Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 21
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
Angiology ; : 33197241241790, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38532622

RESUMEN

Deep vein thrombosis (DVT) is an important complication of stroke. As coronavirus disease 2019 (COVID-19) enters the stage of persistent and long-term management, the clinical management of DVT in stroke patients may require adjustment. The present study evaluated whether there was an increased risk of DVT in stroke patients during the COVID-19 period. Furthermore, we analyzed the possible risk factors and developed an easy-to-use nomogram to predict DVT in stroke patients during the long-term management of COVID-19. A total of 7087 stroke patients during the COVID-19 period and 14,174 patients with age, sex, and National Institutes of Health Stroke Scale (NIHSS) scores matched before the period from four centers were included. The incidence of DVT in stroke patients during the COVID-19 period (20.5%) was significantly higher than that before this period (15.9%, P < .001). Age, body mass index, smoking, D-dimer, physical activity level, NIHSS score, and intermittent pneumatic compression were significant predictors of DVT during the COVID-19 period (P < .05). A nomogram was constructed; internal and external validations showed high accuracy, and decision curve analysis showed excellent clinical applicability. This nomogram could evaluate the risk of DVT after stroke and assist in its early prevention during the long-term management of COVID-19.

2.
J Agric Food Chem ; 72(12): 6236-6249, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38484389

RESUMEN

Hypercholesterolemia poses a significant cardiovascular risk, particularly in postmenopausal women. The anti-hypercholesterolemic properties of Lactiplantibacillus plantarum ATCC8014 (LP) are well recognized; however, its improving symptoms on postmenopausal hypercholesterolemia and the possible mechanisms have yet to be elucidated. Here, we utilized female ApoE-deficient (ApoE-/-) mice undergoing bilateral ovariectomy, fed a high-fat diet, and administered 109 colony-forming units (CFU) of LP for 13 consecutive weeks. LP intervention reduces total cholesterol (TC) and triglyceride (TG) accumulation in the serum and liver and accelerates their fecal excretion, which is mainly accomplished by increasing the excretion of fecal secondary bile acids (BAs), thereby facilitating cholesterol conversion. Correlation analysis revealed that lithocholic acid (LCA) is an important regulator of postmenopausal lipid abnormalities. LP can reduce LCA accumulation in the liver and serum while enhancing its fecal excretion, accomplished by elevating the relative abundances of Allobaculum and Olsenella in the ileum. Our findings demonstrate that postmenopausal lipid dysfunction is accompanied by abnormalities in BA metabolism and dysbiosis of the intestinal microbiota. LP holds therapeutic potential for postmenopausal hypercholesterolemia. Its effectiveness in ameliorating lipid dysregulation is primarily achieved through reshaping the diversity and abundance of the intestinal microbiota to correct BA abnormalities.


Asunto(s)
Microbioma Gastrointestinal , Hipercolesterolemia , Lactobacillus plantarum , Humanos , Femenino , Ratones , Animales , Hipercolesterolemia/metabolismo , Ácidos y Sales Biliares/metabolismo , Posmenopausia , Colesterol/metabolismo , Lactobacillus plantarum/metabolismo , Hígado/metabolismo , Apolipoproteínas E/metabolismo , Ratones Endogámicos C57BL , Dieta Alta en Grasa
3.
Behav Sci (Basel) ; 14(2)2024 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-38392443

RESUMEN

Natural speech plays a pivotal role in communication and interactions between human beings. The prosody of natural speech, due to its high ecological validity and sensitivity, has been acoustically analyzed and more recently utilized in machine learning to identify individuals with autism spectrum disorders (ASDs). In this meta-analysis, we evaluated the findings of empirical studies on acoustic analysis and machine learning techniques to provide statistically supporting evidence for adopting natural speech prosody for ASD detection. Using a random-effects model, the results observed moderate-to-large pooled effect sizes for pitch-related parameters in distinguishing individuals with ASD from their typically developing (TD) counterparts. Specifically, the standardized mean difference (SMD) values for pitch mean, pitch range, pitch standard deviation, and pitch variability were 0.3528, 0.6744, 0.5735, and 0.5137, respectively. However, the differences between the two groups in temporal features could be unreliable, as the SMD values for duration and speech rate were only 0.0738 and -0.0547. Moderator analysis indicated task types were unlikely to influence the final results, whereas age groups showed a moderating role in pooling pitch range differences. Furthermore, promising accuracy rates on ASD identification were shown in our analysis of multivariate machine learning studies, indicating averaged sensitivity and specificity of 75.51% and 80.31%, respectively. In conclusion, these findings shed light on the efficacy of natural prosody in identifying ASD and offer insights for future investigations in this line of research.

4.
Plants (Basel) ; 12(24)2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38140462

RESUMEN

The plant rhizosphere underlies the crosstalk between plant and soil and has a crucial role in plant growth and development under various environments. We examined the effect of temperature rise on the rhizosphere environment of soybean roots to clarify the rhizosphere crosstalk between roots and soil in response to warm temperature rises in a global warming background. The in situ results of root enzyme activity revealed that soybean roots secrete ß-glucosidase, and enzyme spectrum imaging demonstrated different enzymatic activities under different temperature environments. The soil enzyme kinetics results showed that soil enzymatic activity increased with increasing temperature, and soybean rhizosphere soil enzymatic activity was higher than that of non-rhizosphere soil. Rhizosphere soil and non-rhizosphere soil showed that the dominant bacterial phylum in soybean rhizosphere soil was Acidobacteria, and the dominant bacterial genus was JG30-KF-AS9. Compared with non-rhizosphere soil, rhizosphere soil was more nutrient-rich, and root secretions provided abundant carbon sources and other nutrients for soil microorganisms in the rhizosphere. Rhizosphere microorganisms affect plant growth by influencing the decomposition of soil organic carbon. The organic carbon content of rhizosphere soil was higher than that of non-rhizosphere soil under high temperatures.

5.
Mol Brain ; 16(1): 80, 2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-37986006

RESUMEN

Cognitive dysfunction increases as menopause progresses. We previously found that estrogen receptors (ERs) contribute to dyslipidemia, but the specific relationship between ERs, dyslipidemia and cognitive dysfunction remains poorly understood. In the present study, we analyzed sequencing data from female hippocampus and normal breast aspirate samples from normal and Alzheimer's disease (AD) women, and the results suggest that abnormal ERs signaling is associated with dyslipidemia and cognitive dysfunction. We replicated a mouse model of dyslipidemia and postmenopausal status in LDLR-/- mice and treated them with ß-estradiol or simvastatin, and found that ovariectomy in LDLR-/- mice led to an exacerbation of dyslipidemia and increased hippocampal apoptosis and cognitive impairment, which were associated with reduced estradiol levels and ERα, ERß and GPER expression. In vitro, a lipid overload model of SH-SY-5Y cells was established and treated with inhibitors of ERs. ß-estradiol or simvastatin effectively attenuated dyslipidemia-induced neuronal apoptosis via upregulation of ERs, whereas ERα, ERß and GPER inhibitors together abolished the protective effect of simvastatin on lipid-induced neuronal apoptosis. We conclude that decreased estrogen and its receptor function in the postmenopausal stage promote neuronal damage and cognitive impairment by exacerbating dyslipidemia, and that estrogen supplementation or lipid lowering is an effective way to ameliorate hippocampal damage and cognitive dysfunction via upregulation of ERs.


Asunto(s)
Disfunción Cognitiva , Receptor alfa de Estrógeno , Humanos , Ratones , Femenino , Animales , Receptor alfa de Estrógeno/metabolismo , Receptor beta de Estrógeno/metabolismo , Posmenopausia , Estrógenos/farmacología , Estradiol/farmacología , Disfunción Cognitiva/complicaciones , Simvastatina/farmacología , Simvastatina/uso terapéutico , Lípidos
6.
Hum Genomics ; 17(1): 87, 2023 09 26.
Artículo en Inglés | MEDLINE | ID: mdl-37752570

RESUMEN

OBJECTIVES: In clinical practice, digestive symptoms such as nausea, vomiting are frequently observed in COVID-19 patients. However, the causal relationship between COVID-19 and digestive diseases remains unclear. METHODS: We extracted single nucleotide polymorphisms associated with the severity of COVID-19 from summary data of genome-wide association studies. Summary statistics of common digestive diseases were primarily obtained from the UK Biobank study and the FinnGen study. Two-sample Mendelian randomization analyses were then conducted using the inverse variance-weighted (IVW), Mendelian randomization-Egger regression (MR Egger), weighted median estimation, weighted mode, and simple mode methods. IVW served as the primary analysis method, and Multivariable Mendelian randomization analysis was employed to explore the mediating effect of body mass index (BMI) and type 2 diabetes. RESULTS: MR analysis showed that a causal association between SARS-CoV-2 infection (OR = 1.09, 95% CI 1.01-1.18, P = 0.03), severe COVID-19 (OR = 1.02, 95% CI 1.00-1.04, P = 0.02), and COVID-19 hospitalization (OR = 1.04, 95% CI 1.01-1.06, P = 0.01) with gastroesophageal reflux disease (GERD). Mediation analysis indicated that body mass index (BMI) served as the primary mediating variable in the causal relationship between SARS-CoV-2 infection and GERD, with BMI mediating 36% (95% CI 20-53%) of the effect. CONCLUSIONS: We found a causal relationship between SARS-CoV-2 infection and gastroesophageal reflux disease. Furthermore, we found that the causal relationship between SARS-CoV-2 infection and GERD is mainly mediated by BMI.


Asunto(s)
COVID-19 , Diabetes Mellitus Tipo 2 , Reflujo Gastroesofágico , Humanos , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/genética , Estudio de Asociación del Genoma Completo , Análisis de la Aleatorización Mendeliana , COVID-19/complicaciones , COVID-19/genética , SARS-CoV-2
7.
Micromachines (Basel) ; 14(8)2023 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-37630121

RESUMEN

The needle valve, serving as the flow control unit of the thruster system, is a crucial component of the entire thruster. Its performance directly impacts the flow state of the rarefied gas in the micro-nozzle structure of the cold gas micro-thruster, thereby exerting a significant influence on the high precision and stability of the propulsion system as a whole. This study examines the impact of different needle valve structures on the flow and thrust in micro-nozzles using the DSMC method. The analysis includes discussions on the spatial distribution, Kn distribution, slip velocity distribution, and pressure distribution of the micro-nozzle's flow mechanism. Notably, increased curvature of the needle valve enhances the flow velocity in the throat and expansion section. The magnitude of the curvature directly affects the flow velocity, with larger curvatures resulting in higher velocities. Comparing different spool shapes, the conical spool shape minimizes the velocity gradient in the high-speed region at the junction between the spool area and the outlet pipe, particularly with a wide opening. Increasing the curvature of the spool leads to a higher velocity in the expansion section. Consequently, an arc-shaped spool valve maximizes the nitrogen flow at the nozzle during wide openings, thereby enhancing thrust. These research findings serve as a valuable reference for the structural design of the needle valve in the micro-nozzle of the cold gas micro-thruster.

8.
Anal Chim Acta ; 1265: 341282, 2023 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-37230579

RESUMEN

Food safety has emerged as a major global issue. Detecting foodborne pathogenic microorganisms and controlling them is vital to guard against foodborne diseases caused by microorganisms. However, the current detection methods need to meet the demand for real-time detection on the spot after a simple operation. Considering unresolved challenges, we developed an Intelligent Modular Fluorescent Photoelectric Microbe (IMFP) system containing a special detection reagent. This IMFP system can automatically monitor microbial growth in which the photoelectric detection, temperature control, fluorescent probe, and bioinformatics screen are integrated into one platform and employed to detect pathogenic microorganisms. Moreover, a specific culture medium was also developed, which matched the system platform for Coliform bacteria and Salmonella typhi. The developed IMFP system could attain a limit of detection (LOD) of about 1 CFU/mL for both bacteria, while the selectivity could reach 99%. In addition, the IMFP system was applied to detect 256 bacterial samples simultaneously. This platform reflects the high-throughput needs of fields for microbial identification and related requirements, such as the development of pathogenic microbial diagnostic reagents, antibacterial sterilization performance tests, and microbial growth kinetics. The IMFP system also confirmed the other merits, such as high sensitivity, high-throughput, and operation simplicity compared to conventional methods, and it has a high potential as a tool for application in the health and food security fields.


Asunto(s)
Contaminación de Alimentos , Inocuidad de los Alimentos , Contaminación de Alimentos/análisis , Límite de Detección , Medios de Cultivo , Bacterias , Colorantes Fluorescentes , Microbiología de Alimentos
9.
Int Immunopharmacol ; 116: 109825, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36764277

RESUMEN

Acute cardiovascular events increase significantly in postmenopausal women. The relationship between estrogen receptor (ER) and plaque stability in the postmenopausal stage remains to be elucidated. We aimed to explore whether ERα activation improves plaque instability in the postmenopausal stage. Here, we report that postmenopausal women showed increased macrophage activation and plaque instability with increased MCP-1, MMP9, TLR4, MYD88 and NF-κB p65 and decreased ERα and TIMP1 expression in the vascular endothelium. Moreover, ovariectomy in LDLR-/- mice resulted in a significant increase in plaque area and necrotic core area, as well as a significant decrease in collagen content and an increase in macrophage accumulation in the artery. Ovariectomy also reduced serum estrogen levels and ERα expression and upregulated TLR4 and MMP9 expression in arteries in LDLR-/- mice. Estrogen or phytoestrogen therapy upregulated the expression level of ERα in ovariectomized mice and increased plaque stability by inhibiting macrophage accumulation and TLR4 signaling. In vitro, LPS incubation of RAW264.7 cells resulted in a significant decrease in ERα and TIMP1 expression and an increase in TLR4 activation, and estrogen or phytoestrogen treatment increased ERα and TIMP1 expression and inhibited TLR4 activation and MMP9 expression in LPS-treated RAW264.7 cells. Compared to control siRNA transfected RAW264.7 cells, TLR4 siRNA promoted TIMP1 expression in RAW264.7 cells with LPS incubation, but did not affect ERα expression in RAW264.7 cells with or without LPS treatment. The ERα inhibitor MPP abolished the regulatory effect of estrogen or phytoestrogen on LPS-induced RAW264.7 cells. In conclusion, the present study demonstrates that decreased ERα expression promotes macrophage infiltration and plaque instability in the postmenopausal stage, and activation of ERα in the postmenopausal stage alleviates atherosclerotic plaque instability by inhibiting TLR4 signaling and macrophage-related inflammation.


Asunto(s)
Receptor alfa de Estrógeno , Placa Aterosclerótica , Receptor Toll-Like 4 , Animales , Femenino , Ratones , Receptor alfa de Estrógeno/genética , Receptor alfa de Estrógeno/metabolismo , Lipopolisacáridos , Macrófagos , Metaloproteinasa 9 de la Matriz/genética , Metaloproteinasa 9 de la Matriz/metabolismo , FN-kappa B/metabolismo , Fitoestrógenos , Posmenopausia , ARN Interferente Pequeño/metabolismo , Receptor Toll-Like 4/genética , Receptor Toll-Like 4/metabolismo , Humanos , Células RAW 264.7
10.
Micromachines (Basel) ; 15(1)2023 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-38258141

RESUMEN

When the satellite is in orbit, the thruster will experience drastic temperature changes (100-1000 K) under solar radiation, which will affect the rarefied gas flow state in the micro-nozzle structure of the cold gas micro-thruster. In this study, the effect of different wall temperatures on the rarefied flow and heat transfer in the micro-nozzle is investigated based on the DSMC method. The micro-nozzle structure in this paper has a micro-channel with a large length-to-diameter ratio of 10 and a micro-scale needle valve displacement (maximum needle valve displacement up to 4 µm). This leads to more pronounced multiscale flow characteristics in the micro-nozzle, which is more influenced by the change in wall temperature. At wall temperatures ranging from 100 K to 1000 K, the spatial distribution of local Kn distribution, slip velocity distribution, temperature, and wall heat flux distribution in the micro-nozzle were calculated. The slip flow region is located in the flow channel and transforms into transition flow as the slip velocity reaches approximately 50 m/s. The spatial distribution of the flow pattern is dominated by the wall temperature at small needle valve opening ratios. The higher the wall temperature, the smaller the temperature drop ratio in the low-temperature region inside the micro-nozzle. The results of the study provide a reference for the design of temperature control of micro-nozzles in cold gas micro-thrusters.

11.
J Med Chem ; 65(24): 16526-16540, 2022 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-36472561

RESUMEN

Blocking the entry of an HIV-1 targeting CCR5 coreceptor has emerged as an attractive strategy to develop HIV therapeutics. Maraviroc is the only CCR5 antagonist approved by FDA; however, serious side effects limited its clinical use. Herein, 21 novel tropane derivatives (6-26) were designed and synthesized based on the CCR5-maraviroc complex structure. Among them, compounds 25 and 26 had comparable activity to maraviroc and presented more potent inhibitory activity against a series of HIV-1 strains. In addition, compound 26 exhibited synergistic or additive antiviral effects in combination with other antiretroviral agents. Compared to maraviroc, both 25 and 26 displayed higher Cmax and AUC0-∞ and improved oral bioavailability in SD rats. In addition, compounds 25 and 26 showed no significant CYP450 inhibition and showed a novel binding mode with CCR5 different from that of maraviroc-CCR5. In summary, compounds 25 and 26 are promising drug candidates for the treatment of HIV-1 infection.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , VIH-1 , Ratas , Animales , Maraviroc/farmacología , Fármacos Anti-VIH/farmacología , Fármacos Anti-VIH/uso terapéutico , Antagonistas de los Receptores CCR5/farmacología , Ciclohexanos/farmacología , Triazoles/farmacología , Triazoles/uso terapéutico , Disponibilidad Biológica , Ratas Sprague-Dawley , Infecciones por VIH/tratamiento farmacológico , Tropanos/farmacología , Receptores CCR5/metabolismo
12.
Front Public Health ; 10: 970880, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36238254

RESUMEN

Objectives: This study aims to explore the interaction of different pathogens in Hand, foot and mouth disease (HFMD) by using a mathematical epidemiological model and the reported data in five regions of China. Methods: A cross-regional dataset of reported HFMD cases was built from four provinces (Fujian Province, Jiangsu province, Hunan Province, and Jilin Province) and one municipality (Chongqing Municipality) in China. The subtypes of the pathogens of HFMD, including Coxsackievirus A16 (CV-A16), enteroviruses A71 (EV-A71), and other enteroviruses (Others), were included in the data. A mathematical model was developed to fit the data. The effective reproduction number (R eff ) was calculated to quantify the transmissibility of the pathogens. Results: In total, 3,336,482 HFMD cases were collected in the five regions. In Fujian Province, the R eff between CV-A16 and EV-A71&CV-A16, and between CV-A16 and CV-A16&Others showed statistically significant differences (P < 0.05). In Jiangsu Province, there was a significant difference in R eff (P < 0.05) between the CV-A16 and Total. In Hunan Province, the R eff between CV-A16 and EV-A71&CV-A16, between CV-A16 and Total were significant (P < 0.05). In Chongqing Municipality, we found significant differences of the R eff (P < 0.05) between CV-A16 and CV-A16&Others, and between Others and CV-A16&Others. In Jilin Province, significant differences of the R eff (P < 0.05) were found between EV-A71 and Total, and between Others and Total. Conclusion: The major pathogens of HFMD have changed annually, and the incidence of HFMD caused by others and CV-A16 has surpassed that of EV-A71 in recent years. Cross-regional differences were observed in the interactions between the pathogens.


Asunto(s)
Infecciones por Enterovirus , Enterovirus , Enfermedad de Boca, Mano y Pie , China/epidemiología , Infecciones por Enterovirus/epidemiología , Enfermedad de Boca, Mano y Pie/epidemiología , Humanos , Incidencia
13.
Polymers (Basel) ; 14(15)2022 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-35956554

RESUMEN

Early diagnosis of metastatic colorectal cancer (mCRC) is extremely critical to improve treatment and extend survival. W3 is an aptamer that can specifically bind to mCRC cells with high affinity. Graphene oxide (GO) is a two-dimensional graphitic carbon nanomaterial, which has widely used in constructing biosensors. In this study, we have developed a no-wash fluorescent aptasensor for one-step and sensitive detection of mCRC LoVo cells. It is based on fluorescence resonance energy transfer (FRET) between GO and the W3 aptamer labeled with 5-carboxyfluorescein (FAM). GO can quench the green fluorescence of the FAM-labeled W3 (FAM-W3). In the presence of the target cells, FAM-W3 preferentially binds the target cells and detaches from the surface of GO, leading to the fluorescence of FAM recovery. It was demonstrated that the fluorescence recovery increases linearly in a wide range of 0~107 cells/mL (R2 = 0.99). The GO-based FAM-labeled W3 aptasensor (denoted as FAM-W3-GO) not only specifically recognizes mCRC cell lines (LoVo and HCT116), but also sensitively differentiates the target cells from mixed cells, even in the presence of only 5% of the target cells. Furthermore, FAM-W3-GO was applied to detect LoVo cells in human whole blood, which showed good reproducibility with an RSD range of 1.49% to 1.80%. Therefore, FAM-W3-GO may have great potential for early diagnosis of mCRC. This strategy of GO-based fluorescent aptasensor provides a simple, one-step, and highly sensitive approach for the detection of mCRC cells.

14.
Phytomedicine ; 101: 154120, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35523117

RESUMEN

BACKGROUND: Postmenopausal women have a high incidence of atherosclerosis. Phytosterols have been shown to have cholesterol-lowering properties. Alisa B 23-acetate (AB23A) is a biologically active plant sterol isolated from Chinese herbal medicine Alisma. However, the atherosclerosis effect of AB23A after menopause and its possible mechanism have not been reported yet. PURPOSE: To explore whether AB23A can prevent atherosclerosis by regulating farnesoid X receptor and subsequently increasing fecal bile acid and cholesterol excretion to reduce plasma cholesterol levels. METHODS: Aortic samples from premenopausal and postmenopausal women with ascending aortic arteriosclerosis were analyzed, and bilateral ovariectomized (OVX) female LDLR-/- mice and free fatty acid (FFA)-treated L02 cells were used to analyze the effect of AB23A supplementation therapy. RESULTS: AB23A increased fecal cholesterol and bile acids (BAs) excretion dependent on activation of hepatic farnesoid X receptor (FXR) in ovariectomized mice. AB23A inhibited hepatic cholesterol 7α-hydroxylase (CYP7A1) and sterol 12α-hydroxylase (CYP8B1) via inducing small heterodimer partner (SHP) expression. On the other hand, AB23A increased the level of hepatic chenodeoxycholic acid (CDCA), and activated the hepatic BSEP signaling. The activation of hepatic FXR-BSEP signaling by AB23A in ovariectomized mice was accompanied by the reduction of liver cholesterol, hepatic lipolysis, and bile acids efflux, and reduced the damage of atherosclerosis. In vitro, AB23A fixed abnormal lipid metabolism in L02 cells and increased the expression of FXR, BSEP and SHP. Moreover, the inhibition and silencing of FXR canceled the regulation of BSEP by AB23A in L02 cells. CONCLUSION: Our results shed light into the mechanisms behind the cholesterol-lowering of AB23A, and increasing FXR-BSEP signaling by AB23A may be a potential postmenopausal atherosclerosis therapy.


Asunto(s)
Aterosclerosis , Ácidos y Sales Biliares , Animales , Aterosclerosis/tratamiento farmacológico , Aterosclerosis/metabolismo , Aterosclerosis/prevención & control , Ácidos y Sales Biliares/metabolismo , Colestenonas , Colesterol/metabolismo , Colesterol 7-alfa-Hidroxilasa/metabolismo , Femenino , Humanos , Hígado , Ratones
15.
Micromachines (Basel) ; 13(4)2022 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-35457902

RESUMEN

During the working process of the ADN-based thruster, continuously, heat generated by the chemical reaction in the combustion chamber will transfer along the upstream capillary, the propellant in the capillary continuously absorbs heat under the effect of heat transfer from the wall and undergoes a phase change when the saturation temperature is reached. In this study, effects of the downstream heating temperature (623 K to 923 K) on mass flow rate and pressure change in the capillary were investigated based on the established test platform. Simultaneously, the VOF (volume of fraction) model, and the Lee phase transition model coupled with the Navier-Stokes method was utilized to simulate the spatial distribution of the gas-liquid propellant in the capillary. The results show that the ADN-based propellant firstly formed bubbles on the inner wall surface near the exit of the capillary, and these vapor bubbles moved and grew upstream along the capillary. Due to the cooling effect of the ADN-based propellant inflow, the temperature distribution of the front chamber and capillary gradually reached equilibrium. Bubbles were constantly generated in the capillary, and as the heat reflux intensified, the total volume of bubbles in the capillary continued increasing. Single-phase flow, annular flow, wave flow, and segment plug flow appeared sequentially along the axial direction of the capillary, and the proportion of gas phase volume fraction at the capillary outlet section gradually increased.

16.
J Med Chem ; 65(11): 7697-7716, 2022 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-35439002

RESUMEN

Targeting sphingosine kinase 1 (SphK1) has become a novel strategy for the treatment of inflammatory bowel disease and cancer via the SphK1/S1P signaling pathway. However, exploration of SphK1 inhibitor therapeutic applications has been hampered by the poor pharmacokinetic properties of these SphK1 inhibitors. Herein, we report the structural optimization and structure-activity relationship studies of a series of novel SphK1 inhibitors. The novel compound 28 selectively inhibits SphK1 and exhibits higher anti-proliferative activity compared to the positive compound PF-543 in various cancer cells, which is associated with the induction of G0/G1 phase arrest and apoptosis; besides, it could also inhibit the cell migration. Further, compound 28 can suppress in vivo growth of both colon tumor and triple-negative breast tumor and inhibits the lung metastasis of triple-negative breast cancer with higher potency compared with that of PF-543. Collectively, compound 28 represents a promising lead compound for the treatment of solid tumor and the metastasis.


Asunto(s)
Neoplasias Pulmonares , Neoplasias de la Mama Triple Negativas , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Lisofosfolípidos/metabolismo , Fosfotransferasas (Aceptor de Grupo Alcohol) , Esfingosina/metabolismo , Neoplasias de la Mama Triple Negativas/patología
17.
Zygote ; 30(3): 358-364, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34676817

RESUMEN

Methomyl is a broad-spectrum carbamate insecticide that has a variety of toxic effects on humans and animals. However, there have been no studies on the toxicity of methomyl in female mammalian oocytes. This study investigated the toxic effects of environmental oestrogen methomyl exposure on mouse oocyte maturation and its possible mechanisms. Our results indicated that methomyl exposure inhibited polar body extrusion in mouse oocytes. Compared with that in the control group, in the methomyl treatment group, superoxide anion free radicals in oocytes were significantly increased. In addition, the mitochondrial membrane potential of metaphase II stage oocytes in the methomyl treatment group was significantly decreased, resulting in reduced mouse oocyte quality. After 8.5 h of exposure to methomyl, metaphase I stage mouse oocytes displayed an abnormal spindle morphology. mRNA expression of the pro-apoptotic genes Bax and Caspase-3 in methomyl-treated oocytes increased, which confirmed the apoptosis. Collectively, our results indicated that mouse oocyte maturation is defective after methomyl treatment at least through disruption of spindle morphology, mitochondrial function and by induction of oxidative stress.


Asunto(s)
Metomil , Oocitos , Animales , Femenino , Mamíferos , Metafase , Metomil/metabolismo , Metomil/farmacología , Ratones , Mitocondrias , Oogénesis
18.
Glob Food Sec ; 28: 100463, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34513581

RESUMEN

The outbreak and wide spread of COVID-19 poses a new threat to global food security. This paper aims to address two important policy related issues, that is which agricultural subsector suffers more under zoonotic diseases and how do zoonotic diseases affect these subsectors. Using provincial panel data of 24 main farm commodities in China from 2002 to 2017, this paper identifies the impacts of zoonotic diseases and projects the potential disruption of COVID-19 to agricultural output in China under three scenarios. The main findings are as follows. First, zoonotic diseases have adverse impacts on almost all the farm commodities, while livestock on average suffers more than crops. Second, zoonotic diseases affect these subsectors mainly through the channel of adverse shocks on total factor productivity (TFP). Third, while a few subsectors can find a way to offset part of the TFP loss by applying more input, most subsectors suffer from both input reduction and TFP loss. Fourth, the spread of COVID-19 is projected to lower the growth rates of China's crop and livestock sector by 1.1%-2.3% and 1.3%-2.6%, with TFP loss by 1.1%-2.0% and 1.4%-2.7%, respectively, in 2020. This paper then discusses several policy implications for mitigating the negative impacts of COVID-19 on agricultural production in China and elsewhere.

19.
J Product Anal ; 55(2): 135-153, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33814698

RESUMEN

The goal of this article is to answer two questions: Has world agricultural convergence occurred? If not, how can this goal be fulfilled? This article introduces a model averaging method to consider both a parametric and a semi-parametric SFA model to better estimate technical efficiency. Then, three types of convergence tests are employed to check if world agricultural catch-up occurs and to determine the degree of convergence across different groups of countries. The empirical results on a balanced panel of 126 countries from 1970-2014 show that world agricultural convergence has not occurred. This article then investigates the situations in different groups of countries and discusses how to use international trade, irrigation system, and structural transformation to improve agricultural efficiency and to diminish the efficiency gap among different countries in the future.

20.
Front Psychol ; 12: 585837, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33613378

RESUMEN

Based on early experiences and current conditions, a future time perspective influences college students' behaviors, while psychological violence critically threatens college students' health. This study explored the relationship between a future time perspective and the psychological violence of perpetrators based on an online investigation of 1424 college students (87.1% women) aged 17 to 31 in China. The results showed that a future time perspective is significantly positively associated with psychological violence. Positive future orientation is negatively associated with psychological violence. Negative and confused future orientations are positively associated with psychological violence. These findings support the need to introduce an intervention regarding a future time perspective to reduce psychological violence among college students.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...