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1.
J Neurochem ; 168(7): 1265-1280, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38348636

RESUMEN

Orofacial neuropathic pain is a common symptom induced by orofacial nerve injury caused by a range of trauma or dental and maxillofacial procedures but lacks effective treatment. Circular RNAs (circRNAs) participate in the regulatory processes of neuropathic pain. Nevertheless, the biological roles of circRNAs in orofacial neuropathic pain remain unexplored. In this study, circRNA sequencing and Real-time quantitative polymerase chain reaction (RT-qPCR) were carried out. Notably, a novel circRNA named circ_lrrc49 was identified to be downregulated following chronic constriction injury of the infraorbital nerve (CCI-ION) in mice on day 14. Subsequent RNA Antisense Purification (RAP)-mass spectrometry and RNA immunoprecipitation found a direct interaction between circ_lrrc49 and increased sodium tolerance 1 homolog (Ist1). Western blot (WB) identified decreased expression of Ist1 on day 14 post-CCI-ION. Considering the known relationship between Ist1 and autophagy, LC3-II and p62 were detected to be upregulated, and an accumulation of autophagosomes were observed at the same time point. Besides, the knockdown of circ_lrrc49 by small interfering RNA (siRNA) reduced Ist1 expression, increased LC3-II, p62 levels and autophagosomes amount, and evoked orofacial mechanical hypersensitivity, which could be counteracted by the Ist1 overexpression. Similarly, the knockdown of Ist1 by siRNA also increased LC3-II and p62 levels and evoked orofacial mechanical hypersensitivity without influence on circ_lrrc49. Moreover, autophagy activation by rapamycin alleviated orofacial mechanical hypersensitivity evoked by CCI-ION or circ_lrrc49 knockdown. In conclusion, our data revealed the existence of a circ_lrrc49/Ist1/autophagy signaling axis contributing to the progression of orofacial neuropathic pain. These discoveries reveal the intricate molecular processes that drive orofacial neuropathic pain and identify circ_lrrc49 as a promising target for potential therapeutic interventions.


Asunto(s)
Autofagia , Regulación hacia Abajo , Ratones Endogámicos C57BL , Neuralgia , ARN Circular , Ganglio del Trigémino , Animales , Masculino , Ratones , Autofagia/fisiología , Neuralgia/metabolismo , ARN Circular/genética , ARN Circular/metabolismo , Ganglio del Trigémino/metabolismo , Proteínas Oncogénicas/genética , Proteínas Oncogénicas/metabolismo
2.
Angew Chem Int Ed Engl ; 63(13): e202318632, 2024 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-38327029

RESUMEN

Liposomes serve as promising and versatile vehicles for drug delivery. Tracking these nanosized vesicles, particularly in vivo, is crucial for understanding their pharmacokinetics. This study introduces the design and synthesis of three new conjugated electrolyte (CE) molecules, which emit in the second near-infrared window (NIR-II), facilitating deeper tissue penetration. Additionally, these CEs, acting as biomimetics of lipid bilayers, demonstrate superior compatibility with lipid membranes compared to commonly used carbocyanine dyes like DiR. To counteract the aggregation-caused quenching effect, CEs employ a twisted backbone, as such their fluorescence intensities can effectively enhance after a fluorophore multimerization strategy. Notably, a "passive" method was employed to integrate CEs into liposomes during the liposome formation, and membrane incorporation efficiency was significantly promoted to nearly 100%. To validate the in vivo tracking capability, the CE-containing liposomes were functionalized with cyclic arginine-glycine-aspartic acid (cRGD) peptides, serving as tumor-targeting ligands. Clear fluorescent images visualizing tumor site in living mice were captured by collecting the NIR-II emission. Uniquely, these CEs exhibit additional emission peak in visible region, enabling in vitro subcellular analysis using routine confocal microscopy. These results underscore the potential of CEs as a new-generation of membrane-targeting probes to facilitate the liposome-based medicine research.


Asunto(s)
Liposomas , Neoplasias , Ratones , Animales , Liposomas/química , Membrana Dobles de Lípidos/química , Biomimética , Sistemas de Liberación de Medicamentos , Colorantes Fluorescentes/química
3.
J Oral Rehabil ; 49(2): 195-206, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34714950

RESUMEN

BACKGROUND: Orofacial ectopic pain induced by trigeminal nerve injury is a serious complication of dental treatment. C-X-C motif chemokine ligand 1 (CXCL1) and its primary receptor C-X-C motif chemokine receptor 2 (CXCR2) contribute to the development and maintenance of neuropathic pain in the spinal nervous system, but their roles in trigeminal neuropathic sensation are still poorly understood. OBJECTIVES: This study aimed to investigate the exact role of CXCL1 and CXCR2 in the regulation of orofacial ectopic mechanical allodynia and their potential downstream mechanisms in the trigeminal ganglion (TG). METHODS: The head withdrawal threshold (HWT) of C57BL/6 mice was evaluated after inferior alveolar nerve (IAN) transection (IANX). Then, the distribution and expression of CXCL1 and CXCR2, and their potential downstream mechanisms in the TG were further measured using immunohistochemistry, real-time reverse transcription-quantitative polymerase chain reaction and Western blotting. Moreover, the effect of SB225002 (an inhibitor of CXCR2) on mechanical allodynia was examined. The data were analysed using the Student's t test and a analysis of variance (ANOVA). RESULTS: IANX triggered persistent (>21 days) mechanical allodynia and upregulation of CXCL1 and CXCR2 in the TG. In addition, exogenous CXCL1 also lowered the HWT, which was alleviated by CXCR2 and protein kinase C (PKC) antagonists (p < .05). In addition, IANX increased the phosphorylated PKC (p-PKC) levels and decreased the expression of voltage-gated potassium channels (Kv), and these effects were reversed by inhibition of CXCR2 (p < .05). CONCLUSION: Our results demonstrated that CXCR2 participated in orofacial ectopic mechanical allodynia via downregulation of Kv1.4 and Kv1.1 through the PKC signalling pathway. This mechanism may be a potential target in developing a treatment strategy for ectopic orofacial pain.


Asunto(s)
Hiperalgesia , Ganglio del Trigémino , Animales , Quimiocina CXCL1 , Ligandos , Ratones , Ratones Endogámicos C57BL , Receptores de Quimiocina , Receptores de Interleucina-8B
4.
J Minim Access Surg ; 18(3): 450-458, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35708390

RESUMEN

Aim: To evaluate the protective effect of axillary channel-assisted (ACA) transoral endoscopic thyroidectomy vestibular approach on mental nerve. Materials and Methods: From August 2018 to December 2020, 126 cases of thyroid micro-carcinoma patients who underwent endoscopic thyroidectomy were recruited retrospectively. Of those, 74 cases were performed with ACA trans-oral endoscopic thyroidectomy vestibular approach (ACA_TOETVA) (V and A group), 52 cases received standard TOETVA (V group). On postoperative day 1 (POD1), nylon monofilament test and numbness visual analogue scale score were conducted to evaluate the severity of numbness within the mental area, facial expression was tested to determine the motor function of lower mandible and the thickness of cutaneous and subcutaneous layers was measured with ultrasound. The other observation parameters including the time for operation and intraoperative blood loss were carefully collected. Results: On POD1, nylon monofilament test showed that scores in the V and A group (2.9 ± 0.3) were significantly higher than V group (1.7 ± 0.5), P < 0.01, u = 254. The completion percentage of facial expression in the V and A group was 90.5% (67/74) and significantly higher than in V group (21.2%, 11/52), P < 0.01, χ2 = 62.35. The thickness increment of cutaneous and subcutaneous layer was 2.2 ± 1.2 mm in the V and A group, which was significantly less than in the V group (4.0 ± 1.2 mm), P < 0.01, u = 605. Compared with V group, the operation time (113.4 ± 22.3 min vs. 127.7 ± 25.6 min, u = 1262) and intraoperative blood loss (43.5 ± 13.4 ml vs. 51.0 ± 14.1 ml, u = 1355) were also significantly less in the V and A group. Conclusions: The ACA transoral endoscopic thyroidectomy possesses the protective effect on mental nerve and motor function of lower mandible and facilitates the operative procedures of TOETVA.

5.
Molecules ; 26(21)2021 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-34770854

RESUMEN

Lactic acid (LA) is an important organic acid with broad industrial applications. Considered as an environmentally friendly alternative to petroleum-based plastic with a wide range of applications, polylactic acid has generated a great deal of interest and therefore the demand for optically pure l- or d-lactic acid has increased accordingly. Microbial fermentation is the industrial route for LA production. LA bacteria and certain genetic engineering bacteria are widely used for LA production. Although some fungi, such as Saccharomyces cerevisiae, are not natural LA producers, they have recently received increased attention for LA production because of their acid tolerance. The main challenge for LA bioproduction is the high cost of substrates. The development of LA production from cost-effective biomasses is a potential solution to reduce the cost of LA production. This review examined and discussed recent progress in optically pure l-lactic acid and optically pure d-lactic acid fermentation. The utilization of inexpensive substrates is also focused on. Additionally, for PLA production, a complete biological process by one-step fermentation from renewable resources is also currently being developed by metabolically engineered bacteria. We also summarize the strategies and procedures for metabolically engineering microorganisms producing PLA. In addition, there exists some challenges to efficiently produce PLA, therefore strategies to overcome these challenges through metabolic engineering combined with enzyme engineering are also discussed.


Asunto(s)
Desarrollo de Medicamentos , Ácido Láctico/metabolismo , Poliésteres/metabolismo , Ácido Láctico/química , Ingeniería Metabólica , Poliésteres/química
6.
Med Sci Monit ; 26: e924666, 2020 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-32894745

RESUMEN

BACKGROUND Bone tissue engineering has been proven to be an appropriate approach for treating bone defects. This study aimed to investigate the effects and mechanism of a composite tissue engineered bone material consisting of bone mesenchymal stem cells (BMSCs), bone morphogenetic protein (BMP9) gene lentiviral vector, and P3HB4HB thermogel (BMSCs-LV-BMP9-P3HB4HB) on calvarial skull defects in rats. MATERIAL AND METHODS LV-BMP9 viral vector was structured and infected to BMSCs-P3HB4HB composite scaffold, which was named as BMSCs-P3HB4HB composite bone repair material. Adipogenic differentiation was determined by oil-red O (ORO) and alkaline phosphatase (ALP) staining. Osteogenic differentiation was measured using Alizarin red staining. Cell viability was examined using Cell-Counting Kit-8 (CCK-8) assay. Protein expression of osteogenic factors, including BMP9, runt-related transcription factor 2 (RUNX2), osteocalcin (OCN), osteopontin (OPN), and osterix (OSX), was detected with Western blot assay and immunohistochemistry. mRNA of these osteogenic factors was examined by RT-PCR. Histological changes were examined with hematoxylin and eosin (H&E) and Masson's trichrome staining. Bone repair was measured using micro-computed tomography (micro-CT). RESULTS BMSCs and LV-BMP9-infected BMSCs demonstrated adipogenic and osteogenic differentiation potential. BMSCs-P3HB4HB scaffold demonstrated good cell-tissue compatibility. BMSCs-LV-BMP9-P3HB4HB exhibited significantly higher osteogenic ability and cell viability of BMSCs compared to BMSCs-LV-P3HB4HB (p<0.05). BMSCs-LV-BMP9-P3HB4HB significantly promoted osteogenic factors (RUNX2, OCN, OPN, and OSX) expression compared to the BMSCs-LV-P3HB4HB group (p<0.05) in both BMSCs and in calvarial defect rats. BMSCs-LV-BMP9-P3HB4HB demonstrated stronger repair ability. BMSCs-LV-BMP9-P3HB4HB significantly alleviated pathological injury and increased collagen fiber production compared to the BMSCs-LV-P3HB4HB group (p<0.05). CONCLUSIONS BMSCs-LV-BMP9-P3HB4HB composite bone repair material can effectively repair injured skull tissues of calvarial defect rats through triggering osteogenic factors expression. The present generated bone repair material may have applications in tissue engineering in regeneration of bone defects.


Asunto(s)
Sustitutos de Huesos , Factor 2 de Diferenciación de Crecimiento/metabolismo , Células Madre Mesenquimatosas , Ingeniería de Tejidos/métodos , Andamios del Tejido , Animales , Regeneración Ósea , Sustitutos de Huesos/química , Geles , Vectores Genéticos , Lentivirus , Osteogénesis , Poliésteres , Ratas , Ratas Sprague-Dawley , Cráneo , Andamios del Tejido/química
7.
Phys Chem Chem Phys ; 21(22): 11903-11915, 2019 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-31125035

RESUMEN

Biobutanol production by fermentation is potentially a sustainable alternative to butanol production from fossil fuels. However, the toxicity of butanol to fermentative bacteria, resulting largely from cell membrane fluidization, limits production titers and is a major factor limiting the uptake of the technology. Here, studies were undertaken, in vitro and in silico, on the butanol effects on a representative bacterial (i.e. Escherichia coli) inner cell membrane. A critical butanol : lipid ratio for stability of 2 : 1 was observed, computationally, consistent with complete interdigitation. However, at this ratio the bilayer was ∼20% thicker than for full interdigitation. Furthermore, butanol intercalation induced acyl chain bending and increased disorder, measured as a 27% lateral diffusivity increase experimentally in a supported lipid bilayer. There was also a monophasic Tm reduction in butanol-treated large unilamellar vesicles. Both behaviours are inconsistent with an interdigitated gel. Butanol thus causes only partial interdigitation at physiological temperatures, due to butanol accumulating at the phospholipid headgroups. Acyl tail disordering (i.e. splaying and bending) fills the subsequent voids. Finally, butanol short-circuits the bilayer and creates a coupled system where interdigitated and splayed phospholipids coexist. These findings will inform the design of strategies targeting bilayer stability for increasing biobutanol production titers.


Asunto(s)
1-Butanol/química , Membrana Celular/química , Membrana Dobles de Lípidos/química , Escherichia coli/química , Simulación de Dinámica Molecular , Fosfatidiletanolaminas/química , Fosfatidilgliceroles/química , Temperatura de Transición , Liposomas Unilamelares/química
8.
Macromol Rapid Commun ; 38(14)2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28485819

RESUMEN

Variations in the open-circuit voltage (Voc ) of ternary organic solar cells are systematically investigated. The initial study of these devices consists of two electron-donating oligomers, S2 (two units) and S7 (seven units), and the electron-accepting [6,6]-phenyl C71 butyric acid methyl ester (PC71 BM) and reveals that the Voc is continuously tunable due to the changing energy of the charge transfer state (Ect ) of the active layers. Further investigation suggests that Voc is also continuously tunable upon change in Ect in a ternary blend system that consists of S2 and its corresponding polymer (P11):PC71 BM. It is interesting to note that higher power conversion efficiencies can be obtained for both S2:S7:PC71 BM and S2:P11:PC71 BM ternary systems compared with their binary systems, which can be ascribed to an improved Voc due to the higher Ect and an improved fill factor due to the improved film morphology upon the incorporation of S2. These findings provide a new guideline for the future design of conjugated polymers for achieving higher performance of ternary organic solar cells.


Asunto(s)
Fulerenos/química , Polímeros/química , Energía Solar , Fotoquímica , Luz Solar
9.
Int J Mol Sci ; 17(6)2016 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-27338359

RESUMEN

Plant-growth-promoting rhizobacteria can improve plant growth, development, and stress adaptation. However, the underlying mechanisms are still largely unclear. We investigated the effects of Bacillus megaterium BOFC15 on Arabidopsis plants. BOFC15 produced and secreted spermidine (Spd), a type of polyamine (PA) that plays an important role in plant growth. Moreover, BOFC15 induced changes in the cellular PAs of plants that promoted an increase of free Spd and spermine levels. However, these effects were remarkably abolished by the addition of dicyclohexylamine (DCHA), a Spd biosynthetic inhibitor. Additionally, the inoculation with BOFC15 remarkably increased plant biomass, improved root system architecture, and augmented photosynthetic capacity. Inoculated plants also displayed stronger ability to tolerate drought stress than non-inoculated (control) plants. Abscisic acid (ABA) content was notably higher in the inoculated plants than in the control plants under drought stress and polyethylene glycol (PEG)-induced stress conditions. However, the BOFC15-induced ABA synthesis was markedly inhibited by DCHA. Thus, microbial Spd participated in the modulation of the ABA levels. The Spd-producing BOFC15 improved plant drought tolerance, which was associated with altered cellular ABA levels and activated adaptive responses.


Asunto(s)
Arabidopsis/microbiología , Bacillus megaterium/fisiología , Rizoma/microbiología , Espermidina/metabolismo , Estrés Fisiológico , Ácido Abscísico/metabolismo , Arabidopsis/crecimiento & desarrollo , Arabidopsis/metabolismo , Bacillus megaterium/patogenicidad , Biomasa , Sequías , Fotosíntesis , Polietilenglicoles/toxicidad
10.
Cell Biol Int ; 39(1): 35-43, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25044369

RESUMEN

The Wnt/ß-catenin signalling pathway contributes to the maintenance of pluripotency and partial reprogramming of stem cells. Postnatal neural crest cells (NCCs) can differentiate into odontoblast-like cells due to their multi-potential property, but further endeavors need to be made to promote odontogenic differentiation of hair follicle neural crest cells (hfNCCs). This study investigated whether the Wnt pathway activator lithium chloride (LiCl) promotes odontoblast differentiation of hfNCCs. Change of proliferation, ß-catenin and pluripotency markers of hfNCCs were examined after treatment with LiCl. An in vitro odontoblast differentiation model of hfNCCs was built using dental cell conditioned media (DC-CM). The effects of LiCl on odontoblast differentiation of hfNCCs showed that proliferation and expression of ß-catenin in the cytosolic and nuclear compartments were increased in the LiCl-treated hfNCCs, and the pluripotency marks, Oct4, Klf4, Sox2 and Nanog, were more highly expressed in the LiCl-treated group than in the control group. The odontoblast markers such as DSP, DMP1 and Runx2, could be detected in hfNCCs induced by DC-CM, but in LiCl -treated group all three markers had stronger expression. Expression of ß-catenin in the nuclear of LiCl-treated hfNCCs induced by DC-CM was higher than in the other groups. The data indicate that the Wnt pathway activator LiCl can promote proliferation and odontoblast differentiation of hfNCCs, and chemical approaches are of benefit in obtaining more desirable seed cell types for cell-based therapies.


Asunto(s)
Diferenciación Celular/efectos de los fármacos , Cloruro de Litio/farmacología , Odontoblastos/citología , Vía de Señalización Wnt/efectos de los fármacos , Animales , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Subunidad alfa 1 del Factor de Unión al Sitio Principal/metabolismo , Medios de Cultivo Condicionados/farmacología , Desmoplaquinas/metabolismo , Proteínas de la Matriz Extracelular/metabolismo , Folículo Piloso/citología , Proteínas de Homeodominio/metabolismo , Factor 4 Similar a Kruppel , Factores de Transcripción de Tipo Kruppel/metabolismo , Ratones , Ratones Endogámicos ICR , Cresta Neural/citología , Cresta Neural/efectos de los fármacos , Cresta Neural/metabolismo , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , Odontoblastos/metabolismo , Factores de Transcripción SOXB1/metabolismo , Regulación hacia Arriba/efectos de los fármacos , beta Catenina/metabolismo
11.
Nano Lett ; 13(5): 2078-85, 2013 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-23570565

RESUMEN

We have developed a supercapacitor electrode composed of well-aligned CoO nanowire array grown on 3D nickel foam with polypyrrole (PPy) uniformly immobilized onto or firmly anchored to each nanowire surface to boost the pseudocapacitive performance. The electrode architecture takes advantage of the high electrochemical activity from both the CoO and PPy, the high electronic conductivity of PPy, and the short ion diffusion pathway in ordered mesoporous nanowires. These merits together with the elegant synergy between CoO and PPy lead to a high specific capacitance of 2223 F g(-1) approaching the theoretical value, good rate capability, and cycling stability (99.8% capacitance retention after 2000 cycles). An aqueous asymmetric supercapacitor device with a maximum voltage of 1.8 V fabricated by using our hybrid array as the positive electrode and activated carbon film as the negative electrode has demonstrated high energy density (~43.5 Wh kg(-1)), high power density (~5500 W kg(-1) at 11.8 Wh kg(-1)) and outstanding cycleability (~20,000 times). After charging for only ~10 s, two such 4 cm(2) asymmetric supercapacitors connected in series can efficiently power 5 mm diameter red, yellow, and green round LED indicators (lasting for 1 h for red LED) and drive a mini 130 rotation-motor robustly.


Asunto(s)
Cobalto/química , Nanocables/química , Óxidos/química , Polímeros/química , Pirroles/química , Electrodos , Níquel/química , Tamaño de la Partícula , Propiedades de Superficie , Agua/química
12.
Zhongguo Gu Shang ; 37(4): 352-7, 2024 Apr 25.
Artículo en Zh | MEDLINE | ID: mdl-38664204

RESUMEN

OBJECTIVE: To compare the clinical outcomes of using elastic intramedullary nail and plate to fix fibular fracture. METHODS: The 60 patients with tibiofibular fractures admitted from January 2015 to December 2022 were divided into two groups:intramedullary nail group and plate group, 30 cases each, intramedullary nail group was treated with elastic intramedullary nail fixation group, plate group was treated with steel plate and screw fixation group. Intramedullary nail group, there were 18 males and 12 females, aged from 22 to 75 years old with an average of (39.4±9.8) years old, including 24 cases of traffic accidents injury, 6 cases of falling injury, 23 cases of closed fractures, 7 cases of open fractures. Steel plate group, there were 15 males and 15 females, aged from 24 to 78 years old with an average of (38.6±10.2) years old. The 22 cases were injured by traffic accident, 8 cases were injured by falling. The 24 cases were closed fractures and 6 cases were open fractures. The operation time, intraoperative bleeding, American Orthopedic Foot and Ankle Society (AOFAS) ankle and hind foot scores, clinical healing time of fibula and the incidence of wound complications were compared between the two groups. RESULTS: The patients in both groups were followed up for 6 to 21 months, with an average of (14.0±2.8) months. Compared with plate group, intramedullary nail group had shorter operative time, less bleeding, shorter clinical healing time of fibula, and lower infection rate of incision, and the difference was statistically significant (P<0.05). There were 2 cases of delayed healing in intramedullary nail group, 1 case of nonunion in plate group, and 2 cases of delayed healing in plate group, and there was no statistically significant difference between the two groups (P>0.05). In the last follow-up, according to the AOFAS scoring standard, the ankle function in intramedullary nail group was excellent in 17 cases, good in 12 cases, fair in 1 case, with an average of (88.33±4.57) points, while in plate group, excellent in 16 cases, good in 10 cases, fair in 4 cases, with an average of (87.00±4.14) points;There was no statistical difference between the two groups (P>0.05). CONCLUSION: Elastic intramedullary nail has the advantages of short operation time, less intraoperative bleeding, short fracture healing time and less incision complications in the treatment of fibular fracture, which is worthy of clinical application.


Asunto(s)
Clavos Ortopédicos , Placas Óseas , Peroné , Fracturas de la Tibia , Humanos , Masculino , Femenino , Persona de Mediana Edad , Adulto , Anciano , Peroné/lesiones , Peroné/cirugía , Fracturas de la Tibia/cirugía , Titanio , Fijación Intramedular de Fracturas/métodos , Fijación Intramedular de Fracturas/instrumentación , Adulto Joven , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Fijación Interna de Fracturas/métodos , Fijación Interna de Fracturas/instrumentación , Acero
13.
Int J Biol Macromol ; 253(Pt 4): 127079, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37769761

RESUMEN

Poly(lactic acid) (PLA) is one of the most promising bio-based polyester with great potential to replace for the petroleum-based polymers, which can significantly reduce greenhouse gas emissions. However, the inherent brittleness of PLA seriously restricts its broad applications. Herein, PLA/poly(ε-caprolactone) (PCL)/ethylene methyl acrylate-glycidyl methacrylate (EMA-GMA) ternary blends with different phase structures were prepared through reactive blending. The reactions between the epoxy groups of EMA-GMA and the carboxyl and hydroxyl end groups of PLA and PCL and were evidenced from the Fourier transform infrared spectroscopy, dynamic mechanical analysis and rheological results. The atomic force microscopy (AFM) images clearly revealed the formation of stack structure of the PCL and EMA-GMA minor phases in PLA/PCL/EMA-GMA (80/15/5) blend, and core-shell particle structures in PLA/PCL/EMA-GMA (80/10/10) and (80/5/15) blends. In terms of elongation at break and impact toughness, PLA/PCL/EMA-GMA (80/5/15) blend presents the best properties among all the compositions. Moreover, it also behaved excellent stiffness-toughness balance. The toughening mechanism can be ascribed to the formation of core-shell structure and the existence of interfacial adhesion in the ternary blends. This work can provide guide for the preparation and design of PLA-based partially renewable supertough materials that can compete with conventional petro-derived plastics.


Asunto(s)
Poliésteres , Polímeros , Poliésteres/química , Polímeros/química , Metacrilatos
14.
Anthropol Anz ; 80(4): 471-480, 2023 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-36519967

RESUMEN

Delayed closure of the anterior fontanelle is often associated with various disorders. However, the phenomenon might be a normal variation. In this study, the anterior fontanelle was investigated in children from the Iron Age Zaghunluq cemetery in Xinjiang, northwestern China. Age at death was estimated by tooth development/eruption in the children. The anterior fontanelle was visually assessed for delayed fusion. Three out of nine children aged between 3-6 years old from the cemetery had signs of open anterior fontanelle. However, there were no signs of craniofacial pathology or developmental disruption. Delayed closure of the anterior fontanelle might have been a norm in the Iron Age Zaghunluq population. However, it is impossible to determine the reasons behind the high prevalence of delayed AF closure at Zaghunluq. Additional studies are warranted to determine whether this phenomenon is population specific, or diet specific, or just an individual variation.


Asunto(s)
Fontanelas Craneales , Humanos , Niño , Preescolar , China/epidemiología
15.
Zhonghua Yi Xue Za Zhi ; 92(23): 1630-4, 2012 Jun 19.
Artículo en Zh | MEDLINE | ID: mdl-22944134

RESUMEN

OBJECTIVE: To explore the roles of nano-hydroxyapatite/collagen/PLA (nHAC/PLA) plus endothelial progenitor cells (EPCs) in repairing segmental bone defects of rabbit radius and enhancing angiogenesis and new bone formation. METHODS: EPCs isolated from New Zealand white rabbit bone marrow were cultured, identified and seeded into nHAC/PLA scaffolds. And the growth of EPCs in scaffolds was observed under scanning electron microscopy (SEM). Thirty-six were randomly divided into 3 groups to establish segmental bone defect models in radii. Two groups were implanted with EPCs/scaffolds constructs (group A, n = 16) and scaffolds alone (group B, n = 16) respectively. The remaining four rabbits were used as negative control (group C) and nothing was implanted. Animals were sacrificed at different timepoints and radii harvested to undergo radiological examination, histological examination and microvessle density test. RESULTS: These cells isolated from bone marrow were confirmed as EPCs. SEM showed that EPCs attached to the nHAC/PLA scaffolds, grew and proliferated well. Animal experiments revealed that radiological scores (5w: 2.25 ± 0.50 vs 1.00 ± 0.00; 10w: 2.75 ± 0.50 vs 1.75 ± 0.50; 15w: 4.25 ± 0.50 vs 3.0 ± 0.0; each P < 0.05), percentage of new bone formation area in bone defect regions (5w: 29.0% ± 3.5% vs 8.1% ± 0.8%; 10w: 63.4% ± 5.5% vs 16.6% ± 1.3%; 15w: 96.0% ± 4.3% vs 34.0% ± 6.6%; each P < 0.05) and microvessel density (2w: 13.5 ± 0.9 vs 4.3 ± 1.0; 5w:9.8 ± 0.7 vs 4.8 ± 0.3; 10w: 7.0 ± 0.4 vs 4.5 ± 0.4; each P < 0.05) in group A were significantly higher than those in group B. No new bone formation occurred in group C. CONCLUSION: The composite structure of EPCs-nHAC/PLA can enhance angiogenesis and new bone formation in segmental bone defects in rabbit radii. It may become a potential candidate of promoting revascularization of tissue engineering bone and repairing large bone defects.


Asunto(s)
Regeneración Ósea , Colágeno , Durapatita , Células Endoteliales/citología , Células Madre/citología , Ingeniería de Tejidos/métodos , Andamios del Tejido , Animales , Materiales Biocompatibles , Ácido Láctico , Osteogénesis , Polímeros , Conejos
16.
Eur J Pharmacol ; 931: 175211, 2022 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-35981606

RESUMEN

Trigeminal nerve injury is a common complication of various dental and oral procedures, which could induce trigeminal neuropathic pain but lack effective treatments. P2 purinergic receptors have emerged as novel therapeutic targets for such pain. Recent reports implied that the P2Y14 receptor (P2Y14R) was activated and promoted orofacial inflammatory pain and migraine. However, the role and mechanism of P2Y14R in trigeminal neuropathic pain remain unknown. We induced an orofacial neuropathic pain model by chronic constriction injury of the infraorbital nerve (CCI-ION). Von-Frey tests showed that CCI-ION induced orofacial mechanical hypersensitivity. The increased activating transcription factor 3 (ATF3) expression in the trigeminal ganglion (TG) measured by immunofluorescence confirmed trigeminal nerve injury. Immunofluorescence showed that P2Y14R was expressed in trigeminal ganglion neurons (TGNs) and satellite glial cells (SGCs). RT-qPCR and Western blot identified increased expression of P2Y14R in TG after CCI-ION. CCI-ION also upregulated interleukin-1ß (IL-1ß), interleukin-6 (IL-6), C-C motif chemokine ligand 2 (CCL2), and tumor necrosis factor-α (TNF-α) in TG. Notably, CCI-ION-induced mechanical hypersensitivity and pro-inflammatory cytokines production were decreased by a P2Y14R antagonist (PPTN). Trigeminal administration of P2Y14R agonist (UDP-glucose) evoked orofacial mechanical hypersensitivity and increased pro-inflammatory cytokines above in TG. Furthermore, CCI-ION induced activation of extracellular signal-regulated kinase 1/2 (ERK1/2) and p38 in TG, which also were reduced by PPTN. The inhibitors of ERK1/2 (U0126) and p38 (SB203580) decreased these upregulated pro-inflammatory cytokines after CCI-ION. Collectively, this study revealed that P2Y14R in TG contributed to trigeminal neuropathic pain via ERK- and p38-dependent neuroinflammation. Thus, P2Y14R may be a potential drug target against trigeminal neuropathic pain.


Asunto(s)
Neuralgia , Traumatismos del Nervio Trigémino , Animales , Dolor Facial/metabolismo , Hiperalgesia/metabolismo , Ratones , Neuralgia/etiología , Neuralgia/metabolismo , Ratas , Ratas Sprague-Dawley , Ganglio del Trigémino , Traumatismos del Nervio Trigémino/metabolismo
17.
ACS Sens ; 4(6): 1524-1533, 2019 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-31132253

RESUMEN

This paper describes the detection and discrimination of volatile organic compounds (VOCs) using an e-nose system based on a multiparameter virtual sensor array (VSA), which consists of a single-chip temperature-compensated film bulk acoustic wave resonator (TC-FBAR) coated with 20-bilayer self-assembled poly(sodium 4-styrenesulfonate)/poly(diallyldimethylammonium chloride) thin films. The high-frequency and microscale FBAR multiparameter VSA was realized by temperature modulation, which can greatly reduce the cost and complexity compared to those of a traditional e-nose system and can allow it to operate at different temperatures. The discrimination effect depends on the synergy of temperature modulation and the sensing material. For proof-of-concept validation purposes, the TC-FBAR was exposed to six different VOC vapors at six different gas partial pressures by real-time VOC static detection and dynamic detection. The resulting frequency shifts and impedance responses were measured at different temperatures and evaluated using principal component analysis and linear discriminant analysis, which revealed that all analytes can be distinguished and classified with more than 97% accuracy. To the best of our knowledge, this report is the first on an FBAR multiparameter VSA based on temperature modulation, and the proposed novel VSA shows great potential as a compact and promising e-nose system integrated in commercial electronic products.


Asunto(s)
Nariz Electrónica , Membranas Artificiales , Procedimientos Analíticos en Microchip/métodos , Polietilenos/química , Polímeros/química , Compuestos de Amonio Cuaternario/química , Ácidos Sulfónicos/química , Compuestos Orgánicos Volátiles/análisis , Análisis Discriminante , Diseño de Equipo , Análisis de Componente Principal , Prueba de Estudio Conceptual , Sonido , Temperatura
18.
mSystems ; 4(6)2019 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-31690590

RESUMEN

Globally, dental caries is the most prevalent chronic oral disease and affects roughly half of all children. The aim of this report was to use metagenomic analyses to investigate the relationship between the oral microbiome and caries in preschool children. A total of 25 preschoolers, aged 3 to 5 years old with severe early childhood caries (ECC), and 19 age-matched, caries-free children as controls were recruited. Saliva samples were collected from the participants and were subjected to metagenomic analyses, whereby the oral microbial communities were investigated. The metagenomic analyses revealed substantial microbiota differences between the two groups, indicating apparent shifts of the oral microbiome present in the ECC group. At the species level, the ECC-enriched microbes included Prevotella amnii, Shuttleworthia satelles, Olsenella uli, and Anaeroglobus geminatus Interestingly, Actinomyces odontolyticus and Actinomyces graevenitzii exhibited apparent differences at the strain level but not the species level between the ECC and control groups. Functional examination showed that the ECC group displayed extensive alterations in metabolic genes/pathways/modules, including enriched functions in sugar metabolism. Finally, an SVM (support vector machine) classifier comprising seven species was developed and generated a moderately good performance in predicting caries onset (area under the receiver operating characteristic curve [AUC] = 78.33%). Together, these findings indicate that caries is associated with considerable changes in the oral microbiome, some of which can potentially be exploited as therapeutic targets or diagnostic markers. (This study has been registered at ClinicalTrials.gov under registration no. NCT02341352.)IMPORTANCE Dental caries is a highly prevalent oral disease that can lead to severe dental damage and may greatly compromise the quality of life of the affected individuals. Previous studies, including those based on 16S rRNA gene, have revealed that the oral microbiota plays a prominent role in development of the disease. But the approach of those studies was limited in analyzing several key microbiome traits, including species- or strain-level composition and functional profile. Here, we performed metagenomic analyses for a cohort of preschool children with or without caries. Our results showed that caries was associated with extensive microbiota differences at various taxonomic and functional levels. Some caries-associated species had not been previously reported, some of which may have significant clinical implications. A microbiome gene catalogue from children with caries was constructed for the first time. The results demonstrated that caries is associated with alterations of the oral microbiome, including changes in microbial composition and metabolic functional profile.

19.
ACS Appl Mater Interfaces ; 10(30): 25228-25240, 2018 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-29979563

RESUMEN

Tumor growth inhibition and adverse effect reduction together with metastasis alleviation are still the challenges that need to be overcome in cancer chemotherapy. Combinational therapy provides an alternative solution for these challenges. Nanoparticles are the ideal carriers for combinational therapy due to their versatile drug loading capacities and versatile tumor-targeting strategies. In this study, a cRGDfk modified nanogel system has been utilized to coload lidocaine, a voltage-gated Na+ channels inhibitor, and cisplatin, a common anticancer drug to obtain a tumor-targeted dual drugs-loaded nanogel system. The introduction of lidocaine not only promotes the cisplatin-induced apoptosis in vitro and in vivo but also alleviates the metastasis of MDA-MB-231 breast cancer cells in the mouse model. Besides, the body weight loss caused by cisplatin has also been relieved, and higher dose with less body weight loss can be achieved, which indicated the adverse effect caused by cisplatin-mediated chemotherapy has been alleviated. Furthermore, the introduction of peptide segment-cRGDfk, which presents high affinity to αvß3 integrin, further increases the enrichment of drug-loaded nanogel in the tumor site. It favors the primary tumor growth inhibition. The results demonstrate the coloading of lidocaine and cisplatin by ligand-modified nanogels is a promising strategy for αvß3 integrin-overexpressing breast cancer combinational therapy.


Asunto(s)
Nanopartículas , Animales , Antineoplásicos , Línea Celular Tumoral , Cisplatino , Humanos , Lidocaína , Ratones , Polietileneimina
20.
Carbohydr Polym ; 168: 103-111, 2017 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-28457429

RESUMEN

Cyclodextrin-based supermolecular systems have become one of significant nonviral gene delivery carriers. In this study, epsilon-polylysine-grafted-succinic acid-grafted-ß-cyclodextrin-LMW PEI (PPC) and adamantane-functionalized poly-(ethylene glycol) derivative (PEG-AD) were synthesized, and PEG-AD was encapsulated into PPC to form the complexes. These complexes were used to condense pDNA to make polyplexes, which biophysical properties, cytotoxicity and transfection efficiencies were studied. The results showed that the polyplexes were less cytotoxic than branched PEI without degrading the transfection efficiency. These findings suggest that the complexes with high stability could be an effective and low-toxicity carrier for delivering nucleic acid to target cells.


Asunto(s)
Vectores Genéticos , Polietileneimina , Polilisina , beta-Ciclodextrinas , ADN , Técnicas de Transferencia de Gen , Tamaño de la Partícula , Polietilenglicoles , Transfección
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