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1.
J Obstet Gynaecol Can ; 46(6): 102456, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38588946

RESUMO

OBJECTIVES: Venous thromboembolism (VTE) occurs in 0.4%-0.7% of benign hysterectomies. Pelvic vascular compression secondary to fibroids may elevate VTE risk. We aimed to evaluate the incidence and timing of VTE among individuals undergoing hysterectomy for fibroids and other benign indications. METHODS: Retrospective cohort study of patients who underwent a hysterectomy for fibroid and non-fibroid indications from January 2015 to December 2021. Main outcome measure was VTE consisting of pulmonary embolism or deep venous thrombosis diagnosed during 3 periods: (1) preoperative (1 year before surgery until day before surgery), (2) early postoperative (surgery date through 6 weeks after surgery), and (3) late postoperative (6 weeks to 1 year after surgery). Demographics, comorbidities, surgical characteristics, and VTE rates were compared by indication. RESULTS: A total of 263 844 individuals with fibroids and 203 183 without were identified. In total, 1.1% experienced VTE. On multivariable regression (adjusted demographic confounders and route of surgery), the presence of fibroids was associated with increased odds of preoperative (adjusted odds ratio [aOR] 1.12; 95% CI 1.03-1.22, P = 0.011) and reduced odds of late postoperative VTE (aOR 0.81; 95% CI 0.73-0.91, P < 0.001). For individuals with fibroids, uterine weight ≥250 g and undergoing laparotomy were independently associated with preoperative (aOR 1.29; 95% CI 1.09-1.52, P = 0.003 and aOR 2.32; 95% CI 2.10-2.56, P < 0.001) and early postoperative VTE (aOR 1.32; 95% CI 1.08-1.62, P = 0.006 and aOR 1.72; 95% CI 1.50-1.96, P < 0.001). CONCLUSIONS: Patients with fibroids were at increased odds of having VTE 1 year before hysterectomy. For those with fibroids, elevated uterine weight and laparotomy were associated with greater risk of preoperative and early postoperative VTEs.

2.
Angew Chem Int Ed Engl ; : e202403463, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38661020

RESUMO

Metal sulfide (MS) is regarded as a promising candidate of the anode materials for sodium-ion battery (SIB) with ideal capacity and low cost, yet still suffers from the inferior cycling stability and voltage degradation. Herein, the coordination relationship between the discharge product Na2S with the Na+ (NaPF6) in the electrolyte, is revealed as the root cause for the cycling failure of MS. Na+-coordination effect assistants the dissolution of Na2S, further delocalizing Na2S from the reaction interface under the function of electric field, which leads to the solo oxidation of the discharge product element metal without the participation of Na2S. Besides, the higher highest occupied molecular orbital of Na2S suggest the facilitated Na2S solo oxidation to produce sodium polysulfides (NaPSs). Based on these, lowering the Na+ concentration of the electrolyte is proposed as a potential improvement strategy to change the coordination environment of Na2S, suppressing the side reactions of the solo-oxidation of element metal and Na2S. Consequently, the enhanced conversion reaction reversibility and prolonged cycle life are achieved. This work renders in-depth perception of failure mechanism and inspiration for realizing advanced conversion-type anode.

3.
Contraception ; : 110471, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38648922

RESUMO

OBJECTIVE: Immediately following the Dobbs decision, Ohio prohibited abortion after detection of fetal cardiac activity. We aimed to characterize changes in uptake of long-acting reversible contraception (LARC) and permanent contraception following the abrupt enactment of restrictive abortion legislation. STUDY DESIGN: We conducted a retrospective cohort study using electronic medical record (EMR) data of patients aged 15-55 who underwent permanent contraception (tubal ligation, vasectomy) or LARC placement (intrauterine device (IUD), contraceptive implant) at a multi-hospital system in northeast Ohio from 1/1/2022 to 12/31/2022; six months before and after Dobbs. We compared procedure volumes and patient characteristics. RESULTS: We identified 4247 tubal ligation and LARC procedures Pre-Dobbs, including 725 (17.1%) permanent contraception and 3522 (82.9%) LARC. Post-Dobbs, the total number of tubal ligation and LARC procedures increased by 15.8% (4916) and there was a significant increase in the proportion of permanent contraception, representing 20.1% of tubal ligation and LARC procedures (p<0.001). Vasectomy volume increased by 33.3% post-Dobbs, from 1193 to 1590 procedures. Compared to pre-Dobbs, patients undergoing contraceptive procedures post-Dobbs were younger (tubal ligation and LARC, 30.9 median years [24.5, 36.8] vs. 31.5 [25.2, 36.9], p=0.011); vasectomy, median 36.6 years [32.9, 39.6] vs. 37.2 [34.2, 40.4], p<0.001) and more likely to report single relationship status (57.4% vs. 55.9% for tubal ligation and LARC, p=0.028, and 23.0% vs. 18.1% for vasectomy, p=0.002). CONCLUSION: This study demonstrates increased uptake of contraceptive procedures following the Dobbs decision. This rise in permanent contraception suggests a relationship between abortion policy and contraceptive decision-making, especially among younger patients. IMPLICATIONS: Increased permanent and long-acting reversible contraception procedures following Dobbs reveal shifting contraceptive choices, particularly among younger individuals, indicating a connection between abortion policy and reproductive decisions.

4.
iScience ; 27(4): 109476, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38617565

RESUMO

Glacier-fed waters create strong environmental filtering for biota, whereby different organisms may assume distinct distribution patterns. By using environmental DNA-based metabarcoding, we investigated the multi-group biodiversity distribution patterns of the Parlung No. 4 Glacier, on the Tibetan Plateau. Altogether, 642 taxa were identified from the meltwater stream and the downstream Ranwu Lake, including 125 cyanobacteria, 316 diatom, 183 invertebrate, and 18 vertebrate taxa. As the distance increased from the glacier terminus, community complexity increased via sequential occurrences of cyanobacteria, diatoms, invertebrates, and vertebrates, as well as increasing taxa numbers. The stream and lake showed different community compositions and distinct taxa. Furthermore, the correlations with environmental factors and community assembly mechanisms showed group- and habitat-specific patterns. Our results reveal the rapid spatial succession and increasing community complexity along glacial flowpaths and highlight the varying adaptivity of different organisms, while also providing insight into the ecosystem responses to global change.

5.
Angew Chem Int Ed Engl ; : e202403399, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38483103

RESUMO

The conventional conductive three-dimensional (3D) host fails to effectively stabilize lithium metal anodes (LMAs) due to the internal incongruity arising from nonuniform lithium-ion gradient and uniform electric fields. This results in undesirable Li "top-growth" behavior and dendritic Li growth, significantly impeding the practical application of LMAs. Herein, we construct a 3D hierarchical host with gradient-distributed dielectric properties (GDD-CH) that effectively regulate Li-ion diffusion and deposition behavior. It comprises a 3D carbon fiber host modified by layer-by-layer bottom-up attenuating Sb particles, which could promote Li-ion homogeneously distribution and reduce ion concentration gradient via unique gradient dielectric polarization. Sb transforms into superionic conductive Li3Sb alloy during cycling, facilitating Li-ion dredging and pumps towards the bottom, dominating a bottom-up deposition regime confirmed by COMSOL Multiphysics simulations and physicochemical characterizations. Consequently, a stable cycling performance of symmetrical cells over 2000 h under a high current density of 10 mA cm-2 is achieved. The GDD-CH-based lithium metal battery shows remarkable cycling stability and ultra-high energy density of 378 Wh kg-1 with a low N/P ratio (1.51). This strategy of dielectric gradient design broadens the perspective for regulating the Li deposition mechanism and paves the way for developing high-energy-density lithium metal anodes with long durability.

6.
Nat Commun ; 15(1): 2529, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38514612

RESUMO

Transcortical vessels (TCVs) provide effective communication between bone marrow vascular system and external circulation. Although osteocytes are in close contact with them, it is not clear whether osteocytes regulate the homeostasis of TCVs. Here, we show that osteocytes maintain the normal network of TCVs by transferring mitochondria to the endothelial cells of TCV. Partial ablation of osteocytes causes TCV regression. Inhibition of mitochondrial transfer by conditional knockout of Rhot1 in osteocytes also leads to regression of the TCV network. By contrast, acquisition of osteocyte mitochondria by endothelial cells efficiently restores endothelial dysfunction. Administration of osteocyte mitochondria resultes in acceleration of the angiogenesis and healing of the cortical bone defect. Our results provide new insights into osteocyte-TCV interactions and inspire the potential application of mitochondrial therapy for bone-related diseases.


Assuntos
60489 , Osteócitos , Osteócitos/metabolismo , Células Endoteliais , Osso e Ossos , Mitocôndrias
7.
Sci China Life Sci ; 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38512561

RESUMO

Environmental DNA (eDNA) monitoring, a rapidly advancing technique for assessing biodiversity and ecosystem health, offers a noninvasive approach for detecting and quantifying species from various environmental samples. In this review, a comprehensive overview of current eDNA collection and detection technologies is provided, emphasizing the necessity for standardization and automation in aquatic ecological monitoring. Furthermore, the intricacies of water bodies, from streams to the deep sea, and the associated challenges they pose for eDNA capture and analysis are explored. The paper delineates three primary eDNA survey methods, namely, bringing back water, bringing back filters, and bringing back data, each with specific advantages and constraints in terms of labor, transport, and data acquisition. Additionally, innovations in eDNA sampling equipment, including autonomous drones, subsurface samplers, and in-situ filtration devices, and their applications in monitoring diverse taxa are discussed. Moreover, recent advancements in species-specific detection and eDNA metabarcoding are addressed, highlighting the integration of novel techniques such as CRISPR-Cas and nanopore sequencing that enable precise and rapid detection of biodiversity. The implications of environmental RNA and epigenetic modifications are considered for future applications in providing nuanced ecological data. Lastly, the review stresses the critical role of standardization and automation in enhancing data consistency and comparability for robust long-term biomonitoring. We propose that the amalgamation of these technologies represents a paradigm shift in ecological monitoring, aligning with the urgent call for biodiversity conservation and sustainable management of aquatic ecosystems.

8.
Artigo em Inglês | MEDLINE | ID: mdl-38517279

RESUMO

IMPORTANCE: Connective tissue disorders are proposed in the literature to be predisposing risk factors for pelvic floor disorders. Prior data characterizing the prevalence of and symptom burden related to pelvic floor disorders are limited for individuals with Marfan syndrome and are nonexistent for those with Loeys-Dietz syndrome. OBJECTIVE: The objective of this study was to determine the prevalence and severity of symptoms related to pelvic floor disorders among individuals with Marfan syndrome and Loeys-Dietz syndrome using the Pelvic Floor Distress Inventory-20 (PFDI-20). STUDY DESIGN: In this cross-sectional study, a survey including the PFDI-20 was administered to biologically female individuals older than 18 years with a confirmed diagnosis of Marfan syndrome or Loeys-Dietz Syndrome. Respondents were solicited through the websites, email lists, and social media forums of The Marfan Foundation and The Loeys-Dietz syndrome Foundation. RESULTS: A total of 286 respondents were included in the final analysis, 213 with Marfan syndrome and 73 with Loeys-Dietz syndrome. The median PFDI-20 score of the cohort was 43.8. Individuals with Loeys-Dietz syndrome had higher PFDI-20 scores and were more likely to have established risk factors for pelvic floor disorders that correlated with their PFDI-20 scores compared with those with Marfan syndrome. CONCLUSIONS: Respondents with Marfan syndrome and Loeys-Dietz syndrome experience a high burden of symptoms related to pelvic floor disorders. Despite the similar pathophysiology and clinical manifestations of these disorders, there were differences in PFDI-20 responses that may suggest that these diseases differ in the ways they affect the pelvic floor.

9.
Gynecol Oncol ; 185: 143-147, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38417209

RESUMO

BACKGROUND: We sought to create a laparoscopic-based model to predict the ability to perform a minimally invasive (MIS) cytoreductive surgery in advanced epithelial ovarian cancer patients who have received neoadjuvant chemotherapy (NACT). METHODS: Fifty women were enrolled in a multi-institutional prospective pilot study (NCT03378128). Each patient underwent laparoscopic evaluation of 43 abdominopelvic sites followed by surgeon dictated surgical approach, either continue MIS or laparotomically. However, if the procedure continued MIS, the placement of a hand-assist port for manual palpation was mandated to emulate a laparotomic approach and all 43 sites were re-evaluated. Sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy were calculated for each site to predict MIS resectability. Each parameter was assigned a numeric value based on the strength of statistical association and a total predictive index score (PIV) was assigned for each patient. Receiver operating characteristic curve analysis was used to assess the ability of the model to predict the MIS approach. RESULTS: Twenty-seven patients (61%) underwent MIS surgery. The following abdominopelvic sites were selected for inclusion in the model: gastrosplenic ligament, rectum, left mesocolon, transverse colon, right colon, cecum, appendix, liver capsule, intrahepatic fossa/gallbladder, ileum/jejunum. Using the PIV, a ROC was generated with an AUC = 0.695. In the final model, a PIV <2 identified patients able to undergo an optimal MIS cytoreductive surgery with an accuracy of 68.2%. The specificity, or the ability to identify patients who would not be able to undergo an optimal MIS interval cytoreductive surgery, was 66.7%. CONCLUSION: This predictive index model may help to guide future inclusion criteria in randomized studies evaluating the MIS approach in advanced epithelial ovarian cancer.

10.
Int Urogynecol J ; 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38416154

RESUMO

INTRODUCTION AND HYPOTHESIS: Combined surgical procedures with sacrocolpopexy (SCP) and rectopexy (RP) are more commonly being performed for treatment of multicompartment pelvic organ prolapse. This study aimed to compare healthcare resource utilization (HRU) within 6 weeks following combined surgery (SCP-RP) versus SCP alone (SCP-only). We hypothesized that concomitant RP does not impact HRU. METHODS: A retrospective cohort study of patients who underwent minimally invasive SCP from 2017 to 2022 was conducted at a tertiary referral center. Patients were grouped based on the performance of concomitant RP. HRU was defined as a composite of unscheduled office visits, emergency department visits, and readmissions before the 6-week postoperative visit. HRU was compared in the SCP-RP and SCP-only groups. Multivariable regression analysis was performed to identify factors associated with HRU. RESULTS: There were 144 patients in the SCP-RP group and 405 patients in the SCP-only group. Patient characteristics were similar between the two groups, with the following exceptions: the SCP-RP group was older, more likely to have comorbid conditions, and live >60 miles from the hospital. Of the 549 patients, 183 (33.3%) had ≥1 HRU encounter within 6 weeks after surgery. However, there was no difference between the SCP-RP and SCP-only groups in composite HRU (34.0% vs 33.1%, p = 0.84). The most common reasons for HRU were pain, urinary tract infection symptoms, and wound issues. Concomitant mid-urethral sling was associated with a two-fold increased risk of HRU after surgery. CONCLUSIONS: One in 3 patients undergoing minimally invasive SCP had at least one unanticipated encounter within 6 weeks after surgery. Concomitant RP was not associated with increased postoperative HRU.

12.
Artigo em Inglês | MEDLINE | ID: mdl-38212891

RESUMO

IMPORTANCE: Data on stress urinary incontinence (SUI) after minimally invasive sacrocolpopexy (SCP) with or without midurethral sling placement are limited. OBJECTIVE: The aim of the study was to determine the incidence of SUI after minimally invasive sacrocolpopexy. STUDY DESIGN: This was a secondary analysis of 2 randomized clinical trials of participants undergoing SCP. Participants completed symptom assessment and urodynamic testing. Participants underwent SCP with or without midurethral sling placement. Preoperatively, participants were defined as having symptomatic SUI, occult SUI, or no SUI. Participants completed the Pelvic Floor Distress Inventory-20 at 6 and 12 months postoperatively and were categorized as having persistent SUI in the setting of symptomatic or occult SUI or de novo SUI. RESULTS: Eighty-one participants were included. Sixty-one participants met inclusion criteria for the persistent SUI analysis: 42 participants with symptomatic SUI and 19 participants with occult SUI. There were 20 participants in the de novo SUI group. The overall incidence of persistent SUI was 26.2% (95% confidence interval [CI], 15.8%-39.1%) with 33.3% (95% CI, 19.6%-49.6%) of symptomatic and 10.5% (95% CI, 1.5%-33.1%) of occult participants. Bothersome symptoms were defined as "moderately" or "quite a bit" bothered postoperatively. Of participants with symptomatic SUI, 14.3% participants were bothered and no participants underwent retreatment. No patient with occult SUI was bothered; however, 1 patient underwent retreatment. The incidence of de novo SUI was 45% (95% CI, 23.1%-68.5%). No patient in the de novo SUI group was bothered or underwent SUI treatment. CONCLUSIONS: Approximately 1 in 4 participants reported persistent SUI. Almost 50% reported de novo SUI. However, few participants were bothered or underwent treatment.

13.
Chin J Integr Med ; 2024 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-38216838

RESUMO

OBJECTIVE: To explore the regulatory effect of Pien Tze Huang (PZH) on targeting partner of NOB1 (PNO1) and it's down-stream mediators in colorectal cancer (CRC) cells. METHODS: Quantitative polymerase chain reaction was performed to determine mRNA levels of PNO1, TP53, and CDKN1A. Western blotting was performed to determine protein levels of PNO1, p53, and p21. HCT-8 cells were transduced with a lentivirus over-expressing PNO1. Colony formation assay was used to detect cell survival in PNO1 overexpression of HCT-8 cells after PZH treatment. Cell-cycle distribution, cell viability and cell apoptosis were performed to identify the effect of PNO1 overexpression on cell proliferation and apoptosis of HCT-8 cells after PZH treatment. Xenograft BALB/c nude mice bearing HCT116 cells transduced with sh-PNO1 or sh-Ctrl lentivirus were evaluated. Western blot assay was performed to detect PNO1, p53, p21 and PCNA expression in tumor sections. Terminal deoxynucleotidyl transferase dUTP nick end labling (TUNEL) assay was used to determine the apoptotic cells in tissues. RESULTS: PZH treatment decreased cell viability, down-regulated PNO1 expression, and up-regulated p53 and p21 expressions in HCT-8 cells (P<0.05). PNO1 overexpression attenuated the effects of PZH treatment, including the expression of p53 and p21, cell growth, cell viability, cell cycle arrest and cell apoptosis in vitro (P<0.05). PNO1 knockdown eliminated the effects of PZH treatment on tumor growth, inhibiting cell proliferation inhibition and apoptosis induction in vivo (P<0.05). Similarly, PNO1 knockdown attenuated the effects of PZH treatment on the down-regulation of PNO1 and up-regulation of p53 and p21 in vivo (P<0.05). CONCLUSION: The mechanism by which PZH induces its CRC anti-proliferative effect is at least in part by regulating the expression of PNO1 and its downstream targets p53 and p21.

14.
Small ; 20(5): e2306428, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37759404

RESUMO

Silicon (Si) is considered a promising commercial material for the next-generation of high-energy density lithium-ion battery (LIB) due to its high theoretical capacity. However, the severe volume changes and the poor conductivity hinder the practical application of Si anode. Herein, a novel core-shell heterostructure, Si as the core and V3 O4 @C as the shell (Si@V3 O4 @C), is proposed by a facile solvothermal reaction. Theoretical simulations have shown that the in-situ-formed V3 O4 layer facilitates the rapid Li+ diffusion and lowers the energy barrier of Li transport from the carbon shell to the inner core. The 3D network structure constructed by amorphous carbon can effectively improve electronic conductivity and structural stability. Benefiting from the rationally designed structure, the optimized Si@V3 O4 @C electrode exhibits an excellent cycling stability of 1061.1 mAh g-1 at 0.5 A g-1 over 700 cycles (capacity retention of 70.0%) with an average Coulombic efficiency of 99.3%. In addition, the Si@V3 O4 @C||LiFePO4 full cell shows a superior capacity retention of 78.7% after 130 cycles at 0.5 C. This study opens a novel way for designing high-performance silicon anode for advanced LIBs.

15.
Chin J Traumatol ; 27(1): 1-10, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38065706

RESUMO

Programmed cell death 1 ligand 1 (PD-L1) is an important immunosuppressive molecule, which inhibits the function of T cells and other immune cells by binding to the receptor programmed cell death-1. The PD-L1 expression disorder plays an important role in the occurrence, development, and treatment of sepsis or other inflammatory diseases, and has become an important target for the treatment of these diseases. Mesenchymal stem cells (MSCs) are a kind of pluripotent stem cells with multiple differentiation potential. In recent years, MSCs have been found to have a strong immunosuppressive ability and are used to treat various inflammatory insults caused by hyperimmune diseases. Moreover, PD-L1 is deeply involved in the immunosuppressive events of MSCs and plays an important role in the treatment of various diseases. In this review, we will summarize the main regulatory mechanism of PD-L1 expression, and discuss various biological functions of PD-L1 in the immune regulation of MSCs.


Assuntos
Antígeno B7-H1 , Imunomodulação , Células-Tronco Mesenquimais , Humanos , Antígeno B7-H1/metabolismo , Células-Tronco Mesenquimais/imunologia , Linfócitos T/metabolismo
16.
FASEB J ; 38(1): e23354, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38085162

RESUMO

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common malignancy worldwide, and the development of novel therapeutic strategies for HNSCC requires a profound understanding of tumor cells and the tumor microenvironment (TME). Additionally, HNSCC has a poor prognosis, necessitating the use of genetic markers for predicting clinical outcomes in HNSCC. In this study, we performed single-cell sequencing analysis on tumor tissues from seven HNSCC patients, along with one adjacent normal tissue. Firstly, the analysis of epithelial cell clusters revealed two clusters of malignant epithelial cells, characterized by unique gene expression patterns and dysregulated signaling pathways compared to normal epithelial cells. Secondly, the examination of the TME unveiled extensive crosstalk between fibroblasts and malignant epithelial cells, potentially mediated through ligand-receptor interactions such as COL1A1-SDC1, COL1A1-CD44, and COL1A2-SDC1. Furthermore, transcriptional heterogeneity was observed in immune cells present in the TME, including macrophages and dendritic cells. Finally, leveraging the gene expression profiles of malignant epithelial cells, we developed a prognostic model comprising six genes, which we validated using two independent datasets. These findings shed light on the heterogeneity within HNSCC tumors and the intricate interplay between malignant cells and the TME. Importantly, the developed prognostic model demonstrates high efficacy in predicting the survival outcomes of HNSCC patients.


Assuntos
Carcinoma , Neoplasias de Cabeça e Pescoço , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Prognóstico , Neoplasias de Cabeça e Pescoço/genética , Células Epiteliais , Microambiente Tumoral/genética
17.
Chemosphere ; 346: 140521, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37925028

RESUMO

The traditional method of preparing graphene will cause serious environmental pollution, and the combustion of polymer materials will seriously harm people's health. In this paper, a Cu-MOF-coated graphene composite flame retardant (G@Cu-MOF) rich in flame retardant elements such as B and N was synthesized through green mechanical ball milling method. Flame retardants reduce the threat to the environment and people's lives and property. After adding 6 wt% G@Cu-MOF, the peak heat release rate, total heat release rate, CO production and CO2 production of epoxy resin (EP) composite samples decreased by 55, 14, 59, and 55%, respectively. This type of Cu-MOF releases incombustible gases such as boron trifluoride (BF3) and ammonia (NH3) during combustion, diluting the concentration of combustible gases and producing copper borate in the condensed phase. Cu2+ is reduced to Cu, and boron compounds are converted into boron oxides. The thermal conductivity of graphene can reduce the temperature of the matrix, and has good flame retardancy. It synergistically acts with Cu-MOF to promote the formation of high-quality residual char, and can significantly inhibit the heat and smoke release of EP. It plays a role in flame retardancy and protecting the substrate from fire. This study provides a new approach for preparing graphene hybrid flame retardants through mechanical ball milling, in order to improve the flame retardancy of EP and suppress the release of smoke and toxic gases.


Assuntos
Retardadores de Chama , Grafite , Humanos , Fumaça , Cobre , Gases
18.
Behav Brain Res ; 459: 114811, 2024 02 29.
Artigo em Inglês | MEDLINE | ID: mdl-38103871

RESUMO

Parkinson's disease (PD) is a neurodegenerative disease characterized by progressive loss of dopaminergic (DA) neurons in the substantia nigra pars compacta (SNc) and the presence of Lewy bodies (LBs) or Lewy neurites (LNs) which consist of α-synuclein (α-syn) and a complex mix of other biomolecules. Mitochondrial dysfunction is widely believed to play an essential role in the pathogenesis of PD and other related neurodegenerative diseases. But mitochondrial dysfunction is subject to complex genetic regulation. There is increasing evidence that PD-related genes directly or indirectly affect mitochondrial integrity. Therefore, targeted regulation of mitochondrial function has great clinical application prospects in the treatment of PD. However, lots of PD drugs targeting mitochondria have been developed but their clinical therapeutic effects are not ideal. This review aims to reveal the role of mitochondrial dysfunction in the pathogenesis of neurodegenerative diseases based on the mitochondrial structure and function, which may highlight potential interventions and therapeutic targets for the development of PD drugs to recover mitochondrial dysfunction in neurodegenerative diseases.


Assuntos
Doenças Mitocondriais , Doenças Neurodegenerativas , Doença de Parkinson , Humanos , Doença de Parkinson/patologia , Doenças Neurodegenerativas/metabolismo , alfa-Sinucleína/metabolismo , Parte Compacta da Substância Negra/metabolismo , Mitocôndrias/metabolismo , Neurônios Dopaminérgicos/metabolismo
19.
Zhongguo Zhong Yao Za Zhi ; 48(22): 5977-5984, 2023 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-38114203

RESUMO

Plant-derived exosome-like nanoparticles(PELNs) are a class of membranous vesicles with diameters approximately ranging from 30 to 300 nm, isolated from plant tissues. They contain components such as proteins, lipids, and nucleic acids. PELNs play an important role in the metabolism of plant substances and immune defense, and can also cross-regulate the physiological activities of fungi and animal cells, showing significant potential applications. In recent years, research on PELNs has significantly increased, highlighting three main issues:(1) the mixed sources of plant materials for PELNs;(2) the lack of a unified system for isolating and characterizing PELNs;(3) the urgent need to elucidate the molecular mechanisms underlying the cross-regulation of biological functions by PELNs. This article focused on these concerns. It began by summarizing the biological origin and composition of PELNs, discussing the techniques for isolating and characterizing PELNs, and analyzing their biomedical applications and potential future research directions., aiming to promote the establishment of standardized research protocols for PELNs and provide theoretical references for in-depth exploration of the mechanisms underlying PELNs' cross-regulatory effects.


Assuntos
Exossomos , Nanopartículas , Ácidos Nucleicos , Animais , Exossomos/metabolismo , Proteínas/metabolismo , Plantas/metabolismo
20.
Small ; : e2308910, 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38150628

RESUMO

The efficient removal of radioactive uranium from aqueous solution is of great significance for the safe and sustainable development of nuclear power. An ultrathin 2D metal-organic framework (MOF) nanosheet with cavity structures was elaborately fabricated based on a calix[4]arene ligand. Incorporating the permanent cavity structures on MOF nanosheet can fully utilize its structural characteristics of largely exposed surface area and accessible adsorption sites in pollutant removal, achieving ultrafast adsorption kinetics, and the functionalized cavity structure would endow the MOF nanosheets with the ability to achieve preconcentration and extraction of uranium from aqueous solution, affording ultrahigh removal efficiency even in ultra-low concentrations. Thus, more than 97% uranium can be removed from the concentration range of 50-500 µg L-1 within 5 min. Moreover, the 2D nano-material exhibits ultra-high anti-interference ability, which can efficiently remove uranium from groundwater and seawater. The adsorption mechanism was investigated by X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FT-IR) analysis, and density functional theory (DFT) calculations, which revealed that the cavity structure plays an important role in uranium capture. This study not only realizes highly efficient uranium removal from aqueous solution but also opens the door to achieving ultrathin MOF nanosheets with cavity structures, which will greatly expand the applications of MOF nanosheets.

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