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1.
Mult Scler Relat Disord ; 90: 105834, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39208571

ABSTRACT

OBJECTIVE: Thalamic tissue damage in multiple sclerosis (MS) follows a 'surface-in' gradient from the ventricular surface. The clinical consequences of this gradient are not completely understood. Using quantitative gradient-recalled echo (qGRE) MRI, we evaluated a periventricular thalamic gradient of tissue integrity in MS and its relationship with clinical variables. METHODS: Structural and qGRE MRI scans were acquired for a cohort of MS patients and healthy controls (HC). qGRE-derived R2t* values were used as a measure of tissue integrity. Thalamic segmentations were divided into 1-mm concentric bands radiating from the ventricular surface, excluding the CSF-adjacent band. Median R2t* values within these bands were used to calculate the periventricular thalamic gradient. RESULTS: We included 44 MS patients and 17 HC. R2t* increased slightly with distance from the ventricular surface in HC. MS patients had a steeper periventricular thalamic gradient compared to HC (mean slope 0.55 vs. 0.36; p < 0.001), which correlated with longer disease duration (ß = 0.001 /year; p = 0.027) and higher Expanded Disability Status Scale (EDSS) score (ß = 0.07 /EDSS point; p = 0.019). Left and right thalamus were symmetrically affected. CONCLUSIONS: We detected an increased thalamic gradient in MS in vivo using qGRE MRI, which correlated with disease duration and greater clinical disability. These findings further support the 'surface-in' pathology hypothesis in MS and suggest a CSF-mediated process given symmetric bi-thalamic involvement.


Subject(s)
Magnetic Resonance Imaging , Multiple Sclerosis , Thalamus , Humans , Female , Male , Adult , Thalamus/diagnostic imaging , Thalamus/pathology , Middle Aged , Multiple Sclerosis/diagnostic imaging , Multiple Sclerosis/pathology , Multiple Sclerosis/complications
2.
Sci Total Environ ; 938: 173233, 2024 Aug 15.
Article in English | MEDLINE | ID: mdl-38763196

ABSTRACT

2-Methylisoborneol (2-MIB) is a common and widely distributed off-flavor compound in water. However, the toxic mechanisms of 2-MIB on aquatic organisms remain largely unexplored. In this study, grass carp larvae were exposed to different concentrations (0, 5, and 20 µg L-1) of 2-MIB for 96 h. The accumulation of 2-MIB in the dorsal muscle was measured. Histological analysis, ultrastructure observations, and transcriptomic sequencing were conducted on the liver tissues. The results showed that 2-MIB accumulated significantly in the fish muscle, with the accumulation increasing as the exposure concentration increased through gas chromatography-mass spectrometry (GC-MS) detection. Histological and ultrastructure observations indicated that 2-MIB caused concentration-dependent inflammatory infiltration and mitochondrial damage in the liver. Transcriptomic analysis revealed lipid metabolism disorders induced by exposure to 2-MIB in grass carp. Additionally, 5 µg L-1 2-MIB affected the neurodevelopment and cardiovascular system of grass carp larvae through extracellular matrix (ECM)-receptor interaction and focal adhesion pathway. Furthermore, several pathways related to the digestive system were significantly enriched, implying that 2-MIB may impact pancreatic secretion function, protein digestion and absorption processes. These findings provide new insights into the potential toxicological mechanisms of 2-MIB.


Subject(s)
Carps , Inflammation , Transcriptome , Water Pollutants, Chemical , Animals , Water Pollutants, Chemical/toxicity , Inflammation/chemically induced , Transcriptome/drug effects , Gene Expression Profiling , Camphanes/toxicity , Liver/drug effects , Liver/pathology , Larva/drug effects
3.
ISA Trans ; 146: 366-379, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38233239

ABSTRACT

A permanent magnet linear synchronous motor (PMLSM) with discontinuous driving coils potentially applied in the underground pipeline freight delivery system is introduced in this article. Firstly, the detailed structure of the PMLSM with discontinuous driving coils is designed and presented, and the dynamic models of the PMLSM during three different processes are developed. In addition, based on the proportional-integral (PI) and the adaptive disturbance observer (DOB), a multi-loop control strategy is designed for the PMLSM with discontinuous driving coils. The critical performances of PMLSM, such as the speed precision and anti-disturbance ability, are testified in the experiment, and the results validate that the multi-loop control model with adaptive DOB used in the PMLSM with discontinuous driving coils has better speed precision than the PI+PI model by suppressing the detent force.

4.
Molecules ; 28(11)2023 Jun 01.
Article in English | MEDLINE | ID: mdl-37298966

ABSTRACT

Perfluorooctanoic acid is ubiquitous in water bodies and is detrimental to the health of organisms. Effectively removing perfluorooctanoic acid (PFOA), a persistent organic pollutant, has been a hot topic around the world. With traditional physical, chemical, and biological methods, it is difficult to effectively and completely remove PFOA, the costs are high, and it is easy to cause secondary pollution. There are difficulties in applying some technologies. Therefore, more efficient and green degradation technologies have been sought. Photochemical degradation has been shown to be a low-cost, efficient, and sustainable technique for PFOA removal from water. Photocatalytic degradation technology offers great potential and prospects for the efficient degradation of PFOA. Most studies on PFOA have been conducted under ideal laboratory conditions at concentrations that are higher than those detected in real wastewater. This paper summarizes the research status of the photo-oxidative degradation of PFOA, and it summarizes the mechanism and kinetics of PFOA degradation in different systems, as well as the influence of key factors on the photo-oxidative degradation and defluoridation process, such as system pH, photocatalyst concentration, etc. PFOA photodegradation technology's existing problems and future work directions are also presented. This review provides a useful reference for future research on PFOA pollution control technology.


Subject(s)
Fluorocarbons , Water Pollutants, Chemical , Water , Oxidation-Reduction , Fluorocarbons/chemistry , Caprylates/chemistry , Water Pollutants, Chemical/chemistry
5.
Mult Scler Relat Disord ; 73: 104659, 2023 May.
Article in English | MEDLINE | ID: mdl-37004272

ABSTRACT

BACKGROUND: Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is a distinct central nervous system (CNS) disorder that shares features with multiple sclerosis (MS) and may be misdiagnosed as MS. MOGAD and MS share a frequently relapsing clinical course and lesions with inflammatory demyelinating pathology. One key feature of MS pathology is tissue damage in normal-appearing white matter (NAWM) outside of discrete lesions, whereas the extent to which similar non-lesional damage occurs in MOGAD is not known and could be assessed using qGRE. The goal of this study was to examine the brains of people with MOGAD using quantitative gradient-recalled echo (qGRE) magnetic resonance imaging and to compare tissue damage with MS patients matched for disability. METHODS: MOGAD and MS patients were recruited to match in terms of age and disability. Similarly aged healthy control (HC) data were drawn from existing studies. qGRE brain imaging of HC (N = 15), MOGAD (N = 17), and MS (N = 15) patients was used to examine the severity and extent of tissue damage within and outside of discrete lesions. The qGRE metric R2t* is sensitive to changes in tissue microstructure and was measured in white matter lesions (WMLs), NAWM, cortical (CGM) and deep gray matter (DGM). Statistical inference was performed with linear models. RESULTS: R2t* was reduced in CGM (p = 0.00047), DGM (p = 0.0055) and NAWM (p = 0.0019) in MOGAD and MS compared to similar regions in age-matched HCs. However, the degree of R2t* reduction in all these regions was less in the MOGAD patients compared with MS. WMLs in MOGAD demonstrated reduced R2t* compared to NAWM but this reduction was modest compared to changes associated with WMLs in MS (p = 0.026). CONCLUSION: These results demonstrate abnormalities in lesional and non-lesional CNS tissues in MOGAD that are not detectable on standard MRI. The abnormalities seen in NAWM, CGM, and DGM were less severe in MOGAD compared to MS. MOGAD-related WMLs showed reduced R2t*, but were less abnormal than WMLs in MS. These data reveal damage to non-lesional tissues in two different demyelinating diseases, suggesting that damage outside of WMLs may be a common feature of demyelinating diseases. The lesser degree of R2t* abnormality in MOGAD tissues compared to MS suggests less underlying tissue damage and may underlie the greater propensity for recovery in MOGAD.


Subject(s)
Central Nervous System Diseases , Multiple Sclerosis , White Matter , Humans , Magnetic Resonance Imaging/methods , Brain/diagnostic imaging , Brain/pathology , Multiple Sclerosis/diagnostic imaging , Multiple Sclerosis/pathology , White Matter/diagnostic imaging , White Matter/pathology , Central Nervous System Diseases/pathology
6.
Sci Rep ; 13(1): 3871, 2023 Mar 08.
Article in English | MEDLINE | ID: mdl-36890239

ABSTRACT

As the current excessive accumulation of fluoride (F-) in the environment can be hazardous to human health, it is essential to remove fluoride from wastewater. In this study, diatomite (DA) was used as a raw material and modified using aluminum hydroxide (Al-DA) for use in the adsorption of F- from water bodies. SEM, EDS, XRD, FTIR, and Zeta potential characterization analyses were carried out; adsorption tests and kinetic fitting were performed, and the effects of pH, dosing quantity, and presence of interfering ions on the adsorption of F- by the materials were investigated. The results show that the Freundlich model effectively describes the adsorption process of F- on DA, which therefore involves adsorption-complexation interactions; however, the Langmuir model effectively describes the adsorption process of F- on Al-DA, corresponding to unimolecular layer adsorption mainly via ion-exchange interactions, that is, adsorption is dominated by chemisorption. Aluminum hydroxide was shown to be the main species involved in F- adsorption. The efficiency of F- removal by DA and Al-DA was over 91% and 97% for 2 h, and the adsorption kinetics were effectively fit by the quasi-secondary model, suggesting that chemical interactions between the absorbents and F- control the adsorption process. The adsorption of F- was highly dependent on the pH of the system, and the maximum adsorption performance was obtained at pH 6 and 4. The optimal dosage of DA and Al-DA was 4 g/L. Even in the presence of interfering ions, the removal of F- on Al-DA reached 89%, showing good selectivity. XRD and FTIR studies showed that the mechanism of F- adsorption on Al-DA involved ion exchange and the formation of F-Al bonds.

7.
Thorac Cancer ; 13(19): 2711-2722, 2022 10.
Article in English | MEDLINE | ID: mdl-36054506

ABSTRACT

BACKGROUND: Small cell lung cancer (SCLC) is the most malignant and common form of neuroendocrine lung cancer with pure (P-SCLC) and combined subtypes (C-SCLC). However, little is known about the differences between these two groups and in this study we aimed to provide a more comprehensive insight into SCLC. METHODS: Data from 580 postoperative patients with pathologically confirmed SCLC in Shanghai Chest Hospital from January 2010 to December 2020 were collected retrospectively. The clinical characteristics and prognosis were analyzed. RESULTS: A total of 357 P-SCLC patients and 223 C-SCLC patients were included. The results indicated that P-SCLC appeared to have a higher proportion of being located in the middle lobe than C-SCLC. The incidences of P-SCLC in patients with visceral pleural invasion (VPI) and in stage II were higher than C-SCLC, while C-SCLC was more likely to be accompanied by higher incidences of epidermal growth factor receptor (EGFR) mutation, anaplastic lymphoma kinase (ALK) rearrangement, and higher levels of CEA, SCCA and CYFRA21-1 than P-SCLC. The most common were SCLC combined with large cell neuroendocrine components among 223 C-SCLCs. Survival analysis confirmed a more favorable disease-free survival (DFS) (p = 0.016) and overall survival (OS) (p = 0.024) in patients with P-SCLCs compared with C-SCLCs. Histological type, tumor location, pN stage, adjuvant chemotherapy, serum NSE and CA125 levels were independent risk factors for survival rate in SCLC. In addition, adjuvant chemotherapy was beneficial in improving stage I P-SCLC and C-SCLC DFS and OS rates, and similar results were not seen in adjuvant radiation therapy. CONCLUSIONS: Patients with C-SCLC have a poorer prognosis than P-SCLC patients. We determined that large cell neuroendocrine carcinoma was the most common additional component of C-SCLC, and patients with this component appeared to have a longer DFS and OS than other combined components.


Subject(s)
Carcinoma, Large Cell , Carcinoma, Small Cell , Lung Neoplasms , Small Cell Lung Carcinoma , Anaplastic Lymphoma Kinase , Antigens, Neoplasm , Carcinoembryonic Antigen , Carcinoma, Large Cell/pathology , China , ErbB Receptors , Humans , Keratin-19 , Lung Neoplasms/genetics , Prognosis , Retrospective Studies
8.
Ann Clin Transl Neurol ; 9(10): 1514-1527, 2022 10.
Article in English | MEDLINE | ID: mdl-36178006

ABSTRACT

OBJECTIVE: Multiple sclerosis (MS) is a common demyelinating central nervous system disease. MRI methods that can quantify myelin loss are needed for trials of putative remyelinating agents. Quantitative magnetization transfer MRI introduced the macromolecule proton fraction (MPF), which correlates with myelin concentration. We developed an alternative approach, Simultaneous-Multi-Angular-Relaxometry-of-Tissue (SMART) MRI, to generate MPF. Our objective was to test SMART-derived MPF metric as a potential imaging biomarker of demyelination. METHODS: Twenty healthy control (HC), 11 relapsing-remitting MS (RRMS), 22 progressive MS (PMS), and one subject with a biopsied tumefactive demyelinating lesion were scanned at 3T using SMART MRI. SMART-derived MPF metric was determined in normal-appearing cortical gray matter (NAGM), normal-appearing subcortical white matter (NAWM), and demyelinating lesions. MPF metric was evaluated for correlations with physical and cognitive test scores. Comparisons were made between HC and MS and between MS subtypes. Furthermore, correlations were determined between MPF and neuropathology in the biopsied person. RESULTS: SMART-derived MPF in NAGM and NAWM were lower in MS than HC (p < 0.001). MPF in NAGM, NAWM and lesions differentiated RRMS from PMS (p < 0.01, p < 0.001, p < 0.001, respectively), whereas lesion volumes did not. MPF in NAGM, NAWM and lesions correlated with the Expanded Disability Status Scale (p < 0.01, p < 0.001, p < 0.001, respectively) and nine-hole peg test (p < 0.001, p < 0.001, p < 0.01, respectively). MPF was lower in the histopathologically confirmed inflammatory demyelinating lesion than the contralateral NAWM and increased in the biopsied lesion over time, mirroring improved clinical performance. INTERPRETATION: SMART-derived MPF metric holds potential as a quantitative imaging biomarker of demyelination and remyelination.


Subject(s)
Brain Injuries , Multiple Sclerosis, Relapsing-Remitting , Multiple Sclerosis , White Matter , Humans , Magnetic Resonance Imaging/methods , Multiple Sclerosis/diagnostic imaging , Multiple Sclerosis/pathology , Multiple Sclerosis, Relapsing-Remitting/diagnostic imaging , Multiple Sclerosis, Relapsing-Remitting/pathology , Protons , White Matter/diagnostic imaging , White Matter/pathology
9.
Front Chem ; 10: 917511, 2022.
Article in English | MEDLINE | ID: mdl-35783207

ABSTRACT

Water containing high concentrations of fluoride is widely distributed and seriously harmful, largely because long-term exposure to fluoride exceeding the recommended level will lead to fluorosis of teeth and bones. Therefore, it is imperative to develop cost-effective and environmentally friendly adsorbents to remove fluoride from polluted water sources. In this study, diatomite (DA), calcium bentonite (CB), bamboo charcoal (BC), and rice husk biochar (RHB) were tested as adsorbents to adsorb fluoride (F-) from water, and this process was characterized by scanning electron microscopy (FEI-SEM), X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FT-IR). The effects of pH, dosage, and the initial mass concentration of each treatment solution upon adsorption of F- were determined. Kinetic and thermodynamic models were applied to reveal the mechanism of defluoridation, and an orthogonal experiment was designed to obtain the optimal combination of conditions. The results show that the surfaces of CB, BC, and RHB have an irregular pore structure and rough surface, whereas DA has a rich pore structure, clear pores, large specific surface area, and high silica content. With regard to the adsorption process for F-, DA has an adsorption complex electron interaction; that of CB, BC, and RHB occur mainly via ion exchange with positive and negative charges; and CB on F- relies on chemical electron bonding adsorption. The maximum adsorption capacity of DA can reach 32.20 mg/g. When the mass concentration of fluoride is 100 mg/L, the pH value is 6.0 and the dosage is 4.0 g/L; the adsorption rate of F- by DA can reach 91.8%. Therefore, we conclude that DA soil could be used as an efficient, inexpensive, and environmentally friendly adsorbent for fluoride removal, perhaps providing an empirical basis for improving the treatment of fluorine-containing water in the future.

10.
Environ Sci Pollut Res Int ; 29(40): 60733-60743, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35426024

ABSTRACT

Recently, identifying the contamination status and assessing the health risk of per- and polyfluoroalkyl substances (PFASs) in surface water and groundwater have been of great significance. Eighteen individual PFASs were analyzed in thirty-three surface/groundwater samples during one period in a fluorine chemical park (Park A) and during two periods in Park B. The mean total concentration of 18 PFASs (∑PFASs) in Park A (9104.63 ng·L-1) was significantly higher than that in the wet season (WS) (801.68 ng·L-1) or DS (714.64 ng·L-1) in Park B. The perfluorobutane sulfonate (PFBS) was the predominant substance in the two parks, and the maximum concentration in groundwater exceeded 10,000 ng·L-1. The contamination status in the wet season (WS) was higher than that in the dry season (DS) in Park B. The ∑PFASs in Park A presented an increasing tendency following the groundwater flow direction, whereas this rule was limited to all periods in Park B. Two relative source contributions (RSCs) of 20% or 100% allowed assessing the PFASs risk to different age groups, and the results revealed that some PFASs (4 ≤ C ≤ 7 or 9 ≤ C ≤ 12) were identified as having a low risk quotient (RQ), except for perfluorooctane sulfonate (PFOS) and PFOA (C = 8). The RQmix value mainly relies on PFOA and PFOS, with a larger contribution rate of 80-90%. All assessed cases (case 1, case 2, case 3, and case 4) in all age groups revealed that infants were vulnerable to PFASs influence, followed by children, teenagers, and adults.


Subject(s)
Alkanesulfonic Acids , Fluorocarbons , Water Pollutants, Chemical , Adolescent , Alkanesulfonic Acids/analysis , Child , China , Environmental Monitoring/methods , Fluorides , Fluorine , Fluorocarbons/analysis , Humans , Risk Assessment , Water , Water Pollutants, Chemical/analysis
11.
J Cent Nerv Syst Dis ; 14: 11795735221084842, 2022.
Article in English | MEDLINE | ID: mdl-35370433

ABSTRACT

Background: Multiple sclerosis (MS) lesions typically form around a central vein that can be visualized with FLAIR* MRI, creating the central vein sign (CVS) which may reflect lesion pathophysiology. Herein we used gradient echo plural contrast imaging (GEPCI) MRI to simultaneously visualize CVS and measure tissue damage in MS lesions. We examined CVS in relation to tissue integrity in white matter (WM) lesions and among MS subtypes. Objective: We aimed to determine if CVS positive lesions were specific to MS subtype, if CVS can be detected consistently among readers using the GEPCI method, and if there were differences in tissue damage in lesions with vs without CVS. Subjects and Methods: Thirty relapsing-remitting MS (RRMS) subjects and 38 primary and secondary progressive MS (PMS) subjects were scanned with GEPCI protocol at 3T. GEPCI T2*-SWI images were generated to visualize CVS. Two investigators independently evaluated WM lesions for CVS and measured lesion volumes. To estimate tissue damage severity, total lesion volume, and mean lesion volume, R2t*-based tissue damage score (TDS) of individual lesions and tissue damage load (TDL) were measured for CVS+, CVS-, and confluent lesions. Spearman correlations were made between MRI and clinical data. One-way ANCOVA with age and sex as covariates was used to compare measurements of CVS+ vs CVS- lesions in each individual. Results: 398 of 548 lesions meeting inclusion criteria showed CVS. Most patients had ≥40% CVS+ lesions. CVS+ lesions were present in similar proportion among MS subtypes. Interobserver agreement was high for CVS detection. CVS+ and confluent lesions had higher average and total volumes vs CVS- lesions. CVS+ and confluent lesions had more tissue damage than CVS- lesions based on TDL and mean TDS. Conclusion: CVS occurred in RRMS and PMS in similar proportions. CVS+ lesions had greater tissue damage and larger size than CVS- lesions.

12.
Sci Rep ; 12(1): 3370, 2022 03 01.
Article in English | MEDLINE | ID: mdl-35232998

ABSTRACT

Contamination and adverse effects from various pollutants often appear in abandoned industrial regions. Thus, nine groundwater samples were collected from the vicinity of the fluorochemical industry in Fuxin City, Liaoning Province, to determine concentrations of the ten heavy metals arsenic (As), chromium (Cr), cadmium (Cd), lead (Pb), nickel (Ni), copper (Cu), manganese (Mn), zinc (Zn), iron (Fe) and mercury(Hg), as well as those of fluorine (F-) and eighteen poly- and perfluorinated substances (PFASs), analyse correlation relationships, and assess the health risks for different age groups. The results showed that the levels of fluorine (F-) (0.92-4.42 mg·L-1), Mn (0.0005-4.91 mg·L-1) and Fe (1.45-5.61 mg·L-1) exceeded the standard limits for drinking water. Short chain perfluorobutanoic acid (PFBA) (4.14-2501.42 ng·L-1), perfluorobutane sulfonate (PFBS) (17.07-51,818.61 ng·L-1) and perfluorohexanoic acid (PFHxA) (0.47-936.32 ng·L-1) were the predominant substances from the PFASs group. No individual PFASs levels had significant relationships with F- or heavy metal contents. There was a positive relationship between short chain PFASs concentrations and water depth and a negative relationship between long chain PFASs concentration and water depth. The hazard quotient (HQ) decreased in the order F- > heavy metals > PFASs and also decreased for older age groups. In addition, As, Fe, Mn and perfluorooctanoic acid (PFOA) were the main sources of risk from the heavy metal and PFASs groups, respectively.


Subject(s)
Drinking Water , Environmental Pollutants , Fluorocarbons , Groundwater , Mercury , Metals, Heavy , Water Pollutants, Chemical , China , Drinking Water/chemistry , Environmental Monitoring/methods , Environmental Pollutants/analysis , Fluorides/analysis , Fluorine/analysis , Fluorocarbons/analysis , Groundwater/chemistry , Mercury/analysis , Metals, Heavy/analysis , Risk Assessment , Water Pollutants, Chemical/analysis
13.
Mult Scler ; 28(10): 1515-1525, 2022 09.
Article in English | MEDLINE | ID: mdl-35196933

ABSTRACT

BACKGROUND: Imaging biomarkers of progressive multiple sclerosis (MS) are needed. Quantitative gradient recalled echo (qGRE) magnetic resonance imaging (MRI) evaluates microstructural tissue damage in MS. OBJECTIVE: To evaluate qGRE-derived R2t* as an imaging biomarker of MS progression compared with atrophy and lesion burden. METHODS: Twenty-three non-relapsing progressive MS (PMS), 22 relapsing-remitting MS (RRMS), and 18 healthy control participants underwent standard MS physical and cognitive neurological assessments and imaging with qGRE, FLAIR, and MPRAGE at 3T. PMS subjects were tested clinically and imaged every 9 months over 45 months. Imaging measures included lesion burden, atrophy, and R2t* in cortical gray matter (GM), deep GM, and normal-appearing white matter (NAWM). Longitudinal analysis of clinical performance and imaging biomarkers in PMS subjects was conducted via linear models with subject as repeated, within-subject factor. Relationship between imaging biomarkers and clinical scores was assessed by Spearman rank correlation. RESULTS: R2t* reductions correlated with neurological impairment cross-sectionally and longitudinally. PMS patients with clinically defined disease progression (N = 13) showed faster decrease of R2t* in NAWM and deep GM compared with the clinically stable PMS group (N = 10). Importantly, tissue damage measured by R2t* outperformed lesion burden and atrophy as a biomarker of progression during the study period. CONCLUSION: qGRE-derived R2t* is a potential imaging biomarker of MS progression.


Subject(s)
Multiple Sclerosis, Chronic Progressive , Multiple Sclerosis, Relapsing-Remitting , Multiple Sclerosis , Atrophy/pathology , Brain/diagnostic imaging , Brain/pathology , Gray Matter/diagnostic imaging , Gray Matter/pathology , Humans , Magnetic Resonance Imaging/methods , Multiple Sclerosis/pathology , Multiple Sclerosis, Chronic Progressive/diagnostic imaging , Multiple Sclerosis, Chronic Progressive/pathology , Multiple Sclerosis, Relapsing-Remitting/diagnostic imaging , Multiple Sclerosis, Relapsing-Remitting/pathology
14.
ISA Trans ; 126: 263-275, 2022 Jul.
Article in English | MEDLINE | ID: mdl-34446284

ABSTRACT

The rotating characteristic and the stability analysis of unsymmetrical magnetically suspended motor (MSM) are investigated in the article. Firstly, the dynamic functions of unsymmetrical MSM with different moment of inertia ratios and suspension span ratios are developed. Based on the equation of radial rotation, the open-loop pole and the frequency response are analyzed, so relationships among critical whirling frequency, moment of inertia ratio and suspension span ratio are established. Moreover, relationships among rotating characteristic, moment of inertia ratio and suspension span ratio are investigated, and then the rotation stability criterion of unsymmetrical MSM based on dual-frequency bode diagram is developed. Finally, the results prove that the proposed rotation analysis method is a potential way to analyze rotating characteristic of unsymmetrical MSM.

15.
J Adv Res ; 31: 191-205, 2021 Jul.
Article in English | MEDLINE | ID: mdl-34194842

ABSTRACT

INTRODUCTION: The inertial stabilization platform (ISP) is widely used in the earth observation system to stably track the line of sight of the payload because it could isolate vibrations and angular motions of the aviation platform. OBJECTIVES: an active magnetic actuator (AMA) system integrating the axial and the radial control is used to levitate the azimuth gimbal to improve attitude stabilization precision and dynamic performance of the ISP, and then the dynamic model of azimuth gimbal is developed. METHODS: The magnetic force and the gimbal torque of the axial-radial integrated AMA system are investigated, and the attitude information of the suspended azimuth gimbal is measured. RESULTS: The attitude stabilization precision of azimuth gimbal is confined at 0.02°, and the control bandwidth of the axial-radial integrated AMA system could exceed 100 Hz. CONCLUSION: the ISP with an axial-radial integrated AMA system has better attitude stabilization precision and wider control frequency than the pure mechanical ISP, so it is potential to be applied in the airborne remote sensing system to improve the measurement precision.

16.
Sci Rep ; 11(1): 10052, 2021 05 12.
Article in English | MEDLINE | ID: mdl-33980889

ABSTRACT

Numerous factors can influence the force exerted by clear aligners on teeth. This study aimed to investigate the stability of the force delivered by two different material appliances. 90 clear aligners with 2 materials and three different activations were designed and fabricated. Then, a device was employed to measure the force generated by the two types of PET-G material appliances immersed in artificial saliva for 0, 3, 7, 10, 14 days. Scanning electron microscopy was applied to observe the morphologic alterations on the aligner surfaces, respectively. The forces generated by different activation appliance exhibited differently, 0.0 mm < 0.1 mm < 0.2 mm. In addition, increasing the immersion times and the orthodontic force also decreased, but the forces decreased differently. Compared with the forces of conventional PETG appliances with 0.20 mm activation, the modified PETG appliances with the same activation exhibited significantly higher mean force. When comparing the mean force for modified PETG appliances after 10 and 14 days with conventional PETG appliances, the delivery forces exhibited significant differences (P < 0.05). The force delivered by both materials decreased obviously following artificial saliva immersion, and the force generated by modified aligners exhibited better stability than conventional aligners.

17.
Zhongguo Zhen Jiu ; 41(1): 59-64, 2021 Jan 12.
Article in Chinese | MEDLINE | ID: mdl-33559444

ABSTRACT

OBJECTIVE: To compare the clinical effect between electroacupuncture (EA) at Neima point and Neiguan (PC 6) and epidural nerve block for preemptive analgesia in patients undergoing thoracic surgery. METHODS: Sixty patients with elective radical esophagectomy were randomly divided into a group A, a group B and a control group, 20 cases in each group. The patients in the group A were treated with injection of 20 mL 0.375% ropivacaine at epidural space 30 min before anesthesia induction, followed by normal anesthesia during operation; the patients in the group B were treated with 30 min EA at bilateral Neima point and Neiguan (PC 6) before anesthesia induction, followed by normal anesthesia during operation; the patients in the control group were treated with general anesthesia alone. Patient-controlled intravenous analgesia was applied for all the patients. The mean arterial pressure (MAP) and heart rate (HR) were recorded at the following time points: before acupuncture/epidural puncture (T0), skin incision (T1), extubation (T2) and 2 h after operation (T3); the dosage of anesthetics and extubation time were recorded; the plasma levels of ß-endorphin (ß-EP), 5-hydroxytryptamine (5-HT) and prostaglandin E2 (PGE2) were measured at the following time points: T0, T3, 12 h after operation (T4), 24 h after operation (T5) and 48 h after operation (T6). Visual analogue scale (VAS) was used to evaluate the analgesic effect. RESULTS: The MAP at T1 and T2 in the group A was lower than that in group B and control group (P<0.05), and HR at T1 and T2 was lower than that in control group (P<0.05). The MAP and HR at T1 and T2 in the group B were lower than those in the control group (P<0.05). The dosage of remifentanil in the group A and group B was lower than that in the control group (P<0.05), and extubation time was earlier than that in the control group (P<0.05). The content of ß-EP at T4, T5 and T6 in the group B was higher than that in the group A and control group (P<0.05); the contents of 5-HT and PGE2 at T3, T4 and T5 in the group A and group B were lower than those in the control group (P<0.05). The VAS scores at T3, T4 and T5 in the group A and group were lower than those in the control group (P<0.05). CONCLUSION: The preemptive analgesia of EA at Neima point and Neiguan (PC 6) and epidural nerve block could both provide effective perioperative analgesia for thoracic surgery. The EA could better maintain intraoperative hemodynamics and has less physiological disturbance.


Subject(s)
Electroacupuncture , Nerve Block , Thoracic Surgery , Anesthesia, General , Epidural Space , Humans
18.
Neurochem Res ; 46(2): 367-378, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33201401

ABSTRACT

Impaired homeostasis of copper has been linked to different pathophysiological mechanisms in neurodegenerative diseases and oxidative injury has been proposed as the main mechanism. This study aims to use curcumin, a widely used antioxidative and anti-apoptotic agent, to exert the neuroprotective effect against copper in vitro and illuminate the underlying mechanism. The effect of curcumin was examined by using a cell counting kit-8 assay, flow cytometry, immunofluorescence, spectrophotometer, and western blot. Results revealed that after pretreatment with curcumin for 3 h, copper-induced toxicity and apoptosis show a significant decline. Further experiments showed that curcumin not only decreased the production of ROS and MDA but also increased the activities of the ROS scavenging enzymes SOD and CAT. Moreover, curcumin treatment alleviated the decrease in mitochondrial membrane potential and the nuclear translocation of cytochrome c induced by copper. The protein levels of pro-caspase 3, pro-caspase 9, and PARP1 were up-regulated and the Bax/Bcl-2 ratio was down-regulated in the presence of curcumin. Taken together, our study demonstrates that curcumin has neuroprotective properties against copper in SH-SY5Y cells and the potential mechanisms might be related to oxidative stress and mitochondrial apoptosis.


Subject(s)
Apoptosis/drug effects , Curcumin/therapeutic use , Heavy Metal Poisoning, Nervous System/drug therapy , Mitochondria/drug effects , Neuroprotective Agents/therapeutic use , Oxidative Stress/drug effects , Antioxidants/therapeutic use , Cell Line, Tumor , Copper , Cytochromes c/metabolism , Humans
19.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-877550

ABSTRACT

OBJECTIVE@#To compare the clinical effect between electroacupuncture (EA) at Neima point and Neiguan (PC 6) and epidural nerve block for preemptive analgesia in patients undergoing thoracic surgery.@*METHODS@#Sixty patients with elective radical esophagectomy were randomly divided into a group A, a group B and a control group, 20 cases in each group. The patients in the group A were treated with injection of 20 mL 0.375% ropivacaine at epidural space 30 min before anesthesia induction, followed by normal anesthesia during operation; the patients in the group B were treated with 30 min EA at bilateral Neima point and Neiguan (PC 6) before anesthesia induction, followed by normal anesthesia during operation; the patients in the control group were treated with general anesthesia alone. Patient-controlled intravenous analgesia was applied for all the patients. The mean arterial pressure (MAP) and heart rate (HR) were recorded at the following time points: before acupuncture/epidural puncture (T@*RESULTS@#The MAP at T@*CONCLUSION@#The preemptive analgesia of EA at Neima point and Neiguan (PC 6) and epidural nerve block could both provide effective perioperative analgesia for thoracic surgery. The EA could better maintain intraoperative hemodynamics and has less physiological disturbance.


Subject(s)
Humans , Anesthesia, General , Electroacupuncture , Epidural Space , Nerve Block , Thoracic Surgery
20.
Sci Prog ; 103(3): 36850420951389, 2020.
Article in English | MEDLINE | ID: mdl-32885729

ABSTRACT

For a hybrid magnetically suspended flywheel (MSFW) rotor suspended by permanent magnet biased active magnetic bearing (AMB) and passive magnetic bearing (PMB), the dynamic functions are nonlinear and coupling among different degrees of freedom (DOFs). In this article, the nonlinear dynamic functions in two controllable DOFs of the hybrid MSFW rotor are developed based on the equivalent magnetic circuit, and then the nonlinear dynamic function is linearized by using the state feedback exact linearization (SFEL) in order to minimize the coupling in two controllable DOFs. Furthermore, an optimal control based on the SFEL model is designed to reduce displacement runout and coupling among two controllable DOFs of the hybrid MSFW rotor at the rated speed. Finally, the simulation and experimental results validate the effectiveness of the optimal control based on SFEL model, and the stability of the hybrid MSFW rotor with an impulse-type disturbance is improved.

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