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1.
Chemistry ; 30(34): e202400947, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38622630

RESUMO

Two crystalline large-sized porous organic cages (POCs) based on conical calix[4]arene (C4A) were designed and synthesized. The four-jaw C4A unit tends to follow the face-directed self-assembly law with the planar triangular building blocks such as tris(4-aminophenyl)amine (TAPA) or 1,3,5-tris(4-aminophenyl)benzene (TAPB) to generate a predictable cage with a stoichiometry of [6+8]. The formation of the large cages is confirmed through their relative molecular mass measured using MALDI-TOF/TOF spectra. The protonated molecular ion peaks of C4A-TAPA and C4A-TAPB were observed at m/z 5109.0 (calculated for C336H240O24N32: m/z 5109.7) and m/z 5594.2 (calculated for C384H264O24N24: m/z 5598.4). C4A-POCs exhibit I-type N2 adsorption-desorption isotherms with the BET surface areas of 1444.9 m2 ⋅ g-1 and 1014.6 m2 ⋅ g-1. The CO2 uptakes at 273 K are 62.1 cm3 ⋅ g-1 and 52.4 cm3 ⋅ g-1 at a pressure of 100 KPa. The saturated iodine vapor static uptakes at 348 K are 3.9 g ⋅ g-1 and 3.5 g ⋅ g-1. The adsorption capacity of C4A-TAPA for SO2 reaches to 124.4 cm3 ⋅ g-1 at 298 K and 1.3 bar. Additionally, the adsorption capacities of C4A-TAPA for C2H2, C2H4, and C2H6 were evaluated.

2.
J Peripher Nerv Syst ; 29(2): 243-251, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38772550

RESUMO

BACKGROUND AND AIMS: This study aimed to report nine Charcot-Marie-Tooth disease (CMT) families with six novel IGHMBP2 mutations in our CMT2 cohort and to summarize the genetic and clinical features of all AR-CMT2S patients reported worldwide. METHODS: General information, clinical and neurophysiological data of 275 axonal CMT families were collected. Genetic screening was performed by inherited peripheral neuropathy related genes panel or whole exome sequencing. The published papers reporting AR-CMT2S from 2014 to 2023 were searched in Pubmed and Wanfang databases. RESULTS: In our CMT2 cohort, we detected 17 AR-CMT2S families carrying IGHMBP2 mutations and eight were published previously. Among these, c.743 T > A (p.Val248Glu), c.884A > G (p.Asp295Gly), c.1256C > A (p.Ser419*), c.2598_2599delGA (p.Lys868Sfs*16), c.1694_1696delATG (p.Asp565del) and c.2509A > T (p.Arg837*) were firstly reported. These patients prominently presented with early-onset typical axonal neuropathy and without respiratory dysfunction. So far, 56 AR-CMT2S patients and 57 different mutations coming from 43 families have been reported in the world. Twenty-nine of 32 missense mutations were clustered in helicase domain and ATPase region. The age at onset ranged from 0.11to 20 years (Mean ± SD: 3.43 ± 3.88 years) and the majority was infantile-onset (<2 years). The initial symptoms included weakness of limbs (19, 29.7%), delayed milestones (12, 18.8%), gait disturbance (11, 17.2%), feet deformity (8, 12.5%), feet drop (8, 12.5%), etc. INTERPRETATION: AR-CMT2S accounted for 6.2% in our CMT2 cohort. We firstly reported six novel IGHMBP2 mutations which expanded the genotypic spectrum of AR-CMT2S. Furthermore, 17 AR-CMT2S families could provide more resources for natural history study, drug research and development.


Assuntos
Doença de Charcot-Marie-Tooth , Estudos de Associação Genética , Humanos , Doença de Charcot-Marie-Tooth/genética , Doença de Charcot-Marie-Tooth/fisiopatologia , Feminino , Masculino , Adulto , China/epidemiologia , Estudos de Coortes , Adolescente , Criança , Mutação , Fatores de Transcrição/genética , Adulto Jovem , Proteínas de Ligação a DNA/genética , Pessoa de Meia-Idade , Linhagem , Pré-Escolar
3.
J Peripher Nerv Syst ; 29(2): 232-242, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38705839

RESUMO

BACKGROUND AND AIMS: Mutations in ganglioside-induced differentiation-associated protein 1 (GDAP1) cause axonal or demyelinating Charcot-Marie-Tooth disease (CMT) with autosomal dominant or recessive inheritance. In this study, we aim to report the genotypic and phenotypic features of GDAP1-related CMT in a Chinese cohort. METHODS: Clinical, neurophysiological, genetic data, and available muscle/brain imaging information of 28 CMT patients with GDAP1 variants were retrospectively collected. RESULTS: We identified 16 GDAP1 pathogenic variants, among which two novel variants c.980dup(p.L328FfsX25) and c.480+4T>G were first reported. Most patients (16/28) presented with AR or AD CMT2K phenotype. Clinical characteristics in our cohort demonstrated that the AR patients presented earlier onset, more severe phenotype compared with the AD patients. Considerable intra-familial phenotypic variability was observed among three AD families. Muscle atrophy and fatty infiltration in the lower extremity were detected by Muscle magnetic resonance imaging (MRI) scans in four patients. MRI showed two AR patients showed more severe muscle involvement of the posterior compartment than those of the anterolateral compartment in the calf. One patient carrying Q38*/H256R variants accompanied with mild periventricular leukoaraiosis. CONCLUSIONS: In this study, we conducted an analysis of clinical features of the GDAP1-related CMT patients, expanded the mutation spectrum in GDAP1 by reporting two novel variants, and presented the prevalent occurrence of the H256R mutation in China. The screening of GDAP1 should be particularly emphasized in Chinese patients with CMT2, given the incomplete penetrance and pathogenic inheritance patterns involving dominant and recessive modes.


Assuntos
Doença de Charcot-Marie-Tooth , Mutação , Proteínas do Tecido Nervoso , Humanos , Doença de Charcot-Marie-Tooth/genética , Doença de Charcot-Marie-Tooth/fisiopatologia , Doença de Charcot-Marie-Tooth/diagnóstico por imagem , Masculino , Feminino , Adulto , Adolescente , Adulto Jovem , Criança , Proteínas do Tecido Nervoso/genética , Pessoa de Meia-Idade , Povo Asiático/genética , China , Estudos Retrospectivos , Linhagem , Pré-Escolar , Fenótipo , População do Leste Asiático
4.
Macromol Rapid Commun ; 45(14): e2400068, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38593218

RESUMO

With the advantages of lightweight and low thermal conductivity properties, polymeric foams are widely employed as thermal insulation materials for energy-saving buildings but suffer from inherent flammability. Flame-retardant coatings hold great promise for improving the fire safety of these foams without deteriorating the mechanical-physical properties of the foam. In this work, four kinds of sulfur-based flame-retardant copolymers are synthesized via a facile radical copolymerization. The sulfur-containing monomers serve as flame-retardant agents including vinyl sulfonic acid sodium (SPS), ethylene sulfonic acid sodium (VS), and sodium p-styrene sulfonate (VSS). Additionally, 2-hydroxyethyl acrylate (HEA) and 4-hydroxybutyl acrylate are employed to enable a strong interface adhesion with polymeric foams through interfacial H-bonding. By using as-synthesized waterborne flame-retardant polymeric coating with a thickness of 600 µm, the coated polyurethane foam (PUF) can achieve a desired V-0 rating during the vertical burning test with a high limiting oxygen index (LOI) of >31.5 vol%. By comparing these sulfur-containing polymeric fire-retardant coatings, poly(VS-co-HEA) coated PUF demonstrates the best interface adhesion capability and flame-retardant performance, with the lowest peak heat release rate of 166 kW m-2 and the highest LOI of 36.4 vol%. This work provides new avenues for the design and performance optimization of advanced fire-retardant polymeric coatings.


Assuntos
Retardadores de Chama , Polímeros , Poliuretanos , Enxofre , Poliuretanos/química , Polímeros/química , Enxofre/química , Retardadores de Chama/análise , Incêndios
5.
Int J Med Sci ; 21(5): 958-964, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38617003

RESUMO

Nowadays dog bite is becoming a world public health problem. Therefore, the study aimed to develop a dog bite animal model that is helpful to solve these problems. In this study, the skull of an adult dog was scanned. The three-dimensional model of the dog maxillofacial bones and dentition was built by MIMICS. Next, the model was printed with Co-Cr alloy by using selective laser sintering technology to develop the dog bite simulation pliers. Then, to simulate dog bite to most, the maximum bite force of the pliers was measured and actions contained in dog bite process was analyzed. Afterwards, according to action analysis results, rabbits were bitten by the prepared instrument in actions that simulate dog's bite. Finally, the reproducibility and controllability of this animal model of dog bite injuries was validated in an in vivo study. The results showed a reliable animal model of dog bite injuries has been developed in this study. The sites and severities of the injuries could be adjusted as the operator wishes and the animal model of dog bite injuries was highly repeatable. This study also indicates the feasibility of using digital technology in establishing animal bite models.


Assuntos
Mordeduras e Picadas , Crânio , Cães , Animais , Coelhos , Reprodutibilidade dos Testes , Ligas , Modelos Animais
6.
Plant Cell Rep ; 43(8): 205, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39088074

RESUMO

KEY MESSAGE: Transcriptomics and phenotypic data analysis identified 24 transcription factors (TFs) that play key roles in regulating the competitive accumulation of lignin and flavonoids. Tilia tuan Szyszyl. (T. tuan) is a timber tree species with important ecological and commercial value. However, its highly lignified pericarp results in a low seed germination rate and a long dormancy period. In addition, it is unknown whether there is an interaction between the biosynthesis of flavonoids and lignin as products of the phenylpropanoid pathway during seed development. To explore the molecular regulatory mechanism of lignin and flavonoid biosynthesis, T. tuan seeds were harvested at five stages (30, 60, 90, 120, and 150 days after pollination) for lignin and flavonoid analyses. The results showed that lignin accumulated rapidly in the early and middle stages (S1, S3, and S4), and rapid accumulation of flavonoids during the early and late stages (S1 and S5). High-throughput RNA sequencing analysis of developing seeds identified 50,553 transcripts, including 223 phenylpropanoid biosynthetic pathway genes involved in lignin accumulation grouped into 3 clusters, and 106 flavonoid biosynthetic pathway genes (FBPGs) grouped into 2 clusters. Subsequent WGCNA and time-ordered gene co-expression network (TO-GCN) analysis revealed that 24 TFs (e.g., TtARF2 and TtWRKY15) were involved in flavonoids and lignin biosynthesis regulation. The transcriptome data were validated by qRT-PCR to analyze the expression profiles of key enzyme-coding genes. This study revealed that there existed a competitive relationship between flavonoid and lignin biosynthesis pathway during the development of T. tuan seeds, that provide a foundation for the further exploration of molecular mechanisms underlying lignin and flavonoid accumulation in T. tuan seeds.


Assuntos
Flavonoides , Regulação da Expressão Gênica de Plantas , Lignina , Sementes , Lignina/metabolismo , Lignina/biossíntese , Flavonoides/metabolismo , Flavonoides/biossíntese , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Perfilação da Expressão Gênica , Transcriptoma/genética , Redes Reguladoras de Genes , Genes de Plantas , Vias Biossintéticas/genética
7.
Int J Mol Sci ; 25(12)2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38928203

RESUMO

The morphological architecture of inflorescence influences seed production. The regulatory mechanisms underlying alfalfa (Medicago sativa) inflorescence elongation remain unclear. Therefore, in this study, we conducted a comparative analysis of the transcriptome, proteome, and metabolome of two extreme materials at three developmental stages to explore the mechanisms underlying inflorescence elongation in alfalfa. We observed the developmental processes of long and short inflorescences and found that the elongation capacity of alfalfa with long inflorescence was stronger than that of alfalfa with short inflorescences. Furthermore, integrative analysis of the transcriptome and proteome indicated that the phenylpropanoid biosynthesis pathway was closely correlated with the structural formation of the inflorescence. Additionally, we identified key genes and proteins associated with lignin biosynthesis based on the differential expressed genes and proteins (DEGs and DEPs) involved in phenylpropanoid biosynthesis. Moreover, targeted hormone metabolome analysis revealed that IAA, GA, and CK play an important role in the peduncle elongation of alfalfa inflorescences. Based on omics analysis, we detected key genes and proteins related to plant hormone biosynthesis and signal transduction. From the WGCNA and WPCNA results, we furthermore screened 28 candidate genes and six key proteins that were correlated with lignin biosynthesis, plant hormone biosynthesis, and signaling pathways. In addition, 19 crucial transcription factors were discovered using correlation analysis that might play a role in regulating candidate genes. This study provides insight into the molecular mechanism of inflorescence elongation in alfalfa and establishes a theoretical foundation for improving alfalfa seed production.


Assuntos
Regulação da Expressão Gênica de Plantas , Inflorescência , Lignina , Medicago sativa , Proteínas de Plantas , Transcriptoma , Medicago sativa/genética , Medicago sativa/crescimento & desenvolvimento , Medicago sativa/metabolismo , Inflorescência/crescimento & desenvolvimento , Inflorescência/genética , Inflorescência/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Lignina/biossíntese , Lignina/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Reguladores de Crescimento de Plantas/genética , Proteoma/metabolismo , Perfilação da Expressão Gênica , Proteômica/métodos , Metaboloma , Multiômica
8.
Pharm Dev Technol ; 29(4): 291-299, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38466377

RESUMO

In the current work, we aimed to prepare a liraglutide-loaded porous microsphere-gel composite system. By employing polyethylene glycol (PEG) as a porogenic agent and poly (lactic-co-glycolic acid) copolymer (PLGA) as a carrier, the liraglutide microspheres were prepared and dispersed in a temperature-sensitive gel made of poloxamer 407 (F-127) and poloxamer 188 (F-68), which served as the gel matrix, to construct the composite system. The porous microsphere-gel composite system demonstrated prolonged and steady drug release, with a reduction to 4.7% in the initial release within 1 d, according to data from in vitro release tests. The drug release from the porous microspheres decreased from 53% to 29% during the rapid release phase as the PEG concentration increased and the release rate slowed down. In vivo experiments in rats revealed that the composite system prolonged the release period by about 10 d. The pharmacokinetic parameter AUC0-1 was decreased by 24.78 ng/ml*h, the initial burst release was decreased, and the blood drug concentration fluctuation was lessened. The construction of a porous microsphere-gel composite matrix offers a novel approach to the systems with a sustained, long-lasting release that utilizes rational design.


Assuntos
Liberação Controlada de Fármacos , Géis , Liraglutida , Microesferas , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ratos Sprague-Dawley , Animais , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Porosidade , Liraglutida/administração & dosagem , Liraglutida/farmacocinética , Ratos , Masculino , Portadores de Fármacos/química , Polietilenoglicóis/química , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/farmacocinética , Hipoglicemiantes/química , Ácido Láctico/química , Poloxâmero/química , Preparações de Ação Retardada , Ácido Poliglicólico/química
9.
J Am Chem Soc ; 145(32): 17613-17620, 2023 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-37531461

RESUMO

Solid-binding peptides are a simple and versatile tool for the non-covalent modification of solid material surfaces, and a variety of peptides have been developed by reference to natural proteins or de novo design. Here, for the first time, we report the discovery of a bicyclic peptide targeting the heterogeneous material polypropylene by combining phage display technology and next-generation sequencing. We find that the enrichment properties of bicyclic peptides capable of binding to polypropylene are distinct from linear peptides, as reflected in amino acid abundance and a trend toward negative net charges and high hydrophobicity. The selected bicyclic peptide has a higher binding affinity for polypropylene compared with a previously reported linear peptide, enabling the hydrophilic and adhesive properties of the polypropylene to be more effectively enhanced. Our work paves the way for the exploration and utilization of conformational-restricted cyclic peptides as a new family of functionally evolvable agents for material surface modification.


Assuntos
Bacteriófagos , Polipropilenos , Peptídeos/química , Peptídeos Cíclicos/química , Aminoácidos , Biblioteca de Peptídeos
10.
J Am Chem Soc ; 145(44): 24108-24115, 2023 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-37788442

RESUMO

Protocells have garnered considerable attention from cell biologists, materials scientists, and synthetic biologists. Phase-separating coacervate microdroplets have emerged as a promising cytomimetic model because they can internalize and concentrate components from dilute surrounding environments. However, the membrane-free nature of such coacervates leads to coalescence into a bulk phase, a phenomenon that is not representative of the cells they are designed to mimic. Herein, we develop a membranized peptide coacervate (PC) with oppositely charged oligopeptides as the molecularly crowded cytosol and a metal-phenolic network (MPN) coating as the membrane. The hybrid protocell efficiently internalizes various bioactive macromolecules (e.g., bovine serum albumin and immunoglobulin G) (>90%) while also resisting radicals due to the semipermeable cytoprotective membrane. Notably, the resultant PC@MPNs are capable of anabolic cascade reactions and remain in discrete protocellular populations without coalescence. Finally, we demonstrate that the MPN protocell membrane can be postfunctionalized with various functional molecules (e.g., folic acid and fluorescence dye) to more closely resemble actual cells with complex membranes, such as recognition molecules, which allows for drug delivery. This membrane-bound cytosolic protocell structure paves the way for innovative synthetic cells with structural and functional complexity.


Assuntos
Células Artificiais , Células Artificiais/química , Peptídeos , Soroalbumina Bovina/química , Substâncias Macromoleculares
11.
Langmuir ; 39(33): 11839-11850, 2023 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-37561909

RESUMO

Vitamin E derivatives are particularly effective in chemotherapy drug development because they are nontoxic, biocompatible, and selective. Among them, α-tocopheryl succinate (α-TOS) can act synergistically with some chemotherapeutic agents. However, its hydrophobicity limits its systemic administration, and localized formulations are not available. Herein, we developed an injectable hydrogel based on self-assembled micelles of a triblock amphiphilic derivative of α-TOS (PEG-2VES), in which doxorubicin (DOX) was encapsulated in the core of the micelles for combined chemotherapy. A molecule of α-TOS was grafted onto each end of poly(ethylene glycols) (PEGs) of different lengths. Hydrogels were prepared by dissolving the polymers or the DOX-loaded micelles in water at room temperature. The subcutaneously injected hydrogels kept their shape and sustainably released the payloads over 7 days without any noticeable inflammatory response. In vitro and in vivo results confirmed the synergistic antitumor effects of the hydrogel and loaded drug. Furthermore, DOX-loaded hydrogels showed greater therapeutic efficiency and fewer toxic side effects than DOX alone. Overall, this hydrogel acts as a multifunctional system that can deliver drug, improve the therapeutic effect, and minimize drug toxicity.


Assuntos
Micelas , Vitamina E , Hidrogéis/toxicidade , Doxorrubicina/farmacologia , Portadores de Fármacos/toxicidade , Polietilenoglicóis/farmacologia , alfa-Tocoferol , Linhagem Celular Tumoral
12.
Environ Sci Technol ; 57(31): 11634-11642, 2023 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-37498082

RESUMO

As the concentration of microplastics/microspheres (MPs) in coastal and estuarine regions increases, the likelihood of disease outbreaks and epidemics also rises. Our study investigated the impact of polyvinyl chloride MPs (PVC-MPs) on white spot syndrome virus (WSSV) infection in shrimp. The results revealed that PVC-MPs obviously increased WSSV replication in vivo, leading to a high mortality rate among the larvae and facilitating the horizontal transmission of WSSV. Furthermore, the data of WSSV loads detected together with qPCR, agarose gel electrophoresis, and flow cytometry approaches indicated that PVC-MPs could interact with the virus to prolong survival and maintain the virulence of WSSV at different temperatures and pH values. In terms of host resistance, metabolomics and transcriptomics analysis demonstrated that exposure to PVC-MPs upregulated metabolic concentrations and gene expressions associated with phospholipid metabolism that were associated with innate immunity responses. Particularly, PVC-MPs stimulated the synthesis of phosphatidylcholine (PC) and induced lipid peroxidation. The inhibition of PC on Stimulator of Interferon Genes (STING) translocation from the endoplasmic reticulum to the Golgi apparatus reduces expression of the innate immunity genes (IFN-like genes Vago4 and Vago5) regulated by STING signaling pathways, resulting in a significant decrease in the shrimp's resistance to WSSV infection. Notably, a recovery operation in which the exposed larvae were transferred to a MPs-free aquatic environment led to decreased WSSV infectivity over time, indicating the restoration of antiviral properties in shrimp. Overall, these findings highlight that MPs promote shrimp susceptibility to WSSV in two aspects: host immune defense and viral virulence.


Assuntos
Penaeidae , Vírus da Síndrome da Mancha Branca 1 , Animais , Microplásticos , Plásticos , Vírus da Síndrome da Mancha Branca 1/genética , Virulência , Imunidade Inata/genética , Penaeidae/genética
13.
J Peripher Nerv Syst ; 28(4): 608-613, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37584201

RESUMO

BACKGROUND AND AIMS: Biallelic variants in the sorbitol dehydrogenase (SORD) gene have been identified as the genetic cause of autosomal recessive (AR) peripheral neuropathy (PN) manifesting as Charcot-Marie-Tooth disease type 2 (CMT2) or distal hereditary motor neuropathy (dHMN). We aim to observe the genetic and clinical spectrum of a cohort of patients with SORD-related PN (SORD-PN). METHODS: A total of 107 patients with AR or sporadic CMT2/dHMN underwent molecular diagnosis by whole-exome sequencing and subsequent Sanger sequencing validation. Available phenotypic data for SORD-PN were collected and analyzed. RESULTS: Eleven (10.28%) of 107 patients were identified as SORD-PN, including four with CMT2 and seven with dHMN. The SORD variant c.210 T > G;p.His70Gln in F-d3 was firstly reported and subsequent analysis showed that it resulted in loss of SORD enzyme function. Evidence of subclinical muscle involvement was frequently detected in patients with SORD-PN, including mildly to moderately elevated serum creatine kinase (CK) levels in 10 patients, myogenic electrophysiological changes in one patient, and muscle edema in five patients undergoing lower extremity MRI. Fasting serum sorbitol level was 88-fold higher in SORD-PN patients (9.69 ± 1.07 mg/L) than in healthy heterozygous subjects (0.11 ± 0.01 mg/L) and 138-fold higher than in healthy controls (0.07 ± 0.02 mg/L). INTERPRETATION: The novel SORD variant c.210 T > G;p.His70Gln and evidence of subclinical muscle involvement were identified, which expanded the genetic and clinical spectrum of SORD-PN. Subclinical muscle involvement might be a common but easily overlooked clinical feature. The serum CK and fasting serum sorbitol levels were expected to be sensitive biomarkers confirmed by follow-up cohort study.


Assuntos
Doença de Charcot-Marie-Tooth , Neuropatia Hereditária Motora e Sensorial , Humanos , L-Iditol 2-Desidrogenase/genética , Seguimentos , Doença de Charcot-Marie-Tooth/genética , Músculos , Sorbitol , Mutação/genética , Linhagem , Neuropatia Hereditária Motora e Sensorial/genética
14.
Macromol Rapid Commun ; 44(18): e2300262, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37335812

RESUMO

Simultaneously enhancing the fire safety and mechanical properties of epoxy resin (EP) remains a persistent challenge. Herein, a high-efficient phosphaphenanthrene-based flame retardant (FNP) is synthesized using 3,5-diamino-1,2,4-triazole, 4-formylbenzoic acid, and 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide. Due to the presence of active amine groups, FNP is employed as a co-curing agent for fabricating EP composites with outstanding fire safety and mechanical properties. EP containing 8 wt% FNP (EP/8FNP) achieves a vertical burning (UL-94) V-0 rating with a limiting oxygen index of 31%. Meanwhile, FNP declines the peak heat release rate, total heat release, and total smoke release of EP/8FNP by 41.1%, 31.8%, and 16.0%, respectively, compared to those of unmodified EP. The increased fire safety of EP/FNP composites is because FNP promotes the formation of an intumescent, compact, and cross-linking char layer for EP/FNP composites, and releases P-containing substances and noncombustible gases in the gas phase during combustion. In addition, EP/8FNP exhibits 20.3% and 5.4% increase in the flexural strength and modulus compared with those of pure EP. Furthermore, FNP enhances the glass transition temperature of EP/FNP composites from 141.6 °C for pure EP to 147.3 °C for EP/8FNP. Therefore, this work is conducive to the future development of fabricating fire-safe EP composites with enhanced mechanical properties.


Assuntos
Resinas Epóxi , Retardadores de Chama , Gases , Vidro , Temperatura Alta
15.
BMC Ophthalmol ; 23(1): 128, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-36991349

RESUMO

BACKGROUND: This study evaluated the vascular changes in the macular and peripapillary regions before and after silicone oil (SO) removal in patients with rhegmatogenous retinal detachment. METHODS: This single-center case series assessed patients who underwent SO removal at one hospital. Patients who underwent pars plana vitrectomy and perfluoropropane gas tamponade (PPV + C3F8) were selected as controls. Superficial vessel density (SVD) and superficial perfusion density (SPD) in the macular and peripapillary regions were assessed by optical coherence tomography angiography (OCTA). Best-corrected visual acuity (BCVA) was assessed using LogMAR. RESULTS: Fifty eyes were administered SO tamponade, 54 SO tamponade(SOT) contralateral eyes, 29 PPV + C3F8 eyes, and 27 PPV + C3F8 contralateral eyes were selected. SVD and SPD in the macular region were lower in eyes administered SO tamponade compared with SOT contralateral eyes (P < 0.01). Except for the central area, SVD and SPD in the other areas of the peripapillary region were reduced after SO tamponade without SO removal (P < 0.01). No significant differences were found in SVD and SPD between PPV + C3F8 contralateral and PPV + C3F8 eyes. After SO removal, macular SVD and SPD showed significant improvements compared with preoperative values, but no improvements in SVD and SPD were observed in the peripapillary region. BCVA (LogMAR) decreased post-operation and was negatively correlated with macular SVD and SPD. CONCLUSIONS: SVD and SPD are decreased during SO tamponade and increased in the macular region of eyes that underwent SO removal, suggesting a possible mechanism for reduced visual acuity during or after SO tamponade. TRIAL REGISTRATION: Registration date: 22/05/2019; Registration number, ChiCTR1900023322; Registration site, Chinese Clinical Trial Registry (ChiCTR).


Assuntos
Macula Lutea , Descolamento Retiniano , Humanos , Angiografia , Descolamento Retiniano/cirurgia , Estudos Retrospectivos , Óleos de Silicone , Tomografia de Coerência Óptica , Vitrectomia
16.
BMC Surg ; 23(1): 285, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37726728

RESUMO

BACKGROUND: Bipedicular/unipedicular percutaneous kyphoplasty are common treatments for OVCF, and there are no studies to show which is more beneficial for AVCF. The purpose of this study was to investigate the clinical efficacy of BPKP or UPKP in the treatment of AVCF. METHODS: The clinical data of AVCF patients treated by PKP were retrospectively analyzed. They were divided into two groups according to the surgical approach. General demographic data, perioperative complications, and general information related to surgery were recorded for both groups. The preoperative and postoperative vertebral height difference, vertebral local Cobb angle, lumbar pain VAS score and lumbar JOA score were counted for both groups. The above data were compared preoperatively, postoperatively and between the two groups. RESULTS: 25 patients with AVCF were successfully included and all were followed up for at least 12 months, with no complications during the follow-up period. 10 patients in the BPKP group and 15 patients in the UPKP group, with no statistically significant differences in general information between the two groups. The VAS scores of patients in the BPKP group were lower than those in the UPKP group at 12 months after surgery, and the differences were statistically significant, and there were no statistically significant differences between the two groups at other follow-up time points. In the BPKP group, 80% of patients had symmetrical and more homogeneous bone cement dispersion. 50% of patients in the UPKP group had a lateral distribution of bone cement and uneven bone cement distribution, and the difference in bone cement distribution between the two groups was statistically significant. CONCLUSION: For the treatment of AVCF, the clinical efficacy of both surgical approaches is basically the same. The distribution of cement is more symmetrical and uniformly diffused in the BPKP group, and the clinical efficacy VAS score is lower in the long-term follow-up. Bipedicular percutaneous kyphoplasty is recommended for the treatment of AVCF. THE ETHICAL REVIEW BATCH NUMBER: XZXY-LJ-20161208-047.


Assuntos
Fraturas por Compressão , Cifoplastia , Fraturas da Coluna Vertebral , Humanos , Fraturas por Compressão/cirurgia , Estudos de Casos e Controles , Cimentos Ósseos/uso terapêutico , Estudos Retrospectivos , Fraturas da Coluna Vertebral/cirurgia
17.
Dent Traumatol ; 39(2): 140-146, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36366969

RESUMO

BACKGROUND/AIM: There are no epidemiological reports focused on the oral and maxillofacial surgery emergency department in the West China Hospital of Stomatology. The aim of this study was to analyse the epidemiological characteristics of emergency patients admitted for Trauma and Plastic Surgery Department of the West China Hospital of Stomatology from 2016-2019. MATERIALS AND METHODS: In this retrospective study, 5220 patients with complete medical records were evaluated. The following data were collected: gender, age, etiology, disease type distribution, anatomic injury site and treatment modality. RESULTS: There were 3046 males and 2174 females (ratio 1.40:1), with an average age of 16.2 years. The largest group was children aged between 3 and 6 years old (28.3%). Maxillofacial injuries were the most common condition (87.3%), which mostly occurred on the forehead (29.7%), followed by the lips (27.8%). A fall was the leading cause of injury (59.9%), especially in patients younger than 6 years old. There were 327 cases of maxillofacial space infections (MSI), and the mandibular third molars were the most common tooth associated with odontogenic infections (36.2%). Univariable analysis identified that multiple-space infection, visit time and systemic conditions were the risk factors for being admitted to the hospital for treatment. There were 116 patients (2.2%) with bleeding as the main complaint, and most of the maxillofacial bleeding patients could be stopped by compression (52.6%). CONCLUSION: Males and children aged younger than 6 years were the highest risk populations. Trauma accounted for the majority of emergency patients in maxillofacial surgery. Most maxillofacial injuries involved the forehead and were mainly caused by accidental falls. The proportion of MSI was not high, but serious cases may be life-threatening. The causes of bleeding were diverse, and the bleeding was easy to control.


Assuntos
Traumatismos Maxilofaciais , Fraturas Cranianas , Masculino , Criança , Feminino , Humanos , Adolescente , Pré-Escolar , Estudos Retrospectivos , Emergências , Acidentes por Quedas , China , Acidentes de Trânsito
18.
Molecules ; 28(11)2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37298982

RESUMO

Conjugated polymer photocatalysts for hydrogen production have the advantages of an adjustable structure, strong response in the visible light region, adjustable energy levels, and easy functionalization. Using an atom- and step-economic direct C-H arylation method, dibromocyanostilbene was polymerized with thiophene, dithiophene, terthiophene, and fused thienothiophene and dithienothiophene, respectively, to produce donor-acceptor (D-A)-type linear conjugated polymers containing different thiophene derivatives with different conjugation lengths. Among them, the D-A polymer photocatalyst constructed from dithienothiophene could significantly broaden the spectral response, with a hydrogen evolution rate up to 12.15 mmol h-1 g-1. The results showed that the increase in the number of fused rings on thiophene building blocks was beneficial to the photocatalytic hydrogen production of cyanostyrylphene-based linear polymers. For the unfused dithiophene and terthiophene, the increase in the number of thiophene rings enabled more rotation freedom between the thiophene rings and reduced the intrinsic charge mobility, resulting in lower hydrogen production performance accordingly. This study provides a suitable process for the design of electron donors for D-A polymer photocatalysts.


Assuntos
Hidrogênio , Doadores de Tecidos , Humanos , Polímeros , Tiofenos
19.
Biophys J ; 121(20): 3774-3784, 2022 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-36146938

RESUMO

Genome architecture mapping (GAM) is a recently developed methodology that offers the cosegregation probability of two genomic segments from an ensemble of thinly sliced nuclear profiles, enabling us to probe and decipher three-dimensional chromatin organization. The cosegregation probability from GAM binned at 1 Mb, which thus probes the length scale associated with the genomic separation greater than 1 Mb, is, however, not identical to the contact probability obtained from Hi-C, and its correlation with interlocus distance measured with fluorescence in situ hybridization is not so good as the contact probability. In this study, by using a polymer-based model of chromatins, we derive a theoretical expression of the cosegregation probability as well as that of the contact probability and carry out quantitative analyses of how they differ from each other. The results from our study, validated with in silico GAM analysis on three-dimensional genome structures from fluorescence in situ hybridization, suggest that to attain strong correlation with the interlocus distance, a properly normalized version of cosegregation probability needs to be calculated based on a large number of nuclear slices (n>103).


Assuntos
Cromatina , Polímeros , Hibridização in Situ Fluorescente/métodos , Mapeamento Cromossômico/métodos , Cromatina/genética , Probabilidade
20.
J Biol Chem ; 297(1): 100806, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34022223

RESUMO

Sensing noxiously high temperatures is crucial for living organisms to avoid heat-induced injury. The TRPV1 channel has long been known as a sensor for noxious heat. However, the mechanism of how this channel is activated by heat remains elusive. Here we found that a series of polyols including sucrose, sorbitol, and hyaluronan significantly elevate the heat activation threshold temperature of TRPV1. The modulatory effects of these polyols were only observed when they were perfused extracellularly. Interestingly, mutation of residues E601 and E649 in the outer pore region of TRPV1 largely abolished the effects of these polyols. We further observed that intraplantar injection of polyols into the hind paws of rats reduced their heat-induced pain response. Our observations not only suggest that the extracellular regions of TRPV1 are critical for the modulation of heat activation by polyols, but also indicate a potential role of polyols in reducing heat-induced pain sensation.


Assuntos
Temperatura Alta , Polímeros/farmacologia , Canais de Cátion TRPV/metabolismo , Sequência de Aminoácidos , Animais , Capsaicina/farmacologia , Espaço Extracelular/química , Feminino , Células HEK293 , Humanos , Ativação do Canal Iônico/efeitos dos fármacos , Polímeros/química , Prótons , Ratos Wistar , Canais de Cátion TRPV/química
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