Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 40
Filtrar
1.
Inorg Chem ; 63(18): 8336-8341, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38651971

RESUMO

A cube-like Zn(II)-Eu(III) nanocluster 1 (molecular sizes: 1.8 × 2.0 × 2.0 nm) was constructed by the use of a new long-chain Schiff base ligand. It shows a ratiometric fluorescence response to levofloxacin (LFX) with high sensitivity and selectivity, which can be expressed as I615 nm/I550 nm = A*[LFX]2 + B*[LFX] + C. It is used to quantitatively detect the LFX concentrations in fetal calf serum (FCS) and tablets sold in pharmacy. Filter paper strips bearing 1 can be used to qualitatively detect LFX by a color change to red under a UV lamp. 1 and its hybrid with sodium alginate (SA), 1@SA, display potential applications in the qualitative detection of LFX in FCS and the medicine. The limit of detection of 1 to LFX is as low as 2.1 × 10-2 nM.


Assuntos
Alginatos , Európio , Levofloxacino , Zinco , Alginatos/química , Zinco/química , Zinco/sangue , Levofloxacino/sangue , Levofloxacino/análise , Európio/química , Espectrometria de Fluorescência , Animais , Humanos , Bovinos , Comprimidos , Corantes Fluorescentes/química
2.
Inorg Chem ; 63(16): 7199-7205, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38602179

RESUMO

A nine-metal Zn(II)-Eu(III) nanoring 1 with a diameter of about 2.3 nm was constructed by the use of a long-chain Schiff base ligand. It shows a luminescence response to neopterin (Neo) through the enhancement of lanthanide emission with high selectivity and sensitivity, which can be used to quantitatively analyze the concentrations of Neo in fetal calf serum and urine. The luminescence sensing of 1 to Neo is temperature-dependent, and it displays more obvious response behavior at lower temperatures. Filter paper strips bearing 1 can be used to qualitatively detect Neo by the color change from chartreuse to red under a UV lamp. The limit of detection is as low as 3.77 × 10-2 nM.


Assuntos
Európio , Nanoestruturas , Neopterina , Temperatura , Zinco , Zinco/química , Zinco/análise , Neopterina/análise , Neopterina/urina , Neopterina/sangue , Európio/química , Nanoestruturas/química , Humanos , Luminescência , Medições Luminescentes , Biomarcadores/análise , Biomarcadores/sangue , Limite de Detecção , Animais
3.
Inorg Chem ; 63(17): 7613-7618, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38632683

RESUMO

Meloxicam (MLX) is a novel nonsteroidal anti-inflammatory drug, but on the other hand, it has become one of the common microcontaminants in surface waters and sewage. Herein, we report the preparation of a ternary-metal Zn(II)-Cd(II)-Eu(III) nanocluster 1 for the response of MLX through the enhancement of lanthanide luminescence. The luminescence sensing behavior of 1 is expressed by the equation I615nm = 3060 × [MLX] + 46,604, which can be used in the quantitative analysis of MLX concentrations in meloxicam dispersible tablets. Filter paper strips bearing 1 can be used to qualitatively detect MLX by a color change to red under a UV lamp. The luminescence response time is no more than five s, and the detection limit is as low as 2.31 × 10-2 nM.


Assuntos
Anti-Inflamatórios não Esteroides , Európio , Meloxicam , Zinco , Meloxicam/análise , Zinco/química , Zinco/análise , Európio/química , Anti-Inflamatórios não Esteroides/análise , Anti-Inflamatórios não Esteroides/química , Medições Luminescentes , Luminescência , Nanoestruturas/química , Limite de Detecção
4.
Inorg Chem ; 62(6): 2508-2512, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36722726

RESUMO

A near-IR-luminescent octanuclear Yb(III) complex 1 was constructed from a new dodecadentate Schiff base ligand, which is used in the rapid and reliable wavelength-dependent detection of aloe emodin (AE) with high sensitivity even in the presence of other interferences.


Assuntos
Emodina , Ligantes , Bases de Schiff , Antraquinonas
5.
Int Orthop ; 45(7): 1803-1810, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33594466

RESUMO

PURPOSE: This study aims to investigate the application value of O-arm navigation system in sacroiliac screw placement for the treatment of unstable pelvic ring injury. METHODS: A total of 40 patients (mean age = 30.75 ± 14.99 years, 25 males, 15 females) were included. From January 2016 to July 2018, 40 patients with posterior pelvic ring injury treated in our hospital were included. Of them, 19 patients underwent O-arm navigation for screw placement (O-arm group) while the other 21 received C-arm fluoroscopy guidance (C-arm group) for sacroiliac screw placement. Intraoperative outcomes and the outcome of screw placement were compared between groups. The quality of radiological images was assessed by Matta's radiological outcome grade. The outcome of complex pelvic fracture treatment was evaluated by Majeed Functional score. RESULTS: All demographic and clinical characteristics were comparable between the two groups. Compared with the C-arm groups, the O-arm group had a shorter surgery time (33.19 ± 3.14 vs. 48.35 ± 4.38 min, P < 0.001), a higher overall good outcome "excellent + good" rate of screw placement (95.45% vs. 73.91%, P < 0.05), and a significantly higher Majeed Functional score better outcome of complex pelvic fracture treatment at 1 and 3 months postoperation (both P < 0.05). CONCLUSION: Our results demonstrated that O-arm navigation system is feasible and safe for the treatment of posterior pelvic ring injury and can effectively improve the accuracy and safety of sacroiliac screw placement, shorten the operation time, and help rapid postoperative functional recovery.


Assuntos
Fraturas Ósseas , Ossos Pélvicos , Cirurgia Assistida por Computador , Adolescente , Adulto , Parafusos Ósseos , Feminino , Fixação Interna de Fraturas , Fraturas Ósseas/diagnóstico por imagem , Fraturas Ósseas/cirurgia , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Ossos Pélvicos/diagnóstico por imagem , Ossos Pélvicos/cirurgia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Adulto Jovem
6.
J Obstet Gynaecol Res ; 46(11): 2347-2355, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32856391

RESUMO

AIM: This study was designed to evaluate the effects of intrauterine transplantation of menstrual blood stem cells (MenSCs) on endometrial thickness and pregnancy outcomes in patients with refractory intrauterine adhesion (IUA). METHODS: This study included a group of infertile women (n = 12, age 22-40 years), with refractory IUA. Autologous MenSCs isolated from the women's menstrual blood were expanded in vitro and transplanted into their uteruses, followed by hormone replacement therapy. Transvaginal ultrasound examination was performed to assess the endometrial thickness. Transabdominal ultrasound was conducted to detect pregnancy outcome. RESULTS: Autologous MenSCs were successfully isolated and expanded from menstrual blood and transplanted into the uterus of each patient. A significant improvement of the endometrial thickness was observed from 3.9 ± 0.9 to 7.5 ± 0.6 mm (P < 0.001). No adverse reaction was observed. The duration of menstruation was increased from 2.4 ± 0.7 to 5.3 ± 0.6 days (P < 0.001). Five out of 12 patients achieved clinical pregnancy and the pregnancy rate was 41.7%. CONCLUSIONS: Intrauterine transplantation of autologous MenSCs results in regeneration of endometrium, a prolongation of menstrual duration and an increase rate of pregnancy in patients with refractory IUA.


Assuntos
Infertilidade Feminina , Doenças Uterinas , Adulto , Endométrio/diagnóstico por imagem , Endométrio/cirurgia , Feminino , Humanos , Menstruação , Gravidez , Células-Tronco , Adulto Jovem
7.
Zhongguo Zhong Yao Za Zhi ; 44(24): 5479-5487, 2019 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-32237398

RESUMO

Ginseng has effects in reinforcing vital energy,invigorating health effectively and relieving fatigue symptoms,and ginsenoside( GS) is the main component of its anti-fatigue effect. Totally 17 active components and 92 drug targets of ginseng compounds were screened from Traditional Chinese Medicine Systems Pharmacology; and 78 intersecting genes of diseases and drug targets were obtained based on R Language Technology. The protein-protein interaction( PPI) network was constructed by STRING 11. 0 software,and Matthews Correlation Coefficient( MCC) algorithm was used to screen core target genes. Gene ontology enrichment analysis and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis were used to analyze the major genes and their roles in regulatory networks. The results indicated that ginseng could regulate the core target genes,including AKT serine/threonine kinase( AKT1),interleukin-1ß,Toll-like receptor binding molecule 1( ICAM1),mitogen-activated protein kinase 8( MAPK8),AP-1 transcription factor subunit( JUN),transducer and activator of transcription 1( STAT1) and prostaglandin peroxidase synthase 2( PTGS2). It could participate in the functions of cytokine receptor binding,cell adhesion molecule binding and tumor necrosis factor receptor superfamily binding,and also regulate the signal pathways of tumor necrosis factor,interleukin 17 and c-type lectin receptor,so as to exert an anti-fatigue effect. Based on the results of network analysis,32 four-week-old male SPFACR mice were randomly divided into control group,low-dose ginsenoside group,middle-dose ginsenoside group and high-dose ginsenoside group. The corresponding drugs were administrated for 3 weeks. The results showed that GS could significantly up-regulate the expressions of STAT1 and AKT1( P<0. 01,P<0. 05),and downregulate the expressions of PTGS2 and JUN( P<0. 01). However,there was no significant effect on MAPK8,IL-1ß and ICAM1. Ginseng's anti-fatigue regulation network was constructed through network pharmacology,and the results were verified by experiments,in order to reveal the anti-fatigue mechanism of ginseng and provide scientific basis for its clinical application.


Assuntos
Fadiga/prevenção & controle , Ginsenosídeos/farmacologia , Panax/química , Extratos Vegetais/farmacologia , Animais , Regulação da Expressão Gênica , Ontologia Genética , Masculino , Camundongos , Distribuição Aleatória
8.
Qual Life Res ; 27(11): 2815-2822, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29974382

RESUMO

OBJECTIVES: In order to address the current deficiency of health utility evidence relevant for economic evaluations involving treatments for rheumatoid arthritis (RA) in the Chinese setting, this study aims to develop a mapping algorithm linking the Health Assessment Questionnaire (HAQ) and EQ-5D-5L in a Chinese population of patients with RA. METHODS: An estimation sample was obtained from a cross-sectional study that collected HAQ, the pain Visual Analogue Scale, and EQ-5D-5L in RA patients in two tertiary referral hospitals in China. Mapping algorithms were derived in this study using two alternative regression methods: the beta regression and a multivariate ordered probit regression. The internal validity of the mapping algorithms was assessed in each case by calculating predictive performance using a bootstrapping procedure. RESULTS: Of the several algorithms developed using these data, predictive performance was shown to be better when VAS pain was included as a predictor and when the multivariate ordered probit regression method was used, rather than the beta regression method. The algorithms developed were shown to be comparable, in terms of predictive performance, to existing mapping studies despite the small sample size of the estimation data. CONCLUSION: It is hoped that the availability of these algorithms will facilitate the development of cost-effectiveness studies evaluating RA treatments in the Chinese health care setting.


Assuntos
Algoritmos , Artrite Reumatoide/diagnóstico , Análise Custo-Benefício/métodos , Qualidade de Vida/psicologia , Adulto , Idoso , Artrite Reumatoide/economia , Artrite Reumatoide/patologia , Povo Asiático , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Inquéritos e Questionários
9.
BMC Cancer ; 17(1): 878, 2017 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-29268703

RESUMO

BACKGROUND: Prostate is susceptible to infection and pro-inflammatory agents in a man's whole life. Chronic inflammation might play important roles in the development and progression of prostate cancer. Mesenchymal stem cells (MSCs) are often recruited to the tumor microenvironment due to local inflammation. We have asked whether stimulation of MSCs by pro-inflammatory cytokines could promote prostate tumor growth. The current study investigated the possible involvement of MSCs stimulated by pro-inflammatory cytokines in promotion and angiogenesis of prostate cancer through relative pathway in vitro and in vivo. METHODS: A syngeneic mouse model of C57 was established. The murine prostate cancer cells (RM-1) mixing with MSCs treated with tumor necrosis factor alpha (TNF-α) and interferon gamma (IFN-γ) or vehicle were subcutaneously injected into C57 mice. Tumor volume of C57 mouse model was estimated and serum level of platelet-derived growth factor (PDGF) and vascular endothelial growth factor (VEGF) was test by Enzyme-linked Immunosorbent Assay (ELISA). A hen egg test-chorioallantoic membrane (HET-CAM) assay was applied to test the effect of conditioned media of stimulated MSCs in chorioallantoic membrane angiogenesis. Short interfering RNA (siRNA) knocked down either hypoxia-inducible factor-1alpha (HIF-1α) or nuclear factor-erythroid-2-related factor 2 (NRF2) were employed. mRNA of PDGF and VEGF in MSCs, as well as NRF2 and HIF-1α was test by Real time polymerase chain reaction (PCR) analyses. Protein expression levels of PDGF and VEGF from conditioned medium, NRF2, HIF-1α, as well as PDGF and VEGF in MSCs were detected by Western blot analysis. RESULTS: MSCs treated with TNF-α and IFN-γ promote tumor growth in C57 syngeneic mouse model, correlating with increased serum level of PDGF, VEGF. HET-CAM assay shows the angiogenic effect of conditioned medium of MSCs pre-treated with the pro-inflammatory cytokines. mRNA and protein levels of two pro-angiogenic factors (PDGF and VEGF) and key hypoxia regulators (HIF-1α and NRF2) in MSCs were induced after MSCs' pretreatment. siRNA knockdown either HIF-1α or NRF2 results reduction of PDGF and VEGF expression. CONCLUSIONS: MSCs stimulated by pro-inflammatory cytokines increase the expression of PDGF and VEGF via the NRF2-HIF-1α pathway and accelerate prostate cancer growth in mice.


Assuntos
Indutores da Angiogênese/metabolismo , Medula Óssea/patologia , Citocinas/farmacologia , Mediadores da Inflamação/farmacologia , Células-Tronco Mesenquimais/patologia , Neoplasias da Próstata/patologia , Animais , Apoptose/efeitos dos fármacos , Medula Óssea/efeitos dos fármacos , Medula Óssea/imunologia , Medula Óssea/metabolismo , Proliferação de Células/efeitos dos fármacos , Galinhas , Membrana Corioalantoide/efeitos dos fármacos , Membrana Corioalantoide/patologia , Meios de Cultivo Condicionados/farmacologia , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Masculino , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/imunologia , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/metabolismo , Neoplasias da Próstata/induzido quimicamente , Neoplasias da Próstata/imunologia , Neoplasias da Próstata/metabolismo , Carga Tumoral , Células Tumorais Cultivadas , Microambiente Tumoral
10.
Nanotechnology ; 27(39): 395704, 2016 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-27561004

RESUMO

In this report, we describe a method for modifying electrical and optoelectrical properties of CdS nanobelts using low-energy (lower than 10 keV) e-beam irradiation in a scanning electron microscope. The electrical conductivity of the nanobelts was dramatically improved via the irradiation of e-beams. The modified conductivity of the nanobelts depends on the energy of the e-beam; it exhibits a larger photocurrent and higher external quantum efficiency but slower time-response than that before the modification. A possible mechanism about the modification is the increase of electron accumulation (injected electrons) in the nanobelts due to e-beam irradiation. In addition, the optoelectrical modification could be caused by the trapped electrons in the nanobelts and the decrease of contact resistance between the nanobelts and metal electrodes induced by e-beam irradiation. The results of this work are significant for the in situ study of semiconductor nanostructures in the electron microscope. Besides, the method of electrical and optoelectrical modification presented here has potential application in electronics and optoelectronics.

11.
J Reconstr Microsurg ; 32(9): 675-682, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27454181

RESUMO

Background Conventional angiography is an invasive technique. Submillimeter computed tomography angiography (CTA) has been shown to be an effective alternative for peripheral artery branches. This study aimed to assess the use of CTA to guide the choice and design of foot donor area for finger or thumb reconstruction. Methods This was a retrospective study of 79 patients who underwent finger or thumb reconstruction between January, 2011 and March, 2014. All these patients underwent preoperative CTA to determine the exact blood supply at the donor site. Preoperative imaging and intraoperative findings at the donor site were compared. Results Among the 79 patients (158 feet), 474 artery segments (dorsalis pedis artery [DPA], first dorsal metatarsal artery [FDMA], and toe web artery [TWA]) were evaluated using CTA. Image satisfaction rates of the vessels were 100.0 ± 0.0%, 89.2 ± 3.2%, and 60.1 ± 5.0% for DPA, FDMA, and TWA, respectively. Among the 158 feet, 90 were Gilbert type I (57.0%), 52 were Gilbert type II (32.9%), 13 were Gilbert type III (8.2%), and 3 were with poor visibility and could not be classified (1.9%). In all 79 patients, the CTA image of the FDMA was consistent with the intraoperative observations. All reconstructed fingers survived. Follow-up was available for 69 patients. After a 6- to 18-month follow-up, the reconstructed fingers and donor area recovered well, and the reconstructed fingers had strong holding power, without pain. Conclusion CTA can produce three-dimensional images for extremity arteries, allowing the preoperative assessment of blood supply and planning of donor site.


Assuntos
Angiografia por Tomografia Computadorizada , Dedos/irrigação sanguínea , Traumatismos da Mão/cirurgia , Procedimentos de Cirurgia Plástica , Cuidados Pré-Operatórios , Lesões dos Tecidos Moles/cirurgia , Polegar/irrigação sanguínea , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Dedos/cirurgia , Traumatismos da Mão/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Lesões dos Tecidos Moles/patologia , Retalhos Cirúrgicos , Polegar/cirurgia , Dedos do Pé/irrigação sanguínea , Adulto Jovem
12.
J Reconstr Microsurg ; 31(5): 369-77, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25785654

RESUMO

BACKGROUND: Microsurgical toe-to-hand transplantation is a reasonable salvage procedure after failed replantation, though no consensus exists on proper donor toe length for restoration of hand function and optimal donor flap needed for recipient site healing. The purpose of this study was to introduce a novel technique for preoperative planning in complicated toe-to-hand reconstruction and to assess feasibility in four cases. METHODS: Computed tomography (CT) angiography was used to map donor site vasculature, whereas CT data were used to create three-dimensional (3D) soft tissue and skeletal models for injured and uninjured hands. Based on the reformatted model (mirror of uninjured hand), soft tissue and finger skeleton models were generated using a 3D printer. An adhesive plaster model was placed on the donor site to determine osteotomy level and incision markings. The skeletal model was used to determine the length of the donor foot resection. Four complex amputation cases were included to illustrate clinical feasibility and early functional and cosmetic outcomes. RESULTS: In all four cases, thumb and fingers were reconstructed successfully and all flaps survived. No arterial or venous thrombosis or major donor morbidity were observed. Functional and cosmetic outcomes were satisfactory with similarly satisfactory static two-point discrimination, key pinch and grip strength, and Michigan Hand Outcomes Questionnaire scores. CONCLUSION: This novel microsurgical toe-to-hand reconstruction methodology, as introduced in this study, showed promising functional and cosmetic outcomes. Application of this technique in complex hand injuries has the potential to increase surgical efficiency, minimize procedural morbidity, and improve reproducibility.


Assuntos
Angiografia/métodos , Traumatismos da Mão/cirurgia , Microcirurgia/métodos , Procedimentos de Cirurgia Plástica/métodos , Impressão Tridimensional , Dedos do Pé/transplante , Adulto , Amputação Traumática , Competência Clínica , Desenho Assistido por Computador , Traumatismos dos Dedos/cirurgia , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Tomografia Computadorizada por Raios X , Adulto Jovem
13.
Phys Chem Chem Phys ; 16(9): 4186-92, 2014 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-24452101

RESUMO

A three-dimensional (3D) porous graphene hollow sphere (PGHS) framework has been fabricated via a hard template method and used to anchor α-Ni(OH)2 nanoparticles with the size of about 4 nm through electrochemical deposition. It is found that a 3D PGHS framework can improve the capacitive performance of Ni(OH)2 effectively. In hybrid materials, α-Ni(OH)2 achieves the high specific capacitance of 2815 F g(-1) at a scan rate of 5 mV s(-1) and 1950 F g(-1) even at 200 mV s(-1) with a capacitance retention of about 70%, indicating that the α-Ni(OH)2-coated 3D PGHS framework exhibits high rate capability. The excellent performance of such hybrid material is believed to be due to the smaller size of Ni(OH)2 nanoparticles and the PGHS framework with large specific surface area promoting efficient electron transport and facilitating the electrolyte ions migration. These impressive results suggest that the composite is a promising electrode material for an efficient supercapacitor.

14.
BMJ Open ; 14(5): e078276, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38749687

RESUMO

OBJECTIVE: This study aimed to investigate the knowledge, attitude and practice (KAP) of poststroke depression (PSD) among patients with PSD and their family members. DESIGN: Web-based cross-sectional study. SETTING: This study was conducted in Heilongjiang Province between October 2022 and April 2023. PARTICIPANTS: Patients with PSD and their family members. PRIMARY AND SECONDARY OUTCOME MEASURES: KAP scores. METHOD: The self-administered questionnaire comprised demographic characteristics, knowledge dimension, attitude dimension and practice dimensions. RESULTS: A total of 489 valid questionnaires were collected, with the average age of the subjects was 54.68±13.80 years, and including 258 (53.09%) patients who had a stroke. The mean scores for KAP were 6.36±2.66 (possible range: 0-10), 29.07±5.18 (possible range: 8-40) and 37.50±8.49 (possible range: 10-50), respectively. Concerning KAP scores, no differences were found between patients with PSD and their family members. Multivariate logistic regression analysis showed that retirement (OR=0.29, 95% CI 0.11 to 0.77, p=0.012) and monthly income less than ¥2000 (OR=0.46, 95% CI 0.27, 0.79, p=0.005) were independently associated with adequate knowledge. Knowledge (OR=2.12, 95% CI 1.44 to 3.14, p<0.001) was independently associated with positive attitude. Knowledge (OR=3.85, 95% CI 2.53 to 5.86, p<0.001) and attitude (OR=1.62, 95% CI 1.06 to 2.47, p=0.024) were independently associated with proactive practice. CONCLUSION: Patients and their family members had insufficient knowledge, positive attitude and moderate practice towards PSD. Retirement and low monthly income were associated with insufficient knowledge, while knowledge was associated with positive attitude and proactive practice.


Assuntos
Depressão , Família , Conhecimentos, Atitudes e Prática em Saúde , Acidente Vascular Cerebral , Humanos , Estudos Transversais , Masculino , Feminino , Pessoa de Meia-Idade , China , Acidente Vascular Cerebral/psicologia , Acidente Vascular Cerebral/complicações , Família/psicologia , Depressão/etiologia , Inquéritos e Questionários , Idoso , Adulto , Modelos Logísticos
15.
ACS Biomater Sci Eng ; 10(4): 2414-2425, 2024 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-38446137

RESUMO

Bone defects are a common and challenging orthopedic problem with poor self-healing ability and long treatment cycles. The difficult-to-heal bone defects cause a significant burden of medical expenses on patients. Currently, biomaterials with mechanical stability, long-lasting action, and osteogenic activity are considered as a suitable way to effectively heal bone defects. Here, an injectable double network (DN) hydrogel prepared using physical and chemical cross-linking methods is designed. The first rigid network is constructed using methylpropenylated hyaluronic acid (HAMA), while the addition of chitosan oligosaccharide (COS) forms a second flexible network by physical cross-linking. The mesoporous silica nanoparticles (MSN) loaded with bone morphogenetic protein-4 (BMP-4) were embedded into DN hydrogel, which not only enhanced the mechanical stability of the hydrogel, but also slowly released BMP-4 to achieve long-term skull repair. The designed composite hydrogel showed an excellent compression property and deformation resistance. In vitro studies confirmed that the HAMA/COS/MSN@BMP-4 hydrogel had good biocompatibility and showed great potential in supporting proliferation and osteogenic differentiation of mouse embryo osteoblast precursor (MC3T3-E1) cells. Furthermore, in vivo studies confirmed that the DN hydrogel successfully filled and closed irregular skull defect wounds, effectively promoted bone regeneration, and significantly promoted bone repair compared with the control group. In addition, HAMA/COS/MSN@BMP-4 hydrogel precursor solution can quickly form hydrogel in situ at the wound by ultraviolet light, which can be applied to the closure and repair of wounds of different shapes, which provides the new way for the treatment of bone defects.


Assuntos
Hidrogéis , Nanopartículas , Camundongos , Animais , Humanos , Hidrogéis/farmacologia , Hidrogéis/química , Osteogênese , Dióxido de Silício/farmacologia , Proteína Morfogenética Óssea 2/química , Proteína Morfogenética Óssea 2/farmacologia , Crânio/cirurgia , Crânio/lesões , Nanopartículas/química
16.
Adv Mater ; 36(28): e2312566, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38630368

RESUMO

Transition metal oxides (TMOs) are widely studied for loading of various catalysts due to their low cost and high structure flexibility. However, the prevailing close-packed nature of most TMOs crystals has restricted the available loading sites to surface only, while their internal bulk lattice remains unactuated due to the inaccessible narrow space that blocks out most key reactants and/or particulate catalysts. Herein, using tunnel-structured MnO2, this study demonstrates how TMO's internal lattice space can be activated as extra loading sites for atomic Ag in addition to the conventional surface-only loading, via which a dual-form Ag catalyst within MnO2 skeleton is established. In this design, not only faceted Ag nanoparticles are confined onto MnO2 surface by coherent lattice-sharing, Ag atomic strings are also seeded deep into the sub-nanoscale MnO2 tunnel lattice, enriching the catalytically active sites. Tested for electrochemical CO2 reduction reaction (eCO2RR), such dual-form catalyst exhibits a high Faradaic efficiency (94%), yield (67.3 mol g-1 h-1) and durability (≈48 h) for CO production, exceeding commercial Ag nanoparticles and most Ag-based electrocatalysts. Theoretical calculations further reveal the concurrent effect of such dual-form catalyst featuring facet-dependent eCO2RR for Ag nanoparticles and lattice-confined eCO2RR for Ag atomic strings, inspiring the future design of catalyst-substrate configuration.

17.
Dalton Trans ; 51(43): 16522-16526, 2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36239711

RESUMO

A luminescent 56-metal Cd(II)-Sm(III) nanocluster (1, molecular sizes: 4.5 × 2.7 × 2.7 nm) was constructed from a flexible Schiff base ligand, and its crystal structure was determined using the X-ray diffraction method. It shows a rapid triple-emissive response to 2,6-dichloro-4-nitroaniline (DCN, a common pesticide) with high sensitivity and selectivity, which can be used to quantitatively analyze the DCN concentrations in fruit extracts. The limits of detection (LODs) of 1 to DCN for the visible ligand-centered and Sm(III) emissions and NIR Sm(III) luminescence are from 0.95 µM to 2.81 µM.


Assuntos
Praguicidas , Praguicidas/análise , Cádmio/química , Ligantes , Cristalografia por Raios X
18.
ACS Nano ; 16(12): 21618-21625, 2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36521057

RESUMO

Octahedral molecular sieves (OMSs) based on MnO2 have been widely studied in the fields of deionization, geochemistry, and energy storage due to their microporous tunnel framework capable of adsorbing and exchanging various ions, particularly cations. The understanding of cation adsorption/exchange within OMS tunnels demands atomic-scale exploration, which has been scarcely reported. Here, we disclose how various cations (K+/Ag+/Na+) interplay within the OMS tunnel space on an atomic scale. Not only are the lattice sites for each adsorbed cation species pinpointed but the scenario of dual-cation adsorption within single tunnels is also demonstrated, together with the discovery of characteristic concentration-dependent cation ordering. Moreover, compared with the theoretical parent tunnel phase, the heterogeneous tunnels, though sparsely distributed, exhibit a distinct yet orderly cationic accommodation, highlighting the non-negligible role of tunnel heterogeneity in regulating OMS physiochemistry. Our findings clarify the long-existing ambiguities in nano- and atomic-scale science of the ion adsorption process in OMS materials and are expected to inspire their structural/compositional engineering toward functionality enhancement in various fields.

19.
Talanta ; 231: 122421, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-33965010

RESUMO

Peroxynitrite (ONOO-) is a series of basic biological oxidants involved in physiological and pathological processes. The detection of ONOO- in biological systems has been challenging due to its extremely short half-life and low steady-state concentration. In this work, a ratiometric fluorescent nanoprobe for ONOO- was constructed by coupling covalently of graphene quantum dots (GQDs) with cyanine 5.5 (Cy5.5). This nanoprobe (GQD-Cy5.5) could selectively accumulate in mitochondrial, appears two strong fluorescence emission peaks at 520 and 694 nm. In the presence of ONOO-, the intensity of fluorescence emission peak at 520 nm increased and the intensity of fluorescence emission peak at 694 nm decreased. The ratio (F520 nm/F694 nm) of fluorescence intensity at two emission peaks had a good linear relationship with the concentration of ONOO- in the range of 0-6.0 µM, and the detection limit was 0.03 µM. The excellent properties of the nanoprobe enable its applications in the ratiometric fluorescence imaging of endogenous ONOO- in cell mitochondria.


Assuntos
Ácido Peroxinitroso , Pontos Quânticos , Corantes Fluorescentes , Mitocôndrias , Imagem Óptica
20.
Open Med (Wars) ; 16(1): 1642-1652, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34761115

RESUMO

We explore miR-150-5p in atherosclerosis (AS). The AS model was constructed using Apo E-/- mice with an injection of the miR-150-5p mimic or an inhibitor. Pathological characteristics were assessed using Oil red O staining and Masson staining. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and Western blot were used to analyze the expressions of microRNA-150-5p (miR-150-5p), STAT1, α-SMA (α-smooth muscle actin) and proliferating cell nuclear antigen (PCNA). Targetscan and dual-luciferase reporter assay were used to analyze the interaction between miR-150-5p and STAT1. The viability, migration, cell cycle and α-SMA and PCNA expressions in oxidized low-density lipoprotein (ox-LDL)-stimulated primary human aortic smooth muscle cells (ASMCs) were assessed using molecular experiments. miR-150-5p was reduced in both AS mice and ox-LDL-stimulated human aortic smooth muscle cells but STAT1 had the opposite effect. The miR-150-5p inhibitor alleviated the increase of lipid plaque and reduced collagen accumulation in the aortas during AS. Upregulation of α-SMA and PCNA was reversed by miR-150-5p upregulation. STAT1 was targeted by miR-150-5p, and overexpressed miR-150-5p weakened the ox-LDL-induced increase of viability and migration abilities and blocked cell cycle in ASMCs, but overexpressed STAT1 blocked the effect of the miR-150-5p mimic. This paper demonstrates that miR-150-5p has potential as a therapeutic target in AS, with plaque stabilization by regulating ASMC proliferation and migration via STAT1.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA