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1.
Nano Lett ; 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38747518

RESUMEN

Splash, one of the most visually apparent droplet dynamics, can manifest on any surface above a certain impact velocity, regardless of surface wettability. Previous studies demonstrate that elevating the substrate temperature can suppress droplet splash, which is unfavorable for many practical applications, such as spray cooling and combustion. Here, we report that the suppression effect of substrate temperature on splash is nullified by utilizing surfaces with nanostructures. By manipulating air evacuation time through surface nanostructures, we have identified a pathway for precise control over the splash threshold and the ability to tailor the dependence of the splash onset on surface temperature. We further propose a theoretical criterion to determine different splash regimes by considering the competition between air evacuation and the development of flow instabilities. Our findings underscore the crucial role of nanostructures in splash dynamics, offering valuable insights for the control of splash in various industrial scenarios.

2.
Small ; : e2311630, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38470212

RESUMEN

The floating gate devices, as a kind of nonvolatile memory, obtain great application potential in logic-in-memory chips. The 2D materials have been greatly studied due to atomically flat surfaces, higher carrier mobility, and excellent photoelectrical response. The 2D ReS2 flake is an excellent candidate for channel materials due to thickness-independent direct bandgap and outstanding optoelectronic response. In this paper, the floating gate devices are prepared with the ReS2 /h-BN/Gr heterojunction. It obtains superior nonvolatile electrical memory characteristics, including a higher memory window ratio (81.82%), tiny writing/erasing voltage (±8 V/2 ms), long retention (>1000 s), and stable endurance (>1000 times) as well as multiple memory states. Meanwhile, electrical writing and optical erasing are achieved by applying electrical and optical pulses, and multilevel storage can easily be achieved by regulating light pulse parameters. Finally, due to the ideal long-time potentiation/depression synaptic weights regulated by light pulses and electrical pulses, the convolutional neural network (CNN) constructed by ReS2 /h-BN/Gr floating gate devices can achieve image recognition with an accuracy of up to 98.15% for MNIST dataset and 91.24% for Fashion-MNIST dataset. The research work adds a powerful option for 2D materials floating gate devices to apply to logic-in-memory chips and neuromorphic computing.

3.
Rapid Commun Mass Spectrom ; 38(6): e9707, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38356093

RESUMEN

RATIONALE: A novel laser ablation-isotope ratio mass spectrometry (LA-IRMS) method for in situ analysis of sulfur isotopes in sulfides has been developed. Instead of the in situ reaction applied by the traditional laser microprobe, the analyte gas preparation in this method is separated temporally and spatially from the LA, resulting in improved precision and accuracy. METHODS: Our LA-IRMS system combines an ultraviolet LA system, an elemental analyzer (EA), a custom-built cryogenic concentration system, a continuous-flow interface, and an IRMS. The sulfide aerosol particles generated from LA were transferred by a helium carrier gas from the ablation cell into the reaction tube and were then converted into SO2 . Subsequently, SO2 was enriched in two cold traps and was finally introduced into the ion source of the IRMS through the continuous-flow interface. RESULTS: We measured three synthetic and four natural sulfide reference materials to test the performance of this method. Precisions of ±0.25‰-±0.48‰ and ±0.32‰-±0.64‰ (1SD, n = 5) for δ34 S values of synthetic and natural sulfide standards can be obtained for spot sizes ranging from 64 to 80 µm. Measured values and their recommended values showed a good linear relationship (R2 within 0.998 and 0.9995) with the slope of approaching unity (within 1.0509 and 1.1313). CONCLUSIONS: Data from the measurement of reference materials showed that the precision and accuracy of our method were satisfactory. This method is a powerful tool for in situ sulfur isotope measurement of sulfides and can be further applied to in situ carbon and oxygen isotope analyses.

4.
Small ; 19(52): e2304218, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37649201

RESUMEN

Superhydrophobic and slippery lubricant-infused surfaces have garnered significant attention for their potential to passively transport low-viscosity liquids like water (1 mPa s). Despite exciting progress, these designs have proven ineffective for transporting high-viscosity liquids such as polydimethylsiloxane (5500 mPa s) due to their inherent limitations imposed by the homogenous surface design, resulting in high viscous drags and compromised capillary forces. Here, a heterogenous water-infused divergent surface (WIDS) is proposed that achieves spontaneous, rapid, and long-distance transport of viscous liquids. WIDS reduces viscous drag by spatially isolating the viscous liquids and surface roughness through its heterogenous, slippery topological design, and generates capillary forces through its heterogenous wetting distributions. The essential role of surface heterogeneity in viscous liquid transport is theoretically and experimentally verified. Remarkably, such a heterogenous paradigm enables transporting liquids with viscosities exceeding 12 500 mPa s, which is two orders of magnitude higher than state-of-the-art techniques. Furthermore, this heterogenous design is generic for various viscous liquids and can be made flexible, making it promising for various systems that require viscous liquid management, such as micropatterning.

5.
Anal Chem ; 94(49): 17177-17185, 2022 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-36454682

RESUMEN

Due to the fascinating properties such as high porosity, large surface areas, and tunable chemical components, metal-organic frameworks (MOFs) have emerged in many fields including catalysis, energy storage, and gas separation. However, the intrinsic electrical insulation of MOFs severely restricts their application in electrochemistry. Here, we synthesize a series of 2D conductive MOFs (cMOFs) through tuning the structure with atomic precision using simple hydrothermal methods. Various electroactive probes are used to reveal the structure-property relationships in 2D cMOFs. Then, we demonstrate the first exploration and implementation of 2D cMOFs toward the construction of electrochemical biosensors. In particular, the biosensor based on Cu3(tetrahydroxy-1,4-quinone)2 [Cu3(THQ)2] displays a remarkably improved electrocatalytic performance at a much lower potential. The mechanism study reveals the essential role of charge-transfer interactions between the dense catalytic sites of Cu3(THQ)2 and analytes. Furthermore, the Cu3(THQ)2-based biosensor demonstrates robust anti-interference capability, good stability, fast response speed, and an ultralow detection limit for paraoxon. These promising results indicate the great potential of cMOFs in biomedical, food safety, and environmental sensing applications.


Asunto(s)
Técnicas Biosensibles , Estructuras Metalorgánicas , Conductividad Eléctrica , Paraoxon , Catálisis , Electricidad
6.
J Gene Med ; 24(10): e3446, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36027869

RESUMEN

OBJECTIVES: The molecular mechanistic actions of tumor-derived extracellular vesicles (EVs) in modulating macrophage polarization in the tumor microenvironment of epithelial ovarian cancer (EOC) is largely unknown. The study was performed to clarify the effect and downstream mechanism of microRNA-181c-5p (miR-181c-5p)-containing EVs from EOC cells in the M2 polarization of tumor-associated macrophages (TAMs). METHODS: EVs were isolated from normoxic and hypoxic human EOC cells SKOV3. Human mononuclear cell THP-1 was induced by phorbol-12-myristate-13-acetate to differentiate into TAMs. The targeting relationship between miR-181c-5p and KAT2B was verified by dual luciferase reporter gene assay. The interaction between KAT2B and HOXA10 was detected by immunofluorescence, Co-IP and ChIP assays. EdU staining, the scratch test and Transwell assay were used to assess the resultant cell proliferation, migration and invasion. The mouse xenograft model and the pulmonary metastasis model were developed through intraperitoneal injection of SKOV3 cells and tail vein injection of THP-1 cells, respectively. RESULTS: Hypoxic SKOV3 cell-derived EVs could be internalized by TAMs. SKOV3 cell-derived EVs induced by hypoxia (H-EVs) promoted M2 polarization of TAMs and facilitated the proliferation, migration and invasion of SKOV3 cells. miR-181c-5p was highly expressed in H-EVs and promoted the M2 polarization of TAMs. Further, miR-181c-5p targeted KAT2B, upregulated HOXA10 and activated the JAK1/STAT3 pathway, thereby promoting the M2 polarization of TAMs. In both mouse models, H-EV-derived miR-181c-5p promoted growth and metastasis of EOC cells. CONCLUSION: The miR-181c-5p-containing EVs from hypoxic EOC cells may upregulate HOXA10 by targeting KAT2B and activate the JAK1/STAT3 pathway to promote the M2 polarization of TAMs, ultimately promoting growth and metastasis of EOC cells in vitro and in vivo.


Asunto(s)
Vesículas Extracelulares , MicroARNs , Neoplasias Ováricas , Acetatos/metabolismo , Animales , Carcinoma Epitelial de Ovario/genética , Carcinoma Epitelial de Ovario/patología , Línea Celular Tumoral , Vesículas Extracelulares/genética , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/patología , Femenino , Proteínas Homeobox A10 , Humanos , Macrófagos/metabolismo , Macrófagos/patología , Ratones , MicroARNs/genética , MicroARNs/metabolismo , Neoplasias Ováricas/genética , Microambiente Tumoral/genética , Macrófagos Asociados a Tumores , Factores de Transcripción p300-CBP/metabolismo
7.
BMC Musculoskelet Disord ; 23(1): 461, 2022 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-35578265

RESUMEN

BACKGROUND: Implant design for the correction of osteoporotic unstable intertrochanteric fractures in elderly patients is a controversial issue. Our study aims to compare the efficacy of PFNA and cementless bipolar hemiarthroplasty (CBH) in treating osteoporotic unstable intertrochanteric fractures in the elderly. METHODS: We retrospectively assessed 70 elderly patients, aged > 70 years old, with intertrochanteric fractures (AO/OTA 31-A2 fractures) from 2014 to 2019. Among them, 34 patients received PFNA and 36 patients received CBH, accompanied with 2-year follow-ups. Additionally, the efficacy difference between the two implants was compared. RESULTS: Both groups had similar general variables like age, gender, fracture site, degree of osteoporosis, fracture classification, ASA score, basic diseases, preoperative preparation time, anesthesia mode, amount of postoperative blood loss, hospital length of stay, along with postoperative blood transfusions and postoperative complications (P > 0.05). Conversely, significant differences were observed among intraoperative variables (amount of blood loss, amount of blood transfusions, operative time, number of intraoperative fluoroscopy), postoperative variables (weight-bearing time out of bed), and Harris hip function score within 12 months of operation (P < 0.05). CONCLUSIONS: CBH showed no obvious advantage over PFNA in the perioperative period in elderly patients with osteoporotic unstable intertrochanteric fractures. However, the joint replacement allowed for earlier ambulation after the operation and rapid recovery of the hip joint function.


Asunto(s)
Fracturas del Fémur , Fijación Intramedular de Fracturas , Hemiartroplastia , Fracturas de Cadera , Osteoporosis , Fracturas Osteoporóticas , Anciano , Clavos Ortopédicos , Fracturas del Fémur/cirugía , Hemiartroplastia/efectos adversos , Fracturas de Cadera/cirugía , Humanos , Osteoporosis/complicaciones , Osteoporosis/cirugía , Fracturas Osteoporóticas/diagnóstico por imagen , Fracturas Osteoporóticas/cirugía , Estudios Retrospectivos , Resultado del Tratamiento
8.
Sensors (Basel) ; 22(3)2022 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-35161547

RESUMEN

Thin-film silicon (Si)-based transient electronics represents an emerging technology that enables spontaneous dissolution, absorption and, finally, physical disappearance in a controlled manner under physiological conditions, and has attracted increasing attention in pertinent clinical applications such as biomedical implants for on-body sensing, disease diagnostics, and therapeutics. The degradation behavior of thin-film Si materials and devices is critically dependent on the device structure as well as the environment. In this work, we experimentally investigated the dissolution of planar Si thin films and micropatterned Si pillar arrays in a cell culture medium, and systematically analyzed the evolution of their topographical, physical, and chemical properties during the hydrolysis. We discovered that the cell culture medium significantly accelerates the degradation process, and Si pillar arrays present more prominent degradation effects by creating rougher surfaces, complicating surface states, and decreasing the electrochemical impedance. Additionally, the dissolution process leads to greatly reduced mechanical strength. Finally, in vitro cell culture studies demonstrate desirable biocompatibility of corroded Si pillars. The results provide a guideline for the use of thin-film Si materials and devices as transient implants in biomedicine.


Asunto(s)
Electrónica , Silicio , Técnicas de Cultivo de Célula , Indicadores y Reactivos
9.
Plant Cell Environ ; 44(1): 88-101, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32677712

RESUMEN

Germination is a plant developmental process by which radicle of mature seeds start to penetrate surrounding barriers for seedling establishment and multiple environmental factors have been shown to affect it. Little is known how high salinity affects seed germination of C4 plant, Zea mays. Preliminary germination assay suggested that isolated embryo alone was able to germinate under 200 mM NaCl treatment, whereas the intact seeds were highly repressed. We hypothesized that maize endosperm may function in perception and transduction of salt signal to surrounding tissues such as embryo, showing a completely different response to that in Arabidopsis. Since salt response involves ABA, we analysed in vivo ABA distribution and quantity and the result demonstrated that ABA level in isolated embryo under NaCl treatment failed to increase in comparison with the water control, suggesting that the elevation of ABA level is an endosperm dependent process. Subsequently, by using advanced profiling techniques such as RNA sequencing and SWATH-MS-based quantitative proteomics, we found substantial differences in post-transcriptional and translational changes between salt-treated embryo and endosperm. In summary, our results indicate that these regulatory mechanisms, such as alternative splicing, are likely to mediate early responses to salt stress during maize seed germination.


Asunto(s)
Semillas/metabolismo , Cloruro de Sodio/metabolismo , Zea mays/genética , Ácido Abscísico/metabolismo , Perfilación de la Expresión Génica , Redes Reguladoras de Genes/genética , Redes Reguladoras de Genes/fisiología , Giberelinas/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Proteoma , Estrés Salino , Semillas/crecimiento & desarrollo , Zea mays/crecimiento & desarrollo , Zea mays/metabolismo
10.
Nature ; 526(7573): 391-6, 2015 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-26176916

RESUMEN

The major facilitator superfamily glucose transporters, exemplified by human GLUT1-4, have been central to the study of solute transport. Using lipidic cubic phase crystallization and microfocus X-ray diffraction, we determined the structure of human GLUT3 in complex with D-glucose at 1.5 Å resolution in an outward-occluded conformation. The high-resolution structure allows discrimination of both α- and ß-anomers of D-glucose. Two additional structures of GLUT3 bound to the exofacial inhibitor maltose were obtained at 2.6 Å in the outward-open and 2.4 Å in the outward-occluded states. In all three structures, the ligands are predominantly coordinated by polar residues from the carboxy terminal domain. Conformational transition from outward-open to outward-occluded entails a prominent local rearrangement of the extracellular part of transmembrane segment TM7. Comparison of the outward-facing GLUT3 structures with the inward-open GLUT1 provides insights into the alternating access cycle for GLUTs, whereby the C-terminal domain provides the primary substrate-binding site and the amino-terminal domain undergoes rigid-body rotation with respect to the C-terminal domain. Our studies provide an important framework for the mechanistic and kinetic understanding of GLUTs and shed light on structure-guided ligand design.


Asunto(s)
Transportador de Glucosa de Tipo 3/química , Transportador de Glucosa de Tipo 3/metabolismo , Glucosa/química , Glucosa/metabolismo , Sitios de Unión , Transporte Biológico , Membrana Celular/metabolismo , Cristalografía por Rayos X , Transportador de Glucosa de Tipo 1/química , Transportador de Glucosa de Tipo 1/metabolismo , Humanos , Cinética , Ligandos , Maltosa/química , Maltosa/metabolismo , Modelos Moleculares , Unión Proteica , Conformación Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Rotación , Relación Estructura-Actividad
11.
Nature ; 510(7503): 121-5, 2014 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-24847886

RESUMEN

The glucose transporter GLUT1 catalyses facilitative diffusion of glucose into erythrocytes and is responsible for glucose supply to the brain and other organs. Dysfunctional mutations may lead to GLUT1 deficiency syndrome, whereas overexpression of GLUT1 is a prognostic indicator for cancer. Despite decades of investigation, the structure of GLUT1 remains unknown. Here we report the crystal structure of human GLUT1 at 3.2 Å resolution. The full-length protein, which has a canonical major facilitator superfamily fold, is captured in an inward-open conformation. This structure allows accurate mapping and potential mechanistic interpretation of disease-associated mutations in GLUT1. Structure-based analysis of these mutations provides an insight into the alternating access mechanism of GLUT1 and other members of the sugar porter subfamily. Structural comparison of the uniporter GLUT1 with its bacterial homologue XylE, a proton-coupled xylose symporter, allows examination of the transport mechanisms of both passive facilitators and active transporters.


Asunto(s)
Transportador de Glucosa de Tipo 1/química , Errores Innatos del Metabolismo de los Carbohidratos/genética , Cristalografía por Rayos X , Proteínas de Escherichia coli , Transportador de Glucosa de Tipo 1/deficiencia , Transportador de Glucosa de Tipo 1/genética , Transportador de Glucosa de Tipo 1/metabolismo , Humanos , Ligandos , Modelos Biológicos , Modelos Moleculares , Proteínas de Transporte de Monosacáridos/deficiencia , Proteínas de Transporte de Monosacáridos/genética , Mutación/genética , Estructura Terciaria de Proteína , Relación Estructura-Actividad , Simportadores
12.
J Biol Chem ; 293(50): 19492-19500, 2018 12 14.
Artículo en Inglés | MEDLINE | ID: mdl-30333234

RESUMEN

Acetate is found ubiquitously in the natural environment and can be used as an exogenous carbon source by bacteria, fungi, and mammalian cells. A representative member of the acetate uptake transporter (AceTr) family named SatP (also yaaH) has been preliminarily identified as a succinate-acetate/proton symporter in Escherichia coli However, the molecular mechanism of acetate uptake by SatP still remains elusive. Here, we report the crystal structure of SatP from E. coli at 2.8 Å resolution, determined with a molecular replacement approach using a previously developed predicted model algorithm, which revealed a hexameric UreI-like channel structure. Structural analysis identified six transmembrane (TM) helices surrounding the central channel pore in each protomer and three conserved hydrophobic residues, FLY, located in the middle of the TM region for pore constriction. According to single-channel conductance recordings, performed with purified SatP reconstituted into lipid bilayer, three conserved polar residues in the TM1 facing to the periplasmic side are closely associated with acetate translocation activity. These analyses provide critical insights into the mechanism of acetate translocation in bacteria and a first glimpse of a structure of an AceTr family transporter.


Asunto(s)
Proteínas de Escherichia coli/química , Transportadores de Anión Orgánico/química , Multimerización de Proteína , Sitios de Unión , Cristalografía por Rayos X , Escherichia coli , Proteínas de Escherichia coli/metabolismo , Modelos Moleculares , Transportadores de Anión Orgánico/metabolismo , Estructura Cuaternaria de Proteína
13.
Nano Lett ; 17(11): 6893-6899, 2017 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-29053279

RESUMEN

Li-iodine chemistry is of interest for electrochemical energy storage because it has been shown to provide both high power and high energy density. However, Li-iodine batteries are typically formed using Li metal and elemental iodine, which presents safety and fabrication challenges (e.g., the high vapor pressure of iodine). These disadvantages could be circumvented by using LiI as a starting cathode. Here, we present fabrication of a reduced graphene oxide (rGO)/LiI composite cathode, enabling for the first time the use of LiI as the Li-ion battery cathode. LiI was coated on rGO by infiltration of an ethanolic solution of LiI into a compressed rGO aerogel followed by drying. The free-standing rGO/LiI electrodes show stable long-term cycling and good rate performance with high specific capacity (200 mAh g-1 at 0.5 C after 100 cycles) and small hysteresis (0.056 V at 1 C). Shuttling was suppressed significantly. We speculate the improved electrochemical performance is due to strong interactions between the active materials and rGO, and the reduced ion and electron transport distances provided by the three-dimensional structured cathode.

14.
Cell Physiol Biochem ; 42(6): 2582-2592, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28848113

RESUMEN

BACKGROUND/AIMS: Lemur tyrosine kinase (LMTK)-3 is a member of the receptor tyrosine kinase (RTK) family. Abnormal expression of LMTK-3 exists in various types of cancers, especially in endocrine-resistant breast cancers; however, the precise level of expression and the biological function in prostate cancer are poorly understood. METHODS: In the present study, we determined the expression of LMTK-3 in prostate cancer using immunohistochemistry and Western blotting. We infected PC3 and LNCaP cells with lentivirus-LMTK-3 and observed the biologic characteristics of the PC3 and LNCaP cells in vitro with TUNEL, and migration and invasion assays, respectively. We also established a transplant tumor model of human prostate cancer with infected cells in 15 BALB/c-nu/nu nude mice. RESULTS: LMTK-3 was expressed in prostate epithelial cells. There was a significant decline in the level of LMTK-3 expression in prostate cancers compared to normal tissues. LMTK-3 inhibited PC3 and LNCaP cell growth, migration, and invasion, and induced cell apoptosis in vitro. We also observed that LMTK-3 induced PC3 cell apoptosis in vivo. Further study showed that LMTK-3 inhibited phosphorylation of AKT and ERK, and promoted phosphorylation and activation of p38 kinase and Jun kinase (JNK). CONCLUSION: Recombinant lentivirus with enhanced expression of LMTK-3 inhibited prostate cancer cell growth and induced apoptosis in vitro and in vivo. AKT and MAPK signaling pathways may contribute to the process.


Asunto(s)
Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Proteínas de la Membrana/metabolismo , Neoplasias de la Próstata/patología , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Anciano , Anciano de 80 o más Años , Animales , Apoptosis , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Vectores Genéticos/genética , Vectores Genéticos/metabolismo , Humanos , Lentivirus/genética , Sistema de Señalización de MAP Quinasas , Masculino , Proteínas de la Membrana/antagonistas & inhibidores , Proteínas de la Membrana/genética , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Persona de Mediana Edad , Neoplasias de la Próstata/metabolismo , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/genética , Trasplante Heterólogo
15.
Nano Lett ; 16(7): 4501-7, 2016 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-27322627

RESUMEN

High volumetric energy density secondary batteries are important for many applications, which has led to considerable efforts to replace the low volumetric capacity graphite-based anode common to most Li-ion batteries with a higher energy density anode. Because most high capacity anode materials expand significantly during charging, such anodes must contain sufficient porosity in the discharged state to enable the expansion, yet not excess porosity, which lowers the overall energy density. Here, we present a high volumetric capacity anode consisting of a three-dimensional (3D) nanocomposite formed in only a few steps which includes both a 3D structured Sn scaffold and a hollow Sn sphere within each cavity where all the free Sn surfaces are coated with carbon. The anode exhibits a high volumetric capacity of ∼1700 mA h cm(-3) over 200 cycles at 0.5C, and a capacity greater than 1200 mA h cm(-3) at 10C. Importantly, the anode can even be formed into a commercially relevant ∼100 µm thick form. When assembled into a full cell the anode shows a good compatibility with a commercial LiMn2O4 cathode. In situ TEM observations confirm the electrode design accommodates the necessary volume expansion during lithiation.

16.
Environ Sci Pollut Res Int ; 31(22): 32725-32745, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38662295

RESUMEN

Ecosystem carbon storage (ECS) is a critical consideration in reducing the impact of global warming and tackling environmental challenges, positioning it at the forefront of contemporary research. Due to the significant differences in the influence of land usage patterns on ECS in various policy contexts and China's commitment to attaining a carbon-neutral status, a model simulating different scenarios is needed to analyze the spatiotemporal characteristics and evolutionary process of carbon storage in terrestrial ecosystems accurately. To address this challenge, this study established a coupling model of "Geographical analysis -Evolution analysis -Predicting (GEP)" for assessing ecosystem ECS and analyzing its spatial characteristics and evolutionary patterns and projecting the spatial distribution of ECS under various developmental scenarios, which analyzed variations in ECS across different levels of magnitude and delineated the changing areas across a range of varying scenarios in the future additionally. The outcomes suggested that the ECS decreased by 1.17 × 106 t from 1990 to 2020, which pertaining to the utilization transfer of land in the area, whose change in ECS levels with a positive trend. It is predicted that the ECS will grow by 1.15 × 106 t and 1.44 × 106 t, in 2030 and 2060 compared with 2020 within the framework of natural development scenario (NDS), while within the framework of ecological protection scene (EPS), ECS will increase significantly, increasing by 3.06 × 106 t and 4.44 × 106 t. There will be more areas where ECS increases within the framework of EPS, by comparing with the NDS. This study offers a comprehensive analysis of Hanzhong City's carbon storage trends, demonstrating its significant impact on climate change mitigation and serving as a predictive model for similar regions, which underscores the importance of localized carbon management strategies, offering valuable insights for local governments in formulating effective climate adaptation and mitigation policies.


Asunto(s)
Ecosistema , China , Carbono , Secuestro de Carbono , Modelos Teóricos , Calentamiento Global
17.
Artículo en Zh | MEDLINE | ID: mdl-38686478

RESUMEN

Objective:To summarize the clinical characteristics and therapeutic effect of traumatic facial nerve palsy. Methods:Sixty-eight cases of traumatic facial nerve palsy were retrospectively analyzed from January 2015 to May 2023. Results:The median course of disease was 33 days. The facial nerve function of the patients was grade HB-Ⅱin 2 cases, grade HB-Ⅲ in 4 cases, grade HB-Ⅳin 16 cases, grade HB-Ⅴ in 37 cases(38 ears), and grade HB-Ⅵ in 9 cases. 42 cases occurred immediately after injury and 26 cases were delayed. CT examination of temporal bone revealed longitudinal fractures in 51 cases(52 ears) , transverse fractures in 6 cases and mixed fractures in 4 cases. No definite temporal bone fracture was found in the remaining 7 cases. The segments of facial nerve injury in 49 cases(50 ears) were geniculate ganglion and adjacent, in 7 cases were vertical segment, in 7 cases were horizontal segment, in 2 cases were horizontal segment and vertical segment; and the other 3 cases could not be evaluated. Conservative treatment with glucocorticoids was used in 23 ears and surgery was used in 46 ears. Patients were followed up 6-24 months after treatment, including 20 cases of grade HB-Ⅰ, 19 cases of grade HB-Ⅱ, 23 cases(24 ears) of grade HB-Ⅲ, 4 cases of grade HB-Ⅳ, and 1 case of grade HB-Ⅴ.One patient was lost to follow-up. After treatment, the facial nerve function of patients was significantly improved(P<0.05), and there were significant differences between conservative treatment group and surgical treatment group in the course of facial nerve palsy, the ratio of facial palsy immediately after injury, the nerve function before treatment and the nerve function after treatment(P<0.05). There were no significant differences in age, sex, hearing condition, temporal bone fracture, facial nerve injury segment and rate of favorable neurologic outcomes(P>0.05). The comparison of patients with neurodegeneration rate>90% and ≤90% showed that the facial nerve function of patients with neurodegeneration rate>90% before treatment was significantly worse(P<0.05), but there was no significant difference between the facial nerve function after treatment(P>0.05). There was no significant difference in facial nerve function between middle fossa approach group and mastoid approach group(P>0.05). Conclusion:Patients with traumatic facial nerve palsy should be evaluated individually. Patients with mild facial nerve palsy, low neurodegeneration rate and short course of disease can be treated conservatively and followed up closely. Patients with severe facial nerve palsy, high neurodegeneration rate and more than 6 weeks of disease can be actively considered surgery. Good prognosis can be obtained by correct evaluation and treatment.


Asunto(s)
Traumatismos del Nervio Facial , Parálisis Facial , Humanos , Parálisis Facial/etiología , Parálisis Facial/diagnóstico , Parálisis Facial/terapia , Estudios Retrospectivos , Masculino , Femenino , Traumatismos del Nervio Facial/terapia , Traumatismos del Nervio Facial/diagnóstico , Adulto , Persona de Mediana Edad , Adulto Joven , Adolescente , Hueso Temporal/lesiones , Nervio Facial , Glucocorticoides/uso terapéutico , Resultado del Tratamiento
18.
Medicine (Baltimore) ; 103(18): e38052, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38701256

RESUMEN

The purpose of this study is to investigate the potential mechanisms of Chinese herbs for the treatment of insomnia using a combination of data mining, network pharmacology, and molecular-docking validation. All the prescriptions for insomnia treated by the academician Qi Wang from 2020 to 2022 were collected. The Ancient and Modern Medical Case Cloud Platform v2.3 was used to identify high-frequency Chinese medicinal herbs and the core prescription. The Traditional Chinese Medicine Systems Pharmacology and UniProt databases were utilized to predict the effective active components and targets of the core herbs. Insomnia-related targets were collected from 4 databases. The intersecting targets were utilized to build a protein-protein interaction network and conduct gene ontology enrichment analysis and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis using the STRING database, Cytoscape software, and clusterProfiler package. Gene chip data (GSE208668) were obtained from the Gene Expression Omnibus database. The limma package was applied to identify differentially expressed genes (DEGs) between insomnia patients and healthy controls. To create a "transcription factor (TF)-miRNA-mRNA" network, the differentially expressed miRNAs were entered into the TransmiR, FunRich, Targetscan, and miRDB databases. Subsequently, the overlapping targets were validated using the DEGs, and further validations were conducted through molecular docking and molecular dynamics simulations. Among the 117 prescriptions, 65 herbs and a core prescription were identified. Network pharmacology and bioinformatics analysis revealed that active components such as ß-sitosterol, stigmasterol, and canadine acted on hub targets, including interleukin-6, caspase-3, and hypoxia-inducible factor-1α. In GSE208668, 6417 DEGs and 7 differentially expressed miRNAs were identified. A "TF-miRNA-mRNA" network was constructed by 4 "TF-miRNA" interaction pairs and 66 "miRNA-mRNA" interaction pairs. Downstream mRNAs exert therapeutic effects on insomnia by regulating circadian rhythm. Molecular-docking analyses demonstrated good docking between core components and hub targets. Molecular dynamics simulation displayed the strong stability of the complex formed by small molecule and target. The core prescription by the academician Qi Wang for treating insomnia, which involves multiple components, targets, and pathways, showed the potential to improve sleep, providing a basis for clinical treatment of insomnia.


Asunto(s)
Medicamentos Herbarios Chinos , Medicina Tradicional China , MicroARNs , Simulación del Acoplamiento Molecular , Farmacología en Red , Mapas de Interacción de Proteínas , Trastornos del Inicio y del Mantenimiento del Sueño , Trastornos del Inicio y del Mantenimiento del Sueño/tratamiento farmacológico , Trastornos del Inicio y del Mantenimiento del Sueño/genética , Humanos , Medicamentos Herbarios Chinos/uso terapéutico , Medicamentos Herbarios Chinos/farmacología , Medicina Tradicional China/métodos , Redes Reguladoras de Genes/efectos de los fármacos , ARN Mensajero/metabolismo , ARN Mensajero/genética , Minería de Datos , Factores de Transcripción/genética
19.
Artículo en Inglés | MEDLINE | ID: mdl-38808528

RESUMEN

Background: Duodenal stump fistula represents an infrequent but serious complication after laparoscopic radical gastrectomy with Billroth II or Roux-en-Y reconstruction for gastric cancer. The present study was designed to evaluate the effectiveness of laparoscopic double half purse-string sutures plus "8" pattern of stitching for reinforcement of duodenal stump. Methods: The data of patients undergoing laparoscopic radical gastrectomy with Billroth II or Roux-en-Y reconstruction were retrospectively analyzed between August 2022 and June 2023. According to the different reinforcement methods of duodenal stump, included patients were subdivided into three groups as follows: Group A, duodenal stump was treated with double half purse-string sutures plus "8" pattern of stitching; Group B, duodenal stump was reinforced by continuous suture using a barbed suture; and Group C, duodenal stump without any additional processing. The incidences of duodenal stump fistula between three groups were documented and compared. Moreover, the independent risk factors associated with duodenal stump fistula were analyzed using the logistic regression analysis. Results: No postoperative duodenal stump fistula occurred in Group A, which was significantly different from Group B and Group C (P = .007). In the multivariate analysis, age (odds ratio [OR], 1.191; 95% confidence interval [CI], 1.088-1.303), body mass index (OR, 0.824; 95% CI, 0.727-0.935), and American Society of Anesthesiologists score (OR, 4.495; 95% CI, 1.264-15.992) were the risk factors for duodenal stump fistula. Conclusion: Double half purse-string sutures plus "8" pattern of suture can be conducted in a relatively short operation period and could prevent the incidence of duodenal stump fistula to some extent.

20.
Front Genet ; 15: 1242974, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38699230

RESUMEN

Background: Allergic rhinitis (AR) is a widespread allergic airway disease that results from a complex interplay between genetic and environmental factors and affects approximately 10%-40% of the global population. Pollen is a common allergen, and exposure to pollen can cause epigenetic changes. However, the mechanism underlying pollen-induced DNA methylation changes and their potential effects on the allergic march are still unclear. The purpose of this study was to explore the methylation-driven mechanisms of AR during the pollen and non-pollen seasons using bioinformatics analysis and to investigate their relationship with asthma. Methods: We downloaded DNA methylation and gene expression data from the GEO database (GSE50387: GSE50222, GSE50101) and identified differentially methylated positions (DMPs) and differentially expressed genes (DEGs) during the pollen and non-pollen seasons using the CHAMP and limma packages. Through correlation analysis, we identified methylation-driven genes and performed pathway enrichment analysis to annotate their functions. We incorporated external data on AR combined with asthma (GSE101720) for analysis to identify key CpGs that promote the transformation of AR to asthma. We also utilized external data on olive pollen allergy (GSE54522) for analysis to validate the methylation-driven genes. Weighted correlation network analysis (WGCNA) was employed to identify gene modules significantly correlated with pollen allergy. We extracted genes related to the key methylation-driven gene ZNF667-AS1 from the significant module and performed pathway intelligent clustering using KOBAS-i. We also utilized gene set enrichment analysis to explore the potential function of ZNF667-AS1. Results: We identified 20 and 24 CpG-Gene pairings during the pollen and non-pollen seasons. After incorporating external data from GSE101720, we found that ZNF667-AS1 is a key gene that may facilitate the transformation of AR into asthma during the pollen season. This finding was further validated in another external dataset, GSE54522, which is associated with pollen allergy. WGCNA identified 17 modules, among which the blue module showed significant correlation with allergies. ZNF667-AS1 was located in the blue module. We performed pathway analysis on the genes correlated with ZNF667-AS1 extracted from the blue module and identified a prominent cluster of pathways in the KOBAS-i results, including Toll-like receptor (TLR) family, MyD88, MAPK, and oxidative stress. Gene set enrichment analysis around cg05508084 (paired with ZNF667-AS1) also indicated its potential involvement in initiating and modulating allergic inflammation from the perspective of TLR and MAPK signaling. Conclusion: We identified methylation-driven genes and their related pathways during the pollen and non-pollen seasons in patients with AR and identified key CpGs that promote the transformation of AR into asthma due to pollen exposure. This study provides new insights into the underlying molecular mechanisms of the transformation of AR to asthma.

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