Rockburst disaster is one of the prominent problems faced by deep underground engineering. Microseismic (MS) monitoring techniques can be used to warn of rockburst in tunnels to provide scientific ...basis for rock burst prevention and control measures. Described in this paper, is an MS monitoring system based on MS source location with hierarchical strategy implemented in the tunnel group of the Jinping II hydropower station in Sichuan Province, China. The spatiotemporal distribution of MS events was analyzed in the construction process and the size effect of rockburst risk discussed by statistical analysis and numerical calculation of rockburst in seven tunnels. The results show that the active period of microseisms and the high-incidence period of rockburst are within 1.5 h after the rock disturbance. The MS events within 1D from the tunnel wall are the most intensive and are mainly concentrated near the heading face, the side wall, and the left spandrel. At the construction site, the accuracy rate of rockburst prediction is 61.8%, of which the accuracy rate of the medium and strong rockburst is 80.3%. Based on field statistics of rockburst, the increase of the tunnel excavation section size can reduce the rockburst strength to a certain extent, which is consistent with the numerical simulation results.
Seed propagation is the main method of mulberry expansion in China, an important economic forest species. However, seed germination is the most sensitive stage to various abiotic stresses, especially ...salinity stress. To reveal the molecular regulatory mechanism of mulberry seed germination under salt stress, flavonoid metabolomics and transcriptomics analyses were performed on mulberry seeds germinated under 50 and 100 mmol/L NaCl stress. Analysis of the flavonoid metabolome revealed that a total of 145 differential flavonoid metabolites (DFMs) were classified into 9 groups, 40 flavonols, 32 flavones, 16 chalcones and 14 flavanones. Among them, 61.4% (89) of the DFMs accumulated continuously with increasing salt concentration, reaching the highest level at a 100 mmol/L salt concentration; these DFMs included quercetin-3-O-glucoside (isoquercitrin), kaempferol (3,5,7,4'-tetrahydroxyflavone), quercetin-7-O-glucoside, taxifolin (dihydroquercetin) and apigenin (4',5,7-trihydroxyflavone), indicating that these flavonoids may be key metabolites involved in the response to salt stress. Transcriptional analysis identified a total of 3055 differentially expressed genes (DEGs), most of which were enriched in flavonoid biosynthesis (ko00941), phenylpropanoid biosynthesis (ko00940) and biosynthesis of secondary metabolites (ko01110). Combined analysis of flavonoid metabolomic and transcriptomic data indicated that phenylalanine ammonia-lyase (PAL), 4-coumarate-CoA ligase (4CL), chalcone synthase (CHS), flavonol synthase (FLS), bifunctional dihydroflavonol 4-reductase/flavanone 4-reductase (DFR) and anthocyanidin reductase (ANR) were the key genes involved in flavonoid accumulation during mulberry seed germination under 50 and 100 mmol/L NaCl stress. In addition, three transcription factors, MYB, bHLH and NAC, were involved in the regulation of flavonoid accumulation under salt stress. The results of quantitative real-time PCR (qRT‒PCR) validation showed that the expression levels of 11 DEGs, including 7 genes involved in flavonoid biosynthesis, under different salt concentrations were consistent with the transcriptomic data, and parallel reaction monitoring (PRM) results showed that the expression levels of 6 key enzymes (proteins) involved in flavonoid synthesis were consistent with the accumulation of flavonoids. This study provides a new perspective for investigating the regulatory role of flavonoid biosynthesis in the regulation of mulberry seed germination under salt stress at different concentrations.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Fenofibrate, as a lipid-lowering drug, has been reported to have a protective effect on the retina independent with plasma lipid levels. This study aimed to investigate that the ameliorative effects ...of fenofibrate on systemic and retinal inflammation, as well as gut microbiota dysbiosis in high-fat diet (HFD)-induced mice. C57BL/6J mice were randomly allocated into four groups: standard diet (SD) group; HFD group; SD plus fenofibrate (SD_ Fe) group; HFD plus fenofibrate (HFD_ Fe) group. After successfully establishing models (5 months), indicators associated with lipid, gut barrier, inflammation and gut microbiota were investigated. Our results showed that supplementing the HFD with fenofibrate decreased body weight gain, alleviated dyslipidemia and reversed the downregulation of short-chain fatty acid (SCFAs) in serum, retina and feces. Fenofibrate ameliorated intestinal barrier function damage in HFD-induced mice. Fenofibrate coadministration inhibited the levels of inflammatory factor and lipopolysaccharide (LPS) in the serum and attenuated inflammatory response in the retina of HFD-induced mice. Systemic LPS was positively correlated with a series of inflammatory factors in serum and retina, respectively. Fenofibrate supplementation down-regulated the abundances of LPS-associated bacteria in HFD mice, including
Firmicutes
and
Proteobacteria
at the phylum level,
Desulfovibrionaceae
at the family level, as well as
unclassified_ Desulfovibrionaceae
,
Acetatifactor
,
Flavonifractor
,
Oscillibacter
and
Anaerotruncus
at the genus level. However, fenofibrate treatment up-regulated the abundances of SCFA-associated bacteria in HFD mice, including
Bacteroidetes
at the phylum level,
Porphyromonadaceae
at the family level, as well as
unclassified_Porphyromonadaceae
,
Barnesiella
,
Alloprevotella
and
Bifidobacterium
at the genus level. In conclusion, our results confirmed fenofibrate could attenuate HFD-induced systemic and retinal inflammation, accompanying with restoration of intestinal barrier damage and modulation of gut microbiota/metabolites. This work provided an explanation for the ameliorative effects of fenofibrate on HFD-induced systemic and retinal inflammation might be partially related with the modulation of gut microbiota and its metabolites.
Obtaining accurate axial length (AL) is very important for the establishment of animal models of myopia. The purpose of this study is to compare the accuracy of Quantel A-B scan, OD-1 A scan, and ...vernier caliper in measuring AL in Sprague Dawley (SD) rats.
In total, 60 5-week-old SD rats were divided into female rat group (
= 30) and male rat group (
= 30). Quantel A-B scan and OD-1 A scan were, respectively, used to measure the AL of both eyes of each living rat, and vernier caliper was used to measure the anterior-posterior diameter of each rat's eyeball. Besides, the correlation between refractive error (RE) and AL measured by different instruments was evaluated, and the accuracy of the three measurement methods was compared according to gender and left/right eyes.
There were significant differences in AL and diopter of SD rats at the same age (
< 0.05). the AL of male rats was greater than that of female rats, while diopter (D) was the opposite; There was no significant difference in AL and D between left and right eyes in the same SD rats (
> 0.05); There were statistical differences among the three measurement methods (
< 0.05), AL measured by vernier caliper was the largest, followed by Quantel A-B scan, OD-1 A scan; Difference in AL between male and female was not statistically significant between the results obtained by Quantel A-B scan and vernier caliper (
> 0.05), but there were statistically significant differences between the other two measurement methods (
< 0.05).
Sex is the influencing factor of AL and RE. Imaging measurement can accurately measure the AL in living small rodents. Compared with OD-1 A scan, Quantel A-B scan may be more accurate.
The aim of this study was to confirm the presence of the form deprivation myopia (FDM) guinea pig eye-gut axis and investigate the relationship between serum vasoactive intestinal peptide (VIP), ...lipopolysaccharides (LPS), specific gut microbiota and their metabolites.
20 specific-pathogen-free (SPF) guinea pigs were divided into the FDM and the control(Con) group. Following model induction, serum levels of VIP and LPS were quantified. A combination of 16S ribosomal ribosomal Ribonucleic Acid (rRNA) gene sequencing, non-targeted metabolomics and bioinformatics analysis were employed to identify disparities in gut microbiota and metabolites between the two groups of guinea pigs.
Compared to the control group, FDM guinea pigs exhibited a significant trend towards myopia, along with significantly elevated concentrations of LPS and VIP (p < 0.0001). Furthermore, Ruminococcus_albus emerged as the predominant bacterial community enriched in FDM (p < 0.05), and demonstrated positive correlations with 10 metabolites, including l-Glutamic acid, Additionally, Ruminococcus_albus exhibited positive correlations with VIP and LPS levels (p < 0.05).
The findings suggest that the Ruminococcus_Albus and glutamate metabolic pathways play a significant role in myopia development, leading to concurrent alterations in serum VIP and LPS levels in FDM guinea pigs. This underscores the potential of specific gut microbiota and their metabolites as pivotal biomarkers involved in the pathogenesis of myopia.
Background. To report the outcomes of phacoemulsification combined with vitrectomy in eyes with extreme myopia (-30 diopters or more). Case Presentation. Three patients with cataract, vitreous ...opacities, and extreme myopia of more than -30 diopters underwent a combined surgical procedure of cataract extraction combined with vitrectomy. Postoperative refractive correction of the three cases ranged from -1.0 D to -2.5 D spherical equivalent. There was an obvious hyperopic shift of all cases. All patients noted a significant improvement in uncorrected and best-corrected visual acuity from 0.4 to 0.8 in case 1, from CF/70 cm to 1.0 in case 2, and from 0.12 to 0.5 in the right eye and 0.15 to 0.2 in the left eye in case 3. Vitreous floaters disappeared in all cases. No complications were noted during follow-up. Conclusions. To the best of the authors’ knowledge, these represent the first reported clinical cases of combined cataract extraction+vitrectomy surgery in eyes with extreme (>-30 D) myopia. Our results support the notion that phacoemulsification combined with vitrectomy may be a good therapeutic option for cataracts and vitreous floaters in cases with extreme myopia.
Myopia is a common chronic eye disease, this study is to investigate the effects of exogenous retinoic acid (RA) on intraocular parameters, especially choroidal thickness (CT) and retinal thickness ...(RT), in guinea pigs with form deprivation myopia (FDM).
A total of 80 male guinea pigs were divided randomly into 4 groups: Control, FDM, FDM + RA, and FDM + Citral groups. The FDM + RA group was given 24 mg/kg RA dissolved in 0.4 mL peanut oil; the FDM + Citral group was given citral 445 mg/kg dissolved in 0.4 mL peanut oil; The other two groups were given 0.4 mL peanut oil. After 4 weeks, the refractive error (RE), axial length (AL), and intraocular pressure (IOP) of all guinea pigs were measured, and the parameters of RT and CT were obtained using enhanced depth imaging optical coherence tomography (EDI-OCT).
After 4 weeks, both the RE and AL in the FDM and FDM + RA groups were increased, and the RT and CT in both groups were smaller than those in the Control group (
< 0.05). Only the IOP of the right eye in the FDM + RA group increased significantly (
< 0.05). The RT of the right eye of the 4 groups was compared: Control group > FDM + Citral group > FDM group > FDM + RA group. Compared with the RT of the left eye and the right eye among the 4 groups, the RT of the right eye in the FDM and FDM + RA groups was significantly less than that in the left eye (
< 0.05). Moreover, the CT of the right eye in the Control group was greater than that in the other three groups (
< 0.0001). There was no significant difference in the CT among the FDM, FDM + RA, and FDM + Citral groups (
> 0.05). In contrast to the RT results, the CT results of the left and right eyes in the FDM + Citral group showed statistically significant differences (
< 0.05).
RA participates in the progression of FDM as a regulatory factor. Exogenous RA can increase the RE, AL, and IOP of FDM guinea pigs, and might aggravate the retinal thinning of FDM guinea pigs. Citral can inhibit these changes, but RA might not affect the thickness of the choroid.
The ventilation effect has a direct influence on the efficiency and security of the construction of an underground cavern group. Traditional forced ventilation schemes may be ineffective and result ...in resource wastage. Based on the construction ventilation of the Jinzhou underground oil storage project, an axial flow gallery ventilation mode using shafts as the fresh air inlet was proposed. A 3D steady RANS (Reynolds Averaged Navier-Stokes) approach with the RNG (Renormalization-group) k-ε turbulence model was used to study airflow behavior and hazardous gas dispersion when different ventilation schemes were employed. Field test values of the air velocity and CO concentration in the main cavern and construction roadway were also adopted to validate the RNG k-ε turbulence model. The results showed that the axial flow gallery ventilation mode can ensure that the direction of air flow is the same as that of heavy trucks, fresh air is always near the excavation face, and the disturbance of the construction process is greatly reduced. The scheme is suitable for large-scale caverns with a ventilation distance less than 2 km, and an intermediate construction shaft is not needed. When the ventilation distance exceeds 2 km, it is possible to use jet fans to assist the axial flow gallery ventilation mode or to completely adopt jet-flow gallery ventilation.
Background: Conbercept, as a novel vascular endothelial growth factor (VEGF) inhibitor, was approved for the treatment of neovascular age-related macular degeneration (nAMD) in China. Objective: This ...study aimed to compare the efficacy and safety between conbercept and ranibizumab in patients with nAMD. Methods: Several databases (PubMed, Web of Science, China National Knowledge Infrastructure, and WANFANG) were searched for the results of studies describing conbercept and ranibizumab for the treatment of nAMD. Sixteen randomized controlled trials including 1,224 eyes met our search criteria and were assessed. Results: Conbercept and ranibizumab had comparable effects on improving visual acuity at 3 months (standardized mean difference SMD: −0.19; 95% confidence interval CI: −0.46 to 0.08; p = 0.17) and 6–12 months (SMD: −0.01; 95% CI: −0.20 to 0.18; p = 0.90). At 3 months and 6–12 months, the differences in the change of central macular thickness in conbercept and ranibizumab groups were 1.06 μm (95% CI: −3.52 to 5.64; p = 0.65) and −0.12 μm (95% CI: −9.26 to 9.02; p = 0.98). In the short term, there was no significant difference between the 2 groups with respect to ocular adverse events (odds ratio OR: 0.86; 95% CI: 0.46–1.61; p = 0.63). No significant differences were observed in the recovery rate of choroidal neovascularization leakage between conbercept and ranibizumab at both 3 months (OR: 1.49; 95% CI: 0.83–2.68; p = 0.18) and 6–12 months (OR: 0.66; 95% CI: 0.18–2.43; p = 0.53). There were significant differences between conbercept and ranibizumab in terms of decreasing intraocular pressure (weighted mean difference WMD: −1.74; 95% CI: −2.28 to −1.20; p < 0.00001), the plasma VEGF level (WMD: −21.49; 95% CI: −26.28 to −16.70; p < 0.00001), and the C-reactive protein level (WMD: −1.16; 95% CI: −1.45 to −0.87; p < 0.00001) in the short term. Conclusion: Conbercept was similar to ranibizumab in terms of efficacy and safety for the treatment of nAMD in China. Further studies with longer term observation are needed to support this conclusion.
To compare Barrett TK Universal II and Barrett Universal II TCRP calculations in the power calculations for 3 presbyopia-correcting intraocular lenses (PC-IOL).
This observational study involved 64 ...eyes from 64 patients who prepared to undergo extraction of crystalline lenses combined with PC-IOL (Symfony ZXR00, PanOptix TFNT00, or AT LISA tri 839MP) implantation. All eyes underwent ocular biometric measurements with IOLMaster 700 and Pentacam HR, and the interdevice agreement of measurements including total keratometry (TK, IOLMaster 700) and total corneal refractive power (TCRP, Pentacam HR) was evaluated. IOL power calculations were performed using TK-based Barrett TK Universal II and TCRP-based Barrett Universal II calculations, respectively.
Paired
-tests showed that the differences in white-to-white diameter, central corneal thickness, anterior chamber depth, and mean TK between IOLMaster 700 and Pentacam HR were slight but significant (all P<0.05), and the differences in recommended IOL power for emmetropia between two Barrett calculations were also significant in 3 PC-IOLs (all P<0.05). The ROC curve showed that the AUC was 0.917 (95% CI, 0.820-0.971) for the absolute value of the difference between TK and TCRP in discriminating the difference of ≥ ±0.5 D in predicted IOL power with best cutoff values of 0.4 D.
The novel Barrett TK Universal II formula built in IOLMaster 700 is comparable to TCRP-based Barrett Universal II calculation for IOL power calculation of PC-IOLs, and the convenience of using the Barrett TK Universal II formula should be founded on measurement consistency between devices.
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