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1.
Br J Ophthalmol ; 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33441322

RESUMO

BACKGROUND/AIMS: The primary objective is to quantify the lens nuclear opacity using swept-source anterior segment optical coherence tomography (SS-ASOCT) and to evaluate its correlations with Lens Opacities Classification System III (LOCS-III) system and surgical parameters. The secondary objective is to assess the diagnostic performance for hard nuclear cataract. METHODS: This cross-sectional study included 1222 patients eligible for cataract surgery (1222 eyes). The latest SS-ASOCT (CASIA-2) was used to obtain high-resolution lens images, and the average nuclear density (AND) and maximum nuclear density (MND) were measured by a custom ImageJ software. Spearman's correlations analysis was used to assess associations of AND/MND with LOCS-III nuclear scores, visual acuity and surgical parameters. The subjects were then split randomly (9:1) into the training dataset and validating dataset. Receiver operating characteristic curves and calibration curves were constructed for the classification on hard nuclear cataract. RESULTS: The AND and MND from SS-ASOCT images were significantly correlated with nuclear colour scores (AND: r=0.716; MND: r=0.660; p<0.001) and nuclear opalescence scores (AND: r=0.712; MND: r=0.655; p<0.001). The AND by SS-ASOCT images had the highest values of Spearman's r for preoperative corrected distance visual acuity (r=0.3131), total ultrasonic time (r=0.3481) and cumulative dissipated energy (r=0.4265). The nuclear density had good performance in classifying hard nuclear cataract, with area under the curves of 0.859 (0.831-0.886) for AND and 0.796 (0.768-0.823) for MND. CONCLUSION: Objective and quantitative evaluation of the lens nuclear density using SS-ASOCT images enable accurate diagnosis of hard nuclear cataract.

2.
Sci Total Environ ; 750: 141736, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32871374

RESUMO

Climate change is expected to increase extreme weather events, such as more extreme drought and rainfall incidences, with consequences for ecosystem carbon (C) cycling. An understanding of how drying and rewetting (DRW) events affect microbe-mediated soil processes is therefore critical to the predictions of future climate. Here, a reciprocal-transplant experiment was conducted using two soils originated from distinct climate and agricultural managements to evaluate how soil biotic and abiotic properties regulate soil respiration and its resilience to simulated DRW cycles. We found that regardless of the DRW intensity, the effects of microbial community on soil respiration and its resilience to DRW cycles were dependent on soil type. Soil microbial communities yielded higher respiration rates and resilience in native than foreign soils under both one and four DRW cycles, supporting the "home-field advantage" hypothesis. Structural equation modeling demonstrated that soil pH and total C directly influenced soil respiration, but effects of soil abiotic properties on respiration resilience were mediated by microbial communities. Among microbial drivers, the microbial C utilization capacity (as characterized by community-level physiological profile, C-acquisition enzyme activities and microbial metabolic quotients) was the best predictor of respiration resilience to DRW cycles, followed by microbial biomass carbon/nitrogen ratio and microbial community composition. Our study suggests that soil microbial communities may have adapted to their historical conditions, which facilitates the resilience of soil respiration to changing environments, but this adaptation may accelerate C loss from soils facing increasingly variable climate.


Assuntos
Ecossistema , Solo , Mudança Climática , Dessecação , Secas , Microbiologia do Solo
4.
Langmuir ; 2020 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-33283520

RESUMO

Silicone adhesives are widely used in many important applications in aviation, automotive, construction, and electronics industries. The mixture of (3-glycidoxypropyl)trimethoxysilane (γ-GPS) and hydroxy-terminated dimethyl methylvinyl co-siloxanol (DMMVS) has been widely used as an adhesion promoter in silicone elastomers to enhance the adhesion between silicone and other materials including polymers. The interfacial molecular structures of silicone elastomers and the adhesion promotion mechanisms of a γ-GPS-DMMVS mixture in silicone without a filler or an adhesion catalyst (AC) have been extensively investigated using sum frequency generation (SFG) vibrational spectroscopy previously. In this research, SFG was applied to study interfacial structures of silicone elastomeric adhesives in the presence of a silica filler and/or a zirconium(IV) acetylacetonate adhesion catalyst at the silicone/polyethylene terephthalate (PET) interface in situ nondestructively to understand their individual and synergy effects. The interfacial structures obtained from the SFG study were correlated to the adhesion behavior to PET. The interfacial reactions of methoxy and epoxy groups of the adhesion promoter were found to play significant roles in enhancing the interfacial adhesion of the buried interface. This research provides an in-depth molecular-level understanding on the effects of a filler and an adhesion catalyst on the interfacial behavior of the adhesion promotion system for silicone elastomers as well as the related impact on adhesion.

5.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(6): 2017-2021, 2020 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-33283735

RESUMO

OBJECTIVE: To investigate the types and proportion of gene mutations of thalassemia in Hakka people in Gannan Area of Jiangxi, and to provide some references for prevention and treatment of thalassemia major, genetic counseling and epidemiological studies. METHODS: 81 cases Hakka patients with severe thalassemia admitted treated in First Affiliated Hospital of Gannan Medical College from January 2009 to June 2019 were enrolled. The deletion type of α-thalassemia was detected by Gap-PCR. The point mutations of α-thalassemia and ß-thalassemia were detected by PCR-RDB. The thalassemia gene was detected and analyzed in the patients with anemia, and the frequency of gene mutation was calculated. RESULTS: Among 81 Hakka patients with thalassemia major, 4 ß-thalassemia (homozygote) genotypes were detected out, including: CD41-42(TTCT)(19 cases), ß-IVS-II-654 (C→T) (9 cases), -28M (A→G) (1 case), CD17 (A→T) (1 case); 12 ß-thalassemithalassemia (heterozygote) genotypes were detected out, including: CD41-42(-TTCT)/ß-IVS-II-654(C→T) (15 cases, 29.41%), ß-IVS-II-654(C→T)/ß-28M(A→G) (13 cases,25.49%) ; CD41-42(-TTCT)/ß-28M(A→G) (9 cases,17.65%); ß-IVS-II-654(C→T) /CD27/28(+C) (3 cases, 5.88%) ; CD41-42(-TTCT)/CD27/28(+C)(3 case,5.88%);ß-28M(A→G)/CD17(A→T) (2 cases,3.92%);CD41-42(-TTCT)/CD17(A→T), CD41-42(-TTCT)/Βe, ß-IVS-II-654(C→T)/ß-29、ßCD17(A→T)/CD71-72(+a), ßCD71-72/ß-28M(A→G), ß-28M(A→G) /ß-IVS-II-654(C→T)(1 cases,1.96%). There were 3 cases of ß homozygous thalassemia with α-thalassemia gene and 5 cases of ß heterozygotes thalassemia with α-thalassemia gene. CONCLUSION: The incidence rate of thalassemia in Hakka people in Gannan Area of Jiangxi is relatively high. The distribution of gene mutation types is as follows: the genotype of CD41-42 (-TTCT) is the main genotype of ß-thalassemia (homozygous); the major genotypes of ß- thalassemia (heterozygotes) are CD41-42 (-TTCT)/ß-IVS-II-654 (C→T) and ß-IVS-II-654 (C→T) /ß-28M (A→G); CD41-42 (-TTCT) gene is dominant in ß-complex α-thalassemia.

6.
Arch Pharm (Weinheim) ; : e2000063, 2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33184958

RESUMO

Isocitrate dehydrogenase 2 (IDH2) is a key enzyme in the regulation of cell metabolism. Its mutated type can lead to the accumulation of 2-hydroxyglutarate, which is often related to malignancies such as acute myeloid leukemia. Therefore, it is necessary to find new inhibitors targeting mutant IDH2. Discriminatory analysis-based molecular docking was employed to screen the ChemDiv compound library, which resulted in the identification of three new IDH2R140Q inhibitors with moderate-to-good IC50 values. Among them, compounds 1 and 3 displayed good selectivity against other mutant or wild-type IDH proteins. The most potent compound 1, bearing the [1,2,4]triazolo[1,5-a]pyrimidin scaffold, was subjected to dynamic simulations to provide more information on the binding mode with IDH2R140Q , providing structural clues to further optimize compound 1 as a new mutant IDH2 inhibitor.

7.
Artigo em Inglês | MEDLINE | ID: mdl-33127558

RESUMO

BACKGROUND & AIMS: The functions of the liver and the intestine are closely tied in both physiological and pathologic conditions. The gut microbiota (GM) often cause deleterious effects during hepatic pathogenesis. Autophagy is essential for liver homeostasis, but the impact of hepatic autophagy function on liver-gut interaction remains unknown. Here we investigated the effect of hepatic autophagy deficiency (Atg5Δhep) on GM and in turn the effect of GM on the liver pathology. METHODS: Fecal microbiota were analyzed by 16S sequencing. Antibiotics were used to modulate GM. Cholestyramine was used to reduce the enterohepatic bile acid (BA) level. The functional role of fibroblast growth factor 15 (FGF15) and ileal farnesoid X receptor (FXR) was examined in mice overexpressing FGF15 gene or in mice given a fibroblast growth factor receptor-4 (FGFR4) inhibitor. RESULTS: Atg5Δhep causes liver injury and alterations of intestinal BA composition, with a lower proportion of tauro-conjugated BAs and a higher proportion of unconjugated BAs. The composition of GM is significantly changed with an increase in BA-metabolizing bacteria, leading to an increased expression of ileal FGF15 driven by FXR that has a higher affinity to unconjugated BAs. Notably, antibiotics or cholestyramine treatment decreased FGF15 expression and exacerbated liver injury. Consistently, inhibition of FGF15 signaling in the liver enhances liver injury. CONCLUSIONS: Deficiency of autophagy function in the liver can affect intestinal environment, leading to gut dysbiosis. Surprisingly, such changes provide an adaptive protection against the liver injury through the FGF15-FGFR4 signaling. Antibiotics use in the condition of liver injury may thus have unexpected adverse consequences via the gut-liver axis.

8.
Microbiome ; 8(1): 142, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33008469

RESUMO

BACKGROUND: The soil mycobiome is composed of a complex and diverse fungal community, which includes functionally diverse species ranging from plant pathogens to mutualists. Among the latter are arbuscular mycorrhizal fungi (AMF) that provide phosphorous (P) to plants. While plant hosts and abiotic parameters are known to structure AMF communities, it remains largely unknown how higher trophic level organisms, including protists and nematodes, affect AMF abundance and community composition. RESULTS: Here, we explored the connections between AMF, fungivorous protists and nematodes that could partly reflect trophic interactions, and linked those to rhizosphere P dynamics and plant performance in a long-term manure application setting. Our results revealed that manure addition increased AMF biomass and the density of fungivorous nematodes, and tailored the community structures of AMF, fungivorous protists, and nematodes. We detected a higher abundance of AMF digested by the dominant fungivorous nematodes Aphelenchoides and Aphelenchus in high manure treatments compared to no manure and low manure treatments. Structural equation modeling combined with network analysis suggested that predation by fungivorous protists and nematodes stimulated AMF biomass and modified the AMF community composition. The mycorrhizal-fungivore interactions catalyzed AMF colonization and expression levels of the P transporter gene ZMPht1;6 in maize roots, which resulted in enhanced plant productivity. CONCLUSIONS: Our study highlights the importance of predation as a key element in shaping the composition and enhancing the biomass of AMF, leading to increased plant performance. As such, we clarify novel biological mechanism of the complex interactions between AMF, fungivorous protists, and nematodes in driving P absorption and plant performance. Video Abstract.

9.
Acta Otolaryngol ; : 1-4, 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33063573

RESUMO

BACKGROUND: There are many reports on the role of the malleus handle in ossicular chain reconstruction (OCR). However, the effect of the presence of the malleus handle is not clear. AIM/OBJECTIVES: To compare the hearing outcomes of using a partial ossicular replacement prosthesis (PORP) to reconstruct the ossicular chain under otoendoscopy with and without a malleus handle. METHODS: Records of 57 patients requiring OCR were retrospectively analyzed. They were divided into the malleus handle-present group (group 1) and the malleus handle-absent group (group 2). The audiometric results were analyzed pre- and postoperatively. A postoperative air-bone gap (ABG)≤20 dB was considered successful. RESULTS: The mean improvement in air conduction hearing thresholds was 19.80 dB in group 1 and 16.70 dB in group 2. The mean ABG improvement was 18.09 ± 12.79 dB for group 1 and 17.20 ± 16.44 dB for group 2. The malleus handle-present group achieved higher success (65.63%) than the malleus handle-absent group (52%; p> .05). CONCLUSIONS AND SIGNIFICANCE: Improvements in hearing outcomes were similar for the two groups. However, the malleus handle-present group showed a better reconstruction success rate. Our results suggest that if there is no lesion in the malleus handle, it is recommended to be retained.

10.
Front Pharmacol ; 11: 571156, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33013412

RESUMO

Background: COVID-19 is a type of pneumonia caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection that was identified in December 2019. Corticosteroid therapy was empirically used for clinical treatment in the early stage of the disease outbreak; however, data regarding its efficacy and safety are controversial. The aim of this study was to evaluate the efficacy and safety of corticosteroid therapy in patients with COVID-19. Methods: The PubMed, Cochrane Library, EMBASE, Web of Science, China National Knowledge Infrastructure (CNKI), Wanfang, and China Science and Technology Journal (VIP) databases were searched for studies. Data on clinical improvement, mortality, virus clearance time, adverse events (AEs), utilization of mechanical ventilation, length of intensive care unit (ICU) hospitalization, and hospital stay were extracted by two authors independently. Study quality was assessed by the Newcastle Ottawa Scale (cohort studies). The pooled data were meta-analyzed using a random effects model, and the quality of evidence was rated using the GRADE approach. Results: Eleven cohort studies (corticosteroid group vs control group), two retrospective cohort studies (without control group), and seven case studies were identified. A total of 2840 patients were included. Compared with the control treatments, corticosteroid therapy was associated with clinical recovery (RR = 1.30, 95% CI [0.98, 1.72]) and a significantly shortened length of ICU hospitalization (RR = -6.50; 95% CI [-7.63 to -5.37]), but it did not affect the mortality ((RR = 1.59; 95% CI [0.69-3.66], I2 = 93.5%), utilization of mechanical ventilation (RR = 0.35; 95% CI [0.10, 1.18]), duration of symptoms (WMD = 1.69; 95% CI [-0.24 to 3.62]) or virus clearance time (RR = 1.01; 95% CI [-0.91 to 2.92], I2 = 57%) in COVID-19 patients. Treatment with corticosteroids in patients with COVID-19 may cause mild adverse outcomes. The quality of evidence was low or very low for all outcomes. Conclusion: The findings of our study indicate that corticosteroid therapy is not highly effective, but it appears to improve prognosis and promote clinical recovery in patients with severe COVID-19.

11.
Exp Eye Res ; 200: 108207, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32866532

RESUMO

Claudin-3, an integral component of tight junction, has recently been shown to be expressed in retinal ganglion cells, retinal pigment cells, and retinal vascular endothelial cells. However, the role of claudin-3 in the development of the neural retina and its vessels remains undefined. This study aimed to investigate the role of zebrafish claudin-h (cldnh), the closest ortholog of mouse and human claudin-3, in the development of the neural retina and its vessels. Cldnh levels in green fluorescent protein transgenic zebrafish were genetically manipulated by cldnh morpholino oligonucleotide (MO) and cldnh mRNA to investigate gene function. The expression of cldnh was analyzed using polymerase chain reaction and immunofluorescence staining. The altered morphological, cellular and molecular events in the cldnh MO-morphant eyes were detected using hematoxylin-eosin staining, fluorescent dye injection, confocal in vivo imaging, BrdU labeling, TUNEL assay, RNA sequencing, and Western blot. We demonstrated that the cldnh protein was expressed in the neural retina and the hyaloid vessel which is the predecessor of the retinal vessel in zebrafish. Cldnh knockdown delayed lamination of the neural retina and reduced its thickness, which might be associated with the downregulation of the retinal development-related genes of atoh7, pcdh17, crx, neurod1, insm1a, sox9b and cdh11, and the upregulation of the cell cycle and apoptosis-associated genes of tp53, cdkn1a and casp8. Cldnh knockdown also reduced the density and interrupted the lumenization of the hyaloid vessels, which might be owing to the downregulation of the vessel formation-related genes of hlx1 and myl7. In conclusion, cldnh was required for the normal development of the neural retina and its vessels in zebrafish, providing a basis for elucidating its role in the pathogenesis of retinal vascular or inflammatory diseases.

12.
Langmuir ; 36(38): 11349-11357, 2020 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-32870007

RESUMO

Nylon and maleic anhydride (MAH)-grafted polyolefin-based thin co-extruded multilayer films are widely used in packaging applications encountered in daily life. The molecular structure of the nylon/MAH-grafted polyolefin buried interface and molecular bonding between these two chemically dissimilar layers are thought to play an important role in achieving packaging structures with good adhesion. Here, the molecular bonds present at a nylon/maleic anhydride (MAH)-grafted polyethylene buried interface were systematically examined in situ for the first time using sum frequency generation (SFG) vibrational spectroscopy. The carbonyl stretching frequency region of the SFG spectra of a nylon/MAH-grafted polyethylene buried interface showed the presence of hydrolyzed MAH groups grafted to the polyethylene chain and very low levels of unreacted MAH enriched at the buried interface. The ability of SFG to detect these molecular species at the buried interface yields important understanding of the interfacial molecular structure and provides the basis for subsequent in situ studies of the bonding reaction between the grafted MAH and nylon directly at the interface. This understanding may guide the design of multilayer films with improved properties such as enhanced adhesion between polymer layers. The approach used in this study is general and is applicable to study the molecular characteristics of other buried interfaces of significance, such as buried interfaces involving polymers in solar cells, polymer semiconductors, and batteries. Nylon impact modification is another area of interest where the interaction between the MAH-grafted elastomer and the continuous phase of nylon is important.

13.
Drug Des Devel Ther ; 14: 3663-3672, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32982173

RESUMO

Purpose: To explore the exact mechanism through which emodin down-regulates the migration and invasion abilities of endometrial stromal cells. Moreover, to explore the theoretical basis of emodin in the treatment of endometriosis. Patients and Methods: Endometriosis endometrial stromal cells (EESs) were cultured from 15 women with endometriosis and control endometrial stromal cells (CESs) were cultured from 12 women without endometriosis. The levels of proteins were evaluated by Western blot. The migration and invasion abilities of cells were detected by transwell assays. Results: The abilities of migration and invasion of EESs were much stronger than those of CESs. After treated with emodin, the migration and invasion abilities of EESs and CESs were significantly down-regulated, and the levels of integrin-linked kinase (ILK) and p-GSK-3ß were statistically down-regulated in EESs. Besides that, the expression of keratin was up-regulated while the expression of vimentin, ß-catenin and slug were all down-regulated by emodin in a dose- and time-dependent manner. Silencing of ILK gene in EESs also achieved the above effects, which were strengthened by emodin. Conversely, exogenous expression of ILK in CESs increased the expression of p-GSK-3ß, which were abrogated by emodin. Furthermore, SB216763 increased migration and invasion abilities of CESs by facilitating the epithelial-mesenchymal transition (EMT) through up-regulating levels of p-GSK-3ß, ß-catenin and slug, which were also abrogated by emodin. Conclusion: Emodin inhibits the migration and invasion abilities of human endometrial stromal cells by reversing the EMT via ILK/GSK-3ß pathway. So, emodin may be considered as a promising targeted therapy for endometriosis.

14.
Tissue Cell ; 66: 101394, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32933717

RESUMO

High-conductance, voltage- and calcium-activated potassium channels (BKCa) and store-operated calcium channels (SOCs) are belong to K+ channels superfamily and calcium channels superfamily respectively. Since BKCa potassium channels can be activated by calcium ions, we set out to examine whether SOCs are coupled with BKCa and to probe the relationship of BKCa and SOCs. First, we proved that BKCa immunoprecipitated with Orai1, and confocal microscopy showed that BKCa co-localized with Orai1. Next, we mapped that the exact binding sites locate in the 350aa-371aa fragment of the first regulatory domain associated with K+ conduction (RCK1) and the 720aa-814aa fragment in the second regulatory domain associated with K+ conduction (RCK2) via GST-pull-down assays. Then, we showed, by calcium imaging that BKCa overexpression enhanced endogenous and exogenous store-operated calcium entry (SOCE) and this enhancement could be blocked by Orai1 knockdown. Finally, we proved that SOCE could enhance the activity of BKCa by patch-clamp. From these results we conclude that BKCa can form a positive feedback loop with SOCs, as the Ca2+ influx from SOCs can active BKCa, which can hyperpolarize the plasma membrane. In turn, the hyperpolarized membrane will form a higher electric potential difference and give more force, allowing Ca2+ influx via SOCs.

15.
Pain ; 2020 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-32947547

RESUMO

Cervical spondylosis (CS)-related neck pain is difficult to treat due to its degenerative nature. The aim of this nine-center, single-blinded, randomized controlled trial was to evaluate the efficacy of optimized acupuncture for CS-related neck pain. Participants who met the inclusion criteria were randomized to optimized, shallow, and sham acupuncture groups (1:1:1). The primary outcome was the change from baseline in the Northwick Park Neck Pain Questionnaire (NPQ) score at week 4. Participants were followed up until week 16. Of the 896 randomized participants, 857 received ≥1 intervention session; 280, 286, and 291 received optimized, shallow, and sham acupuncture, respectively. A total of 835 (93.2%) participants completed the study. At week 4, significant differences (P<0.001) were observed in the changes in NPQ scores between the optimized acupuncture group and both the shallow (7.72 [95% confidence interval {CI}, 5.57-9.86]) and sham acupuncture groups (10.38 [95%CI, 8.25-12.52]). The difference in the scores at week 16 between the optimized acupuncture group and the shallow (8.84 [95%CI, 6.34-11.34]) and sham acupuncture (10.81 [95%CI, 8.32-13.30]) groups were significant. The center effect indicated wide variability in the treatment effects (Cohen's d=0.01-2.19). Most SF-36 scores were higher in the optimized acupuncture group than in the other groups. These results suggest that 4-week optimized acupuncture treatment alleviates CS-related neck pain and improves the quality of life, with the effects persisting for minimum 3 months. Therefore, acupuncture can have positive effects on CS-related neck pain, although the effect size may vary widely.

16.
Ann Transl Med ; 8(15): 921, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32953721

RESUMO

Background: To identify the main determinants of intraocular lens (IOL) tilt and decentration after cataract surgery using a novel anterior segment optical coherence tomography (AS-OCT) method. Methods: Fifty-six patients who underwent phacoemulsification with IOL implantation in one eye were continuously enrolled in this cohort study. Axial length (AL) was measured with IOL Master 700. The tilt and decentration of patients' preoperative crystalline lenses and postoperative IOLs, as well as crystalline lens thickness (LT), were measured using AS-OCT before surgery and 1 week after surgery. Results: The mean tilt and decentration of the patients' preoperative crystalline lenses were 4.90°±1.81° and 0.21±0.02 mm, and the mean tilt and decentration of IOLs were 4.75°±1.66° and 0.21±0.02 mm, respectively. There were no significant differences in magnitude, direction of tilt, or decentration between crystalline lenses and IOLs. The strongest determinant of IOL tilt was preoperative crystalline lens tilt (R2=0.512, P<0.001), followed by AL (R2=0.154, P=0.003). Additionally, crystalline lens decentration and AL explained 54.6% of the variability in IOL decentration. AL was the factor most highly associated with IOL decentration (R2=0.332, P<0.001), rather than crystalline lens decentration (R2=0.214, P<0.001). Conclusions: The position of the preoperative crystalline lens and AL were the critical determinants of IOL tilt and decentration. The tilt and decentration of IOLs will be greater in patients with larger tilt and decentration of crystalline lenses, or shorter and longer AL.

17.
Anal Chem ; 92(20): 14145-14152, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-32972132

RESUMO

Chemical reactions are the most important phenomena in chemistry. However, chemical reactions at buried solid/solid interfaces are very difficult to study in situ. In this research, the chemical reaction between two solid polymer materials, a nylon film and a maleic anhydride (MAH) grafted poly(ethylene-octene) (MAHgEO) sample, was directly analyzed at the buried nylon/MAHgEO interface at the molecular level in real time and in situ, using surface and interface sensitive sum-frequency generation (SFG) vibrational spectroscopy. Disappearance of nylon signals indicated a chemical reaction between amine and hydrolyzed amide groups of nylon and MAH groups on the MAHgEO at the buried interface. The appearance of SFG signals from reaction products was also observed at the buried nylon/MAHgEO interface. The mechanism of the observed interfacial reaction was further analyzed. Temperature-dependent SFG experiments were performed to measure the activation energy of the interfacial reaction, enabling a comparison with that reported for the bulk materials. The interfacial chemical reaction between nylon and MAHgEO greatly improved the adhesion of these dissimilar materials. The detailed analysis of a chemical reaction between two polymers at the polymer/polymer buried interface underscores the utility of SFG as a powerful analytical tool to build understanding of buried interfaces and to accelerate the design of interfacial structures with desired properties.

18.
Artigo em Inglês | MEDLINE | ID: mdl-32855647

RESUMO

Eucommia ulmoides Oliv., a native Chinese plant species, has been used as a traditional Chinese medicine formulation to treat rheumatoid arthritis (RA), strengthen bones and muscles, and lower blood pressure. Various parts of this plant such as the bark, leaves, and flowers have been found to have anti-inflammatory properties. E. ulmoides has potential applications as a therapeutic agent against bone disorders, which were investigated in this study. In vitro, RA joint fibroblast-like synoviocytes (RA-FLS) were treated with different concentrations (0, 25, 50, 100, 200, 400, 800, and 1000 µg/mL) of E. ulmoides bark, leaf, and male flower alcoholic extracts (EB, EL, and EF, respectively) to determine their potential cytotoxicity. Tumor necrosis factor- (TNF-) α and nitric oxide (NO) levels in RA-FLS were quantified using enzyme-linked immunosorbent assay (ELISA). Furthermore, collagen-induced arthritis (CIA) rats were treated with EB, EL, EF, Tripterygium wilfordii polyglycoside (TG) or the normal control (Nor), and then ankle joint pathology, bone morphology, and serum and spleen inflammatory cytokine levels were evaluated. The results showed that, in RA-FLS, EB, EL, and EF were not cytotoxic; EB and EF reduced TNF-α supernatant levels; and EB, EL, and EF reduced NO levels. The results of in vivo experiments showed that EB, EL, and EF alleviated ankle swelling and joint inflammation, while all extracts diminished inflammatory cell infiltration, pannus and bone destruction, and bone erosion. All tested extracts inhibited interleukin- (IL-) 6, IL-17, and TNF-α mRNA in the spleen of CIA rats, while EB most effectively reduced osteoclasts and inhibited bone erosion. EF showed the most obvious inhibition of inflammatory factors and pannus. Thus, EB, EL, and EF may alleviate bone destruction by inhibiting inflammation.

19.
Ann Transl Med ; 8(14): 850, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32793694

RESUMO

Background: Ocular wavefront aberration is a crucial optical factor affecting retinal imaging. Internal aberrations contributed to compensation mechanism of ocular aberration. However, previous studies mainly focused on total and corneal higher order aberrations, and little is known about the profile of internal HOA (IHOA) in healthy subjects. Methods: Participants with healthy crystalline lenses were prospective enrolled. The root mean square (RMS) of IHOAs for a pupil diameter of 4 mm were measured with an iTrace aberrometer. Lenticular parameters were measured with a swept source anterior segment optical coherence tomography (AS-OCT). Regression analyses were used to determine factors associated with logarithmic IHOAs. Results: Sixty-six Chinese participants (132 eyes) ranging from 5 to 59 years were analyzed. Logarithmic IHOA was positively associated with axial length (AL) (coefficient =0.101, P=0.016), and negatively associated with ocular refraction (coefficient =-0.032, P=0.023). Logarithmic internal coma increased by 0.161/mm (P=0.016) as AL became longer and decreased by 0.081/diopter (P<0.001) as ocular refraction became hyperopic. Lens tilt (coefficient =-0.121, P=0.037), decentration (coefficient= 3.027, P=0.003), and radius of anterior lens surface curvature (RAL) (coefficient= 0.096, P=0.026) were associated with logarithmic internal trefoil. lens tilt was also associated with logarithmic internal spherical aberration (coefficient =-0.195, P=0.018) and second astigmatism (coefficient =-0.132, P=0.030). Binocularly, the extent of coma, trefoil was different, while that of spherical aberration, secondary astigmatism was consistent. The vectors of the same type of IHOAs were nearly paralleled. Conclusions: IHOAs are mainly affected by ocular refraction, RAL, lens tilt and decentration. Intraocular differences and directions of higher-order aberrations follow certain rules, and their effects on visual function warrant further study.

20.
Mol Vis ; 26: 517-529, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32818015

RESUMO

Purpose: Interleukin-6 (IL-6) is elevated in intraocular fluid from eyes with proliferative vitreoretinopathy (PVR), but the exact role of the cytokine is still unclear. We investigated the function and mechanism of IL-6 in retinal pigment epithelium (RPE) cell biology in vitro and in a mouse model in vivo. Methods: After treatment with various concentrations of IL-6, RPE cell proliferation was assessed with cell counting kit-8 (CCK-8) assay, and epithelial-mesenchymal transition (EMT) markers were evaluated using western blotting and immunofluorescent staining. The activation of JAK1/STAT3 signaling was determined with western blotting. Moreover, the effects of blockade of IL-6/JAK1/STAT3 signaling were investigated using pharmacological inhibitor S3I-201. For in vivo studies, the PVR model was induced with intravitreal injection of dispase/collagenase in wild-type and IL-6 knockout mice. The severity of PVR was evaluated with histological analysis. The expression of IL-6, gp130, and EMT markers was assessed with quantitative real-time PCR and western blotting. Results: IL-6 statistically significantly induced RPE cell proliferation and EMT in a dose-dependent manner in vitro, which was accompanied by rapid phosphorylation of JAK1 and STAT3. Blockade of the IL-6/JAK1/STAT3 pathway with S3I-201 apparently inhibited RPE proliferation and EMT. Furthermore, IL-6 and gp130 overexpression, and JAK1/STAT3 signaling hyperactivation were detected in the retinas of the wild-type mice at 1, 3, and 7 days after dispase/collagenase injection. Finally, we confirmed that IL-6 deficiency markedly alleviated mouse PVR development via inhibiting EMT. Conclusions: These findings indicate that IL-6 promotes PVR by inducing RPE proliferation and EMT via the JAK1/STAT3 signaling pathway. We provided new evidence that therapeutic strategies to block IL-6 may be beneficial for PVR.

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