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1.
Medicine (Baltimore) ; 103(37): e39421, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39287270

RESUMEN

OBJECTIVE: To evaluate the effect of diagnosis-related group (DRG) payment method systematically before and after implementation in terms of average hospitalization day, cost and care quality. METHOD: Restricted the period from 2019 to May 31, 2023, we use 6 databases from CNKI, Wipu, Wanfang, PubMed, ScienceDirect, and web of science. With the related study, we extract the data about DRG, then we conducted meta-analysis of the data about length of stay (LOS) and cost by RevMan 5.4 and Stata 12.0 software. Care quality is in conjunction with literature reports. RESULT: About 24 articles were included, covering 2 indicators: average hospitalization expenses and days. Meta-analysis shows that implementing DRG payment method has an advantage in terms of average hospital stay (pooled effect: -1.13%, 95% CI: -1.42 to -0.84, P = .00), and the difference is statistically significant. There is also an advantage in average hospitalization expenses (pooled effect: -2.58, 95% CI: -3.38 to -1.79, P = .00), and the difference is statistically significant. CONCLUSION: The use of DRG payment method can effectively reduce LOS and average hospitalization expenses. However, quality of care may decline with DRG adoption.


Asunto(s)
Grupos Diagnósticos Relacionados , Hospitalización , Tiempo de Internación , Humanos , Tiempo de Internación/economía , Tiempo de Internación/estadística & datos numéricos , Grupos Diagnósticos Relacionados/economía , Hospitalización/economía , Hospitalización/estadística & datos numéricos , Control de Costos/métodos , Costos de Hospital/estadística & datos numéricos , Calidad de la Atención de Salud/economía
2.
Ecol Evol ; 14(9): e70314, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39279795

RESUMEN

The global climate change has resulted in substantial modifications to the distribution patterns of narrowly distributed species across different time periods, leading to an imminent threat to the survival of some vulnerable species. Chimonobambusa tumidissinoda J. R. Xue & T. P. Yi ex Ohrnb., a bamboo species endemic to the transition zone from the Yunnan-Guizhou Plateau to the Sichuan Basin with high economic and ecological value, exhibits a limited range and rarity. Utilizing eight environmental variables and 56 occurrence records, we employed the MaxEnt model to predict the potential distribution range of C. tumidissinoda under current and future climate scenarios. The findings revealed that precipitation of the driest month (Bio14), elevation and isothermality (Bio3) were the crucial factors determining the species' distribution, accounting for 31.24%, 28.27% and 17.24% of data variability, respectively. The distribution centroid of C. tumidissinoda is anticipated to shift towards higher latitudes in response to future climate change, and the projected habitat suitability is expected to expand under ssp245 and ssp585 scenarios while remaining unchanged or contracting under the ssp126 scenario. Despite these expansions, the suitable habitats remain limited, with the largest being approximately 2.08 × 104 km2, indicating a significant threat to its survival. Our study provides insights into the adaptive responses of C. tumidissinoda to climate change, enriching scientific knowledge for developing effective conservation measurements as well as sustainable utilization.

3.
Nanoscale ; 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39225229

RESUMEN

Theoretically determining the lowest-energy structure of a cluster has been a persistent challenge due to the inherent difficulty in accurate description of its potential energy surface (PES) and the exponentially increasing number of local minima on the PES with the cluster size. In this work, density-functional theory (DFT) calculations of Co clusters were performed to construct a dataset for training deep neural networks to deduce a deep potential (DP) model with near-DFT accuracy while significantly reducing computational consumption comparable to classic empirical potentials. Leveraging the DP model, a high-efficiency hybrid differential evolution (HDE) algorithm was employed to search for the lowest-energy structures of CoN (N = 11-50) clusters. Our results revealed 38 of these clusters superior to those recorded in the Cambridge Cluster Database and identified diverse architectures of the clusters, evolving from layered structures for N = 11-27 to Marks decahedron-like structures for N = 28-42 and to icosahedron-like structures for N = 43-50. Subsequent analyses of the atomic arrangement, structural similarity, and growth pattern further verified their hierarchical structures. Meanwhile, several highly stable clusters, i.e., Co13, Co19, Co22, Co39, and Co43, were discovered by the energetic analyses. Furthermore, the magnetic stability of the clusters was verified, and a competition between the coordination number and bond length in affecting the magnetic moment was observed. Our study provides high-accuracy and high-efficiency prediction of the optimal structures of clusters and sheds light on the growth trend of Co clusters containing tens of atoms, contributing to advancing the global optimization algorithms for effective determination of cluster structures.

4.
Heliyon ; 10(16): e36170, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39224351

RESUMEN

To address rotor imbalance and misalignment in oil transfer pumps, an innovative diagnostic framework using Residual Network (ResNet) is proposed. The model incorporates advanced signal processing algorithms and strategic sensor placement to enhance diagnostic efficacy. A fault simulation test rig captured vibration signals from eight key measurement points on the pump. One-dimensional and multi-dimensional signal processing techniques generated comprehensive datasets for training and validating the model. Sensor placement optimization, focusing on the bearing seat's axial direction, inlet flange's vertical direction, and outlet flange's axial direction, increased rotor fault sensitivity. Time-frequency data processed via Short-Time Fourier Transform (STFT) achieved the highest diagnostic accuracy, surpassing 98 %. This study highlights the importance of optimal signal processing and precise sensor placement in improving the accuracy of diagnosing rotor faults in oil transfer pumps, thus enhancing the operational reliability and efficiency of energy transportation systems.

5.
Nat Commun ; 15(1): 7624, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39223157

RESUMEN

Metal-oxide interfaces with poor coherency have specific properties comparing to bulk materials and offer broad applications in heterogeneous catalysis, battery, and electronics. However, current understanding of the three-dimensional (3D) atomic metal-oxide interfaces remains limited because of their inherent structural complexity and the limitations of conventional two-dimensional imaging techniques. Here, we determine the 3D atomic structure of metal-oxide interfaces in zirconium-zirconia nanoparticles using atomic-resolution electron tomography. We quantitatively analyze the atomic concentration and the degree of oxidation, and find the coherency and translational symmetry of the interfaces are broken. Atoms at the interface have low structural ordering, low coordination, and elongated bond length. Moreover, we observe porous structures such as Zr vacancies and nano-pores, and investigate their distribution. Our findings provide a clear 3D atomic picture of metal-oxide interface with direct experimental evidence. We anticipate this work could encourage future studies on fundamental problems of oxides, such as interfacial structures in semiconductor and atomic motion during oxidation process.

7.
Int J Obes (Lond) ; 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39237758

RESUMEN

BACKGROUND/AIMS: Elevated systemic inflammation, common in obesity, increases cardiovascular disease risk. Obesity is linked to a pro-inflammatory gut microbiota that releases uremic toxins like p-cresylsulfate (PCS) and indoxyl sulfate (IS), which are implicated in coronary atherosclerosis, insulin resistance, and chronic kidney disease. This study examines the relationship between total PCS and IS levels and central obesity in patients with stable coronary artery disease (CAD). METHODS: A cross-sectional study was conducted on 373 consecutive patients with stable CAD from a single center. Serum levels of total PCS and IS were measured using an Ultra Performance LC System. Central obesity was evaluated using a body shape index (ABSI) and conicity index (CI). Six obesity-related proteins were also analyzed. Structural equation modeling (SEM) assessed direct and indirect effects of total PCS, IS, and the six obesity-related proteins on central obesity. RESULTS: Significant positive correlations were found between total PCS and IS with waist-to-hip ratio (WHR) (r = 0.174, p = 0.005 for total PCS; r = 0.144, p = 0.021 for IS), CI (r = 0.273, p < 0.0001 for total PCS; r = 0.260, p < 0.0001 for IS), and ABSI (r = 0.297, p < 0.0001 for total PCS; r = 0.285, p < 0.0001 for IS) in male patients, but not in female patients. Multivariate analysis showed higher odds ratios (ORs) for elevated CI (OR = 3.18, 95% CI: 1.54-6.75, p = 0.002) and ABSI (OR = 3.28, 95% CI: 1.54-7.24, p = 0.002) in patients with high PCS levels, and elevated CI (OR = 2.30, 95% CI: 1.15-4.66, p = 0.018) and ABSI (OR = 2.22, 95% CI: 1.07-4.72, p = 0.033) in those with high IS levels, compared to those with low toxin levels. SEM analysis indicated that total PCS and IS directly impacted central obesity indices and indirectly influenced central adiposity measures like WHR through high sensitivity C-reactive protein (hs-CRP) (ß = 0.252, p < 0.001). CONCLUSIONS: Circulating total PCS and IS contribute to central obesity in male patients with stable CAD, partially mediated by hs-CRP.

8.
Microbiome ; 12(1): 163, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39232827

RESUMEN

BACKGROUND: Our facial skin hosts millions of microorganisms, primarily bacteria, crucial for skin health by maintaining the physical barrier, modulating immune response, and metabolizing bioactive materials. Aging significantly influences the composition and function of the facial microbiome, impacting skin immunity, hydration, and inflammation, highlighting potential avenues for interventions targeting aging-related facial microbes amidst changes in skin physiological properties. RESULTS: We conducted a multi-center and deep sequencing survey to investigate the intricate interplay of aging, skin physio-optical conditions, and facial microbiome. Leveraging a newly-generated dataset of 2737 species-level metagenome-assembled genomes (MAGs), our integrative analysis highlighted aging as the primary driver, influencing both facial microbiome composition and key skin characteristics, including moisture, sebum production, gloss, pH, elasticity, and sensitivity. Further mediation analysis revealed that skin characteristics significantly impacted the microbiome, mostly as a mediator of aging. Utilizing this dataset, we uncovered two consistent cutotypes across sampling cities and identified aging-related microbial MAGs. Additionally, a Facial Aging Index (FAI) was formulated based on the microbiome, uncovering the cutotype-dependent effects of unhealthy lifestyles on skin aging. Finally, we distinguished aging related microbial pathways influenced by lifestyles with cutotype-dependent effect. CONCLUSIONS: Together, our findings emphasize aging's central role in facial microbiome dynamics, and support personalized skin microbiome interventions by targeting lifestyle, skin properties, and aging-related microbial factors. Video Abstract.


Asunto(s)
Bacterias , Cara , Microbiota , Envejecimiento de la Piel , Piel , Humanos , Piel/microbiología , Cara/microbiología , Persona de Mediana Edad , Envejecimiento de la Piel/fisiología , Femenino , Adulto , Masculino , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Anciano , Envejecimiento , Metagenoma , Adulto Joven , Secuenciación de Nucleótidos de Alto Rendimiento , Sebo/metabolismo
10.
Eur J Pharmacol ; 983: 176968, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39233039

RESUMEN

Compound 5p is a 4ß-N-substituted podophyllotoxin derivative, which exhibited potent activity toward drug-resistant K562/A02 cells and decreased MDR-1 mRNA expression. Here, we further investigated its detail mechanism and tested its antitumor activity. 5p exerted catalytic inhibition of topoisomerase IIα, and didn't show the inhibitor of topoisomerase I. 5p exhibited the inhibitory effect on microtubule polymerization. 5p showed potent anti-proliferation against breast cancer, oral squamous carcinoma, and their drug-resistant cell lines, with resistance index of 0.61 and 0.86, respectively. 5p downregulated the expression levels of P-gp in KBV200 cells and BCRP in MCF7/ADR cells in dose-dependent manner. Moreover, 5p induced KB and KBV200 cells arrest at G2/M phase by up-regulating the expression of γ-H2AX, p-Histone H3 and cyclin B1. 5p induced apoptosis and pyroptosis by increased the expression levels of cleaved-PARP, cleaved-caspase3, N-GSDME as well as LDH release in KB and KBV200 cells. In addition, 5p efficiently impaired tumor growth in KB and KBV200 xenograft mice. Conclusively, this work elucidated the dual inhibitor of topoisomerase II and microtubule of 5p and its mechanism of overcoming the multidrug resistance, indicating that 5p exerts the antitumor potentiality.

11.
Angew Chem Int Ed Engl ; : e202411217, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39103975

RESUMEN

Hole-transporting materials (HTMs) are crucial for obtaining the stability and high efficiency of perovskite solar cells (PSCs). However, the current state-of-the-art n-i-p PSCs relied on the use of 2,2',7,7'-tetrakis(N,N-di-p-methoxyphenylamine)-9,9'-spirobifluorene (spiro-OMeTAD) exhibit inferior intrinsic and ambient stability due to the p-dopant and hydrophilic Li-TFSI additive. In this study, a new spiro-type HTM with a critical quasi-planar core (Z-W-03) is developed to improve both the thermal and ambient stability of PSCs. The results suggest that the planar carbazole structure effectively passivates the trap states compared to the triphenylamine with a propeller-like conformation in spiro-OMeTAD. This passivation effect leads to the shallower trap states when the quasi-planar HTMs interact with the Pb-dimer. Consequently, the device using Z-W-03 achieves a higher Voc of 1.178 V compared to the spiro-OMeTAD's 1.155 V, resulting in an enhanced efficiency of 24.02%. In addition, the double-column π-π stacking of Z-W-03 results in high hole mobility (~10-4 cm2 V-1 s-1) even without p-dopant. Moreover, when the surface interface is modified, the undoped Z-W-03 device can achieve an efficiency of nearly 23%. Compared to the PSCs using spiro-OMeTAD, those with Z-W-03 exhibit enhanced stability under N2 and ambient conditions.

12.
Stem Cell Res Ther ; 15(1): 247, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39113140

RESUMEN

BACKGROUND: The role of periodontal ligament stem cells (PDLSCs) in repairing periodontal destruction is crucial, but their functions can be impaired by excessive oxidative stress (OS). Nocardamine (NOCA), a cyclic siderophore, has been shown to possess anti-cancer and anti-bacterial properties. This study aimed to investigate the protective mechanisms of NOCA against OS-induced cellular dysfunction in PDLSCs. METHODS: The cytotoxicity of NOCA on PDLSCs was assessed using a CCK-8 assay. PDLSCs were then treated with hydrogen peroxide (H2O2) to induce OS. ROS levels, cell viability, and antioxidant factor expression were analyzed using relevant kits after treatment. Small molecule inhibitors U0126 and XAV-939 were employed to block ERK signaling and Wnt pathways respectively. Osteogenic differentiation was assessed using alkaline phosphatase (ALP) activity staining and Alizarin Red S (ARS) staining of mineralized nodules. Expression levels of osteogenic gene markers and ERK pathway were determined via real-time quantitative polymerase chain reaction (RT-qPCR) or western blot (WB) analysis. ß-catenin nuclear localization was examined by western blotting and confocal microscopy. RESULTS: NOCA exhibited no significant cytotoxicity at concentrations below 20 µM and effectively inhibited H2O2-induced OS in PDLSCs. NOCA also restored ALP activity, mineralized nodule formation, and the expression of osteogenic markers in H2O2-stimulated PDLSCs. Mechanistically, NOCA increased p-ERK level and promoted ß-catenin translocation into the nucleus; however, blocking ERK pathway disrupted the osteogenic protection provided by NOCA and impaired its ability to induce ß-catenin nuclear translocation under OS conditions in PDLSCs. CONCLUSIONS: NOCA protected PDLSCs against H2O2-induced OS and effectively restored impaired osteogenic differentiation in PDLSCs by modulating the ERK/Wnt signaling pathway.


Asunto(s)
Diferenciación Celular , Peróxido de Hidrógeno , Osteogénesis , Estrés Oxidativo , Ligamento Periodontal , Células Madre , Ligamento Periodontal/citología , Ligamento Periodontal/metabolismo , Ligamento Periodontal/efectos de los fármacos , Humanos , Estrés Oxidativo/efectos de los fármacos , Células Madre/metabolismo , Células Madre/efectos de los fármacos , Peróxido de Hidrógeno/farmacología , Peróxido de Hidrógeno/toxicidad , Osteogénesis/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , beta Catenina/metabolismo , Supervivencia Celular/efectos de los fármacos , Vía de Señalización Wnt/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Células Cultivadas , Especies Reactivas de Oxígeno/metabolismo
13.
J Asian Nat Prod Res ; : 1-7, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39093992

RESUMEN

Four isocoumarin derivatives (1-4) and five phenols (5-9) were obtained from the endophytic fungus Pezicula neosporulosa VDB39, which was isolated from the branches of Vaccinium dunalianum Wight (Ericaceae). Compound 1 is a new derivative of isocoumarin. The structures were elucidated by spectroscopic methods. Single X-ray crystallography confirmed the absolute configuration of compound 1. Additionally, the antiphytopathogenic fungi activity of isocoumarin derivatives (1-4) was evaluated.

14.
Cancer Sci ; 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39192543

RESUMEN

Plasma levels of oncofetal chondroitin sulfate (ofCS)-modified CD44 have emerged as a promising biomarker for multi-cancer detection. Here, we explored its potential to predict the survival of patients with lung cancer. A prospective observational cohort was conducted involving 274 newly diagnosed patients with lung cancer at the Sun Yat-sen University Cancer Center from 2013 to 2015. The plasma levels of ofCS-modified CD44 were measured, and Cox regression analysis was performed to assess the association between plasma-modified CD44 levels and overall survival (OS) as well as other prognostic outcomes. Prognostic nomograms were constructed based on plasma ofCS-modified CD44 levels to predict survival outcomes for patients with lung cancer. Patients with high expression ofCS-modified CD44 exhibited significantly worse outcomes in terms of OS (HR = 1.61, 95%CI = 1.13-2.29, p = 0.009) and progression-free survival (PFS). These findings were consistent across various analyses. The concordance index of the prognostic nomogram for predicting OS in both the training set and validation set were 0.723 and 0.737, respectively. Additionally, time-dependent receiver operating characteristic (ROC) curves showed that the nomogram could serve as a useful tool for predicting OS in patients with lung cancer. Plasma ofCS-modified CD44 may serve as an independent prognosis marker for patients with lung cancer. Further validation of its predictive value could enhance prognostic assessment and guide personalized treatment strategies for patients with lung cancer.

15.
ACS Nano ; 18(34): 23508-23517, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39137306

RESUMEN

Two-dimensional ferromagnetic/antiferromagnetic (2D-FM/AFM) heterostructures are of great significance to realize the application of spintronic devices such as miniaturization, low power consumption, and high-density information storage. However, traditional mechanical stacking can easily damage the crystal quality or cause chemical contamination residues for 2D materials, which can result in weak interface coupling and difficulty in device regulation. Chemical vapor deposition (CVD) is an effective way to achieve a high-quality heterostructure interface. Herein, high-quality interface 2D-FM/AFM Cr7Te8/MnTe vertical heterostructures were successfully synthesized via a one-pot CVD method. Moreover, the atomic-scale structural scanning transmission electron microscope (STEM) characterization shows that the interface of the vertical heterostructure is clear and flat without an excess interface layer. Compared to the parent Cr7Te8, the coercivity (HC) of the high-quality interface Cr7Te8/MnTe heterostructure is significantly reduced as the thickness of MnTe increases, with a maximum decrease of 74.5% when the thickness of the MnTe nanosheet is around 30 nm. Additionally, the HC of the Cr7Te8/MnTe heterostructure can also be regulated by applying a gate voltage, and the HC increases or decreases with increasing positive or negative gate voltages. Thus, the effective regulation of HC is essential to improving the performance of advanced spintronic devices (e.g., MRAM and magnetic sensors). Our work will provide ideas for spin controlling and device application of 2D-FM/AFM heterostructures.

16.
J Interpers Violence ; : 8862605241275991, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39189048

RESUMEN

Previous studies have found that adolescent cyberbullying victimization is associated with cyberbullying perpetration and have explored the potential mediating mechanisms between the two. Although some valuable research has been accumulated, further exploration is needed on the underlying mechanisms of why cyber victims are transformed into cyberbullying perpetrators. Based on the General Aggression Model of Cyberbullying and the Social Role Theory, this study examined the mediating role of psychological entitlement and the moderating role of gender on the relationship between cyberbullying victimization and cyberbullying perpetration. A questionnaire survey was conducted on 836 adolescents, utilizing the cyberbullying victimization scale, cyberbullying perpetration scale, and psychological entitlement questionnaire. The results found that (a) cyberbullying victimization, psychological entitlement, and cyberbullying perpetration were significantly and positively correlated with each other; (b) after controlling for gender and age, cyberbullying victimization significantly and positively predicted cyberbullying perpetration and psychological entitlement mediated the relationship between cyberbullying victimization and cyberbullying perpetration; (c) Gender moderates the relationship between cyberbullying victimization and cyberbullying perpetration. Specifically, compared with the girls, cyberbullying victimization had a greater effect on cyberbullying perpetration among boys. The results of this study suggest that cyberbullying victims consider that they have more entitlement to bully others online. These findings support the General Aggression Model of Cyberbullying and provide new insights for the prevention and intervention of cyberbullying perpetration.

17.
Heliyon ; 10(15): e34889, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39157356

RESUMEN

The adhesion of bacteria to the surface leads to formation of biofilms causing numerous infection problems in implanting medical devices or interventional therapy. Traditional treatment for such problems is generally to administrate patients with antibiotics or antifungal agent. Alternatively, devices are taken out of the body to mechanically destroy the biofilm and re-used by surgery. In this study, a straightforward method was developed to remove biofilms using a MXene-based photothermal hydrogel. The hydrogel consists of dynamic crosslinking network formed by Schiff-base reaction between aldehyde-containing xyloglucan (OXG) and amine-containing MXene (NH2-MXene), which showed efficient killing of both gram-positive Staphylococcus aureus (S. aureus) and gram-negative Escherichia coli (E. coli) bacteria upon near-infrared (NIR) laser irradiation. The NH2-MXene/OXG nanocomposite hydrogel showed a high photothermal antibacterial efficiency and stable photothermal conversion, demonstrated by efficient removal of biofilms ex vivo.

18.
Front Public Health ; 12: 1422505, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39157526

RESUMEN

Air pollution has long been a significant environmental health issue. Previous studies have employed diverse methodologies to investigate the impacts of air pollution on public health, yet few have thoroughly examined its spatiotemporal heterogeneity. Based on this, this study investigated the spatiotemporal heterogeneity of the impacts of air pollution on public health in 31 provinces in China from 2013 to 2020 based on the theoretical framework of multifactorial health decision-making and combined with the spatial durbin model and the geographically and temporally weighted regression model. The findings indicate that: (1) Air pollution and public health as measured by the incidence of respiratory diseases (IRD) in China exhibit significant spatial positive correlation and local spatial aggregation. (2) Air pollution demonstrates noteworthy spatial spillover effects. After controlling for economic development and living environment factors, including disposable income, population density, and urbanization rate, the direct and indirect spatial impacts of air pollution on IRD are measured at 3.552 and 2.848, correspondingly. (3) China's IRD is primarily influenced by various factors such as air pollution, economic development, living conditions, and healthcare, and the degree of its influence demonstrates an uneven spatiotemporal distribution trend. The findings of this study hold considerable practical significance for mitigating air pollution and safeguarding public health.


Asunto(s)
Contaminación del Aire , Salud Pública , Análisis Espacio-Temporal , China/epidemiología , Contaminación del Aire/efectos adversos , Humanos , Ciudades , Enfermedades Respiratorias/epidemiología , Enfermedades Respiratorias/etiología , Exposición a Riesgos Ambientales/efectos adversos , Exposición a Riesgos Ambientales/estadística & datos numéricos
19.
PLoS One ; 19(8): e0307286, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39178246

RESUMEN

Ginsenoside Compound K (GCK) is the main metabolite of natural protopanaxadiol ginsenosides with diverse pharmacological effects. Gut microbiota contributes to the biotransformation of GCK, while the effect of gut microbiota on the pharmacokinetics of GCK in vivo remains unclear. To illustrate the role of gut microbiota in GCK metabolism in vivo, a systematic investigation of the pharmacokinetics of GCK in specific pathogen free (SPF) and pseudo-germ-free (pseudo-GF) rats were conducted. Pseudo-GF rats were treated with non-absorbable antibiotics. Liquid chromatography tandem mass spectrometry (LC-MS/MS) was validated for the quantification of GCK in rat plasma. Compared with SPF rats, the plasma concentration of GCK significantly increased after the gut microbiota depleted. The results showed that GCK absorption slowed down, Tmax delayed by 3.5 h, AUC0-11 increased by 1.3 times, CLz/F decreased by 0.6 times in pseudo-GF rats, and Cmax was 1.6 times higher than that of normal rats. The data indicated that gut microbiota played an important role in the pharmacokinetics of GCK in vivo.


Asunto(s)
Microbioma Gastrointestinal , Ginsenósidos , Ginsenósidos/farmacocinética , Animales , Microbioma Gastrointestinal/efectos de los fármacos , Ratas , Masculino , Espectrometría de Masas en Tándem , Ratas Sprague-Dawley , Cromatografía Liquida , Organismos Libres de Patógenos Específicos
20.
ACS Omega ; 9(31): 33959-33971, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39130569

RESUMEN

Indium phosphide (InP) single crystals, as key III-V compound semiconductor materials, play an irreplaceable role in various fields, such as optical communication and microwave millimeter-wave communication. Vertical gradient freeze (VGF) has become one of the main methods for industrial production of InP single crystals due to its advantages in temperature gradient control. However, defects such as twins and dislocations are easily generated during the production of InP single crystals by the VGF method. Through an in-depth study of the thermal field during the growth of InP single crystals, it is found that the cooling rate of the thermal field during single crystal growth is crucial and is closely related to the generation of twins, dislocations, and polycrystallization defects. Therefore, constructing a cooling model based on temperature control and the quality of InP single crystals has a positive driving effect on improving the yield of single crystal products. In this paper, by establishing a thermal field model of an InP single crystal furnace produced by the VGF method, the characteristics of temperature variation are analyzed in depth. Subsequently, numerical analysis of discrete cooling data during the cooling crystallization process is conducted, considering the quality of the InP single crystal growth. Combined with the spline regression algorithm, the optimal cooling model is fitted. Through positive and reverse experiment verification, the model shows significant effects in controlling internal stress in the crystal and reducing defect generation. Based on this model, we have successfully achieved effective suppression of defects, such as twins and dislocations, thereby significantly improving the quality of InP single crystals. This research not only provides a solid theoretical basis for the production of InP single crystals but also provides strong support for experimental applications.

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