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1.
Plant Cell ; 35(12): 4383-4404, 2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-37738159

RESUMEN

The elimination of seed shattering was a key step in rice (Oryza sativa) domestication. In this paper, we show that increasing the gibberellic acid (GA) content or response in the abscission region enhanced seed shattering in rice. We demonstrate that SLENDER RICE1 (SLR1), the key repressor of GA signaling, could physically interact with the rice seed shattering-related transcription factors quantitative trait locus of seed shattering on chromosome 1 (qSH1), O. sativa HOMEOBOX 15 (OSH15), and SUPERNUMERARY BRACT (SNB). Importantly, these physical interactions interfered with the direct binding of these three regulators to the lignin biosynthesis gene 4-COUMARATE: COENZYME A LIGASE 3 (4CL3), thereby derepressing its expression. Derepression of 4CL3 led to increased lignin deposition in the abscission region, causing reduced rice seed shattering. Importantly, we also show that modulating GA content could alter the degree of seed shattering to increase harvest efficiency. Our results reveal that the "Green Revolution" phytohormone GA is important for regulating rice seed shattering, and we provide an applicable breeding strategy for high-efficiency rice harvesting.


Asunto(s)
Oryza , Oryza/genética , Oryza/metabolismo , Lignina/metabolismo , Giberelinas/metabolismo , Semillas/genética , Semillas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
2.
Proc Natl Acad Sci U S A ; 118(8)2021 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-33558418

RESUMEN

The expansion of anatomically modern humans (AMHs) from Africa around 65,000 to 45,000 y ago (ca. 65 to 45 ka) led to the establishment of present-day non-African populations. Some paleoanthropologists have argued that fossil discoveries from Huanglong, Zhiren, Luna, and Fuyan caves in southern China indicate one or more prior dispersals, perhaps as early as ca. 120 ka. We investigated the age of the human remains from three of these localities and two additional early AMH sites (Yangjiapo and Sanyou caves, Hubei) by combining ancient DNA (aDNA) analysis with a multimethod geological dating strategy. Although U-Th dating of capping flowstones suggested they lie within the range ca. 168 to 70 ka, analyses of aDNA and direct AMS 14C dating on human teeth from Fuyan and Yangjiapo caves showed they derive from the Holocene. OSL dating of sediments and AMS 14C analysis of mammal teeth and charcoal also demonstrated major discrepancies from the flowstone ages; the difference between them being an order of magnitude or more at most of these localities. Our work highlights the surprisingly complex depositional history recorded at these subtropical caves which involved one or more episodes of erosion and redeposition or intrusion as recently as the late Holocene. In light of our findings, the first appearance datum for AMHs in southern China should probably lie within the timeframe set by molecular data of ca. 50 to 45 ka.


Asunto(s)
Arqueología , Cuevas/química , ADN Antiguo/análisis , Fósiles , Sedimentos Geológicos/análisis , Migración Humana/historia , Datación Radiométrica/métodos , China , Historia Antigua , Humanos
3.
Int J Mol Sci ; 25(11)2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38892321

RESUMEN

AMELX mutations cause X-linked amelogenesis imperfecta (AI), known as AI types IE, IIB, and IIC in Witkop's classification, characterized by hypoplastic (reduced thickness) and/or hypomaturation (reduced hardness) enamel defects. In this study, we conducted whole exome analyses to unravel the disease-causing mutations for six AI families. Splicing assays, immunoblotting, and quantitative RT-PCR were conducted to investigate the molecular and cellular effects of the mutations. Four AMELX pathogenic variants (NM_182680.1:c.2T>C; c.29T>C; c.77del; c.145-1G>A) and a whole gene deletion (NG_012494.2:g.307534_403773del) were identified. The affected individuals exhibited enamel malformations, ranging from thin, poorly mineralized enamel with a "snow-capped" appearance to severe hypoplastic defects with minimal enamel. The c.145-1G>A mutation caused a -1 frameshift (NP_001133.1:p.Val35Cysfs*5). Overexpression of c.2T>C and c.29T>C AMELX demonstrated that mutant amelogenin proteins failed to be secreted, causing elevated endoplasmic reticulum stress and potential cell apoptosis. This study reveals a genotype-phenotype relationship for AMELX-associated AI: While amorphic mutations, including large deletions and 5' truncations, of AMELX cause hypoplastic-hypomaturation enamel with snow-capped teeth (AI types IIB and IIC) due to a complete loss of gene function, neomorphic variants, including signal peptide defects and 3' truncations, lead to severe hypoplastic/aplastic enamel (AI type IE) probably caused by "toxic" cellular effects of the mutant proteins.


Asunto(s)
Amelogénesis Imperfecta , Amelogenina , Estudios de Asociación Genética , Mutación , Amelogénesis Imperfecta/genética , Amelogénesis Imperfecta/patología , Humanos , Amelogenina/genética , Masculino , Femenino , Linaje , Fenotipo , Niño , Estrés del Retículo Endoplásmico/genética , Genotipo , Secuenciación del Exoma
4.
Molecules ; 29(8)2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38675519

RESUMEN

The massive amount of water-soluble urea used leads to nutrient loss and environmental pollution in both water and soil. The aim of this study was to develop a novel lignin-based slow-release envelope material that has essential nitrogen and sulfur elements for plants. After the amination reaction with a hydrolysate of yak hair keratin, the coating formulation was obtained by adding different loadings (2, 5, 8, 14 wt%) of aminated lignin (AL) to 5% polyvinyl alcohol (PVA) solution. These formulations were cast into films and characterized for their structure, thermal stability, and mechanical and physicochemical properties. The results showed that the PVA-AL (8%) formulation had good physical and chemical properties in terms of water absorption and mechanical properties, and it showed good degradation in soil with 51% weight loss after 45 days. It is suitable for use as a coating material for fertilizers. Through high-pressure spraying technology, enveloped urea particles with a PVA-AL (8%) solution were obtained, which showed good morphology and slow-release performance. Compared with urea, the highest urea release was only 96.4% after 30 days, conforming to Higuchi model, Ritger-Peppas model, and second-order dynamic model. The continuous nitrogen supply of PVA-AL coated urea to Brassica napus was verified by potting experiments. Therefore, the lignin-based composite can be used as a coating material to produce a new slow-release nitrogen fertilizer for sustainable crop production.


Asunto(s)
Lignina , Alcohol Polivinílico , Urea , Lignina/química , Alcohol Polivinílico/química , Urea/química , Preparaciones de Acción Retardada/química , Fertilizantes , Polímeros/química
5.
BMC Oral Health ; 24(1): 833, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39048989

RESUMEN

Ranula is a mucous cyst that occurs in the sublingual gland (SLG) in the floor of the mouth. It can be classified into two types based on origins: One is the the lesser sublingual gland (LSLG) in the anterior segment and the Rivini duct, which is connected to it, and the other is the greater sublingual gland (GSLG) in the posterior segment. Because of the anatomical characteristics, surgical resection of the cysts carries the risk of damaging adjacent tissues and has a high recurrence rate. Intralesional injection of sclerotherapy may be a better alternative treatment. We summarized 65 cases of ranula treated with intralesional injections of bleomycin(BML). According to the origin of the ranula, 60 cases were from the LSLG and the Rivini duct, and 5 cases were from the GSLG. The results showed that 60 cases of ranula from LSLG and Rivini ducts were 100% cured during the follow-up period. The median number of injections for all patients was 1.16. All 5 cases of ranula from the GSLG did not wholly recover. This study confirmed that BLM intralesional injection is a safe and effective treatment modality for cysts from LSLG or the ducts of Rivini rather than GSLG. Therefore, before treatment, it is necessary to determine the type and origin of the cyst by characterizing its morphology to ensure the effectiveness of the treatment.


Asunto(s)
Bleomicina , Inyecciones Intralesiones , Ránula , Escleroterapia , Bleomicina/administración & dosificación , Bleomicina/uso terapéutico , Humanos , Escleroterapia/métodos , Femenino , Adulto , Masculino , Persona de Mediana Edad , Adolescente , Soluciones Esclerosantes/uso terapéutico , Soluciones Esclerosantes/administración & dosificación , Adulto Joven , Resultado del Tratamiento , Anciano , Niño , Glándula Sublingual
6.
Oral Dis ; 29(8): 3514-3524, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36326426

RESUMEN

OBJECTIVE: Amelogenesis imperfecta (AI) is defined as inherited enamel malformations. LAMA3 (laminin alpha-3) encodes a critical protein component of the basement membrane (laminin-332). Individuals carrying heterozygous LAMA3 mutations have previously been shown to have localized enamel defects. This study aimed to define clinical phenotypes and to discern the genetic etiology for four AI kindreds. MATERIALS AND METHODS: Whole-exome analyses were conducted to search for sequence variants associated with the disorder, and micro-computed tomography (µCT) to characterize the enamel defects. RESULTS: The predominant enamel phenotype was generalized thin enamel with defective pits and grooves. Horizonal bands of hypoplastic enamel with chalky-white discoloration and enamel hypomineralization were also observed and demonstrated by µCT analyses of affected teeth. Four disease-causing LAMA3 mutations (NM_198129.4:c.3712dup; c.5891dup; c.7367del; c.9400G > C) were identified. Compound heterozygous MMP20 mutations (NM_004771.4:c.539A > G; c.692C > T) were also found in one proband with more severe enamel defects, suggesting a mutational synergism on disease phenotypes. Further analyses of the AI-causing mutations suggested that both α3A (short) and α3B (long) isoforms of LAMA3 are essential for enamel formation. CONCLUSIONS: Heterozygous LAMA3 mutations can cause generalized enamel defects (AI1A) with variable expressivity. Laminin-332 is critical not only for appositional growth but also enamel maturation.


Asunto(s)
Amelogénesis Imperfecta , Humanos , Amelogénesis Imperfecta/diagnóstico por imagen , Amelogénesis Imperfecta/genética , Laminina/genética , Microtomografía por Rayos X , Esmalte Dental/diagnóstico por imagen , Proteínas de la Matriz Extracelular/genética , Mutación , Fenotipo , Variación Biológica Poblacional , Linaje
7.
Int Endod J ; 56(8): 943-954, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37159186

RESUMEN

AIM: Biallelic loss-of-function FAM20A mutations cause amelogenesis imperfecta (AI) type IG, better known as enamel renal syndrome (ERS), characterized by severe enamel hypoplasia, delayed/failed tooth eruption, intrapulpal calcifications, gingival hyperplasia and nephrocalcinosis. FAM20A binds to FAM20C, the Golgi casein kinase (GCK) and potentiates its function to phosphorylate secreted proteins critical for biomineralization. While many FAM20A pathogenic mutations have been reported, the pathogeneses of orodental anomalies in ERS remain to be elucidated. This study aimed to identify disease-causing mutations for patients with ERS phenotypes and to discern the molecular mechanism underlying ERS intrapulpal calcifications. METHODOLOGY: Phenotypic characterization and whole exome analyses were conducted for 8 families and 2 sporadic cases with hypoplastic AI. A minigene assay was performed to investigate the molecular consequences of a FAM20A splice-site variant. RNA sequencing followed by transcription profiling and gene ontology (GO) analyses were carried out for dental pulp tissues of ERS and the control. RESULTS: Biallelic FAM20A mutations were demonstrated for each affected individual, including 7 novel pathogenic variants: c.590-5T>A, c.625T>A (p.Cys209Ser), c.771del (p.Gln258Argfs*28), c.832_835delinsTGTCCGACGGTGTCCGACGGTGTC CA (p.Val278Cysfs*29), c.1232G>A (p.Arg411Gln), c.1297A>G (p.Arg433Gly) and c.1351del (p.Gln451Serfs*4). The c.590-5T>A splice-site mutation caused Exon 3 skipping, which resulted in an in-frame deletion of a unique region of the FAM20A protein, p.(Asp197_Ile214delinsVal). Analyses of differentially expressed genes in ERS pulp tissues demonstrated that genes involved in biomineralization, particularly dentinogenesis, were significantly upregulated, such as DSPP, MMP9, MMP20 and WNT10A. Enrichment analyses indicated overrepresentation of gene sets associated with BMP and SMAD signalling pathways. In contrast, GO terms related to inflammation and axon development were underrepresented. Among BMP signalling genes, BMP agonists GDF7, GDF15, BMP3, BMP8A, BMP8B, BMP4 and BMP6 were upregulated, while BMP antagonists GREM1, BMPER and VWC2 showed decreased expression in ERS dental pulp tissues. CONCLUSIONS: Upregulation of BMP signalling underlies intrapulpal calcifications in ERS. FAM20A plays an essential role in pulp tissue homeostasis and prevention of ectopic mineralization in soft tissues. This critical function probably depends upon MGP (matrix Gla protein), a potent mineralization inhibitor that must be properly phosphorylated by FAM20A-FAM20C kinase complex.


Asunto(s)
Amelogénesis Imperfecta , Calcinosis , Proteínas del Esmalte Dental , Nefrocalcinosis , Humanos , Nefrocalcinosis/genética , Nefrocalcinosis/patología , Amelogénesis Imperfecta/genética , Amelogénesis Imperfecta/metabolismo , Amelogénesis Imperfecta/patología , Pulpa Dental/metabolismo , Proteínas del Esmalte Dental/genética , Mutación , Perfilación de la Expresión Génica , Proteínas Portadoras/genética
8.
Int J Mol Sci ; 24(2)2023 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-36674788

RESUMEN

Dental caries, particularly secondary caries, which is the main contributor to dental repair failure, has been the subject of extensive research due to its biofilm-mediated, sugar-driven, multifactorial, and dynamic characteristics. The clinical utility of restorations is improved by cleaning bacteria nearby and remineralizing marginal crevices. In this study, a novel multifunctional dental resin composite (DRC) composed of Sr-N-co-doped titanium dioxide (Sr-N-TiO2) nanoparticles and nano-hydroxyapatite (n-HA) reinforcing fillers with improved antibacterial and mineralization properties is proposed. The experimental results showed that the anatase-phase Sr-N-TiO2 nanoparticles were synthesized successfully. After this, the curing depth (CD) of the DRC was measured from 4.36 ± 0.18 mm to 5.10 ± 0.19 mm, which met the clinical treatment needs. The maximum antibacterial rate against Streptococcus mutans (S. mutans) was 98.96%, showing significant inhibition effects (p < 0.0001), which was experimentally verified to be derived from reactive oxygen species (ROS). Meanwhile, the resin exhibited excellent self-remineralization behavior in an SBF solution, and the molar ratio of Ca/P was close to that of HA. Moreover, the relative growth rate (RGR) of mouse fibroblast L929 indicated a high biocompatibility, with the cytotoxicity level being 0 or I. Therefore, our research provides a suitable approach for improving the antibacterial and mineralization properties of DRCs.


Asunto(s)
Caries Dental , Nanopartículas , Animales , Ratones , Durapatita/farmacología , Resinas Compuestas/farmacología , Antibacterianos/farmacología , Ensayo de Materiales
9.
J Food Sci Technol ; 60(9): 2468-2476, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37424572

RESUMEN

Milk fat-based whipping cream is primarily comprised of cream and whole milk. It has melt-in-the-mouth texture and unique milk flavor. However, milk fat-based whipping cream suffers from poor emulsion stability and foam firmness. The effects of monoacylglycerols (MAGs) with different saturation degrees (M1: 98% saturation, M2: 70% saturation and M3: 30% saturation) on emulsion properties (average particle size, viscosity, and emulsion stability) and whipping properties (overrun, firmness, shape retention ability, and foam stability) of milk fat-based whipping creams were investigated in this study. MAGs significantly decreased particle sizes (from 2.84 to 1.16 µm) and enhanced viscosity (from 350 to 490 cP) of the milk fat-based emulsions (emulsion without MAGs: M0, 5.01 µm, 298 cP) (P < 0.05). MAGs increased the stability of the milk fat-based emulsions with lesser phase separation during centrifugation tests and lower changes in particle sizes and viscosities during temperature cycling tests. Emulsion M1 with highest degree of saturation is less likely to destabilize and phase inverse. The decrease sharply in conductivity can be attributed to the entrapment of large amounts of air. Following that, the conductivity of M1 with low variation indicating high whipping resistance and less likely to coalescence and phase separation. Adding MAGs can significantly enhance overrun (M1: 205.3%, M2: 198.5%, M3: 141.4%) as compared to the control sample (M0: 97.9%) (P < 0.05). In emulsions containing MAGs with high degree of saturation (M1 and M2), firmness (M1: 95 g, M2: 109 g) and shape retention ability of the whipped creams were reduced as compared to control emulsion without MAG (M0: 173 g), but the foam stability (M1: 89%, M2: 91%) was enhanced (M0: 81%); M3 (firmness: 507 g; foam stability: 66%) has the contrasted effects. Whipping cream M2 demonstrated the best whipping properties with high overrun (198.46%), good firmness (109 g), shape retention ability and foam stability (91%). Good quality whipping creams can be obtained by selecting suitable MAGs.

10.
Eur J Nucl Med Mol Imaging ; 49(8): 2716-2722, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35304628

RESUMEN

PURPOSE: Toothache, a common disorder afflicting most people, shows distinct features at different clinical stages. This study aimed to depict metabolic changes in brain and investigate the potential mechanism involved in the aberrant affective behaviors during the natural process of toothache. METHODS: We investigated the spatiotemporal patterns of brain function during the natural course of toothache in a rat model of dental pulp injury (DPI) by using positron emission tomography (PET). RESULTS: Glucose metabolism peaked on the 3rd day and gradually decreased in several brain regions after DPI, which was in line with the behavioral and histological results. PET imaging showed that visual pathway was involved in the regulation of toothache. Meanwhile, the process of emotional regulation underlying toothache was mediated by N-methyl-D-aspartic receptor subunit 2B (NR2B) in the caudal anterior cingulate cortex (cACC). CONCLUSION: Our results revealed the spatiotemporal neurofunctional patterns during toothache process and preliminarily elucidated the role of NR2B in cACC in the regulation of toothache-related affective behaviors.


Asunto(s)
Pulpa Dental , Odontalgia , Animales , Encéfalo/diagnóstico por imagen , Pulpa Dental/diagnóstico por imagen , Giro del Cíngulo , Humanos , Ratas , Tomografía Computarizada por Rayos X
11.
Mol Pharm ; 19(7): 2217-2230, 2022 07 04.
Artículo en Inglés | MEDLINE | ID: mdl-35575590

RESUMEN

Overexpression of apoptotic factors in the inner ear is generally proven to induce ototoxicity. This has aroused research interest in various antiapoptotic drugs, the most representative of which is curcumin (CUR). In this study, two nanoformulations of CUR were developed with sustained-release behavior to improve their protective effects against ototoxic hearing loss (HL), which were the nanoparticles of CUR-loaded poly(lactic acid-glycolic acid) (CUR-PLGA NPs) and CUR-loaded chitosan-coated PLGA NPs (CUR-CS/PLGA NPs). The obtained results revealed that both CUR-NPs provided otoprotection in vitro and in vivo, and their effective doses in guinea pigs were much less than that of dexamethasone, which was clinically used to treat HL. Moreover, relative to CUR and CUR-PLGA NPs, CUR-CS/PLGA NPs exhibited the highest accumulation in HEI-OC1 cells and guinea pigs' cochlea. In pharmacodynamic experiments, the optimal administration timing was investigated, and CUR-CS/PLGA NPs showed sustained efficacy and the best hearing improvement at all tested sound frequencies. Lastly, the protective effect of CUR nanoformulations was further validated via inhibition of Caspase-3 and Bax activation, thereby reducing the concentration of reactive oxygen species and protecting mitochondrial integrity in hair cells. Collectively, CUR-CS/PLGA NPs demonstrated potent and lasting effects against ototoxic HL, making our novel formulation a promising candidate for the alleviation of sensorineural HL.


Asunto(s)
Quitosano , Curcumina , Pérdida Auditiva , Nanopartículas , Animales , Curcumina/farmacología , Cobayas , Pérdida Auditiva/inducido químicamente , Pérdida Auditiva/tratamiento farmacológico , Copolímero de Ácido Poliláctico-Ácido Poliglicólico
12.
Langmuir ; 38(46): 14097-14108, 2022 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-36342971

RESUMEN

Ice recrystallization inhibitors inspired from antifreeze proteins (AFPs) are receiving increasing interest for cryobiology and other extreme environment applications. Here, we present a modular strategy to develop polysaccharide-derived biomimetics, and detailed studies were performed in the case of dextran. Poly(vinyl alcohol) (PVA) which has been termed as one of the most potent biomimetics of AFPs was grafted onto dextran via thiol-ene click chemistry (Dex-g-PVA). This demonstrated that Dex-g-PVA is effective in IRI and its activity increases with the degree of polymerization (DP) (sizes of ice crystals were 18.846 ± 1.759 and 9.700 ± 1.920 µm with DPs of 30 and 80, respectively) and fraction of PVA. By means of the dynamic ice shaping (DIS) assay, Dex-g-PVA is found to engage on the ice crystal surfaces, thus the ice affinity accounts for their IRI activity. In addition, Dex- g-PVA displayed enhanced IRI activity compared to that of equivalent PVA alone. We speculate that the hydrophilic nature of dextran would derive PVA in a stretch conformation that favors ice binding. The modular design can not only offer polysaccharides IRI activity but also favor the ice-binding behavior of PVA.


Asunto(s)
Dextranos , Hielo , Polímeros/química , Cristalización , Proteínas Anticongelantes/química , Polisacáridos
13.
BMC Infect Dis ; 22(1): 408, 2022 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-35473588

RESUMEN

BACKGROUND: Little research has been conducted on the spatio-temporal relationship between the severe cases and the enteroviruses infections of hand, foot and mouth disease (HFMD). This study aimed to investigate epidemic features and spatial clusters of HFMD incidence rates and assess the relationship between Enterovirus 71 (EV71) and Coxsackievirus A16 (CoxA16) and severe cases of HMFD in Gansu province, China. METHODS: Weekly county-specific data on HFMD between 1st January and 31st December 2018 were collected from the China Infectious Disease Information System (CIDIS), including enterovirus type (EV71 and CoxA16), severe and non-severe cases in Gansu province, China. Temporal risk [frequency index (α), duration index (ß) and intensity index (γ)] and spatial cluster analysis were used to assess epidemic features and identify high-risk areas for HFMD. Time-series cross-correlation function and regression model were used to explore the relationship between the ratios of two types of viruses (i.e. EV71/Cox16) (EC) and severe cases index (i.e. severe cases/non-severe cases) (SI) of HFMD. RESULTS: Some counties in Dingxi City, Gansu were identified as a hot spot for the temporal risk indices. Time-series cross-correlation analysis showed that SI was significantly associated with EC (r = 0.417, P < 0.05) over a 4-week time lag. The regression analysis showed that SI was positively associated with EC (ß = 0.04, 95% confidence interval (CI) 0.02-0.06). CONCLUSION: The spatial patterns of HFMD incidence were associated with enteroviruses in Gansu. The research suggested that the EC could be considered a potential early warning sign for predicting severe cases of HFMD in Gansu province.


Asunto(s)
Infecciones por Enterovirus , Enterovirus , Enfermedad de Boca, Mano y Pie , China/epidemiología , Virus ADN , Enfermedad de Boca, Mano y Pie/epidemiología , Humanos
14.
Macromol Rapid Commun ; 43(13): e2200234, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35483003

RESUMEN

Chewing gum residue is hard to decompose and easy to cause pollution, which is highly desirable to realize recycling. In this paper, a chewing gum gel with enhanced mechanical properties and self-healing properties is prepared by using polyvinyl alcohol (PVA) as the backbone in chewing gum residue. The hydrogen bond and the borax ester bond are employed to construct reversible interaction to enhance the self-healing ability. The physical crosslinking is realized by further freeze-thaw treatment to improve its mechanical properties. The gel demonstrates high elongation at break of 610% and strength of 0.11 MPa, as well as excellent self-healing performance and recyclable properties. In particular, the gel with a fast signal response is successfully applied as a wearable strain sensor to monitor different types of human motion. The gel as a sensor exhibits self-healing properties suggesting superior safety and stability, and displays wide linear sensitivity (the gauge factor is 0.417 and 0.170). The gel can be further served to explore temperature changes, implying the application in temperature monitoring. This study develops a novel approach for the recycle and reuse of chewing gum residue. The obtained gel may be a promising candidate for the fabrication of flexible wearable sensor.


Asunto(s)
Goma de Mascar , Dispositivos Electrónicos Vestibles , Humanos , Hidrogeles/química , Enlace de Hidrógeno , Alcohol Polivinílico
15.
Macromol Rapid Commun ; 43(17): e2200182, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35640482

RESUMEN

Traditional adhesives such as cyanoacrylate glue are mostly solvent-based. They are facing the problem of insufficient adhesion to some substrates, and also from the drawback of volatilization and release of small organic molecules in the process of usage. Therefore, a novel adhesive with non-irritating, high adhesive strength, and antibacterial properties is highly required. In this study, a full physically crosslinked zwitterionic poly(betaine sulfonate methacrylate) (PSBMA) hydrogel is proposed. The physical crosslinking interactions endow the hydrogel with good self-healing properties. Furthermore, the pure physical crosslinking hydrogel can form PSBMA powder adhesive after lyophilization and return to the hydrogel state after hydration. The mechanical properties of PSBMA adhesive can be modulated via adjusting the solid content and initiator dosage. Following the cure process similar to that of snail mucus or insect exoskeletons in nature, the adhesion of the PSBMA adhesive is improved at least 100 times than its wet state. In addition, the PSBMA adhesive is easy to be removed due to the dissociation of cross-linked structures in saltwater environments. Moreover, PSBMA adhesive with antifouling properties can effectively prevent the adhesion of proteins and bacteria, which shows potential applications in the assembly of medical devices.


Asunto(s)
Hidrogeles , Adhesivos Tisulares , Adhesivos/química , Antibacterianos/química , Antibacterianos/farmacología , Betaína , Hidrogeles/química , Metacrilatos/química , Adhesivos Tisulares/farmacología
16.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 47(1): 94-100, 2022 Jan 28.
Artículo en Inglés, Zh | MEDLINE | ID: mdl-35545368

RESUMEN

OBJECTIVES: Due to the lack of large-sized pulmonary valved conduit products in clinical practice, hand-sewn expanded polytetrafluoroethylene (ePTFE) valved conduit has been used for right ventricular outflow tract (RVOT) reconstruction in many heart centers around the world. This study aims to summarize the early results of the ePTFE valved conduit and the sewing technology of the conduit in combination with the latest progress, and to provide a reference for the application of ePTFE valved conduit. METHODS: A total of 21 patients using ePTFE valved conduit for RVOT reconstruction in the Second Xiangya Hospital, Central South University from October 2018 to October 2020 were prospectively enrolled in this study. The age at the implantation of the conduit was 4.3 to 43.8 (median 15.1) years old, with weight of (38.9±4.1) kg. In this cohort, 14 patients underwent re-reconstruction of RVOT, including 12 patients with pulmonary regurgitation at 6.3 to 31.0 (median 13.8) years after tetralogy of Fallot (TOF) repair, and 2 patients with failed bovine jugular vein conduit (BJVC). Seven patients underwent Ross operations. Among them, 3 were for aortic valve stenosis, 2 were for aortic regurgitation, and 2 were for both stenosis and regurgitation. The ePTFE valved conduits were standard hand-sewn during the surgery. The 3 leaflets were equal in size with arc-shaped lower edge of the valve sinus. The free edge of the valve leaflets was straight with the length of about 1 mm longer than the diameter. The height of the valve sinus was 4/5 of the diameter. The junction of the valve leaflet was 3/4 of the height of the sinus. The designed leaflets were then continuous non-penetrating sutured into the inner surface of Gore-Tex vessel to make a valved conduit. Valved conduits with diameter of 18, 20, and 22 mm were used in 2, 9, and 10 cases, respectively. The surgical results, postoperative recovery time, and serious complications were summarized, and the changes of postoperative cardiac function status and hemodynamic status of the conduits were investigated. RESULTS: During the implantation of ePTFE valved conduit for RVOT reconstruction, 2 patients underwent mechanical mitral valve replacement with Ross operation, 2 patients with pulmonary regurgitation with repaired TOF underwent left and right pulmonary artery angioplasty, and 1 patient with failed BJVC underwent tricuspid valvuloplasty. The cardiopulmonary bypassing time for patients underwent re-reconstruction of RVOT was (130.9±16.9) min, with aorta clamping for 1 patient to repair the residual defect of the ventricular septum. The cardiopulmonary bypassing and aorta clamping time for Ross operation were (242.7±20.6) min and (145.6±10.5) min, respectively. The duration of postoperative ventilator assistance, intensive care unit stay, and hospital stay were 3.5 h to 7.7 d (median 17.1 h),11.2 h to 29.5 d (median 1.9 d), and 6.0 to 56.0 (median 13.0) d, respectively. All patients survived after discharge from hospital. The follow-up rate after discharge was 100% with median time at 15.0 (13.0 to 39.0) months. No death happened during the follow-up. One patient underwent stent implantation due to right coronary stenosis 2 months after Ross operation. One patient underwent balloon dilation due to right pulmonary artery ostium stenosis 1 year after re-reconstruction of RVOT. The cardiac function of all patients recovered to NYHA class I 6 months after operation. The peak pressure gradient across the valve measured by transthoracic echocardiography before discharge was (9.4±2.6) mmHg (1 mmHg=0.133 kPa), and (18.3±6.1) mmHg at the last follow-up. There was no significant increase in the gradient during the follow-up (P=0.134). No patient suffered from mild or more pulmonary regurgitation. CONCLUSIONS: Hand-sewn ePTFE valved conduit is feasible for RVOT reconstruction. It is a promising material for RVOT reconstruction which can effectively meet clinical need. In our experience, the ePTFE valved conduit is simple to manufacture with satisfactory early outcomes.In the application of ePTFE valved conduit, attention should be paid to implantation indications and postoperative anticoagulation management, especially to the preparation details of the valved conduit, to obtain better function and durability of the conduit after implantation.


Asunto(s)
Implantación de Prótesis de Válvulas Cardíacas , Prótesis Valvulares Cardíacas , Insuficiencia de la Válvula Pulmonar , Obstrucción del Flujo Ventricular Externo , Adolescente , Animales , Bovinos , Constricción Patológica/cirugía , Prótesis Valvulares Cardíacas/efectos adversos , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Implantación de Prótesis de Válvulas Cardíacas/métodos , Humanos , Lactante , Politetrafluoroetileno , Diseño de Prótesis , Insuficiencia de la Válvula Pulmonar/complicaciones , Insuficiencia de la Válvula Pulmonar/cirugía , Estudios Retrospectivos , Resultado del Tratamiento , Obstrucción del Flujo Ventricular Externo/etiología , Obstrucción del Flujo Ventricular Externo/cirugía
17.
Macromol Rapid Commun ; 42(19): e2100324, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34254708

RESUMEN

As a new member of the 2D material family, MXene integrates high metallic conductivity and hydrophilic property simultaneously. It shows tremendous potential in fields of energy storage, sensing, electromagnetic shielding, and so forth. Due to the abundant surface functional groups, the physical and chemical properties of MXene can be tuned by the formation of MXene-polymer composites. The introduction of polymers can expand the interlayer spacing, reduce the distance of ion/electron transport, improve the surface hydrophilicity, and thus guide the assembly of MXene-polymer structures. Herein, the preparation strategies of MXene-polymer composites including physical mixing, surface modification, such as anchoring through TiN and Ti-O-C bonds, bonding through esterification, grafting functional groups through TiOSi/TiOP bonds, photograft reaction, as well as in situ polymerization are highlighted. In addition, the possible mechanisms for each strategy are explained. Furthermore, the applications of MXene-polymer composites obtained by different preparation strategies are summarized. Finally, perspectives and challenges are presented for the designs of MXene-polymer composites.


Asunto(s)
Polímeros , Titanio , Conductividad Eléctrica , Interacciones Hidrofóbicas e Hidrofílicas , Polimerizacion
18.
J Nanobiotechnology ; 19(1): 436, 2021 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-34930292

RESUMEN

BACKGROUND: Oxidative stress contributes to retina ganglion cells (RGCs) loss in variety of ocular diseases, including ocular trauma, ocular vein occlusion, and glaucoma. Scavenging the excessed reactive oxygen species (ROS) in retinal neurovascular unit could be beneficial to RGCs survival. In this study, a polydopamine (PDA)-based nanoplatform is developed to protect RGCs. RESULTS: The PDA nanoparticles efficiently eliminate multi-types of ROS, protect endothelia and neuronal cells from oxidative damage, and inhibit microglia activation in retinas. In an optic nerve crush (ONC) model, single intravitreal injection of PDA nanoparticles could significantly attenuate RGCs loss via eliminating ROS in retinas, reducing the inflammatory response and maintaining barrier function of retinal vascular endothelia. Comparative transcriptome analysis of the retina implied that PDA nanoparticles improve RGCs survival probably by altering the expression of genes involved in inflammation and ROS production. Importantly, as a versatile drug carrier, PDA nanoparticles could deliver brimonidine (a neuroprotection drug) to synergistically attenuate RGCs loss and promote axon regeneration, thus restore visual function. CONCLUSIONS: The PDA nanoparticle-based therapeutic nanoplatform displayed excellent performance in ROS elimination, providing a promising probability for treating retinal degeneration diseases.


Asunto(s)
Indoles/uso terapéutico , Nanopartículas/química , Traumatismos del Nervio Óptico/patología , Polímeros/uso terapéutico , Degeneración Retiniana/tratamiento farmacológico , Animales , Tartrato de Brimonidina/química , Tartrato de Brimonidina/farmacología , Tartrato de Brimonidina/uso terapéutico , Supervivencia Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Células Endoteliales de la Vena Umbilical Humana , Humanos , Peróxido de Hidrógeno/farmacología , Indoles/química , Indoles/farmacología , Macrófagos/citología , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Óxido Nítrico Sintasa de Tipo II/genética , Óxido Nítrico Sintasa de Tipo II/metabolismo , Polímeros/química , Polímeros/farmacología , Especies Reactivas de Oxígeno/química , Retina/efectos de los fármacos , Retina/fisiología , Degeneración Retiniana/patología , Células Ganglionares de la Retina/citología , Células Ganglionares de la Retina/metabolismo , Transcriptoma/efectos de los fármacos
19.
Anal Chem ; 92(1): 1179-1188, 2020 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-31818096

RESUMEN

Multifunctional nanoprobes with both imaging and drug delivery capabilities represent an emerging approach to the diagnosis and treatment of tumor. However, poor accumulation in tumor cells and low drug availability are the main limitations for their further application. Here we show a pH-driven targeting nanoprobe with dual-responsive drug release for persistent luminescence imaging and chemotherapy of tumor. The nanoprobe is constructed by conjugating the pH-low-insertion-peptide (pHLIP) to the surface of the core-shell structure of mesoporous silica-coated persistent luminescence nanoparticles (MSPLNPs) with the peptide GFLG and disulfide bond as bridges. The pHLIP functionalized nanoprobe exhibits higher cellular uptake for A549 and HepG2 cells in an acidic extracellular microenvironment (pH < 6.5) than in normal physiological condition (pH 7.4). The nanoprobe possesses well-defined NIR persistent luminescence performance and can be effectively accumulated in the tumor site, leading to the visual HepG2 tumor target imaging without autofluorescence interference. Furthermore, the nanoprobe realizes the dual-responsive release of doxorubicin loaded in the mesoporous channels in systems containing cathepsin B and glutathione, and can effectively kill tumor cells and inhibit the growth of tumor. This integrated nanoprobe possesses great potential for the diagnosis and treatment of tumors with high specificity and efficiency.


Asunto(s)
Antibióticos Antineoplásicos/farmacología , Materiales Biocompatibles/química , Doxorrubicina/farmacología , Nanopartículas/química , Imagen Óptica , Células A549 , Animales , Antibióticos Antineoplásicos/química , Materiales Biocompatibles/farmacología , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Doxorrubicina/química , Liberación de Fármacos , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Células Hep G2 , Humanos , Concentración de Iones de Hidrógeno , Neoplasias Hepáticas Experimentales/diagnóstico por imagen , Luminiscencia , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Péptidos/química , Péptidos/farmacología , Dióxido de Silicio/química , Dióxido de Silicio/farmacología , Microambiente Tumoral/efectos de los fármacos
20.
Med Sci Monit ; 26: e920481, 2020 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-32086431

RESUMEN

BACKGROUND Tooth bleaching causes a significant decrease in the bonding strength between the resin and human enamel. Nevertheless, the effects of different antioxidant types on the immediate bonding strength of resin and bleached enamel were significantly different. Therefore, the objective of this study was to compare the effects of 2 antioxidants for enhancing the bond strength of the resin to bleached enamel. MATERIAL AND METHODS There were 48 enamel blocks performed from 48 recently extracted maxillary central incisors. There were 8 groups: NC (negative control, no bleached specimens restored without antioxidants); NA (no antioxidant, bleached specimens bonded immediately without any antioxidants); SA30, SA60, and SA120 (bleached specimens accepted the management of 10% sodium ascorbate (SA) for 30 minutes, 60 minutes, and 120 minutes, respectively, before restored); PC30, PC60, and PC120 (bleached specimens received treatment of 5% proanthocyanidins (PC) for 30 minutes, 60 minutes, and 120 minutes, respectively, before restored). We measured the micro-tensile bond strength of specimens and used 2-way ANOVA to analyze the data. RESULTS The mean±standard deviation bond strength measured were: NC, 29.99±4.00; NA, 14.90±1.97; SA30, 18.60±2.20; SA60, 22.57±2.71; SA120, 26.15±3.85; PC30, 16.78±2.29; PC60, 19.13±2.24, PC120, 23.90±2.01 MPa. In addition, the fracture types were mainly of an adhesive mode (88.75%), followed by mixed (7.5%), and cohesive (3.75%). CONCLUSIONS 10% sodium ascorbate provided a comparatively more promising improvement for immediate bond strength than 5% proanthocyanidins when the same duration of antioxidant was applied.


Asunto(s)
Antioxidantes/farmacología , Esmalte Dental/efectos de los fármacos , Blanqueamiento de Dientes , Ácido Ascórbico/farmacología , Recubrimiento Dental Adhesivo , Esmalte Dental/ultraestructura , Humanos , Proantocianidinas/farmacología , Resistencia a la Tracción
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