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1.
Environ Sci Technol ; 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38810222

RESUMO

The redox chemistry of mercury (Hg) in the atmosphere exerts a significant influence on its global cycle. However, our understanding of this important process remains shrouded in uncertainty. In this study, we utilize three-dimensional atmospheric Hg isotope modeling to evaluate the isotopic composition of particle-bound mercury [HgII(P)] in the global atmosphere. We investigate various chemistry mechanisms and find that they induce remarkably disparate odd-number mass-independent fractionation (odd-MIF) in HgII(P) on a global scale. The observed odd-MIF data identify the essential role of sea salt aerosol debromination in the redox chemistry of atmospheric Hg and underscore the predominant influence of Br oxidation in the marine boundary layer. The odd-MIF signatures significantly narrow the uncertainty range of redox chemistry rates and constrain the photoreduction of HgII(P) at a magnitude of 10-3 JNO2 (local photolysis frequency of NO2) in the global atmosphere. This study advances our understanding of atmospheric Hg chemistry processes and provides insights into the potential impacts of climate change on Hg cycling.

2.
Environ Sci Technol ; 57(39): 14589-14601, 2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37585923

RESUMO

Sea ice (including overlying snow) is a dynamic interface between the atmosphere and the ocean, influencing the mercury (Hg) cycling in polar oceans. However, a large-scale and process-based model for the Hg cycle in the sea ice environment is lacking, hampering our understanding of regional Hg budget and critical processes. Here, we develop a comprehensive model for the Hg cycle at the ocean-sea ice-atmosphere interface with constraints from observational polar cryospheric data. We find that seasonal patterns of average total Hg (THg) in snow are governed by snow thermodynamics and deposition, peaking in springtime (Arctic: 5.9 ng/L; Antarctic: 5.3 ng/L) and minimizing during ice formation (Arctic: 1.0 ng/L, Antarctic: 0.5 ng/L). Arctic and Antarctic sea ice exhibited THg concentration peaks in summer (0.25 ng/L) and spring (0.28 ng/L), respectively, governed by different snow Hg transmission pathways. Antarctic snow-ice formation facilitates Hg transfer to sea ice during spring, while in the Arctic, snow Hg is primarily moved through snowmelt. Overall, first-year sea ice acts as a buffer, receiving atmospheric Hg during ice growth and releasing it to the ocean in summer, influencing polar atmospheric and seawater Hg concentrations. Our model can assess climate change effects on polar Hg cycles and evaluate the Minamata Convention's effectiveness for Arctic populations.

3.
Anal Bioanal Chem ; 415(3): 439-445, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36370203

RESUMO

Estrogens are involved in many physiological processes in vivo. The accurate and rapid quantification of estrogens is required for the diagnosis and prognosis of estrogen-related diseases. To achieve high-volume assays, we developed and validated a sample-multiplexing liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the quantification of serum estrogens including estrone (E1), estradiol (E2), and estriol (E3). A total of 100 µL serum samples were extracted using ethyl acetate. After derivatization with either dansyl chloride or pyridine-3-sulfonyl chloride, derivatized samples were combined. Then we performed the second liquid-liquid extraction using hexane to purify the mixture. Finally, the reconstitution solutions were injected into LC-MS/MS. In addition, the proposed LC-MS/MS method was validated according to FDA and CLSI guidelines. Within a single run (7 min), this sample-multiplexing LC-MS/MS method could simultaneously analyze E1, E2, and E3 in 2 serum samples. Meanwhile, the method demonstrated satisfactory analytical characteristics including accuracy (87.7-110.3%), linearity (2-1000 pg/mL, R2 > 0.99), precision (intra-assay CV, 1.7-8.7%; inter-assay CV, 1.9-9.4%), and negligible interference and carry-over effect as well as acceptable matrix effect. In conclusion, this sample-multiplexing LC-MS/MS method has achieved a doubled-throughput assay for simultaneous quantification of E1, E2, and E3 without compromising analytical characteristics.


Assuntos
Estrogênios , Espectrometria de Massas em Tandem , Estrogênios/análise , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Estrona , Estradiol
4.
Macromol Rapid Commun ; 43(17): e2200188, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35436806

RESUMO

Photonic balls can be facilely obtained through interfacial self-assembly of amphiphilic bottlebrush block polymers (BBCPs) within a water-in-oil-in-water (w/o/w) multiple emulsion system, and polystyrene (PS) has been employed as the skeleton of the balls showing no responsive properties. Here, the design and synthesis of core-shell BBCPs are demonstrated with a poly(tert-butyl acrylate)-block-polystyrene (PtBA-b-PS) block copolymer as the hydrophobic side chains and poly(ethylene glycol) as the hydrophilic block. Interfacial self-assembly of the core-shell BBCPs within shrinking droplets produces porous microspheres with full-spectrum structural colors through an organized spontaneous emulsification process. The PtBA core wrapped by PS in the skeleton of the balls can be converted into polyacrylic acid (PAA) forming an ionic channel responsive to pH variations. Consequently, the hydrolyzed photonic balls show different colors under different pH conditions dependent on varying degrees of ionization and hydration of the PAA channel. Reflected colors can be verified using an optical spectrometer, providing an effective strategy for precise pH indication.


Assuntos
Polímeros , Poliestirenos , Canais Iônicos , Polietilenoglicóis/química , Polímeros/química , Poliestirenos/química , Água
5.
Sensors (Basel) ; 22(15)2022 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-35898060

RESUMO

This paper presents a lateral and longitudinal coupling controller for a trajectory-tracking control system. The proposed controller can simultaneously minimize lateral tracking deviation while tracking the desired trajectory and vehicle speed. Firstly, we propose a hierarchical control structure composed of upper and lower-level controllers. In the upper-level controller, the linear quadratic regulator (LQR) controller is designed to compute the desired front wheel steering angle for minimizing the lateral tracking deviation, and the model-predictive controller is developed to compute the desired acceleration for maintaining the planed vehicle speed. The lower-level controller enables the achievement of the desired steering angle and acceleration via the corresponding component devices. Furthermore, an observer based on the Extended Kalman Filter (EKF) is proposed to update the vehicle driving states, which are sensitive to the trajectory-tracking control and difficult to measure directly using the existing vehicle sensors. Finally, the Co-simulation (CarSim-MATLAB/Simulink) results demonstrate that the proposed coupling controller is able to robustly realize the trajectory tracking control and can effectively reduce the lateral tracking error.

6.
Hum Brain Mapp ; 42(7): 2236-2249, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33570215

RESUMO

Resting-state functional connectivity in the human brain is heritable, and previous studies have investigated the genetic basis underlying functional connectivity. However, at present, the molecular mechanisms associated with functional network centrality are still largely unknown. In this study, functional networks were constructed, and the graph-theory method was employed to calculate network centrality in 100 healthy young adults from the Human Connectome Project. Specifically, functional connectivity strength (FCS), also known as the "degree centrality" of weighted networks, is calculated to measure functional network centrality. A multivariate technique of partial least squares regression (PLSR) was then conducted to identify genes whose spatial expression profiles best predicted the FCS distribution. We found that FCS spatial distribution was significantly positively correlated with the expression of genes defined by the first PLSR component. The FCS-related genes we identified were significantly enriched for ion channels, axon guidance, and synaptic transmission. Moreover, FCS-related genes were preferentially expressed in cortical neurons and young adulthood and were enriched in numerous neurodegenerative and neuropsychiatric disorders. Furthermore, a series of validation and robustness analyses demonstrated the reliability of the results. Overall, our results suggest that the spatial distribution of FCS is modulated by the expression of a set of genes associated with ion channels, axon guidance, and synaptic transmission.


Assuntos
Córtex Cerebral/fisiologia , Conectoma , Expressão Gênica/fisiologia , Rede Nervosa/fisiologia , Adulto , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/metabolismo , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/metabolismo , Adulto Jovem
7.
J Lipid Res ; 61(4): 580-586, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31964762

RESUMO

Analyzing global steroid metabolism in humans can shed light on the etiologies of steroid-related diseases. However, existing methods require large amounts of serum and lack the evaluation of accuracy. Here, we developed an LC/MS/MS method for the simultaneous quantification of 12 steroid hormones: testosterone, pregnenolone, progesterone, androstenedione, corticosterone, 11-deoxycortisol, cortisol, 17-hydroxypregnenolone, 17-hydroxyprogesterone, dehydroepiandrosterone, estriol, and estradiol. Steroids and spiked internal standards in 100 µl serum were extracted by protein precipitation and liquid-liquid extraction. The organic phase was dried by evaporation, and isonicotinoyl chloride was added for steroid derivatization, followed by evaporation under nitrogen and redissolution in 50% methanol. Chromatographic separation was performed on a reverse-phase PFP column, and analytes were detected on a triple quadrupole mass spectrometer with ESI. The lower limits of quantification ranged from 0.005 ng/ml for estradiol to 1 ng/ml for cortisol. Apparent recoveries of steroids at high, medium, and low concentrations in quality control samples were between 86.4% and 115.0%. There were limited biases (-10.7% to 10.5%) between the measured values and the authentic values, indicating that the method has excellent reliability. An analysis of the steroid metabolome in pregnant women highlighted the applicability of the method in clinical serum samples. We conclude that the LC/MS/MS method reported here enables steroid metabolome analysis with high accuracy and reduced serum consumption, indicating that it may be a useful tool in both clinical and scientific laboratory research.


Assuntos
Análise Química do Sangue/métodos , Cromatografia Líquida , Limite de Detecção , Metabolômica/métodos , Esteroides/sangue , Esteroides/metabolismo , Espectrometria de Massas em Tandem/métodos , Métodos Analíticos de Preparação de Amostras , Feminino , Humanos , Gravidez , Solventes/química , Esteroides/isolamento & purificação
8.
J Magn Reson Imaging ; 52(1): 174-182, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31922353

RESUMO

BACKGROUND: Despite several treatment options that are available for meningiomas, surgery is the only method currently practiced. Peritumoral brain edema (PTBE) in meningiomas causes difficulty marginalizing the dissection in an intraoperative setting. PURPOSE: To evaluate whether the epidemiological variables, imaging characteristics, and pathologic parameters are correlated with the presence of PTBE in meningiomas. STUDY TYPE: Retrospective study from 2015 to 2018. SUBJECTS: In all, 550 patients with histopathologically confirmed meningioma were included. After exclusion of patients with extradural, spinal, and intraventricular meningiomas and those with image artifacts, a total of 441 patients were included in the final analysis. FIELD STRENGTH/SEQUENCE: Images were performed with 3T MR scanners and axial/sagittal T1 WI, axial/coronal T2 WI and axial/sagittal/coronal contrast-enhanced T1 WI after administration of 0.1 mmol/kg of body weight of Gd-DTPA. ASSESSMENT: Fourteen variables were patients' age, sex, skull changes, calcification, density, location, margin, volume, cerebrospinal fluid (CSF) cleft, signal intensity (SI) on T2 WI, degree and pattern of contrast enhancement, WHO histological classification, and Ki-67 labeling index. STATISTICAL TESTS: The relationship between each factor and the formation of PTBE was examined by multivariate logistic regression analysis. RESULTS: After multivariate logistic regression, the absence of CSF cleft (odds ratio [OR]: 63.43, 95% confidence interval [CI]: 27.24-121.42, P = 1.2 × 10-8 ), non-skull base location (OR: 15.32, 95% CI: 5.81-28.23, P = 0.0008), high SI on T2 WI (OR: 5.05, 95% CI: 2.27-14.88, P = 0.01), and G I uncommon subtypes (OR: 4.75, 95% CI: 1.42-15.94, P = 0.01) were found to be significant independent factors associated with the occurrence of PTBE in meningiomas. In patients with PTBE-positive meningiomas, there was no significant correlation between the volume of PTBE and the volume of the tumor (r = 0.17, P = 0.60). DATA CONCLUSION: These factors may be suggestive of anticipating the formation of PTBE. LEVEL OF EVIDENCE: 3 Technical Efficacy Stage: 3 J. Magn. Reson. Imaging 2020;52:174-182.


Assuntos
Edema Encefálico , Neoplasias Meníngeas , Meningioma , Edema Encefálico/diagnóstico por imagem , Edema Encefálico/epidemiologia , Fatores Epidemiológicos , Humanos , Imageamento por Ressonância Magnética , Neoplasias Meníngeas/complicações , Neoplasias Meníngeas/diagnóstico por imagem , Meningioma/complicações , Meningioma/diagnóstico por imagem , Estudos Retrospectivos
9.
Mikrochim Acta ; 187(3): 165, 2020 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-32052188

RESUMO

For the first time, boronate affinity chromatography and metal oxide affinity chromatography mechanisms for cis-diol-compounds extraction are simultaneously realized on a single material, termed borated zirconia. This material was prepared by hydrolyzing zirconium butoxide with boric acid under non-aqueous environment. The diameter of formed particles is around 200 nm. By extracting catechol under different pH conditions or with phosphate ion competition, the dual affinity mechanisms of borated zirconia are confirmed. Benefiting from such unique feature, borated zirconia can function well under neutral condition. By using borated zirconia for dispersive solid phase extraction, specific capture of cis-diol-containing catecholamines, including epinephrine (E), norepinephrine (NE) and dopamine (DA), was achieved. A reliable LC-MS/MS method was established and validated for quantification of these target analytes in plasma samples after derivatisation with benzoyl chloride. The linear ranges are 0.010-0.200 ng·mL-1 for E and DA, and 0.050-1.000 ng·mL-1 for NE. The limits of quantification are 0.008, 0.020 and 0.004 ng·mL-1 for E, NE and DA respectively. By analyzing samples from healthy volunteers and schizophrenia patients, the plasma concentrations of E, NE and DA were found to be higher for the latter. Graphical AbstractSchematic representation of boronate combined metal oxide affinity chromatography (BMOAC) extraction of cis-diol catecholamines from human plasma by borated zirconia following with benzoyl chloride derivatization and LC-MS determination.


Assuntos
Catecolaminas/sangue , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Zircônio/química , Humanos
10.
New Phytol ; 222(3): 1338-1351, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30664250

RESUMO

Evolutionary history shapes the interspecific relatedness and intraspecific variation, which has a profound influence on plant functional traits and productivity. However, it is far from clear how the phylogenetic relatedness among species and intraspecific variation could contribute to the observed variance in plant biomass responses to climate warming. We compiled a dataset with 284 species from warming experiments to explore the relative importance of phylogenetic, intraspecific, experimental and ecological factors to warming effects on plant biomass, using phylogenetic eigenvector regression and variance decomposition. Our results showed that phylogenetic relatedness could account for about half the total variance in biomass responses to warming, which were correlated with leaf economic traits at the family level but not at species level. The intraspecific variation contributed to approximately one-third of the variance, whereas the experimental design and ecological characteristics only explained 7-17%. These results suggest that intrinsic factors (evolutionary history) play more important roles than extrinsic factors (experimental treatment and environment) in determining the responses of plant biomass to warming at the global scale. This highlights the urgent need for land surface models to include evolutionary aspects in predicting ecosystem functions under climate change.


Assuntos
Evolução Biológica , Biomassa , Aquecimento Global , Plantas/anatomia & histologia , Filogenia , Folhas de Planta/fisiologia , Característica Quantitativa Herdável , Especificidade da Espécie
12.
Magn Reson Imaging ; 108: 86-97, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38331053

RESUMO

To introduce a new cross-domain complex convolution neural network for accurate MR image reconstruction from undersampled k-space data. Most reconstruction methods utilize neural networks or cascade neural networks in either the image domain and/or the k-space domain. However, these methods encounter several challenges: 1) Applying neural networks directly in the k-space domain is suboptimal for feature extraction; 2) Classic image-domain networks have difficulty in fully extracting texture features; and 3) Existing cross-domain methods still face challenges in extracting and fusing features from both image and k-space domains simultaneously. In this work, we propose a novel deep-learning-based 2-D single-coil complex-valued MR reconstruction network termed TEID-Net. TEID-Net integrates three modules: 1) TE-Net, an image-domain-based sub-network designed to enhance contrast in input features by incorporating a Texture Enhancement Module; 2) ID-Net, an intermediate-domain sub-network tailored to operate in the image-Fourier space, with the specific goal of reducing aliasing artifacts realized by leveraging the superior incoherence property of the decoupled one-dimensional signals; and 3) TEID-Net, a cross-domain reconstruction network in which ID-Nets and TE-Nets are combined and cascaded to boost the quality of image reconstruction further. Extensive experiments have been conducted on the fastMRI and Calgary-Campinas datasets. Results demonstrate the effectiveness of the proposed TEID-Net in mitigating undersampling-induced artifacts and producing high-quality image reconstructions, outperforming several state-of-the-art methods while utilizing fewer network parameters. The cross-domain TEID-Net excels in restoring tissue structures and intricate texture details. The results illustrate that TEID-Net is particularly well-suited for regular Cartesian undersampling scenarios.


Assuntos
Algoritmos , Processamento de Imagem Assistida por Computador , Processamento de Imagem Assistida por Computador/métodos , Redes Neurais de Computação , Imageamento por Ressonância Magnética/métodos , Artefatos
13.
Nat Commun ; 15(1): 4490, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38802424

RESUMO

Mercury (Hg), a potent neurotoxin posing risks to human health, is cycled through vegetation uptake, which is susceptible to climate change impacts. However, the extent and pattern of these impacts are largely unknown, obstructing predictions of Hg's fate in terrestrial ecosystems. Here, we evaluate the effects of climate change on vegetation elemental Hg [Hg(0)] uptake using a state-of-the-art global terrestrial Hg model (CLM5-Hg) that incorporates plant physiology. In a business-as-usual scenario, the terrestrial Hg(0) sink is predicted to decrease by 1870 Mg yr-1 in 2100, that is ~60% lower than the present-day condition. We find a potential decoupling between the trends of CO2 assimilation and Hg(0) uptake process by vegetation in the 21st century, caused by the decreased stomatal conductance with increasing CO2. This implies a substantial influx of Hg into aquatic ecosystems, posing an elevated threat that warrants consideration during the evaluation of the effectiveness of the Minamata Convention.


Assuntos
Dióxido de Carbono , Mudança Climática , Ecossistema , Mercúrio , Plantas , Dióxido de Carbono/metabolismo , Mercúrio/metabolismo , Plantas/metabolismo
14.
Front Pharmacol ; 14: 1266890, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38074150

RESUMO

Purpose: On 12 April 2019, erdafitinib gained the first FDA approval as the second-line treatment for adult patients with locally advanced or metastatic urothelial cancer following progression during or after at least one previous line of platinum-based chemotherapy. However, the long-term safety profile of erdafitinib in a large patient population remains unexplored. The current study aimed to assess the adverse events (AEs) associated with erdafitinib through data mining of the US Food and Drug Administration Adverse Event Reporting System (FAERS). Method: The reporting odds ratio (ROR), the proportional reporting ratio (PRR), the Bayesian confidence propagation neural network (BCPNN), and the multi-item gamma Poisson shrinker (MGPS) algorithms based on disproportionality were employed to quantify the signals of erdafitinib-associated AEs. Results: A total of 6,322,279 reports of AEs were retrieved from the FAERS database spanning 2019 to 2022, out of which, 700 reports of erdafitinib as the "primary suspected" were identified. These erdafitinib-induced AEs were observed across 24 targeted system organ classes (SOCs). After conforming to the four algorithms at the same time, a total of 441 signals of erdafitinib-induced AEs were detected across 23 SOCs. Notably, signals associated with metabolism and nutrition disorders, eye disorders, and skin and subcutaneous tissue disorders were among the most prevalent. The median onset time for AEs was found to be 54 days [interquartile range (IQR) 17-112 days], with a majority of AEs occurring within the initial 6 months after initiating erdafitinib (37.23% within the first month, 15.53% within the second month, and 16.79% within the third month). Conclusion: The findings of this study align with existing clinical observations, offering a comprehensive long-term post-marketing safety evaluation of erdafitinib. The results provide valuable evidence to enhance the understanding of erdafitinib's safety profile, aiding further research and guiding clinical practice.

15.
Environ Int ; 174: 107904, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37012193

RESUMO

The vegetation uptake of atmospheric elemental mercury [Hg(0)] and its subsequent littering are critical processes of the terrestrial Hg cycles. There is a large uncertainty in the estimated global fluxes of these processes due to the knowledge gap in the underlying mechanisms and their relationship with environmental factors. Here, we develop a new global model based on the Community Land Model Version 5 (CLM5-Hg) as an independent component of the Community Earth System Model 2 (CESM2). We explore the global pattern of gaseous elemental Hg [Hg(0)] uptake by vegetation and the spatial distribution of litter Hg concentration constrained by observed datasets as well as its driving mechanism. The annual vegetation uptake of Hg(0) is estimated as 3132 Mg yr-1, which is considerably higher than previous global models. The scheme of dynamic plant growth including stomatal activities substantially improves the estimation for global terrestrial distribution of Hg, compared to the leaf area index (LAI) based scheme that is often used by previous models. We find the global distribution of litter Hg concentrations driven by vegetation uptake of atmospheric Hg(0), which are simulated to be higher in East Asia (87 ng/g) than in the Amazon region (63 ng/g). Meanwhile, as a significant source for litter Hg, the formation of structural litter (cellulose litter + lignin litter) results in a lagging effect between Hg(0) deposition and litter Hg concentration, implying the buffering effect of vegetation on the air-land exchange of Hg. This work highlights the importance of vegetation physiology and environmental factors in understanding the vegetation sequestration of atmospheric Hg globally, and calls for greater efforts to protect forests and afforestation.


Assuntos
Poluentes Atmosféricos , Mercúrio , Mercúrio/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Florestas , Folhas de Planta
16.
Ecology ; 104(2): e3877, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36178039

RESUMO

Subtropical evergreen broadleaf forests (SEBF) are experiencing and expected to suffer more frequent and severe drought events. However, how the hydraulic traits directly link to the mortality and recovery of SEBF trees remains unclear. In this study, we conducted a drought-rewatering experiment on tree seedlings of five dominant species to investigate how the hydraulic traits were related to tree mortality and the resistance and recovery of photosynthesis (A) and transpiration (E) under different drought severities. Species with greater embolism resistance (P50 ) survived longer than those with a weaker P50 . However, there was no general hydraulic threshold associated with tree mortality, with the lethal hydraulic failure varying from 64% to 93% loss of conductance. The photosynthesis and transpiration of tree species with a greater P50 were more resistant to and recovered faster from drought than those with lower P50 . Other plant traits could not explain the interspecific variation in tree mortality and drought resistance and recovery. These results highlight the unique importance of embolism resistance in driving carbon and water processes under persistent drought across different trees in SEBFs. The absence of multiple efficient drought strategies in SEBF seedlings implies the difficulty of natural seedling regeneration under future droughts, which often occurs after destructive disturbances (e.g., extreme drought events and typhoon), suggesting that this biome may be highly vulnerable to co-occurring climate extremes.


Assuntos
Embolia , Árvores , Secas , Florestas , Ecossistema , Água , Plântula , Folhas de Planta
17.
Sci Adv ; 9(43): eadj3133, 2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37889978

RESUMO

Perching-and-takeoff robot can effectively economize onboard power and achieve long endurance. However, dynamic perching on moving targets for a perching-and-takeoff robot is still challenging due to less autonomy to dynamically land, tremendous impact during landing, and weak contact adaptability to perching surfaces. Here, a self-sensing, impact-resistant, and contact-adaptable perching-and-takeoff robot based on all-in-one electrically active smart adhesives is proposed to reversibly perch on moving/static dry/wet surfaces and economize onboard energy. Thereinto, attachment structures with discrete pillars have contact adaptability on different dry/wet surfaces, stable adhesion, and anti-rebound; sandwich-like artificial muscles lower weight, enhance damping, simplify control, and achieve fast adhesion switching (on-off ratio approaching ∞ in several seconds); and the flexible pressure (0.204% per kilopascal)-and-deformation (force resolution, <2.5 millinewton) sensor enables the robot's autonomy. Thus, the perching-and-takeoff robot equipped with electrically active smart adhesives exhibits tremendous advantages of soft materials over their rigid counterparts and promising application prospect of dynamic perching on moving targets.

18.
Cell Host Microbe ; 30(3): 329-339.e5, 2022 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-35108497

RESUMO

Testosterone deficiency can lead to depressive symptoms in humans; however, the causes of this deficiency are incompletely understood. Here, we isolated Mycobacterium neoaurum from the fecal samples of testosterone-deficient patients with depression and showed that this strain could degrade testosterone in vitro. Furthermore, gavaging rats with M. neoaurum reduced their serum and brain testosterone levels and induced depression-like behaviors. We identified the gene encoding 3ß-hydroxysteroid dehydrogenase (3ß-HSD) as the enzyme causing testosterone degradation. Introducing 3ß-HSD into Escherichia coli enhanced its ability to degrade testosterone. Gavaging rats with 3ß-HSD-producing E. coli reduced their serum and brain testosterone levels and caused depression-like behaviors. Finally, compared with 16.67% of participants without depression, 42.99% (46/107) of the fecal samples of patients with depression harbored 3ß-HSD, and 60.87% (28/46) of these fecal samples expressed 3ß-HSD. These results suggest that 3ß-HSD expressed by gut microbes may be associated with depressive symptoms due to testosterone degradation.


Assuntos
Microbioma Gastrointestinal , Testosterona , 3-Hidroxiesteroide Desidrogenases/genética , 3-Hidroxiesteroide Desidrogenases/metabolismo , Animais , Depressão , Escherichia coli/genética , Escherichia coli/metabolismo , Humanos , Masculino , Ratos , Testosterona/metabolismo
19.
J Steroid Biochem Mol Biol ; 214: 105999, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34547380

RESUMO

Previous studies have demonstrated that steroids were associated with gestational diabetes mellitus (GDM). However, results from different studies remained inconsistent, and only a limited range of steroids were investigated in these studies. Therefore, we aimed to analyze comprehensive steroid profiling in Chinese women with GDM during third-trimester pregnancy. In 97 Chinese pregnant women, we measured steroid profile using a LC-MS/MS method, and calculated product-to-precursor ratios in metabolic pathways of steroids. Then sixteen genetic variants of genes encoding steroidogenic enzymes were genotyped by MassARRAY system. There were significant differences (P < 0.05) and obvious changes (fold change <0.67 or>1.5) in steroids (testosterone, estriol, pregnenolone and dehydroepiandrosterone) and product-to-precursor ratios (E2/T and T/AD) between GDM and control groups. After adjusting for maternal age, the TT genotype and T allele of CYP19A1 rs10046 were associated with an increased risk of GDM. And the CC genotype and C allele of HSD17B3 rs2257157 were also associated with an increased risk of GDM. Besides, pregnant women carrying TT genotype of CYP19A1 rs10046 and CC genotype of HSD17B3 rs2257157 had a lower E2/T ratio and higher T/AD ratio respectively comparing with those carrying other genotypes. In conclusion, our study suggested that testosterone, estriol, pregnenolone and dehydroepiandrosterone might be differential metabolites for gestational diabetes mellitus. The genetic variants rs10046 of CYP19A1 and rs2257157 of HSD17B3 could predispose to GDM in Chinese women.


Assuntos
Diabetes Gestacional/metabolismo , Esteroides/metabolismo , 17-Hidroxiesteroide Desidrogenases/genética , Adulto , Alelos , Aromatase/genética , China , Desidroepiandrosterona/metabolismo , Estriol/metabolismo , Feminino , Predisposição Genética para Doença , Variação Genética , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único , Gravidez , Pregnenolona/metabolismo , Risco , Testosterona/metabolismo
20.
Zhongguo Fei Ai Za Zhi ; 24(1): 13-18, 2021 Jan 20.
Artigo em Zh | MEDLINE | ID: mdl-33478185

RESUMO

BACKGROUND: Acute cerebral infarction is a form of Trousseau syndrome (TS), but is relatively rare and often overlooked by clinicians. The aim of this study was to investigate the clinical, laboratory and imaging features of acute cerebral infarction in non-small cell lung cancer (NSCLC) patients with TS. METHODS: Clinical data, laboratory examination and imaging data of 25 NSCLC patients with TS presented with acute cerebral infarction were collected retrospectively for analysis. RESULTS: Of the 25 patients, 18 males and 7 females, aged 39-78 years old, including 22 cases of adenocarcinoma, 2 cases of squamous cell carcinoma, and 1 case of large cell carcinoma; all patients had clinical symptoms and signs of acute cerebral infarction; plasma D-dimer was significantly increased, and prothrombin time and activated partial thromboplastin time were shortened to varying degrees; all patients showed acute multiple cerebral infarction foci involving multiple intracranial arterial blood supply areas on plain head magnetic resonance imaging (MRI) [diffusion-weighted imaging (DWI) sequence], the blood supply vessel lumen corresponding to the infarction foci did not show moderate to severe stenosis on the head MR angiography (MRA). CONCLUSIONS: NSCLC with multiple acute cerebral infarctions is a rare manifestation of TS, which is characterized by multiple acute cerebral infarctions involving multiple arterial blood supply areas with significant hypercoagulability. Improving the early understanding of this disease can provide some help for clinical diagnosis and treatment.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/complicações , Infarto Cerebral/diagnóstico por imagem , Neoplasias Pulmonares/complicações , Adulto , Idoso , Infarto Cerebral/etiologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
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