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1.
Int J Biol Macromol ; 264(Pt 1): 130357, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38395273

RESUMO

Natural polysaccharides and protein macromolecules are the important components of extracellular matrix (ECM), but individual component generally exhibits weak mechanical property, limited biological function or strong immunogenicity in tissue engineering. Herein, gelatin (Gel) was deposited to the stretched (65 %) chitosan (CS) hydrogel substrates to fabricate the polysaccharide-protein CS-Gel-65 % composite hydrogels to mimic the natural component of ECM and improve the above deficiencies. CS hydrogel substrates under different stretching deformations exhibited tunable morphology, chemical property and wettability, having a vital influence on the secondary structures of deposited fibrous Gel protein, namely appearing with the decreased ß-sheet content in stretched CS hydrogel. Gel also produced a more homogenous distribution on the stretched CS hydrogel substrate due to the unfolding of Gel and increased interactions between Gel and CS than on the unstretched substrate. Moreover, the polysaccharide-protein composite hydrogel possessed enhanced mechanical property and oriented structure via stretching-drying method. Besides, in vivo subcutaneous implantation indicated that the CS-Gel-65 % composite hydrogel showed lower immunogenicity, thinner fibrous capsule, better angiogenesis effect and increased M2/M1 of macrophage phenotype. Polysaccharide-protein CS-Gel-65 % composite hydrogel offers a novel material as a tissue engineering scaffold, which could promote angiogenesis and build a good immune microenvironment for the damaged tissue repair.


Assuntos
Quitosana , Quitosana/química , Hidrogéis/química , Gelatina/química , Alicerces Teciduais/química , Engenharia Tecidual
2.
Transl Androl Urol ; 12(5): 744-760, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37305643

RESUMO

Background: Urinary retention is a common complication after gynecological surgery. Clean intermittent catheterization has been reported to have a lower incidence of urinary tract infections compared to transurethral indwelling catheterization. This study conducted a systematic review of randomized controlled trials (RCTs) to compare the effects of these two catheterization techniques after gynecological surgery. Methods: We searched PubMed, EMBASE, Web of Science, Cochrane, China National Knowledge Infrastructure (CNKI), Wanfang Data, and Chinese Scientific Journal Database (VIP) for 227 articles comparing the effects of the above two catheterization methods on urinary tract infections and urethral function after gynecological surgery up to November 2022. Subsequently, the Cochrane tool for assessing the risk of bias was employed to assess the quality of the included literature. Meta-analysis was performed using Stata software, and the appropriate models were adopted to pool the effect sizes. Results: A total of 19 articles involving 1,823 patients were included. The results showed that clean intermittent catheterization could greatly minimize the risk of urinary tract infections [relative risk (RR) =0.24, 95% confidence interval (CI): 0.20 to 0.28], improve the recovery of bladder function (RR =1.51, 95% CI: 1.32 to 1.72), reduce residual urine volume (mL) [weighted mean difference (WMD) = -82.64, 95% CI: -108.32 to -56.96], and shorten the duration of catheter maintenance (days) (WMD =-3.14, 95% CI: -4.98 to -1.30) compared with indwelling catheterization. Subgroup and regression analyses revealed that clean intermittent catheterization could achieve a more favorable therapeutic effect in patients receiving cervical cancer surgeries than those receiving other conventional gynecological procedures. Conclusions: Clean intermittent catheterization can lower the incidence of urinary tract infections, reduce residual urine volume, shorten the duration of catheter maintenance, and improve bladder function recovery. Thus, it may be more effective in patients undergoing radical cervical cancer resection.

3.
Ann Palliat Med ; 12(3): 571-583, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37272020

RESUMO

BACKGROUND: Currently, more and more older people are inevitably facing the final stages of life and their need for end-of-life care is becoming more prominent. It is therefore important to understand in advance what older people expect from their approaching end-of-life care and attention. We conducted a meta-analysis to explore the influence of advance care planning (ACP) on end-of-life decision-making among older adults living in community settings and their family members. METHODS: We searched databases including PubMed, Embase, Cochrane Library, and Web of Science through 10 August 2022, to locate randomized controlled trials (RCTs) that investigated the effects of ACP on the end-of-life decision-making of community-dwelling elderly individuals and their family members. Studies we obtained from the databases were screened based on specific inclusion and exclusion criteria. The software Stata 15.0 was used for combining and analyzing data. RESULTS: A total of 8 RCTs were eligible for meta-analysis. They involved 1,292 community-dwelling elderly people. The meta-analysis results revealed the incidence of the following items among participants after the intervention of the ACP: cardiopulmonary resuscitation (CPR) [rate =26%, 95% confidence interval (CI): 11-41%], life-sustaining treatment (rate =12%, 95% CI: 6-18%), gastric gavage (rate =34%, 95% CI: 18-50%), mechanical ventilation (rate =34%, 95% CI: 14-54%), death at home (rate =7%, 95% CI: 3-12%), and death in hospital (rate =6%, 95% CI: 3-10%). The systematic review protocol was prespecified and registered in the international prospective register of systematic reviews (PROSPERO; CRD42022348900). CONCLUSIONS: According to current research, ACP is a promising treatment that can improve the end of life of elderly people living in the community and their families. However, considering the heterogeneity of the included studies, multi-center RCTs with high quality and larger sample sizes need to be conducted to confirm our conclusions.


Assuntos
Planejamento Antecipado de Cuidados , Assistência Terminal , Humanos , Idoso , Vida Independente , Família , Morte
4.
Diagnostics (Basel) ; 13(9)2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37174999

RESUMO

Cystic adenomyosis is a rare type of uterine adenomyosis, mainly seen in young women, which is often characterized by severe dysmenorrhea. The quality of life and reproductive function of young women could be affected by misdiagnosis and delayed treatment. At present, there are no universal guidelines and consensus. We report two cases of patients with cystic adenomyosis in juveniles treated with high-intensity focused ultrasound (HIFU) ablation. In the first case, magnetic resonance imaging (MRI) indicated a cystic mass of 2.0 cm × 3.1 cm × 2.4 cm in the uterus. After she underwent HIFU treatment, her pelvic MRI showed a mass of 1.1 × 2.4 cm in size, and her dysmenorrhea symptoms gradually disappeared. In the second case, a pelvic MRI indicated a 5.1 cm × 3.3 cm × 4.7 cm cystic mass in the uterus. After she underwent HIFU and combined four consecutive cycles of GnRH-a treatment, the lesion shrunk 1.2 cm ×1.4 cm × 1.6 cm, without dysmenorrhea. Simultaneously, the report reviewed 14 cases of juvenile cystic adenomyosis over the last ten years. HIFU or HIFU-combined drugs were safe and effective in treating juvenile cystic adenomyosis, but multicenter and prospective studies may be necessary to validate this in the future.

5.
Orthod Craniofac Res ; 26(4): 618-631, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36975738

RESUMO

OBJECTIVES: To analyse the morphometric changes in the anterior alveolar bone of both the maxilla and mandible after space closure and retention for 18-36 mo in adults and adolescents. MATERIALS AND METHODS: Forty-two subjects with 4 first premolars extracted followed by retracting anterior teeth were included and divided into two age groups: adult group (4 males, 17 females, mean age: 23.67 ± 5.29 y, treatment duration: 27.95 mo, retention duration: 26.96 mo, ANB: 4.8 ± 2.1, U1-L1: 117.2 ± 9.2, U1-PP: 120.2 ± 7.2, L1-MP: 99.2 ± 5.3) and adolescent group (6 males, 15 females, mean age: 11.52 ± 1.21 y, treatment duration: 26.18 mo, retention duration: 25.79 mo, ANB: 5.2 ± 2.1, U1-L1: 116.0 ± 8.6, U1-PP: 119.8 ± 4.9, L1-MP: 99.7 ± 4.9). Alveolar bone height and thickness of anterior teeth in both groups were measured using cone beam computed tomography (CBCT) imaging performed at the pretreatment (T1), posttreatment (T2) and retention phases (T3). One-way repeated-measure ANOVAs were performed to evaluate the alveolar bone changes. Voxel-based superimpositions were performed to measure the amount of tooth movement. RESULTS: After orthodontic treatment, the lingual bone height and thickness of both arches and the labial bone height of the mandible decreased significantly in both age groups (P < .05). Most of the labial bone height and thickness of the maxilla in both groups remained unchanged (P > .05). After retention, the lingual bone height and thickness increased significantly in both age groups (P < .05). The amounts of increased height ranged from 1.08 to 1.64 mm in adults and from 0.78 to 1.21 mm in adolescents, and the amounts of increased thickness ranged from 0.23 mm to 0.62 mm in adults and from 0.16 mm to 0.36 mm in adolescents. Obvious movements of the anterior teeth during retention were not found (P > .05). CONCLUSIONS: Although lingual alveolar bone loss occurred in adolescents and adults during orthodontic treatment, continuous remodelling occurred in the later retention phase, which provides a reference for clinical treatment planning of bimaxillary dentoalveolar protrusion.


Assuntos
Incisivo , Má Oclusão , Masculino , Feminino , Humanos , Adulto , Adolescente , Adulto Jovem , Criança , Estudos Retrospectivos , Dente Pré-Molar/diagnóstico por imagem , Maxila/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico
6.
Adv Wound Care (New Rochelle) ; 12(9): 498-512, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36355602

RESUMO

Objectives: Accelerating wound healing using continuous exogenous electrical stimulation is limited due to some serious side effects, including thermal damage. Many previous studies based on direct current contact stimulation may cause chemical burns or blisters, thereby increasing patients suffering. The aim of this study was to develop a safer and more convenient pulse capacitive coupling electrical field (PCCEF) stimulation to accelerate wound healing. Approach: A PCCEF-generating platform was self-designed to facilitate wound healing. The promoting effects and appropriate pulse width were explored by applying PCCEFs (54 mV/mm, 60 Hz) of different pulse widths to various cells involved in wound healing and mouse models for 2 h daily. Results: PCCEFs of ≥10 µs pulse width showed marked promotion of the migration and proliferation of human dermal fibroblasts and HaCaT cells, enhanced the M2-type polarization and YPA/TAZ expression of macrophages, and facilitated the wound healing of mouse models. Comprehensive histological results suggested that PCCEF of 100 µs pulse width exerted the most positive effects. Innovation: A safe and effective PCCEF was developed to promote wound healing, which prevented prolonged stimulation and averted direct contact. Conclusion: PCCEF accelerated wound healing, especially at the optimal 100 µs pulse width, and was expected to be translated to clinical application, helping alleviate patient suffering, while reducing side effects.


Assuntos
Pele , Cicatrização , Humanos , Proliferação de Células , Cicatrização/fisiologia , Pele/patologia , Fibroblastos/metabolismo , Neovascularização Patológica/metabolismo , Movimento Celular
7.
Front Cardiovasc Med ; 9: 847163, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35571218

RESUMO

Objective: Delayed enhancement cardiac CT is a reliable tool for the diagnosis of left atrial appendage thrombus but limited for scanning heterogeneity. We aimed to explore the improvement of the 1 and 3-min delay phase at the diagnostic level to detect left atrial appendage thrombus, in order to set up a reasonable CT scanning scheme. Materials and Methods: A total of 6,524 patients were continuously retrieved from January 2015 to September 2020 retrospectively. The patients had undergone Transesophageal echocardiography (TEE) and cardiac CT with complete period include the arterial enhancement phase, 1 and 3-min delay phase, TEE were used as the reference standard. The final study included 329 patients. Three experienced radiologists independently assessed each phase of the cardiac CT images for thrombus diagnosis. We explored the improvement of the diagnostic ability of different delayed contrast-enhanced phases for left atrial appendage thrombus detection. Multiple logistic regression analysis were used for further high-risk stratification to avoid an additional 1-min delayed scan. Results: In total, 29 thrombosis were detected at TEE. For all cardiac CT phases, sensitivity and negative predictive were 100%. The specificity were 0.54, 0.93, and 1.00, respectively; The positive predictive values (PPV) were 0.17, 0.57, and 1.00, respectively; Area under curve (AUC) were 0.75, 0.95, and 0.98, respectively. High risk factors that cannot be clearly diagnosed with 1-min delay phase included reduced cardiac function, increased CHA2DS2-VAScscore and left atrial enlargement. Compared with the arterial enhanced phase, increased radiation doses in the 1 and 3-min delay phases were 1.7 ± 1.3 msv and 1.5 ± 0.8 msv (mean ± standard deviation). Conclusion: Using TEE as the reference standard, early contrast-enhanced CT scanning with 1 and 3-min delay is necessary for the diagnosis of left appendage thrombus, which could significantly improve the diagnostic efficiency. Patients with high-risk stratification are suitable for direct 3-min delayed scanning.

8.
BMC Oral Health ; 22(1): 200, 2022 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-35606730

RESUMO

BACKGROUND: This study aimed to compare the age-related positional and morphological characteristics of the temporomandibular joint (TMJ) between individuals with anterior openbite or crossbite and controls. METHODS: This multi-cross-sectional comparative study analysed cone-beam computed tomography images of 750 participants, equally divided into the openbite, crossbite, and control groups (OBG, CBG, and CG, respectively). Each group was further divided into five subgroups (8-11 years, 12-15 years, 16-19 years, 20-24 years, and 25-30 years). Measurements of the TMJ included the position of the condyles in their respective fossae and morphology of the condyles and fossae. Data were submitted to statistical analysis. The study adhered to the STROBE Statement checklist for reporting of cross-sectional studies. RESULTS: Condyles were positioned more posteriorly with increasing age in all groups, and the condylar position was more posterior in the OBG than in the CBG. The articular eminence inclination increased with age in all the groups. There were significant differences in the articular eminence inclination among the three major groups at the age of > 15 years, and the condylar path was flatter in the CBG than in the OBG. CONCLUSIONS: Age-related morphological and positional characteristics of the TMJ differed considerably among OBG, CBG and CG. Contrary to CBG, OBG was found to have relatively posterior condylar position and steeper condylar path.


Assuntos
Má Oclusão , Mordida Aberta , Adolescente , Humanos , Tomografia Computadorizada de Feixe Cônico , Estudos Transversais , Côndilo Mandibular , Articulação Temporomandibular/diagnóstico por imagem
9.
Front Med (Lausanne) ; 9: 819122, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35308554

RESUMO

Background and Aims: Evidence on the association between irritable bowel syndrome (IBS) and colorectal cancer (CRC) risk is inconsistent. Therefore, we aimed to examine whether IBS leads to an increased risk for CRC using a systematic review and meta-analysis approach. Methods: PubMed, Embase, and Web of Science were systematically searched to identify all relevant literature published through July 30, 2021. The pooled risk ratios (RRs) and corresponding 95% confidence intervals (CIs) for CRC after diagnosis of IBS were computed using random-and fixed-effects models and stratified by age, follow-up time, gender, and study design. The quality of included studies was assessed by the Newcastle-Ottawa scale. Results: We included six studies consisting of 1,085,024 participants. Overall, the risk of detecting CRC after the initial IBS diagnosis was significantly higher than non-IBS controls (RR = 1.52, 95% CI: 1.04-2.22, P = 0.032). The peak of elevated risk occurred within the first year of IBS diagnosis (RR = 6.84, 95% CI: 3.70-12.65, P < 0.001), and after 1 year, the risk of CRC was similar to that of the general population (RR = 1.02, 95% CI: 0.88-1.18, P = 0.813). Notably, we found that the RR of CRC was more significant in IBS patients younger than 50 years compared to those older than 50 years (RR = 2.03, 95% CI: 1.17-3.53, P = 0.012 vs. 1.28, 95%CI: 0.94-1.75, P = 0.118, respectively). Gender and study design did not affect the results. Conclusion: The risk of CRC within one year of the initial IBS diagnosis was increased approximately six-fold, whereas the long-term risk was not increased. However, current evidence does not support that IBS leads to an increased incidence of CRC, and the early excess risk is more likely attributable to misclassification resulting from overlapping symptoms rather than causation. Clinicians must remain vigilant for the CRC risk in patients younger than 50 years with IBS-like symptoms to avoid delaying necessary screening.

10.
J Biomed Nanotechnol ; 18(1): 132-143, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35180906

RESUMO

Engineered myocardial tissue is expected to be used in the treatment of myocardial defects and other diseases, and one of the keys is to construct a suitable environment for the culture of myocardial tissue in vitro. In this study, flow shear stress and pulse electrical stimulation were applied to cardiomyocytes with a self-designed device by simulating the mechanical and electrical physiological microenvironment of myocardial tissue. The strength and duration of pulse electrical stimulation as well as the intensity of shear stress were studied in detail to optimize the experimental parameters. Concretely, 100 mV pulse electrical stimulation (1 Hz and 10 ms pulse width) and 10 dyn/cm² shear stress were used for studying the influence of combined mechanical-electrical stimulation to the growth of cardiomyocytes. The mechanical factor of the combined stimulation promoted the expression of α-cardiac actin mRNA, the electrical factor caused an increase in Cx-43 mRNA expression, and shear stress and pulse electrical stimulation showed a synergistic action on the expression of GATA-4 mRNA. It indicated that combined mechanical-electrical stimulation had a better effect on the functionalized culture of cardiomyocytes, which provided an important theoretical basis for the further construction of in vitro engineered myocardial tissue.


Assuntos
Miócitos Cardíacos , Engenharia Tecidual , Estimulação Elétrica , Miocárdio , Miócitos Cardíacos/fisiologia , Estresse Mecânico
11.
Orthod Craniofac Res ; 25(2): 174-182, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34320269

RESUMO

OBJECTIVES: To evaluate the morphometric changes in maxillary and mandibular anterior alveolar bone after orthodontic treatment and retention for 18-24 months by cone-beam computed tomography (CBCT). SETTING AND SAMPLE POPULATION: Thirty-four adolescent patients (12 males and 22 females; mean age: 14.29 ± 1.24 years) diagnosed with bimaxillary dentoalveolar protrusion and with extractions of the 4 first premolars were included. MATERIALS AND METHODS: The labial and lingual (palatal) alveolar bone thickness, height and root length of the maxillary and mandibular anterior teeth were assessed using CBCT imaging at the pre-treatment (T1), post-treatment (T2) and retention phases (T3). Voxel-based superimpositions of the T2 and T3 images were performed, and the distances of incisal and apical movement between T2 and T3 were measured to determine whether relapses occurred. RESULTS: After orthodontic treatment, the labial and lingual (palatal) bone height decreased significantly (P < .05) and the labial thickness at the crestal (L1), midroot (L2), and apical levels (L3) had no significant change, while the lingual (palatal) bone thickness at all three levels decreased significantly (P < .05). After 18-24 months of retention, the lingual (palatal) height and the lingual (palatal) thickness at the crestal (L1) level increased significantly (P < .05). There were no obvious incisal and apical movements of the anterior teeth between T2 and T3 (P > .05), indicating that no relapses occurred. CONCLUSIONS: Even though lingual (palatal) alveolar loss occurred due to the orthodontic treatment, the cervical alveolar bone seemed to recover over time. Therefore, appropriate camouflage treatment can be used in patients with bimaxillary dentoalveolar protrusion, and this treatment will not irreversibly deteriorate periodontal health and affect the orthodontic treatment stability.


Assuntos
Incisivo , Má Oclusão , Adolescente , Dente Pré-Molar/diagnóstico por imagem , Dente Pré-Molar/cirurgia , Tomografia Computadorizada de Feixe Cônico , Feminino , Humanos , Masculino , Má Oclusão/diagnóstico por imagem , Má Oclusão/terapia , Mandíbula , Maxila , Estudos Retrospectivos
12.
J Mater Chem B ; 9(37): 7821-7834, 2021 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-34586141

RESUMO

The dura mater is an essential barrier to protect the brain tissue and the dural defects caused by accidents can lead to serious complications. Various materials have been applied to dural repair, but it remains a challenge to perfectly match the structure and properties of the natural dura mater. Small intestinal submucosa has been developed for dural repair because of its excellent biocompatibility and biological activity, but its application is tremendously limited by the rapid degradation rate. Chitosan has also been broadly investigated in tissue repair, but the traditional chitosan hydrogels exhibit poor mechanical properties. A nanofiber chitosan hydrogel can be constructed based on an alkaline solvent, which is equipped with surprisingly high strength. Therefore, based on the bilayer structure of the natural dura mater, a biomimetic hierarchical small intestinal submucosa-chitosan sponge/chitosan hydrogel scaffold with a micro/nano structure was fabricated, which possessed a microporous structure in the upper sponge and a nanofiber structure in the lower hydrogel. The degradation rate was remarkably reduced compared with that of the small intestinal submucosa in the enzymatic degradation experiment in vitro. Meanwhile, the chitosan nanofibers brought high mechanical strength to the bilayer scaffold. Moreover, the hierarchical micro/nano structure and the active factors in the small intestinal submucosa have a fantastic effect on promoting the proliferation of fibroblasts and vascular endothelial cells. The bilayer scaffold showed good histocompatibility in the experiment of in vitro subcutaneous implantation in rats. Thus, the biomimetic hierarchical small intestinal submucosa-chitosan sponge/chitosan hydrogel scaffold with micro/nano structure simulates the structure of the natural dura mater and possesses properties with excellent performance, which has high practical value for dural repair.


Assuntos
Materiais Biomiméticos/química , Quitosana/química , Hidrogéis/química , Mucosa Intestinal/química , Nanoestruturas/química , Animais , Bandagens , Materiais Biomiméticos/farmacologia , Coagulação Sanguínea/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Humanos , Masculino , Porosidade , Próteses e Implantes , Ratos , Ratos Sprague-Dawley , Resistência à Tração
13.
Nanoscale Adv ; 3(18): 5393-5398, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36132642

RESUMO

Herein, ultra-stable quasi-two-dimensional perovskite quantum dots (quasi-2D PQDs) are synthesized by introducing the butylamine cation (BA+) into the methylamine lead bromide perovskite (MAPbBr3). By reducing the dimensionality of the perovskite structure, the quasi-2D perovskite (BA)2(MA) x-1Pb x Br3x+1 presents higher luminescence efficiency and better environmental stability than traditional 3D perovskites, which is mainly because the dimensionality-reduced perovskite has higher exciton binding energy and formation energy. Under an optimal MA : BA ratio of 1 : 1, the quasi-2D perovskite exhibits about four times higher luminescence efficiency (PLQY = 49.44%) than pristine MAPbBr3; meanwhile it emits stable luminescence in an environment with 80% humidity for 50 days. Most importantly, carbon quantum dot (CQD) doping has also been applied in this work, which effectively passivates the defects of (BA)2(MA) x-1Pb x Br3x+1 via H-bond interaction, further improving the stability of the perovskite in water. Inspired by the superior performances of the proposed quasi-2D nanomaterial, a novel colorimetric method based on halide ion exchange has been developed for H2O2 detection, which also demonstrates that PQDs show significant potential in the field of environmental monitoring.

14.
J Mater Chem B ; 8(21): 4660-4671, 2020 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-32374794

RESUMO

The composite hydrogel of gelatin (Gel) and oxidized sodium alginate (OSA) is often used in biomedical fields due to its good biocompatibility. However, the typical utility of borax and weak mechanical properties are not preferred either in the cell environment or as a supporting scaffold. Herein, poly(vinyl alcohol) (PVA) is mixed with Gel and OSA to construct a ternary hydrogel Gel-OSA-PVA so as to improve the mechanical properties and reduce toxicity. The hydrogel possessed tunable mechanical properties by adjusting the concentrations of PVA and the oxidized degrees of OSA, related closely to the dynamic imine bonds and multiple hydrogen bonds among these macromolecules. In terms of the effects of OSA, its aldehyde group content played a more important role in enhancing the compressive modulus of hydrogels compared to its change of molecular weight/chain length. These multiple dynamic bonds also endowed the Gel-OSA-PVA hydrogel with good self-healing performance. Interestingly, the hydrogels presented great conductivity due to the existence of free ions, varying with the deformation of hydrogels, and showed great potential in promoting osteogenesis. Together with the absence of cytotoxicity and antibacterial properties, the hydrogel is a potential candidate for applications in the biomedical field.


Assuntos
Alginatos/química , Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Gelatina/química , Hidrogéis/farmacologia , Álcool de Polivinil/química , Células 3T3 , Animais , Antibacterianos/química , Células Cultivadas , Hidrogéis/química , Camundongos , Estrutura Molecular , Tamanho da Partícula , Propriedades de Superfície
15.
J Biomed Nanotechnol ; 16(11): 1658-1666, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33461657

RESUMO

A number of bone repair materials are demanded due to bone injury in clinical treatment. Magnetic hydrogels combined with the magnetic field have showed great promoting potential in the field of bone regeneration. Considering the superiority of magnetic microspheres in magnetic localization and drug release, magnetic poly(lactic-co-glycolic acid) microspheres, obtained by electrospraying, were combined with gelatin hydrogel to construct a magnetic poly(lactic-co-glycolic acid) microsphere-gelatin hydrogel for bone repair in our study. Particularly, we investigated the combined effect of 20 mT static magnetic field and magnetic poly(lactic-co-glycolic acid) microsphere-gelatin hydrogel on the proliferation of MC3T3-E1 pre-osteoblasts, indicating that it could significantly promote cell growth at a low concentration of Fe3 O4. Furthermore, the hydrogel containing 400 mg˙ L-1Fe3 O4 presented the highest growth-promoting effect under a 20 mT static magnetic field. Therefore, the magnetic poly(lactic-co-glycolic acid) microsphere-gelatin hydrogel possesses impressive application value in promoting osteogenesis and bone repair.


Assuntos
Gelatina , Ácido Poliglicólico , Glicóis , Hidrogéis , Ácido Láctico , Campos Magnéticos , Fenômenos Magnéticos , Microesferas , Osteoblastos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico
16.
ACS Appl Mater Interfaces ; 11(37): 34348-34354, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31455081

RESUMO

Having suffered from intrinsic structural lability, perovskite quantum dots (PQDs) are extremely unstable under high-temperature and moisture conditions, which have greatly limited their applications. In this work, we propose a novel method to synthesize ultrastable carbon quantum dots (CQDs)-doped methylamine (MA) lead bromide PQDs with SiO2 encapsulation (CQDs-MAPbBr3@SiO2). The kernel CQDs-MAPbBr3 is formed by the interaction of carboxyl-rich CQDs with MAPbBr3 via H-bond, which greatly improves the thermal stability of CQDs-MAPbBr3. Furthermore, highly compact SiO2 encapsulates the proposed CQDs-MAPbBr3 via a facile in situ growth strategy, which effectively enhances the water resistance and air stability of CQDs-MAPbBr3@SiO2. As a result, the proposed nanomaterial shows extremely high water stability in aqueous solution for over 9 months and ideal thermal stability with strong fluorescence (FL) emission after 150 °C annealing. Based on the superior stability and ultrahigh FL efficiency of this proposed nanomaterial, a primary sensing method for ion (Ag+ and Zn2+) FL detection has been developed and the mechanism of PQDs-based ion determination has also been discussed, thus exhibiting the potential applications of CQDs-MAPbBr3@SiO2 in the area of FL assay and environment monitoring.

17.
Front Oncol ; 9: 1354, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31921627

RESUMO

This study aimed at estimating the effects of epidemiological risk factors for lung cancer in never-smokers. A multicenter and matched case-control study was conducted in the cities of Shijiazhuang, Xingtai, Qinhuangdao, Baoding, and Chengde in North China. It comprised 1,086 cases and 2,172 healthy subjects as controls, all of whom had smoked fewer than 100 cigarettes in their lifetimes. Patients were newly diagnosed with lung cancer between January 2015 and December 2017. Each patient was matched to two control participants for sex and age (±5 years). Both univariate analysis and multivariate conditional logistic regression models were used to estimate the odds ratio (OR) and 95% confidence interval (95% CI). Subsequently, data were stratified by participant sex and different air quality conditions for analysis. Type of job, exposure to environmental tobacco smoke in the workplace or at home, above-average exposure to cooking oil fumes, depression, poor sleep quality, occupational exposure, cardiovascular diseases, and family history of cancer were revealed as significant risk factors for lung cancer in never-smokers. However, higher educational level, frequent use of a PM2.5 mask, cooking using clean fuels, and consumption of dietary supplements and tea reduced the risk of lung cancer. Risk factors varied between males and females. In areas with air pollution, the number of risk factors was greater than elsewhere, and the magnitudes of their effects were different. Hence, focusing on these risk factors is important for the prevention and control of lung cancer in never-smokers.

18.
J Mater Chem B ; 6(30): 4952-4962, 2018 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32255068

RESUMO

Electrical stimulation (ES) and magnetic stimulation (MS) can promote bone tissue formation in vivo. Loading ES and MS simultaneously would be very beneficial for bone tissue construction in vitro or in vivo. Magnetic-conductive bi-functional scaffolds which are favorable for the transfer of ES and MS, could further facilitate bone cell/tissue growth. Poly(3,4-ethylenedioxythiophene) (PEDOT)/Fe3O4/polylactic acid-co-glycolic acid (PLGA) magnetic-conductive bi-functional fibrous scaffolds were prepared through in situ polymerization of EDOT on Fe3O4/PLGA fibers. MC3T3-E1 pre-osteoblasts were incubated on the PEDOT/Fe3O4/PLGA fibrous scaffolds and were stimulated by electrical, magnetic and electrical-magnetic signals respectively to detect the impact of different stimulation on cell viability. The measured results show that the scaffolds possess good conductivity and superparamagnetic responsiveness. Furthermore, both electrical and magnetic stimulation promoted cell proliferation and magnetic stimulation could induce cell alignment arrangement. Meanwhile, under electrical-magnetic double stimulation, cell viability was much higher than for cells under single electrical or magnetic stimulation. The growth promoting effects of PEDOT/Fe3O4/PLGA fibrous scaffolds under electrical-magnetic double stimulation has great practical potential for bone tissue engineering.

19.
ACS Appl Mater Interfaces ; 8(20): 12968-75, 2016 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-27145690

RESUMO

In this work, ceria doped ZnO nanomaterials with flower-structure (Ce:ZONFs) were prepared to construct a luminol-based electrochemiluminescence (ECL) immunosensor for amyloid-ß protein (Aß) detection. Herein, carboxyl groups (-COOH) covered Ce:ZONFs were synthesized by a green method with lysine as reductant. After that, Ce:ZONFs-based ECL nanocomposite was prepared by combining the luminophore of luminol and Ce:ZONFs via amidation and physical absorption. Luminol modified on Ce:ZONFs surface could generate a strong ECL signal under the assistance of reactive oxygen species (ROSs) (such as OH(•) and O2(•-)), which were produced by a catalytic reaction between Ce:ZONFs and H2O2. It was worth noticing that a quick Ce(4+) ↔ Ce(3+) reaction in this doped material could increase the rate of electron transfer to realize the signal amplification. Subsequently, the luminol functionalized Ce:ZONFs (Ce:ZONFs-Lum) were covered by secondary antibody (Ab2) and glucose oxidase (GOD), respectively, to construct a novel Ab2 bioconjugate (Ab2-GOD@Ce:ZONFs-Lum). The wire-structured silver-cysteine complex (AgCys NWs) with a large number of -COOH, which was synthesized by AgNO3 and l-cysteine, was used as substrate of the immunosensor to capture the primary antibody (Ab1). Under the optimal conditions, this proposed ECL immunosensor had exhibited high sensitivity for Aß detection with a wide linear range from 80 fg/mL to 100 ng/mL and an ultralow detection limit of 52 fg/mL. Meanwhile, this biosensor had good specificity for Aß, indicating that the provided strategy had a promising potential in the detection of Aß.


Assuntos
Peptídeos beta-Amiloides/análise , Técnicas Biossensoriais/métodos , Imunoensaio/métodos , Medições Luminescentes , Luminol/química , Nanopartículas Metálicas/química , Óxido de Zinco/química , Cério/química , Técnicas Eletroquímicas , Glucose Oxidase/metabolismo
20.
Biosens Bioelectron ; 71: 407-413, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-25950936

RESUMO

In this work, a novel and multifunctional nanocomposite of luminol capped gold modified Fe3O4 (Lu-AuNPs@Fe3O4) was utilized as the carrier of secondary antibody (Ab2) to fabricate a sandwiched electrochemiluminescence (ECL) immunosensor for ultrasensitive detection of mucin-1 (MUC1). Herein, the luminol capped gold nanoparticles (Lu-AuNPs) were synthesized with HAuCl4 and luminol by the help of NaBH4 at room temperature, and then Lu-AuNPs were adsorbed on the Fe3O4 magnetic nanoparticles (MNPs) to form the nanocomposite of Lu-AuNPs@Fe3O4 via electrostatic interaction. Fe3O4 MNPs in Lu-AuNPs@Fe3O4 exhibited excellent conductivity and admirable catalytic activity in H2O2 decomposition, which could enhance the ECL efficiency of luminol-H2O2 system. In addition, the substrates of gold coated ZnO nanoparticles (AuNPs@ZnO), providing large specific surface areas for primary antibody (Ab1) capturing, were modified on the electrode. As a result, a wide linear range of 7 orders of magnitude from 10 fg/mL to 10 ng/mL was obtained with an ultralow detection limit of 4.5 fg/mL for MUC1.


Assuntos
Condutometria/instrumentação , Imunoensaio/instrumentação , Medições Luminescentes/instrumentação , Luminol/química , Nanopartículas de Magnetita/química , Nanocompostos/química , Desenho de Equipamento , Análise de Falha de Equipamento , Ouro/química , Nanopartículas Metálicas/química , Mucina-1/imunologia , Nanocompostos/ultraestrutura , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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