Retrospective analysis of cataract surgery outcomes in China from 2009 to 2018: from a national registry system data.

OBJECTIVE: To evaluate patients' benefits after cataract surgery and to form recommendations for Chinese national health policy decision makers and administration departments based on the quality of cataract treatments. METHOD: An observational study based on real-world data source from the National Cataract Recovery Surgery Information Registration and Reporting System. RESULTS: A total of 14 157 463 original records were reported from 1 July 2009 to 31 December 2018. The factors that influenced the 3-day postsurgical best-corrected visual acuity (BCVA), the primary outcome, were analysed by logistic regression analysis. We found that a history of hypertension (OR=0.916) or diabetes (OR=0.912), presurgical pupil abnormality (OR=0.571) and high intraocular pressure (OR=0.578) were harmful to the postsurgical BCVA improvement (BCVA ≥6/20), while male sex (OR=1.113), better presurgical BCVA level (OR=5.996 for ≥6/12-<6/7.5 and OR=2.610 for >6/60-<6/12 taken ≤6/60 as reference), age-related cataract (OR=1.825) and intraocular lens implantation (OR=1.886) were statistically beneficial to the postsurgical BCVA improvement. Compared with extracapsular cataract extraction (ECCE) with large incision, the ECCE with small incision (OR value=1.810) and the phacoemulsification (OR=1.420) significantly improved the benefit probability. CONCLUSION: ECCE with small incision has comparable effects on postsurgical BCVA improvement of phacoemulsification. Therefore, ECCE could be an alternative cataract surgical treatment in economically underdeveloped areas in China, provided the surgeons are adequately trained.

Erratum to: TfR1 Extensively Regulates the Expression of Genes Associated with Ion Transport and Immunity.

It is hereby certified that there is no shared co-first authorship in this paper. Dr. Nan HUANG is the only first author of this article.

TfR1 Extensively Regulates the Expression of Genes Associated with Ion Transport and Immunity.

Transferrin receptor 1 (TfR1), encoded by the TFRC gene, is the gatekeeper of cellular iron uptake for cells. A variety of molecular mechanisms are at work to tightly regulate TfR1 expression, and abnormal TfR1 expression has been associated with various diseases. In the current study, to determine the regulation pattern of TfR1, we cloned and overexpressed the human TFRC gene in HeLa cells. RNA-sequencing (RNA-seq) was used to analyze the global transcript levels in overexpressed (OE) and normal control (NC) samples. A total of 1669 differentially expressed genes (DEGs) were identified between OE and NC. Gene ontology (GO) analysis was carried out to explore the functions of the DEGs. It was found that multiple DEGs were associated with ion transport and immunity. Moreover, the regulatory network was constructed on basis of DEGs associated with ion transport and immunity, highlighting that TFRC was the node gene of the network. These results together suggested that precisely controlled TfR1 expression might be not only essential for iron homeostasis, but also globally important for cell physiology, including ion transport and immunity.

A comparative analysis on human resources among the specialized ophthalmic medical institutions in China.

BACKGROUND: This study compares perspectives on specialized ophthalmic medical institutions, identifies the gaps in property and geographic offerings, and explores the ways that ophthalmic medical institutions can better allocate resources. The results of this research will increase patient's access to equitable and high-quality ophthalmic care in China. METHODS: The data for this research was gathered from the Survey of China National Eye Care Capacity and Resource for the year 2015. The paper specified the number, professional level of expertise, and educational background of ophthalmic health personnel. The authors of the paper analyzed and compared the differences in ophthalmic care in public vs. private and urban vs. rural regions in China. Descriptive statistics were used. RESULTS: Of the 395 specialized ophthalmic hospitals surveyed, 332 were private medical institutions (84%), and 63 were public (16%). Of the 26 607 ophthalmic personnel surveyed, working in specialized ophthalmic hospitals, 17 561 were in private hospitals (66%) and 9 046 were in public ones (34%). Furthermore, 22 578 of those personnel worked in urban ophthalmic institutions (85%) and 4 029 worked in rural ones (15%). As for regional differences, 14 090 personnel were located in eastern China (53%), 8 828 in central regions (33%), and 3 689 in the western regions (14%). CONCLUSIONS: Public ophthalmic medical institutions still face challenges in providing equitable and widespread care. The availability of well-staffed health centers varies significantly by region. These variations impact resource allocation and directly lead to inequalities and inaccessibility of health services in certain regions of China.

Comparative study on seasonal hair follicle cycling by analysis of the transcriptomes from cashmere and milk goats.

Guard hair and cashmere undercoat are developed from primary and secondary hair follicle, respectively. Little is known about the gene expression differences between primary and secondary hair follicle cycling. In this study, we obtained RNA-seq data from cashmere and milk goats grown at four different seasons. We studied the differentially expressed genes (DEGs) during the yearly hair follicle cycling, and between cashmere and milk goats. WNT, NOTCH, MAPK, BMP, TGFß and Hedgehog signaling pathways were involved in hair follicle cycling in both cashmere and milk goat. However, Milk goat DEGs between different months were significantly more than cashmere goat DEGs, with the largest difference being identified in December. Some expression dynamics were confirmed by quantitative PCR and western blot, and immunohistochemistry. This study offers new information sources related to hair follicle cycling in milk and cashmere goats, which could be applicable to improve the wool production and quality.

Inequity in Access: Cataract Surgery Throughput of Chinese Ophthalmologists from the China National Eye Care Capacity and Resource Survey.

Purpose: To investigate the distribution of cataract surgery performed by ophthalmologists in China.Methods: A cross-sectional study was designed to investigate nationwide ophthalmological resources and capacity for cataract surgery in China⁠-The 2014 China National Eye Care Capacity and Resource Survey. Data analyzed in this report included regional distribution, urban-rural comparison, levels and types of medical institutions, and cataract surgery types and volume per surgeon. In China, only ophthalmologists at or above the level of attending are eligible to perform cataract surgery independently, so the ability of cataract surgery for ophthalmologists at or above the level of attending is analyzed in the current study. Descriptive statistics were used.Results: 36,333 ophthalmologists were included in this survey, which is an average of 1.33 ophthalmologists to every 50,000 population. Of the surgeons in this survey, 23,412 (50.22%) were attending or more senior ophthalmologists and were mainly distributed in eastern urban areas. Annual average cataract surgeries per ophthalmologist in China were 259 in 2017, less than 300 cases.Conclusion: The average number of ophthalmologists per population in China has achieved the goal of WHO's Vision 2020; however, these surgeons are concentrated in urban areas. Further, the ability of cataract surgery among ophthalmologists is unbalanced. The annual average cataract surgeries performed by ophthalmologists are insufficient, which is an important factor resulting in the current situation in China that ophthalmic service capacity has not met the requirements for eliminating cataract blindness.

Correction: Assessment of trachoma in suspected endemic areas within 16 provinces in mainland China.

[This corrects the article DOI: 10.1371/journal.pntd.0007130.].

The susceptibility of sea-island cotton recombinant inbred lines to Fusarium oxysporum f. sp. vasinfectum infection is characterized by altered expression of long noncoding RNAs.

Disease resistance is one of the most complicated yet important plant traits. The potential functions of long noncoding RNAs (lncRNAs) in response to pathogenic fungi remain unclear. In this study, we sequenced the transcriptomes of four different sea-island cotton (Gossypium barbadense) recombinant inbred lines (RILs) with susceptible, highly susceptible, highly resistant, or super highly resistant phenotypes and compared their responses to Fusarium oxysporum f. sp. vasinfectum (Fov) infection with those of their susceptible and resistant parents. Infection-induced protein coding genes were highly enriched in similar disease resistance-related pathways regardless of fungal susceptibility. In contrast, we found that the expression of a large number of Fov infection-induced lncRNAs was positively correlated with plant susceptibility. Bioinformatics analysis of potential target mRNAs of lncRNAs with both trans-acting and cis-acting mechanisms showed that mRNAs co-expressed or co-located with Fov-regulated lncRNAs were highly enriched in disease resistance-related pathways, including glutathione metabolism, glycolysis, plant hormone signal transduction, anthocyanin biosynthesis, and butanoate metabolism. Together these results suggest that lncRNAs could play a significant role in the response to pathogenic fungal infection and the establishment of disease resistance. The transcriptional regulation of these infection-susceptible lncRNAs could be coordinated with infection-susceptible mRNAs and integrated into a regulatory network to modulate plant-pathogen interactions and disease resistance. Fov-susceptible lncRNAs represent a novel class of molecular markers for breeding of Fov-resistant cotton cultivars.

Grape seed proanthocyanidins inhibit proliferation of pancreatic cancer cells by modulating microRNA expression.

MicroRNAs (miRNAs) are small non-coding RNAs of 18-25 nucleotides that modulate gene expression at the post-transcriptional level. Grape seed proanthocyanidins (GSPs), which are biologically active components in grape seeds, have been demonstrated to exhibit anticancer effects. The current study investigated whether GSPs can regulate miRNA expression and the possible anticancer molecular mechanisms of GSPs. Pancreatic cancer (PC) cell samples, SS3, SS12 and SS24, were treated with 20 µg/ml GSPs for 3, 12 and 24 h, respectively. Control samples, SC3, SC12 and SC24, were also prepared. Using miRNA-seq, transcriptome analysis identified 24, 83 and 83 differentially expressed (DE) miRNAs in SS3 vs. SC3, SS12 vs. SC12 and SS24 vs. SC24, respectively. This indicated that treatment with GSPs could modulate the expression of miRNAs. Subsequently, 74, 598 and 1,204 target genes for the three sets of DE miRNAs were predicted. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis revealed that multiple target genes were associated with the proliferation and apoptosis of PC cells. In addition, a network was constructed of the DE miRNAs and the target genes associated with PC. The associations identified suggested that treatment with GSPs may inhibit the proliferation of PC cells through the modulation of miRNA expression.

Transcriptome analysis of pancreatic cancer cell response to treatment with grape seed proanthocyanidins.

Grape seed proanthocyanidins (GSPs) have been demonstrated to exhibit potential chemotherapeutic efficacy against various cancer types. To determine the underlying molecular mechanisms involved in GSP-induced apoptosis, the present study prepared pancreatic cancer (PC) cells samples, S3, S12 and S24, which were treated with 20 µg/ml GSPs for 3, 12 and 24 h, respectively. Control cell samples, C3, C12 and C24, were also prepared. Using RNA-sequencing, transcriptome comparisons were performed, which identified 966, 3,543 and 4,944 differentially-expressed genes (DEGs) in S3 vs. C3, S12 vs. C12 and S24 vs. C24, respectively. Gene Ontology analysis of the DEGs, revealed that treatment with GSPs is associated with disruption of the cell cycle (CC) in PC cells. Additionally, disruption of transcription, DNA replication and DNA repair were associated with GSP-treatment in PC cells. Network analysis demonstrated that the common DEGs involved in the CC, transcription, DNA replication and DNA repair were integrated, and served essential roles in the control of CC progression in cancer cells. In summary, GSPs may exhibit a potential chemotherapeutic effect on PC cell proliferation.

Assessment of trachoma in suspected endemic areas within 16 provinces in mainland China.

BACKGROUND: China used to be among the countries with a high prevalence of trachoma. At the launch of The Global Elimination of Trachoma (GET) 2020 campaign by the World Health Organization (WHO) in 1996, China was placed on the list of countries endemic for trachoma based on historical data. However, empirical observation and routinely collected eye care data were suggesting that trachoma was no longer a public health problem. To determine whether the GET 2020 goals had been met in P. R. China, we conducted a targeted assessment with national scope. METHODOLOGY/PRINCIPAL FINDING: Province assessment teams, trained in WHO Trachoma Rapid Assessment (TRA) methodology and in WHO simplified trachoma grading system, carried out assessments in 16 provinces (among them, 2 provinces conducted pilot assessment). Based on the published literature, including national and international reports, suspected trachoma-endemic areas within each province were identified. Within these areas, trachomatous inflammation- follicular (TF) assessments were carried out in at least 50 grade-one children in primary schools serving villages with the lowest socio-economic development. Trachomatous trichiasis (TT) and corneal opacity (CO) assessments were conducted among persons aged 15 and over in villages within the catchment area of the selected schools. Of 8,259 children examined in 128 primary schools in 97 suspected trachoma endemic areas, only 16 cases of conjunctivitis were graded as TF. 38 cases with TT were found among the 339,013 examined residents in villages surrounding the schools. Among these 97 suspected trachoma endemic areas in only three was the prevalence of TT more than 0.2%. CONCLUSIONS/SIGNIFICANCE: This large study suggested that trachoma was not a public health problem in 16 provinces that had been previously suspected to be endemic. These findings will facilitate planning for elimination of trachoma from PR China.

Competing RNA pairings in complex alternative splicing of a 3' variable region.

Alternative pre-mRNA splicing remarkably expands protein diversity in eukaryotes. Drosophila PGRP-LC can generate three major 3' splice isoforms that exhibit distinct innate immune recognition and defenses against various microbial infections. However, the regulatory mechanisms underlying the uniquely biased splicing pattern at the 3' variable region remain unclear. Here we show that competing RNA pairings control the unique splicing of the 3' variable region of Drosophila PGRP-LC pre-mRNA. We reveal three roles by which these RNA pairings jointly regulate the 3' variant selection through activating the proximal 3' splice site and concurrently masking the intron-proximal 5' splice site, in combination with physical competition of RNA pairing. We also reveal that competing RNA pairings regulate alternative splicing of the highly complex 3' variable regions of Drosophila CG42235 and Pip Our findings will facilitate a better understanding of the regulatory mechanisms of highly complex alternative splicing as well as highly variable 3' processing.

Transcriptome analysis of sheep oral mucosa response to Orf virus infection.

Contagious ecthyma is a highly contagious disease with worldwide distribution, which is caused by the Orf virus (ORFV) belonging to the Parapoxvirus. To study the alteration of host gene expression in response to ORFV infection at the transcriptional level, several young small-tailed Han sheep were inoculated with ORFV, and their oral mucosa tissue samples (T0, T3, T7 and T15) were collected on day 0, 3, 7 and 15 after ORFV infection respectively. RNA-seq transcriptome comparisons were performed, showing that 1928, 3219 and 2646 differentially expressed genes (DEGs) were identified among T3 vs. T0, T7 vs. T0, and T15 vs. T0 respectively. Gene Ontology (GO) analyses of the DEGs from these comparisons, revealed that ORFV might provoke vigorous immune response of the host cells during the early stage of infection. Moreover, GO and network analysis showed that positive and negative regulative mechanisms of apoptosis were integrated in the host cells through up or down-regulating the expression level of DEGs involved in apoptotic pathways, in order to reach a homeostasis of oral mucosa tissues during the exposure to ORFV infection. In conclusion, our study for the first time describes the direct effects of ORFV on the global host gene expression of its host using high-throughput RNA sequencing, which provides a resource for future characterizing the interaction mechanism between the mammalian host and ORFV.

Role and convergent evolution of competing RNA secondary structures in mutually exclusive splicing.

Exon or cassette duplication is an important means of expanding protein and functional diversity through mutually exclusive splicing. However, the mechanistic basis of this process in non-arthropod species remains poorly understood. Here, we demonstrate that MRP1 genes underwent tandem exon duplication in Nematoda, Platyhelminthes, Annelida, Mollusca, Arthropoda, Echinodermata, and early-diverging Chordata but not in late-diverging vertebrates. Interestingly, these events were of independent origin in different phyla, suggesting convergent evolution of alternative splicing. Furthermore, we showed that multiple sets of clade-conserved RNA pairings evolved to guide species-specific mutually exclusive splicing in Arthropoda. Importantly, we also identified a similar structural code in MRP exon clusters of the annelid, Capitella teleta, and chordate, Branchiostoma belcheri, suggesting an evolutionarily conserved competing pairing-guided mechanism in bilaterians. Taken together, these data reveal the molecular determinants and RNA pairing-guided evolution of species-specific mutually exclusive splicing spanning more than 600 million years of bilaterian evolution. These findings have a significant impact on our understanding of the evolution of and mechanism underpinning isoform diversity and complex gene structure.

[A prospective study of serum fibroblast growth factor 21 changes in nonalcoholic fatty liver patients].

OBJECTIVE: To investigate the prospective association of fibroblast growth factor 21 (FGF-21) with NAFLD development in a 5-year prospective study involving a population-based cohort comprising 352 Chinese subjects. METHODS: The clinical data of subjects were recorded, serum FGF-21 levels at baseline and follow-up were measured using an enzyme-linked immunosorbent assay,whether FGF-21 was independent predictor of NAFLD development were identified using logistic regressions. Chi-square test, non-parametric test and logistic regression analysis were used in statistical analyses. RESULTS: (1) Serum FGF-21 levels of NAFLD group was significantly higher than that of non-NAFLD group (318.34(169.64,520.77)pg/ml vs 197.22 (121.57, 318.76) pg/ml, Probability value less than 0.05). (2)At follow-up,significant increase of FGF-21 level was observed in those subjects who developed NAFLD (399.4 (253.9,754.2) pg/ml vs 318.34(169.64, 520.77)pg/ml, Probability value less than 0.05), but in non-NAFLD group, there was no significant difference of FGF-21 level between baseline and follow-up. (3) BMI, TC, HOMA-IR and FGF-21 were independent predictors of NAFLD through logistic regressions. CONCLUSION: High FGF-21 levels was independent predictor of NAFLD, it may be useful for early diagnosis and intervention of NAFLD.

Origin and evolution of a new retained intron on the vulcan gene in Drosophila melanogaster subgroup species.

Although numerous intron gains have been discovered, the mechanisms of intron creation have proven to be elusive. Previous study revealed that the vulcan gene of Drosophila melanogaster contained four exons in its coding region. In the current study, a newly created intron (Intron L) was identified on exon 2 of vulcan in D. melanogaster by comparing expression sequence tags. The RT-PCR experiment revealed that Intron L was associated with intron retention, in which two alternative transcripts of the gene differ by the inclusion or removal of an intron. It was found that Intron L was created by intronization of exonic sequence, and its donor and acceptor splice sites were created by synonymous mutation, leading to the origin of a new vulcan protein that is 22 amino acids shorter than the previously reported vulcan protein. Moreover, to track the origin of Intron L, 36 orthologous genes of species of Drosophila were cloned or annotated, and phylogenetic analysis was carried out. It indicated that the common ancestor of D. melangaster subgroup species created Intron L about 15 million years ago.

Origin and evolution of a new exon of 14-3-3ξ in bees and phylogenetic analysis.

Mutually exclusive splicing, one type of alternative splicing, involves selection of alternatively spliced exons arranged in tandem and creates protein products with substitution of one segment of the amino acid sequence for another. Previous studies revealed that exon 5 of 14-3-3ξ from Apis mellifera (western honeybee) had three mutually exclusive exons, while orthologous exon of Nasonia vitripennis (parasitic wasp) had only two, suggesting that cases of exon gain or loss might have happened during the evolution of hymenopteran species. In the current study, we annotated and analyzed the 14-3-3ξ genes from 20 hymenopteran species successfully, and the results of phylogenetic analysis revealed the presence of a new mutually exclusive exon in corbiculate bees. In addition, we found that duplication via staggered homologous recombination was responsible for the origin of the new exon.

An RNA architectural locus control region involved in Dscam mutually exclusive splicing.

The most striking example of alternative splicing in a Drosophila melanogaster gene is observed in the Down syndrome cell adhesion molecule, which can generate 38,016 different isoforms. RNA secondary structures are thought to direct the mutually exclusive splicing of Down syndrome cell adhesion molecule, but the underlying mechanisms are poorly understood. Here we describe a locus control region that can activate the exon 6 cluster and specifically allow for the selection of only one exon variant in combination with docking site selector sequence interactions. Combining comparative genomic studies of 63 species with mutational analysis reveals that intricate, tandem multi-'subunit' RNA structures within the locus control region activate species-appropriate alternative variants. Importantly, strengthening the weak splice sites of the target exon can remove the locus control region dependence. Our findings not only provide a locus control region-dependent mechanism for mutually exclusive splicing, but also suggest a model for the evolution of increased complexity in a long-range RNA molecular machine.

Conservation and regulation of alternative splicing by dynamic inter- and intra-intron base pairings in Lepidoptera 14-3-3ξ pre-mRNAs.

Alternative splicing of pre-mRNAs greatly contributes to diversity in products generated from a single gene. However, the underlying regulatory mechanisms are poorly understood. In the present study, we describe evolutionarily conserved intra-intronic and inter-intronic RNA secondary structures. Mutation experiments revealed that intra-intronic RNA secondary structure causes steric hindrance to enforce mutual splicing exclusivity, while inter-intronic RNA pairing largely functions through a looped-out mechanism. Moreover, mutually exclusive splicing may be regulated by RNA pairing competition between intra- and inter-introns. Importantly, the resulting dynamic RNA architecture largely controls mutually exclusive splicing, although cis-acting regulatory sequences may fine-tune this process. Our results emphasize the importance of dynamic RNA architecture in alternative splicing.

Convergent intron loss of MRP1 in Drosophila and mosquito species.

Previous study revealed that the MRP1 gene ortholog DMRP1/CG6214 of Drosophila melanogaster contains 12 exons in the coding region. In the current study, the genes of DMRP1/CG6214 from D. melanogaster and Drosophila virilis were compared, and the result indicated that D. virilis had an extra intron located in exon 2, implying that intron loss or gain might have occurred at this locus. To track the evolution of the extra intron (Intron Z), orthologous nucleotide sequences of 37 arthropod species were cloned or annotated. Based on phylogenetic analysis, we found that Intron Z should present in the common ancestor of arthropod species, more than 420 Ma. In addition, we found that Sophophora subgenus species and mosquito (Culex pipiens) lost Intron Z independently, showing evolutionary convergence.