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.

Comparative Study of the Genetic Diversity, Antimicrobial Resistance, and Pathogenicity of Aeromonas Isolates from Clinical Patients and Healthy Individuals.

OBJECTIVE: This study was performed to compare the genetic diversity, virulence, and antimicrobial resistance of Aeromonas strains isolated from patients and healthy individuals. METHODS: A total of 38 clinical strains and 19 strains from healthy individuals were isolated from the samples collected in Ma'anshan City, Anhui Province. Their taxonomy was investigated using concatenated gyrB- cpn60 sequences, and their resistance to 12 antibiotics was evaluated. The pathogenicity of these strains was examined through beta-hemolysis, protease activity, and virulence gene assays. RESULTS: The 57 Aeromonas strains were divided into 55 sequence types. Of these types, 21 were novel, suggesting that their genetic diversity was high. These Aeromonas isolates could be divided into 7 species, and the positive rates of beta-hemolysis and protease activity were 49.1% and 73.7%, respectively. The detection rate of clinical patients in terms of beta-hemolysis and protease activity was higher than that of healthy individuals. Among the four most common Aeromonas strains, A. dhakensis had the highest detection rate of virulence genes. The multidrug resistance rate of the clinical isolates was much higher than that of the strains isolated from healthy individuals. CONCLUSIONS: The taxonomy, virulence properties, and antibiotic resistance of Aeromonas isolates from patients differ from those of the isolates from healthy individuals.

Genetic Diversity, Antimicrobial Resistance, and Virulence Genes of Aeromonas Isolates from Clinical Patients, Tap Water Systems, and Food.

OBJECTIVE: This study aimed to evaluate the genetic diversity, virulence, and antimicrobial resistance of Aeromonas isolates from clinical patients, tap water systems, and food. METHODS: Ninety Aeromonas isolates were obtained from Ma'anshan, Anhui province, China, and subjected to multi-locus sequence typing (MLST) with six housekeeping genes. Their taxonomy was investigated using concatenated gyrB-cpn60 sequences, while their resistance to 12 antibiotics was evaluated. Ten putative virulence factors and several resistance genes were identified by PCR and sequencing. RESULTS: The 90 Aeromonas isolates were divided into 84 sequence types, 80 of which were novel, indicating high genetic diversity. The Aeromonas isolates were classified into eight different species. PCR assays identified virulence genes in the isolates, with the enterotoxin and hemolysin genes act, aerA, alt, and ast found in 47 (52.2%), 13 (14.4%), 22 (24.4%), and 12 (13.3%) of the isolates, respectively. The majority of the isolates (≥ 90%) were susceptible to aztreonam, imipenem, cefepime, chloramphenicol, gentamicin, tetracycline, and ciprofloxacin. However, several resistance genes were detected in the isolates, as well as a new mcr-3 variant. CONCLUSIONS: Sequence type, virulence properties, and antibiotic resistance vary in Aeromonas isolates from clinical patients, tap water systems, and food.

Development of a New RT-PCR with Multiple Primers for Detecting Southern African Territories Foot-and-mouth Disease Viruses.

INTRODUCTION: The extremely high genetic variation and the continuously emerging variants of foot-and-mouth disease virus (FMDV) of Southern African Territory (SAT) serotypes including SAT1, SAT2, and SAT3 make it necessary to develop a new RT-PCR for general use for monitoring viruses based on the updated genome information. MATERIAL AND METHODS: A FMDV SAT-D8 one-step RT-PCR was established based on the 1D2A2B genes of the SAT serotype viruses with a multiplex primer set. FMDV A, O, C, and Asia 1 serotypes, other vesicular disease viruses, inactivated SAT viruses, and 125 bovine, ovine, caprine and porcine tissue samples collected from the Chinese mainland were included for evaluating the assay. RESULTS: The new RT-PCR was proven to be specific without cross-reactions with Eurasian FMDV, swine vesicular disease virus (SVDV), Seneca valley virus (SVV), or other common viral pathogens of cattle, sheep, goat, and pig. An around 257 bp-sized amplicon clearly appeared when the inactivated SAT viruses were detected. However, all 125 samples collected from FMDV-susceptible animals from the Chinese mainland which has not known SAT epidemics showed negative results. CONCLUSIONS: A FMDV SAT-D8 one-step RT-PCR is a promising method for primary screening for FMDV SAT serotypes.

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.

Strontium fructose 1,6-diphosphate prevents bone loss in a rat model of postmenopausal osteoporosis via the OPG/RANKL/RANK pathway.

AIM: To evaluate the protective effects of strontium fructose 1,6-diphosphate (FDP-Sr), a novel strontium salt that combined fructose 1,6-diphosphate (FDP) with strontium, on bone in an ovariectomy-induced model of bone loss. METHODS: Eighty female Sprague-Dawley rats were ovariectomized (OVX) or sham-operated. Three months later, the rats were assigned to six groups (10 for each): sham-operated, OVX control, OVX+FDP-Sr (110, 220, or 440 mg/kg), or OVX+strontium ranelate (SR, 180 mg/kg). Drugs were administered orally for 3 months. When the treatment was terminated, the following parameters were assessed: bone mineral density (BMD), the biomechanical properties of the femur and lumbar vertebrae, trabecular histomorphology, serum phosphorus, calcium, bone-specific alkaline phosphatase (B-ALP), tartrate-resistant acid phosphatase 5b (TRACP5b), N-telopeptide of type I collagen (NTx) and a series of markers for oxidative stress. Receptor activator of NF-κB ligand (RANKL) and osteoprotegerin (OPG) levels in serum were measured using ELISA and their gene expression levels in the bone were measured using R-T PCR. RESULTS: Treatment with FDP-Sr (220 or 440 mg/kg) or SR (180 mg/kg) significantly increased the BMD and improved the bone microarchitecture and bone strength in OVX rats. The treatments also decreased in the levels of H(2)O(2) and MDA, restored the CAT level in serum and bone marrow, increased the serum B-ALP and decreased NTx and TRACP 5b in OVX rats. Treatment with FDP-Sr decreased the RANKL level, and increased the OPG level in serum in a dose-dependent manner. It also significantly down-regulated the RANKL expression and up-regulated OPG expression in bone marrow. CONCLUSION: FDP-Sr may be an effectve treatment for postmenopausal osteoporosis that acts, in part, via a decrease in osteoclastogenesis through the OPG\RANKL\RANK pathway.

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.

GC-TOF/MS-based metabolomic profiling of estrogen deficiency-induced obesity in ovariectomized rats.

AIM: To explore the alteration of endogenous metabolites and identify potential biomarkers using metabolomic profiling with gas chromatography coupled a time-of-flight mass analyzer (GC/TOF-MS) in a rat model of estrogen-deficiency-induced obesity. METHODS: Twelve female Sprague-Dawley rats six month of age were either sham-operated or ovariectomized (OVX). Rat blood was collected, and serum was analyzed for biomarkers using standard colorimetric methods with commercial assay kits and a metabolomic approach with GC/TOF-MS. The data were analyzed using multivariate statistical techniques. RESULTS: A high body weight and body mass index inversely correlated with serum estradiol (E2) in the OVX rats compared to the sham rats. Estrogen deficiency also significantly increased serum total cholesterol, triglycerides, and low-density lipoprotein cholesterol. Utilizing GC/TOF-MS-based metabolomic analysis and the partial least-squares discriminant analysis, the OVX samples were discriminated from the shams. Elevated levels of cholesterol, glycerol, glucose, arachidonic acid, glutamic acid, glycine, and cystine and reduced alanine levels were observed. Serum glucose metabolism, energy metabolism, lipid metabolism, and amino acid metabolism were involved in estrogen-deficiency-induced obesity in OVX rats. CONCLUSION: The series of potential biomarkers identified in the present study provided fingerprints of rat metabolomic changes during obesity and an overview of multiple metabolic pathways during the progression of obesity involving glucose metabolism, lipid metabolism, and amino acid metabolism.

[Synthesis and biological evaluation of 3-aromatic Shiff base-5-fluoroindol-2-one derivatives].

Based on the structure of 5-fluoroindol-2-one and fragments from thirteen multi-target tyrosine kinase inhibitors which have been marketed or in the phase of clinical research, eleven 3-aromatic Shiff base-5-fluoroindol-2-one derivatives were designed and synthesized. Their structures were identified by 1H NMR, MS and elemental analysis. In vitro antitumor bioactivities evaluation was done by MTT method. It was shown that most of synthesized compounds had antitumor activities and compounds 1b, 1g, 1i and 1h were better than or equal to the antitumor activity of positive control.

[Similarity analysis of FTIR of Lapis Micae Aureum].

Similarity analysis of FTIR of Lapis Micae Aureum was carried out to find out the relationship between similarity of infrared spectra and the quality of medicine samples, and try to provide a new method for its quality assessment. FTIR was used to analyze Lapis Micae Aureum samples. Then 6 samples with good quality were picked up to establish a reference infrared spectra by their infrared spectra. Correlation coefficient method and the included angle cosine method were used to calculate the similarity between sample's infrared spectra and the reference infrared spectra. For all those 19 samples with characters in accordance with Ch. P, the similarity is above 0.94, and for the others the similarity is less than 0.94. Although some samples' source meets the requirement of Ch. P, but with poor quality by traditional experience, the similarity is lower than those of good quality. It was concluded that the similarity of infrared spectra of Lapis Micae Aureum is closely related to the quality of medicines. As a result, similarity analysis of FTIR of Lapis Micae Aureum is reliable, and can be used for its quality assessment.

Screening and identification of B cell epitopes of structural proteins of foot-and-mouth disease virus serotype Asia1.

The objective of this study was to screen and identify the B cell epitopes of structural proteins of foot-and-mouth disease virus (FMDV) serotype Asia1. The complete amino acid sequence of all the four structural proteins (P1 region) was analyzed using the DNAStar Protean system. Seventeen peptides were predicted and selected as potential B cell epitopes. The potential B cell epitope genes were cloned into the pGEX-6P-1 plasmid, then expressed and purified. The resulting 17 glutathione S-transferase (GST) fusion peptides were detected by Western blot and ELISA for evaluation of their antigenicity. Six of the 17 fusion peptides were identified successfully by sera from rabbits immunized with the purified P1 polyprotein of FMDV type Asia1. The six fusion proteins were epi1-1 (VP1:(1)TTTTGESADPVT(12)), epi1-2 (VP1:(17)NYGGETQTARRLH(29)), epi1-6 (VP1:(194)TTQDRRKQEIIAPEKQTL(211)), epi2-2 (VP2:(40)EDAVSGPNTSG(50)), epi3-1 (VP3:(26)YGKVSNPPRTSFPG(39)), and epi4-2 (VP4:(30)YQNSMDTQLGDN(41)). The results of this study lay a foundation for further study of the structure and function of the structural proteins and may aid in the design of an epitope vaccine against foot-and-mouth disease (FMD) type Asia1. This study has also shown that the bioinformatics method, in combination with molecular biology methods can be used to map the B cell epitopes on viral proteins.

[Construction and identification of infectious molecular clone of foot-and-mouth disease virus strain O/CHINA/99].

Nine primers were designed for the full-length genome of O/CHINA/99 and each sequence fragment was obtained by RT-PCR, and cloned into pOK12 vecter, the full-length genome cDNA clone of O/CHINA/99 was identified by restriction enzymes digestion, PCR, and the whole genome sequencing. The results showed that the O/CHINA/99 whole genome was formed with the length of 8200 nt. The nucleotide sequence of the full-length cDNA shared 99.1% homology with its prototype. RNA synthesized in vitro by means of a bacteriophage T7 promter inserted in front of the cDNA led to the production of infectious particle upon transfection of BHK-21 cell using lipofectamine reagent, as shown by cytopathic effects. The rescued virus had high pathogenicity in mice by endermic infection too. All the results showed that an infectious molecular clone was successfully constructed and rescued virus could be obtained.

Phenyl N-(4-methoxy-phen-yl)carbamate.

The asymmetric unit of the title compound, C(14)H(13)NO(3), contains two crystallographically independent mol-ecules, in which the aromatic rings are oriented at dihedral angles of 75.64 (3) and 83.14 (3)°. An N-H⋯O hydrogen bond links the two mol-ecules. Weak intramolecular C-H⋯O inter-actions are observed in the two mol-ecules. In the crystal structure, inter-molecular N-H⋯O and C-H⋯O inter-actions link the mol-ecules into a two-dimensional network.

Phenyl N-(p-tol-yl)carbamate.

The asymmetric unit of the title compound, C(14)H(13)NO(2), contains two crystallographically independent mol-ecules, in which the aromatic rings are oriented at dihedral angles of 59.01 (3) and 56.98 (3)°. In the crystal structure, inter-molecular N-H⋯O hydrogen bonds link the mol-ecules into chains.

[Isolation and characterization of Shewanella spp. from patients of food poisoning].

OBJECTIVE: To identify the isolates of Shewanella spp. from specimens of food poisoning based on biological and biochemical analysis. METHODS: Strains were obtained from the investigation on two food poisoning episodes in September and October, 2007 in Ma'anshan city, Anhui province. In accordance with the national standard protocol (GB/T 4789), all specimens were enriched and isolated on selective medium, and the suspected strains were identified by the VITEK-32 and API20E systems. For Shewanella spp. identified by the biochemical system, more characteristics were analyzed using auxiliary biochemical, growth, hemolytic and drug-resistance tests. DNAs of Shewanella spp. were extracted, 16S rDNA was PCR amplified and sequenced with universal 16S rDNA primers. Phylogenetic tree was constructed with MEGA 4.0. RESULTS: After enrichment, all specimens were inoculated to selective medium and Shewanella spp. strains were isolated from 8 samples with single colony on both TCBS and BP media. The characteristics of growth in the Triple Sugar Iron (TSI) agar appeared to have had hydrogen sulfide production but no gas production or positive oxidase. No Shewanella spp. strain was detected in WS, SS and EMB media. The 8 strains were identified as Shewanella algae (S. algae) or Shewanella putrefaciens (S. putrefaciens) by VITEK-32, as S. putrefaciens by API20E system. No other enteropathogenic bacteria, including Vibrio cholerae, Salmonella, Vibrio parahaemolyticus, Proteus vulgaris or Staphylococcus aureus, were detected from those 8 samples. From 16S rDNA phylogenetic trees, 7 out of 8 Shewanella spp. were identified as S. algae, 1 as S. putrefaciens. CONCLUSION: Strains of Shewanella spp. were isolated from samples of the food poisoning episodes, providing a possible clue to investigate the role of Shewanella spp. on food poisoning.

[Protective immune response of guinea pigs against challenge with foot and mouth disease virus by immunization with foliar extracts from transgenic tomato plants expressing the FMDV structural protein VP1].

The plant constitutive expression vector pBin438/VP1 for VP1 gene of foot-and-mouth disease virus strain O/ China/99 was constructed. Mediated with Agrobacterium tumefaciens GV3101 harboring pBin438/VP1, VP1 gene was transferred into cotyledons of tomato. After selected by Kanamysin, sixty resistant lines were obtained. The integration and transcription of the VP1 gene in transformed plants was detected by PCR and RT-PCR. After being detected by sandwich-ELISA assays, about 40% transformed plants confirmed to express the recombinant protein. The leave extracts of two positive lines were respectively emulsified in Freund's adjuvant and guinea pigs were intramuscular inoculation at days 0, 15 and 30d. According to the sera antibody levels and the protection of the vaccinated guinea pigs against challenge with 100ID50 FMDV, probed into the immunogenicity of the target protein expressed in transgenic plants. Experimental results showed that the plant expression vector was successfully constructed. PCR and RT-PCR analyses confirmed VP1 gene was transformed into tomato plants and got expression at the transcription levels. The expressed VP1 protein of FMDV, which was identified by ELISA and Western blot, can be specifically recognized by polyclonal antibodies against FMDV. Indirect-ELISA antibody titers reached 1:64 twenty-one days after the third inoculation. In the challenge test, the protection against FMDV challenge in two groups was 80% and 40% respectively. The immunization test in guinea pigs indicated that the expression product of transgenic tomato plants had immunogenicity and could effectively induce the specific antibodies against FMDV.