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1.
Sensors (Basel) ; 24(5)2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38474929

RESUMO

An exhaust gas recirculation (EGR) valve is used to quickly and dynamically adjust the amount of recirculated exhaust gas, which is critical for improving engine fuel economy and reducing emissions. To address problems relating to the precise positioning of an electromotive (EM) valve under slowly varying plant dynamics and uncertain disturbances, we propose a servo control system design based on linear active disturbance rejection control (LADRC) for the EGR EM valve driven by a limited angle torque motor (LATM). By analyzing the structure of the LATM and the transmission, the dynamic model of the system is derived. In addition, to solve the problems caused by slowly varying plant dynamics and uncertain disturbances, we combine the effects of uncertain model parameters and external disturbances as the total disturbance, which is estimated in real time by an extended state observer (ESO) and then compensated. In addition, accurate angular information is obtained using a non-contact magnetic angle measurement method, and a high-speed digital communication channel is established to help implement a closed-loop position control system with improved responsiveness and accuracy. Simulation and experimental results show that the proposed servo system design can effectively ensure the precision and real-time performance of the EM valve under slowly changing plant dynamics and uncertain disturbances. The proposed servo system design achieves a full-stroke valve control accuracy of better than 0.05 mm and a full-stroke response time of less than 100 ms. The controlled valve also has good robustness under shock-type external disturbances and excellent airflow control capability. The repeatability of the airflow control is generally within 5%, and the standard deviation is less than 0.2 m3/h.

2.
Environ Geochem Health ; 46(5): 174, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38592609

RESUMO

The effects of long-term exposure to fine particulate matter (PM2.5) constituents on chronic kidney disease (CKD) are not fully known. This study sought to examine the association between long-term exposure to major PM2.5 constituents and CKD and look for potential constituents contributing substantially to CKD. This study included 81,137 adults from the 2018 to 2019 baseline survey of China Multi-Ethnic Cohort. CKD was defined by the estimated glomerular filtration rate. Exposure concentration data of 7 major PM2.5 constituents were assessed by satellite remote sensing. Logistic regression models were used to estimate the effect of each PM2.5 constituent exposure on CKD. The weighted quantile sum regression was used to estimate the effect of mixed exposure to all constituents. PM2.5 constituents had positive correlations with CKD (per standard deviation increase), with ORs (95% CIs) of 1.20 (1.02-1.41) for black carbon, 1.27 (1.07-1.51) for ammonium, 1.29 (1.08-1.55) for nitrate, 1.20 (1.01-1.43) for organic matter, 1.25 (1.06-1.46) for sulfate, 1.30 (1.11-1.54) for soil particles, and 1.63 (1.39-1.91) for sea salt. Mixed exposure to all constituents was positively associated with CKD (1.68, 1.32-2.11). Sea salt was the constituent with the largest weight (0.36), which suggested its importance in the PM2.5-CKD association, followed by nitrate (0.32), organic matter (0.18), soil particles (0.10), ammonium (0.03), BC (0.01). Sulfate had the least weight (< 0.01). Long-term exposure to PM2.5 sea salt and nitrate may contribute more than other constituents in increasing CKD risk, providing new evidence and insights for PM2.5-CKD mechanism research and air pollution control strategy.


Assuntos
Compostos de Amônio , Insuficiência Renal Crônica , Humanos , Adulto , Nitratos , China/epidemiologia , Material Particulado/toxicidade , Insuficiência Renal Crônica/induzido quimicamente , Insuficiência Renal Crônica/epidemiologia , Solo , Sulfatos , Óxidos de Enxofre
3.
Hum Reprod ; 38(8): 1560-1570, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37366630

RESUMO

STUDY QUESTION: Is there a relationship between pregnancy termination history and metabolic syndrome (MetS), and if so, is the relationship moderated by physical activity (PA)? SUMMARY ANSWER: Induced abortion, and both miscarriage and induced abortion, increased the risk of MetS, while leisure PA attenuated the effects of induced abortion, and both miscarriage and induced abortion, on the risk of MetS. WHAT IS KNOWN ALREADY: Pregnancy termination history is a risk factor for cardiovascular disease, but studies on women's history of pregnancy termination and MetS are limited. PA is a preventive behavior for MetS, but its modification effect on any association between pregnancy termination history and MetS is unknown. STUDY DESIGN, SIZE, DURATION: The cross-sectional study included 53 702 women (age range of 30-79 years old) from southwestern China who participated in the China Multi-Ethnic Cohort (CMEC) study from May 2018 to September 2019. PARTICIPANTS/MATERIALS, SETTING, METHODS: Participants self-reported both the number and type of pregnancy termination. PA was assessed primarily by asking participants about the cumulative time they spent doing PA either as their occupation, transportation, housework, and leisure activity in the past year. MetS was defined according to the National Cholesterol Education Program Adult Treatment Panel III (ATP III) criteria. MAIN RESULTS AND THE ROLE OF CHANCE: After adjusting for all confounders, the risk of MetS was significantly increased in women who experienced induced abortion alone, and both miscarriage and induced abortion, with odds ratios (ORs) of 1.08 (95% CI = 1.03-1.13) and 1.20 (95% CI = 1.08-1.33), respectively. A dose-response relationship was observed between the number of induced abortions and MetS, with the risk increasing by 3.0% for every additional induced abortion (OR = 1.03, 95% CI = 1.01-1.05). Leisure PA had a significant modification effect on the relationship between pregnancy termination history and MetS, as leisure PA attenuates the negative effects of induced abortion on MetS. LIMITATIONS, REASONS FOR CAUTION: Causality cannot be established in this study. Information on pregnancy termination and PA was collected by self-report, which might be subject to recall bias. WIDER IMPLICATIONS OF THE FINDINGS: A history of induced abortion was associated with an increased risk of MetS, and the risk increased with the number of induced abortions. Leisure PA attenuated the negative effect of induced abortion on MetS, whereas occupational and transportation PA amplified the negative effect of induced abortion on glucose. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the National Key R&D Program of China (grant no.: 2017YFC0907300) and the National Nature Science Foundation of China (grant no.: 82273745). The authors declare no conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Aborto Induzido , Aborto Espontâneo , Síndrome Metabólica , Gravidez , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Idoso , Aborto Espontâneo/epidemiologia , Aborto Espontâneo/etiologia , Síndrome Metabólica/epidemiologia , Síndrome Metabólica/etiologia , Estudos Transversais , População do Leste Asiático , Aborto Induzido/efeitos adversos , Exercício Físico
4.
Prev Med ; 177: 107776, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37951543

RESUMO

BACKGROUND: The relationship between age at menarche and metabolic dysfunction-associated fatty liver disease remains largely not clear. The objective of this study was to examine the association between age at menarche (AAM) and metabolic dysfunction-associated fatty liver disease (MAFLD) in Chinese women and whether any observed associations were mediated by early adulthood adiposity. METHODS: The cross-sectional study included 46,873 Chinese women, aged 30-79 from baseline data of the China Multi-Ethnic Cohort study. Logistic regression models were used to evaluate the association between AAM and MAFLD. Mediation analysis was adopted to examine whether early adulthood adiposity (around 25 years) mediated the association between AAM and MAFLD. RESULTS: AAM was linearly and inversely associated with the risk of MAFLD (P for nonlinearity =0.743). In a multivariable-adjusted model, the odds ratios and 95% confidence interval (ORs (95% CI)) for MAFLD comparing menarche at <12, 12, 13, 15, 16, 17, ≥18 years to menarche at 14 years were 1.290 (1.082-1.537), 1.172 (1.068-1.285), 1.042 (0.960-1.131), 0.937 (0.861-1.020), 0.911(0.835-0.994), 0.868 (0.786-0.959), and 0.738 (0.670-0.814), respectively (P for trend <0.001). The 6.4% increased MAFLD risk was associated with each preceding year in AAM. The association between AAM and MAFLD was modified by age, ethnicity, and menopause. Early adulthood adiposity partially mediated this association. CONCLUSION: The findings of this study suggest that obesity prevention strategies are needed from young adulthood in women who undergo early menarche to reduce the risk of MAFLD.


Assuntos
Hepatopatias , Hepatopatia Gordurosa não Alcoólica , Feminino , Humanos , Adulto Jovem , Adulto , Menarca , Estudos Transversais , Estudos de Coortes , Fatores Etários , Obesidade/complicações , China/epidemiologia , Hepatopatias/complicações , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/complicações
5.
BMC Public Health ; 23(1): 298, 2023 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-36759796

RESUMO

BACKGROUND: Adiposity is widely recognized as one of the risk factors for high blood pressure (BP) and increasing adiposity is associated with elevated BP. However, which measures of adiposity could be most strongly associated with BP in multi-ethnic population remains uncertain, giving rise to implications that population-based adiposity measures could be necessary. METHODS: 80,000 multi-ethnic adults recruited from 5 provinces across Southwest China during 2018 ~ 2019 were studied. Multiple linear regression was applied to investigate the associations of systolic blood pressure (SBP) with: (1) two measures of general adiposity, body mass index (BMI) and height-adjusted weight; and (2) three measures of central adiposity, waist circumference (WC), hip circumference (HC) and waist hip ratio (WHR). RESULTS: Two distinct population-specific patterns were identified, as "BMI to SBP" and "WC to SBP". 90% of the participants fall into "BMI to SBP" pattern, in which the associations of SBP with BMI were independent of WC, and SBP-WC associations were considerably decreased by adjustment for BMI. And in this pattern, 10 kg/m2 greater BMI was associated with 11.9 mm Hg higher SBP on average. As for the rest population (Han males in Yunnan and Tibetans in Lhasa), they are suited for "WC to SBP" pattern, 10 cm wider WC was associated with 3.4 mm Hg higher SBP. CONCLUSION: Our results indicated that when selecting proper predictors for BP, population-specific adiposity measures are needed, considering ethnicity, sex and residing regions. A better understanding of adiposity and BP may better contribute to the potential clinical practices and developing precision application strategies.


Assuntos
Adiposidade , Hipertensão , Masculino , Humanos , Adulto , Pressão Sanguínea/fisiologia , Adiposidade/fisiologia , População do Leste Asiático , China/epidemiologia , Obesidade/complicações , Hipertensão/etiologia , Circunferência da Cintura , Índice de Massa Corporal , Fatores de Risco
6.
BMC Public Health ; 23(1): 1525, 2023 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-37563625

RESUMO

BACKGROUND: Existing evidence shows that there is an independent correlation between nephrolithiasis and gout, and hyperuricemia is the most important risk factor for gout. However, hyperuricemia was often used as an accompanying symptom of gout to explore its association with nephrolithiasis, there were few studies to explore whether hyperuricemia itself or serum uric acid (SUA) is related to the risk of nephrolithiasis. Evidence on the relationship between hyperuricemia and nephrolithiasis is still insufficient. METHODS: A total of 22,303 participants aged 30 to 79 years who participated in the China Multi-Ethnic Cohort (CMEC) study in Yunnan Province from May 2018 to September 2019 were included in the study. All participants received standardized face-to-face interviews, medical examinations, and biochemical examinations. Logistic regression was used to estimate the association between hyperuricemia and nephrolithiasis, and a restricted cubic spline (RCS) model was used to explore the dose-response relationship between SUA and the risk of nephrolithiasis. RESULTS: 14.5% of all participants were diagnosed with hyperuricemia, and 12.1% were diagnosed with nephrolithiasis. After adjusting for all potential confounders, the OR (95%CI) for nephrolithiasis in participants with hyperuricemia compared with participants without hyperuricemia was 1.464 (1.312,1.633), p < 0.001. Restricted cubic spline regression analysis showed that the risk of nephrolithiasis increased with the increase of SUA, and when the level of SUA is higher than 356 µmol/L in males and higher than 265 µmol/L in females, there is a dose-response relationship between the increase of SUA and the risk of nephrolithiasis in both males and females (p for nonlinearity = 0.1668, p for nonlinearity = 0.0667). CONCLUSION: Asymptomatic hyperuricemia is associated with an increased risk of developing nephrolithiasis. Before reaching the diagnostic criteria for hyperuricemia, the risk of nephrolithiasis rises with the increase in SUA. This suggests that controlling SUA levels may be significant for the prevention of nephrolithiasis.


Assuntos
Gota , Hiperuricemia , Nefrolitíase , Masculino , Feminino , Humanos , Hiperuricemia/complicações , Hiperuricemia/epidemiologia , Ácido Úrico , Estudos Transversais , China/epidemiologia , Gota/complicações , Gota/epidemiologia , Fatores de Risco , Nefrolitíase/epidemiologia , Nefrolitíase/complicações
7.
Acta Radiol ; 64(3): 1155-1165, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35765208

RESUMO

BACKGROUND: Despite its wide adoption in stroke imaging, the diffusion-weighted imaging (DWI) lesion is heterogeneous. The emerging diffusion kurtosis imaging (DKI) has been postulated to resolve the graded DWI lesion. PURPOSE: To determine the perfusion characteristics of the central infarction core, kurtosis/diffusion mismatch, and peripheral regions. MATERIAL AND METHODS: Patients with acute ischemic stroke underwent DWI, DKI, and perfusion-weighted imaging (PWI) scans. The patients were divided into mean kurtosis (MK)/mean diffusivity (MD) match and mismatch groups. Perfusion parameters were measured in the MK/MD lesion and peripheral areas in the MK/MD match group. We also analyzed perfusion status in the MK/MD lesion mismatch area for the mismatch group. RESULTS: A total of 40 eligible patients (24 MK/MD match and 16 MK/MD mismatch) were enrolled in the final data analysis. The MTT and TTP progressively decreased, while the cerebral blood flow (CBF) and cerebral blood volume (CBV) increased from the central to peripheral areas. In addition, CBF in the MK/MD mismatch region was significantly higher than that in the central region (P < 0.05), but similar to the peripheral region. Furthermore, CBV in the MK/MD mismatch region did not differ significantly from that of the central region, but both were significantly lower than that of the peripheral area (P < 0.05). CONCLUSION: The MK/MD mismatch region had blood flow similar to the peripheral region but with a reduced blood volume, indicating that it was less ischemic from the infarction core, albeit insufficient collateral circulation.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/patologia , Isquemia Encefálica/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Doença Aguda , Perfusão , Infarto Cerebral/diagnóstico por imagem , Infarto
8.
Br J Nutr ; 128(11): 2230-2240, 2022 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-35000632

RESUMO

Metabolically healthy obesity (MHO) might be an alternative valuable target in obesity treatment. We aimed to assess whether alternative Mediterranean (aMED) diet and Dietary Approaches to Stop Hypertension (DASH) diet were favourably associated with obesity and MHO phenotype in a Chinese multi-ethnic population. We conducted this cross-sectional analysis using the baseline data of the China Multi-Ethnic Cohort study that enrolled 99 556 participants from seven diverse ethnic groups. Participants with self-reported cardiometabolic diseases were excluded to eliminate possible reverse causality. Marginal structural logistic models were used to estimate the associations, with confounders determined by directed acyclic graph (DAG). Among 65 699 included participants, 11·2 % were with obesity. MHO phenotype was present in 5·7 % of total population and 52·7 % of population with obesity. Compared with the lowest quintile, the highest quintile of DASH diet score had 23 % decreased odds of obesity (OR = 0·77, 95 % CI 0·71, 0·83, Ptrend < 0·001) and 27 % increased odds of MHO (OR = 1·27, 95 % CI 1·10, 1·48, Ptrend = 0·001) in population with obesity. However, aMED diet showed no obvious favourable associations. Further adjusting for BMI did not change the associations between diet scores and MHO. Results were robust to various sensitivity analyses. In conclusion, DASH diet rather than aMED diet is associated with reduced risk of obesity and presents BMI-independent metabolic benefits in this large population-based study. Recommendation for adhering to DASH diet may benefit the prevention of obesity and related metabolic disorders in Chinese population.


Assuntos
Dieta Mediterrânea , Obesidade Metabolicamente Benigna , Humanos , Estudos Transversais , Estudos de Coortes , População do Leste Asiático , Obesidade/prevenção & controle , Fenótipo , Fatores de Risco
9.
Br J Nutr ; 128(6): 1137-1146, 2022 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34605387

RESUMO

Different from developed countries, there is a paucity of research examining how the Dietary Approaches to Stop Hypertension (DASH) and Mediterranean diets relate to lipids in less-developed ethnic minority regions (LEMR). A total of 83 081 participants from seven ethnic groups were retrieved from the baseline data of the China Multi-Ethnic Cohort study, which was conducted in less-developed Southwest China between May 2018 and September 2019. Multivariable linear regression models were then used to examine the associations of the DASH and alternative Mediterranean diet (AMED) scores, assessed by modified DASH score and AMED, as well as their components with total cholesterol (TC), LDL-cholesterol, HDL-cholesterol, TAG and TC/HDL-cholesterol. The DASH scores were negatively associated with TC, HDL-cholesterol and TAG. Comparing the highest quintiles with the lowest DASH scores, TC decreased 0·0708 (95 % CI -0·0923, -0·0493) mmol/l, HDL-cholesterol decreased 0·0380 (95 % CI -0·0462, -0·0299) mmol/l and TAG decreased 0·0668 (95 % CI -0·0994, -0·0341) mmol/l. The AMED scores were negatively associated with TC, LDL-cholesterol and HDL-cholesterol. Comparing the highest quintiles with the lowest AMED scores, TC decreased 0·0816 (95 % CI -0·1035, -0·0597) mmol/l, LDL-cholesterol decreased 0·0297 (95 % CI -0·0477, -0·0118) mmol/l and HDL-cholesterol decreased 0·0275 (95 % CI -0·0358, -0·0192) mmol/l. Although both the DASH diet and the Mediterranean diet were negatively associated with blood lipids, those associations showed different patterns in LEMR, particularly for TAG and HDL-cholesterol.


Assuntos
Dieta Mediterrânea , Abordagens Dietéticas para Conter a Hipertensão , Humanos , Etnicidade , Estudos de Coortes , Minorias Étnicas e Raciais , Grupos Minoritários , Lipídeos , HDL-Colesterol , LDL-Colesterol
10.
BMC Public Health ; 22(1): 118, 2022 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-35038997

RESUMO

BACKGROUND: Little is known about the associations between healthy dietary patterns and metabolic dysfunction-associated fatty liver disease (MAFLD) in less-developed ethnic minority regions (LEMRs), where the prevalence of MAFLD is increasing rapidly and dietary habits are quite different from those in developed countries. Moreover, a significant subset of MAFLD individuals in LEMRs are nonobese, but the efficacy of dietary patterns on MAFLD individuals with different obese statuses is also unclear. We aimed to test the associations of two wildly recommended a priori dietary patterns-Alternate Mediterranean diet (AMED) and Dietary Approaches to Stop Hypertension (DASH)-with the risk of MAFLD in the total population, and further in nonobese and obese individuals. METHODS: We recruited 99,556 participants in the China Multi-Ethnic Cohort Study, an ongoing cohort study in less-developed southwest China. Using validated food frequency questionnaire, each participant was assigned an AMED score and a DASH score. MAFLD was ascertained as hepatic steatosis on ultrasound together with diabetes, overweight/obesity, or two other metabolic risk factors. We performed logistic regression with inverse probability of exposure weighting (IPEW) to examine associations between two dietary patterns and MAFLD, adjusting for potential confounders under the guidance of directed acyclic graphs. Further, analyses were stratified by body mass index. RESULTS: We included 66,526 participants (age 49.5±11.0; 62.6% women), and the prevalence of MAFLD was 16.1%. Participants in the highest quintile of DASH score showed strong inverse associations with risks of MAFLD (OR = 0.85; 95% CI, 0.80-0.91; Ptrend < 0.001) compared with participants in the lowest quintile. The association between DASH and nonobese MAFLD (OR = 0.69; 95% CI, 0.61-0.78; Ptrend < 0.001) was stronger (I2 = 78.5 % ; Pheterogeneity = 0.001) than that with obese MAFLD (OR = 0.90; 95% CI, 0.83-0.98; Ptrend = 0.002). There was a null association between AMED and MAFLD risk. CONCLUSIONS: In LEMRs, a DASH diet but not AMED was associated with MAFLD. The relationship appeared to be more pronounced in nonobese MAFLD individuals than in obese MAFLD individuals.


Assuntos
Dieta Mediterrânea , Hepatopatia Gordurosa não Alcoólica , Adulto , Estudos de Coortes , Estudos Transversais , Minorias Étnicas e Raciais , Etnicidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Grupos Minoritários , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Obesidade/epidemiologia
11.
Medicina (Kaunas) ; 58(9)2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36143871

RESUMO

Background and objectives: The COVID-19 pandemic continues worldwide, and there is no effective treatment to treat it. Chinese medicine is considered the recommended treatment for COVID-19 in China. This study aimed to examine the effectiveness of tetrandrine in treating COVID-19, which is originally derived from Chinese medicine. Materials and Methods: A total of 60 patients, categorized into three types (mild, moderate, severe), from Daye Hospital of Chinese Medicine with a diagnosis of COVID-19 were included in this study. Demographics, medical history, treatment, and results were collected. We defined two main groups according to the clinical outcome between improvement and recovery. All underlying factors including clinical outcomes were assessed in the total number of COVID-19 patients and moderate-type patients. Results: In a total of 60 patients, there were significant differences in the clinical outcome underlying treatment with antibiotics, tetrandrine, and arbidol (p < 0.05). When the comparison was limited to the moderate type, treatment with tetrandrine further increased recovery rate (p = 0.007). However, the difference disappeared, and no association was indicated between the clinical outcome and the treatment with and without antibiotic (p = 0.224) and arbidol (p = 0.318) in the moderate-type patients. In all-type and moderate-type patients, tetrandrine improved the rate of improvement in cough and fatigue on day 7 (p < 0.05). Conclusions: Tetrandrine may improve clinical outcome in COVID-19 patientsand could be a promising potential natural antiviral agent for the prevention and treatment of COVID-19.


Assuntos
Tratamento Farmacológico da COVID-19 , Antibacterianos/uso terapêutico , Antivirais/uso terapêutico , Benzilisoquinolinas , Humanos , Pandemias , SARS-CoV-2 , Resultado do Tratamento
12.
Epilepsy Behav ; 115: 107683, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33360398

RESUMO

PURPOSE: To explore the changes of gamma-aminobutyric acid (GABA) levels in the bilateral hippocampus and anterior cingulate cortex (ACC) of healthy control subjects and patients with temporal lobe epilepsy (TLE) and the correlation of GABA levels with the clinical symptoms by quantitative magnetic resonance spectroscopy (MRS). METHODS: N-acetylaspartate (NAA), creatine (Cr) as well as choline (Cho) and GABA levels in the bilateral hippocampus and ACC were measured in 40 patients with TLE and 26 healthy control (NC) subjects with quantitative Meshcher-Garwood point resolved spectroscopy (MEGA-PRESS). The NAA/(Cho + Cr) and GABA/Cr ratios were compared between the NC and TLE groups. Comparisons were also made between the subgroups with lateralization (left TLE, right TLE and uncertain), short (<10 years) and longer (≥10 years) clinical seizure history (CSH), low (<1/month) and higher (≥1/month) seizure frequency (SF), with and without cognitive impairment (CI) in the patients with TLE, and by antiepileptic medications. Further analyses of the clinical information and metabolite ratios between the patients with TLE with and without CI were preformed. RESULTS: The GABA/Cr ratio was significantly decreased in the bilateral hippocampus (left: P = 0.028, right: P = 0.035), while the NAA/(Cho + Cr) ratio was decreased only in the right hippocampus (RH) (P = 0.004) in patients with TLE compared with that of the NCs. Whereas the NAA/(Cho + Cr) ratio showed a consistent decreasing trend in bilateral hippocampus during the CSH, it only showed a significant difference in the RH. The GABA changes in the hippocampal and ACC regions were not consistent during different stages of the disease. In the bilateral hippocampus, the GABA/Cr ratio was decreased in the short seizure history (<10 years) patients with TLE compared with NCs (left: P = 0.018, right: P = 0.012), whereas the long seizure history (≥10 years) patients with TLE showed no difference with the NCs. However, in the ACC, the GABA/Cr ratio of the CI group was significantly decreased compared with that of NCs (P = 0.015). Further analysis showed that the patients with TLE with CI had obvious atrophy of the gray matter volume (GMV) and total parenchymal brain volume (PBV); GABA/Cr ratio was decreased in ACC, but increased in bilateral hippocampus compared with that of the no cognitive impairment (NOCI) group. CONCLUSION: The GABA/Cr ratio was more valuable than the NAA/(Cho + Cr) ratio in evaluating the dynamic metabolite changes in patients with TLE. Importantly, the GABA changes in the hippocampal and ACC regions were not consistent during different stages of the disease. In the bilateral hippocampus, the GABA/Cr ratio was decreased at the early stage, but recovered to normal levels later. The decreased GABA/Cr ratio in the ACC might indicate more cerebral cortex was involved, resulting in more CI in patients with TLE.


Assuntos
Epilepsia do Lobo Temporal , Ácido Aspártico , Colina , Creatina , Epilepsia do Lobo Temporal/complicações , Epilepsia do Lobo Temporal/diagnóstico por imagem , Giro do Cíngulo/diagnóstico por imagem , Hipocampo/diagnóstico por imagem , Humanos , Ácido gama-Aminobutírico
13.
Nanotechnology ; 31(37): 375603, 2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32460263

RESUMO

Herein, the desorption effect of supercritical CO2 (scCO2) was utilized to obtain sub-5 nm Ag nanoparticles (NPs) with a high Ag loading in SBA-15. The size of the Ag NPs decreased from 3.54 ± 0.79 nm (Ag loading of 25.3 wt.% wt.%) to 2.38 ± 0.68 (Ag loading of 10.5 wt%) nm by changing the depressurization curve from 0.1 MPa min-1 (20-14 MPa) to 3 MPa min-1 (20-12 MPa). Meanwhile, the intensity of the crystalline Ag characteristic peaks was obviously higher than the latter sample from the x-ray diffraction (XRD) patterns. However, compared with the adsorption kinetics of the two precursors of AgNO3 and Cu(NO3)2 on SBA-15, under the same deposition and depressurization conditions, when the two depositional systems used water as a co-solvent, the time taken to reach the adsorption equilibrium of Ag+ on the supports was longer than the time taken by Cu2+, which existed in the water as [Cu(H2O)4]2+. The surface of SBA-15 was hydrophilic, and then the interaction of Ag+ and the surface was weaker compared with Cu2+, making Ag+ highly dispersed on the surface under the scCO2 desorption effect. After calcination, the size of the Ag NPs decreased, but the morphology of CuO was mainly characterized by nanorods (NRs). Moreover, by comparing the experiments of wetness impregnation, the dispersion ability of the bulk scCO2 of the reactor was inefficient for Ag+ adsorbed on the channels in the depressurization process.

14.
Nanotechnology ; 31(9): 095602, 2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-31703220

RESUMO

Here, we present a novel method to control the size of CuO nanoparticles (NPs) and Cu loading in SBA-15 via fast desorption of supercritical CO2 (scCO2). After calcination, the average size of the CuO NPs (6.47 ± 2.89∼2.18 ± 0.97 nm) decreased with the increase of the depressurization rate (20-14 MPa, 50 °C) from transmission electron microscopy, and the x-ray diffraction results also indicated the decrement of the average particle size (8.6∼4.3 nm by a Scherrer equation). Two reduction peaks situated at 195 °C and 220 °C were found from the temperature-programmed reductions with H2 profiles, and the intensity of the low-temperature peak increased with increasing the rate for a profile. The hydrogenation of dimethyl oxalate (DMO) to ethylene glycol (EG) was selected to evaluate the catalytic activity of the as-prepared sample. The reaction was conducted at p = 3.0 MPa, T = 200 °C, H2/DMO = 120, the weight hourly space velocity  = 1.2 h-1, and the EG selectivity remained at about 90% for over 100 h. The fast desorption of scCO2 caused mechanical perturbations and crystallization of the adsorbed salt ions on the supports, decreasing the particle size and increasing Cu loading (8∼12 wt%).

15.
Nanotechnology ; 31(26): 265601, 2020 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-32163939

RESUMO

High quality and high quantity few-layer graphene was successfully prepared using a new impinging jet method. Natural graphite flakes were first agitated in N-methyl pyrrolidone (NMP) with the assistance of supercritical CO2, then the half-exfoliated graphite was further stripped using the shear stress derived from the impinging jets. After the energy conversion and stress analysis of the graphite particles during the whole exfoliation process, it was revealed that the size of the target mesh, the distance between the nozzle and the target, the decompression rate, and the size of the raw materials had a significant influence on the exfoliation process. Additionally, a microscopic view of the exfoliation and dispersion mechanism of graphene in the CO2-NMP system was investigated using molecular dynamics simulation, and CO2 was found to be beneficial for the penetration of NMP into the graphite sheets. Finally, the concentration and quality characteristics of the prepared graphene were characterized using ultraviolet-visible spectroscopy, transmission electron microscopy, Raman spectroscopy, and atomic force microscopy. The maximum concentration was as high as 0.689 mg ml-1, the thickness of 68% of the product was less than 2.5 nm, and the lateral dimension was from 0.5 to 3.0 µm. These results indicate that this impinging jet method is promising for large-scale industrial production.

16.
Int J Neurosci ; 130(4): 391-397, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31721620

RESUMO

Purpose: The aim of this study was to explore the mechanism of neurological changes underlying the toxicity of nicotine.Materials and methods: Rat pheochromocytoma 12 (PC12) cells and human neuroglia (HM) cells were used. The ROS levels of the cells were detected by the FACScan. Autophagy flux was monitored by a tandem monomeric RFP-GFP-tagged LC3 lentivirus. The autophagic proteins LC3, SQSTM1/p62 and Beclin1 were detected by western blot assay. In order to evaluate the effects of nicotine and melatonin on the morphological changes of neurons, primary cortical neurons were obtained and immunocytochemistry of TUBB3 tubulin were conducted.Results: Nicotine increased the levels of reactive oxygen species (ROS) in PC12 and HM cells in a concentration-dependent manner. Microscopy showed increased autophagic flux in nicotine-treated PC12 cells. Subsequent western blotting results showed that nicotine induced increase in the levels of LC3B-II and Beclin1, and decreased SQSTM1/p62 in a concentration-dependent manner. Finally, nicotine treatment reduced the length of TUBB3-positive axons and dendrites. Melatonin, a mitochondrially targeted antioxidant, reduced the ROS level, and blocked autophagy activation and the morphologic structural changes induced by nicotine.Conclusions: Our results suggested that the role of nicotine in neuronal toxicity maybe through the induction of ROS and the subsequent activation of autophagy. These effects could be restored by melatonin.


Assuntos
Autofagia/efeitos dos fármacos , Melatonina/metabolismo , Neuroglia/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Nicotina/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Animais , Relação Dose-Resposta a Droga , Humanos , Camundongos , Neuroglia/metabolismo , Neurônios/metabolismo , Células PC12 , Ratos
17.
Wei Sheng Yan Jiu ; 49(5): 780-784, 2020 Sep.
Artigo em Zh | MEDLINE | ID: mdl-33070824

RESUMO

OBJECTIVE: Investigate the estrogen receptor expression in human thyroid squamous cell carcinoma SW579 and the effects of genistein on the apoptosis and cycle of SW579 and its mechnism. METHODS: The real-time PCR was applied to detect the expression of estrogen receptor(ER)α、ERß and G protein-coupled receptor(GPR)30 in human thyroid squamous cell line SW579; MTT was used to test the effect of genistein on cell proliferation in the SW579 cells before and after blocking GPR30; flow cytometry was explorited to measure the effect of genistein on the cell cycle and apoptosis in the SW579 was detected before and after blocking GPR30. RESULTS: The high concentration of genistein promoted the expression of ERß and GPR30 in the SW579 cells, but ERα was not expressed. The specific blocking of GPR30, the cell proliferation was aboviously inhibited by genistein in the SW579 cells and the cell apoptosis was markedly promoted after the GPR30 was blocked; The cell cycle was mainly blocked in G_2/M phase. CONCLUSION: Genistein can obiviously promote the cell proliferation in the SW579 cells, which may be related to the action of GPR30.


Assuntos
Genisteína , Neoplasias da Glândula Tireoide , Apoptose , Ciclo Celular , Divisão Celular , Linhagem Celular Tumoral , Células Epiteliais , Genisteína/farmacologia , Humanos
18.
Bioprocess Biosyst Eng ; 42(8): 1273-1283, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31041517

RESUMO

High cost and high viscosity of ionic liquid restricted its commercial application in pretreatment of lignocellulose. Water and ethanol were used as additive in [EMIM][OAc] to pretreat corn cob at moderate temperature (< 100 °C). It was found that enzyme hydrolysis (EH) sugar yield was increased with the increase of IL content. The largest EH sugar yield of 68.8% was obtained when pure IL was used. However, for [EMIM][OAc]/ethanol, the EH sugar yield as high as 66.9% was gained when the IL content was 80%, which was comparable to that for pure IL pretreatment. In addition, Kamlet-Taft parameter was calculated to characterize the polarity solvency of binary liquid phase, to illustrate the underlying reason for the increase of EH sugar and the lignin removal. Finally, to demonstrate the crystalline and microstructure change after pretreatment, XRD and SEM were performed for the raw materials and the pretreated samples.


Assuntos
Celulase/química , Etanol/sangue , Líquidos Iônicos/química , Lignina/química , Água/química , Zea mays/química , Hidrólise
19.
Radiology ; 287(2): 651-657, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29558293

RESUMO

Purpose To determine the relationship between diffusion-weighted imaging (DWI) and diffusion kurtosis imaging (DKI) in patients with acute stroke at admission and the tissue outcome 1 month after onset of stroke. Materials and Methods Patients with stroke underwent DWI (b values = 0, 1000 sec/mm2 along three directions) and DKI (b values = 0, 1000, 2000 sec/mm2 along 20 directions) within 24 hours after symptom onset and 1 month after symptom onset. For large lesions (diameter ≥ 1 cm), acute lesion volumes at DWI and DKI were compared with those at follow-up T2-weighted imaging by using Spearman correlation analysis. For small lesions (diameter < 1 cm), the number of acute lesions at DWI and DKI and follow-up T2-weighted imaging was counted and compared by using the McNemar test. Results Thirty-seven patients (mean age, 58 years; range, 35-82 years) were included. There were 32 large lesions and 138 small lesions. For large lesions, the volumes of acute lesions on kurtosis maps showed no difference from those on 1-month follow-up T2-weighted images (P = .532), with a higher correlation coefficient than those on the apparent diffusion coefficient and mean diffusivity maps (R2 = 0.730 vs 0.479 and 0.429). For small lesions, the number of acute lesions on DKI, but not on DWI, images was consistent with that on the follow-up T2-weighted images (P = .125). Conclusion DKI complements DWI for improved prediction of outcome of acute ischemic stroke. © RSNA, 2018.


Assuntos
Isquemia Encefálica/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Acidente Vascular Cerebral/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Isquemia Encefálica/fisiopatologia , Imagem de Difusão por Ressonância Magnética/instrumentação , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Seguimentos , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Reconhecimento Automatizado de Padrão , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Estudos Retrospectivos , Acidente Vascular Cerebral/patologia
20.
Wei Sheng Yan Jiu ; 47(6): 984-992, 2018 Nov.
Artigo em Zh | MEDLINE | ID: mdl-30593333

RESUMO

OBJECTIVE: To study the effect and mechanism of genistein on the proliferation, adhesion, invasion and migration of SW579 cells. METHODS: MTT assay was used to detect the effect of genistein on cell proliferation of the thyroid carcinoma cell line( SW579). Cell-matrix adhesion and transwell invasion assay were used to measure the impact of genistein on the cell adhesion, invasion and migration. Real-time PCR assay was used to detect the effect of genistein on the level of MMP2 mRNA. RESULTS: Compared with the control groups, genistein treated groups can significantly promote the proliferation of SW579 cells. However, genistein can obiviously inhibited the adhesion, invasion and migartion of SW579 cells. And genistein can dramatically decreased MMP2 mRNA expression in SW579 cells. CONCLUSION: In the study, genistein could effectively inhibit the invasion and migration ability of the SW579 cells in vitro, and the reduction of MMP-2 expression may play an important role in this process.


Assuntos
Anticarcinógenos/farmacologia , Carcinoma de Células Escamosas , Genisteína , Neoplasias da Glândula Tireoide , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Genisteína/farmacologia , Humanos , Invasividade Neoplásica , Neoplasias da Glândula Tireoide/patologia
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