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1.
Materials (Basel) ; 16(7)2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37049226

RESUMO

Bamboo is a material with excellent development prospects. It is increasingly used in furniture, decoration, building, and bridge construction. In this study, Furfurylated bamboo bundles and phenol-formaldehyde resin were used to make bamboo-scrimber composites (BSCs) via molding-recombination and hot-pressing processes. The effects of the impregnation mode, furfuryl-alcohol concentration, and curing temperature on the various physical-mechanical properties and durability of the composites were evaluated. Scanning-electron microscopy (SEM) was used to observe the microstructural differences. Fourier-transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) were employed to investigate changes in the chemical constituents. The heat resistance was also investigated using thermogravimetric analysis. The results showed that the density of the furfurylated BSC increased by up to 22% compared with that of the BSC-C with the same paving mode. The furfurylated BSCs had lower moisture contents: the average moisture content of the furfurylated BSCs was 25~50% lower than that of the BSC-C. In addition, the furfurylated BSCs showed better dimensional stability and durability, since the decay-resistance grade of the BSCs was raised from decay resistance (class II) to strong decay resistance (class I). In terms of the mechanical properties, the furfurylation had a slight negative effect on the mechanical strength of the BSCs, and the modulus of rupture (MOR) and horizontal shear strength (HSS) of the BSCs were increased to a certain extent under most of the treatment conditions. In particular, the highest HSS for indoor use and MOR of the furfurylated BSCs increased by 21% and 9% compared with those of the untreated BSCs, respectively. The SEM results indicated that the FA resin effectively filled in the bamboo-cell cavities and vessels, and the modified bamboo-parenchyma cells were compressed more tightly and evenly. The FTIR and XPS spectroscopy showed that the hydroxyl group of carboxylic acid of the bamboo-cell-wall component reacted with that of the furan ring, and the cellulose and hemicellulose underwent acid hydrolysis to a certain extent after the furfurylation. Overall, the present study highlights the potential of furfurylation as a modification method to enhance BSC products. Further research should focus on improving the ability of furfurylated BSCs to prevent the growth of Botryodiplodia theobromae. Additionally, the influence of furfuryl-alcohol resin on the bonding strengths of PF adhesives should be further clarified.

2.
Oxid Med Cell Longev ; 2022: 3050007, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35651730

RESUMO

Purpose: To observe and compare the efficacy of modified trabeculectomy (TE), Ahmed drainage valve implantation (AGV), and EX-PRESS glaucoma shunt for refractory glaucoma (RG). Methods: The study population of this retrospective study comprised 73 patients (76 eyes) who were suffering from RG and treated with modified TE, AGV, and EX-PRESS glaucoma shunt in our hospital from October 2012 to October 2020. The number of cases who underwent modified TE, AVG, and EX-PRESS glaucoma shunt was 36 (38 eyes). 19 (20 eyes), and 18 patients (18 eyes), respectively. The intraocular pressure (IOP), best-corrected visual acuity (BCVA), postoperative antiglaucoma medications, filter bubble morphology, anterior chamber depth (ACD), successful rate, and postoperative complications were recorded and statistically analyzed preoperative and 1 d, 1 w, 1 mon, 3 mon, 6 mon, and the end follow-up after operation. Results: The BCVA differed insignificantly among the three cohorts before and 6 months after surgery. Compared to preoperative BCVA, the postoperative BCVA of the three groups had no statistical significance. An obvious reduction in IOP was observed in all the three group after operation (P < 0.05). An obvious decrease in antiglaucoma medications was observed after surgery in all the three groups (P < 0.05). The AGV group showed deeper ACD postoperatively, while no marked difference was found in postoperative ACD in the other two groups. The total success rates in modified TE and AGV groups were slightly higher than those in the EX-PRESS group. The three groups differed insignificantly in filter bubble morphology after operation. Conclusion: Modified TE, AGV, and EX-PRESS glaucoma shunt showed equivalent efficacy for RG, which could validly reduce IOP and postoperative antiglaucoma medications. However, the success rates of modified TE and AGV were slightly higher than those of EX-PRESS glaucoma shunt in the last follow-up, and their complications were slightly less than those of the EX-PRESS glaucoma shunt.


Assuntos
Implantes para Drenagem de Glaucoma , Glaucoma , Trabeculectomia , Glaucoma/cirurgia , Humanos , Estudos Retrospectivos , Tonometria Ocular
3.
J Biomater Appl ; 36(2): 264-275, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34102913

RESUMO

Protein delivery systems have been extensively applied in controlled releasing of protein or polypeptides for therapeutic treatment or tissue regeneration. While 3 D printing technology shows great promise in novel dosage form with tailoring dose size and drug release profile, 3 D printable protein delivery system has to face many difficult challenges. In this study, we developed a hybrid suspension combining Eudragit polyacrylate colloid as matrix material and Pluronic polyether hydrogel as diffusion channel for protein release. This hybrid suspension can be 3 D-printed into construct with complex shape and inner structures thanks to its pseudoplastic and thixotropic rheological properties. The protein can be incorporated in hybrid suspension either in its original or nanoparticle capsulated form. The experiment shows that the protein release from construct is a function of drying time, molecular weight (MW) of chitosan, as well as their own structural/diffusional properties. Also, the theoretical derivation suggests polyacrylate matrix tortuosity, chitosan erosion rate as well as hydrogel diffusion coefficient all contributed to the extended duration of release profile. In addition, cytotoxicity test through cell culture confirmed that the construct fabricated from hybrid suspension exhibit relative good bio-compatibility. Finally, heterogeneous constructs with zoned design were fabricated as protein delivery system, which demonstrated the capability of hybrid suspension technique for spatial and temporal release of macromolecular drugs to realize pharmaceutical effectiveness or guild cell organization.


Assuntos
Materiais Biocompatíveis/química , Impressão Tridimensional , Proteínas/química , Animais , Becaplermina/química , Becaplermina/metabolismo , Materiais Biocompatíveis/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Quitosana/química , Coturnix , Hidrogéis/química , Nanopartículas/química , Poloxâmero/química , Proteínas/metabolismo , Reologia
4.
Can J Ophthalmol ; 56(5): 299-306, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33485841

RESUMO

OBJECTIVE: To analyze the rates of blindness with the demographics and clinical characteristics of patients with primary angle-closure disease (PACD) to provide a comprehensive epidemiologic reference in China. METHODS: A retrospective analysis was conducted in the Chinese Glaucoma Study Consortium database, which is a national multicenter glaucoma research alliance of 111 hospitals participating between December 21, 2015 and September 9, 2018. The diagnosis of PACD was made by qualified physicians through examination. Comparison of sex, age, family history, subtypes of PACD, and blindness were analyzed. RESULTS: A total of 5762 glaucoma patients were included, of which 4588 (79.6%) had PACD. Of PACD patients, 72.1% were female with the sex ratio (F/M) of 2.6, and the average age of patients was 63.8±9.3 years with the majority between 60 and 70 years. Additionally, 30% of these patients had low vision in one eye, 8.8% had low vision in both eyes, 1.7% had blindness in one eye, and 0.3% had blindness in both eyes. There were statistical differences with regards to age between male and female patients with PACD, with male patients being older on average. Primary angle-closure glaucoma was more commonly diagnosed in males (60%) compared to females (35.9%), whereas acute primary angle closure (APAC) was more commonly diagnosed in females (54.3%) compared to males (37.7%). The visual acuity in APAC patients was lower and the rate of low vision and blindness was higher than other subtypes. CONCLUSION: PACD was the major type of glaucoma in Chinese hospitals. There were more female patients with PACD, mostly between 60 and 70 years old, with higher rates of APAC in women. APAC resulted in the worst visual outcomes of all PACD subtypes.


Assuntos
Glaucoma de Ângulo Fechado , Baixa Visão , Idoso , Cegueira/diagnóstico , Cegueira/epidemiologia , Cegueira/etiologia , China/epidemiologia , Feminino , Glaucoma de Ângulo Fechado/diagnóstico , Glaucoma de Ângulo Fechado/epidemiologia , Humanos , Pressão Intraocular , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Baixa Visão/diagnóstico , Baixa Visão/epidemiologia
5.
International Eye Science ; (12): 2093-2096, 2017.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-669217

RESUMO

AIM:To investigate the clinical efficacy of pars plana vitrectomy and Baerveldt glaucoma implant(PPV-BGI) in the treatment of refractory glaucoma.METHODS:One hundred twenty-nine refractory glaucoma patient's clinical data from March 2013 to December 2015 that underwent PPV-BGI were retrospectively reviewed.Among them,63 eyes were neovascular glaucoma (NVG) and 69 eyes were other types of glaucoma (non-NVG).The changes of intraocular pressure(lOP),surgical results,visual acuity (VA),the number of glaucoma medications,complications,and the success rate of surgery were analyzed.RESULTS:Cumulative success rates for the NVG group and non-NVG group were 46.0% and 81.2%,respectively,within 1a after surgeries,the difference was significantly (P< 0.05).Preoperative lOP was 30.4 ± 10.2mmHg in the non-NVG group and 40.1±10.4mmHg in the NVG group,and lOP was reduced to 14.9±4.1mmHg in the non-NVG group and 17.8±4.9mmHg in the NVG,and the difference was significantly (P<0.05).Number of glaucoma medications decreased from 2.7 ± 1.2 in the non-NVG group and 2.9 ± 1.4 in the NVG group preoperatively to 0.51 ±0.96 in the non-NVG group and 0.96±1.18 in the NVG group,and the difference was significantly (P<0.05).Improvement in VA of in the NVG group and non-NVG group were observed in 14 eyes of 13 patients and 38 eyes and 37 patients respectively,and the difference was significantly (P<0.05).The postoperative complications of 1d and 1a follow-up in NVG group was significantly higher than non-NVG group (P<0.05).CONCLUSION:PPV-BGI is a viable surgical option for eyes with refractory glaucoma,but visual outcomes are frequently poor because of ocular comorbidities,especially in eyes with NVG.

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