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1.
Angew Chem Int Ed Engl ; 62(32): e202303290, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37132602

RESUMO

Cluster catalysts are attractive for their atomically precise structures, defined compositions, tunable coordination environments, uniform active sites, and their ability to transfer multiple electrons, but they suffer from poor stability and recyclability. Here, we report a general approach to the direct insolubilization of a water soluble polyoxometalate (POM) [{(B-α-PW9 O34 )Co3 (OH)(H2 O)2 (O3 PC(O)-(C3 H6 NH3 )PO3 )}2 Co]14- (Co7 ) and formation of a series of POM-based solid catalysts with the counter-cations Ag+ , Cs+ , Sr2+ , Ba2+ , Pb2+ , Y3+ , and Ce3+ . They exhibit improved catalytic activities for visible-light-driven water oxidation following the trend CsCo7 >SrCo7 >AgCo7 >CeIII Co7 >BaCo7 >YCo7 >PbCo7 . While CsCo7 exhibits mainly homogeneous catalysis, the others are predominantly heterogeneous catalysts. An optimal oxygen yield of 41.3 % and a high apparent quantum yield (AQY) of 30.6 % for SrCo7 is obtained, which is comparable to that of the parent homogeneous POM. Band gap structures, UV/Vis spectra, and real-time laser flash photolysis experiments collectively suggest that easier electron transfer from the solid POM catalyst to the photosensitizer promotes photocatalytic water oxidation performance. These solid POM catalysts exhibit good stability, which is directly confirmed by a combination of Fourier-transform infrared spectroscopy, electron microscopy, X-ray diffraction patterns, Raman spectroscopy, X-ray photoelectron spectroscopy, five cycles of tests, and poisoning experiments.

2.
BMC Ophthalmol ; 23(1): 54, 2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36750792

RESUMO

BACKGROUND: To examine the astigmatism characteristics and surgical outcomes in patients with unilateral severe congenital ptosis following frontalis suspension surgery. METHODS: We included 53 congenital ptosis patients who underwent frontalis suspension surgery in Hunan Children's Hospital. Each patient underwent a refractive examination before and after surgery to assess astigmatism. We also evaluated the effects and complications associated with the procedure. RESULTS: Degree of astigmatism in ptotic and fellow eyes was - 1.45 ± 0.59 D and - 0.66 ± 0.51 D before surgery. Ratio of severe astigmatism in ptotic and fellow eyes was 51.3 and 12.8%. The fellow eyes presented with with-the-rule astigmatism (WR; 71.8%) and against-the-rule astigmatism (AR; 20.5%) types, with no cases of oblique astigmatism (OA). Ptotic eyes demonstrated higher frequencies of AR (59.0%) and OA (10.2%) than did fellow eyes. Furthermore, the former showed increased astigmatism, followed by a gradual decrease at the 6-month, before significantly decreasing at the 1-year postoperatively. The ratio of postoperative AR and OA astigmatism cases in ptotic eyes decreased to 35.9 and 7.7% 1 month postoperatively. However, there was a postoperative increase in the WR ratio from 30.8 to 56.4% after 1 month. Kaplan-Meier survival analysis showed a success rate of 81.4% at 6 months and 62.9% at 12 months which was influenced by the following complications: suture reaction, epithelial keratopathy, infection and granuloma, lid lag, and recurrence. CONCLUSION: Monocular congenital ptosis could develop severe astigmatism and higher frequency of AR or OA, early surgery may ameliorate astigmatic amblyopia.


Assuntos
Ambliopia , Astigmatismo , Blefaroptose , Criança , Humanos , Astigmatismo/complicações , Ambliopia/etiologia , Blefaroptose/cirurgia , Refração Ocular , Resultado do Tratamento , Estudos Retrospectivos , Músculos Oculomotores/cirurgia
3.
Front Genet ; 13: 866246, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35719371

RESUMO

Background: Congenital cataract is one of the most common causes of blindness in children. A rapid and accurate genetic diagnosis benefit the patients in the pediatric department. The current study aims to identify the genetic defects in a congenital cataract patient without a family history. Case presentation: A congenital cataract patient with microphthalmia and nystagmus was recruited for this study. Trio-based whole-exome sequencing revealed a de novo variant (c.394delG, p.V132Sfs*15) in CRYGC gene. According to the American College of Medical Genetics and Genomics (ACMG) criteria, the variant could be annontated as pathogenic. Conclusion: Our findings provide new knowledge of the variant spectrum of CRYGC gene and are essential for understanding the heterogeneity of cataracts in the Chinese population.

4.
J Matern Fetal Neonatal Med ; 35(7): 1248-1257, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32264735

RESUMO

PURPOSE: To investigate the influence of polymorphisms in vascular endothelial growth factor (VEGF), tumor necrosis factor-α (TNF-α), and glutathione S-transferase Pi isoform (GSTP1) genes on retinopathy of prematurity (ROP) risk, we performed a Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)-compliant meta-analysis. METHODS: An exhaustive search was conducted in PubMed, Web of Science, and CNKI for genetic studies evaluating the relationship between VEGF (-460 T/C, +936 C/T, -634 G/C, and -2578 C/A), TNF-α (-308 G/A) and GSTP1 (Ile/Val) polymorphisms and ROP risk from inception until November 2019. Odds ratio (OR) with the 95% confidence interval (CI) were used for estimating combined effect size. The quality of the included studies was evaluated using the Newcastle-Ottawa Scale (NOS). RESULTS: A total of 14 studies met the inclusion criteria. The meta-analyses revealed that VEGF - 460 T/C was associated with ROP risk in the allele model (C vs. T, OR = 0.83, 95% CI: 0.74-0.94, POR=0.004), homozygous gene model (CC vs. TT, OR = 0.70, 95% CI: 0.54-0.91, POR=0.008), dominant gene model (CC + TC vs. TT, OR = 0.80, 95% CI: 0.67-0.95, POR = 0.012), and recessive gene model (CC vs. TC + TT, OR = 0.74, 95% CI: 0.59-0.94, POR = 0.014). However, we did not find significant differences in the genotype and allele distribution of VEGF + 936 C/T, -634 G/C, -2578 C/A, TNF-α - 308 G/A and GSTP1 Ile/Val polymorphisms, between ROP and control group (p > .05). CONCLUSIONS: VEGF polymorphism -460 T/C was associated with a lower ROP risk. Further research is warranted to investigate haplotype effects of VEGF polymorphisms on the risk of ROP.


Assuntos
Retinopatia da Prematuridade , Fator de Necrose Tumoral alfa , Alelos , Predisposição Genética para Doença , Glutationa S-Transferase pi/genética , Humanos , Recém-Nascido , Polimorfismo de Nucleotídeo Único , Retinopatia da Prematuridade/genética , Fatores de Risco , Fator de Necrose Tumoral alfa/genética , Fator A de Crescimento do Endotélio Vascular/genética
5.
Biochem Cell Biol ; 99(4): 414-423, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34319836

RESUMO

The microRNAs miR-17-5p and miR-20a-5p play important roles on angiogenesis; however, it is arguable whether they regulate the formation of retinal blood vessels in retinopathy of prematurity (ROP). We used a mouse model of oxygen-induced retinopathy (OIR) to simulate the development of retinas in mice suffering from ROP, and the expression levels of miR-20a-5p, miR-17-5p, hypoxia-inducible factor 1-alpha (HIF-1α), and vascular endothelial growth factor (VEGF) were measured by RT-qPCR and Western blotting. Cell proliferation, apoptosis, and angiogenesis in the OIR model mice were measured using MTT assays, flow cytometry, and Matrigel assays, respectively. The interaction between HIF-1α/VEGF and miR-20a-5p/miR-17-5p were further validated using dual-luciferase reporter assays, biotin-labeled RNA-pulldown, and RNA immunoprecipitation (RIP) assays. In our OIR model, retinal angiogenesis in the mice was associated with down-regulation of miR-20a-5p and miR-17-5p, as well as up-regulation of HIF-1α and VEGF. In addition, the miR-20a-5p and miR-17-5p inhibited cell proliferation and angiogenesis through regulating HIF-1α and VEGF in the retinal cells of the OIR model mice. Moreover, it was found that miR-20a-5p and miR-17-5p bind to HIF-1α and VEGF at the 3'UTR, and there was a combined effect between miR-20a-5p and miR-17-5p on the regulation of HIF-1α and VEGF. It is worth noting that miR-17-5p and miR-20a-5p can preferentially regulate HIF-1α, then act on VEGF, thereby affecting the angiogenesis associated with ROP.


Assuntos
MicroRNAs/genética , Neovascularização Patológica/patologia , Oxigênio/toxicidade , Neovascularização Retiniana/patologia , Retinopatia da Prematuridade/complicações , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Animais Recém-Nascidos , Apoptose , Proliferação de Células , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos C57BL , Neovascularização Patológica/etiologia , Neovascularização Patológica/metabolismo , Neovascularização Retiniana/etiologia , Neovascularização Retiniana/metabolismo , Retinopatia da Prematuridade/induzido quimicamente , Fator A de Crescimento do Endotélio Vascular/genética
6.
Artigo em Inglês | MEDLINE | ID: mdl-33630263

RESUMO

Eco-tourism has become increasingly popular in the postmodern era. However, the management of tourism waste remains a major challenge for tourist destinations worldwide. Here, a non-participatory survey was conducted in five famous scenic spots in Yarlung Zangbo Grand Canyon National Park in Motuo County, Tibet, to characterize the waste composition and the amount of average daily production per capita during sightseeing. In addition, interviews were conducted at 26 restaurants and 32 hotels in Motuo Town (the administrative center of Motuo County), and data on the composition and amount of average daily production per capita of waste generated by tourists during accommodation and meals were obtained. The total amount of tourism waste in Motuo County in 2018 was approximately 172,108.82 kg. Based on the data collected, an emergy analysis was applied to emergy calculations of the pollution and losses generated during two conventional and locally used tourism waste disposal methods. According to China's emergy to money ratio (EMR) of 2018, the emergy was converted into its monetary value. The theoretical ecological compensation standard for Motuo County was 4,293,568.99 CNY (equivalent to 648,830.20 USD), and the average ticket price for a single tourist was 18.87 CNY (equivalent to 2.85 USD) in the absence of government fiscal transfer payments. These findings should be utilized by local national park authorities to establish a market-oriented ecological compensation mechanism that is capable of alleviating environmental pressure.

7.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 39(9): 944-8, 2014 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-25269501

RESUMO

OBJECTIVE: To evaluate the oblique angle, diplopia and stereoacuity before and after rectus recession-suspension on posterior sclera surgery in patients with restrictive strabismus caused by thyroid associated ophthalmopathy (TAO). METHODS: Data from 18 patients (19 eyes) with restrictive strabismus caused by TAO, who underwent rectus recession-suspension on posterior sclera surgery from July 2010 to June 2013 in Xiangya Hospital, Central South University, were analyzed retrospectively. Eight patients (8 eyes) or 5 patients (5 eyes) with hypotropia were operated with inferior rectus recession or superior rectus recession. Two patients (2 eyes) with esohypertropia or 3 patients (4 eyes) with esotropia were operated with inferior rectus recession plus medial rectus recession or medial rectus recession. Two patients (1 hypotropia, 1 esotropia) underwent orbital decompression surgery before strabismus surgery. All patients were performed rectus recession-suspension on posterior sclera surgery, and the oblique angle, diplopia view and stereopsis test were examined before and after the operation. RESULTS: All patients were followed up for more than 6 months. The preoperative prism were 20(Δ)- 80(Δ) and postoperative prism were 2(Δ)-10(Δ). There was diplopia on the primary position before surgery in 16 patients. After surgery, the diplopia in 14 patients disappeared on the primary and 15° down gaze, and 2 patients had not diplopia on the primary position but residual diplopia on inferior field. Two patients had stereopsis before surgery, and the numbers of patients raised to 14 after surgery. Compared with pre-operation, changes of the above measured indexs in post-operation were significant difference (all P<0.05). CONCLUSION: The rectus recession-suspension on posterior sclera surgery is effective to improve oblique angle and diplopia in restrictive strabismus caused by TAO, which can improve patient's living quality.


Assuntos
Oftalmopatia de Graves/complicações , Procedimentos Cirúrgicos Oftalmológicos/métodos , Esclera/cirurgia , Estrabismo/cirurgia , Descompressão Cirúrgica , Diplopia , Humanos , Músculos Oculomotores/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Acuidade Visual
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