RESUMO
Although genetic factors contribute to almost half of all cases of deafness, treatment options for genetic deafness are limited. We developed a genome-editing approach to target a dominantly inherited form of genetic deafness. Here we show that cationic lipid-mediated in vivo delivery of Cas9-guide RNA complexes can ameliorate hearing loss in a mouse model of human genetic deafness. We designed and validated, both in vitro and in primary fibroblasts, genome editing agents that preferentially disrupt the dominant deafness-associated allele in the Tmc1 (transmembrane channel-like gene family 1) Beethoven (Bth) mouse model, even though the mutant Tmc1Bth allele differs from the wild-type allele at only a single base pair. Injection of Cas9-guide RNA-lipid complexes targeting the Tmc1Bth allele into the cochlea of neonatal Tmc1Bth/+ mice substantially reduced progressive hearing loss. We observed higher hair cell survival rates and lower auditory brainstem response thresholds in injected ears than in uninjected ears or ears injected with control complexes that targeted an unrelated gene. Enhanced acoustic startle responses were observed among injected compared to uninjected Tmc1Bth/+ mice. These findings suggest that protein-RNA complex delivery of target gene-disrupting agents in vivo is a potential strategy for the treatment of some types of autosomal-dominant hearing loss.
Assuntos
Proteínas Associadas a CRISPR/administração & dosagem , Edição de Genes/métodos , Genes Dominantes/genética , Terapia Genética/métodos , Perda Auditiva/genética , Estimulação Acústica , Alelos , Animais , Animais Recém-Nascidos , Limiar Auditivo , Sequência de Bases , Proteínas Associadas a CRISPR/metabolismo , Proteínas Associadas a CRISPR/uso terapêutico , Sistemas CRISPR-Cas , Sobrevivência Celular , Cóclea/citologia , Cóclea/metabolismo , Modelos Animais de Doenças , Potenciais Evocados Auditivos do Tronco Encefálico , Feminino , Fibroblastos , Células Ciliadas Auditivas/citologia , Perda Auditiva/fisiopatologia , Perda Auditiva/prevenção & controle , Humanos , Lipossomos , Masculino , Proteínas de Membrana/genética , Camundongos , Reflexo de SobressaltoRESUMO
Regenerated cellulose fiber (RCF) is an environmentally friendly material with outstanding mechanical properties and recyclability, which has been used in a large number of applications. However, during the spinning process using ionic liquids (ILs) as solvents, the dissolved cellulose continues to degrade and even produces degradation products such as glucose, which can enter the recycled solvent and coagulation bath. The presence of glucose can seriously affect the performance of the produced RCFs and hinder their applications, so it has become critical to clarify the regulation and mechanism of this process. In this study, 1-ethyl-3-methylimidazolium diethyl phosphate ([Emim]DEP) with different glucose contents was selected to dissolve wood pulp cellulose (WPC) and obtained RCFs in different coagulation baths. The effect of glucose content in spinning solution on fiber spinnability was investigated by rheological analysis, and the influence of coagulation bath composition and glucose content on the morphological characteristics and mechanical properties of the RCFs was also studied in depth. The results indicated that the morphology, crystallinity, and orientation factor of RCFs were influenced by the presence of glucose in the spinning solution or coagulation bath, resulting in corresponding changes in mechanical properties, which can provide practical reference and guidance for the industrial production of new type fiber.
Assuntos
Glucose , Líquidos Iônicos , Solventes/química , Celulose/química , Líquidos Iônicos/farmacologia , Líquidos Iônicos/químicaRESUMO
Inspired by the action and healing process from living organisms, developing deployable devices using stimuli-responsive materials, or "smart" deployable devices, is desired to realize remote-controlled programmable deformation with additional in situ repair to perform multiple tasks while extending their service life in aerospace. In this work, a photoorganizable triple shape memory polymer (POTSMP) is reported, which is composed of an azobenzene-containing thermoplastic polyurethane. Upon UV and visible illumination, this POTSMP performs arbitrary programming of two temporary shapes and precise and stepwise shape recovery, exhibiting various temporary shapes adapted to different aerospace applications. On the other hand, rapid light-reconfiguration in seconds, including light-reshaping and light-welding, is achieved in response to UV irradiation, allowing in situ localized process and repair of permanent shape. Combining these photoorganizable operations, deformable devices with complex 2D/3D structures are facilely manufactured with no need of special molds. It is envisioned that this POTSMP can expand the potential of photoresponsive TSMPs in smart deployable devices.
Assuntos
Materiais Inteligentes , Polímeros/químicaRESUMO
Combination therapy with pegylated interferon (PEG-IFN) and nucleos(t)ide analogues (NAs) can enhance hepatitis B surface antigen (HBsAg) clearance. However, the specific treatment strategy and the patients who would benefit the most are unclear. Therefore, we assessed the HBsAg loss rate of add-on PEG-IFN and explored the factors associated with HBsAg loss in chronic hepatitis B (CHB) patients. This was a real-world cohort study of adults with CHB. Hepatitis B e antigen (HBeAg)-negative NAs-treated patients with baseline HBsAg ≤1500 IU/ml and HBV DNA < the lower limit of detection, or 100 IU/ml, received 48 weeks of add-on PEG-IFN. The primary outcome of the study was the rate of HBsAg loss at 48 weeks of combination treatment. Using multivariable logistic regression analysis, we determined factors associated with HBsAg loss. HBsAg loss in 2579 patients (mean age: 41.2 years; 80.9% male) was 36.7% (947 patients) at 48 weeks. HBsAg loss was highest in patients from south-central and southwestern China (40.0%). Factors independently associated with HBsAg loss included: increasing age (odds ratio = 0.961); being male (0.543); baseline HBsAg level (0.216); HBsAg decrease at 12 weeks (between 0.5 and 1.0 log10 IU/ml [2.405] and >1.0 log10 IU/ml [7.370]); alanine aminotransferase (ALT) increase at 12 weeks (1.365); haemoglobin (HGB) decrease at 12 weeks (1.558). There was no difference in the primary outcomes associated with the combination regimen. In conclusion, HBsAg loss by combination therapy was higher in patients from southern China than those from the north. An increased chance of HBsAg loss was associated with baseline characteristics and dynamic changes in clinical indicators.
Assuntos
Antígenos de Superfície da Hepatite B , Hepatite B Crônica , Adulto , Antivirais/uso terapêutico , Estudos de Coortes , DNA Viral , Feminino , Antígenos E da Hepatite B , Vírus da Hepatite B/genética , Hepatite B Crônica/tratamento farmacológico , Humanos , Interferon-alfa/uso terapêutico , Masculino , Polietilenoglicóis/uso terapêutico , Resultado do TratamentoRESUMO
Adoptive T cell transfer is one of the most promising ways to combat solid tumors. However, the weak infiltration of T cells into tumor sites has restricted their antitumor efficacy. To overcome this obstacle, we used the lipophilic protein painting strategy to improve tumor targeting and penetrating capacity of lymphocytes for the first time. We synthesized the lipid anchor consisting of a bispecific recombinant protein iRGD-antiEGFR and DSPE-PEG derivates, then successfully inserted it into the membranes of T cells. This surface modification was non-invasive and could efficiently improve the infiltration ability of T cells into multicellular spheroids and tumor masses. The surface modified T cells also displayed superior antitumor activities in EGFR-positive tumor xenografts via systematic infusion. Moreover, the permeability and antitumor efficacy of these surface painted T cells could be remarkably enhanced when used in combination with local low-dose irradiation.
Assuntos
Membrana Celular/metabolismo , Imunoterapia Adotiva/métodos , Linfócitos do Interstício Tumoral/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Anticorpos de Domínio Único/metabolismo , Neoplasias Gástricas/terapia , Linfócitos T/metabolismo , Animais , Linhagem Celular Tumoral , Receptores ErbB/imunologia , Receptores ErbB/metabolismo , Engenharia Genética , Humanos , Lipídeos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Fosfatidiletanolaminas , Polietilenoglicóis , Receptores de Antígenos de Linfócitos T/genética , Anticorpos de Domínio Único/genética , Neoplasias Gástricas/imunologia , Linfócitos T/imunologia , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Flexible microfluidic systems have potential in wearable and implantable medical applications. Directional liquid transportation in these systems typically requires mechanical pumps, gas tanks, and magnetic actuators. Herein, an alternative strategy is presented for light-directed liquid manipulation in flexible bilayer microtubes, which are composed of a commercially available supporting layer and the photodeformable layer of a newly designed azobenzene-containing linear liquid crystal copolymer. Upon moderate visible light irradiation, various liquid slugs confined in the flexible microtubes are driven in the preset direction over a long distance due to photodeformation-induced asymmetric capillary forces. Several light-driven prototypes of parallel array, closed-loop channel, and multiple micropump are established by the flexible bilayer microtubes to achieve liquid manipulation. Furthermore, an example of a wearable device attached to a finger for light-directed liquid motion is demonstrated in different gestures. These unique photocontrollable flexible microtubes offer a novel concept of wearable microfluidics.
Assuntos
Luz , Cristais Líquidos , Microfluídica/instrumentação , Dispositivos Eletrônicos Vestíveis , Compostos Azo/química , Desenho de Equipamento , Humanos , Cristais Líquidos/química , Cristais Líquidos/efeitos da radiação , Microtecnologia , Movimento (Física) , Maleabilidade , Polímeros/química , Polímeros/efeitos da radiaçãoRESUMO
Achieving 'clinical cure' in children with chronic hepatitis B (CHB) with safe and effective antiviral treatment is an unmet medical need. Peginterferon (PegIFN) has higher hepatitis B s antigen (HBsAg) clearance than nucleoside analogs (NUC). Currently, studies on interferon (IFN) in the treatment of Chinese children with CHB are relatively rare. This study aimed to further explore the efficacy of PegIFNα-2a as an antiviral treatment in Chinese children and analyse the long-term follow-up after drug discontinuation. We enrolled 118 patients with CHB (2-16 years old, 79 cases are males) treated with PegIFNα-2a by the author in the Third People's Hospital of Kunming City from February 2009 to February 2015. The course of treatment was 52 weeks, with a follow-up period of 104 weeks. All the patients completed at least 1 dose, of which 104 completed at least 36 weeks of treatment and 104 weeks of follow-up. During treatment and follow-up, indicators such as alanine aminotransferase (ALT), hepatitis B virus (HBV) DNA and HBV serological markers were monitored, and the efficacy and safety of PegIFNα-2a in the treatment of CHB patients were observed. Hepatitis B e antigen (HBeAg) clearance and seroconversion rates were 53.8% and 49%, respectively, when the drug was discontinued; 72.1% and 72.1%, respectively, at the end of the follow-up; and 98.2% and 98%, respectively, for sustained response. HBsAg clearance and seroconversion rates were 48.1% and 47.1%, respectively, when the drug was discontinued; 53.8% and 52.9%, respectively, at the end of the follow-up; and 94% and 95.9%, respectively, for sustained response. The HBV DNA suppression rate was 89.4% when the drug was discontinued, 90.4% at the end of the follow-up and 97.8% for sustained response. Two patients had virological relapse (2.3%) during follow-up; however, no clinical relapse occurred. Multivariate regression analysis showed that genotype B, weight < 25 kg or between 25 and 45 kg, and reduction of HBsAg by more than 1 log following 24 weeks of treatment were independent predictors of HBsAg clearance at the end of follow-up. Adverse events that occurred during treatment were similar to those reported in previous clinical studies on PegIFN. The results of this study showed that PegIFN was safe and effective in the treatment of children with CHB, and sustained response could be achieved after treatment. PegIFN treatment of children with CHB helps more achieve 'clinical cure'.
Assuntos
Antivirais/uso terapêutico , Antígenos E da Hepatite B/sangue , Hepatite B Crônica/sangue , Hepatite B Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico , Adolescente , Fatores Etários , Antivirais/administração & dosagem , Antivirais/efeitos adversos , Biomarcadores , Criança , Pré-Escolar , Progressão da Doença , Feminino , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/virologia , Humanos , Interferon-alfa/administração & dosagem , Interferon-alfa/efeitos adversos , Masculino , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/efeitos adversos , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/uso terapêutico , Fatores de Tempo , Resultado do Tratamento , Carga ViralRESUMO
Photoresponsive blend films with post-crosslinked liquid crystalline polymer (CLCP) as a photosensitive component and flexible polyurethane (PU) as the matrix are successfully fabricated. After being uniaxially stretched, even at low concentration, the azobenzene-containing CLCP effectively transfers its photoresponsiveness to the photoinert PU matrix, resulting in the fast photo-induced bending behavior of whole blend film thanks to the effective dispersion of CLCP. Specifically, the blend film shows photo-induced deformations upon exposure to unpolarized UV light at ambient temperature. The film unbends after thermal treatment, and the randomly orientated mesogens in the film can be realigned by the mechanical stretching, which endows the film with a reversible deformation behavior. The photosensitive blend film possesses favorable mechanical property and good processability at low cost, and it is a promising candidate for a new generation of actuators.
Assuntos
Reagentes de Ligações Cruzadas/química , Cristais Líquidos/química , Polímeros/química , Estrutura Molecular , Processos Fotoquímicos , Temperatura , Raios UltravioletaRESUMO
An extracellular esterase gene estK was identified in Pseudomonas putida mt-2 and overexpressed at high levels in Escherichia coli. The recombinant EstK enzyme was purified and characterized kinetically against p-nitrophenyl ester and other aryl-alkyl ester substrates and found to be selective for hydrolysis of acetyl ester substrates with high activity for p-nitrophenyl acetate (kcat 5.5 Sec-1 , KM 285 µM). Recombinant EstK was found to catalyze deacetylation of acetylated beech xylan, indicating a possible in vivo function for this enzyme, and partial deacetylation of a synthetic polymer (poly(vinylacetate)). EstK was found to catalyze enantioselective hydrolysis of racemic 1-phenylethyl acetate, generating 1R-phenylethanol with an enantiomeric excess of 80.4%.
Assuntos
Esterases/metabolismo , Polivinil/metabolismo , Pseudomonas putida/enzimologia , Xilanos/metabolismo , Acetilação , Biocatálise , Esterases/química , Esterases/isolamento & purificação , Hidrólise , Cinética , Estrutura Molecular , Polivinil/química , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Estereoisomerismo , Xilanos/químicaRESUMO
A magnetic molecularly imprinted fluorescent sensor for the sensitive and convenient determination of ciprofloxacin or norfloxacin in human urine was synthesized and characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, ultraviolet/visible spectroscopy, and fluorescence spectroscopy. Both cadmium telluride quantum dots and ferroferric oxide nanoparticles are introduced into the polymer for the rapid separation and detection of the target molecules. The synthesized molecularly imprinted polymers were applied to detect ciprofloxacin or its structural analog norfloxacin in human urine with the detection limit 130 ng/mL. A computational study was developed to evaluate the template-monomer geometry and interaction energy in the polymerization mixture to determine the reaction molar ratio of the template and monomer molecules.
Assuntos
Ciprofloxacina/urina , Fenômenos Magnéticos , Impressão Molecular , Nanosferas/química , Norfloxacino/urina , Dióxido de Silício/química , Compostos de Cádmio/química , Compostos Férricos/química , Fluorescência , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/química , Humanos , Simulação de Dinâmica Molecular , Estrutura Molecular , Tamanho da Partícula , Polímeros/síntese química , Polímeros/química , Pontos Quânticos , Propriedades de Superfície , Telúrio/químicaRESUMO
Deformable liquid crystal polymers (LCPs), which exhibit both entropic elasticity of polymer networks and anisotropic properties originating from ordered mesogens, have gained more and more interest for use as biomedical soft actuators. Especially, LCP actuators with controllable mesogen alignment, sophisticated geometry and reprogrammability are a rising star on the horizon of soft actuators, since they enable complex and multiple actuations. This review focuses on two topics: (1) the regulation of mesogen alignment and geometry of LCP actuators for complex actuations; (2) newly designed reprogrammable LCP materials for multiple actuations. First, basic actuation mechanisms are briefly introduced. Then, LCP actuators with complex actuations are demonstrated. Special attention is devoted to the improvement of fabrication methods, which profoundly influence the available complexity of the mesogen alignment and geometry. Subsequently, reprogrammable LCP actuators featuring dynamic networks or shape memory effects are discussed, with an emphasis on their multiple actuations. Finally, perspectives on the current challenges and potential development trends toward more intelligent LCP actuators are discussed, which may shed light on future investigations in this field.
Assuntos
Polímeros , Polímeros/química , Cristais Líquidos/químicaRESUMO
In the ionic liquids (ILs) method for processing regenerated cellulose fiber (RCF), which is a high-performance ecologically benign product, metal ion impurities (such as Fe3+ and Cu2+) of cellulose might inevitably remain in the recycled ILs and coagulation bath. The presence of metal ions might negatively impact the properties of the manufactured RCFs and obstruct their applications, which are urgent to be made clear. For this research, the solvent for dissolving wood pulp cellulose (WPC) was 1-ethyl-3-methylimidazolium diethyl phosphate ([Emim]DEP) with various metal ion concentrations. The effect of metal ions in IL on the dissolution of cellulose was investigated by Molecular Dynamics simulations. Rheological analysis and degree of polymerization (DP) analysis were adopted to evaluate the influence on fiber spinnability of different spinning solution metal ion concentrations and various dissolving times. Further, the morphology and mechanical performances of the RCFs variation regulation were also thoroughly researched. The findings showed that the presence of metal ions in the spinning solution affected the DP, crystallinity, and orientation factor of RCFs, which will influence their stress more sensitively than the strain. These findings can serve as a practical guide for the commercial manufacture of emerging fiber.
Assuntos
Celulose , Líquidos Iônicos , Solventes/química , Celulose/química , Líquidos Iônicos/química , ÍonsRESUMO
Cellulose, renowned for its excellent biocompatibility, finds extensive applications in both industrial and laboratory settings. However, few studies have specifically addressed the mechanistic evolution of hydrogen bond networks in cellulose during the dissolution and regeneration processes. In this research, the regeneration mechanism of cellulose in water and ethanol is investigated through molecular dynamics simulations. The results indicate that the ability of water molecules to disrupt hydrogen bonds between cellulose and ionic liquids is stronger than that of ethanol, which is more conducive to promoting the regeneration of cellulose. Besides, the Fourier transform infrared spectroscopy coupled with two-dimensional correlation infrared spectroscopy techniques are employed to unveil the evolution sequence of hydrogen bonds during dissolution and regeneration: ν(OH) (absorbed water) â ν(O3-H3···O5) (intrachain) â ν(O6-H6···O3') (interchain) â ν(O2-H2···O6) (intrachain) â ν(OH) (free). This study not only enhances our understanding of the intricate hydrogen bond dynamics in cellulose dissolution and regeneration but also provides a foundation for the expanded application of cellulose in diverse fields.
Assuntos
Celulose , Ligação de Hidrogênio , Líquidos Iônicos , Simulação de Dinâmica Molecular , Solventes , Água , Celulose/química , Água/química , Solventes/química , Líquidos Iônicos/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Etanol/química , Espectrofotometria InfravermelhoRESUMO
Organic molecules are of great interest for gas sensing applications. However, achieving high-performance gas sensors with high sensitivity, fast response, low consumption, and workability in humid conditions is still challenging. Herein, we report the rational design and synthesis of an ion-in-conjugation polymer, PADC (poly-4,4'-azodianiline-croconamide), obtained by the condensation of croconic acid with 4-4'diaminoazobenzene for gas sensing under humid conditions. The as-fabricated PADC-based gas sensor exhibits ultrahigh sensitivity (802.7 ppm-1 at 1 ppm), subppb detection limit, and high selectivity under humid air with an 80% humidity effect at a temperature down to 350 K. PADC shows good planarity, excellent thermostability, and a narrow band gap of 1.2 eV because of azobenzene fragments spacing previously repulsed biphenyl rings. Compared to previous humidity immunity works, PADC-based sensors realized humidity immunity at a relatively lower temperature, resulting in lower energy consumption.
Assuntos
Dióxido de Nitrogênio , Poli A , Umidade , Polímeros , TemperaturaRESUMO
Metal-organic frameworks (MOF)-polymer hybrid hydrogel solves the processable forming of MOF powder and energy consumption of uranium extraction. However, the hybrid hydrogel by conventional synthesis methods inevitably lead to MOF agglomeration, poor filler-polymer interfacial compatibility and slowly adsorption. Herein, we designed that ZIF-67 was implanted into the carboxymethyl cellulose/polyacrylamide (CMC/PAM) by network-repairing strategy. The carboxyl and amino groups on the surface of CMC/PAM drive the uniform growth of ZIF-67 inside the CMC/PAM, which form an array of oriented and penetrating microchannels through coordination bonds. Our strategy eliminate the ZIF-67 agglomeration, increase the interfacial compatibility between MOF and polymer. The method also improve the free and fast diffusion of uranium in CMC/PAM/ZIF-67 hydrogel. According to the experimental, these enhancements synergistically enabled the CMC/PAM/ZIF-67 have a maximum adsorption capacity of 952â¯mgâ¯g-1. The adsorption process of CMC/PAM/ZIF-67 fits well with pseudo-second-order model and Langmuir isotherm. Meanwhile, the CMC/PAM/ZIF-67 maintain a high removal rate (87.3â¯%) and chemical stability even during ten adsorption-desorption cycles. It is worth noting that the adsorption amount of CMC/PAM/ZIF-67 in real seawater is 9.95â¯mgâ¯g-1 after 20â¯days, which is an ideal candidate adsorbent for uranium extraction from seawater.
Assuntos
Resinas Acrílicas , Carboximetilcelulose Sódica , Estruturas Metalorgânicas , Água do Mar , Urânio , Urânio/química , Urânio/isolamento & purificação , Adsorção , Resinas Acrílicas/química , Carboximetilcelulose Sódica/química , Estruturas Metalorgânicas/química , Água do Mar/química , Hidrogéis/química , Cinética , Purificação da Água/métodos , Poluentes Radioativos da Água/isolamento & purificação , Poluentes Radioativos da Água/químicaRESUMO
In this study, a biodegradable Schiff-base hydrogel urea, possessing substantial water retention and certain slow-release ability was designed and synthesized. Firstly, dialdehyde starch (DAS) and amine-terminated polyethylene glycol (PEG-(NH2)2) were synthesized using potato starch and polyethylene glycol. Then, a novel Schiff-base hydrogel (SH) was prepared through the in-situ reaction between the aldehyde group of DAS and the amino group of PEG-(NH2)2. Three SH based slow-release urea, designated as SHU1, SHU2, and SHU3 and distinguished by varying urea content, were obtained using SH as the substrate. Several characterizations and tests were conducted to determine the structure, thermal properties, morphology, swelling properties, sustainable use, water retention, and biodegradation properties of SH. Additionally, the slow-release behavior of SHU was studied. SEM results revealed that SH possessed a porous three-dimensional network structure, with a maximum water absorption capacity of 4440 % ± 6.23 %. Compared to pure urea, SHU exhibited better slow-release performance after 30 days of release in soil, with SHU1 having a residual nitrogen content of specifically 36.01 ± 0.57 % of the initial nitrogen content. A pot experiment with pakchoi substantiated the water retention and plant growth promotion properties of SHU. This study demonstrated a straightforward method for the preparation of starch-based Schiff-base hydrogels as fertilizer carriers.
Assuntos
Hidrogéis , Ureia , Hidrogéis/química , Ureia/química , Amido/química , Polietilenoglicóis , Bases de Schiff/química , Água/química , NitrogênioRESUMO
Bisphosphonates are potent bone resorption inhibitors, among which alendronate sodium (ALN) is commonly prescribed for most osteoporosis patients, but long-term application of ALN can cause bisphosphonate-related osteonecrosis of jaw (BRONJ), the pathogenesis of which remains unclear. Previous studies have suggested that bisphosphonates cause jaw ischemia by affecting the biological behavior of vascular endothelial cells, leading to BRONJ. However, the impacts of ALN on vascular endothelial cells and its mechanism remain unclear. The purpose of this work is to assess the influence of ALN on human umbilical vein endothelial cells (HUVECs) and clarify the molecular pathways involved. We found that high concentration of ALN induced G1 phase arrest in HUVECs, demonstrated by downregulation of Cyclin D1 and Cyclin D3. Moreover, high concentration of ALN treatment showed pro-apoptotic effect on HUVECs, demonstrated by increased levels of the cleaved caspase-3, the cleaved PARP and Bax, along with decreased levels of anti-apoptotic protein Bcl-2. Further experiments showed that ERK1/2 phosphorylation was decreased. Additionally, ALN provoked the build-up of reactive oxygen species (ROS) in HUVECs, leading to ERK1/2 pathway suppression. N-acetyl-L-cysteine (NAC), a ROS scavenger, efficiently promoted the ERK1/2 phosphorylation and mitigated the G1 phase arrest and apoptosis triggered by ALN in HUVECs. PD0325901, an inhibitor of ERK1/2 that diminishes the ERK1/2 phosphorylation enhanced the ALN-induced G1 phase arrest and apoptosis in HUVECs. These findings show that ALN induces G1 phase arrest and apoptosis through ROS-mediated ERK1/2 pathway inhibition in HUVECs, providing novel insights into the pathogenic process, prevention and treatment of BRONJ in individuals receiving extended use of ALN.
RESUMO
Modulation of steric interactions remote from the active sites within a series of dinuclear bis-propagators derived from racemic 2-4 was used to attenuate the rate of reversible chain transfer between active transition-metal centers and excess equivalents of inactive main-group-metal alkyl species relative to chain growth propagation, as a strategy for achieving the stereoselective living coordinative chain transfer polymerization of propene to provide isotactic stereoblock polypropene. Under identical conditions, the corresponding mononuclear propagator derived from racemic 1 produced only atactic polypropene.
Assuntos
Alcenos/química , Polímeros/síntese química , Estrutura Molecular , Polimerização , Polímeros/química , EstereoisomerismoRESUMO
PURPOSE: Temporomandibular joint osteoarthritis (TMJOA) is a common disease that negatively affects the life quality of human beings. Circadian rhythm acts an important role in life activities. However, whether the clock genes are rhythmic expressed in mandibular condylar chondrocytes, or the clock genes have an effect on the progression of TMJOA remains unknown. In this study, we aim to explore expression of clock genes and regulatory mechanism of TMJOA in rat mandibular condylar chondrocytes. METHODS: After synchronized by dexamethasone, the expression of core clock genes Per1, Per2, Clock, Cry1, Cry2 and Bmal1 and cartilage matrix degrading factor gene Mmp13 were analyzed in mandibular condylar chondrocytes every 4 h with RT-qPCR. The mandibular condylar chondrocytes were stimulated with IL-1ß, and expression of Per1, Mmp13, P65 and p-P65 was assessed by RT-qPCR and Western blot. Sh-Per1 lentivirus was used to assess the effect of clock gene Per1 in IL-1ß-induced chondrocytes, and expression of Mmp13, P65 and p-P65 was measured. After establishing a rat TMJOA model using unilateral anterior crossbite (UAC), micro-CT, H & E, Alcian Blue & Nuclear Fast Red and Safranin O & Fast Green, cartilage thickness was utilized to assess the damage of cartilage and subchondral bone. Immunohistochemistry of PER1, MMP13 and P65 was performed in condylar sections. RESULTS: All core clock genes and Mmp13 were rhythmically expressed. And Mmp13 expression curve was closed in phase and amplitude with Per1. After stimulation with IL-1ß, the expression of MMP13, PER1 and P65 and ratio of p-P65/P65 increased in condylar chondrocytes. After Per1 was down-regulated in condylar chondrocytes, the expression of MMP13 and P65 and ratio of p-P65/P65 decreased. Compared with the condyles of Sham group, the bony parameters of UAC group were significantly worse. The thickness of cartilage in UAC group significantly reduced. The modified Mankin scores and the expression of PER1, MMP13 and P65 in cartilage of UAC group significantly increased compared with Sham group. CONCLUSION: Core clock genes and Mmp13 are rhythmic expressed in rat mandibular condylar chondrocytes. PER1 can regulate the expression of MMP13 through NF-κB pathway in IL-1ß-induced mandibular condylar chondrocytes.
Assuntos
NF-kappa B , Osteoartrite , Animais , Ratos , Condrócitos/metabolismo , Côndilo Mandibular/metabolismo , Metaloproteinase 13 da Matriz/genética , Metaloproteinase 13 da Matriz/metabolismo , NF-kappa B/metabolismo , Osteoartrite/genética , Osteoartrite/metabolismo , Proteínas Circadianas Period/genética , Proteínas Circadianas Period/metabolismo , Articulação Temporomandibular/metabolismoRESUMO
Mutations in Atp2b2, an outer hair cell gene, cause dominant hearing loss in humans. Using a mouse model Atp2b2Obl/+, with a dominant hearing loss mutation (Oblivion), we show that liposome-mediated in vivo delivery of CRISPR-Cas9 ribonucleoprotein complexes leads to specific editing of the Obl allele. Large deletions encompassing the Obl locus and indels were identified as the result of editing. In vivo genome editing promotes outer hair cell survival and restores their function, leading to hearing recovery. We further show that in a double-dominant mutant mouse model, in which the Tmc1 Beethoven mutation and the Atp2b2 Oblivion mutation cause digenic genetic hearing loss, Cas9/sgRNA delivery targeting both mutations leads to partial hearing recovery. These findings suggest that liposome-RNP delivery can be used as a strategy to recover hearing with dominant mutations in OHC genes and with digenic mutations in the auditory hair cells, potentially expanding therapeutics of gene editing to treat hearing loss.