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1.
Mol Aspects Med ; 97: 101270, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38583268

RESUMO

The onset of sarcopenia is intimately linked with aging, posing significant implications not only for individual patient quality of life but also for the broader societal healthcare framework. Early and accurate identification of sarcopenia and a comprehensive understanding of its mechanistic underpinnings and therapeutic targets paramount to addressing this condition effectively. This review endeavors to present a cohesive overview of recent advancements in sarcopenia research and diagnosis. We initially delve into the contemporary diagnostic criteria, specifically referencing the European Working Group on Sarcopenia in Older People (EWGSOP) 2 and Asian Working Group on Sarcopenia (AWGS) 2019 benchmarks. Additionally, we elucidate comprehensive assessment techniques for muscle strength, quantity, and physical performance, highlighting tools such as grip strength, chair stand test, dual-energy X-ray Absorptiometry (DEXA), bioelectrical impedance analysis (BIA), gait speed, and short physical performance battery (SPPB), while also discussing their inherent advantages and limitations. Such diagnostic advancements pave the way for early identification and unequivocal diagnosis of sarcopenia. Proceeding further, we provide a deep-dive into sarcopenia's pathogenesis, offering a thorough examination of associated signaling pathways like the Myostatin, AMP-activated protein kinase (AMPK), insulin/IGF-1 Signaling (IIS), and the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathways. Each pathway's role in sarcopenia mediation is detailed, underscoring potential therapeutic target avenues. From a mechanistic perspective, the review also underscores the pivotal role of mitochondrial dysfunction in sarcopenia, emphasizing elements such as mitochondrial oxidative overload, mitochondrial biogenesis, and mitophagy, and highlighting their therapeutic significance. At last, we capture recent strides made in sarcopenia treatment, ranging from nutritional and exercise interventions to potential pharmacological and supplementation strategies. In sum, this review meticulously synthesizes the latest scientific developments in sarcopenia, aiming to enhance diagnostic precision in clinical practice and provide comprehensive insights into refined mechanistic targets and innovative therapeutic interventions, ultimately contributing to optimized patient care and advancements in the field.

2.
Comput Struct Biotechnol J ; 23: 491-505, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38249783
3.
Small ; : e2311180, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38174602

RESUMO

The practical application of the room-temperature sodium-sulfur (RT Na-S) batteries is currently limited by low reversible capacity and serious capacity decay due to the sluggish reaction kinetics and shuttle effect. It is necessary to design a suitable sulfur host integrated with electrocatalysts to realize effective chemisorption and catalysis of sodium polysulfides (NaPSs). Herein, under the guidance of theoretical calculation, the Mott-Schottky heterojunction with a built-in electric field composed of iron (Fe) and iron disulfide (FeS2 ) components anchored on a porous carbon matrix (Fe/FeS2 -PC) is designed and prepared. The enhanced chemisorption effect of Fe, the fast electrocatalytic effect of FeS2 , and the fast transfer effect of the built-in electric field within the Fe/FeS2 heterojunction in the cathode of RT Na-S batteries work together to effectively improve the electrochemical performance. As a result, the Fe/FeS2 -PC@S cathode exhibits high reversible capacity (815 mAh g-1 after 150 cycles at 0.2 A g-1 ) and excellent stability (516 mAh g-1 after 600 cycles at 5 A g-1 , with only 0.07% decay per cycle). The design of the Fe/FeS2 heterojunction electrocatalyst provides a new strategy for the development of highly stable RT Na-S batteries.

4.
Biomark Res ; 12(1): 5, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38191508

RESUMO

Neddylation is a post-translational modification process, similar to ubiquitination, that controls several biological processes. Notably, it is often aberrantly activated in neoplasms and plays a critical role in the intricate dynamics of the tumor microenvironment (TME). This regulatory influence of neddylation permeates extensively and profoundly within the TME, affecting the behavior of tumor cells, immune cells, angiogenesis, and the extracellular matrix. Usually, neddylation promotes tumor progression towards increased malignancy. In this review, we highlight the latest understanding of the intricate molecular mechanisms that target neddylation to modulate the TME by affecting various signaling pathways. There is emerging evidence that the targeted disruption of the neddylation modification process, specifically the inhibition of cullin-RING ligases (CRLs) functionality, presents a promising avenue for targeted therapy. MLN4924, a small-molecule inhibitor of the neddylation pathway, precisely targets the neural precursor cell-expressed developmentally downregulated protein 8 activating enzyme (NAE). In recent years, significant advancements have been made in the field of neddylation modification therapy, particularly the integration of MLN4924 with chemotherapy or targeted therapy. This combined approach has demonstrated notable success in the treatment of a variety of hematological and solid tumors. Here, we investigated the inhibitory effects of MLN4924 on neddylation and summarized the current therapeutic outcomes of MLN4924 against various tumors. In conclusion, this review provides a comprehensive, up-to-date, and thorough overview of neddylation modifications, and offers insight into the critical importance of this cellular process in tumorigenesis.

5.
Arch Gynecol Obstet ; 2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38280055

RESUMO

OBJECTIVE: This study aims to assess the feasibility and effectiveness of color doppler flow imaging (CDFI) technology and the Slow Flow HD imaging technique in identifying fetal pulmonary veins (PVs) in the first trimester (11-13 + 6 weeks), and further explore the factors affecting fetal pulmonary vein identification in early pregnancy. METHODS: Echocardiography and scanning of PVs were performed in 240 normal singleton fetuses in early pregnancy by using CDFI and slow flow HD techniques, to compare the ability of two methods to identify the PVs. Slow Flow HD technology was used to further investigate the difference of PVs identification at different gestational ages [group I (11-11 + 6 weeks), group II (12-12 + 6 weeks), group III (13-13 + 6 weeks)] and with different maternal body mass indices (BMI) (≥ 25 and < 25). In 31 cases of 240 fetuses, transvaginal ultrasonography was added due to maternal habitus or significant retroversion of the uterus, and the difference in PVs identification between transabdominal and transvaginal examination was analyzed. RESULTS: Successful PVs identification rates via CDFI and Slow Flow HD were 32.0% and 88.3%, respectively (p < 0.05). The identification rate of at least one and two pulmonary veins in Slow Flow HD was 88.3% and 76.2%, and all four pulmonary veins in 11.6% (p < 0.05). The identification rate of group I, II and III were 76.4%, 88.9% and 96.0%, respectively. The identification rate was 45.1% in the transabdominal ultrasound group and 83.8% in the transvaginal ultrasound group. The identification rate was 62.5% in the BMI ≥ 25 group and 94.7% in the BMI < 25 group (p < 0.05). CONCLUSIONS: Slow Flow HD can detect PVs in early pregnancy more often than using CDFI. Slow Flow HD is a feasible and effective imaging technique for evaluating PVs in early pregnancy.

6.
Small ; 20(2): e2304210, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37626458

RESUMO

Due to their high designability, unique geometric and electronic structures, and surface coordination chemistry, atomically precise metal nanoclusters are an emerging class of functional nanomaterials at the forefront of materials research. However, the current research on metal nanoclusters is mainly fundamental, and their practical applications are still uncharted. The surface binding properties and redox activity of Au24 Pt(PET)18 (PET: phenylethanethiolate, SCH2 CH2 Ph) nanoclusters are herein harnessed as an high-efficiency electrocatalyst for the anchoring and rapid conversion of lithium polysulfides in lithium-sulfur batteries (LSBs). Au24 Pt(PET)18 @G composites are prepared by using the large specific surface area, high porosity, and conductive network of graphene (G) for the construction of battery separator that can inhibit polysulfide shuttle and accelerate electrochemical kinetics. Resultantly, the LSB using a Au24 Pt(PET)18 @G-based separator presents a high reversible specific capacity of 1535.4 mA h g-1 for the first cycle at 0.2 A g-1 and a rate capability of 887 mA h g-1 at 5 A g-1 . After 1000 cycles at 5 A g-1 , the capacity is 558.5 mA h g-1 . This study is a significant step toward the application of metal nanoclusters as optimal electrocatalysts for LSBs and other sustainable energy storage systems.

7.
Clin. transl. oncol. (Print) ; 25(12): 3420-3430, dec. 2023.
Artigo em Inglês | IBECS | ID: ibc-227287

RESUMO

Background The lncRNA HOTAIR is frequently overexpressed in breast cancer tissues and plays an important role in the development of breast cancer. Here, we investigated the effect of the lncRNA HOTAIR on the biological behaviour of breast cancer cells and its molecular mechanism. Methods We investigated the level of HOTAIR in breast cancer and its clinical pathological characteristics by bioinformatic methods. Then, we evaluated the effects of HOTAIR and miRNA-1 expression on the biological behaviour of breast cancer cells by qPCR, Cell Counting Kit-8 (CCK-8) assay, clonogenic assays, Transwell assay and flow cytometry for cell proliferation, invasion migration and apoptosis, and cell cycle analysis. Finally, the target genes of the lncRNA HOTAIR/miR-1/GOLPH3 regulatory axis were validated by luciferase reports. Results The expression of HOTAIR in breast cancer tissues was significantly higher than that in normal breast tissues (P < 0.05). Silencing of HOTAIR suppressed cell proliferation, invasion and migration, promoted apoptosis and induced G1 phase block in breast cancer (P < 0.0001). We also verified that miR-1 is a target of HOTAIR and that GOLPH3 is a target of miR-1 by luciferase reporter assays (P < 0.001). Conclusions The expression of HOTAIR was significantly elevated in breast cancer tissues. Reducing the expression of HOTAIR inhibited the proliferation, invasion and migration of breast cancer cells and promoted apoptosis, and the mechanism was mainly the effect of the lncRNA HOTAIR/miR-1/GOLPH3 regulatory axis on the biological behaviour of breast cancer cells (AU)


Assuntos
Humanos , Feminino , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Apoptose/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Luciferases/metabolismo , Proteínas de Membrana/genética
9.
Pharmaceuticals (Basel) ; 16(10)2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37895855

RESUMO

This comprehensive review delves into the rapidly evolving arena of cancer vaccines. Initially, we examine the intricate constitution of the tumor microenvironment (TME), a dynamic factor that significantly influences tumor heterogeneity. Current research trends focusing on harnessing the TME for effective tumor vaccine treatments are also discussed. We then provide a detailed overview of the current state of research concerning tumor immunity and the mechanisms of tumor vaccines, describing the complex immunological processes involved. Furthermore, we conduct an exhaustive analysis of the contemporary research landscape of tumor vaccines, with a particular focus on peptide vaccines, DNA/RNA-based vaccines, viral-vector-based vaccines, dendritic-cell-based vaccines, and whole-cell-based vaccines. We analyze and summarize these categories of tumor vaccines, highlighting their individual advantages, limitations, and the factors influencing their effectiveness. In our survey of each category, we summarize commonly used tumor vaccines, aiming to provide readers with a more comprehensive understanding of the current state of tumor vaccine research. We then delve into an innovative strategy combining cancer vaccines with other therapies. By studying the effects of combining tumor vaccines with immune checkpoint inhibitors, radiotherapy, chemotherapy, targeted therapy, and oncolytic virotherapy, we establish that this approach can enhance overall treatment efficacy and offset the limitations of single-treatment approaches, offering patients more effective treatment options. Following this, we undertake a meticulous analysis of the entire process of personalized cancer vaccines, elucidating the intricate process from design, through research and production, to clinical application, thus helping readers gain a thorough understanding of its complexities. In conclusion, our exploration of tumor vaccines in this review aims to highlight their promising potential in cancer treatment. As research in this field continues to evolve, it undeniably holds immense promise for improving cancer patient outcomes.

10.
Clin Transl Med ; 13(8): e1346, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37525587

RESUMO

BACKGROUND: Breast cancer (BC) is a highly heterogeneous disease, and although immunotherapy has recently increased patient survival in a number of solid and hematologic malignancies, most BC subtypes respond poorly to immune checkpoint blockade therapy (ICB). B cells, particularly those that congregate in tertiary lymphoid structures (TLS), play a significant role in antitumour immunity. However, B-cell heterogeneity at single-cell resolution and its clinical significance with TLS in BC need to be explored further. METHODS: Primary tumour lesions and surrounding normal tissues were taken from 14 BC patients, totaling 124,587 cells, for single-cell transcriptome sequencing and bioinformatics analysis. RESULTS: Based on the usual markers, the single-cell transcriptome profiles were classified into various clusters. A thorough single-cell study was conducted with a focus on tumour-infiltrating B cells (TIL-B) and tumour-associated neutrophils (TAN). TIL-B was divided into five clusters, and unusual cell types, such as follicular B cells, which are strongly related to immunotherapy efficacy, were identified. In BC, TAN and TIL-B infiltration are positively correlated, and at the same time, compared with TLS-high, TAN and TIL-B in TLS-low group are significantly positively correlated. CONCLUSIONS: In conclusion, our study highlights the heterogeneity of B cells in BC, explains how B cells and TLS contribute significantly to antitumour immunity at both the single-cell and clinical level, and offers a straightforward marker for TLS called CD23. These results will offer more pertinent information on the applicability and effectiveness of tumour immunotherapy for BC.


Assuntos
Neoplasias da Mama , Estruturas Linfoides Terciárias , Humanos , Feminino , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Transcriptoma/genética , Estruturas Linfoides Terciárias/genética , Estruturas Linfoides Terciárias/metabolismo , Terapia Neoadjuvante , Linfócitos do Interstício Tumoral , Prognóstico
12.
Clin Transl Oncol ; 25(12): 3420-3430, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37099061

RESUMO

BACKGROUND: The lncRNA HOTAIR is frequently overexpressed in breast cancer tissues and plays an important role in the development of breast cancer. Here, we investigated the effect of the lncRNA HOTAIR on the biological behaviour of breast cancer cells and its molecular mechanism. METHODS: We investigated the level of HOTAIR in breast cancer and its clinical pathological characteristics by bioinformatic methods. Then, we evaluated the effects of HOTAIR and miRNA-1 expression on the biological behaviour of breast cancer cells by qPCR, Cell Counting Kit-8 (CCK-8) assay, clonogenic assays, Transwell assay and flow cytometry for cell proliferation, invasion migration and apoptosis, and cell cycle analysis. Finally, the target genes of the lncRNA HOTAIR/miR-1/GOLPH3 regulatory axis were validated by luciferase reports. RESULTS: The expression of HOTAIR in breast cancer tissues was significantly higher than that in normal breast tissues (P < 0.05). Silencing of HOTAIR suppressed cell proliferation, invasion and migration, promoted apoptosis and induced G1 phase block in breast cancer (P < 0.0001). We also verified that miR-1 is a target of HOTAIR and that GOLPH3 is a target of miR-1 by luciferase reporter assays (P < 0.001). CONCLUSIONS: The expression of HOTAIR was significantly elevated in breast cancer tissues. Reducing the expression of HOTAIR inhibited the proliferation, invasion and migration of breast cancer cells and promoted apoptosis, and the mechanism was mainly the effect of the lncRNA HOTAIR/miR-1/GOLPH3 regulatory axis on the biological behaviour of breast cancer cells.


Assuntos
Neoplasias da Mama , MicroRNAs , RNA Longo não Codificante , Humanos , Feminino , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , MicroRNAs/genética , MicroRNAs/metabolismo , Luciferases/metabolismo , Proliferação de Células/genética , Movimento Celular/genética , Apoptose/genética , Regulação Neoplásica da Expressão Gênica , Proteínas de Membrana/genética
13.
Cancer Cell Int ; 23(1): 22, 2023 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-36759846

RESUMO

BACKGROUND: Relevant studies suggest that serum vitamin level is related to the risk of breast cancer, and dietary pattern and drug supplementation can significantly affect the level of vitamin in the body. Therefore, intervention of vitamin level in the body is expected to be a potential strategy to reduce the risk of breast cancer. However, the current epidemiological findings of serum vitamin levels and breast cancer risk are inconsistent, and the relationship between serum vitamin and breast cancer is still controversial. In this study, we compared the serum vitamin expression levels of healthy people, benign breast patients, and breast cancer patients, and evaluated the relationship between B vitamin levels and breast cancer risk. METHODS: The study used liquid chromatography-tandem mass spectrometry to determine the serum vitamin levels of 520 people who attended Yunnan Cancer Hospital from September 2020 to December 2020. After screening by exclusion criteria, 38 patients with benign breast diseases, 87 patients with breast cancer and 91 healthy controls were finally included. The kruskal-wallis H test was used to compare the differences in serum vitamin levels of subjects. Χ2 test was used to evaluate the relationship between B vitamin level and age,BMI,TNM staging,Ki-67,Her-2,surgery and chemotherapy, and other baseline characteristics and through binary logistic regression analysis, calculating odds ratio and 95% confidence interval (CI) to evaluate the relationship between B vitamins and breast cancer risk. CONCLUSION: The levels of VitB1 and VitB5 in the serum of breast cancer patients and patients with benign breast diseases were higher than those in the healthy control group, while the expression levels of VitB3 in breast cancer patients were lower than those in the healthy control group and the breast benign disease groups. The level of VitB1 was positively correlated with breast cancer risk. The VitB3 level was negatively correlated with breast cancer risk. The VitB5 level is not significantly related to the risk of breast cancer.

14.
Small ; 19(16): e2206083, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36683234

RESUMO

The notorious shuttle effect and sluggish conversion of polysulfides seriously hinder the practical application of Lithium-sulfur (Li-S) batteries. In this study, a novel architecture of MoS2 /MoO3 heterostructure uniformly distributed on carbon nanotubes (MoS2 /MoO3 @CNT) is designed and introduced into Li-S batteries via decorating commercial separator to regulate the redox reactions of polysulfides. Systematic experiments and theoretical calculations showed that the heterostructure not only provides sufficient surface affinity to capture polysulfides and acts as an active catalyst to promote the conversion of polysulfides, but also the highly conductive CNT enables rapid electron/ion migration. As a result, Li-S batteries with the MoS2 /MoO3 @CNT-PP separator deliver an impressive reversible capacity (1015 mAh g-1 at 0.2 A g-1 after 100 cycles), excellent rate capacity (873 mAh g-1 at 5 A g-1 ), and low self-discharge capacity loss (94.6% capacity retention after 7 days of standing). Moreover, even at an elevated temperature of 70 °C, it still exhibits high-capacity retention (800 mAh g-1 at 1 A g-1 after 100 cycles). Encouragingly, when the sulfur load is increased to 8.7 mg cm-2 , the high reversible areal capacity of 6.61 mAh cm-2 can be stably maintained after 100 cycles, indicating a high potential for practical application.

15.
Front Oncol ; 12: 994296, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36387123

RESUMO

Backgrounds: Prostate cancer (PCa) is the second most common male cancer in the world and based on its high prevalence and overwhelming effect on patients, more precise diagnostic and therapeutic methods are essential research topics. As such, this study aims to evaluate the value of three-dimensional transrectal ultrasound (3D-TRUS) in the detection, diagnosis and biopsy of PCa, and to provide a basis for clinical practice of PCa. Methods: Retrospective analysis and comparison of a total of 401 male patients who underwent prostate TRUS in our hospital from 2019 to 2020 were conducted, with all patients having prostate biopsy. Nomogram was used to estimate the probability of different ultrasound signs in diagnosing prostate cancer. The ROC curve was used to estimate the screening and diagnosis rates of 3D-TRUS, MRI and TRUS for prostate cancer. Results: A total of 401 patients were randomly divided into two groups according to different methods of prostate ultrasonography, namely the TRUS group (251 patients) and the 3D-TRUS group (150 patients). Of these cases, 111 patients in 3D-TRUS group underwent MRI scan. The nomogram further determined the value of 3D-TRUS for prostate cancer. The ROC AUC of prostate cancer detected by TRUS, MRI and 3D-TRUS was 0.5580, 0.6216 and 0.6267 respectively. Biopsy complications were lower in 3D-TRUS group than TRUS group, which was statistically significant (P<0.005). Conclusions: The accuracy of 3D-TRUS was higher in diagnosis and biopsy of prostate cancer. Meanwhile, the positive rate of biopsy could be improved under direct visualization of 3D-TRUS, and the complications could be decreased markedly. Therefore, 3D-TRUS was of high clinical value in diagnosis and biopsy of prostate cancer.

16.
Sci Rep ; 12(1): 10395, 2022 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35729333

RESUMO

There are different characteristics of BC in developing countries and developed countries. We intended to study the factors which influence the survival and prognosis of BC between southern China and the United States. (a) To study the two groups BC patients in southern China from 2001 to 2016 and SEER database from 1975 to 2016. (b) To register, collect and analyze the clinicopathological features and treatment information. Our study found that there are significant differences in tumor size, positive lymph node status and KI-67 between southern China and SEER cohort (P < 0.000). The positive lymph node status may be one of the causes of difference of morbidity and mortality of BC patients in China. Furthermore, the differences in treatment methods may also account for the differences between China and seer databases.


Assuntos
Neoplasias da Mama , Neoplasias da Mama/patologia , Estudos de Coortes , Bases de Dados Factuais , Feminino , Humanos , Estadiamento de Neoplasias , Prognóstico , Programa de SEER , Estados Unidos/epidemiologia
17.
ACS Appl Mater Interfaces ; 14(9): 11739-11749, 2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-35200005

RESUMO

SnS2-based materials have attracted considerable attention in energy storage and conversion owing to their high lithium activity and theoretical capacity. However, the practical application is severely limited by the low coulombic efficiency and short cycle life due to irreversible side reactions, low conductivity, and serious pulverization in the discharge/charge process. In this study, sheet-like stacking SnS2/reduced graphene oxide (rGO) heterostructures were developed using a facile solvothermal method. It was found that the composites between SnS2 nanoplates and rGO nanosheets are closely coupled through van der Waals interactions, providing efficient electron/ion paths to ensure high electrical conductivity and sufficient buffer space to alleviate volume expansion. Therefore, the SnS2/rGO heterostructure anode can obtain a high capacity of 840 mA h g-1 after 120 cycles at a current density of 200 mA g-1 and maintain a capacity of 450 mA h g-1 after 1000 cycles at 1000 mA g-1. In situ X-ray diffraction tests showed that SnS2/rGO undergoes typical initial intercalation, conversion, and subsequent alloying reactions during the first discharge, and most of the reactions are dealloying/alloying in the subsequent cycles. The galvanostatic intermittent titration technique showed that the diffusion of lithium ions in the SnS2/rGO heterostructures is faster in the intercalation and conversion reactions than in the alloying reactions. These observations help to clarify the reaction mechanism and ion diffusion behavior in the SnS2 anode materials, thus providing valuable insights for improving the energy efficiency of lithium-ion batteries.

18.
ACS Appl Mater Interfaces ; 14(3): 4079-4090, 2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35005891

RESUMO

In the wake of shaping the energy future through materials innovation, lithium-sulfur batteries (LSBs) are top-of-the-line energy storage system attributed to their high theoretical energy density and specific capacity inclusive of low material costs. Despite their strengths, LSBs suffer from the cross-over of soluble polysulfide redox species to the anode, entailing fast capacity fading and inferior cycling stability. Adding to the concern, the insulating character of polysulfides lends to sluggish reaction kinetics. To address these challenges, we construct optimized polysulfide blockers-cum-conversion catalysts by accommodating the battery separator with covalent organic framework@Graphene (COF@G) composites. We settle on a crystalline TAPP-ETTB COF in the interest of its nitrogen-enriched scaffold with a regular pore geometry, providing ample lithiophilic sites for strong chemisorption and catalytic effect to polysulfides. On another front, graphene enables high electron mobility, boosting the sulfur redox kinetics. Consequently, a lithium-sulfur battery with a TAPP-ETTB COF@G-based separator demonstrates a high reversible capacity of 1489.8 mA h g-1 at 0.2 A g-1 after the first cycle and good cyclic performance (920 mA h g-1 after 400 cycles) together with excellent rate performance (827.7 mA h g-1 at 2 A g-1). The scope and opportunities to harness the designability and synthetic structural control in crystalline organic materials is a promising domain at the interface of sustainable materials, energy storage, and Li-S chemistry.

19.
Dalton Trans ; 50(41): 14884-14890, 2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34605518

RESUMO

2D materials have attracted extensive attention in energy storage and conversion due to their excellent electrochemical performances. Herein, we report utilization of monolayer SnS2 sheets within SnS2/graphene multilayers for efficient lithium and sodium storage. SnS2/graphene multilayers are synthesized through a solution-phase direct assembly method by electrostatic interaction between monolayer SnS2 and PDDA (polydimethyl diallyl ammonium chloride)-graphene nanosheets. It has been shown that the SnS2/graphene multilayer electrode has a large pseudocapacity contribution for enhanced lithium and sodium storage. Typical batteries deliver a stable reversible capacity of ∼160 mA h g-1 at 2 A g-1 after 2000 cycles for lithium and a stable reversible capacity of ∼142 mA h g-1 at 1 A g-1 after 1000 cycles for sodium. The excellent electrochemical performances of SnS2/graphene multilayers are attributed to the synergistic effect between the monolayer SnS2 sheets and the PDDA-graphene nanosheets. The multilayer structure assembled by different monolayer nanosheets is promising for the further development of 2D materials for energy storage and conversion.

20.
Eur J Obstet Gynecol Reprod Biol ; 264: 162-167, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34304024

RESUMO

OBJECTIVE: To evaluate ventricular contractility and profile heart deformations in fetuses of hyperglycemic mothers using the Speckle tracking imaging (STI). The fractional area change (FAC), global longitudinal strain (GLS) and global sphericity index (GSI) of the 4-chamber view (4-CV) were computed. STUDY DESIGN: Dynamic 4-CV images of 60 fetuses exposed to maternal diabetes (MD) and 60 controls were retrospectively collected between 19 and 37 weeks of gestation. Speckle-tracking analysis was used to compute and compare GSI, GLS and FAC of the right ventricle (RV) and the left ventricle (LV) between the groups. By definition, GSI was the ratio of the epicardial basal-apical length in end-diastole (BAL) to the overall transverse length of RV and LV in end-diastole (TL). The FAC was calculated by dividing the difference between end-diastolic area and end-systolic area by the end-diastolic area. Similarly, the GLS of the RV and LV was obtained by dividing the difference between the endocardial length in end-systole and endocardial length in end-diastole to the endocardial length in end-diastole. Data for conventional echocardiographic parameters, standard biological measurements of fetus and maternal baseline characteristics were also recorded and compared between the groups. Linear regression analysis was performed to assess the association between age, BMI and the inter-ventricular septum thickness (IVST). RESULTS: Gestational age at the time of examination did not differ significantly between the control and gestational diabetes group (p = 0.74). In fetuses exposed to MD, the thickness of the IVS was higher while the FAC of RV, GLS of RV and the GSI were all significantly lower. The FAC and global strain of LV generally decreased with progress in gestation but the difference between the two groups was not statistically significant. Conventional echocardiography in fetuses exposed to MD revealed a lower mitral E/A ratio and a larger myocardial performance index (MPI) of the RV and LV. Although the annular plane systolic excursion (MAPSE), tricuspid annular plane systolic excursion (TAPSE) and septal annular plane systolic excursion (SAPSE) were also lower in this group, the difference was not statistically significant compared to fetuses of the control group. No regression relationship between age, BMI and IVST were noticed in any group. CONCLUSION: This study found that diastolic dysfunction among fetuses of gestational diabetic mothers is accompanied by global cardiac deformation and functional decrease of the RV in systole in the second and third trimester. The GSI, global strain and FAC acquired by SRI can be used as convenient and reliable quantitative parameters in the assessment of cardiac function in fetuses exposed to gestational diabetes.


Assuntos
Diabetes Gestacional , Diabetes Gestacional/diagnóstico por imagem , Ecocardiografia , Feminino , Feto , Ventrículos do Coração/diagnóstico por imagem , Humanos , Gravidez , Estudos Retrospectivos
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