as the tunneling channels, high-brightness fluorophores that can be 1000-times brighter than regular dyes, and transistors based on Tellurium atomic chains filled inside BNNTs. We have reviewed some of these emerging applications and provided our perspective for future work.
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http://dx.doi.org/10.1021/acsomega.1c02586DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8374898PMC
August 2021

Research Progress of Deep Learning in the Diagnosis and Prevention of Stroke.

Biomed Res Int 2021 9;2021:5213550. Epub 2021 Aug 9.

First Affiliated Hospital, Heilongjiang University of Chinese Medicine, No. 26 Heping Road, Harbin, China.

In order to evaluate the importance of deep learning techniques in stroke diseases, this paper systematically reviews the relevant literature. Deep learning techniques have a significant impact on the diagnosis, treatment, and prediction of stroke. In addition, this study also discusses the current bottlenecks and the future development prospects of deep learning technology.
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http://dx.doi.org/10.1155/2021/5213550DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8370809PMC
August 2021

Automatic consecutive context perceived transformer GAN for serial sectioning image blind inpainting.

Comput Biol Med 2021 Sep 10;136:104751. Epub 2021 Aug 10.

Division of Biomedical Engineering, China Medical University, Shenyang, Liaoning, People's Republic of China. Electronic address:

Background And Objective: Serial sectioning is the routine method in histology study. In order to restore the defective images in section stack, and overcome the limitations of manual annotation of broken areas, we developed a fully automatic approach for locating and restoring the defective image stack.

Methods: We proposed a novel end-to-end framework named automatic consecutive context perceived transformer GAN (ACCP-GAN) for fully automatic serial sectioning image blind inpainting. The first stage network (auto-detection module) was designed to detect the broken areas and repair them roughly, then guided the second stage network (refined inpainting module) to generate these expected patches precisely; therefore, the segmentation part was integrated into restoring part. The transformer module (SPTransformer), based on self-attention mechanism, was introduced to make the refined inpainting module focus on the features from neighboring images to help in correcting inpainting results. Moreover, gated convolution was largely used to extract features from normal parts in the defective image. The framework was trained and validated on the N7 dataset (803 images), and the generalization ability of the model was tested on the E17 (701 images) and N5 (413 images) datasets, all of these images were collected for previous kidney study.

Results: N7 dataset was divided into training, validation, and test sets with a ratio of 6:2:2. Our model performed well in broken areas segmentation with the accuracy = 0.9995. The final restoration got the best performance with FSIM = 0.9478, MS-SSIM = 0.9592, PSNR = 29.7903, VIF = 0.8543, and FID = 47.2252 compared to the popular inpainting methods. The model was further tested on E15 and N5 datasets, and the generalization ability was satisfying.

Conclusions: Our method could detect and restore the defective serial sectioning image stack automatically, even the broken patches were large on an individual image. The newly designed SPTransformer performed well in feature extraction. This method reduced the workload of manual annotation and improved the analysis or application of large scale sectioning image stack in histology research.
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http://dx.doi.org/10.1016/j.compbiomed.2021.104751DOI Listing
September 2021

Dynamic interaction mechanism of environment, microorganisms, and functions in anaerobic digestion of food waste with magnetic powder supplement.

Bioresour Technol 2021 Nov 26;340:125656. Epub 2021 Jul 26.

College of Agronomy, Northwest A&F University, Yangling, 712100 Shaanxi, China; Shaanxi Engineering Research Center of Circular Agriculture, Yangling, 712100, Shaanxi, China. Electronic address:

The reutilisation of food waste for the production of clean energy was promoted by supplementing magnet powder in anaerobic digestion (AD). This study found that adding 5% magnet powder optimally increased the amount of biogas produced by 61.9%, and the pH and volatile fatty acids (VFA) content had the greatest correlation with biogas production. A further metagenomics analysis in the early, middle, and late stages of the AD revealed that interaction between bacteria and archaea had highest explanation rate for pH and VFA changes rather than enzymes. Moreover, the 5% magnet powder increased the proportion of the CO methanogenesis and decreased the acetate methanogenesis on day 15 of peak biogas production. And it was an innovative discovery that conversion of tetrahydromethanopterin S-methyltransferase to methane increased, which is an important common node of methanogenesis metabolic and may be the fundamental reason for the increase in biogas production caused by magnetic powder.
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http://dx.doi.org/10.1016/j.biortech.2021.125656DOI Listing
November 2021

Tripeptide-based macroporous hydrogel improves the osteogenic microenvironment of stem cells.

J Mater Chem B 2021 Aug;9(30):6056-6067

School of Stomatology, Xuzhou Medical University, Xuzhou 221004, China and Department of Stomatology, The Affiliated Hospital of Xuzhou Medical University, Xuzhou 221004, China.

Due to the ability to combine multiple osteogenic induction "cues" at the same time, hydrogels are widely used in the three-dimensional (3D) culture of human mesenchymal stem cells (hMSCs) and osteoinduction. However, the survival and proliferation of stem cells in a 3D culture system are limited, which reduces their osteogenic differentiation efficiency. In addition, the cells inside the hydrogel are prone to apoptosis due to hypoxia, which is a serious challenge for tissue engineering based on stem cells. In this study, a tripeptide-based macroporous alginate hydrogel was prepared to improve the osteogenic microenvironment of stem cells. The arginine-glycine-aspartate (RGD) peptide promoted the adhesion and proliferation of stem cells, and the degradation of gelatin microspheres (GMs) produced a macroporous structure to enhance further the migration and aggregation of stem cells. Mesoporous silica nanoparticles (MSNs) sustained-release bone-forming peptide-1 (BFP-1) induced osteogenic differentiation, and the sustained release of the QK peptide from the GMs promoted angiogenesis. In vitro experiments have shown that this functionalized hydrogel stimulates the proliferation of hMSCs, encourages larger cell cluster formation, and enhances the osteogenic differentiation efficiency. The released QK facilitates the proliferation and migration of endothelial cells. In vivo experiments have also verified that this system has a better osteogenic effect, and more blood vessels were observed inside the hydrogel, than in other systems. In general, this research has led to the development of a tripeptide macroporous hydrogel that can simultaneously promote osteogenesis and angiogenesis, showing great promise for applications of 3D cultures and stem cell-based tissue engineering.
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http://dx.doi.org/10.1039/d1tb01175hDOI Listing
August 2021

Melatonin increases leaf disease resistance and saponin biosynthesis in Panax notogiseng.

J Plant Physiol 2021 Aug 26;263:153466. Epub 2021 Jun 26.

Laboratory of Sustainable Utilization of Panax notoginseng Resources, State Administration of Traditional Chinese Medicine, Key Laboratory of Panax notoginseng in Yunnan Province, Panax notoginseng Research Institute in Yunnan Province, Faculty of Life Science and Technology, Kunming University of Science and Technology, 650500, Kunming, Yunnan, China. Electronic address:

Panax notoginseng (Bruk.) FH Chen is a valuable traditional herb in China, with saponins being the main medicinal components in its roots. However, leaf diseases are a major factor limiting growth and production of P. notoginseng. Melatonin is a ubiquitous signaling molecule associated with abiotic stress resistance. In this study, we investigated the role of melatonin in leaf disease resistance of P. notoginseng in field conditions. Additionally, saponin concentrations were analyzed to evaluate the suitability of melatonin use in agricultural practice. Our results showed that exogenous application of melatonin promoted the endogenous phytomelatonin accumulation via upregulation of genes involved in its biosynthesis. The application of 10 μM melatonin decreased the incidence of leaf diseases (gray mold, round spot, and black spot) by about 40% compared with the solvent control, which might have been due to the increased expression of genes associated with immunity and disease resistance. Furthermore, concentrations of saponins and expression of their biosynthesis-related genes were significantly increased by melatonin. Taken together, the data presented here suggested that melatonin could be used in agricultural management of P. notoginseng because it increased leaf disease resistance and biosynthesis of saponins.
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http://dx.doi.org/10.1016/j.jplph.2021.153466DOI Listing
August 2021

A novel water-soluble near-infrared fluorescent probe for monitoring mitochondrial viscosity.

Talanta 2021 Oct 8;233:122592. Epub 2021 Jun 8.

College of Chemistry, Jilin Province Research Center for Engineering and Technology of Spectral Analytical Instruments, Jilin University, Qianjin Street 2699, Changchun, 130012, China. Electronic address:

Mitochondria, the main source of energy of cells, play a significant role in aerobic respiration process. Some stimulants can result in changes of mitochondrial microenvironments such as viscosity, pH and polarity. Abnormal changes of mitochondrial viscosity have been shown to relate to pathological activities and diseases. Therefore, it is critical to focus our attention on mitochondrial viscosity under different conditions. A novel organic water-soluble molecule called JLQL that could monitor viscosity was conveniently synthesized in two steps. The near-infrared sensor with maximum emission wavelength of 734.6 nm and the Stokes shift of 134.6 nm consisted of a fluorophore and a mitochondrial-targeting moiety as an acceptor group; the two were connected by a double bond. The fluorescence intensity of the sensor increased 175 times with the enhancement of viscosity of a PBS-glycerol system. The interference of other microenvironments such as pH and polarity and other interference analytes could be reduced. JLQL could sensitively and selectively differentiate different levels of mitochondrial viscosity induced by monensin or nystatin. Furthermore, the probe may provide an attractive way to monitor real-time changes of viscosity during mitophagy. Possessing the above properties, JLQL can potentially be employed as a powerful tool for the observation of mitochondrial viscosity.
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http://dx.doi.org/10.1016/j.talanta.2021.122592DOI Listing
October 2021

A neoteric dual-signal colorimetric fluorescent probe for detecting endogenous/exogenous hydrogen peroxide in cells and monitoring drug-induced hepatotoxicity.

Talanta 2021 Oct 1;233:122578. Epub 2021 Jun 1.

College of Chemistry, Jilin Province Research Center for Engineering and Technology of Spectral Analytical Instruments, Jilin University, Qianjin Street 2699, Changchun, 130012, China. Electronic address:

Hydrogen peroxide (HO), one of the most important reactive oxygen species (ROS), can be generated endogenously in the liver and has been deemed as a biomarker for evaluating drug-induced liver injury (DILI). Therefore, it is highly crucial to construct an effective method for detecting HO in the liver in order to evaluate DILI. Herein, a neoteric dual-signal colorimetric fluorescent probe XH-2 for sensing hydrogen peroxide was engineered and synthesized. Borate was grafted as a specific recognition group onto the fluorophore XH-1 (Φ = 0.34) to establish a structurally unprecedented probe. The experimental results manifested that probe XH-2 (Φ = 0.15) was able to detect hydrogen peroxide using a fluorescence method with an excellent linear range of 0-140 μM (R = 0.9974) and an especially low detection limit of 91 nM (λ = 570 nm/638 nm). In addition, the probe was capable of monitoring hydrogen peroxide in a colorimetric manner with the linear range of 0-110 μM (R = 0.9965). Furthermore, the specificity, applicability in serum (98.6-109.1%) and indirect detection of glucose make the probe XH-2 a superior probe. Based on its low cytotoxicity, the probe was successfully applied to monitor endogenous/exogenous hydrogen peroxide and quantitatively determine the concentration level of hydrogen peroxide at a range of 0-120 μM (R = 0.9859) in HepG2 cells. Ultimately, the probe could effectively monitor the level of hydrogen peroxide during DILI in HepG2 cells.
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http://dx.doi.org/10.1016/j.talanta.2021.122578DOI Listing
October 2021

Ambient air pollution and low temperature associated with case fatality of COVID-19: A nationwide retrospective cohort study in China.

Innovation (N Y) 2021 Aug 18;2(3):100139. Epub 2021 Jun 18.

State Key Laboratory of Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, WHO Collaborating Centre for Vector Surveillance and Management, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China.

The evidence for the effects of environmental factors on COVID-19 case fatality remains controversial, and it is crucial to understand the role of preventable environmental factors in driving COVID-19 fatality. We thus conducted a nationwide cohort study to estimate the effects of environmental factors (temperature, particulate matter [PM, PM], sulfur dioxide [SO], nitrogen dioxide [NO], and ozone [O]) on COVID-19 case fatality. A total of 71,808 confirmed COVID-19 cases were identified and followed up for their vital status through April 25, 2020. Exposures to ambient air pollution and temperature were estimated by linking the city- and county-level monitoring data to the residential community of each participant. For each participant, two windows were defined: the period from symptom onset to diagnosis (exposure window I) and the period from diagnosis date to date of death/recovery or end of the study period (exposure window II). Cox proportional hazards models were used to estimate the associations between these environmental factors and COVID-19 case fatality. COVID-19 case fatality increased in association with environmental factors for the two exposure windows. For example, each 10 μg/m increase in PM, PM, O, and NO in window I was associated with a hazard ratio of 1.11 (95% CI 1.09, 1.13), 1.10 (95% CI 1.08, 1.13), 1.09 (95 CI 1.03, 1.14), and 1.27 (95% CI 1.19, 1.35) for COVID-19 fatality, respectively. A significant effect was also observed for low temperature, with a hazard ratio of 1.03 (95% CI 1.01, 1.04) for COVID-19 case fatality per 1°C decrease. Subgroup analysis indicated that these effects were stronger in the elderly, as well as in those with mild symptoms and living in Wuhan or Hubei. Overall, the sensitivity analyses also yielded consistent estimates. Short-term exposure to ambient air pollution and low temperature during the illness would play a nonnegligible part in causing case fatality due to COVID-19. Reduced exposures to high concentrations of PM, PM, O, SO, and NO and low temperature would help improve the prognosis and reduce public health burden.
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http://dx.doi.org/10.1016/j.xinn.2021.100139DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8226106PMC
August 2021

The Mediating Roles of Core Self-Evaluation and Career Exploration in the Association Between Proactive Personality and Job Search Clarity.

Front Psychol 2021 4;12:609050. Epub 2021 Jun 4.

School of International Nursing, Hainan Medical University, Haikou, China.

In recent years, university students' employment has become an increasingly prominent problem worldwide. Improving the job search clarity of students is a great way to boost job-hunting success. Proactive personality may predict job search clarity through the mediating effects of core self-evaluation and career exploration. However, few studies have explored this relationship and the mediating roles of core self-evaluation and career exploration. To identify the relationship between a proactive personality and job search clarity and the mediating roles of core self-evaluation and career exploration, a cross-sectional survey was conducted. A total of 495 students majoring in nursing completed the questionnaire which consisted of the proactive personality scale, core self-evaluation scale, career exploration survey, and job search clarity scale. Correlation analyses and mediation analyses were conducted using SPSS 24.0 and AMOS 24.0 respectively. This study showed that students higher on the proactive personality scale were more likely to perform better on job search clarity. Core self-evaluation and career exploration have fully mediating effects on the relationship between a proactive personality and job search clarity. Therefore, interventions concentrated on cultivating proactive personality, improving core self-evaluation, and strengthening career exploration would be necessary for increasing job search clarity.
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http://dx.doi.org/10.3389/fpsyg.2021.609050DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8211878PMC
June 2021

π-Conjugated Macrocycle Host-Guest Coassembly with C60 on HOPG.

Langmuir 2021 Jun 10;37(24):7486-7491. Epub 2021 Jun 10.

CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology (NCNST), Beijing 100190, China.

Two kinds of π-conjugated macrocycles with aggregation-induced emission (AIE) properties were investigated by scanning tunneling microscopy (STM) to elucidate their self-assembly behaviors and interaction with C60 on a highly oriented pyrolytic graphite (HOPG) surface. Both TPEMC and TPEMCS could self-assemble into orderly cavity structures. However, C60 guest molecules could only successfully enter the cavity of TPEMC to form a stable TPEMC + C60 host-guest coassembly structure. Density functional theory (DFT) calculations were also used to interpret the assembly mechanisms. This work disclosed the assembly characteristic of these new types of conjugated macrocyclic compounds, which was helpful to develop new structural porous luminescent materials.
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http://dx.doi.org/10.1021/acs.langmuir.1c00886DOI Listing
June 2021

Progress in self-assemblies of macrocycles at the liquid/solid interface.

Nanotechnology 2021 Jun 28;32(38). Epub 2021 Jun 28.

CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology (NCNST), Beijing 100190, People's Republic of China.

Macrocyclic self-assemblies have gained great interest for diversified structures and potential applications, such as catalysis, magnetism, photovoltaic devices, organic light-emitting diodes. Macrocycles can present regular assembly systems at the liquid/solid interface due to the-conjugated structures. Furthermore, suitable guest molecules can be selected for constructing multi-component supramolecular co-assemblies. This review mainly summarizes macrocyclic self-assembly structures with different shapes in recent years. All of the studies are completed with the assistance of scanning tunneling microscope at the liquid/solid interface.
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http://dx.doi.org/10.1088/1361-6528/ac08bdDOI Listing
June 2021

Amphiphilic alginate-based fluorescent polymer nanoparticles: Fabrication and multifunctional applications.

Int J Biol Macromol 2021 Jul 8;183:2152-2161. Epub 2021 Jun 8.

Key Laboratory of Advanced Materials of Tropical Island Resources, Ministry of Education, School of Materials and Chemical Engineering, Hainan University, Hainan, Haikou 570228, China. Electronic address:

Alginate has been widely applied in various biological systems due to its great biocompatibility. Endowing it fluorescent imaging would make people to further understand its complex structure, process and mechanism. In this work, amphiphilic alginate conjugated with aggregation-induced emission (AIE) moiety fluorescent polymer was successfully fabricated through the Ugi one-pot condensation. The synthetic polymer particles were fully evaluated by various characterizations including H NMR, FTIR, fluorescent spectroscopies, and transmission electron microscopy (TEM). These amphiphilic alginate particles showed great multicolor fluorescence emission in both solid and solution states. The corresponding biological evaluation results confirmed that the fluorescent biopolymer showed excellent biocompatibility and desirable bioimaging property. Particularly, the leaf stomata were directly visualized using the amphiphilic AIE-active alginate biopolymer. Furthermore, the alginate-based polymer can also be employed as the drug carrier for hydrophobic curcumin. These results indicated that our synthetic AIE-active alginate particles might provide great potential for the further utilization of alginate in the understanding of various relative biological systems.
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http://dx.doi.org/10.1016/j.ijbiomac.2021.05.211DOI Listing
July 2021

Water-cooled microwave ablation array for bloodless rapid transection of the liver.

Int J Hyperthermia 2021 ;38(1):823-829

Department of General Surgery, Renmin Hospital of Wuhan University, Wuhan University, Wuhan, China.

Background: Microwaves (MWs) deliver relatively high temperatures into biological tissue and cover a large ablation zone. This study aims to evaluate the efficacy and effectiveness of water-cooled double-needle MW ablation arrays in assisting the hepatic transection of an pig model.

Methods: Our research program comprised computer modeling, tissue-mimicking phantom experiments, and pig liver experiments. Computer modeling was based on the finite element method (FEM) to evaluate ablation temperature distributions. In tissue-mimicking phantom and pig liver ablation experiments, the performances of the water-cooled MW ablation array and conventional clamp crushing liver resection were compared.

Results: FEM showed that the maximum lateral ablation diameter at 100 W output and a duration of 60 s was 3 cm (assessed at 50 °C isotherm). In the phantom, the maximum transverse ablation diameter of the double-needle MW ablation increased rapidly to 3 cm in 60 s at 50 W. The blood loss and blood loss per transection area in Group A were significantly lower than those in Group B (18 (7-26) ml vs. 34 (19-57) ml, and 2.4 (2-3.1) ml/cm vs. 6.9 (3.2-8.3) ml/cm, respectively) ( < 0.05). The transection speed in Group A (2.6(1.9-3.8) cm/min) was significantly faster than that in Group B (1.7(1.1-2.2) cm/min) ( < 0.05).

Conclusion: In this experimental model, the new water-cooled MW array-assisted liver resection (LR) has the potential advantage of less blood loss and rapid removal than the conventional LR.
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http://dx.doi.org/10.1080/02656736.2021.1912411DOI Listing
July 2021

Titanium carbide/zeolite imidazole framework-8/polylactic acid electrospun membrane for near-infrared regulated photothermal/photodynamic therapy of drug-resistant bacterial infections.

J Colloid Interface Sci 2021 Oct 24;599:390-403. Epub 2021 Apr 24.

State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, 2 Linggong Road, Dalian, Liaoning 116024, PR China. Electronic address:

Bacteria induced wound infection has become fatal healthcare issues needed to be resolved urgently. It is of vital importance to develop multifunctional therapeutic platforms to fight against increased bacterial antibiotic resistance. Herein, a titanium carbide (MXene)/zeolite imidazole framework-8 (ZIF-8)/polylactic acid (PLA) composite membrane (MZ-8/PLA) was fabricated through in-situ growth of ZIF-8 on MXene and the subsequent electrospinning process. It indicated MZ-8 can generate singlet oxygen and hyperthermia at photothermal (PTT) convention efficiency of 80.5% with bactericidal rate of more than 99.0%. In addition, MZ-8 showed remarkable antitumor efficiency in vitro and in vivo based on the combined photodynamic/photothermal therapy. Theoretical calculation illustrated MZ-8 could improve the laser activation process by acceleration of intermolecular charge transfer, reducing excitation energy, stabilizing excited states and increasing intersystem crossing rate. After incorporated into electrospun scaffolds, MZ-8/PLA exhibited potent PTT and photodynamic therapy (PDT) properties under 808 nm laser irradiation. The antibacterial rates of MZ-8/PLA were up to 99.9% and 99.8% against Escherichia coli and Methicillin-resistant staphylococcus aureus, respectively. In-vivo experimental results further confirmed that MZ-8/PLA can accelerate bacteria infected wound healing without observable resistance. This work opens a new avenue to design promising platforms for fighting against extremely drug resistant bacterial infection.
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http://dx.doi.org/10.1016/j.jcis.2021.04.109DOI Listing
October 2021

Yin-xing-tong-mai decoction attenuates atherosclerosis via activating PPARγ-LXRα-ABCA1/ABCG1 pathway.

Pharmacol Res 2021 Jul 28;169:105639. Epub 2021 Apr 28.

Institute of Hypertension, Jiangsu Province Hospital of Chinese Medicine, Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing, Jiangsu, China. Electronic address:

Atherosclerosis is now the major cause of mortality and morbidity worldwide. Formation of macrophage-derived foam cells is a hallmark of atherosclerosis, which is regulated by cholesterol uptake, intracellular metabolism, and efflux. PPARγ-LXRα-ABCA1/ABCG1 pathway plays an important part in regulating cholesterol efflux and this pathway could be a promising target for treating atherosclerosis. However, due to undesirable systemic effects, PPARγ agonist therapy for atherosclerosis remains challenging. Many traditional Chinese medicine has been well accepted and applied in atherosclerosis treatment. Yin-xing-tong-mai decoction (YXTMD) has been applied for treating atherosclerosis for decades. However, the mechanism remains to be explored. Here, we showed that YXTMD effectively attenuated atherosclerosis in ApoE mice. YXTMD increased cholesterol efflux of foam cell by upregulation of ABCA1 and ABCG1 in vivo and in vitro. Through bioinformatic analysis and experimental validation, we found that PPARγ was an important downstream effector of YXTMD in macrophages. Reduction of PPARγ significantly decreased LXRα, ABCA1, and ABCG1 expression in macrophages, with reduced cholesterol efflux. In conclusion, these findings confirmed that YXTMD attenuated atherosclerosis by activating the PPARγ-LXRα- ABCA1/ABCG1 pathway to enhance cholesterol efflux.
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http://dx.doi.org/10.1016/j.phrs.2021.105639DOI Listing
July 2021

A flexible fibrous membrane based on copper(II) metal-organic framework/poly(lactic acid) composites with superior antibacterial performance.

Biomater Sci 2021 May;9(10):3851-3859

State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, 2 Linggong Road, Dalian, Liaoning 116024, P. R. China. and Engineering Laboratory of Boric and Magnesic Functional Material Preparative and Applied Technology, 2 Linggong Road, Dalian, Liaoning 116024, P. R. China.

A flexible antibacterial fibrous membrane employing high antibacterial efficiency has great potential in healthcare applications. Herein, a three-dimensional copper(ii) metal-organic framework [Cu2(CA)(H2O)2, Cu-MOF-1] and poly(lactic acid) (PLA) composite fibrous membrane was prepared through a facile electrospinning method. The sphere-like Cu-MOF-1 was rapidly synthesized by a microwave-assisted hydrothermal reaction of Cu(ii) salts with citric acid (H4CA) in the presence of polyvinyl pyrrolidone (PVP). The surface morphology, thermal stability, mechanical properties and hydrophilicity test of the as-prepared Cu-MOF-1/PLA fibrous membrane were studied systematically. Compared with commercial copper nanoparticles (Cu-NPs), citric acid and copper citrate, Cu-MOF-1 showed higher antibacterial properties with the bacteriostatic rates of 97.9% and 99.3% against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), respectively, when the used dose was 250 μg mL-1. The Cu-MOF-1/PLA fibrous membrane also exhibited outstanding bactericidal activities against E. coli and S. aureus with the antibacterial rates up to 99.3% and 99.8%, respectively. Mechanism investigation indicated that the slowly released Cu2+ ions could destroy the microenvironment of bacteria cells and destroy the integrity and permeability of the cell membrane, leading to enzyme inactivation. Therefore, the as-prepared flexible fibrous membrane will advance progress toward developing a broad spectrum antibacterial textile for healthcare protection related applications.
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http://dx.doi.org/10.1039/d1bm00164gDOI Listing
May 2021

Toxicity of organotin compounds and the ecological risk of organic tin with co-existing contaminants in aquatic organisms.

Comp Biochem Physiol C Toxicol Pharmacol 2021 Aug 19;246:109054. Epub 2021 Apr 19.

Marine College, Shandong University, Weihai, Shandong 264209, China. Electronic address:

Although organotin (OT) use is restricted worldwide, with the development of industry and agriculture, a large amount of OT is still discharged into aquatic environments. These OTs may interact with other pollutants that cause adverse biological effects (through bioaccumulation and/or toxicity), resulting in combined toxicity. Most research on OTs have focused on the exposure of a single analyte. Information on the toxicity of OTs and coexisting pollutants is quite limited, but is developing rapidly. This is the first review paper evaluating the current state of knowledge on the combined effects of OTs with co-pollutants. This paper reviews 1) the degradation of organotin; and 2) the combined toxicity of OTs and emerging pollutants (EP), heavy metals, and organic pollutants. Future research needs are discussed to better understand the risks associated with co-exposure to OT pollutants.
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http://dx.doi.org/10.1016/j.cbpc.2021.109054DOI Listing
August 2021

A nanofluidic device for ultrasensitive and label-free detection of tetracycline in association with γ-cyclodextrin and GO.

Anal Methods 2021 04;13(15):1832-1838

School of Pharmaceutical and Materials Engineering, Taizhou University, Jiaojiang, 318000, China.

Herein, an ultrasensitive and selective nanofluidic device for tetracycline (TC) was developed in association with γ-cyclodextrin and graphene oxide (GO). The assay was designed based on the change of the nanochannel surface charge due to the selective recognition ability of GO between aptamers and TC-aptamer complexes. And γ-cyclodextrin was utilized to eliminate the excess TC since the amine group molecules were inclined to be adsorbed onto the nanochannel surface and affected the adsorption efficiency of the nanochannel. In the presence of TC, TC specifically binded to the aptamer to form TC-aptamer and was separated from GO. The TC-aptamer complexes could be quantitated with conical nanochannels coated with polyethyleneimine (PEI)/Zr4+. The redundant TC was removed by γ-cyclodextrin. The detection limit of the nanofluidic device was as low as 2 ng L-1 (S/N = 3) and the linear range was 10 ng L-1 to 10 μg L-1. Moreover, the nanofluidic device provided high specificity and good recovery rates of 94.8-109.3% in natural river, tapwater and wastewater samples. The results revealed that our study provided a new rapid detection method for trace contaminant analysis.
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http://dx.doi.org/10.1039/d0ay01868fDOI Listing
April 2021

SPARC-related modular calcium binding 1 regulates aortic valve calcification by disrupting BMPR-II/p-p38 signalling.

Cardiovasc Res 2021 Mar 23. Epub 2021 Mar 23.

Department of Cardiology.

Aims: Aortic valve calcification is more prevalent in chronic kidney disease accompanied by hypercalcemia. SPARC (Secreted Protein Acidic and Rich in Cysteine)-related modular calcium binding 1 (SMOC1) is a regulator of BMP2 signalling, but the role of SMOC1 in aortic valve calcification under different conditions has not been studied. This study aimed to investigate the roles of SMOC1 in aortic valve calcification under normal and high calcium conditions, focusing on the effects on aortic valve interstitial cells (AVICs).

Methods And Results: SMOC1 was expressed by aortic valve endothelial cells and secreted into the extracellular matrix in non-calcific valves and downregulated in calcific aortic valves. In vitro studies demonstrated that HUVEC secreted SMOC1 could enter the cytoplasm of AVICs. Overexpression of SMOC1 attenuated warfarin-induced AVIC calcification but promoted high calcium/phosphate or vitamin D-induced AVIC and aortic valve calcification by regulating BMP2 signalling both in vitro and in vivo. Co-immunoprecipitation revealed that SMOC1 binds to BMP receptor II (BMPR-II) and inhibits BMP2-induced phosphorylation of p38 (p-p38) via amino acids 372-383 of its EF-hand calcium-binding domain. Inhibition of p-p38 by the p38 inhibitor SB203580 blocked the effects of SMOC1 on BMP2 signalling and AVIC calcification induced by high calcium/phosphate medium. In high-calcium-treated AVICs, SMOC1 lost its ability to bind to BMPR-II, but not to caveolin-1, promoting p-p38 and cell apoptosis due to increased expression of BMPR-II and enhanced endocytosis.

Conclusions: These observations support that SMOC1 works as a dual-directional modulator of AVIC calcification by regulating p38-dependent BMP2 signalling transduction according to different extracellular calcium concentrations.
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http://dx.doi.org/10.1093/cvr/cvab107DOI Listing
March 2021

The mechanism of hydrating and solidifying green mine fill materials using circulating fluidized bed fly ash-slag-based agent.

J Hazard Mater 2021 08 12;415:125625. Epub 2021 Mar 12.

School of Civil and Resource Engineering, University of Science and Technology Beijing, Beijing 100083, China; Key Laboratory of High-efficient Mining and Safety of Metal Mines, Ministry of Education, Beijing 100083, China.

This study focused on classifying and disposing Circulating fluidized bed (CFB) fly ashes from the level of its origin, and proposed an optimal formulation system for clinker-free cemented backfill materials. CFB fly ash-blast furnace slag (BFS)-based cemented backfill materials with unequal strength grades are used in different locations of the goaf that require more than 1 Mpa and 4 Mpa, respectively, and the leaching levels of all toxic components are lower than the underground III water quality standard limit when the additional amount of CFB fly ash does not exceed 60 wt.%. The stable S/S of Cl is due to the combined effect of chemical fixation of HCC and physical adsorption of the C-S-H/C-A-S-H phase. B2(20 wt.% CFB fly ash) exhibits more functional hydration products and higher degree of polymerization with the hydration age extension. Ettringite is the major effective product of CFB fly ash-BFS-based cemented system due to low level of chlorine environment and HCC transformation. CFB fly ash with appropriate active AlO can dissolve and promote [AlO] to substitute [SiO] to form the C-A-S-H phase with longer chains and higher degree of polymerization with increase in Al/Si ratio of C-A-S-H/C-S-H phase.
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http://dx.doi.org/10.1016/j.jhazmat.2021.125625DOI Listing
August 2021

Cycle-Consistent Generative Adversarial Network: Effect on Radiation Dose Reduction and Image Quality Improvement in Ultralow-Dose CT for Evaluation of Pulmonary Tuberculosis.

Korean J Radiol 2021 06 9;22(6):983-993. Epub 2021 Mar 9.

The D-Lab, Department of Precision Medicine, GROW-School for Oncology and Developmental Biology, Maastricht University, Maastricht, The Netherlands.

Objective: To investigate the image quality of ultralow-dose CT (ULDCT) of the chest reconstructed using a cycle-consistent generative adversarial network (CycleGAN)-based deep learning method in the evaluation of pulmonary tuberculosis.

Materials And Methods: Between June 2019 and November 2019, 103 patients (mean age, 40.8 ± 13.6 years; 61 men and 42 women) with pulmonary tuberculosis were prospectively enrolled to undergo standard-dose CT (120 kVp with automated exposure control), followed immediately by ULDCT (80 kVp and 10 mAs). The images of the two successive scans were used to train the CycleGAN framework for image-to-image translation. The denoising efficacy of the CycleGAN algorithm was compared with that of hybrid and model-based iterative reconstruction. Repeated-measures analysis of variance and Wilcoxon signed-rank test were performed to compare the objective measurements and the subjective image quality scores, respectively.

Results: With the optimized CycleGAN denoising model, using the ULDCT images as input, the peak signal-to-noise ratio and structural similarity index improved by 2.0 dB and 0.21, respectively. The CycleGAN-generated denoised ULDCT images typically provided satisfactory image quality for optimal visibility of anatomic structures and pathological findings, with a lower level of image noise (mean ± standard deviation [SD], 19.5 ± 3.0 Hounsfield unit [HU]) than that of the hybrid (66.3 ± 10.5 HU, < 0.001) and a similar noise level to model-based iterative reconstruction (19.6 ± 2.6 HU, > 0.908). The CycleGAN-generated images showed the highest contrast-to-noise ratios for the pulmonary lesions, followed by the model-based and hybrid iterative reconstruction. The mean effective radiation dose of ULDCT was 0.12 mSv with a mean 93.9% reduction compared to standard-dose CT.

Conclusion: The optimized CycleGAN technique may allow the synthesis of diagnostically acceptable images from ULDCT of the chest for the evaluation of pulmonary tuberculosis.
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http://dx.doi.org/10.3348/kjr.2020.0988DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8154783PMC
June 2021

Chromosome inheritance and meiotic stability in allopolyploid Brassica napus.

G3 (Bethesda) 2021 02;11(2)

Division of Biological Sciences, University of Missouri, Columbia, MO 65211, USA.

Homoeologous recombination, aneuploidy, and other genetic changes are common in resynthesized allopolyploid Brassica napus. In contrast, the chromosomes of cultivars have long been considered to be meiotically stable. To gain a better understanding of the underlying mechanisms leading to stabilization in the allopolyploid, the behavior of chromosomes during meiosis can be compared by unambiguous chromosome identification between resynthesized and natural B. napus. Compared with natural B. napus, resynthesized lines show high rates of nonhomologous centromere association, homoeologous recombination leading to translocation, homoeologous chromosome replacement, and association and breakage of 45S rDNA loci. In both natural and resynthesized B. napus, we observed low rates of univalents, A-C bivalents, and early sister chromatid separations. Reciprocal homoeologous chromosome exchanges and double reductions were photographed for the first time in meiotic telophase I. Meiotic errors were non-uniformly distributed across the genome in resynthesized B. napus, and in particular homoeologs sharing synteny along their entire length exhibited multivalents at diakinesis and polysomic inheritance at telophase I. Natural B. napus appeared to resolve meiotic errors mainly by suppressing homoeologous pairing, resolving nonhomologous centromere associations and 45S rDNA associations before diakinesis, and reducing homoeologous cross-overs.
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http://dx.doi.org/10.1093/g3journal/jkaa011DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8022990PMC
February 2021

Dynamic analysis on simultaneous iEEG-MEG data via hidden Markov model.

Neuroimage 2021 06 1;233:117923. Epub 2021 Mar 1.

Wellcome Centre for Human Neuroimaging, UCL Institute of Neurology, 12 Queen Square, London WC1N 3BG, UK. Electronic address:

Background: Intracranial electroencephalography (iEEG) recordings are used for clinical evaluation prior to surgical resection of the focus of epileptic seizures and also provide a window into normal brain function. A major difficulty with interpreting iEEG results at the group level is inconsistent placement of electrodes between subjects making it difficult to select contacts that correspond to the same functional areas. Recent work using time delay embedded hidden Markov model (HMM) applied to magnetoencephalography (MEG) resting data revealed a distinct set of brain states with each state engaging a specific set of cortical regions. Here we use a rare group dataset with simultaneously acquired resting iEEG and MEG to test whether there is correspondence between HMM states and iEEG power changes that would allow classifying iEEG contacts into functional clusters.

Methods: Simultaneous MEG-iEEG recordings were performed at rest on 11 patients with epilepsy whose intracranial electrodes were implanted for pre-surgical evaluation. Pre-processed MEG sensor data was projected to source space. Time delay embedded HMM was then applied to MEG time series. At the same time, iEEG time series were analyzed with time-frequency decomposition to obtain spectral power changes with time. To relate MEG and iEEG results, correlations were computed between HMM probability time courses of state activation and iEEG power time course from the mid contact pair for each electrode in equally spaced frequency bins and presented as correlation spectra for the respective states and iEEG channels. Association of iEEG electrodes with HMM states based on significant correlations was compared to that based on the distance to peaks in subject-specific state topographies.

Results: Five HMM states were inferred from MEG. Two of them corresponded to the left and the right temporal activations and had a spectral signature primarily in the theta/alpha frequency band. All the electrodes had significant correlations with at least one of the states (p < 0.05 uncorrected) and for 27/50 electrodes these survived within-subject FDR correction (q < 0.05). These correlations peaked in the theta/alpha band. There was a highly significant dependence between the association of states and electrodes based on functional correlations and that based on spatial proximity (p = 5.6eχ test for independence). Despite the potentially atypical functional anatomy and physiological abnormalities related to epilepsy, HMM model estimated from the patient group was very similar to that estimated from healthy subjects.

Conclusion: Epilepsy does not preclude HMM analysis of interictal data. The resulting group functional states are highly similar to those reported for healthy controls. Power changes recorded with iEEG correlate with HMM state time courses in the alpha-theta band and the presence of this correlation can be related to the spatial location of electrode contacts close to the individual peaks of the corresponding state topographies. Thus, the hypothesized relation between iEEG contacts and HMM states exists and HMM could be further explored as a method for identifying comparable iEEG channels across subjects for the purposes of group analysis.
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http://dx.doi.org/10.1016/j.neuroimage.2021.117923DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8204269PMC
June 2021

Dynamic analysis on simultaneous iEEG-MEG data via hidden Markov model.

Neuroimage 2021 06 1;233:117923. Epub 2021 Mar 1.

Wellcome Centre for Human Neuroimaging, UCL Institute of Neurology, 12 Queen Square, London WC1N 3BG, UK. Electronic address:

Background: Intracranial electroencephalography (iEEG) recordings are used for clinical evaluation prior to surgical resection of the focus of epileptic seizures and also provide a window into normal brain function. A major difficulty with interpreting iEEG results at the group level is inconsistent placement of electrodes between subjects making it difficult to select contacts that correspond to the same functional areas. Recent work using time delay embedded hidden Markov model (HMM) applied to magnetoencephalography (MEG) resting data revealed a distinct set of brain states with each state engaging a specific set of cortical regions. Here we use a rare group dataset with simultaneously acquired resting iEEG and MEG to test whether there is correspondence between HMM states and iEEG power changes that would allow classifying iEEG contacts into functional clusters.

Methods: Simultaneous MEG-iEEG recordings were performed at rest on 11 patients with epilepsy whose intracranial electrodes were implanted for pre-surgical evaluation. Pre-processed MEG sensor data was projected to source space. Time delay embedded HMM was then applied to MEG time series. At the same time, iEEG time series were analyzed with time-frequency decomposition to obtain spectral power changes with time. To relate MEG and iEEG results, correlations were computed between HMM probability time courses of state activation and iEEG power time course from the mid contact pair for each electrode in equally spaced frequency bins and presented as correlation spectra for the respective states and iEEG channels. Association of iEEG electrodes with HMM states based on significant correlations was compared to that based on the distance to peaks in subject-specific state topographies.

Results: Five HMM states were inferred from MEG. Two of them corresponded to the left and the right temporal activations and had a spectral signature primarily in the theta/alpha frequency band. All the electrodes had significant correlations with at least one of the states (p < 0.05 uncorrected) and for 27/50 electrodes these survived within-subject FDR correction (q < 0.05). These correlations peaked in the theta/alpha band. There was a highly significant dependence between the association of states and electrodes based on functional correlations and that based on spatial proximity (p = 5.6eχ test for independence). Despite the potentially atypical functional anatomy and physiological abnormalities related to epilepsy, HMM model estimated from the patient group was very similar to that estimated from healthy subjects.

Conclusion: Epilepsy does not preclude HMM analysis of interictal data. The resulting group functional states are highly similar to those reported for healthy controls. Power changes recorded with iEEG correlate with HMM state time courses in the alpha-theta band and the presence of this correlation can be related to the spatial location of electrode contacts close to the individual peaks of the corresponding state topographies. Thus, the hypothesized relation between iEEG contacts and HMM states exists and HMM could be further explored as a method for identifying comparable iEEG channels across subjects for the purposes of group analysis.
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http://dx.doi.org/10.1016/j.neuroimage.2021.117923DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8204269PMC
June 2021

Dynamic analysis on simultaneous iEEG-MEG data via hidden Markov model.

Neuroimage 2021 06 1;233:117923. Epub 2021 Mar 1.

Wellcome Centre for Human Neuroimaging, UCL Institute of Neurology, 12 Queen Square, London WC1N 3BG, UK. Electronic address:

Background: Intracranial electroencephalography (iEEG) recordings are used for clinical evaluation prior to surgical resection of the focus of epileptic seizures and also provide a window into normal brain function. A major difficulty with interpreting iEEG results at the group level is inconsistent placement of electrodes between subjects making it difficult to select contacts that correspond to the same functional areas. Recent work using time delay embedded hidden Markov model (HMM) applied to magnetoencephalography (MEG) resting data revealed a distinct set of brain states with each state engaging a specific set of cortical regions. Here we use a rare group dataset with simultaneously acquired resting iEEG and MEG to test whether there is correspondence between HMM states and iEEG power changes that would allow classifying iEEG contacts into functional clusters.

Methods: Simultaneous MEG-iEEG recordings were performed at rest on 11 patients with epilepsy whose intracranial electrodes were implanted for pre-surgical evaluation. Pre-processed MEG sensor data was projected to source space. Time delay embedded HMM was then applied to MEG time series. At the same time, iEEG time series were analyzed with time-frequency decomposition to obtain spectral power changes with time. To relate MEG and iEEG results, correlations were computed between HMM probability time courses of state activation and iEEG power time course from the mid contact pair for each electrode in equally spaced frequency bins and presented as correlation spectra for the respective states and iEEG channels. Association of iEEG electrodes with HMM states based on significant correlations was compared to that based on the distance to peaks in subject-specific state topographies.

Results: Five HMM states were inferred from MEG. Two of them corresponded to the left and the right temporal activations and had a spectral signature primarily in the theta/alpha frequency band. All the electrodes had significant correlations with at least one of the states (p < 0.05 uncorrected) and for 27/50 electrodes these survived within-subject FDR correction (q < 0.05). These correlations peaked in the theta/alpha band. There was a highly significant dependence between the association of states and electrodes based on functional correlations and that based on spatial proximity (p = 5.6eχ test for independence). Despite the potentially atypical functional anatomy and physiological abnormalities related to epilepsy, HMM model estimated from the patient group was very similar to that estimated from healthy subjects.

Conclusion: Epilepsy does not preclude HMM analysis of interictal data. The resulting group functional states are highly similar to those reported for healthy controls. Power changes recorded with iEEG correlate with HMM state time courses in the alpha-theta band and the presence of this correlation can be related to the spatial location of electrode contacts close to the individual peaks of the corresponding state topographies. Thus, the hypothesized relation between iEEG contacts and HMM states exists and HMM could be further explored as a method for identifying comparable iEEG channels across subjects for the purposes of group analysis.
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http://dx.doi.org/10.1016/j.neuroimage.2021.117923DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8204269PMC
June 2021

The delivery of smoking cessation interventions by nurses who smoke: A meta-ethnographic synthesis.

J Adv Nurs 2021 Jul 24;77(7):2957-2970. Epub 2021 Feb 24.

Adult Nursing, Florence Nightingale Faculty of Nursing, King's College London, London, UK.

Aims: To gain new insights into the experiences of nurses who smoke and to understand the impact of those experiences on their delivery of smoking cessation interventions.

Design: A meta-ethnographic synthesis.

Data Sources: CINAHL, Embase, MEDLINE, PsychINFO, Web of Science and grey literature databases were searched from their inception to April 2019.

Review Methods: Meta-ethnography was employed to synthesize findings from included studies. The CASP qualitative checklist was used to appraise the quality of each study, and the GRADE-CERQual approach to appraise review findings. The synthesis is reported in accordance with the eMERGe reporting guidance.

Results: From an initial search outcome of 6,019 citations, 13 studies were included detailing the experiences of 195 nurses who were smokers or ex-smokers. Four main themes were identified beliefs, dissonance, coping mechanisms and workplace policies. An integrated conceptual map was proposed on the basis of findings. Nurses who smoke were aware of tobacco harms and their role in addressing tobacco use, which resulted in experiences of guilt and stigma. Workplace policies played a crucial role in the creation of cognitive dissonance. Nurses used different strategies to cope with dissonance such as rationalizing smoking benefits, hiding their smoking behaviour, denial of smoking risks, and failing to engage with smoking cessation interventions. Some nurses expressed more positive aspirations to cope with their dissonance, including a willingness to quit and to embrace smoking cessation interventions with their patients.

Conclusion: Implementing smoke-free policies and supportive interventions targeting nurses' cognitive dissonance may assist them to quit smoking and improve their engagement in smoking cessation practices.
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http://dx.doi.org/10.1111/jan.14783DOI Listing
July 2021

Association between short-term exposure to ambient fine particulate matter and myocardial injury in the CATHGEN cohort.

Environ Pollut 2021 Apr 5;275:116663. Epub 2021 Feb 5.

Institute of Epidemiology, Helmholtz Zentrum München, Neuherberg, Germany.

Exposure to fine particulate matter (PM) has been associated with a higher risk for coronary events. Elevated circulating cardiac troponins (cTn) are suggestive of myocardial injury in both ischemic and non-ischemic conditions. However, little is known about the association between PM and cTn. In this study, we investigated short-term PM effects on cardiac troponin T (cTnT), as well as N-terminal-pro brain natriuretic peptide (NT-pro BNP) and inflammatory biomarkers among cardiac catheterized participants. We analyzed 7444 plasma cTnT measurements in 2732 participants who presented to Duke University Hospital with myocardial infarction symptoms between 2001 and 2012, partly along with measurements of NT-pro BNP and inflammatory biomarkers. Daily PM concentrations were predicted by a neural network-based hybrid model and were assigned to participants' residential addresses. We applied generalized estimating equations to assess associations of PM with biomarker levels and the risk of a positive cTnT test (cTnT > 0.1 ng/mL). The median plasma cTnT concentration at presentation was 0.05 ng/mL and the prevalence of a positive cTnT test was 35.4%. For an interquartile range (7.6 μg/m) increase in PM on the previous day, cTnT concentrations increased by 7.7% (95% CI: 3.4-12.3) and the odds ratio of a positive cTnT test was 1.08 (1.01-1.16). Participants under 60 years (effect estimate: 15.2%; 95% CI: 7.4-23.5) or living in rural areas (12.3%; 95% CI: 4.8-20.3) were more susceptible. There was evidence for increases in fibrinogen and NT-pro BNP associated with elevated PM on the concurrent and previous two days. Our study suggests that acute PM exposure may elevate indicators of myocardial tissue damage. This finding substantiates the association of air pollution exposure with adverse cardiovascular events.
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http://dx.doi.org/10.1016/j.envpol.2021.116663DOI Listing
April 2021
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