Efficacy of the WINROP algorithm for retinopathy of prematurity screening in Southern China.

AIM: To evaluate the predicting efficacy of severe retinopathy of prematurity (ROP) by the WINROP algorithm (http://winrop.com) in Southern China. METHODS: All preterm infants with the gestational age (GA) less than 32wk were included. Their ROP screening results and serial postnatal body weight were analysed retrospectively. Weekly body weight was entered into and measured by the WINROP system. The outcomes were analysed, and the sensitivity, specificity, positive predictive value and negative predictive value (NPV) were calculated. RESULTS: Totally 432 infants with a median GA of 30.0 (24.0-31.9)wk, and a median birth weight (BW) of 1360 (540-2700) g were included. Among these 432 infants, 50 were diagnosed as type 1 ROP but only 28 were identified by the WINROP algorithm. The sensitivity was 56% (28/50) and the NPV was 92% (252/274). However, for infants with BW <1000 g or GA <28wk, the sensitivity was 93.8% (15/16) and 93.3% (14/15), respectively. Meanwhile, with several postnatal complications added as additional risk factors, the sensitivity was increased to 96% (48/50). CONCLUSION: The sensitivity of the WINROP algorithm from the Southern Chinese cohort is not as high as that reported in developed countries. This algorithm is effective for detecting severe ROP from extremely small or preterm infants. Modification of the algorithm with additional risk factors could improve the predictive value for infants with a GA>28wk in China.

The Risk Factors of Acquiring Severe Hand, Foot, and Mouth Disease: A Meta-Analysis.

OBJECTIVES: The incidence of severe hand, foot, and mouth disease (HFMD) is not low, especially in mainland China in almost every year recently. In this study, we conducted a meta-analysis to generate large-scale evidence on the risk factors of severe HFMD to provide suggestions on prevention and controlling. METHODS: PubMed, Web of Science, Embase, Cochrane Library, China National Knowledge Infrastructure (CNKI), and Wanfang (Chinese) were searched to identify relevant articles. All analyses were performed using Stata 14.0. RESULTS: We conducted a meta-analysis of 11 separate studies. Fever (odds ratio (OR) 7.396, 95% confidence interval (CI) 3.565-15.342), fever for more than 3 days (OR 5.773, 95% CI 4.199-7.939), vomiting (OR 6.023, 95% CI 2.598-13.963), limb trembling (OR 42.348, 95% CI 11.765-152.437), dyspnea (OR 12.869, 95% CI 1.948-85.017), contact with HFMD children (OR 5.326, 95% CI 1.263-22.466), rashes on the hips (OR 1.650, 95% CI 1.303-2.090), pathologic reflexes (OR 3057.064, 95% CI 494.409-19000), Lethargy (OR 31.791, 95% CI 3.369-300.020), convulsions (OR 23.652, 95% CI 1.973-283.592), and EV71 infection (OR 9.056, 95% CI 4.102-19.996) were significantly related to the risk of severe HFMD. We did not find an association between female sex (OR 0.918, 95% CI 0.738-1.142), scatter-lived children (OR 1.347, 95% CI 0.245-7.397), floating population (OR 0.847, 95% CI 0.202-3.549), rash on the hands (OR 0.740, 95% CI 0.292-1.874), rash on the foot (OR 0.905, 95% CI 0.645-1.272), the level of the clinic visited first (below the country level) (OR 5.276, 95% CI 0.781-35.630), breast feeding (OR 0.523, 95% CI 0.167-1.643), and the risk of severe HFMD. CONCLUSIONS: Fever, fever for more than 3 days, vomiting, limb trembling, dyspnea, contact with HFMD children, rashes on the hips, pathologic reflexes, lethargy, convulsions, and EV71 infection are risk factors for severe HFMD.

[Effects of crude toxin from Alternaria alternata on the growth and physiological metabolism of chrysanthemum 'Jinba' seedlings]. / é“¾æ ¼å­¢èŒç²—æ¯’ç´ å¯¹èŠèŠ±'神马'幼苗生长及生理代谢的影响.

The chrysanthemum black spot caused by Alternaria alternata significantly reduced the quality and yield of chrysanthemum. The crude toxin secreted by A. alternata in the metabolic process have elopathic effects on plants, which is the main pathogenic factor for the occurrence of chrysanthemum black spot. The pathogenic fungi A. alternate was isolated from chrysanthemum black spot leaves, The effects of crude toxin on plant height, stem diameter, root length, resistant material content, membrane relative permeability, polyphenol oxidase (PPO), peroxidase (POD), phenylalanine ammonia-lyase (PAL) in different treatments of chrysanthemum 'Jinba' seedlings were investigated. The results showed that the crude toxin of A. alternata had an inhibition effect on plant height, stem diameter and root length. The toxin concentration was positively correlated with the inhibitory effect. 14 days after crude toxin treatment, plant height, stem diameter and root length were significantly inhibited, with an reduction of 28.9%, 21.4% and 23.3%, respectively. The cell membrane permeability of leaf increased with the toxin concentration. Under the same toxin concentration, the cell membrane permeability first increased and then decreased with the treatment duration. The contents of soluble protein, malondialdehyde (MDA) and proline in leaves were significantly increased after treatment with the toxin solution. The increases of PAL, POD and PPO were the most significant in 10 times A. alternatacrude toxin treatment. The pathogenicity of A. alternate crude toxin to the chrysanthemum 'Jinba' seedlings was mainly through inhibi-ting the normal growth of roots and stems, destructing the root cell membrane permeability and increasing the contents of MDA, normal soluble sugar and proline, and promoting the activities of PAL, POD, PPO in leaf tissues.

The GDP-switched GAF domain of DcpA modulates the concerted synthesis/hydrolysis of c-di-GMP in Mycobacterium smegmatis.

The second messenger c-di-GMP [bis-(3'-5')-cyclic dimeric guanosine monophosphate] plays a key role in bacterial growth, survival and pathogenesis, and thus its intracellular homeostasis should be finely maintained. Mycobacterium smegmatis encodes a GAF (mammalian cGMP-regulated phosphodiesterases, Anabaenaadenylyl cyclases and Escherichia coli transcription activator FhlA) domain containing bifunctional enzyme DcpA (diguanylate cyclase and phosphodiesterase A) that catalyzes the synthesis and hydrolysis of c-di-GMP. Here, we found that M. smegmatis DcpA catalyzes the hydrolysis of c-di-GMP at a higher velocity, compared with synthetic activity, resulting in a sum reaction from the ultimate substrate GTP to the final product pGpG [5'-phosphoguanylyl-(3'-5')-guanosine]. Fusion with the N-terminal GAF domain enables the GGDEF (Gly-Gly-Asp-Glu-Phe) domain of DcpA to dimerize and accordingly gain synthetic activity. Screening of putative metabolites revealed that GDP is the ligand of the GAF domain. Binding of GDP to the GAF domain down-regulates synthetic activity, but up-regulates hydrolytic activity, which, in consequence, might enable a timely response to the transient accumulation of c-di-GMP at the stationary phase or under stresses. Combined with the crystal structure of the EAL (Glu-Ala-Leu) domain and the small-angle X-ray scattering data, we propose a putative regulatory model of the GAF domain finely tuned by the intracellular GTP/GDP ratio. These findings help us to better understand the concerted control of the synthesis and hydrolysis of c-di-GMP in M. smegmatis in various microenvironments.

Anticancer effect of icaritin on human lung cancer cells through inducing S phase cell cycle arrest and apoptosis.

Icaritin, a prenylflavonoid derivative from Epimedium Genus, has been shown to exhibit many pharmacological and biological activities. However, the function and the underlying mechanisms of icaritin in human non-small cell lung cancer have not been fully elucidated. The purpose of this study was to investigate the anticancer effects of icaritin on A549 cells and explore the underlying molecular mechanism. The cell viability after icaritin treatment was tested by MTT assay. The cell cycle distribution, apoptosis and reactive oxygen species (ROS) levels were analyzed by flow cytometry. The mRNA and protein expression levels of the genes involved in proliferation and apoptosis were respectively detected by RT-PCR and Western blotting. The results demonstrated that icaritin induced cell cycle arrest at S phase, and down-regulated the expression levels of S regulatory proteins such as Cyclin A and CDK2. Icaritin also induced cell apoptosis characterized by positive Hoechst 33258 staining, accumulation of the Annexin V-positive cells, increased ROS level and alteration in Bcl-2 family proteins expression. Moreover, icaritin induced sustained phosphorylation of ERK and p38 MAPK. These findings suggested that icaritin might be a new potent inhibitor by inducing S phase arrest and apoptosis in human lung carcinoma A549 cells.

Structure of pneumococcal peptidoglycan hydrolase LytB reveals insights into the bacterial cell wall remodeling and pathogenesis.

Streptococcus pneumoniae causes a series of devastating infections in humans. Previous studies have shown that the endo-ß-N-acetylglucosaminidase LytB is critical for pneumococcal cell division and nasal colonization, but the biochemical mechanism of LytB action remains unknown. Here we report the 1.65 Å crystal structure of the catalytic domain (residues Lys-375-Asp-658) of LytB (termed LytBCAT), excluding the choline binding domain. LytBCAT consists of three structurally independent modules: SH3b, WW, and GH73. These modules form a "T-shaped" pocket that accommodates a putative tetrasaccharide-pentapeptide substrate of peptidoglycan. Structural comparison and simulation revealed that the GH73 module of LytB harbors the active site, including the catalytic residue Glu-564. In vitro assays of hydrolytic activity indicated that LytB prefers the peptidoglycan from the lytB-deficient pneumococci, suggesting the existence of a specific substrate of LytB in the immature peptidoglycan. Combined with in vitro cell-dispersing and in vivo cell separation assays, we demonstrated that all three modules are necessary for the optimal activity of LytB. Further functional analysis showed that the full catalytic activity of LytB is required for pneumococcal adhesion to and invasion into human lung epithelial cells. Structure-based alignment indicated that the unique modular organization of LytB is highly conserved in its orthologs from Streptococcus mitis group and Gemella species. These findings provided structural insights into the pneumococcal cell wall remodeling and novel hints for the rational design of therapeutic agents against pneumococcal growth and thereby the related diseases.

Fucoidan induces apoptosis of HepG2 cells by down-regulating p-Stat3.

Fucoidan is one of the main bioactive components of polysaccharides. The current study was focused on the anti-tumor effects of fucoidan on human heptoma cell line HepG2 and the possible mechanisms. Fucoidan treatment resulted in cell cycle arrest and apoptosis of HepG2 cells in a dose-dependent manner detected by MTT assay, flow cytometry and fluorescent microscopy. The results of flow cytometric analysis revealed that fucoidan induced G2/M arrest in the cell cycle progression. Hoechst 33258 and Annexin V/PI staining results showed that the apoptotic cell number was increased, which was associated with a dose-dependent up-regulation of Bax and down-regulation of Bcl-2 and p-Stat3. In parallel, the up-regulation of p53 and the increase in reactive oxygen species were also observed, which may play important roles in the inhibition of HepG2 growth by fucoidan. In the meantime, Cyclin B1 and CDK1 were down-regulated by fucoidan treatment. Down-regulation of p-Stat3 by fucoidan resulted in apoptosis and an increase in ROS in response to fucoidan exposure. We therefore concluded that fucoidan induces apoptosis through the down-regulation of p-Stat3. These results suggest that fucoidan may be used as a novel anti-cancer agent for hepatocarcinoma.

Fucoidan induces G1 phase arrest and apoptosis through caspases-dependent pathway and ROS induction in human breast cancer MCF-7 cells.

Fucoidan is an active component of seaweed, which inhibits proliferation and induces apoptosis of several tumor cells while the detailed mechanisms underlying this process are still not clear. In this study, the effect of Fucoidan on the proliferation and apoptosis of human breast cancer MCF-7 cells and the molecular mechanism of Fucoidan action were investigated. Viable cell number of MCF-7 cells was decreased by Fucoidan treatment in a dose-dependent manner as measured by MTT assay. Fucoidan treatment resulted in G1 phase arrest of MCF-7 cells as revealed by flow cytometry, which was associated with the decrease in the gene expression of cyclin D1 and CDK-4. Annexin V/PI staining results showed that the number of apoptotic cells was associated with regulation of cytochrome C, caspase-8, Bax and Bcl-2 at transcriptional and translational levels. Both morphologic observation and Hoechst 33258 assay results confirmed the pro-apoptotic effect of Fucoidan. Meanwhile, the ROS production was also increased by Fucoidan treatment, which suggested that Fucoidan induced oxidative damage in MCF-7 cells. The results of present study demonstrated that Fucoidan could induce G1 phase arrest and apoptosis in MCF-7 cells through regulating the cell cycle and apoptosis-related genes or proteins expression, and ROS generation is also involved in these processes.