Role of hsa_circ_0007482 in pterygium development: insights into proliferation, apoptosis, and clinical correlations

AIM:To investigate the impact of hsa_circ_0007482 on the proliferation and apoptosis of human pterygium fibroblasts(HPFs)and its correlation with the severity grades of pterygium.METHODS:Pterygium and normal conjunctival tissues were collected from the superior area of the same patient’s eye(n=33).The correlation between pterygium severity and hsa_circ_0007482 expression using quantitative reversetranscription polymerase chain reaction(RT-qPCR)were analyzed.Three distinct siRNA sequences targeting hsa_circ_0007482,along with a negative control sequence,were transfected into HPFs.Cell proliferation was assessed using the cell counting kit-8.Expression levels of Ki67,proliferating cell nuclear antigen(PCNA),Cyclin D1,Bax,B-cell lymphoma-2(Bcl-2),and Caspase-3 were measured via RT-qPCR.Immunofluorescence staining was employed to detect Ki67 and vimentin expressions.Apoptosis was evaluated using flow cytometry.RESULTS:Hsa_circ_0007482 expression was significantly higher in pterygium tissues compared to normal conjunctival tissues(P<0.001).Positive correlations were observed between hsa_circ_0007482 expression and pterygium severity,thickness,and vascular density.Knockdown of hsa_circ_0007482 inhibited cell proliferation,reducing the mRNA expression of Ki67,PCNA,and Cyclin D1 in HPFs.Hsa_circ_0007482 knockdown induced apoptosis,increasing mRNA expression levels of Bax and Caspase-3,while decreasing Bcl-2 expression in HPFs.Additionally,hsa_circ_0007482 knockdown attenuated vimentin expression in HPFs.CONCLUSION:The downregulation of hsa_circ_0007482 effectively hampers cell proliferation and triggers apoptosis in HPFs.There are discernible positive correlations detected between the expression of hsa_circ_0007482 and the severity of pterygium.

Probabilistic outlier detection for sparse multivariate geotechnical site investigation data using Bayesian learning

Various uncertainties arising during acquisition process of geoscience data may result in anomalous data instances(i.e.,outliers)that do not conform with the expected pattern of regular data instances.With sparse multivariate data obtained from geotechnical site investigation,it is impossible to identify outliers with certainty due to the distortion of statistics of geotechnical parameters caused by outliers and their associated statistical uncertainty resulted from data sparsity.This paper develops a probabilistic outlier detection method for sparse multivariate data obtained from geotechnical site investigation.The proposed approach quantifies the outlying probability of each data instance based on Mahalanobis distance and determines outliers as those data instances with outlying probabilities greater than 0.5.It tackles the distortion issue of statistics estimated from the dataset with outliers by a re-sampling technique and accounts,rationally,for the statistical uncertainty by Bayesian machine learning.Moreover,the proposed approach also suggests an exclusive method to determine outlying components of each outlier.The proposed approach is illustrated and verified using simulated and real-life dataset.It showed that the proposed approach properly identifies outliers among sparse multivariate data and their corresponding outlying components in a probabilistic manner.It can significantly reduce the masking effect(i.e.,missing some actual outliers due to the distortion of statistics by the outliers and statistical uncertainty).It also found that outliers among sparse multivariate data instances affect significantly the construction of multivariate distribution of geotechnical parameters for uncertainty quantification.This emphasizes the necessity of data cleaning process(e.g.,outlier detection)for uncertainty quantification based on geoscience data.

Influence of deformation zone length on bending radius of SS304 tubes with small diameters manufactured via free bending-based active motion

In three and six-axis free-bending equipment,the deformation zone length(A)is a fixed mechanical structure parameter modified when the relevant structure is redesigned and manufactured.In this study,a six degree of freedom(6-DOF)parallel mechanism was used as the control mechanism of the bending die,and a new method of changing the deformation zone length(A)was proposed.Firstly,an idealized geometric model of free bending-based active motion was established.Then,the influence of the deformation zone length(A)on the bending moment and the bending radius of the tube was analyzed.In addition,the finite element simulation and a kinematic model of free bending-based active motion controlled by the 6-DOF parallel mechanism were established,and bending processes of the SS304 tube with different deformation zone lengths were investigated.Afterwards,the impact of the deformation zone length(A)on the bending radius,bending moment,wall thickness,and motion of the parallel mechanism were analyzed.Finally,experiments were carried out on the free-bending equipment based on the 6-DOF parallel mechanism.Experiments verified the rules in the theoretical analysis,finite element simulation,and kinematic simulation.

Regulation of P450 TleB catalytic flow for the synthesis of sulfur-containing indole alkaloids by substrate structure-directed strategy and protein engineering

Indole alkaloids have attracted considerable attention from synthetic chemists and biochemists for their structural diversity and important biological activities.Compared with traditional organic synthesis methods,the strategy of using cytochrome P450s'extraordinary abilities to selectively activate carbon-hydrogen bonds to assist in the synthesis of various indole alkaloids has the characteristics of short synthetic route,mild conditions and high atomic economy.Here,we utilized P450 monooxygenases HinD and TleB to synthesize a novel 6/5/8 tricyclic product from(S)-N-((S)-1-(4-fluoro-1H-indol-3-yl)-3-hydroxypropan-2-yl)-2-mercapto-3-methylbutanamide through the substrate structure-directed strategy.TleB was more effective in catalyzing C–S coupling,and was used to synthesize a series of 6/5/8 tricyclic indololactam derivatives to provide drug candidates.Interestingly,the S–S coupling product was observed in HinD catalysis,which was a minor product in the wild-type TleB catalysis.With the help of protein engineering,we accurately regulated the catalytic flow and reversed the selectivity of TleB to obtain the S–S coupling product.At the same time,the reaction mechanism was reasonably speculated by means of site blocking and protein-substrate complex analysis.