Double synergic chitosan-coated poly (lactic-co-glycolic) acid nanospheres loaded with nucleic acids as an intranasally administered vaccine delivery system to control the infection of foot-and-mouth disease virus.

BACKGROUND & AIMS: The spread of foot-and-mouth disease virus (FMDV) through aerosol droplets among cloven-hoofed ungulates in close contact is a major obstacle for successful animal husbandry. Therefore, the development of suitable mucosal vaccines, especially nasal vaccines, to block the virus at the initial site of infection is crucial. PATIENTS AND METHODS: Here, we constructed eukaryotic expression plasmids containing the T and B-cell epitopes (pTB) of FMDV in tandem with the molecular mucosal adjuvant Fms-like tyrosine kinase receptor 3 ligand (Flt3 ligand, FL) (pTB-FL). Then, the constructed plasmid was electrostatically attached to mannose-modified chitosan-coated poly(lactic-co-glycolic) acid (PLGA) nanospheres (MCS-PLGA-NPs) to obtain an active nasal vaccine targeting the mannose-receptor on the surface of antigen-presenting cells (APCs). RESULTS: The MCS-PLGA-NPs loaded with pTB-FL not only induced a local mucosal immune response, but also induced a systemic immune response in mice. More importantly, the nasal vaccine afforded an 80% protection rate against a highly virulent FMDV strain (AF72) when it was subcutaneously injected into the soles of the feet of guinea pigs. CONCLUSIONS: The nasal vaccine prepared in this study can effectively induce a cross-protective immune response against the challenge with FMDV of same serotype in animals and is promising as a potential FMDV vaccine.

Residue Analysis and the Effect of Preharvest Forchlorfenuron (CPPU) Application on On-Tree Quality Maintenance of Ripe Fruit in "Feizixiao" Litchi (Litchi chinensis Sonn.).

Litchi is a highly perishable fruit. Ripe litchi fruit loses quality quickly as they hang on tree, giving a very short hanging life and thus harvest period. This study attempted to explore the roles of cytokinin in regulating fruit ripening and senescence of litchi and examine the possibility of applying cytokinin in "on-tree storage" of the fruit. Exogenous cytokinin, forchlorfenuron (CPPU), was applied at 20 mg L-1 7 weeks after full bloom on litchi (Litchi chinensis cv. Feizixiao) fruit clusters. Color parameters, chlorophylls, anthocyanins, fruit and fruit part weights, total soluble solutes (TSSs), soluble sugars, organic acids, non-anthocyanin flavonoids, ethanol, and also CPPU residue in fruit were traced. CPPU residue was higher but decreased faster in the pericarp than in the aril, where it maintained < 10 µg kg-1. CPPU had no significant effect on fruit weight but tended to increase pericarp weight. The treatment suppressed chlorophyll loss and anthocyanin accumulation in the pericarp, increased non-anthocyanin flavonoids in the aril, but had no significant effects on non-anthocyanin flavonoids in the pericarp and total sugar and organic acids in the aril. As the commercially ripe fruit hanged on tree, TSSs, total sugar, and sucrose decreased with ethanol and acetic acid accumulation in the aril. CPPU significantly suppressed the loss of sucrose and total sugar and the accumulation of ethanol and acetic acid in the aril and inhibited malondialdehyde accumulation in the pericarp of the overripe fruit. Soluble invertase, alcohol dehydrogenase, and pyruvate decarboxylase (PDC) activity and gene expression in the aril were downregulated by CPPU. The results suggest that cytokinin partially suppresses the ripening process in litchi and is effective to slow quality loss in the overripe fruit on tree.

Chemical Compounds, Antioxidant Activities, and Inhibitory Activities Against Xanthine Oxidase of the Essential Oils From the Three Varieties of Sunflower (Helianthus annuus L.) Receptacles.

Background/Aim: Essential oils of sunflower receptacles (SEOs) have antibacterial and antioxidant potential. However, the differences of biological activities from the different varieties of sunflowers have not been studied till now. The purpose of this study was to compare the differences of chemical compounds, antioxidant activities, and inhibitory activities against xanthine oxidase (XO) of SEOs from the three varieties of sunflowers including LD5009, SH363, and S606. Methods: SEOs were extracted by using the optimal extraction conditions selected by response surface methodology (RSM). Chemical compounds of SEOs were identified from the three varieties of sunflowers by gas chromatography-mass spectrometry (GC-MS). Antioxidant activities of SEOs were detected by 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and iron ion reduction ability. Inhibitory activities of SEOs against XO were measured by using UV spectrophotometer. XO inhibitors were selected from the main chemical compounds of SEOs by the high-throughput selections and molecular simulation docking. Results: The extraction yields of SEOs from LD5009, SH363, and S606 were 0.176, 0.319, and 0.580%, respectively. A total of 101 chemical compounds of SEOs were identified from the three varieties of sunflowers. In addition, the results of inhibitory activities against XO showed that SEOs can reduce uric acid significantly. Eupatoriochromene may be the most important chemical compounds of SEOs for reducing uric acid. The results of antioxidant activities and inhibitory activities against XO showed that SEOs of LD5009 had the strongest antioxidant and XO inhibitory activities. The Pearson correlation coefficient (r > 0.95) showed that γ-terpinene, (E)-citral, and L-Bornyl acetate were highly correlated with the antioxidant activities and XO inhibitory ability. Conclusion: SEOs had antioxidant activities and XO inhibitory ability. It would provide more scientific information for utilization and selection of varieties of sunflowers, which would increase the food quality of sunflowers and incomes of farmers.

Precise diagnosis of three top cancers using dbGaP data.

The challenge of decoding information about complex diseases hidden in huge number of single nucleotide polymorphism (SNP) genotypes is undertaken based on five dbGaP studies. Current genome-wide association studies have successfully identified many high-risk SNPs associated with diseases, but precise diagnostic models for complex diseases by these or more other SNP genotypes are still unavailable in the literature. We report that lung cancer, breast cancer and prostate cancer as the first three top cancers worldwide can be predicted precisely via 240-370 SNPs with accuracy up to 99% according to leave-one-out and 10-fold cross-validation. Our findings (1) confirm an early guess of Dr. Mitchell H. Gail that about 300 SNPs are needed to improve risk forecasts for breast cancer, (2) reveal an incredible fact that SNP genotypes may contain almost all information that one wants to know, and (3) show a hopeful possibility that complex diseases can be precisely diagnosed by means of SNP genotypes without using phenotypical features. In short words, information hidden in SNP genotypes can be extracted in efficient ways to make precise diagnoses for complex diseases.

Chemical Composition and Antimicrobial and Antioxidant Activities of Essential Oil of Sunflower (Helianthus annuus L.) Receptacle.

Sunflower (Helianthus annuus L.) contains active ingredients, such as flavonoids, alkaloids and tannins. Nevertheless, few studies have focused on essential oil from the receptacle of sunflower (SEO). In this work, we investigated the chemical composition and antimicrobial and antioxidant activities of SEO. The yield of SEO was about 0.42% (v/w) by hydrodistillation. A total of 68 volatile components of SEO were putatively identified by gas chromatography-mass spectrometry (GC-MS). The main constituents of SEO were α-pinene (26.00%), verbenone (7.40%), terpinolene (1.69%) and α-terpineol (1.27%). The minimum inhibitory concentration (MIC) of SEO against P. aeruginosa and S. aureus was 0.2 mg/mL. The MIC of SEO against S. cerevisiae was 3.2 mg/mL. The MIC of SEO against E. coli and Candida albicans was 6.4 mg/mL. The results showed that SEO had high antibacterial and antifungal activities. Three different analytical assays (DPPH, ABTS and iron ion reducing ability) were used to determine the antioxidant activities. The results showed that SEO had antioxidant activities. To summarize, the results in this study demonstrate the possibility for the development and application of SEO in potential natural preservatives and medicines due to its excellent antimicrobial and antioxidant activities.

Mortality trend and predictors of mortality in dysphagic stroke patients postpercutaneous endoscopic gastrostomy.

BACKGROUND: Percutaneous endoscopic gastrostomy (PEG) feeding is widely used in stroke patients suffering from persistent dysphagia; however, predicting the risks and benefits of PEG insertion in the individual patient is difficult. The aim of our study was to investigate if candidate risk factors could predict short-term mortality risk in poststroke patients who had PEG tube insertion for persistent dysphagia. METHODS: This was a retrospective study of 3504 consecutive stroke patients admitted to two metropolitan hospitals during the period January 2005 to December 2013 and who also underwent PEG insertion for feeding due to persistent dysphagia. RESULTS: A total of 102 patients were included in the study. There were 22 deaths in 6 months after insertion of PEG tubes and 20 deaths of those occurred within 3 months post PEG. Those who survived beyond 6 months showed significantly lower mean age (75.9 ± 9.0 years vs. 83.0 ± 4.9 years, P < 0.001), a lower mean American Society of Anesthesia (ASA) score (3.04 ± 0.63 vs. 3.64 ± 0.58, P < 0.001) compared to nonsurvivors. In multiple Logistic, age (P = 0.004, odds ratio [OR] = 1.144; 95% confidence interval [CI]: 1.044-1.255); ASA (P = 0.002, OR = 5.065; 95% CI: 1.815-14.133) and albumin level pre-PEG insertion (P = 0.033, OR = 0.869; 95% CI: 0.764-0.988) were the independent determinants of mortality respectively. CONCLUSIONS: We propose that age, ASA score and albumin level pre-PEG insertion to be included as factors to assist in the selection of patients who are likely to survive more than 3 months post PEG insertion.

The effects of the context-dependent codon usage bias on the structure of the nsp1α of porcine reproductive and respiratory syndrome virus.

The information about the crystal structure of porcine reproductive and respiratory syndrome virus (PRRSV) leader protease nsp1α is available to analyze the roles of tRNA abundance of pigs and codon usage of the nsp1 α gene in the formation of this protease. The effects of tRNA abundance of the pigs and the synonymous codon usage and the context-dependent codon bias (CDCB) of the nsp1 α on shaping the specific folding units (α-helix, ß-strand, and the coil) in the nsp1α were analyzed based on the structural information about this protease from protein data bank (PDB: 3IFU) and the nsp1 α of the 191 PRRSV strains. By mapping the overall tRNA abundance along the nsp1 α, we found that there is no link between the fluctuation of the overall tRNA abundance and the specific folding units in the nsp1α, and the low translation speed of ribosome caused by the tRNA abundance exists in the nsp1 α. The strong correlation between some synonymous codon usage and the specific folding units in the nsp1α was found, and the phenomenon of CDCB exists in the specific folding units of the nsp1α. These findings provide an insight into the roles of the synonymous codon usage and CDCB in the formation of PRRSV nsp1α structure.

Patterns and influencing factor of synonymous codon usage in porcine circovirus.

BACKGROUND: Analysis of codon usage can reveal much about the molecular evolution of the viruses. Nevertheless, little information about synonymous codon usage pattern of porcine circovirus (PCV) genome in the process of its evolution is available. In this study, to give a new understanding on the evolutionary characteristics of PCV and the effects of natural selection from its host on the codon usage pattern of the virus, Patterns and the key determinants of codon usage in PCV were examined. METHODS: We carried out comprehensive analysis on codon usage pattern in the PCV genome, by calculating relative synonymous codon usage (RSCU), effective number of codons (ENC), dinucleotides and nucleic acid content of the PCV genome. RESULTS: PCV genomes have relatively much lower content of GC and codon preference, this result shows that nucleotide constraints have a major impact on its synonymous codon usage. The results of the correspondence analysis indicate codon usage patterns of PCV of various genotypes, various subgenotypes changed greatly, and significant differences in codon usage patterns of Each virus of Circoviridae.There is much comparability between PCV and its host in their synonymous codon usage, suggesting that the natural selection pressure from the host factor also affect the codon usage patterns of PCV. In particular, PCV genotype II is in synonymous codon usage more similar to pig than to PCV genotype I, which may be one of the most important molecular mechanisms of PCV genotype II to cause disease. The calculations results of the relative abundance of dinucleotides indicate that the composition of dinucleotides also plays a key role in the variation found in synonymous codon usage in PCV. Furthermore, geographic factors, the general average hydrophobicity and the aromaticity may be related to the formation of codon usage patterns of PCV. CONCLUSION: The results of these studies suggest that synonymous codon usage pattern of PCV genome are the result of interaction between mutation pressure and natural selection from its host. The information from this study may not only have theoretical value in understanding the characteristics of synonymous codon usage in PCV genomes, but also have significant value for the molecular evolution of PCV.

Identification of H-2d restricted T cell epitope of foot-and-mouth disease virus structural protein VP1.

BACKGROUND: Foot-and-mouth disease (FMD) is a highly contagious and devastating disease affecting livestock that causes significant financial losses. Therefore, safer and more effective vaccines are required against Foot-and-mouth disease virus(FMDV). The purpose of this study is to screen and identify an H-2d restricted T cell epitope from the virus structural protein VP1, which is present with FMD. We therefore provide a method and basis for studying a specific FMDV T cell epitope. RESULTS: A codon-optimized expression method was adopted for effective expression of VP1 protein in colon bacillus. We used foot-and-mouth disease standard positive serum was used for Western blot detection of its immunogenicity. The VP1 protein was used for immunizing BALB/c mice, and spleen lymphocytes were isolated. Then, a common in vitro training stimulus was conducted for potential H-2Dd, H-2Kd and H-2Ld restricted T cell epitope on VP1 proteins that were predicted and synthesized by using a bioinformatics method. The H-2Kd restricted T cell epitope pK1 (AYHKGPFTRL) and the H-2Dd restricted T cell epitope pD7 (GFIMDRFVKI) were identified using lymphocyte proliferation assays and IFN-γ ELISPOT experiments. CONCLUSIONS: The results of this study lay foundation for studying the FMDV immune process, vaccine development, among other things. These results also showed that, to identify viral T cell epitopes, the combined application of bioinformatics and molecular biology methods is effective.

[Distribution characteristics of delta13C values in different organs of Abies georgei growing at alpine timberline].

Based on the analysis of the distribution characteristics of delta13C values in the needle, twig, branch, trunk, and root of different age Abies georgei growing at the timberline of Sergyemla Mountain on the southeast edge of Tibetan Plateau, this paper studied the process or extent of post-photosynthetic delta13C fractionation and its affecting factors. The results showed that the organ-specific difference in delta13C values was highly significant (P < 0.001), with the sequence of trunk (-24.19 per thousand +/- 0.34 per thousand) > branch (-24.56 per thousand +/- 0.62 per thousand) > root (-25.05 per thousand +/- 1.08 per thousand) > twig (-25.12 per thousand +/- 0.54 per thousand) > needle (-7.25 per thousand +/- 0.63 per thousand), which suggested that an obvious post-photosynthetic delta13C fractionation was existed between photosynthetic and non-photosynthetic organs. With increasing age of needle and twig, the delta13C value in needle decreased significantly, while that in twig showed a reverse pattern (P < 0.01). The delta13C value in needle increased significantly (P < 0.01) from lower canopy to higher canopy, whereas no significant difference (P > 0.05) of delta13C value in twig was observed among different canopy heights. A significant vertical gradient of delta13C value existed in the branches at a distance of 2.5 m from trunk (P < 0.01), but disappeared at a distance of 1.5 m or 0.5 m. At the same canopy height, the delta13C value in twig decreased with increasing distance from trunk, which was most obvious in the twigs of middle and lower canopies. All of these suggested that post-photosynthetic delta13C fractionation occurred in alpine A. georgei, and the carbon need for the growth of height-specific tree stems or branches was not wholly supplied by the corresponding segment of the tree crown at the same height.

Expression, purification and bioactivity of human augmenter of liver regeneration.

AIM: To construct the expression vectors for prokaryotic and eukaryotic human augmenter of liver regeneration (hALR) and to study their biological activity. METHODS: hALRcDNA clone was obtained from plasmid pGEM-T-hALR, and cDNA was subcloned into the prokatyotic expression vector pGEX-4T-2. The recombinant vector and pGEX-4T-2hALR were identified by enzyme digestion and DNA sequencing and transformed into E coli JM109. The positively selected clone was induced by the expression of GST-hALR fusion protein with IPTG, then the fusion protein was purified by glutathine s-transferase (GST) sepharose 4B affinity chromatography, cleaved by thrombin and the hALR monomer was obtained and detected by measuring H thymidine incorporation. RESULTS: The product of PCR from plasmid pGEM-T-hALR was examined by 1.5% sepharose electrophoresis. The specific strap was coincident with the theoretical one. The sequence was accurate and pGEX-4T-hALP digested by enzymes was coincident with the theoretical one. The sequence was accurate and the fragment was inserted in the positive direction. The recombinant vector was transformed into E coli JM109. SDS-PAGE proved that the induced expressive fusion protein showed a single band with a molecular weight of 41 kDa. The product was purified and cleaved. The molecular weights of GST and hALR were 26 kDa, 15 kDa respectively. The recombinant fusion protein accounted for 31% of the total soluble protein of bacterial lysate. HALR added to the culture medium of adult rat hepatocytes in primary culture and HepG2 cell line could significantly enhance the rate of DNA synthesis compared to the relevant control groups (P < 0.01). CONCLUSION: Purified hALR has the ability to stimulate DNA synthesis of adult rat hepatocytes in primary culture and HepG2 cells in vitro, and can provide evidence for its clinical application.

Diagnosis and treatment of penetrating anorectal wounds.

OBJECTIVE: To research the diagnosis and effective treatment of penetrating anorectal wounds. METHODS: Retrospective analysis was done in 16 cases of penetrating anorectal wounds from 1985 to 2004. Debridement and suture of anorectal and vesical wounds, effective diversion of fecal and urinary stream and sufficient presacral drainage were performed in all cases. RESULTS: All the 16 cases were cured. Among them, 2 cases with infection in presacral space were cured by sufficient drainage after operation, one case was cured by secondary repair after anal sphincter was repaired unsuccessfully and one case with rectovesical fistula was cured with conservative treatment. None of them suffered from complications such as anal stenosis, dysuria or impotence etc. CONCLUSIONS: For penetrating anorectal wound, to master early recognition of concomitant injures, to select appropriate surgical intervention and to strengthen perioperative treatment are the keys to improve the curative effects.

[Study on the strategy of interrupting schistosomiasis transmission in a hilly new endemic area of Taoyuan County].

OBJECTIVE: To develop a strategy for interrupting the transmission of schistosomiasis japonica in a hilly new endemic area. METHODS: Since 1996, chemotherapy with praziquantel (adult 40 mg/kg, child 50 mg/kg, cattle 30 mg/kg, once a year) on human beings in Taoyuan County who had ever contacted with infectious water and cattle which were herded in endemic situation was the major intervention, with focal control of Oncomelania snails in susceptible areas as supplementary one. RESULTS: The positive rate of stool examination for schistosomiasis in human and cattle reduced from 5.69% and 6.76% in 1996 to 0.04% and 0 in 2005 respectively. The positive rate of indirect hemagglutination test (IHA) in human dropped from 7.45% in 1996 to 1.61% in 2004. Though living snails were still found in most habitats, the density of infected snails decreased from 0.0036/0.11m2 in 1997 to 0 in 2005 and no infected snails were found since 2000. CONCLUSION: Due to less movement of human and cattle populations and the hilly area relatively isolated, chemotherapy combined with focal mollusciciding have been highly effective in eliminating the infection sources and interrupting transmission of schistosomiasis.

[N II ion spectra related to lightning discharges].

Appling the atomic structure theory to the research field of physical processes of lightning discharges, parameters such as wavelengths, oscillator strengths, transition probabilities and excitation energy of upper levels have been calculated for the transitions of N II ions related to lightning discharges. Large-scale multi-configuration Dirac-Fock wavefunctions were applied to include the most important effects of relativity, correlation, and rearrangement of the electron density within the same (computational) model. More detailed identification than ever for lightning spectra has been done, and reference data have been provided for further theoretic and experimental works on the physical mechanism of lightning discharges.