Research advances in the mechanism of subthreshold micropulse laser in diabetic macular edema / 中华眼底病杂志

In recent years, the subthreshold micropulse laser is a kind of laser mode which is characterized by long intermittence. It achieves effective therapeutic effect while minimizes the damage to tissues. At present, it has been used to treat diabetic macular edema. Early studies suggested that the laser selectively acts on retinal pigment epithelial cells to reduce macular edema by regulating the expression of inflammatory biomarkers, growth factors, heat shock proteins and other substances. In recent years, with the development of research, more and more emphasis has been placed on the role of retinal glial cells. Müller cells are also considered as one of the target cells affected by micropulse laser, but there is no evidence of direct or indirect effects of micropulse laser on Müller cells. In the near future, it is expected that we will have more clinical evidence to confirm the target cells of the micropulse laser, which may be further confirmed by in vitro experiments through Müller cells or Müller cells co-cultured with retina pigment epithelium cells, so as to make a more detailed statement on the mechanism of it.

Bibliometric analysis of proliferative vitreoretinopathy based on Web of Science database / 中华实验眼科杂志

Objective:To study the distribution of the literature and the trend of international research of proliferative vitreoretinopathy (PVR) in 10 years from 2009 to 2018.Methods:Using Web of Science database of the American Institute of Scientific Information as the data source to collect literature on proliferative vitreoretinopathy published from 2009 to 2018 and a statistical analysis on the distribution of the publication time, nation and funding agency was made to figure out the institution, periodical, author with highest citations respectively among the collected literature.Meanwhile, the bibliometric analysis software Citespace and VOSviewer were employed to carry out the distribution analysis and cluster analysis of keywords as well as the co-citation cluster analysis.Results:A total of 905 articles related to PVR were included, mainly in English, most of which were written by American authors, and the number of literature published by Chinese authors was ranked the second.Among all the article funding institutions, the National Natural Science Foundation of China ranked NO.1 with the most funded articles.Citations increased year by year since 2009 and increased obviously since 2013.The journal with the highest citations was Investigative Ophthalmology & Visual Science, and the research institution with the highest citations was Harvard University.The statistical analysis of the citation quantity also showed that the top five authors with the highest citations were all from Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School.The results of cluster analysis showed that there were 41 high-frequency subject terms, and they were mainly grouped in 4 categories, which were etiology, risk factors, molecular mechanism, treatment and management of PVR.Keywords network visualization and overlay visualization both showed that etiology and risk factors were the focus of current research, while epithelial mesenchymal transition, transforming growth factor-β and fibrosis were new research fields in recent years.The results of citation cluster analysis showed there were 12 co-citation clusters. Conclusions:The literature of PVR shows an upward trend, and the researches focus on the molecular mechanism, prevention, and neuroprotection of PVR, which may be the future PVR research direction.

DNA Vaccines Encoding Toxoplasma gondii Cathepsin C 1 Induce Protection against Toxoplasmosis in Mice

Toxoplasma gondii cathepsin C proteases (TgCPC1, 2, and 3) are important for the growth and survival of T. gondii. In the present study, B-cell and T-cell epitopes of TgCPC1 were predicted using DNAstar and the Immune Epitope Database. A TgCPC1 DNA vaccine was constructed, and its ability to induce protective immune responses against toxoplasmosis in BALB/c mice was evaluated in the presence or absence of the adjuvant α-GalCer. As results, TgCPC1 DNA vaccine with or without adjuvant α-GalCer showed higher levels of IgG and IgG2a in the serum, as well as IL-2 and IFN-γ in the spleen compared to controls (PBS, pEGFP-C1, and α-Galcer). Upon challenge infection with tachyzoites of T. gondii (RH), pCPC1/α-Galcer immunized mice showed the longest survival among all the groups. Mice vaccinated with DNA vaccine without adjuvant (pCPC1) showed better protective immunity compared to other controls (PBS, pEGFP-C1, and α-Galcer). These results indicate that a DNA vaccine encoding TgCPC1 is a potential vaccine candidate against toxoplasmosis.

Sequence Variation in Superoxide Dismutase Gene of Toxoplasma gondii among Various Isolates from Different Hosts and Geographical Regions

Toxoplasma gondii, an obligate intracellular protozoan parasite of the phylum Apicomplexa, can infect all warm-blooded vertebrates, including humans, livestock, and marine mammals. The aim of this study was to investigate whether superoxide dismutase (SOD) of T. gondii can be used as a new marker for genetic study or a potential vaccine candidate. The partial genome region of the SOD gene was amplified and sequenced from 10 different T. gondii isolates from different parts of the world, and all the sequences were examined by PCR-RFLP, sequence analysis, and phylogenetic reconstruction. The results showed that partial SOD gene sequences ranged from 1,702 bp to 1,712 bp and A + T contents varied from 50.1% to 51.1% among all examined isolates. Sequence alignment analysis identified total 43 variable nucleotide positions, and these results showed that 97.5% sequence similarity of SOD gene among all examined isolates. Phylogenetic analysis revealed that these SOD sequences were not an effective molecular marker for differential identification of T. gondii strains. The research demonstrated existence of low sequence variation in the SOD gene among T. gondii strains of different genotypes from different hosts and geographical regions.

Promoter hypermethylation of the RUNX3 gene in colorectal carcinogenesis and its prognostic significance / 中华普通外科杂志

ObjectiveToinvestigateRUNX3genepromoter methylationincolorectal carcinogenesis and its prognostic significance. MethodsThe protein expression of RUNX3 was detected by immunohistochemistry and the methylation status of the RUNX3 was determined by methylation-specific PCR (MSP) in colorectal normal mucosa and cancer tissue from 65 patients,and adenoma from 28 patients.5-year overall survival rate was analysed according to RUNX3 methylation status from cancer patients.Kruskal-Wallis rank sum test,x2 or Fisher's exact test,Log-rank test and multivariable Cox regression analysis were used for statistical analysis.ResultsThe protein expression of RUNX3 gene in adenoma and cancer was 85％ (24/28) and 52％ (34/65),significantly lower than that in normal mucosa 94％ (61/65)( x2 =4.328,P =0.037 ; x2 =16.675,P =0.000),the difference between adenoma and cancer tissue was no statistic significance (x2 =3.266,P =0.071 ).No case showed RUNX3 methylation in normal mucosa,methylation rates in adenoma and cancer tissue were 21％ (6/28) and 35％ (23/65),significantly higher than in normal mucosa (P =0.000 ),but there was no statistic significance between adenoma and cancer tissue (x2 =1.766,P =0.183).The protein expression rate with RUNX3 methylation was 67％ (4/6) in adenoma,unmethylation 91％ (20/22) (P =0.191 ).The protein expression rate with RUNX3 methylation was 26％ (6/23) in cancer,unmethylation was 88％ (28/32).The presence of RUNX3 methylation was related to loss of protein ( x2 =9.810,P =0.002 ).5-year total survival rate with methylation in cancer was significantly lower with unmethylation ( x2 =5.87,P =0.016 ).Multivariate analysis showed RUNX3 methylayion wasanindependentprognosticfactoramongthefactorsanalyzed(P=0.033 ).ConclusionsRUNX3 methylation is important genetic event in colorectal carcinogenesis,possibly related to protein downregulation,and an independent prognostic factor for colorectal carcinoma.