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1.
Ann Plast Surg ; 90(1 Suppl 1): S103-S110, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-37075300

RESUMEN

BACKGROUND: As we all know, the numbers of aesthetic surgery are increasing around the world. After the surgery, the scar would be a problematic issue for both the surgeons and the patients. Silicone has proven to be effective for keloids, hypertrophic scars, and prevention of scar formation in many literatures for a long time. In terms of scar prevention, silicone has been used in the form of silicone sheets in early times, which is later improved to be the form of silicone gel with the advantage of easier usage. Although silicone gel has improved greatly in the aspect of appearance and convenience of the silicone sheets, there are still some disadvantages of the gel form. Therefore, the LeniScar silicone stick (AnsCare) is invented. OBJECTIVE: This article aimed to compare the results of scar treatment and prevention of the AnsCare LeniScar Silicone Stick versus the traditional silicone gel (Dermatix Ultra). METHODS: This study was a prospective, nonblinded, randomized clinical study. There were a total of 68 patients from September 2018 to January 2020. Patients were divided into 2 groups with AnsCare (n = 43) and Dermatix (n = 25), who both were required to schedule regular outpatient clinic follow-up, and photographs were taken before use, 1, 2, and 3 months later after the usage for the record. The physician assessed the scar condition by the Vancouver Scar Scale (VSS). The scores of the VSS were further analyzed and compared. RESULTS: The overall P value of total score of VSS was 0.635, which indicates that there is no significant difference in using AnsCare LeniScar Silicone Stick versus Dermatix Ultra silicone gel in terms of scar prevention and treatment. Individual items of VSS such as pliability, height, vascularity, and pigmentation all show no significant statistical difference in the 2 treatment products, with P = 0.980, 0.778, 0.528, and 0.366, respectively. CONCLUSION: Traditional Dermatix Ultra silicone gel has been effective in the treatment of scar formation. AnsCare LeniScar Silicone Stick is statistically not different from the Dermatix Ultra silicone gel when comparing the treatment results of scar prevention. Furthermore, the AnsCare LeniScar Silicone Stick has the advantages of being time-saving with no need to wait for it to dry and application of precise amount to precise location, preventing waste or overuse.


Asunto(s)
Cicatriz Hipertrófica , Queloide , Humanos , Geles de Silicona/uso terapéutico , Estudios Prospectivos , Cicatriz Hipertrófica/etiología , Cicatriz Hipertrófica/prevención & control , Queloide/etiología , Queloide/prevención & control , Resultado del Tratamiento
2.
Anesthesiology ; 136(4): 551-566, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-35226725

RESUMEN

BACKGROUND: Postoperative pulmonary complications are common. Aging and respiratory disease provoke airway hyperresponsiveness, high-risk surgery induces diaphragmatic dysfunction, and general anesthesia contributes to atelectasis and peripheral airway injury. This study therefore tested the hypothesis that inhalation of penehyclidine, a long-acting muscarinic antagonist, reduces the incidence of pulmonary complications in high-risk patients over the initial 30 postoperative days. METHODS: This single-center double-blind trial enrolled 864 patients age over 50 yr who were scheduled for major upper-abdominal or noncardiac thoracic surgery lasting 2 h or more and who had an Assess Respiratory Risk in Surgical Patients in Catalonia score of 45 or higher. The patients were randomly assigned to placebo or prophylactic penehyclidine inhalation from the night before surgery through postoperative day 2 at 12-h intervals. The primary outcome was the incidence of a composite of pulmonary complications within 30 postoperative days, including respiratory infection, respiratory failure, pleural effusion, atelectasis, pneumothorax, bronchospasm, and aspiration pneumonitis. RESULTS: A total of 826 patients (mean age, 64 yr; 63% male) were included in the intention-to-treat analysis. A composite of pulmonary complications was less common in patients assigned to penehyclidine (18.9% [79 of 417]) than those receiving the placebo (26.4% [108 of 409]; relative risk, 0.72; 95% CI, 0.56 to 0.93; P = 0.010; number needed to treat, 13). Bronchospasm was less common in penehyclidine than placebo patients: 1.4% (6 of 417) versus 4.4% (18 of 409; relative risk, 0.327; 95% CI, 0.131 to 0.82; P = 0.011). None of the other individual pulmonary complications differed significantly. Peak airway pressures greater than 40 cm H2O were also less common in patients given penehyclidine: 1.9% (8 of 432) versus 4.9% (21 of 432; relative risk, 0.381; 95% CI, 0.171 to 0.85; P = 0.014). The incidence of other adverse events, including dry mouth and delirium, that were potentially related to penehyclidine inhalation did not differ between the groups. CONCLUSIONS: In high-risk patients having major upper-abdominal or noncardiac thoracic surgery, prophylactic penehyclidine inhalation reduced the incidence of pulmonary complications without provoking complications.


Asunto(s)
Espasmo Bronquial , Atelectasia Pulmonar , Espasmo Bronquial/inducido químicamente , Espasmo Bronquial/complicaciones , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/prevención & control , Atelectasia Pulmonar/complicaciones , Quinuclidinas/efectos adversos , Quinuclidinas/uso terapéutico
3.
J Neuroinflammation ; 17(1): 347, 2020 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-33213462

RESUMEN

BACKGROUND: The R1441G mutation in the leucine-rich repeat kinase 2 (LRRK2) gene results in late-onset Parkinson's disease (PD). Peripheral inflammation and gut microbiota are closely associated with the pathogenesis of PD. Chronic periodontitis is a common type of peripheral inflammation, which is associated with PD. Porphyromonas gingivalis (Pg), the most common bacterium causing chronic periodontitis, can cause alteration of gut microbiota. It is not known whether Pg-induced dysbiosis plays a role in the pathophysiology of PD. METHODS: In this study, live Pg were orally administrated to animals, three times a week for 1 month. Pg-derived lipopolysaccharide (LPS) was used to stimulate mononuclear cells in vitro. The effects of oral Pg administration on the gut and brain were evaluated through behaviors, morphology, and cytokine expression. RESULTS: Dopaminergic neurons in the substantia nigra were reduced, and activated microglial cells were increased in R1441G mice given oral Pg. In addition, an increase in mRNA expression of tumor necrosis factor (TNF-α) and interleukin-1ß (IL-1ß) as well as protein level of α-synuclein together with a decrease in zonula occludens-1 (Zo-1) was detected in the colon in Pg-treated R1441G mice. Furthermore, serum interleukin-17A (IL-17A) and brain IL-17 receptor A (IL-17RA) were increased in Pg-treated R1441G mice. CONCLUSIONS: These findings suggest that oral Pg-induced inflammation may play an important role in the pathophysiology of LRRK2-associated PD.


Asunto(s)
Microbioma Gastrointestinal/fisiología , Inmunidad/fisiología , Proteína 2 Quinasa Serina-Treonina Rica en Repeticiones de Leucina/inmunología , Microglía/inmunología , Enfermedades Neurodegenerativas/inmunología , Porphyromonas gingivalis/inmunología , Administración Oral , Animales , Infecciones por Bacteroidaceae/genética , Infecciones por Bacteroidaceae/inmunología , Células Cultivadas , Neuronas Dopaminérgicas/inmunología , Neuronas Dopaminérgicas/microbiología , Proteína 2 Quinasa Serina-Treonina Rica en Repeticiones de Leucina/genética , Ratones , Ratones Transgénicos , Microglía/microbiología , Enfermedades Neurodegenerativas/genética , Enfermedades Neurodegenerativas/microbiología , Permeabilidad , Sustancia Negra/inmunología , Sustancia Negra/microbiología
4.
J Cell Physiol ; 234(11): 21316-21330, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31081160

RESUMEN

Intramedullary stabilization is frequently used to treat long bone fractures. Since implant removal can become technically very challenging with the potential to cause further tissue damage, biodegradable materials are emerging as alternative options. Magnesium (Mg)-based biodegradable implants have a controllable degradation rate and good tissue compatibility, which makes them attractive for musculoskeletal research. Herein, the degradation of Mg and steel implants, the pathological characteristics and osteoblast differentiation in mice femora were examined. To investigate the molecular mechanism, we analyzed the differentially expressed long noncoding RNAs (lncRNAs) and messenger RNAs (mRNAs) in Mg-implanted or stain-steel-implanted callus tissues. lncRNA LOC103691336 was upregulated in Mg-implanted tissues and most relevant to BMPR2, a kinase receptor of BMPs with an established role in osteogenesis. The knockdown of LOC103691336 attenuated Mg-mediated osteogenic differentiation. Furthermore, miR-138-5p, previously reported to inhibit osteogenic differentiation, could bind to LOC103691336 and BMPR2 in bone marrow stromal cells (BMSCs). LOC103691336 competed with BMPR2 for miR-138-5p binding in BMSCs to attenuate the inhibitory effect of miR-138-5p on BMPR2 expression. Finally, the effect of LOC103691336 knockdown on Mg-mediated osteogenic differentiation could be attenuated by miR-138-5p inhibition. In conclusion, we provided a novel mechanism of Mg implants mediating the osteogenesis differentiation and demonstrated that Mg implants may be promising for improving fracture healing.


Asunto(s)
Curación de Fractura , Fijadores Internos , Magnesio/farmacología , Osteogénesis/fisiología , Animales , Células de la Médula Ósea/efectos de los fármacos , Células de la Médula Ósea/metabolismo , Receptores de Proteínas Morfogenéticas Óseas de Tipo II/metabolismo , Diferenciación Celular/fisiología , Modelos Animales de Enfermedad , Fracturas del Fémur/cirugía , Masculino , Células Madre Mesenquimatosas , MicroARNs/metabolismo , ARN Largo no Codificante/metabolismo , Ratas , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología , Acero Inoxidable/farmacología
5.
Biochem Biophys Res Commun ; 514(3): 618-624, 2019 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-31076107

RESUMEN

Magnesium (Mg) and its alloys as a type of different biodegradable materials have been used in the musculoskeletal field because of their excellent biocompatibility, biodegradability and mechanical properties similar to bone; besides, Mg could promote osteoblast differentiation in vitro and induce the formation of new bone in vivo. In the present study, we prepared the extracts of Mg-Zn-Mn alloy and examined their effects on the angiogenesis of human umbilical vein endothelial cells (HUVECs). In the present study, we prepared Mg-Zn-Mn alloy extracts of different concentrations and cultured HUVECs with these extracts. The DNA synthesis capacity, the cell viability, and the tube formation capacity of HUVECs could be significantly induced by 6.25% Mg alloy extract. In the meantime, the ratios of p-FGFR/FGFR, p-PI3K/PI3K, and p-AKT/AKT were significantly increased by 6.25% Mg alloy extract treatment, while decreased by FGFR/FGFR signaling pathway inhibitor BFJ398, indicating that 6.25% Mg alloy extract could promote the angiogenesis of HUVECs via activating FGF/FGFR signaling pathway. In conclusion, these data indicate that 6.25% Mg-Zn-Mn alloy extract induces the angiogenesis of HUVECs via FGF signaling pathway. Further in vivo experiments are needed to further confirm the present in vitro findings.


Asunto(s)
Aleaciones/farmacología , Factores de Crecimiento de Fibroblastos/metabolismo , Células Endoteliales de la Vena Umbilical Humana/fisiología , Neovascularización Fisiológica/efectos de los fármacos , Receptores de Factores de Crecimiento de Fibroblastos/metabolismo , Transducción de Señal , Proliferación Celular/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Humanos , Neovascularización Fisiológica/genética , Transducción de Señal/efectos de los fármacos
6.
Macromol Rapid Commun ; 40(4): e1800648, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30485580

RESUMEN

As one of the most important smart materials, fluorescent hydrogel actuators can produce both color and shape changes under external stimuli. In the present work, an effective approach to develop a novel fluorescent hydrogel actuator with pH and thermo dual responsiveness is proposed. Through incorporating pH-responsive perylene tetracarboxylic acid (PTCA), which is a typical fluorescent moiety with aggregation-caused quenching (ACQ) effect, into an anisotropic poly(N-isopropylacrylamide)-polyacrylamide (PNIPAm-PAAm) structure, the obtained hydrogel exhibits stable thermoresponsive shape deformation and switchable fluorescence performance upon a pH trigger. Therefore, fluorescence-quenching-based and actuation-based information can be revealed when exposed to UV light and immersed into warm water, respectively. Moreover, the thermoresponsive actuating behavior can be applied to further hide the fluorescence-quenching-based images. The present work may provide new insights into the design and preparation of novel stimuli-responsive hydrogel actuators.


Asunto(s)
Colorantes Fluorescentes/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Temperatura , Fluorescencia , Concentración de Iones de Hidrógeno , Tamaño de la Partícula , Propiedades de Superficie
7.
Sensors (Basel) ; 19(15)2019 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-31387246

RESUMEN

The development of sensors with high sensitivity, good flexibility, low cost, and capability of detecting multiple inputs is of great significance for wearable electronics. Herein, we report a napkin-based wearable capacitive sensor fabricated by a novel, low-cost, and facile strategy. The capacitive sensor is composed of two pieces of electrode plates manufactured by spontaneous assembly of silver nanowires (NWs) on a polydimethylsiloxane (PDMS)-patterned napkin. The sensor possesses high sensitivity (>7.492 kPa-1), low cost, and capability for simultaneous detection of multiple signals. We demonstrate that the capacitive sensor can be applied to identify a variety of human physiological signals, including finger motions, eye blinking, and minute wrist pulse. More interestingly, the capacitive sensor comfortably attached to the temple can simultaneously monitor eye blinking and blood pulse. The demonstrated sensor shows great prospects in the applications of human-machine interface, prosthetics, home-based healthcare, and flexible touch panels.


Asunto(s)
Monitoreo Fisiológico/métodos , Dispositivos Electrónicos Vestibles , Parpadeo/fisiología , Dimetilpolisiloxanos/química , Dedos/fisiología , Frecuencia Cardíaca/fisiología , Humanos , Monitoreo Fisiológico/instrumentación , Nanocables/química , Plata/química , Dispositivos Electrónicos Vestibles/economía
8.
Nanotechnology ; 29(42): 425603, 2018 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-30070976

RESUMEN

Wound infection caused by multiantibiotic-resistant bacteria has become a serious problem, and more effective antibacterial agents are required. Herein, we report the preparation of wound dressings using the biocompatible chitosan (CS) as a reducing and stabilizing agent in the synthesis of 2-mercapto-1-methylimidazole (MMT)-capped gold nanocomposites (CS-Au@MMT), with efficient antibacterial effects. The synergistic effects of AuNPs, MMT, and CS led to the disruption of bacterial membranes. After blending with gelatin, crosslinking with tannin acid, and freeze-drying, CS-gelatin (CS-Au@MMT/gelatin) dressing was prepared. It had good mechanical properties as well as efficient water absorption and retention capacities. It exhibited outstanding biocompatibility both in vitro and in a cell-based wound infection model. Moreover, the in vivo rabbit wound healing model revealed that the CS-Au@MMT/gelatin dressing possesses significant antibacterial potential against methicillin-resistant Staphylococcus aureus-associated wound infection. Therefore, the CS-Au@MMT/gelatin dressing described in this study may have huge potential in biomedical applications.


Asunto(s)
Antibacterianos/administración & dosificación , Vendajes , Nanopartículas del Metal/administración & dosificación , Infección de Heridas/tratamiento farmacológico , Animales , Antibacterianos/química , Materiales Biocompatibles , Línea Celular , Quitosano/química , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Gelatina/química , Oro/química , Oro/farmacología , Humanos , Nanopartículas del Metal/química , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica de Rastreo , Conejos , Infección de Heridas/microbiología
9.
Macromol Rapid Commun ; 39(12): e1800130, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29697163

RESUMEN

Realization of shape memory process in polymeric hydrogels at ambient condition is a significant development to shape memory materials. The sound understanding of the dynamic shape memory process is fundamentally important but limited. Here, a novel shape memory hydrogel with simultaneously switchable fluorescence behavior is developed. The hydrogel is prepared by incorporating a pH-responsive fluorescent molecule, perylene tetracarboxylic acid, into chitosan-based hydrogel, and the assembly and disassembly of chitosan chains into microcrystals upon the trigger of pH are applied as reversible crosslinks to achieve shape memory effect. Therefore, the formation and disassociation of microcrystalline chitosan, and the switchable fluorescence performance happen concurrently, which bring convenience to monitoring the shape memory process by fluorescent imaging. Moreover, the erasable fluorescence behavior also gives the hydrogel potential applications in information storage.


Asunto(s)
Quitosano/química , Fluorescencia , Hidrogeles/química , Perileno/análogos & derivados , Concentración de Iones de Hidrógeno , Espectroscopía de Resonancia Magnética , Estructura Molecular , Perileno/química , Polímeros/síntesis química , Polímeros/química
10.
J Chromatogr A ; 1721: 464861, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38564931

RESUMEN

The covalent attachment of polyoxometalates (POMs) to polymers has been developed as a strategic approach for the advancement of POM-based hybrid materials with versatile applications. In this study, we utilized thiol-maleimide Michael addition to investigate the kinetics and efficacy of the "one-to-one" conjugation between Keggin type POM and polystyrene. We explored the effects of solvent polarity, catalyst, molecular weight of PS and synthetic strategies on the reaction kinetics and efficiency, by means of reverse-phase high-performance liquid chromatography (RP-HPLC). A series of comparative analysis affirmed the superior efficiency of the one-pot method, particularly when facilitated by the addition of a high-polarity solvent and an excess of maleimide. These findings offer valuable insights into the intricate interplay between reaction conditions, kinetics, and selectivity in thiol-maleimide reactions of POMs and polymers. They hold profound implications for advancing the study of POM-based multifunctional materials and the synthesis of complex hybrid molecules.


Asunto(s)
Aniones , Polielectrolitos , Polímeros , Compuestos de Sulfhidrilo , Polímeros/química , Maleimidas/química , Solventes
11.
Chemosphere ; 355: 141834, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38565376

RESUMEN

Membrane fouling caused by the organics-coated particles was the main obstacle for the highly efficient shale gas produced water (SGPW) treatment and recycling. In this study, a novel hybrid electrocoagulation (EC) and E-peroxone process coupled with UF (ECP-UF) process was proposed to examine the efficacy and elucidate the mechanism for UF fouling mitigation in assisting SGPW reuse. Compared to the TMP (transmembrane pressure) increase of -15 kPa in the EC-UF process, TMP in ECP-UF system marginally increased to -1.4 kPa for 3 filtration cycles under the current density of 15 mA/cm2. Both the total fouling index and hydraulically irreversible fouling index of the ECP-UF process were significantly lower than those of EC-UF process. According to the extended Derjaguin-Landau-Verwey-Overbeek theory, the potential barriers was the highest for ECP-UF processes due to the substantial increase of the acid-base interaction energy in ECP-UF process, which was well consistent with the TMP and SEM results. Turbidity and TOC of ECP-UF process were 63.6% and 45.8% lower than those of EC-UF process, respectively. According to the MW distribution, the variations of compounds and their relative contents were probably due to the oxidation and decomposing products of the macromolecular organics. The number of aromatic compound decreased, while the number of open-chain compounds (i.e., alkenes, alkanes and alcohols) increased in the permeate of ECP-UF process. Notably, the substantial decrease in the relative abundance of di-phthalate compounds was attributed to the high reactivity of these compounds with ·OH. Mechanism study indicated that ECP could realize the simultaneous coagulation, H2O2 generation and activation by O3, facilitating the enhancement of ·OH and Alb production and therefore beneficial for the improved water quality and UF fouling mitigation. Therefore, the ECP-UF process emerges as a high-efficient and space-saving approach, yielding a synergistic effect in mitigating UF fouling for SGPW recycling.


Asunto(s)
Ultrafiltración , Purificación del Agua , Gas Natural , Peróxido de Hidrógeno , Membranas Artificiales , Purificación del Agua/métodos , Electrocoagulación
12.
Artículo en Inglés | MEDLINE | ID: mdl-38416616

RESUMEN

Most of the existing 3D talking face synthesis methods suffer from the lack of detailed facial expressions and realistic head poses, resulting in unsatisfactory experiences for users. In this paper, we propose a novel pose-aware 3D talking face synthesis method with a novel geometry-guided audio-vertices attention. To capture more detailed expression, such as the subtle nuances of mouth shape and eye movement, we propose to build hierarchical audio features including a global attribute feature and a series of vertex-wise local latent movement features. Then, in order to fully exploit the topology of facial models, we further propose a novel geometry-guided audio-vertices attention module to predict the displacement of each vertex by using vertex connectivity relations to take full advantage of the corresponding hierarchical audio features. Finally, to accomplish pose-aware animation, we expand the existing database with an additional pose attribute, and a novel pose estimation module is proposed by paying attention to the whole head model. Numerical experiments demonstrate the effectiveness of the proposed method on realistic expression and head movements against state-of-the-art methods.

13.
Colloids Surf B Biointerfaces ; 234: 113691, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38070369

RESUMEN

SEMA4D-modified titanium surfaces can indirectly regulate macrophages through endothelial cells to achieve an anti-inflammatory effect, which is beneficial for healing soft tissues around the gingival abutment. However, the mechanism of surface-induced cellular phenotypic changes in SEMA4D-modified titanium has not yet been elucidated. SEMA4D activates the RhoA signaling pathway in endothelial cells, which coordinates metabolism and cytoskeletal remodeling. This study hypothesized that endothelial cells inoculated on SEMA4D-modified titanium surfaces can direct M2 polarization of macrophages via metabolites. An indirect co-culture model of endothelial cells and macrophages was constructed in vitro, and specific inhibitors were employed. Subsequently, endothelial cell adhesion and migration, metabolic changes, Rho/ROCK1 expression, and inflammatory expression of macrophages were assessed via immunofluorescence microscopy, specific kits, qRT-PCR, and Western blotting. Moreover, an in vivo rat bilateral maxillary implant model was constructed to evaluate the soft tissue healing effect. The in vitro experiments showed that the SEMA4D group had stronger endothelial cell adhesion and migration, increased Rho/ROCK1 expression, and enhanced release of lactate. Additionally, decreased macrophage inflammatory expression was observed. In contrast, the inhibitor group partially suppressed lactate metabolism and motility, whereas increased inflammatory expression. The in vivo analyses indicated that the SEMA4D group had faster and better angiogenic and anti-inflammatory effects, especially in the early stage. In conclusion, via the Rho/ROCK1 signaling pathway, the SEMA4D-modified titanium surface promotes endothelial cell adhesion and migration and lactic acid release, then the paracrine lactic acid promotes the polarization of macrophages to M2, thus obtaining the dual effects of angiogenesis and anti-inflammation.


Asunto(s)
Antígenos CD , Células Endoteliales , Semaforinas , Titanio , Ratas , Animales , Titanio/farmacología , Ácido Láctico , Macrófagos , Antiinflamatorios
14.
Int J Biol Macromol ; 242(Pt 3): 124911, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37224899

RESUMEN

Skin wound healing in dynamic environments remains challenging. Conventional gels are not ideal dressing materials for wound healing due to difficulties in completely sealing wounds and the inability to deliver drugs quickly and precisely to the injury. To tackle these issues, we propose a multifunctional silk gel that rapidly forms strong adhesions to tissue, has excellent mechanical properties, and delivers growth factors to the wound. Specifically, the presence of Ca2+ in the silk protein leads to a solid adhesion to the wet tissue through a chelation reaction with water-trapping behavior; the integrated chitosan fabric and CaCO3 particles ensure enhanced mechanical strength of the silk gel for better adhesion and robustness during wound repair; and the preloaded growth factor further promoted wound healing. The results showed the adhesion and tensile breaking strength were as high as 93.79 kPa and 47.20 kPa, respectively. MSCCA@CaCO3-aFGF could remedy the wound model in 13 days, with 99.41 % wound shrinkage without severe inflammatory responses. Due to strong adhesion properties and mechanical strength, MSCCA@CaCO3-aFGF can be a promising alternative to conventional sutures and tissue closure staples for wound closure and healing. Therefore, MSCCA@CaCO3-aFGF is expected to be a strong candidate for the next generation of adhesives.


Asunto(s)
Seda , Adhesivos Tisulares , Adhesivos , Cicatrización de Heridas , Textiles , Geles , Adhesivos Tisulares/farmacología
15.
Polymers (Basel) ; 14(7)2022 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-35406238

RESUMEN

Application of ultra-high-performance concrete (UHPC) in joints can improve the impact resistance, crack resistance, and durability of structures. In this paper, the direct shear performance of ultra-high-performance concrete (UHPC) adhesive joints was experimentally studied. Twenty-four direct shear loading tests of UHPC adhesive joints were carried out considering different interface types and constraint states. The failure modes and load-slip curves of different interfaces were studied. Results indicated that passive confinement could enhance the strength and ductility of the interface; the average ultimate bearing capacity of the smooth, rough, grooved, and keyway specimens with passive restraint were, respectively, increased by 11.92%, 8.91%, 11.93%, and 17.766% compared with the unrestrained ones. The passive constraint force changes with the loading and finally tends to be stable. The epoxy adhesive has high reliability as a coating for the UHPC interface. The adhesive layer is not cracked before the failure of the specimen, which is also different from the common failure mode of adhesive joints. Failure of all specimens occurred in the UHPC layer, and the convex part of the groove interface shows the UHPC matrix peeling failure; the keyway interface is the shear damage of the key-tooth root, and the rest of the keyway showed UHPC surface peeling failure. According to the failure mode, the shear capacity of UHPC keyway adhesive joints under passive restraint is mainly provided by the shear resistance of key teeth, the friction force of the joint surface, and the bonding force of the UHPC surface. The friction coefficient was determined based on the test results, and the high-precision fitting formula between the shear strength of the UHPC surface and the passive constraint force was established. According to the Mohr stress circle theory, the proposed formula for direct shear strength of UHPC bonded joints under passive constraint was established. The average ratio of the proposed UHPC adhesive joint calculation formula to the test results was 0.99, and the standard deviation was 0.027.

16.
Acta Biomater ; 141: 454-465, 2022 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-34971787

RESUMEN

Magnesium (Mg) and some of its alloys are considered promising biodegradable metallic biomaterials for bone implant applications. The osteogenesis effect of Mg alloys is widely reported; however, the underlying mechanisms are still not clear. In this study, pure Mg, Mg-3Zn, and Mg-2Zn-1Mn were prepared, and their degradation behavior, biocompatibility, and osteogenesis effect were systematically assessed both in vitro and in vivo. Primary rat bone marrow-derived mesenchymal stem cells (BMSCs) were used to evaluate the biocompatibility of the prepared Mg alloys, and a rat femur fracture model was used to assess the stimulating effect of these alloys on bone-tissue formation. Mg-2Zn-1Mn showed higher corrosion resistance and more stable degradation behavior than pure Mg and Mg-3Zn. Extracts of the three materials showed significant stimulating effects on osteogenic differentiation of BMSCs along with non-cytotoxicity. Implantation of Mg-2Zn-1Mn wires into the femur of rats demonstrated superior histocompatibility, stable degradation, and notable promotion of osteogenesis without systemic toxicity. Moreover, the results of both in vitro and in vivo assessments demonstrated that bone morphogenetic proteins and fibroblast growth factor receptors are involved in the stimulating effect of Mg alloys. STATEMENT OF SIGNIFICANCE: This work reports the degradation behavior, biocompatibility, and osteogenic effect of pure Mg and Mg-3Zn and Mg-2Zn-1Mn alloys in both in vitro and in vivo conditions. Mg-2Zn-1Mn showed higher corrosion resistance and more stable degradation behavior than pure Mg and Mg-3Zn. The extracts of the three materials showed a significant stimulating effect on osteogenic differentiation of rat bone marrow-derived mesenchymal stem cells (BMSCs) along with non-cytotoxicity. Mg-2Zn-1Mn wires implanted into the femur of rats showed good histocompatibility, stable degradation, and notable promotion of osteogenesis without systemic toxicity. The results of the present study suggest that bone morphogenetic proteins (BMPs) and fibroblast growth factor receptors (FGFRs) are involved in the stimulating effect of Mg alloys on osteogenesis.


Asunto(s)
Aleaciones , Magnesio , Aleaciones/metabolismo , Aleaciones/farmacología , Animales , Magnesio/farmacología , Osteogénesis , Ratas , Receptores de Factores de Crecimiento de Fibroblastos
17.
Plant Sci ; 323: 111372, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35863557

RESUMEN

The dynamic alterations in cell wall (CW) biosynthesis play an essential role in physiological isolation during the plant somatic embryogenesis (SE). However, the mechanisms underlying the functions of cell wall-associated miRNAs (CW-miRNA) remain poorly understood in plant SE. Here, we have identified 36 distinct candidate miRNAs associated with CW biosynthesis from longan third-generation genome as well as miRNA transcriptome, and modified RLM-RACE validated four distinct miRNA, which specifically targeted four CW-related genes. More importantly, we found that the dlo-miR397a-antagomir significantly enhanced DlLAC7 expression and improved laccase activity. Interestingly, inhibition of dlo-miR397a increased CW lignin deposition and promoted the tightening of protodermal cell by miRNA-mimic technology during early SE. Moreover, overexpression of dlo-miR408-3p (dlo-miR408-3p-agomir) markedly decreased DlLAC12 expression. dlo-miR408-3p-agomir activated rapid cell division, thus promoting the globular embryo (GE) development, which might be due to high DNA synthesis activity in protoepidermal cells, rather than affecting lignin synthesis. The subcellular location also indicated that both DlLAC7 and DlLAC12 proteins were primarily localized in CW and regulated CW biosynthesis. Overall, our findings provided new insight on the molecular regulatory networks comprising various miRNAs associated with cell wall, and established that dlo-miR397a and dlo-miR408-3p played differential roles during early SE in longan. The findings also shed some light on the potential role of miRNA target DlLAC regulating in vivo embryonic development of plant.


Asunto(s)
MicroARNs , Pared Celular/metabolismo , Desarrollo Embrionario , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Lignina/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Técnicas de Embriogénesis Somática de Plantas , Sapindaceae
18.
Orthop Surg ; 14(3): 522-529, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35098677

RESUMEN

OBJECTIVE: To evaluate the placement feasibility and safety of the newly designed retropharyngeal reduction plate by cadaveric test and to perform morphometric trajectory analysis. METHODS: The five cadaveric specimens with intact atlantoaxial joint were enrolled in this study. They were used for simulating the placement process and evaluating the placement feasibility of the retropharyngeal reduction plate. The atlantoaxial dislocation (AAD) of five cadaveric specimens were obtained by proper external force after dissecting ligaments. The retropharyngeal reduction plate was placed on atlantoaxial joint of cadaveric specimens. The X-ray and three-dimensional (3D) spiral CT were used for evaluating the placement safety of retropharyngeal reduction plate. The DICOM data was obtained after 3D spiral CT scanning for the morphometric trajectory analysis. RESULTS: The reduction plates were successfully placed on the atlantoaxial joint of five cadaveric specimens through the retropharyngeal approach, respectively. The X-ray and 3D spiral CT showed the accurate screw implantation and satisfying plate placement. The length of the left/right atlas screw trajectory (L/RAT) was, respectively, 1.73 ± 0.01 cm (LAT) and 1.71 ± 0.02 cm (RAT). The length of odontoid screw trajectory (OST) was 1.38 ± 0.02 cm. The length of the left/right axis screw trajectory (L/RAXT) was, respectively, 1.67 ± 0.02 cm (LAXT) and 1.67 ± 0.01 cm (RAXT). There was no statistical significance between left side and right side in terms of AT and AXT (P > 0.05). The angles of atlas screw trajectory angle (ASTA), axis screw trajectory angle (AXSTA), and odontoid screw trajectory angle (OSTA) were 38.04° ± 2.03°, 56.92° ± 2.66°, and 34.78° ± 2.87°, respectively. CONCLUSION: The cadaveric test showed that the retropharyngeal reduction plate is feasible to place on the atlantoaxial joint, which is also a safe treatment choice for atlantoaxial dislocation. The meticulous preoperative planning of screw trajectory based on individual differences was also vital to using this technique.


Asunto(s)
Articulación Atlantoaxoidea , Luxaciones Articulares , Fusión Vertebral , Articulación Atlantoaxoidea/diagnóstico por imagen , Articulación Atlantoaxoidea/cirugía , Placas Óseas , Tornillos Óseos , Cadáver , Humanos , Luxaciones Articulares/diagnóstico por imagen , Luxaciones Articulares/cirugía , Tomografía Computarizada por Rayos X
19.
ACS Appl Mater Interfaces ; 13(14): 16048-16061, 2021 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-33813831

RESUMEN

Given that many people suffer from extensive skin damage, wound repair has drawn tremendous attention in research. Among the various assistant dressing materials that promote healing, a porcine acellular dermal matrix (PADM), as a skin substitute, can efficiently accelerate healing by promoting cell migration and proliferation. However, a simple, low-cost preparation process remains a challenge facing PADM development, particularly because of the inferior elasticity. To overcome these drawbacks, a CaCl2-ethanol-H2O solution (ternary solution) combined with an additional enzyme treatment was used to obtain a transparent, porous, and elastic PADM that retained the major extracellular matrix composition of the dermis. Our results indicated that alterations in the fiber organization and secondary structural changes in the collagen occurred after treatment. Furthermore, the in vivo wound healing and histological analyses clearly revealed an extremely expedited wound repair process following the application of the biocompatible PADM. In conclusion, this study provides new insights into the development of a transparent PADM with a porous structure and good elasticity that can be used as a skin substitute to accelerate the wound healing process. Moreover, this effective technique could potentially be used to extrapolate other decellularized materials in the future.


Asunto(s)
Dermis Acelular/metabolismo , Trasplante de Piel/métodos , Piel Artificial , Animales , Materiales Biocompatibles , Adhesión Celular , Matriz Extracelular/metabolismo , Humanos , Porcinos , Cicatrización de Heridas
20.
Colloids Surf B Biointerfaces ; 204: 111796, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33933879

RESUMEN

The efficiency of energy transfer from guanine nucleotide to terbium ion (Tb3+) is affected by the phosphate group significantly. Compared with the biomolecules 5'-GMP (guanosine monophosphate), guanosine diphosphate (GDP) exhibits better sensitize ability to Tb3+ ions luminescence. Assisted with the carboxycoumarin ligand, we synthesized a more stable optical Coumarin@GDP-Tb polymer with the characteristic emission peaks located on 440 nm and 545 nm in this work. The Coumarin@GDP-Tb polymer is not only rich in metal binding sites, but also maintains a moderate ionic binding force, which helps metal ions to bind or leave it easily. Experiment result shows that Coumarin@GDP-Tb polymer has the appropriate binding force for Fe2+ ions, which can be destroyed by sulfur ions (S2-) as the formation of FeS precipitation. Based on this, Coumarin@GDP-Tb was designed as the ratio fluorescence probe for sulfur ions detection, where the fluorescence at 545 nm can be selectively quenched by Fe2+ ions, while that at 440 nm was unaffected, in the presence of S2- ions, the quenched fluorescence can be recovered remarkably. With the increasing S2- ions from 0.1-45 µM, the ratio of fluorescence intensity at 545 nm to 440 nm (F545/F440) is linear to S2- concentration, and the detection limit of S2- was calculated to be 0.073 µM. Contrast to those fluorescence probes with single wavelength emission, Coumarin@GDP-Tb displays a comparable sensitivity, the introduced self-adjust wavelength improved the detection accuracy efficiently. The above 98.1 % recovery rates of S2- ions in the actual water sample demonstrated the practicability of Coumarin@GDP-Tb fluorescence probe.


Asunto(s)
Elementos de la Serie de los Lantanoides , Guanosina Difosfato , Ligandos , Polímeros , Sulfuros , Terbio
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