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Postsurgical peritoneal adhesions are a common and serious postoperative complication after various peritoneal surgeries, such as pelvic and abdominal surgery. Various studies have shown that peritoneal adhesions can be minimized or prevented by physical anti-adhesion barriers, including membranes, knits, and hydrogels. Hydrogels have attracted great attention in preventing peritoneal adhesions because the dimensional architecture of hydrogels is similar to that of the native extracellular matrix. However, chemical cross-linkers had to be used in the preparation of chemical hydrogels, which may have problems in cytotoxicity or unwanted side effects. This fact prompts us to create alternative cross-linking methods for the development of biocompatible hydrogels as physical barriers. Herein, we report a physically cross-linked flexible hyaluronan (HA) cryogel prepared via a freeze-thaw technique as a novel anti-adhesion biomaterial for completely preventing postsurgical peritoneal adhesions. In vitro studies demonstrated that this physically cross-linked HA cryogel exhibited excellent biocompatibility, the inherently desirable biocompatibility and functionality of HA being integrally retained as much as possible. Intriguingly, the rheological properties and appropriate biodegradability of the cryogels were readily tailored and tunable by way of the gelation process. In vivo assessments suggested that the cryogel, as a physical barrier, satisfactorily prevented fibroblast penetration and attachment between the injured tissues and nearby normal organs. Furthermore, the molecular mechanism studies revealed that the HA cryogel could prevent peritoneal adhesion by inhibiting inflammatory response and modulation of the fibrinolytic system. Our results show that HA ultrasoft cryogel is a promising clinical candidate for prolonged adhesion prevention.
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Criogeles , Ácido Hialurónico , Materiales Biocompatibles , Matriz Extracelular , Humanos , Ácido Hialurónico/química , Hidrogeles/química , Adherencias Tisulares/tratamiento farmacológico , Adherencias Tisulares/prevención & controlRESUMEN
This current article explores the differential effects of mindful learning on pro-environmental behavior from the perspective of self-expansion. A total of 253 participants were recruited for four experiments. In Study 1, the mindful-learning group reported greater levels of pro-environmental behavioral intentions compared to a randomized control. In Study 2, we utilized different learning materials focusing on self, humans, or the biosphere in three sub-experiments. Study 2a manipulated mindsets by a self-related focus and revealed participants in a mindfulness condition had lower pro-environmental behavioral intentions than those in the mindlessness group. Study 2b centered on "humans" and results showed that participants in a mindfulness group reported higher levels of pro-environmental behavioral intentions. Finally, Study 2c induced mindsets with a biospheric focus, showing participants in the mindful-learning condition had greater pro-environmental behavioral intentions. Combined, the studies provide empirical evidence that mindful learning could influence self-reported pro-environmental behavioral intentions both positively and negatively.
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Conservación de los Recursos Naturales , Aprendizaje , Atención Plena , Conducta Social , Adolescente , Adulto , Femenino , Humanos , Intención , Masculino , Autoinforme , Adulto JovenRESUMEN
The present study examined how negative feedback influenced implicit self-evaluations and how individuals' level of relational self-construal (RelSC) moderated these relationships. One hundred Chinese university students completed the relational-interdependent self-construal scale and were randomly assigned into one of three conditions (social exclusion, personal failure, or control). After receiving the manipulation, participants completed two Brief Implicit Association Tests (BIATs) that measured their implicit self-liking and self-competence. The results indicated that people with a highly RelSC typically had higher implicit self-liking, but they decreased their implicit self-liking more than those with a low RelSC after experiencing social exclusion. However, RelSC did not influence the effect of personal failure on implicit self-liking. In addition, RelSC was not associated with implicit self-competence in any situation.
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Emociones , Distancia Psicológica , Autoimagen , Adolescente , Autoevaluación Diagnóstica , Femenino , Humanos , Masculino , Distribución Aleatoria , Adulto JovenRESUMEN
OBJECTIVES: To verify the effects of oral appliance (OA) on upper airway morphology under intraluminal pressure, identify specific sites of upper airway collapsibility that can be reversed by OAs, and determine the relationship between OA efficacy and dynamic upper airway changes using computed tomography (CT) with Muller's maneuver. MATERIALS AND METHODS: Nineteen adult Chinese patients with symptomatic mild-to-moderate sleep apnea were recruited from our sleep center. Each patient was fitted with a two-piece OA. Dynamic changes in the retropalatal and retroglossal airway were evaluated using CT at end-expiration and during Muller's maneuver, both with and without an OA. RESULTS: Upper airway changes in the end-expiration phase before OA placement did not significantly differ from those after OA placement. However, under intraluminal pressure induced by Muller's maneuver, OA effectively expanded the upper airway at multiple levels. In addition, OA counteracted negative intraluminal pressure more effectively in the retropalatal region than in the retroglossal region, with 95.65, 68.75, 72.41, and 78.38 % improvements in the collapsibility index of the anteroposterior dimension, transverse dimension, minimum cross-sectional area, and volume of the retropalatal region, respectively. Both nonresponders and responders to OA treatment were sensitive to the intraluminal pressure induced by Muller's maneuver. However, the collapsibility of the retropalatal airway improved significantly only in the responders, not in the nonresponders. CONCLUSIONS: OA effectively treats OSAHS by improving upper airway collapsibility.
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Obstrucción de las Vías Aéreas/diagnóstico , Obstrucción de las Vías Aéreas/terapia , Presión Atmosférica , Avance Mandibular/instrumentación , Ferulas Oclusales , Apnea Obstructiva del Sueño/diagnóstico , Apnea Obstructiva del Sueño/terapia , Adulto , Espiración , Femenino , Humanos , Masculino , Persona de Mediana Edad , Polisomnografía , Tomografía Computarizada de Haz Cónico Espiral , Resultado del TratamientoRESUMEN
AIM: To perform a systematic review to evaluate the erbium-doped: yttrium, aluminium and garnet (Er:YAG) laser versus scaling and root planing (SRP) as alternative or adjuvant for chronic periodontitis treatment. MATERIAL AND METHODS: We performed a literature search using six electronic databases and completed by manual searches up to July 2013. We conducted a meta-analysis as well as heterogeneity, sensitivity, subgroup and power analyses to clarify and validate the pooled results. The 3-, 6- and 12-month clinical outcomes were evaluated. RESULTS: Twelve eligible randomized clinical trials were finally included. Our meta-analysis showed that Er:YAG laser resulted in similar clinical improvements as SRP 3 months postoperatively. For subgroups by laser level, quality of trials and fluorescence feedback device, the results remained consistent. The 6- and 12-month observations between Er:YaG laser and SRP demonstrated no difference but inconclusive, due to large heterogeneity. The advantage of Er:YAG laser adjuvant to SRP for periodontitis treatment was not significant. CONCLUSIONS: This systematic review indicated that the clinical efficacy of Er:YAG laser was similar to SRP 3 months postoperatively. The clinical benefits of Er:YAG laser as adjuvant to SRP was still lacking. Since Er:YAG laser has certain advantages, it could be expected to be a novel short-term alternative choice for chronic periodontitis.
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Periodontitis Crónica/terapia , Raspado Dental/métodos , Terapia por Láser/métodos , Láseres de Estado Sólido/uso terapéutico , Aplanamiento de la Raíz/métodos , Terapia Combinada , Estudios de Seguimiento , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del TratamientoRESUMEN
BACKGROUND: Pediatric condylar fractures combined with symphyseal or parasymphyseal fractures are common but challenging to manage. The authors present fracture characteristics, propose a treatment algorithm, and evaluate the treatment prognosis of pediatric symphyseal/parasymphyseal-condylar fractures. METHODS: A retrospective review was conducted on pediatric patients who underwent treatment for symphyseal/parasymphyseal-condylar fractures in a trauma center between January of 2006 and January of 2021. Demographic and fracture characteristics were recorded. Complications and functional evaluations, including maximum interincisal opening, Helkimo anamnestic index, and clinical dysfunction index, were assessed after at least 1 year of follow-up. RESULTS: After screening, 104 participants met the inclusion criteria. Among them, 50.96% received open reduction and internal fixation for symphyseal/parasymphyseal fractures and closed treatment for condylar fractures, 45.19% were treated by liquid diet and functional exercise, and the remaining 3.85% with severe malocclusion were treated with the assistance of orthodontic appliances. During follow-up, the average maximum interincisal opening of the patients increased from 17 ± 6.29 mm to 41.64 ± 6.33 mm. No subjective symptoms were observed in 86.54% of the patients and 79.81% showed no or mild clinical symptoms. Except for 1 patient who developed temporomandibular joint ankylosis, no other severe complication was reported. Postfracture remodeling of the nonfractured condyle was noted in 3 cases. CONCLUSIONS: Pediatric symphyseal/parasymphyseal-condylar fractures present unique biomechanical and anatomic challenges that require special consideration during management. In this study, satisfactory functional prognosis was achieved following implementation of the treatment algorithm. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.
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Fijación Interna de Fracturas , Cóndilo Mandibular , Fracturas Mandibulares , Humanos , Estudios Retrospectivos , Masculino , Niño , Femenino , Fracturas Mandibulares/cirugía , Fracturas Mandibulares/diagnóstico por imagen , Cóndilo Mandibular/lesiones , Cóndilo Mandibular/cirugía , Cóndilo Mandibular/diagnóstico por imagen , Pronóstico , Fijación Interna de Fracturas/métodos , Adolescente , Preescolar , Resultado del Tratamiento , Algoritmos , Reducción Abierta/métodosRESUMEN
Maxillofacial bone defects exhibit intricate anatomy and irregular morphology, presenting challenges for effective treatment. This study aimed to address these challenges by developing an injectable bioactive composite microsphere, termed D-P-Ak (polydopamine-PLGA-akermanite), designed to fit within the defect site while minimizing injury. The D-P-Ak microspheres biodegraded gradually, releasing calcium, magnesium, and silicon ions, which, notably, not only directly stimulated the osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) but also activated sensory nerve cells to secrete calcitonin gene-related peptide (CGRP), a key factor in bone repair. Moreover, the released CGRP enhanced the osteogenic differentiation of BMSCs through epigenetic methylation modification. Specifically, inhibition of EZH2 and enhancement of KDM6A reduced the trimethylation level of histone 3 at lysine 27 (H3K27), thereby activating the transcription of osteogenic genes such as Runx2 and Osx. The efficacy of the bioactive microspheres in bone repair is validated in a rat mandibular defect model, demonstrating that peripheral nerve response facilitates bone regeneration through epigenetic modification. These findings illuminated a novel strategy for constructing neuroactive osteo-inductive biomaterials with potential for further clinical applications.
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Regeneración Ósea , Células Madre Mesenquimatosas , Microesferas , Osteogénesis , Animales , Ratas , Células Madre Mesenquimatosas/metabolismo , Regeneración Ósea/genética , Regeneración Ósea/efectos de los fármacos , Regeneración Ósea/fisiología , Osteogénesis/fisiología , Osteogénesis/genética , Diferenciación Celular , Desmetilación , Ratas Sprague-Dawley , Modelos Animales de Enfermedad , Cerámica , Histonas/metabolismo , Histonas/genética , Péptido Relacionado con Gen de Calcitonina/metabolismo , Péptido Relacionado con Gen de Calcitonina/genética , Masculino , Materiales Biocompatibles/metabolismoRESUMEN
Marginal lands, such as those with saline soils, have potential as alternative resources for cultivating dedicated biomass crops used in the production of renewable energy and chemicals. Optimum utilization of marginal lands can not only alleviate the competition for arable land use with primary food crops, but also contribute to bioenergy products and soil improvement. Miscanthus sacchariflorus and M. lutarioriparius are prominent perennial plants suitable for sustainable bioenergy production in saline soils. However, their responses to salt stress remain largely unexplored. In this study, we utilized 318 genotypes of M. sacchariflorus and M. lutarioriparius to assess their salt tolerance levels under 150 mM NaCl using 14 traits, and subsequently established a mini-core elite collection for salt tolerance. Our results revealed substantial variation in salt tolerance among the evaluated genotypes. Salt-tolerant genotypes exhibited significantly lower Na+ content, and K+ content was positively correlated with Na+ content. Interestingly, a few genotypes with higher Na+ levels in shoots showed improved shoot growth characteristics. This observation suggests that M. sacchariflorus and M. lutarioriparius adapt to salt stress by regulating ion homeostasis, primarily through enhanced K+ uptake, shoot Na+ exclusion, and Na+ sequestration in shoot vacuoles. To evaluate salt tolerance comprehensively, we developed an assessment value (D value) based on the membership function values of the 14 traits. We identified three highly salt-tolerant, 50 salt-tolerant, 127 moderately salt-tolerant, 117 salt-sensitive, and 21 highly salt-sensitive genotypes at the seedling stage by employing the D value. A mathematical evaluation model for salt tolerance was established for M. sacchariflorus and M. lutarioriparius at the seedling stage. Notably, the mini-core collection containing 64 genotypes developed using the Core Hunter algorithm effectively represented the overall variability of the entire collection. This mini-core collection serves as a valuable gene pool for future in-depth investigations of salt tolerance mechanisms in Miscanthus.
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Cartilage regeneration remains a current challenge with no satisfactory strategy in surgery. Hydrogels with structurally and biochemically biomimicking characteristics have been regarded as a promising approach for the success of cartilage regeneration. Naturally sourced hydrogels from exopolysaccharides are ideal candidates for the construction of biomimetic extracellular matrix (ECM) because of their biomimetic networks, high water content, cytocompatibility, and biodegradability. Here, an approach that integrates covalent and ionic bonds in a hydrogel system is shown to form a natural polymeric hydrogel double network (DN) for promoting the adhesion and proliferation of chondrocytes and supporting the formation of matured cartilage tissue. DN hydrogels comprised of chemically crosslinked hyaluronan (HA) and physically crosslinked gellan gum (GG) were developed for potential scaffold fabrication. Compared with HA single network (SN) hydrogel and GG SN hydrogel, the obtained HA/GG DN hydrogel with Young's modulus of 28.6 kPa exhibited adequate compressive strength (208.9 kPa) and high toughness (dissipated energy 2837 J/m3) and thus can be used as a biomimetic extracellular matrix for minimal invasively repairing cartilage. In vitro studies showed that HA/GG DN hydrogel-based ECM promoted the proliferation of chondrocytes. The HA/GG DN hydrogel significantly supported the deposition of cartilage ECM-specific sulfated glycosaminoglycan and type II collagen and facilitated the formation of cartilage tissues. In a rabbit osteochondral defect model, HA/GG DN hydrogel significantly improved cartilage regeneration. The HA/GG DN hydrogel as a biomimetic ECM is a promising candidate as a biomaterial scaffold for cartilage regeneration and repair. STATEMENT OF SIGNIFICANCE: The fabrication of a biomaterial scaffold as an artificial extracellular matrix (ECM) for cartilage regeneration remains a big challenge. In this work, we fabricated a double-network (DN) hydrogel based on hyaluronan and gellan gum (HA/GG) through a sequential chemical and physical cross-linking process. The HA/GG DN hydrogel exhibited high compressive strength, high toughness, stiffness, and good self-recovery property. The HA/GG DN hydrogel can support chondrocyte proliferation and new ECM deposition correlated with the enhanced mechanical properties, good cytocompatibility, and biodegradability. In vivo animal experiments demonstrated that this HA/GG DN hydrogel facilitates hyaline-like cartilage regeneration. These findings imply that the developed HA/GG DN hydrogel as a biomimetic ECM offers a hopeful new platform for cartilage tissue engineering.
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Cartílago Articular , Hidrogeles , Animales , Materiales Biocompatibles , Biomimética , Colágeno Tipo II , Matriz Extracelular , Ácido Hialurónico/química , Ácido Hialurónico/farmacología , Hidrogeles/química , Hidrogeles/farmacología , Conejos , Regeneración , AguaRESUMEN
Background: The dysfunction of Essential meiotic endonuclease 1 homolog 1 (EME1) can lead to genomic instability and tumorigenesis. Single nucleotide polymorphisms (SNPs) in the EME1 gene have been reported to be associated with the risk of several cancers, but its association with hepatocellular carcinoma (HCC) has not been investigated. This study aimed to determine the association between EME1 SNPs and the risk of HCC. Methods: This study included 645 HCC patients and 649 healthy controls from a Guangxi population of Southern China, and genotyped three functional SNPs (Glu69Asp: rs3760413A>C, Ile350Thr: rs12450550T>C, and rs11868055A>G) of the EME1 gene utilizing the Agena MassARRAY platform. Results: The rs3760413C variant genotypes (AC+CC: Glu/Asp+Asp/Asp) conferred a 1.419-fold risk of HCC compared to the AA (Glu/Glu) genotype (adjusted OR = 1.419, 95% CI = 1.017-1.980), and the allele C increased the risk of HCC in a dose-dependent manner (P trend = 0.017). Moreover, the effects of the rs3760413C variant genotypes were more pronounced in individuals who drank pond/ditch water (adjusted OR = 3.956, 95% CI = 1.413-11.076) than in those who never drank (P = 0.033). We further observed that a potential carcinogen microcystin-LR induced more DNA oxidative damages in peripheral blood mononuclear cells from the carriers of rs3760413C variant genotypes than those from the subjects with AA genotype (P = 0.006). A nomogram was also constructed combining the rs3760413A>C polymorphism and environmental risk factors for predicting HCC risk with a good discriminatory ability (concordance index = 0.892, 95% CI: 0.874-0.911) and good calibration (mean absolute error = 0.005). Conclusion: Our data suggest that the Glu69Asp missense polymorphism (rs3760413) of EME1 gene is associated with the risk of HCC, which may be a susceptible biomarker of HCC in the Guangxi population.
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Due to the worldwide impact of SARS-CoV-2, people have carried out in-depth research on the virus to fight against this highly contagious disease. In this article, many articles published recently are summarized vertically, from the structure and sites of SARS-Cov-2, the mode of transmission, the mathematical model of transmission, the mechanism of the virus itself, the symptoms of patients after infection to medicine used in the early stage period and the prediction as well the analysis of probability in using new medicine.
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Antivirales/uso terapéutico , Tratamiento Farmacológico de COVID-19 , COVID-19/epidemiología , Animales , COVID-19/transmisión , China/epidemiología , Quirópteros/virología , Salud Global , Humanos , SARS-CoV-2/química , SARS-CoV-2/efectos de los fármacos , SARS-CoV-2/genética , SARS-CoV-2/patogenicidadRESUMEN
Tissue engineering is an interdisciplinary field that aims to develop biological substitutes for the replacement, repair, or enhancement of tissue function. The physical and chemical characteristics of biomaterials exert a profound influence on the biological responses and the following biofunction. Nanostructured coatings have been widely applied as an effective surface modification strategy to improve the bioactivity of biomaterials. Especially, polydopamine and polydopamine-derived nanoparticles are found with excessive adhesiveness, redox activity, photothermal conversion capacity, paramagnetism and conductivity other than excellent biocompatibility, and hydrophilicity. In this article, advances about polydopamine nanoparticles in tissue engineering applications are reviewed, including the repair of bone, cartilage, skin, heart, and nerve, to provide strategies for future biomaterial design.
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BACKGROUND: Protein phosphatase 2A (PP2A, a serine/threonine phosphatase) is frequently inactivated in many types of cancer, including primary liver cancer (PLC). Genetic variations in PP2A subunits have been reported to be associated with the risk of many types of cancer but rarely in PLC. This study aims to assess the association between functional polymorphisms of PP2A subunit genes and the risk of PLC in Chinese. METHODS: In a case-control study with a total of 541 PLC patients and 547 controls in Guangxi province of Southern China, we genotyped six putatively functional polymorphisms (rs10421191G>A, rs11453459del>insG, rs1560092T>G, rs7840855C>T, rs1255722G>A and rs10151527A>C) of three PP2A subunit genes (PPP2R1A, PPP2R2A and PPP2R5E) using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry platform. RESULTS: The rs11453459insG variant genotypes (ins/ins+del/ins) of PPP2R1A were found to be significantly associated with an increased risk of PLC compared with the del/del genotype (adjusted OR = 1.290, 95% CI = 1.009-1.650), and the number of insert G allele worked in a dose-dependent manner (P trend= 0.007). The stratified analysis showed that the effects of rs11453459insG variant genotypes were more evident in the subgroup who drink pond-ditch water (adjusted OR = 3.051, 95% CI = 1.264-7.364) than those never drink (P = 0.041). The carriers of rs11453459 del/ins genotype had a significantly lower level of PPP2R1A mRNA expression in liver cancer tissues than those of the del/del genotype (P = 0.021). Furthermore, we used microcystin-LR, a carcinogen presents in the pond-ditch water, to treat human peripheral blood mononuclear cells and found that the cells from carriers of rs11453459insG variant genotypes induced more DNA oxidative damages than those from the del/del genotype carriers (P < 0.001). CONCLUSION: These findings suggest that the PPP2R1A rs11453459del>insG polymorphism is associated with an increased risk of PLC, especially for persons with a history of drinking pond-ditch water. This insertion/deletion polymorphism may be a susceptible biomarker for PLC in Chinese.
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Irreversible marginal bone loss can hinder recovery around dental implants. Insufficient alveolar osteogenesis and stress concentration during chewing contribute to marginal bone resorption and can result in implant failure. A biomaterial with a micropore-channel structure was developed using 3D printing technology. This design facilitated bony ingrowth and provided similar mechanical stimulation at the implant neck during mastication to a natural tooth. The micropore channels provided a guiding structure for bone mesenchymal stem cell proliferation and differentiation without the need for growth factors. Specifically, this was achieved through mechanical transduction by F-actin remodeling and the activation of Yes-associated protein (YAP). The implants were verified in a canine dental implant surgery model, which demonstrated the promising use of biomaterial-based dental implants in future clinical applications.
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Injectable hydrogels are attractive biomaterials for cell delivery in tissue engineering. However, the in vivo viability of transplanted cells remains limited. Typically, macroporous structures constructed in hydrogels are utilized to enhance oxygen and nutrients diffusion for cell survival and to promote integration between the material and host tissue. A new gas-foaming method to generate pores was proposed by directly adding Mg particles into cell-laden hydrogel solutions, taking advantage of the H2 gas formed during the degradation of Mg. The optimization design of the size and amount of Mg particles added into the hydrogels was investigated. Improved cell viability and proliferation were demonstrated in the group with Mg particles. Additionally, Mg2+ ions generated during Mg degradation facilitated the osteogenic differentiation of stem cells encapsulated in hydrogels. Extensive vascularized bone regeneration in the femoral defects of rats revealed that the use of Mg particles as the foaming agent is feasible, endowing injectable hydrogels with optimized porosity and enhanced bioactivity, and providing a new strategy for future designs of porous hydrogels in tissue engineering.
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Hidrogeles , Magnesio , Animales , Regeneración Ósea , Osteogénesis , Ratas , Ingeniería de TejidosRESUMEN
OBJECTIVE: This study aimed to evaluate the effects of nasal obstruction on mandibular growth, especially condyle, in adolescent rats and explore the possible mechanism with a focus on mesenchymal stem cells (MSCs) from condylar tissues. DESIGN: 4-week-old male Sprague-Dawley rats were randomly divided into bilateral intermittent nasal obstruction (i.e. mouth-breathing, MB) and nasal-breathing (NB) groups. Self-made plugs were used to obstruct the nasal cavity in the MB group for 4 weeks, from 8:00 a.m. to 4:00 p.m. every day. The body weights were recorded. Three-dimensional computed tomography (3D-CT) scanning of the craniomaxillary region was performed after 2 and 4 weeks of nasal obstruction. Other rats were sacrificed, and MSCs were isolated from condylar tissues and cultured in vitro for examining the cell proliferation and expression of chondrogenic marker genes. RESULTS: Significant decreases in body weight were observed in the MB group compared with the NB group during 4 weeks of nasal obstruction. All mandibular parameters in the sagittal, vertical, and transverse dimensions (except bi-condylar width) measured via 3D-CT were significantly smaller in the MB group. No significant difference was found in the proliferative ability of cultured MSCs derived from condylar tissues between the two groups. However, the expression of chondrogenic marker genes Acan, Col2a1 and Sox9 was significantly lower in the MB group-derived MSCs, using Cell Counting Kit-8 and quantitative polymerase chain reaction. CONCLUSION: The findings suggested that mouth breathing forced by nasal obstruction lead to developmental defects in the mandibular condyle, which might be related to the reduced cartilage differentiation of condylar MSCs.
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Cóndilo Mandibular/patología , Células Madre Mesenquimatosas/citología , Obstrucción Nasal/complicaciones , Animales , Células Cultivadas , Condrogénesis , Masculino , Cóndilo Mandibular/citología , Distribución Aleatoria , Ratas , Ratas Sprague-DawleyRESUMEN
The redevelopment/regeneration pattern of amputated limbs from a blastema in salamander suggests that enhanced regeneration might be achieved by mimicking the developmental microenvironment. Inspired by the discovery that the expression of magnesium transporter-1 (MagT1), a selective magnesium (Mg) transporter, is significantly upregulated in the endochondral ossification region of mouse embryos, a Mg-enriched 3D culture system is proposed to provide an embryonic-like environment for stem cells. First, the optimum concentration of Mg ions (Mg2+) for creating the osteogenic microenvironment is screened by evaluating MagT1 expression levels, which correspond to the osteogenic differentiation capacity of stem cells. The results reveal that Mg2+ selectively activates the mitogen-activated protein kinase/extracellular regulated kinase (MAPK/ERK) pathway to stimulate osteogenic differentiation, and Mg2+ influx via MagT1 is profoundly involved in this process. Then, Mg-enriched microspheres are fabricated at the appropriate size to ensure the viability of the encapsulated cells. A series of experiments show that the Mg-enriched microenvironment not only stimulates the osteogenic differentiation of stem cells but also promotes neovascularization. Obvious vascularized bone regeneration is achieved in vivo using these Mg-enriched cell delivery vehicles. The findings suggest that biomaterials mimicking the developmental microenvironment might be promising tools to enhance tissue regeneration.
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Chromosomes of four Miscanthus (Andersson, 1855) species including M. sinensis (Andersson, 1855), M. floridulus (Schumann & Lauterb, 1901), M. sacchariflorus (Hackel, 1882) and M. lutarioriparius (Chen & Renvoize, 2005) were analyzed using sequentially combined PI and DAPI (CPD) staining and fluorescence in situ hybridization (FISH) with 45S rDNA probe. To elucidate the phylogenetic relationship among the four Miscanthus species, the homology of repetitive sequences among the four species was analyzed by comparative genomic in situ hybridization (cGISH). Subsequently four Miscanthus species were clustered based on the internal transcribed spacer (ITS) of 45S rDNA. Molecular cytogenetic karyotypes of the four Miscanthus species were established for the first time using chromosome measurements, fluorochrome bands and 45S rDNA FISH signals, which will provide a cytogenetic tool for the identification of these four species. All the four have the karyotype formula of Miscanthus species, which is 2n = 2x = 38 = 34m(2SAT) + 4sm, and one pair of 45S rDNA sites. The latter were shown as strong red bands by CPD staining. A non-rDNA CPD band emerged in M. floridulus and some blue DAPI bands appeared in M. sinensis and M. floridulus. The hybridization signals of M. floridulus genomic DNA to the chromosomes of M. sinensis and M. lutarioriparius genomic DNA to the chromosomes of M. sacchariflorus were stronger and more evenly distributed than other combinations. Molecular phylogenetic trees showed that M. sinensis and M. floridulus were closest relatives, and M. sacchariflorus and M. lutarioriparius were also closely related. These findings were consistent with the phylogenetic relationships inferred from the cGISH patterns.
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PURPOSE: The cone beam computed tomography (CBCT) images of 2 closed treatments are compared for intracapsular condylar fractures (ICFs) to learn whether splint treatment could promote better radiologic outcomes. PATIENTS AND METHODS: Fifty-four patients with 60 sides of ICF were divided into 2 groups. In the control group (C-group), patients had a liquid diet for 1 month. In the trial group (T-group), patients wore splints with anterior elastic traction. Local CBCT images of the temporomandibular joint were obtained at T0 (mean 8.8 days), T1 (mean 37.4 days), and T3 (mean 3.3 months) after trauma. Six parameters, including 2 horizontal, 1 sagittal, and 3 vertical distances, were calculated using the coordinates of 10 points marked on CBCT sections. Statistical analysis included intragroup comparison at T0, T1, and T3, and intergroup comparison among subgroups classified by age and ICF types. RESULTS: Compared to C-group, vertical distances were significantly changed in T-group, specifically in adults and patients with ICF type B. Significant changes at stage T1 were also observed in T-group. CONCLUSION: During the natural healing process, ICF healed in the displaced position and the stump tended to move closer to the joint fossa in the vertical dimension. Splint treatment with elastic traction was helpful to increase joint space and promote better radiologic healing shape.
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Tomografía Computarizada de Haz Cónico , Fijación de Fractura/métodos , Fracturas Cerradas/diagnóstico por imagen , Fracturas Cerradas/terapia , Cóndilo Mandibular , Fracturas Mandibulares/diagnóstico por imagen , Fracturas Mandibulares/terapia , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Curación de Fractura , Humanos , Masculino , Cóndilo Mandibular/diagnóstico por imagen , Cóndilo Mandibular/lesiones , Persona de Mediana Edad , Resultado del TratamientoRESUMEN
BACKGROUND: Children with severe airway obstruction tend to have a vertical direction of growth, class II malocclusion, and narrow arches. Adenoidectomy and tonsillectomy were recommended for the promotion of balanced dentition growth in these children.The aim of this study was to determine the effect of adenoidectomy and tonsillectomy on the growth of dental morphology in children with airway obstruction. METHODS: A comprehensive search of the Medline, Embase, Web of science, and OVID databases for studies published through to January 17, 2016 was conducted. Prospective, comparative, clinical studies assessing the efficacy of adenoidectomy, or tonsillectomy in children with airway obstruction were included. The weighted mean difference (WMD) and 95% confidence interval (CI) were used for continuous variables. Forest plots were drawn to demonstrate effects in the meta-analyses. RESULTS: Eight papers were included in our study. We found that adenoidectomy and tonsillectomy led to a significant change in nasal-breathing in children with airway obstruction. Children with airway obstruction had a significantly narrower posterior maxillary dental arch than children without airway obstruction (WMD = -0.94, 95% CI [-1.13, -0.76]; Pâ<â0.001). After surgery, these children still had a significantly narrower dental arch than the nasal-breathing children (WMD = -0.60, 95% CI [-0.79, -0.42]; Pâ<â0.001). In terms of dental arch width, malocclusion, palatal height, overjet, overbite, dental arch perimeter, and arch length, a tendency toward normalization was evident following adenoidectomy or tonsillectomy, with no significant differences evident between the surgical group and the normal group. The small number of studies and lack of randomized controlled trials were the main limitations of this meta-analysis. CONCLUSIONS: Following adenoidectomy and tonsillectomy, the malocclusion and narrow arch width of children with airway obstruction could not be completely reversed. Therefore, other treatments such as functional training or orthodontic maxillary widening should be considered after removing the obstruction in the airway.