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2.
Phys Chem Chem Phys ; 23(35): 19760-19765, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34524300

RESUMO

Oxo-sulfido molybdenum/tungsten difluorides in the form of Mo(O)(S)F2 and W(O)(S)F2 were prepared in cryogenic matrices via the reactions of laser-ablated metal atoms and SOF2. Both complexes were characterized to possess one oxo, one sulfido and two fluoro ligands terminally bound to the metal center according to the results of infrared spectroscopy combined with isotopic substitution, and non-planar Cs symmetries with closed shell singlet ground states were established on the basis of density functional calculations. The SMoO and SWO bond angles of Mo(O)(S)F2 and W(O)(S)F2 are around 107°, which are close to those of bent MoO22+ and WO22+ (∼101°). Natural bond orbital calculations indicate the presence of a Mo/W-O double bond in Mo(O)(S)F2 and W(O)(S)F2 while the Mo/W-S bond is better described as a triple bond upon F- coordination to SMoO2+ and SWO2+. UV-Vis irradiation is required in order to form the oxo-sulfido molybdenum/tungsten difluorides when metal atoms react with SOF2 in cryogenic matrices.

3.
Invest Ophthalmol Vis Sci ; 62(12): 18, 2021 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-34546326

RESUMO

Purpose: The aim of this study is to evaluate the expression of osteopontin (OPN) and its relationship with relative cytokines in patients with Graves' ophthalmopathy (GO), and to observe the effect of OPN on orbital fibroblasts (OFs) proliferation, migration, and the expression of relative cytokines, as well as the signaling pathways involved in its effect. Methods: The orbital adipose connective tissue was obtained from 24 patients with GO (12 cases of active GO, and 12 cases of inactive GO) and 12 healthy controls. OFs were isolated from orbital tissues obtained from patients with active GO who were undergoing orbital decompression surgery. Quantitative PCR and Western blot were performed to detect RNA and protein expression. The proliferation and cell migration rates of OFs were measured by methylthiazol tetrazolium (MTT) and the cell scratch test. Signaling pathway inhibitors, such as OPN monoclonal antibody 1A12, ERK1/2 inhibitor PD98059, and PI3K inhibitor LY294002, were applied to determine the involved pathways. Results: The mRNA and protein levels of OPN were increased in orbital adipose connective tissue from patients with active GO than those from patients with inactive GO (2.83-fold increase, P < 0.001; 1.91-fold increase, P < 0.05). The OPN mRNA level was positively correlated with CD40 ligand (CD40L) and hyaluronan synthases 2 (HAS2) mRNA in patients with GO. OPN promoted proliferation and migration rate of OFs and induced vascular endothelial growth factor (VEGF) and collagen I mRNA expression, and the effects were inhibited by 1A12 or LY294002. Conclusions: OPN in orbital adipose connective tissues were significantly increase in active GO, and there were significant correlations of OPN with CD40L and HAS2 mRNA levels in patients with GO. OPN promoted proliferation and migration of OFs and induced VEGF and collagen I mRNA expression in OFs through PI3K/Akt signaling pathway. This suggested a role for OPN in the pathogenesis of GO through the activation of OFs.

4.
J Mol Neurosci ; 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34401997

RESUMO

Exosomes harvested from bone marrow-derived mesenchymal stromal cells (BMSCs) have shown treatment potential in many diseases. In vitro, Zeb2/Axin2 stimulated endogenous neurogenesis, which induced functional recovery after stroke. Here, we investigated whether the Zeb2/Axin2-enriched exosomes harvested from BMSCs transfected with a Zeb2/Axin2 overexpression plasmid would enhance neurological recovery. Compared with the control, both exosome treatments significantly improved functional recovery, and Zeb2/Axin2-enriched exosomes had significantly more improved effects on neurological function, neurogenesis, and neurite remodeling/neuronal dendrite plasticity than the control BMSC exosome treatment in a middle cerebral artery occlusion MCAO rat model. After stimulation with Zeb2/Axin2-enriched BMSC exosomes, the spatial memory and nerve function of MCAO rats showed marked recovery. The number of neurons was increased in the subventricular zone (SVZ), hippocampus, and cortex area, while the expression of nerve growth factors (NGF, BDNF, etc.) was upregulated. In the ischemic boundary zone, Zeb2/Axin2-enriched exosomes promoted synaptic remodeling by increasing the number of synapses and reversed the axonal loss of phosphorylated neurofilament (SMI-31) and synaptophysin (SYN) caused by ischemic injury, thus alleviating axonal demise and promoting synaptic proliferation. In vitro, Zeb2/Axin2-enriched exosomes significantly increased neurite branching and elongation of cultured cortical embryonic rat neurons under oxygen- and glucose-deprived (OGD) conditions. Moreover, Ex-Zeb2/Axin2-enriched exosomes downregulated the protein level of SOX10, endothelin-3/EDNRB, and Wnt/ß-catenin expression. In conclusion, exosomes harvested from Ex-Zeb2/Axin2 BMSC could improve post-stroke neuroplasticity and functional recovery in MCAO rats by promoting proliferation and differentiation of neural stem cells. The mechanism may be related to the SOX10, Wnt/ß-catenin, and endothelin-3/EDNRB pathways.

5.
J Am Chem Soc ; 143(34): 13483-13488, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34427439

RESUMO

BN/CC isosterism can give rise to attractive molecules with unique physical or chemical properties. We report here the synthesis, characterization, and reactivities of the boraiminolithium species 2, a room-temperature-stable crystalline solid accessible through a facile dehydrohalogenation/deprotonation reaction. This species, bearing a polarized B≡N triple bond and an anionic N center, is the first example of a BN analogue to the well-known alkynyllithium molecules (lithium acetylides). It has demonstrated a remarkable ability for iminoborane-transfer reactions, which allows for the isolation of a series of unprecedented N-functionalized iminoboranes as well as novel main-group heterocycles. Stable boraiminolithium reagents may become powerful tools in the exploration of new BN-containing building blocks for synthetic chemistry and materials science.

6.
Dalton Trans ; 50(32): 11300-11306, 2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34342320

RESUMO

Sulfur radicals terminally bound to the metal center can be considered as the one-electron reduction products of complexes with terminal sulfido ligands which serve as the reactive sites in enzymes and precursors. However, there is limited information regarding this kind of metal stabilized sulfur radical, which contrasts the more commonly known metal stabilized thiyl radical. In this work, we report the preparation of vanadium, niobium and tantalum radical complexes in the form of M(O)(S)F2 from the reactions of laser-ablated metal atoms and SOF2 in cryogenic matrixes. Combined with the results from infrared spectroscopy and density functional theory calculations, the sulfur ligand in M(O)(S)F2 is characterized to be a terminally bound radical with the unpaired electron located on the sulfur 3p orbital. Besides this radical complex, calculations also predict the existence of MF2(η2-SO) with a side-on SO ligand, but this less stable isomer is not observed as a result of high exothermicity along with its formation from metal atoms and SOF2 that is large enough to overcome the energy barrier towards the occurrence of M(O)(S)F2.

8.
J Hazard Mater ; 419: 126447, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34182419

RESUMO

Hematite (α-Fe2O3) has been commonly used as an eco-friendly catalyst for peroxymonosulfate (PMS) to generate free radicals (SO4•- and/or •OH). However, the activation efficiency of PMS relies heavily on the conversion of Fe(III) to Fe(II) that is slow and rate-limiting. In this study, oxygen vacancies enriched α-Fe2O3 was prepared from thermally treated goethite (α-FeOOH) and employed as a PMS activator. Systematic characterization demonstrated that α-Fe2O3 with most abundant oxygen vacancies could be obtained by heating α-FeOOH at 300 °C. The as-prepared α-Fe2O3 exhibited excellent catalytic activity in activation of PMS for oxidation of sulfamethoxazole (SMX, k = 0.04 min-1). The SMX degradation rate was found to be positively correlated with the concentration of oxygen vacancies. Quenching experiments, EPR, LC/MS and XPS analysis revealed that singlet oxygen (1O2) was the predominant reactive oxygen species. The effects of pH, PMS dosage, catalyst loading, temperature, and anions on SMX degradation were comprehensively investigated. Moreover, the plausible degradation pathways of SMX in the α-Fe2O3/PMS system were proposed. This work not only provides a valuable insight into the mechanism of PMS activation by α-Fe2O3 but also establishes a new strategy for the design of more efficient and practical iron-based catalyst for PMS activation.


Assuntos
Compostos Férricos , Sulfametoxazol , Oxigênio , Peróxidos
9.
Int J Nanomedicine ; 16: 4087-4104, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34163161

RESUMO

Background and Purpose: Cisplatin-paclitaxel (TP) combination chemotherapy as the first-line therapy for numerous cancers is hindered by its inadequate accumulation in tumors and severe side effects resulting from non-specific distribution. The aim of this study is to explore whether TMTP1-modified, cisplatin and paclitaxel prodrugs co-loaded nanodrug could improve cervical cancer chemotherapy and relieve its side effects through active and passive tumor targeting accumulation and controlled drug release. Methods: TDNP, with capacities of active targeting for tumors and controlled drug release, was prepared to co-deliver cisplatin and paclitaxel prodrugs. The characteristics were investigated, including the diameter, surface zeta potential, stability and tumor microenvironment (TME) dependent drug release profiles. Cellular uptake, cytotoxicity, drug accumulation in tumors, antitumor effects and safety analysis were evaluated in vitro and in vivo. Results: The oxidized cisplatin and the paclitaxel linked to the polymer achieved a high loading effciency of over 80% and TME-dependent sustained drug release. Moreover, TMTP1 modification enhanced cellular uptake of TDNP and further improved the cytotoxicity of TDNP in vitro. In vivo, TDNP showed an extended blood circulation and increased accumulation in SiHa xenograft models with the aid of TMTP1. More importantly, TDNP controlled tumor growth without life-threatening side effects. Conclusion: Our study provided a novel TP co-delivery platform for targeted chemotherapy of cervical cancer, which was promising to improve the therapeutic effcacy of TP and may also have application in other tumors.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Portadores de Fármacos/química , Nanopartículas/química , Pró-Fármacos/metabolismo , Microambiente Tumoral/efeitos dos fármacos , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Linhagem Celular Tumoral , Cisplatino/administração & dosagem , Cisplatino/metabolismo , Cisplatino/farmacologia , Feminino , Humanos , Paclitaxel/administração & dosagem , Paclitaxel/metabolismo , Paclitaxel/farmacologia , Polímeros/química , Neoplasias do Colo do Útero/tratamento farmacológico , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Stem Cell Reports ; 16(7): 1662-1673, 2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34115984

RESUMO

Mesenchymal stromal cell (MSC)-derived exosomes play a promising role in regenerative medicine. Their trophic and immunomodulatory potential has made them a promising candidate for cardiac regeneration and repair. Numerous studies have demonstrated that MSC-derived exosomes can replicate the anti-inflammatory, anti-apoptotic, and pro-angiogenic and anti-fibrotic effects of their parent cells and are considered a substitute for cell-based therapies. In addition, their lower tumorigenic risk, superior immune tolerance, and superior stability compared with their parent stem cells make them an attractive option in regenerative medicine. The therapeutic effects of MSC-derived exosomes have consequently been evaluated for application in cardiac regeneration and repair. In this review, we summarize the potential mechanisms and therapeutic effects of MSC-derived exosomes in cardiac regeneration and repair and provide evidence to support their clinical application.

11.
Acta Biochim Biophys Sin (Shanghai) ; 53(7): 893-902, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-33954334

RESUMO

Pre-mRNA processing factor 19 (PRPF19) is a multifaceted protein and participates in DNA damage response and pre-mRNA processing. The role of PRPF19 in cancer is unclear. Here, we report that the expression of PRPF19 in human tongue cancer is associated with unfavorable prognosis. Overexpression of PRPF19 promotes while knockdown of PRPF19 inhibits tongue cancer cell migration, proliferation, and tumor growth. Overexpression of PRPF19 increases the resistance of tongue cancer cells to radiation and cisplatin treatment. Furthermore, PRPF19 regulates the expression of solute carrier family 40 member 1 (SLC40A1) and mono-ADP ribosylhydrolase 2 (MACROD2), knockdown of SLC40A1 or MACROD2 decreases the sensitivity of tongue cancer cells to radiation and cisplatin treatment. Thus, our results establish a key role of PRPF19 in tongue cancer growth and chemoradiotherapy resistance, targeting PRPF19 would be an effective therapeutic strategy for tongue cancer, especially for those resistant to chemoradiotherapy.


Assuntos
Movimento Celular , Proliferação de Células , Quimiorradioterapia , Cisplatino/farmacologia , Enzimas Reparadoras do DNA/metabolismo , Resistencia a Medicamentos Antineoplásicos , Proteínas Nucleares/metabolismo , Fatores de Processamento de RNA/metabolismo , Tolerância a Radiação , Neoplasias da Língua , Animais , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/efeitos da radiação , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Enzimas Reparadoras do DNA/genética , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos da radiação , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteínas Nucleares/genética , Fatores de Processamento de RNA/genética , Tolerância a Radiação/efeitos dos fármacos , Tolerância a Radiação/efeitos da radiação , Radiação Ionizante , Neoplasias da Língua/genética , Neoplasias da Língua/metabolismo , Neoplasias da Língua/patologia , Neoplasias da Língua/terapia , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Insect Sci ; 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33860634

RESUMO

The diamondback moth (DBM) Plutella xylostella (L.) (Lepidoptera: Plutellidae) is an insect pest found around the world that feeds on cruciferous crops. The DBM has become resistant to most insecticides in current use in the field. Broflanilide is a novel meta-diamide insecticide that binds to a new site on the γ-aminobutyric acid receptor and very efficiently protects against most pests in the order Lepidoptera, including DBM. In this study, the resistance of a laboratory-bred susceptible strain of DBM to broflanilide and the fitness costs posed by broflanilide to the DBM were evaluated. The DBM had no obvious resistance to broflanilide after 10 generations of selection. The realized heritability h2 was 0.033, suggesting a low risk of resistance developing in this strain. The F10 generation had no cross-resistance to the insecticides abamectin and endosulfan (which target the γ-aminobutyric acid receptor) and chlorantraniliprole (which targets a non-γ-aminobutyric acid receptor). The specific activities of important detoxification enzymes (cytochrome P450 monooxygenase, esterase, and glutathione S-transferase) were not obviously altered. However, the larval stage was prolonged and the adult stage was shortened significantly in F11 generation than the F0 generation. The total preoviposition period TPOP significantly prolonged 1.90 d in F11 generation. The fitness value Rf (0.93) was lower for the F11 generation than the F0 generation. The results indicated that long-term exposure to broflanilide exerts clear fitness costs in the DBM. This information will be useful in identifying reasonable broflanilide application guidelines for managing broflanilide resistance in the DBM.

13.
Aesthet Surg J ; 2021 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-33647932

RESUMO

BACKGROUND: Temple filler injection is one of the most common minimally invasive cosmetic procedures involving the face; however, vascular complications are not uncommon. OBJECTIVES: This study aimed to investigate the anatomy of the temporal vessels and provide a more accurate protocol for temple filler injection. METHODS: Computed tomography (CT) scans of 56 cadaveric heads injected with lead oxide were obtained. We then used Mimics software to construct 3-dimensional (3D) images of the temporal vessels described by a coordinate system based on the bilateral tragus and right lateral canthus. RESULTS: In the XOY plane, the superficial temporal artery (STA), middle temporal artery (MTA), zygomatico-orbital artery (ZOA), posterior branch of the deep temporal artery (PDTA), and lateral margin of the orbital rim divide the temple into 4 parts (A, B, C, and D). The probabilities of the STA, MTA, ZOA, and PDTA appearing in parts A, B, C, and D were 30.73%, 37.06%, 39.48%, and 77.18%, respectively. In 3D images, these vessels together compose an arterial network that is anastomosed with other vessels, such as the external carotid, facial, and ocular arteries. CONCLUSIONS: 3D CT images can digitally elucidate the exact positions of temporal vessels in a coordinate system, improving the safety of temple filler injections in a clinical setting.

14.
Theranostics ; 11(4): 1641-1654, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33408772

RESUMO

Rationale: Poor survival and engraftment are major hurdles of stem cell therapy in the treatment of myocardial infarction (MI). We sought to determine whether pre-transplantation systemic intravenous administration of human induced pluripotent stem cell (hiPSC)-derived mesenchymal stromal cells (hiPSC-MSCs) could improve the survival of hiPSC-MSCs or hiPSC-derived cardiomyocytes (hiPSC-CMs) following direct intramyocardial transplantation in a mouse model of MI. Methods: Mice were randomized to undergo intravenous administration of saline or 5×105 hiPSC-MSCs one week prior to MI, induced by ligation of the left anterior descending coronary artery. Mice were further assigned to undergo direct intramyocardial transplantation of hiPSC-MSCs (1×106) or hiPSC-CMs (1×106) 10 minutes following MI. Echocardiographic and invasive hemodynamic assessment were performed to determine cardiac function. In-vivo fluorescent imaging analysis, immunofluorescence staining and polymerase chain reaction were performed to detect cell engraftment. Flow cytometry of splenic regulatory T cells (Tregs) and natural killer (NK) cells was performed to assess the immunomodulatory effects. Results: Pre-transplantation systemic administration of hiPSC-MSCs increased systemic Tregs activation, decreased the number of splenic NK cells and inflammation, and enhanced survival of transplanted hiPSC-MSCs and hiPSC-CMs. These improvements were associated with increased neovascularization and decreased myocardial inflammation and apoptosis at the peri-infract zone with consequent improved left ventricular function four weeks later. Co-culture of splenic CD4 cells with hiPSC-MSCs also modulated their cytokine expression profile with a decreased level of interferon-γ, tumor necrosis factor-α, and interleukin (IL)-17A, but not IL-2, IL-6 and IL-10. Conclusion: Pre-transplantation systemic intravenous administration of hiPSC-MSCs induced immunomodulation and facilitated the survival of intramyocardially transplanted cells to improve cardiac function in MI.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos/métodos , Imunomodulação , Células-Tronco Pluripotentes Induzidas/citologia , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/citologia , Infarto do Miocárdio/terapia , Animais , Células Cultivadas , Técnicas de Cocultura , Modelos Animais de Doenças , Humanos , Camundongos , Infarto do Miocárdio/imunologia , Infarto do Miocárdio/patologia
15.
Acta Diabetol ; 58(5): 595-602, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33452595

RESUMO

AIMS: To investigate the association between fibroblast growth factor 21 (FGF21) levels and glycemic response to exenatide in patients with type 2 diabetes. METHODS: The exploratory analysis of a multi-center trial included 190 patients with type 2 diabetes inadequately controlled by monotherapy or combination therapy of metformin and insulin secretagogues. All participants received exenatide twice daily as an add-on therapy for 16 weeks. Serum FGF21 and other information at the baseline and end of follow-ups were obtained. Linear regression analysis was used to determine the correlations between baseline FGF21 levels and HbA1c reduction from baseline after the treatment. RESULTS: After 16 weeks of treatment with exenatide, a decline in the HbA1c levels from baseline was associated with higher baseline FGF21 levels among all participants (r = 0.193, P = 0.008) and in subgroup of the participants receiving background metformin monotherapy (r = 0.231, P = 0.034). Compared with patients in the lowest FGF21 quartile, patients in the highest FGF21 quartile showed a significantly weakened decline in HbA1c levels from baseline among all participants (ß = - 0.16 [95% Cl - 0.31 to - 0.01], P < 0.05) and in subgroup of the participants receiving background metformin monotherapy (ß = - 0.23 [95% Cl - 0.43 to - 0.03], P < 0.05), after adjusting for the confounding factors, including age, sex, and baseline HbA1c levels. CONCLUSIONS: The high baseline FGF21 levels are associated with poor glycemic responses to exenatide in patients with type 2 diabetes. Therefore, FGF21 could be used as a biomarker for predicting the efficacy of exenatide treatment. TRIAL REGISTRATION: ChiCTR-IPR-15006558, date registered May 27, 2015.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Exenatida/uso terapêutico , Fatores de Crescimento de Fibroblastos/sangue , Adulto , Biomarcadores Farmacológicos/análise , Biomarcadores Farmacológicos/sangue , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , China , Diabetes Mellitus Tipo 2/sangue , Quimioterapia Combinada , Exenatida/administração & dosagem , Feminino , Hemoglobina A Glicada/efeitos dos fármacos , Hemoglobina A Glicada/metabolismo , Controle Glicêmico/efeitos adversos , Controle Glicêmico/métodos , Humanos , Hipoglicemiantes/uso terapêutico , Masculino , Metformina/administração & dosagem , Pessoa de Meia-Idade , Resultado do Tratamento
16.
Environ Sci Technol ; 55(3): 1604-1614, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33427447

RESUMO

The occurrence of high-level tigecycline resistance tet(X) variant genes represents a new transferable resistance crisis to food safety and human health. Here, we investigated the abundance of tet(X)-variant genes [tet(X), tet(X1) to tet(X6)] in 33 samples collected from layer manures, manured/un-manured soils, and corresponding lettuce from three provinces in China. The results showed the occurrence of tet(X)/(X2), tet(X3), and tet(X4) in 24 samples. The detection rate of tet(X)/(X2) (23/24) is higher than that of tet(X3) (7/24) and tet(X4) (2/24), and tet(X)/tet(X2) and tet(X3) were found to be enriched and more abundant in most manured soil and several lettuce samples from manured soils than that from manure samples. Twenty six tigecycline-resistant bacteria were isolated, and tet(X)-variant genes were found to be disseminated not only by bacterial clone spreading but also via multidrug resistance plasmids. The total concentrations of tet(X)-variant genes showed significantly positive correlations (R = 0.683, p < 0.001) with ISCR2. Two veterinary tetracyclines (tetracycline and oxytetracycline) and other classes of antimicrobials (enrofloxacin, azithromycin, thiamphenicol, and florfenicol) showed significant correlations with the total concentrations of tet(X)-variant genes (R = 0.35-0.516, p < 0.05). The findings indicate the transmission of tet(X)-variant genes from layer manures to their receiving environmental soils and lettuce and highlight the contribution of veterinary antimicrobials to the spread of tet(X)-variant genes.


Assuntos
Esterco , Solo , Antibacterianos/farmacologia , China , Fazendas , Genes Bacterianos , Alface/genética , Esterco/análise , Microbiologia do Solo , Resistência a Tetraciclina
17.
Stem Cell Res Ther ; 12(1): 13, 2021 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-33413626

RESUMO

BACKGROUND: The creation of a bioengineered cardiac patch (BCP) is a potential novel strategy for myocardial repair. Nevertheless, the ideal scaffold for BCP is unknown. OBJECTIVE: We investigated whether the decellularized placenta (DP) could serve as natural scaffold material to create a BCP for myocardial repair. METHODS AND RESULTS: A BCP was created by seeding human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs; 1 × 106/cm2) onto DP. The functional and electrophysiological properties of the BCP were first characterized by in vitro analysis and optical mapping. Next, in vivo therapeutic efficacy of the BCP was evaluated in a rat model of myocardial infarction (MI), created by left descending coronary artery ligation (MI + BCP group), and compared with MI alone (MI group), transplantation of DP (MI + DP group), and hiPSC-CMs (MI + CM group). Cytokine profiling demonstrated that the BCP contained multiple growth and angiogenic factors, including vascular endothelial growth factor, platelet-derived growth factor, insulin-like growth factor-1, basic fibroblast growth factor, angiogenin, and angiopoietin-2. In vitro optical mapping showed that the BCP exhibited organized mechanical contraction and synchronized electrical propagation. RNA sequencing showed that DP enhanced the maturation of hiPSC-CMs compared with the monolayer of cultured hiPSC-CMs. At 4 weeks follow-up, the BCP significantly improved left ventricular (LV) function, as determined by LV ejection fraction, fractional shortening, + dP/dtmax, and end-systolic pressure-volume relationship, compared with the MI, MI + DP, and MI + CM groups. Moreover, histological examination revealed that engraftment of the BCP at the infarct zone decreased infarct size and increased cell retention and neovascularization compared with the MI, MI + DP, and MI + CM groups. CONCLUSIONS: Our results demonstrate that a DP scaffold contains multiple growth and angiogenic factors that enhance the maturation and survival of seeded hiPSC-CMs. Transplantation of a BCP is superior to DP or hiPSC-CMs alone in reducing infarct size and improving cell retention and neovascularization, thus providing a novel therapy for myocardial repair following MI.


Assuntos
Células-Tronco Pluripotentes Induzidas , Infarto do Miocárdio , Animais , Células Cultivadas , Modelos Animais de Doenças , Feminino , Humanos , Infarto do Miocárdio/terapia , Miocárdio , Miócitos Cardíacos , Placenta , Gravidez , Ratos , Fator A de Crescimento do Endotélio Vascular
18.
Chem Commun (Camb) ; 57(10): 1194-1197, 2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33439178

RESUMO

Examples of chelating ligands that incorporate P-O donors are seldom encountered. Herein, a series of novel bridging diphosphate ligand supported bimetallic Zr(iv), V(iii) and Ni(ii) complexes have been derived from reactions of the oxyphosphorane (C6Cl4O2)P(OEt)3 with the corresponding metal halides. The mechanism is probed and shown to involve elimination of ethyl halide, and ring opening affording the chelating phosphate-catecholate ligands.

19.
Eur Arch Otorhinolaryngol ; 278(2): 323-329, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32462235

RESUMO

OBJECTIVE: White matter lesions (WMLs) are the most common central nervous system changes observed during cochlear implant evaluation. However, its clinical significance in cochlear implantation (CI) remains unclear. The purpose of this study is to explore the effects of WMLs on hearing and speech rehabilitation of prelingually deaf children after CI. METHODS: The data of forty-five children with WMLs who received CI from 2011 to 2014 were retrospectively reviewed. All patients underwent magnetic resonance imaging examination preoperatively. The categories of auditory performance (CAP) and speech intelligibility rating (SIR) scales were used to evaluate changes in the auditory and speech abilities of the patients, and the Fazekas scale was adopted to assess the extent of WMLs. The degree of WMLs was divided into four grades (none, mild, moderate, severe). We assessed hearing and speech abilities at the following time points: 6, 12, 24, 36, 48 and 60-months post-operation. RESULTS: No significant differences in CAP scores were observed between WMLs groups and the control group at 12 months post-CI (p = 0.099), but marked between-group differences were found at 6, 24, 48- and 60-months post-CI. (p < 0.05). Similarly, no significant differences in the SIR scores were observed at 6 months post-CI (p = 0.087), but marked between-group differences were found at 12, 24, 48- and 60- months post-CI. (p < 0.05). Analysis of stratified group results revealed improvements in hearing and speech development for all the subgroups, including the severe WMLs subgroup following CI. However, hearing and speech ability of the severe WMLs subgroup was much slower than that of other groups. CONCLUSIONS: The auditory and speech abilities of prelingually deaf children with WMLs and those without WMLs can improve after CI. Therefore, WMLs should not be considered a contraindication for CI. However, the decision to perform CI in such patients needs a comprehensive evaluation because the post-surgery effects on children with severe WMLs are not ideal.


Assuntos
Implante Coclear , Implantes Cocleares , Surdez , Percepção da Fala , Substância Branca , Criança , Surdez/cirurgia , Humanos , Estudos Retrospectivos , Inteligibilidade da Fala , Resultado do Tratamento , Substância Branca/diagnóstico por imagem
20.
Plast Reconstr Surg ; 147(2): 328-336, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33165294

RESUMO

BACKGROUND: Injection-based techniques for "cheek augmentation" have gained popularity in recent years. The aim of this study was to perform a topographic analysis of the depth and distribution of the vessels in the zygomatic region to facilitate clinical procedures. METHODS: The external carotid arteries of seven cadaveric heads were infused with lead oxide contrast medium. The facial and superficial temporal arteries of another 12 cadaveric heads were injected sequentially with the same medium. Computed tomographic scanning was then performed, and three-dimensional computed tomographic scans were reconstructed using validated algorithms. RESULTS: The vessels on the zygomatic arch received a double blood supply from across the upper and lower borders of the arch, and the number of the vessels varied from one to four. Ninety percent of the vessels on the zygomatic arch were at a depth of 1 to 2.5 mm, and 75 percent were at a depth of 10 to 30 percent of the soft-tissue thickness. The vessels were concentrated on the midline of the zygomatic arch and the lateral margin of the frontal process. All samples showed a vessel travel along the lateral margin of the frontal process that eventually merged into the superior marginal arcades. CONCLUSIONS: This study reported a topographic analysis of the depth and distribution of the vessels in the zygomatic region based on three-dimensional scanning. The results indicated that injection on the zygomatic arch should be performed deep to the bone, and the vascular zones anterior or posterior to the midline of the zygomatic arch were relatively safe injection areas.

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