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1.
Front Microbiol ; 15: 1376844, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39015741

RESUMEN

In nature, methylmercury (MeHg) is primarily generated through microbial metabolism, and the ability of bacteria to methylate Hg(II) depends on both bacterial properties and environmental factors. It is widely known that, as a metabolic analog, molybdate can inhibit the sulfate reduction process and affect the growth and methylation of sulfate-reducing bacteria (SRB). However, after it enters the cell, molybdate can be involved in various intracellular metabolic pathways as a molybdenum cofactor; whether fluctuations in its concentration affect the growth and methylation of aerobic mercury methylating strains remains unknown. To address this gap, aerobic γ-Proteobacteria strains Raoultella terrigena TGRB3 (B3) and Pseudomonas putida TGRB4 (B4), as well as an obligate anaerobic δ-Proteobacteria strain of the SRB Desulfomicrobium escambiense CGMCC 1.3481 (DE), were used as experimental strains. The growth and methylation ability of each strain were analyzed under conditions of 500 ng·L-1 Hg(II), 0 and 21% of oxygen, and 0, 0.25, 0.50, and 1 mM of MoO4 2-. In addition, in order to explore the metabolic specificity of aerobic strains, transcriptomic data of the facultative mercury-methylated strain B3 were further analyzed in an aerobic mercuric environment. The results indicated that: (a) molybdate significantly inhibited the growth of DE, while B3 and B4 exhibited normal growth. (b) Under anaerobic conditions, in DE, the MeHg content decreased significantly with increasing molybdate concentration, while in B3, MeHg production was unaffected. Furthermore, under aerobic conditions, the MeHg productions of B3 and B4 were not influenced by the molybdate concentration. (c) The transcriptomic analysis showed several genes that were annotated as members of the molybdenum oxidoreductase family of B3 and that exhibited significant differential expression. These findings suggest that the differential expression of molybdenum-binding proteins might be related to their involvement in energy metabolism pathways that utilize nitrate and dimethyl sulfoxide as electron acceptors. Aerobic bacteria, such as B3 and B4, might possess distinct Hg(II) biotransformation pathways from anaerobic SRB, rendering their growth and biomethylation abilities unaffected by molybdate.

2.
J Neurol ; 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38869825

RESUMEN

Stroke can lead to cardiac complications such as arrhythmia, myocardial injury, and cardiac dysfunction, collectively termed stroke-heart syndrome (SHS). These cardiac alterations typically peak within 72 h of stroke onset and can have long-term effects on cardiac function. Post-stroke cardiac complications seriously affect prognosis and are the second most frequent cause of death in patients with stroke. Although traditional vascular risk factors contribute to SHS, other potential mechanisms indirectly induced by stroke have also been recognized. Accumulating clinical and experimental evidence has emphasized the role of central autonomic network disorders and inflammation as key pathophysiological mechanisms of SHS. Therefore, an assessment of post-stroke cardiac dysautonomia is necessary. Currently, the development of treatment strategies for SHS is a vital but challenging task. Identifying potential key mediators and signaling pathways of SHS is essential for developing therapeutic targets. Therapies targeting pathophysiological mechanisms may be promising. Remote ischemic conditioning exerts protective effects through humoral, nerve, and immune-inflammatory regulatory mechanisms, potentially preventing the development of SHS. In the future, well-designed trials are required to verify its clinical efficacy. This comprehensive review provides valuable insights for future research.

3.
Crit Care ; 28(1): 5, 2024 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-38167175

RESUMEN

BACKGROUND: Acute ischemic stroke (AIS) complicating an acute myocardial infarction (AMI) is not uncommon, but can severely worsen the clinical prognosis. This study aimed to investigate whether remote ischemic conditioning (RIC) could provide clinical benefits to patients with AIS complicating AMI. METHODS: Subjects with AIS complicating AMI were recruited in this double-blind, randomized, controlled trial; assigned to the RIC and sham groups; and respectively underwent twice daily RIC and sham RIC for 2 weeks. All subjects received standard medical therapy. The primary endpoint was the rate of major adverse cardiac and cerebrovascular events (MACCEs) within 3 months after enrollment. MACCEs comprise of death from all causes, unstable anginas, AMI, acute ischemic strokes, and transient ischemic attacks. RESULTS: Eighty subjects were randomly assigned; 37 patients in the RIC group and 40 patients in the sham-RIC group completed the 3-month follow-up and were included in the final analysis. Both RIC and sham RIC procedures were well tolerated. At 3-month follow-up, 11 subjects (29.7%) in the RIC group experienced MACCEs compared to 21 (52.5%) in the sham group (hazard ratio [HR], 0.396; 95% confidence interval, 0.187-0.838; adjusted p < 0.05). Six subjects (16.2%) in the RIC group had died at the 3-month follow up, significantly lower than the 15 (37.5%) deaths in the sham group (adjusted HR 0.333; 95% CI 0.126-0.881; p = 0.027). Seventeen subjects (45.9%) in the RIC group and 6 subjects (15.0%) in the sham group achieved functional independence (mRS score ≤ 2) at 3-month follow-up (adjusted OR 12.75; 95% CI 2.104-77.21; p = 0.006). CONCLUSIONS: Among patients with acute ischemic stroke complicating acute myocardial infarction, treatment with remote ischemic conditioning decreased the major adverse cardiac and cerebrovascular events and improved functional outcomes at 90 days. TRIAL REGISTRATION: URL: www. CLINICALTRIALS: gov . Unique identifier: NCT03868007. Registered 8 March 2019.


Asunto(s)
Accidente Cerebrovascular Isquémico , Infarto del Miocardio , Accidente Cerebrovascular , Humanos , Infarto del Miocardio/complicaciones , Infarto del Miocardio/terapia , Método Doble Ciego , Resultado del Tratamiento , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/terapia
4.
J Org Chem ; 89(1): 373-378, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38096478

RESUMEN

A highly efficient and regioselective method for constructing functionalized conjugated enals via the Tf2O-mediated tandem reaction of enaminones with thiophenols has been described. Chain products with excellent stereoselectivity could be obtained through substrate regulation. Additionally, a feasible method for synthesizing ß-naphthalaldehydes through PhSO2Na/DABCO promoting hydrogen atom transfer process has also been reported here. Mechanism studies have shown that 2-formyl vinyl triflate 8 and sulfonylated enal 9 were the key intermediates in this process.

5.
J Cereb Blood Flow Metab ; 43(12): 2049-2059, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37668997

RESUMEN

A proportion of acute ischemic stroke (AIS) patients suffer from early neurological deterioration (END) within 24 hours following intravenous thrombolysis (IVT), which greatly increases the risk of poor prognosis of these patients. Therefore, we aimed to explore the predictors of early neurological deterioration of ischemic origin (ENDi) in AIS patients after IVT and develop a nomogram prediction model. This study collected 244 AIS patients with post-thrombolysis ENDi as the derivation cohort and 155 patients as the validation cohort. To establish a nomogram prediction model, risk factors were identified by multivariate logistic regression analysis. The results showed that neutrophil to lymphocyte ratio (NLR) (OR 2.616, 95% CI 1.640-4.175, P < 0.001), mean platelet volume (MPV) (OR 3.334, 95% CI 1.351-8.299, P = 0.009), body mass index (BMI) (OR 1.979, 95% CI 1.285-3.048, P = 0.002) and atrial fibrillation (AF) (OR 8.012, 95% CI 1.341-47.873, P = 0.023) were significantly associated with ENDi. The area under the curve of the prediction model constructed from the above four factors was 0.981 (95% CI 0.961-1.000) and the calibration curve was close to the ideal diagonal line. Therefore, this nomogram prediction model exhibited good discrimination and calibration power and might be a reliable and easy-to-use tool to predict post-thrombolysis ENDi in AIS patients.


Asunto(s)
Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Accidente Cerebrovascular/terapia , Fibrinolíticos/efectos adversos , Accidente Cerebrovascular Isquémico/complicaciones , Isquemia Encefálica/complicaciones , Terapia Trombolítica/efectos adversos , Terapia Trombolítica/métodos
6.
World J Gastrointest Surg ; 15(8): 1564-1573, 2023 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-37701697

RESUMEN

Transjugular intrahepatic portosystemic shunt (TIPS) is an established procedure for treating the complications of portal hypertension in liver cirrhosis. While the pathogenesis of postoperative TIPS-related hepatic encephalopathy (HE) has yet to be fully understood, intraoperative portosystemic shunts may provide a pathological basis for the occurrence of postoperative HE in patients with liver cirrhosis. Studies at home and abroad have expressed mixed opinions about TIPS-related HE. This study presents a literature review on the risk factors for and prevention and treatment of perioperative TIPS-related HE in patients with liver cirrhosis, aiming to optimize the procedure and reduce the incidence of postoperative HE.

7.
Int J Rheum Dis ; 25(11): 1339-1342, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36320146

RESUMEN

Systemic sclerosis (SSc) is a chronic autoimmune disease characterized by microangiopathy, extensive fibrosis and autoantibody production. It is generally believed that microvascular disease is the hallmark of SSc. Macrovascular involvement is not initially considered as a feature of SSc, but its mortality is high, which should not be ignored. Up to the present, SSc patients with cerebral involvement and multiple macrovascular stenosis have been rarely described. We herein report a case of cerebral infarction and severe stenosis of the internal carotid artery and coronary artery associated with SSc.


Asunto(s)
Arteria Carótida Interna , Esclerodermia Sistémica , Humanos , Vasos Coronarios , Constricción Patológica/complicaciones , Esclerodermia Sistémica/complicaciones , Infarto Cerebral/complicaciones
8.
Front Neurol ; 13: 1004264, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36408516

RESUMEN

Objectives: Statins either barely affect or increase lipoprotein(a) [Lp(a)] levels. This study aimed to explore the factors correlated to the change of Lp(a) levels as well as the relationship between Lp(a) and the recurrent vascular events in statin-treated patients with first acute ischemic stroke (AIS). Methods: Patients who were admitted to the hospital with first AIS from October 2018 to September 2020 were eligible for inclusion. Correlation between the change of Lp(a) levels and potential influencing factors was assessed by linear regression analysis. Cox proportional regression models were used to estimate the association between Lp(a) and recurrent vascular events including AIS, transient ischemic attack, myocardial infarction and coronary revascularization. Results: In total, 303 patients, 69.6% males with mean age 64.26 ± 11.38 years, completed the follow-up. During the follow-up period, Lp(a) levels increased in 50.5% of statin-treated patients and the mean percent change of Lp(a) levels were 14.48% (95% CI 6.35-22.61%). Creatinine (ß = 0.152, 95% CI 0.125-0.791, P = 0.007) and aspartate aminotransferase (AST) (ß = 0.160, 95% CI 0.175-0.949, P = 0.005) were positively associated with the percent change of Lp(a) levels. During a median follow-up of 26 months, 66 (21.8%) patients had a recurrent vascular event. The median time period between AIS onset and vascular events recurrence was 9.5 months (IQR 2.0-16.3 months). The on-statin Lp(a) level ≥70 mg/dL (HR 2.539, 95% CI 1.076-5.990, P = 0.033) and the change of Lp(a) levels (HR 1.003, 95% CI 1.000-1.005, P = 0.033) were associated with the recurrent vascular events in statin-treated patients with first AIS. Furthermore, the on-statin Lp(a) levels ≥70 mg/dL (HR 3.612, 95% CI 1.018-12.815, P = 0.047) increased the risk of recurrent vascular events in patients with low-density lipoprotein cholesterol (LDL-C) levels < 1.8 mmol/L. Conclusions: Lp(a) levels increased in half of statin-treated patients with first AIS. Creatinine and AST were positively associated with the percent change of Lp(a) levels. Lp(a) is a determinant of residual vascular risk and the change of Lp(a) is positively associated with the risk of recurrent vascular events in these patients.

9.
J Stroke Cerebrovasc Dis ; 31(7): 106538, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35523054

RESUMEN

OBJECTIVES: Hemorrhagic transformation (HT) is a frequent and severe complication of ischemic stroke. This study aimed to evaluate the factors associated with the occurrence of HT in patients with acute cerebellar infarction. MATERIALS AND METHODS: A total of 190 patients, 141 male (74.2%) and 49 female (25.8%) with mean age 61.84 ± 12.16 years, who were admitted within 72 h of acute cerebellar infarction onset from January 2017 to March 2021 were retrospectively recruited. The multivariate logistic regression analysis was used to evaluate the independent influent factors for HT and receiver-operating characteristic (ROC) curve was applied to calculate the predictive value of those factors for HT in patients with acute cerebellar infarction. RESULTS: 37 out of 190 recruited patients (19.47%) had HT within 14 days after acute cerebellar infarction onset. The incidence rates of HT occurring within 3 days, 3-7 days and 7-14 days were 13.5%, 40.5% and 45.9%, respectively. Results of the multivariable logistic regression analysis indicated that atrial fibrillation (AF) (OR 6.196, 95% CI 1.357-28.302, P = 0.019), infarct diameter (OR 5.813, 95% CI 2.932-11.526, P < 0.001), white matter hyperintensity (WMH) (OR 2.44, 95% CI 1.134-5.252, P = 0.023) were independent risk factors for HT in acute cerebellar infarction, while lymphocyte count (OR 0.319, 95% CI 0.142-0.716, P = 0.006) showed an independently protective effect. CONCLUSIONS: Infarct diameter, AF and WMH are independent risk factors for HT in patients with acute cerebellar infarction, while the lymphocyte count is a protective factor.


Asunto(s)
Fibrilación Atrial , Isquemia Encefálica , Enfermedades Cerebelosas , Leucoaraiosis , Accidente Cerebrovascular , Anciano , Fibrilación Atrial/complicaciones , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/epidemiología , Isquemia Encefálica/complicaciones , Enfermedades Cerebelosas/complicaciones , Hemorragia Cerebral/epidemiología , Femenino , Humanos , Infarto/complicaciones , Leucoaraiosis/complicaciones , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Accidente Cerebrovascular/complicaciones
10.
Foods ; 10(11)2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-34828928

RESUMEN

In order to improve the quality of the gluten free rice bread (GFRB), pre-gelatinised rice flour (PGRF) was made and used to partially replace natural rice flour in the production of GFRB. The pre-gelatinisation parameters were optimised and the effects of PGRF on the quality of the GFRB and its batter were studied. The results showed that optimal PGRF was obtained when 50% total water was mixed with 1.0% rice flour and the mixture heated at 80 °C for 2 min. Supplementation with PGRF significantly improved the properties of GFRB by affecting its baking properties, textural properties, colour, and crumb grain features. Effects of PGRF on GFRB were mainly caused by the more closely packed gel structure of rice starch in the bread batter, the higher onset temperature during gelatinisation and the complex effect of PGRF on water-binding capacity in bread batter during the baking process. As the pre-gelatinisation parameters of flours and their effect on gluten-free baked products varied with grain variety, processing properties should be studied before using them, and emphasis should be placed on new techniques such as flour pre-gelatinisation to obtain gluten-free foods with improved quality.

11.
Artículo en Inglés | MEDLINE | ID: mdl-34682469

RESUMEN

The health and welfare of older adults have raised increasing attention due to global aging. Cycling is a physical activity and mode of transportation to enhance the mobility and quality of life among older adults. Nevertheless, the planning strategies to promote cycling among older adults are underutilized. Therefore, this paper describes the nonlinear associations of the built environment with cycling frequency among older adults. The data were collected from the Zhongshan Household Travel Survey (ZHTS) in 2012. The modeling approach was the eXtreme Gradient Boosting (XGBoost) model. The findings demonstrated that nonlinear relationships exist among all the selected built environment attributes. Within specific intervals, the population density, the land-use mixture, the distance from home to the nearest bus stop, and the distance from home to CBD are positively correlated to the cycling among older adults. Additionally, an inverse "U"-shaped relationship appears in the percentage of green space land use among all land uses. Moreover, the intersection density is inversely related to the cycling frequency among older adults. These findings provide nuanced and appropriate guidance for establishing age-friendly neighborhoods.


Asunto(s)
Entorno Construido , Planificación Ambiental , China , Calidad de Vida , Características de la Residencia , Transportes , Caminata
12.
Artículo en Inglés | MEDLINE | ID: mdl-34574517

RESUMEN

Global aging has raised increasing concerns on the health and well-being of older adults. Public transport is a viable option to improve the mobility and quality of life among older adults. However, policies that promote the public transport use among older adults are rare. This study utilizes the eXtreme Gradient Boosting (XGBoost) decision tree to explore the non-linear associations of the built and social environment with bus use among older adults in China. The bus use of older adults was obtained from the Zhongshan Household Travel Survey (ZHTS) in 2012. Results show that non-linear relationships exist among all built environment and social environment characteristics. Within certain thresholds, the percentage of green space land use, land use mixture, bus-stop density, and dwelling unit density are positively related to bus use among older adults. Likewise, one social environment variable, the proportion of older adults in a neighborhood, is the key social environment variable. Furthermore, the dwelling unit density and proportion of older adults appear to have an inverse U-shaped relationship. Additionally, age, ownership of motorcycles, and distance from home to the nearest bus stop also show non-linearity. The findings presented in this paper facilitate effective planning interventions to promote bus use among older adults.


Asunto(s)
Entorno Construido , Calidad de Vida , China , Planificación Ambiental , Características de la Residencia , Medio Social
13.
Front Public Health ; 9: 686144, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34422746

RESUMEN

Aim: Promoting walking activity is an effective way to improve the health of older adults. Walking frequency is a critical component of walking behavior and an essential determinant of daily walking levels. To decipher the association between the built environment and walking frequency among older adults, this study's aims are as follows: (1) to empirically test whether non-linear relationships between the two exist, and (2) to identify the thresholds of the built environment characteristics that promote walking. Methods: The walking frequency of old adults was derived from the Zhongshan Household Travel Survey (ZHTS) in 2012. The sample size of old adults aged 60 or over was 4784 from 274 urban and rural neighborhoods. A semi-parametric generalized additive model (GAMM) is used to analyze the non-linear or non-monotonic relationships between the built environment and the walking frequency among older adults. Results: We found that non-linear relationships exist among five out of the six built environment characteristics. Within certain thresholds, the population density, sidewalk density, bus stop density, land use mixture, and the percentage of green space are positively related to older adults' walking trips. Furthermore, the land use mixture and the percentage of green space show an inverse "V"-shaped relationship. Conclusions: Built environment features can either support or hinder the walking frequency among older adults. The findings in the current study contribute to effective land use and transport policies for promoting active travel among older adults.


Asunto(s)
Entorno Construido , Caminata , China , Planificación Ambiental , Características de la Residencia
14.
Radiol Med ; 126(9): 1149-1158, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34105102

RESUMEN

PURPOSE: This study aimed to explore the impact of different acquisition times on the evaluation of liver function levels in chronic hepatitis B using Gd-EOB-DTPA-enhanced T1 positioning technology under 3.0 Tesla magnetic resonance imaging (MRI). METHODS: A total of 146 patients with chronic hepatitis B (CHB) were classified into four groups as follows: chronic hepatitis B without liver cirrhosis (CH, 22 cases), liver cirrhosis with Child-Pugh classification A (LCA 63 cases), Child-Pugh B (LCB 47 cases) and Child-Pugh C (LCC 14 cases). Normal liver function (NLF) group was composed of 23 persons who had healthy liver and no medical histories of hepatitis. T1 mapping images were performed before and after administration of Gd-EOB-DPTA using Look-Locker sequence. Changes in T1 relaxation time (T1rt), the reduction rate of T1 relaxation time (ΔT1) and the increase in T1 relaxation rate (ΔR1) of liver over time (at 5, 10, 15 and 20 min) were investigated and compared among all five groups using a one-way analysis of variance (ANOVA). The Spearman's rank correlation coefficient (r) was used to show the correlations of these parameters in different liver function groups. RESULTS: In the NLF, CH, LCA and LCB groups, postT1 gradually decreased, while the ΔT1 and ΔR1 gradually increased with time. The parameters were compared between different liver function levels at the same time point, and the differences were statistically significant except for NLF-CH, NLF-LCA and CH-LCA. There was no significant difference in the area under the ROC curve of other parameters at 10, 15 and 20 min. At each time point, no correlation was found between preT1rt and the degrees of liver function. PostT1rt was positively correlated with liver function classification, while ΔT1 and ΔR1 were negatively correlated with liver function classification. CONCLUSION: Gd-EOB-DTPA-enhanced T1 mapping magnetic resonance imaging is beneficial to assess liver function. Using the Gd-EOB-DTPA to enhance T1 mapping imaging to assess liver function can shorten the observation time of the hepatobiliary period and 10 min after enhancement may be the best time point.


Asunto(s)
Medios de Contraste , Gadolinio DTPA , Hepatitis B Crónica/diagnóstico por imagen , Hígado/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Adulto , Análisis de Varianza , Estudios de Factibilidad , Femenino , Hepatitis B Crónica/fisiopatología , Humanos , Hígado/fisiología , Hígado/fisiopatología , Cirrosis Hepática/diagnóstico por imagen , Cirrosis Hepática/fisiopatología , Pruebas de Función Hepática , Masculino , Persona de Mediana Edad , Curva ROC , Valores de Referencia , Sensibilidad y Especificidad
15.
IEEE Trans Cybern ; 51(3): 1286-1299, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31581108

RESUMEN

Multisensor systems are widely applied to realize the comprehensive monitoring and control as they feature multiple individual sensors/outputs. In such systems, different sensors can receive different types of operation signals, such as pressure, temperature, and volume. The desired references for different sensors may conflict in that an input signal that can precisely track all references simultaneously does not exist yet. This gap has motivated us to consider the incompatible multiobjective tracking problem for multisensor systems with random process disturbances and measurement noises. Our primary approach is to solve the problem as a weighted optimization problem using iterative learning control (ILC). First, the best achievable trajectory based on multiple references, as well as the weighted optimal tracking index, is carefully defined and then the ILC algorithms with both fixed and decreasing steps are proposed to generate the input sequence. The output driven by the proposed algorithms has been strictly proven to converge to the best achievable trajectory in both the mean square and almost-sure senses. Extensions to a networked implementation, in which the networks between the sensors and the learning controller suffer random data dropouts, are also detailed. Illustrative simulations are provided to verify the theoretical results.

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