Lutein delays photoreceptor degeneration in a mouse model of retinitis pigmentosa

Retinitis pigmentosa is a retinal disease characterized by photoreceptor degeneration. There is currently no effective treatment for retinitis pigmentosa. Although a mixture of lutein and other antioxidant agents has shown promising effects in protecting the retina from degeneration, the role of lutein alone remains unclear. In this study, we administered intragastric lutein to Pde6b^rd10 model mice, which display degeneration of retinal photoreceptors, on postnatal days 17 (P17) to P25, when rod apoptosis reaches peak. Lutein at the optimal protective dose of 200 mg/kg promoted the survival of photoreceptors compared with vehicle control. Lutein increased rhodopsin expression in rod cells and opsin expression in cone cells, in line with an increased survival rate of photoreceptors. Functionally, lutein improved visual behavior, visual acuity, and retinal electroretinogram responses in Pde6b^rd10 mice. Mechanistically, lutein reduced the expression of glial fibrillary acidic protein in Müller glial cells. The results of this study confirm the ability of lutein to postpone photoreceptor degeneration by reducing reactive gliosis of Müller cells in the retina and exerting anti-inflammatory effects. This study was approved by the Laboratory Animal Ethics Committee of Jinan University (approval No. LACUC-20181217-02) on December 17, 2018.

Current Application of Digital Diagnosing Systems for Retinopathy of Prematurity

BACKGROUND AND OBJECTIVE

Retinopathy of prematurity (ROP), a proliferative vascular eye disease, is one of the leading causes of blindness in childhood and prevails in premature infants with low-birth-weight. The recent progress in digital image analysis offers novel strategies for ROP diagnosis. This paper provides a comprehensive review on the development of digital diagnosing systems for ROP to software researchers. It may also be adopted as a guide to ophthalmologists for selecting the most suitable diagnostic software in the clinical setting, particularly for the remote ophthalmic support.

METHODS

We review the latest literatures concerning the application of digital diagnosing systems for ROP. The diagnosing systems are analyzed and categorized. Articles published between 1998 and 2020 were screened with the two searching engines Pubmed and Google Scholar.

RESULTS

Telemedicine is a method of remote image interpretation that can provide medical service to remote regions, and yet requires training to local operators. On the basis of image collection in telemedicine, computer-based image analytical systems for ROP were later developed. So far, the aforementioned systems have been mainly developed by virtue of classic machine learning, deep learning (DL) and multiple machine learning. During the past two decades, various computer-aided systems for ROP based on classic machine learning (e.g. RISA, ROPtool, CAIER) became available and have achieved satisfactory performance. Further, automated systems for ROP diagnosis based on DL are developed for clinical applications and exhibit high accuracy. Moreover, multiple instance learning is another method to establish an automated system for ROP detection besides DL, which, however, warrants further investigation in future.

CONCLUSION

At present, the incorporation of computer-based image analysis with telemedicine potentially enables the detection, supervision and in-time treatment of ROP for the preterm babies.

The function of microRNA-34a in osteoarthritis

AIM

To discuss the effects and mechanism of microRNA-34a in cell apoptosis induced by osteoarthritis.

METHODS

Collection of the normal and osteoarthritis synovial tissues and measurements of the miRNA-34a and TGIF2 gene expression. In the cell experiment, the cells were divided into Control, Blank and miRNA inhibitor group. The cell proliferation and apoptosis of the different groups were measured by MTT and flow cytometry and the TGIF2 protein expression in the different groups was evaluated by WB assay. The correlation between TGIF2 and miRNA-34a was analyzed by Double luciferase experiment.

RESULTS

Compared with normal synovial tissues, the miRNA-34a gene expression was significantly up-regulated and TGIF2 gene expression was significantly suppressed in osteoarthritis synovial tissues (p < 0.001, respectively). The cell proliferation was significantly depressed and the cell apoptosis rate was significantly increased in miRNA inhibitor group compared with the Control group (p < 0.001, respectively). Using the WB assay it was shown that the TGIF2 protein expression of miRNA inhibitor group was significantly suppressed compared with that of Control group (p < 0.01). By Double luciferase assay, TGIF2 gene was one target gene of miRNA-34a.

CONCLUSION

miRNA-34a could induce osteoarthritis synovial cell apoptosis via regulation of TGIF2 in vitro (Fig. 6, Ref. 29).

miRNA-31 over-expression improve synovial cells apoptosis induced by RA

OBJECTIVE

The aim of this study was to evaluate the effects and mechanism of miRNA-31 in synovial cells apoptosis induced by RA.

METHODS

The miRNA-31 gene expressions were extracted from synovial tissues of normal and RA patients by RT-PCR and H et E staining. The synovial cells of RA patients were isolated and randomly divided into Control, Blank and miRNA groups. The cell apoptosis of difference groups were measured by flow cytometry; the TNF-α and IL-1β concentrations of difference groups were measured by Elisa assay; TLR4 and NF-κB proteins expressions were measured by WB assay and the correlation between TLR4 and miRNA-31 were evaluated by double luciferase target experiment.

RESULTS

The miRNA-31 gene expression was significantly suppressed in RA tissues (p<0.001); Compared with control group, the cell apoptosis rate of miRNA group was significantly suppressed (p<0.001); TNF-α and IL-1β concentrations were significantly down-regulation in culture fluid (p<0.001, respectively) and TLR4 and NF-κB proteins expressions were significantly depressed (p<0.001, respectively) in miRNA group. By double luciferase target experiment, the TLR4 was a target gene of miRNA-31.

CONCLUSION

miRNA-31 is a key role in synovial cells apoptosis induced by RA (Fig. 7, Ref. 23).

Clinical use of homograft stored by vitrification

Using 20% DMSO and 6% propylene glycol in Kreb' Ringer phosphate solution as cryopotective agent for homograft vitrification storage, the viability of stored homograft (79.2%) was higher than that of slow cooling storage (59.7%). About 540000 cm2 of vitrified homograft were used to cover the wounds after excision of burn eschar in 135 patients with major burns. The take-rate was over 94%. The cryopreservation of skin by vitrification can improve the viability and quality of skin and save time and cost.

Gas chromatographic determination of mexiletine in human plasma with flame ionization detection after reaction with carbon disulphide

A gas chromatographic method for the determination of mexiletine in human plasma is described. Mexiletine was simultaneously extracted and derivatized with carbon disulphide for separation and quantitation on a glass column (1.5 m x 3 mm i.d.) packed with 1.5% OV-1 coated on 80-100 mesh Shimalite W (201D). The method required only 0.5 mL of plasma and could detect as little as 10 ng of mexiletine. It has been applied to the study of the pharmacokinetics of mexiletine in healthy volunteers.