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1.
Ann Surg ; 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38881456

RESUMEN

OBJECTIVE: This study evaluated the efficacy of various local management strategies for diabetic foot ulcers (DFUs). BACKGROUND: Several surgical and non-surgical local interventional approaches are available for the treatment of DFUs. The comparative effectiveness of different treatments is unknown, and it remains unclear which approach is the optimal choice for DFUs treatment due to limited direct comparisons. METHODS: We did a systematic review and meta-analysis to select the optimal approach to DFUs local management. We searched Medline, Embase, Web of Science, and ClinicalTrials.gov from inception to September 1, 2023, to identify relevant randomized controlled trials (RCTs). We analysed data by pairwise meta-analyses with a random-effects model. A network meta-analysis using the surface under the cumulative ranking curve (SUCRA) was performed to evaluate the comparative efficacy of different interventional approaches in the early (within 12 wk) and late stages (over 12 wk). RESULTS: 141 RCTs involving 14076 patients and exploring 14 interventional strategies were eligible for inclusion. Most studies (102/141) had at least one risk-of-bias dimension. Good consistency was observed during the analysis. Local pairwise comparisons demonstrated obvious differences in the early-stage healing rate and early- and late-stage healing times, while no significant difference in the late-stage healing rate or adverse events were noted. SUCRAs identified the standard of care (SOC) + decellularized dressing (DD), off-loading (OL), and autogenous graft (AG) as the three most effective interventions within 12 weeks for both healing rate (97%, mean rank: 1.4; 90%, mean rank: 2.3; 80.8%, mean rank: 3.5, respectively) and healing time (96.7%, mean rank: 1.4; 83.0%, mean rank: 3.0; 76.8%, mean rank: 3.8, respectively). After 12 weeks, local drug therapy (LDT) (89.5%, mean rank: 2.4) and OL (82.4%, mean rank: 3.3) ranked the highest for healing rate, and OL (100.0%, mean rank: 1.0) for healing time. With respect to adverse events, moderate and high risks were detected in the SOC + DD (53.7%, mean rank: 7.0) and OL (24.4%, mean rank: 10.8) groups, respectively. CONCLUSION: The findings suggest that OL provided considerable benefits for DFU healing in both the early and late stages, but the high risk of adverse events warrants caution. SOC+DD may be the preferred option in the early stages, with an acceptable risk of adverse events.

2.
PLoS Comput Biol ; 19(6): e1011218, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37289843

RESUMEN

Synthetic lethality (SL) occurs when mutations in two genes together lead to cell or organism death, while a single mutation in either gene does not have a significant impact. This concept can also be extended to three or more genes for SL. Computational and experimental methods have been developed to predict and verify SL gene pairs, especially for yeast and Escherichia coli. However, there is currently a lack of a specialized platform to collect microbial SL gene pairs. Therefore, we designed a synthetic interaction database for microbial genetics that collects 13,313 SL and 2,994 Synthetic Rescue (SR) gene pairs that are reported in the literature, as well as 86,981 putative SL pairs got through homologous transfer method in 281 bacterial genomes. Our database website provides multiple functions such as search, browse, visualization, and Blast. Based on the SL interaction data in the S. cerevisiae, we review the issue of duplications' essentiality and observed that the duplicated genes and singletons have a similar ratio of being essential when we consider both individual and SL. The Microbial Synthetic Lethal and Rescue Database (Mslar) is expected to be a useful reference resource for researchers interested in the SL and SR genes of microorganisms. Mslar is open freely to everyone and available on the web at http://guolab.whu.edu.cn/Mslar/.


Asunto(s)
Neoplasias , Saccharomyces cerevisiae , Humanos , Saccharomyces cerevisiae/genética , Mutaciones Letales Sintéticas , Mutación , Genoma Bacteriano/genética , Bases de Datos Genéticas , Neoplasias/genética
3.
Am J Hematol ; 99(4): 662-678, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38197307

RESUMEN

Chimeric antigen receptor (CAR) T-cell therapy, an innovative immunotherapeutic against relapsed/refractory B-cell lymphoma, faces challenges due to frequent viral infections. Despite this, a comprehensive review addressing risk assessment, surveillance, and treatment management is notably absent. This review elucidates immune response compromises during viral infections in CAR-T recipients, collates susceptibility risk factors, and deliberates on preventive strategies. In the post-pandemic era, marked by the Omicron variant, new and severe threats to CAR-T therapy emerge, necessitating exploration of preventive and treatment measures for COVID-19. Overall, the review provides recommendations for viral infection prophylaxis and management, enhancing CAR-T product safety and recipient survival.


Asunto(s)
Linfoma de Células B , Receptores Quiméricos de Antígenos , Virosis , Humanos , Receptores Quiméricos de Antígenos/uso terapéutico , Inmunoterapia Adoptiva/efectos adversos , Linfoma de Células B/terapia , Virosis/etiología , Antígenos CD19 , Tratamiento Basado en Trasplante de Células y Tejidos
4.
Small ; 19(31): e2205291, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36635000

RESUMEN

Fabricating polymer electrolyte membranes (PEMs) simultaneously with high ion conductivity and selectivity has always been an ultimate goal in many membrane-integrated systems for energy conversion and storage. Constructing broader ion-conducting channels usually enables high-efficient ion conductivity while often bringing increased crossover of other ions or molecules simultaneously, resulting in decreased selectivity. Here, the ultra-small carbon dots (CDs) with the selective barriers are self-assembled within proton-conducting channels of PEMs through electrostatic interaction to enhance the proton conductivity and selectivity simultaneously. The functional CDs regulate the nanophase separation of PEMs and optimize the hydration proton network enabling higher-efficient proton transport. Meanwhile, the CDs within proton-conducting channels prevent fuel from permeating selectively due to their repelling and spatial hindrance against fuel molecules, resulting in highly enhanced selectivity. Benefiting from the improved conductivity and selectivity, the open-circuit voltage and maximum power density of the direct methanol fuel cell (DMFC) equipped with the hybrid membranes raised by 23% and 93%, respectively. This work brings new insight to optimize polymer membranes for efficient and selective transport of ions or small molecules, solving the trade-off of conductivity and selectivity.

5.
J Pharmacol Exp Ther ; 386(1): 70-79, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37230799

RESUMEN

Portal hypertension (PT) commonly occurs in cirrhosis. Nitric oxide (NO) imbalance contributes to PT via reduced soluble guanylyl cyclase (sGC) activation and cGMP production, resulting in vasoconstriction, endothelial cell dysfunction, and fibrosis. We assessed the effects of BI 685509, an NO-independent sGC activator, on fibrosis and extrahepatic complications in a thioacetamide (TAA)-induced cirrhosis and PT model. Male Sprague-Dawley rats received TAA twice-weekly for 15 weeks (300-150 mg/kg i.p.). BI 685509 was administered daily for the last 12 weeks (0.3, 1, and 3 mg/kg p.o.; n = 8-11 per group) or the final week only (Acute, 3 mg/kg p.o.; n = 6). Rats were anesthetized to measure portal venous pressure. Pharmacokinetics and hepatic cGMP (target engagement) were measured by mass spectrometry. Hepatic Sirius Red morphometry (SRM) and alpha-smooth muscle actin (αSMA) were measured by immunohistochemistry; portosystemic shunting was measured using colored microspheres. BI 685509 dose-dependently increased hepatic cGMP at 1 and 3 mg/kg (3.92 ± 0.34 and 5.14 ± 0.44 versus 2.50 ± 0.19 nM in TAA alone; P < 0.05). TAA increased hepatic SRM, αSMA, PT, and portosystemic shunting. Compared with TAA, 3 mg/kg BI 685509 reduced SRM by 38%, αSMA area by 55%, portal venous pressure by 26%, and portosystemic shunting by 10% (P < 0.05). Acute BI 685509 reduced SRM and PT by 45% and 21%, respectively (P < 0.05). BI 685509 improved hepatic and extrahepatic cirrhosis pathophysiology in TAA-induced cirrhosis. These data support the clinical investigation of BI 685509 for PT in patients with cirrhosis. SIGNIFICANCE STATEMENT: BI 685509 is an NO-independent sGC activator that was tested in a preclinical rat model of TAA-induced nodular, liver fibrosis, portal hypertension, and portal systemic shunting. BI 685509 reduced liver fibrosis, portal hypertension, and portal-systemic shunting in a dose-dependent manner, supporting its clinical assessment to treat portal hypertension in patients with cirrhosis.


Asunto(s)
Hipertensión Portal , Cirrosis Hepática Experimental , Ratas , Masculino , Animales , Guanilil Ciclasa Soluble/farmacología , Tioacetamida/efectos adversos , Ratas Sprague-Dawley , Cirrosis Hepática Experimental/inducido químicamente , Cirrosis Hepática Experimental/tratamiento farmacológico , Hipertensión Portal/tratamiento farmacológico , Cirrosis Hepática/inducido químicamente , Cirrosis Hepática/tratamiento farmacológico , Cirrosis Hepática/complicaciones , Hígado , GMP Cíclico
6.
J Pharmacol Exp Ther ; 384(3): 382-392, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36507845

RESUMEN

Activation of soluble guanylate cyclase (sGC) to restore cyclic guanosine monophosphate (cGMP) and improve functionality of nitric oxide (NO) pathways impaired by oxidative stress is a potential treatment of diabetic and chronic kidney disease. We report the pharmacology of BI 685509, a novel, orally active small molecule sGC activator with disease-modifying potential. BI 685509 and human sGC α1/ß1 heterodimer containing a reduced heme group produced concentration-dependent increases in cGMP that were elevated modestly by NO, whereas heme-free sGC and BI 685509 greatly enhanced cGMP with no effect of NO. BI 685509 increased cGMP in human and rat platelet-rich plasma treated with the heme-oxidant ODQ; respective EC50 values were 467 nM and 304 nM. In conscious telemetry-instrumented rats, BI 685509 did not affect mean arterial pressure (MAP) or heart rate (HR) at 3 and 10 mg/kg (p.o.), whereas 30 mg/kg decreased MAP and increased HR. Ten days of BI 685509 at supratherapeutic doses (60 or 100 mg/kg p.o., daily) attenuated MAP and HR responses to a single 100 mg/kg challenge. In the ZSF1 rat model, BI 685509 (1, 3, 10, and 30 mg/kg per day, daily) coadministered with enalapril (3 mg/kg per day) dose-dependently reduced proteinuria and incidence of glomerular sclerosis; MAP was modestly reduced at the higher doses versus enalapril. In the 7-day rat unilateral ureteral obstruction model, BI 685509 dose-dependently reduced tubulointerstitial fibrosis (P < 0.05 at 30 mg/kg). In conclusion, BI 685509 is a potent, orally bioavailable sGC activator with clear renal protection and antifibrotic activity in preclinical models of kidney injury and disease. SIGNIFICANCE STATEMENT: BI 685509 is a novel small soluble guanylate cyclase (sGC) molecule activator that exhibits an in vitro profile consistent with that of an sGC activator. BI 685509 reduced proteinuria and glomerulosclerosis in the ZSF1 rat, a model of diabetic kidney disease (DKD), and reduced tubulointerstitial fibrosis in a rat 7-day unilateral ureteral obstruction model. Thus, BI 685509 is a promising new therapeutic agent and is currently in phase II clinical trials for chronic kidney disease and DKD.


Asunto(s)
Insuficiencia Renal Crónica , Obstrucción Ureteral , Ratas , Humanos , Animales , Guanilil Ciclasa Soluble/metabolismo , Guanilato Ciclasa/metabolismo , Obstrucción Ureteral/patología , Riñón/metabolismo , Progresión de la Enfermedad , Proteinuria/tratamiento farmacológico , Fibrosis , Enalapril/uso terapéutico , Óxido Nítrico/metabolismo , GMP Cíclico/metabolismo
7.
Opt Express ; 31(4): 6514-6528, 2023 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-36823905

RESUMEN

Light detection and ranging (lidar) is widely accepted as an indispensable sensor for autonomous vehicles. There are two fundamental challenges in a lidar system: optical beam steering technique and ranging method. Optical phased array (OPA) is considered as one of the most promising beam steering schemes due to its solid state, compact size, and high reliability. As for ranging method, time-of-flight and frequency-modulate continuous-wave (FMCW) are commonly utilized in numerous research. However, they are impractical to commercial OPA lidar due to either requiring excessive optical power or the poor stability, high complexity, and high insertion loss of the FMCW source. As a result, the development of OPA lidars is significantly hindered by the lack of a feasible ranging method. In this paper, we present a phase-modulated continuous-wave (PhMCW) ranging method with excellent ranging accuracy and precision. Ranging error as low as 0.1 cm and precision on the order of 3.5 cm are achieved. In addition, theoretical and experimental study on simultaneous velocity measurement is carried out and velocity error as low as 0.15 cm/s is obtained. Finally, we develop a proof-of-concept OPA-PhMCW lidar and obtain a point cloud with excellent fidelity. Our work paves a novel approach to solid-state, cost-effective and high-performance OPA lidars.

8.
J Chem Phys ; 159(12)2023 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-38127373

RESUMEN

How to fabricate perpendicularly oriented domains (PODs) of lamellar and cylinder phases in block copolymer thin films remains a major challenge. In this work, via a coarse-grained molecular dynamics simulation study, we report a solvent evaporation strategy starting from a mixed solution of A-b-B-type diblock copolymers (DBCs) and single-chain nanoparticles (SCNPs) with the same composition, which is capable of spontaneously generating PODs in drying DBC films induced by the interface segregation of SCNPs. The latter occurs at both the free surface and substrate and, consequently, neutralizes the interface selectivity of distinct blocks in DBCs, leading to spontaneous formation of PODs at both interfaces. The interface segregation of SCNPs is related to the weak solvophilicity of the internal cross-linker units. A mean-field theory calculation demonstrates that the increase in the chemical potential of SCNPs in the bulk region drives their interface segregation along with solvent evaporation. We believe that such a strategy can be useful in regulating the PODs of DBC films in practical applications.

9.
J Pharmacol Exp Ther ; 382(3): 266-276, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35779860

RESUMEN

Diabetic nephropathy is a leading cause of end-stage renal disease, characterized by endothelial dysfunction and a compromised glomerular permeability barrier. Dysregulation of the angiopoietin 1 (ANGPT1)/angiopoietin 2 (ANGPT2) signaling axis is implicated in disease progression. We recently described the discovery of an IgG1 antibody, O010, with therapeutic potential to elevate circulating endogenous ANGPT1, a tyrosine kinase with Ig and epidermal growth factor (EGF) homology domains-2 (TIE2) agonist. Studies are described that detail the effect of various ANGPT1-elevating strategies to limit progression of renal dysfunction in diabetic-obese (db/db) mice. Results demonstrate that adeno-associated virus- or DNA minicircle-directed overexpression of ANGPT1 elicits a reduction in albuminuria (56%-73%) and an improvement in histopathology score (18% reduction in glomerulosclerosis). An improved acetylcholine response in isolated aortic rings was also observed indicative of a benefit on vascular function. In separate pharmacokinetic studies, an efficacious dose of the ANGPT1 DNA minicircle increased circulating levels of the protein by >80%, resulting in a concomitant suppression of ANGPT2. At a dose of O010-producing maximal elevation of circulating ANGPT1 achievable with the molecule (60% increase), no suppression of ANGPT2 was observed in db/db mice, suggesting insufficient pathway engagement; no reduction in albuminuria or improvement in histopathological outcomes were observed. To pinpoint the mechanism resulting in lack of efficacy, we demonstrate, using confocal microscopy, an interference with TIE2 translocation to adherens junctions, resulting in a loss of protection against vascular permeability normally conferred by ANGPT1. Results demonstrated the essential importance of ANGPT1 to maintain the glomerular permeability barrier, and, due to interference of O010 with this process, led to the discontinuation of the molecule for clinical development. SIGNIFICANCE STATEMENT: This body of original research demonstrates that elevation of systemic angiopoietin 1 (ANGPT1) is protective against diabetic nephropathy. However, using a novel biotherapeutic approach to elevate systemic ANGPT1 renoprotection was not observed; we demonstrate that protection was lost due to interference of the therapeutic with ANGPT1/ tyrosine kinase with Ig and EGF homology domains-2 translocation to adherens junctions. Thus, the clinical development of the antibody was terminated.


Asunto(s)
Angiopoyetina 1 , Diabetes Mellitus , Nefropatías Diabéticas , Albuminuria , Angiopoyetina 1/genética , Angiopoyetina 1/metabolismo , Angiopoyetina 2/genética , Angiopoyetina 2/metabolismo , Animales , Nefropatías Diabéticas/tratamiento farmacológico , Nefropatías Diabéticas/genética , Factor de Crecimiento Epidérmico , Ratones , Ratones Obesos , Proteínas Tirosina Quinasas
10.
Soft Matter ; 19(1): 128-136, 2022 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-36477470

RESUMEN

Polar groups have long been recognized to greatly influence the glass transition temperature (Tg) of polymers, but understanding the underlying physical mechanism remains a challenge. Here, we study the glass formation of ring-opening metathesis polymerization (ROMP) copolymers containing polar groups by employing all-atom molecular dynamics simulations. We show that although the number of hydrogen bonds (NHB) and the cohesive energy density increase linearly as the content of polar groups (fpol) increases, the Tg of ROMP copolymers increases with the increase of fpol in a nonlinear fashion, and tends to plateau for sufficiently high fpol. Importantly, we find that the increase rate of Gibbs free energy for HB breaking gradually slows down with the increase of fpol, indicating that the HB is gradually stabilized. Therefore, Tg is jointly determined by NHB and the strength of HBs in the system, while the latter dominates. Although NHB increases linearly with increasing fpol, the HB strength increases slowly with increasing fpol, which leads to a decreasing rate of increase in Tg.

11.
Proc Natl Acad Sci U S A ; 116(20): 10156-10161, 2019 05 14.
Artículo en Inglés | MEDLINE | ID: mdl-31028142

RESUMEN

Transient receptor potential canonical type 6 (TRPC6) is a nonselective receptor-operated cation channel that regulates reactive fibrosis and growth signaling. Increased TRPC6 activity from enhanced gene expression or gain-of-function mutations contribute to cardiac and/or renal disease. Despite evidence supporting a pathophysiological role, no orally bioavailable selective TRPC6 inhibitor has yet been developed and tested in vivo in disease models. Here, we report an orally bioavailable TRPC6 antagonist (BI 749327; IC50 13 nM against mouse TRPC6, t1/2 8.5-13.5 hours) with 85- and 42-fold selectivity over the most closely related channels, TRPC3 and TRPC7. TRPC6 calcium conductance results in the stimulation of nuclear factor of activated T cells (NFAT) that triggers pathological cardiac and renal fibrosis and disease. BI 749327 suppresses NFAT activation in HEK293T cells expressing wild-type or gain-of-function TRPC6 mutants (P112Q, M132T, R175Q, R895C, and R895L) and blocks associated signaling and expression of prohypertrophic genes in isolated myocytes. In vivo, BI 749327 (30 mg/kg/day, yielding unbound trough plasma concentration ∼180 nM) improves left heart function, reduces volume/mass ratio, and blunts expression of profibrotic genes and interstitial fibrosis in mice subjected to sustained pressure overload. Additionally, BI 749327 dose dependently reduces renal fibrosis and associated gene expression in mice with unilateral ureteral obstruction. These results provide in vivo evidence of therapeutic efficacy for a selective pharmacological TRPC6 inhibitor with oral bioavailability and suitable pharmacokinetics to ameliorate cardiac and renal stress-induced disease with fibrosis.


Asunto(s)
Cardiomegalia/tratamiento farmacológico , Nefroesclerosis/tratamiento farmacológico , Canal Catiónico TRPC6/antagonistas & inhibidores , Animales , Evaluación Preclínica de Medicamentos , Fibrosis , Células HEK293 , Corazón/efectos de los fármacos , Humanos , Riñón/efectos de los fármacos , Ratones
12.
Foot Ankle Surg ; 28(7): 1120-1128, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35450789

RESUMEN

BACKGROUND: The superiority of negative pressure wound therapy (NPWT) to standard gauze dressings for managing open fractures of the lower limbs remains controversial. This study aimed to comprehensively compare their clinical efficacy through a meta-analysis using randomized controlled trials (RCTs) alone. We hypothesized that NPWT would be more superior against infections. METHODS: A literature search was implemented in various databases, including PubMed, Web of Science, Medline, Clinicaltrial.gov, and Cochrane Library, etc, to screen eligible RCTs. All included RCTs were evaluated for risk of bias using the Cochrane Collaboration tool. In accordance with the heterogeneity assessment, a fixed-effect or random-effect model was chosen for the data analysis. RESULTS: Ten RCTs, including 2780 patients, were eligible for the meta-analysis. We found that patients in the NPWT group showed a lower overall infection rate (MD=0.70, 95% CI: 0.54-0.90, P = 0.005), acute wound infection rate (MD = 0.35, 95% CI: 0.16-0.77, P = 0.009), and shorter hospital stay (MD = 24.00, 95% CI: 6.82-84.46, P < 0.00001) compared with the control group. The NPWT group showed a higher proportion of patients with wound coverage than the control group. No significant difference was found between the two groups in terms of function score and other complications, including deep infection rate, amputation, and bone nonunion. CONCLUSIONS: From the pooled results, we suggest that NPWT may be superior than traditional gauze dressings for managing open fractures of the lower limbs.


Asunto(s)
Fracturas Abiertas , Terapia de Presión Negativa para Heridas , Vendajes , Fracturas Abiertas/terapia , Humanos , Extremidad Inferior , Terapia de Presión Negativa para Heridas/métodos , Ensayos Clínicos Controlados Aleatorios como Asunto , Infección de la Herida Quirúrgica/etiología , Infección de la Herida Quirúrgica/terapia , Cicatrización de Heridas
13.
J Am Chem Soc ; 143(50): 21433-21442, 2021 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-34886669

RESUMEN

Modern electrochemical and electronic devices require advanced electrolytes. Liquid crystals have emerged as promising electrolyte candidates due to their good fluidity and long-range order. However, the mesophase of liquid crystals is variable upon heating, which limits their applications as high-temperature electrolytes, e.g., implementing anhydrous proton conduction above 100 °C. Here, we report a highly stable thermotropic liquid-crystalline electrolyte based on the electrostatic self-assembly of polyoxometalate (POM) clusters and zwitterionic polymer ligands. These electrolytes can form a well-ordered mesophase with sub-10 nm POM-based columnar domains, attributed to the dynamic rearrangement of polymer ligands on POM surfaces. Notably, POMs can serve as both electrostatic cross-linkers and high proton conductors, which enable the columnar domains to be high-temperature-stable channels for anhydrous proton conduction. These nanochannels can maintain constant columnar structures in a wide temperature range from 90 to 160 °C. This work demonstrates the unique role of POMs in developing high-performance liquid-crystalline electrolytes, which can provide a new route to design advanced ion transport systems for energy and electronic applications.

14.
Cancer Sci ; 112(11): 4785-4798, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34506683

RESUMEN

Osteosarcoma has been the most common malignant bone tumor in children and adolescents, while the 5-y survival of osteosarcoma patients gained no significant improvement over the past decades. This study aimed to explore the role of ferroptosis-related genes (FRGs) in the development and prognosis of osteosarcoma. The datasets of osteosarcoma patients including RNA sequencing data and clinical information were acquired from the TRGET and Gene Expression Omnibus (GEO) databases. The identification of molecular subgroups with different FRG expression patterns was achieved through nonnegative matrix factorization (NMF) clustering. The prognostic model was constructed using the least absolute shrinkage and selection operator (LASSO) algorithm and multivariate Cox regression analysis. The ESTIMATE algorithm was applied for determining the stromal score, immune score, ESTIMA score, and tumor purity of osteosarcoma patients. Functional analyses including Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses, Gene Set Enrichment Analysis (GSEA), and Gene Set Variation Analysis (GSVA) were conducted to explore the underlying mechanisms in the development and prognosis of osteosarcoma. Two molecular subgroups with different FRGs expression patterns were identified. The molecular subgroups with higher immune score and more active immune status showed better prognostic survival. On the basis of FRGs, a prognostic model and a nomogram integrating clinical characteristics were constructed and their prediction efficiency for osteosarcoma prognosis were well validated. Gene functional enrichment analysis showed that these differentially expressed FRGs were mainly enriched in immunity-related signaling pathways, indicating that FRGs may affect the development and prognosis of osteosarcoma by regulating the immune microenvironment. The expression profiles of FRGs were closely related to the immunity status and prognostic survival of osteosarcoma patients. The interaction between ferroptosis and immunity in the development of osteosarcoma could provide a new insight into the exploration of molecular mechanisms and targeted therapies of osteosarcoma patients.


Asunto(s)
Algoritmos , Neoplasias Óseas/genética , Ferroptosis/genética , Ferroptosis/inmunología , Osteosarcoma/genética , Adolescente , Neoplasias Óseas/inmunología , Neoplasias Óseas/mortalidad , Niño , Bases de Datos Genéticas , Femenino , Perfilación de la Expresión Génica , Humanos , Masculino , Nomogramas , Osteosarcoma/inmunología , Osteosarcoma/mortalidad , Pronóstico , Análisis de Regresión , Análisis de Secuencia de ARN
15.
Soft Matter ; 17(24): 5897-5906, 2021 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-34037067

RESUMEN

We use coarse-grained molecular dynamics simulations to study the self-assembly behavior of polyoxometalate (POM) nanoparticles (NPs) decorated with mobile polymer ligands under melt conditions. We demonstrate that due to the mobile nature of the grafted ligands on the NP surface, NPs have the ability to expose a part of their surfaces, leading to a block-copolymer-like self-assembly behavior. The exposed NP surface serves as one block and the grafted ligand polymers as another. This system has a strong ability to self-assemble into long-range ordered structures such as block copolymers due to large incompatibility between POM and ligand polymers, i.e., POM NPs can form lamellar, cylindrical, and spherical structures, which are consistent with previous experimental results. More importantly, these ordered structures are on the sub-10 nm scale, which is an important requirement for many applications. At low graft density, we find a new inverse-cylindrical structure formation where polymers form cylinders and POMs form a continuous network structure. A full self-assembly phase diagram is constructed which illustrates rules to manipulate the self-assembly structures of NPs decorated with mobile polymer ligands. We hope that these computational results will be useful for the new design of nanostructures with improved optical or electronic functions.

16.
J Chem Phys ; 155(5): 054901, 2021 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-34364327

RESUMEN

By using coarse-grained molecular dynamics simulations, we have investigated the structure and dynamics of supercooled single-chain cross-linked nanoparticle (SCNP) melts having a range of cross-linking degrees ϕ. We find a nearly linear increase in glass-transition temperature (Tg) with increasing ϕ. Correspondingly, we have also experimentally synthesized a series of polystyrene-based SCNPs and have found that the measured Tg estimated from differential scanning calorimetry is qualitatively consistent with the trend predicted by our simulation estimates. Experimentally, an increase in Tg as large as ΔTg = 61 K for ϕ = 0.36 is found compared with their linear chain counterparts, indicating that the changes in dynamics with cross-links are quite appreciable. We attribute the increase in Tg to the enlarged effective hard-core volume and the corresponding reduction in the free volume of the polymer segments. Topological constraints evidently frustrate the local packing. In addition, the introduction of intra-molecular cross-linking bonds slows down the structural relaxation and simultaneously enhances the local coupling motion on the length scales within SCNPs. Consequently, a more pronounced dynamical heterogeneity (DH) is observed for larger ϕ, as quantified by measuring the dynamical correlation length through the four-point susceptibility parameter, χ4. The increase in DH is directly related to the enhanced local cooperative motion derived from intra-molecular cross-linking bonds and structural heterogeneity derived from the cross-linking process. These results shed new light on the influence of intra-molecular topological constraints on the segmental dynamics of polymer melts.

17.
Arch Orthop Trauma Surg ; 141(5): 783-793, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-32448929

RESUMEN

INTRODUCTION: The aim of this study is to provide an updated meta-analysis comparing the benefits and clinical outcomes between high flexion (HF)-TKA and standard (S)-TKA. MATERIALS AND METHODS: A detailed database analysis was carried out using Web of Science, PubMed, EMBASE, Cochrane Library, MEDLINE and Clinicaltrial.gov, to identify eligible studies. The meta-analysis and sensitivity analysis were performed using Review Manager 5.3 software and STATA 12.0. RESULTS: Twenty-two randomized control trials (RCTs), including 2841 patients and 4268 knees, were eligible for the meta-analysis. The pooled results of subgroup analysis reveal that there was significant difference between HF-TKA and S-TKA in each subgroup in terms of postoperative ROM, with a higher degree of knee flexion for HF-TKA than S-TKA. However, no statistical difference was identified between HF-TKA and S-TKA in other clinical outcomes including various functional scores and complications. CONCLUSIONS: On the basis of this meta-analysis, we can recommended HF-TKA as an alternative choice to S-TKA for patients requiring higher knee flexion in their daily activities.


Asunto(s)
Artroplastia de Reemplazo de Rodilla/métodos , Rango del Movimiento Articular/fisiología , Humanos , Rodilla/cirugía , Complicaciones Posoperatorias , Estudios Prospectivos , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento
18.
Foot Ankle Surg ; 27(3): 263-270, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33199156

RESUMEN

BACKGROUND: The aim of this study is to compare the clinical efficacy between the ligament augmentation reconstruction system (LARS) and the modified Brostrom-Gould (MBG) operations in the treatment of chronic ankle instability. METHODS: We searched the MEDLINE, EMBASE, PubMed, Web of Science, the Cochrane library, and the Clinicaltrial.gov databases for eligible studies. The Review Manager 5.3 software was applied to compare various postoperative functional scoring, ankle stability and complications between the two groups. RESULTS: Four randomized controlled trials including a total of 209 patients were conducted. No significant difference was found in terms of postoperative FAOS, FAAM, ankle stability and complications between the LARS and MBG group. CONCLUSIONS: The present meta-analysis suggested that there was no clinical superiority for the LARS operation over the MBG operation for patients with chronic ankle instability.


Asunto(s)
Articulación del Tobillo/cirugía , Inestabilidad de la Articulación/cirugía , Ligamentos Laterales del Tobillo/cirugía , Procedimientos Ortopédicos/métodos , Procedimientos de Cirugía Plástica/métodos , Ensayos Clínicos Controlados Aleatorios como Asunto , Adolescente , Adulto , Femenino , Estudios de Seguimiento , Humanos , Masculino , Procedimientos Ortopédicos/efectos adversos , Dimensión del Dolor , Complicaciones Posoperatorias , Calidad de Vida , Procedimientos de Cirugía Plástica/efectos adversos , Resultado del Tratamiento , Adulto Joven
19.
Macromol Rapid Commun ; 41(24): e1900655, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32134543

RESUMEN

Polymeric single-chain nanoparticles (SCNPs) are soft nano-objects synthesized by intramolecular crosslinking of isolated single polymer chains. Syntheses of such SCNPs usually need to be performed in a dilute solution. In such a condition, the bonding probability of the two active crosslinking units at a short contour distance along the chain backbone is much higher than those which are far away from each other. Such a reaction condition often results in local spheroidization and, therefore, the formation of loosely packed structures. How to inhibit the local spheroidization and improve the compactness of SCNPs is thus a major challenge for the syntheses of SCNPs. In this study, computer simulations are performed and the fact that a precollapse of the polymer chain conformation in a cosolvent condition can largely improve the probability of the crosslinking reactions at large contour distances is demonstrated, favoring the formations of closely packed globular structures. As a result, the formed SCNPs can be more spherical and have higher compactness than those fabricated in ultradilute good solvent solution in a conventional way. It is believed this simulation work can provide a insight into the effective syntheses of SCNPs with spherical conformations and high compactness.


Asunto(s)
Nanopartículas , Polímeros , Simulación por Computador , Solventes
20.
Phys Chem Chem Phys ; 22(20): 11400-11408, 2020 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-32374336

RESUMEN

We study the interfacial structure and dynamics of a polymer nanocomposite (PNC) composed of octaaminophenyl polyhedral oligomeric silsesquioxane (OAPS) and poly(2-vinylpyridine) (P2VP) by performing full atomistic molecular dynamics simulations. There are eight aminophenyl groups grafted on the surface of the OAPS particle and the particle has a size comparable to the Kuhn segment of P2VP. These aminophenyl groups can form hydrogen bonds (HBs) with pyridine rings from surrounding P2VP chains. We found that OAPS can form ∼2 HBs on average with surrounding polymer chains. The effect of the HBs is investigated in detail by either switching on or off these HBs in our simulation. By analyzing the interfacial static packing structure and dynamic properties, we demonstrate that the system has an ∼1 nm interface width, similar to the OAPS particle size. We also found that HBs can prevent the further penetration of polymers into the inner zone (grafting layer) of the OAPS, and therefore keep the P2VP chains in the outer layer (>1 nm), remaining bulk-like, which is well consistent with experimental results. In addition, we found that NP diffusion is coupled to the absorbed polymer chains, which also dramatically slows down the diffusion of polymer segments in return. The core-shell model in which the NP and absorbed polymers diffuse as a single object is validated here at the full atomistic level. These results provide atomistic insights into the unique structure and dynamics in the small attractive NP-polymer interfacial region. We hope these results will be helpful for the understanding of peculiar phenomena in attractive polymer nanocomposites containing small NPs.

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