Acaricidal properties of an Ailanthus altissima bark extract against Psoroptes cuniculi and Sarcoptes scabiei var. cuniculi in vitro

The potential acaricidal properties of an Ailanthus altissima bark extract were assessed against two common species of animal ectoparasitic mites, Psoroptes cuniculi and Sarcoptes scabiei var. cuniculi, in vitro. A. altissima bark extract was obtained by ethanol thermal circumfluence and tested at four concentrations (1.0, 0.5, 0.25 and 0.125 g/ml) on mites collected from rabbits. Compared to the fenvalerate treatment group, the A. altissima bark exhibited significant acaricidal properties for both mite species treated. The extract of concentrations of 1.0, 0.5 and 0.25 g/ml killed all tested S. scabiei within 7 h, however, only 1.0 and 0.5 g/ml of extract killed all treated P. cuniculi. The median lethal time (LT₅₀) values at 1, 0.5 and 0.25 g/ml were 0.60, 0.78, 1.48 h for S. scabiei and 0.74, 1.29, 3.33 h for P. cuniculi. The median lethal concentration (LC₅₀) for P. cuniculi was approximately 1.6 times that for S. scabiei var. cuniculi at 4 h. The extract showed stronger toxicity against S. scabiei than against P. cuniculi. Mortality rates increased with increasing concentration of extract administered and with increasing time post-treatment, indicating that the acaricidal activity of A. altissima bark extract is both time-dependent and dose-dependent. This is the first report on acaricidal activity of A. altissima against P. cuniculi and S. scabiei var. cuniculi. It indicates that A. altissima contain potential acaricidal compounds. Our study is the first step to develop potentially novel compounds from A. altissima for the effective control of mites in livestock.     

Comparative genomic analysis of clinical and environmental strains provides insight into the pathogenicity and evolution of Vibrio parahaemolyticus

Background

Vibrio parahaemolyticus is a Gram-negative halophilic bacterium. Infections with the bacterium could become systemic and can be life-threatening to immunocompromised individuals. Genome sequences of a few clinical isolates of V. parahaemolyticus are currently available, but the genome dynamics across the species and virulence potential of environmental strains on a genome-scale have not been described before.

Results

Here we present genome sequences of four V. parahaemolyticus clinical strains from stool samples of patients and five environmental strains in Hong Kong. Phylogenomics analysis based on single nucleotide polymorphisms revealed a clear distinction between the clinical and environmental isolates. A new gene cluster belonging to the biofilm associated proteins of V. parahaemolyticus was found in clincial strains. In addition, a novel small genomic island frequently found among clinical isolates was reported. A few environmental strains were found harboring virulence genes and prophage elements, indicating their virulence potential. A unique biphenyl degradation pathway was also reported. A database for V. parahaemolyticus (http://kwanlab.bio.cuhk.edu.hk/vp) was constructed here as a platform to access and analyze genome sequences and annotations of the bacterium.

Conclusions

We have performed a comparative genomics analysis of clinical and environmental strains of V. parahaemolyticus. Our analyses could facilitate understanding of the phylogenetic diversity and niche adaptation of this bacterium.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2164-15-1135) contains supplementary material, which is available to authorized users.     

A Systematic Review of Scope and Quality of Health Economic Evaluation Studies in Vietnam

Introduction

The application of health economic evaluation (HEE) evidence can play an important role in strategic planning and policy making. This study aimed to assess the scope and quality of existing research, with the goal of elucidating implications for improving the use of HEE evidence in Vietnam.

Methods

A comprehensive search strategy was developed to search medical online databases (Medline, Google Scholar, and Vietnam Medical Databases) to select all types of HEE studies except cost-only analyses. Two researchers assessed the quality of selected studies using the Quality of Health Economic Studies (QHES) instrument.

Results

We selected 26 studies, including 6 published in Vietnam. The majority of these studies focused on infectious diseases (14 studies), with HIV being the most common topic (5 studies). Most papers were cost-effectiveness studies that measured health outcomes using DALY units. Using QHES, we found that the overall quality of HEE studies published internationally was much higher (mean score 88.7+13.3) than that of those published in Vietnam (mean score 67.3+22.9). Lack of costing perspectives, reliable data sources and sensitivity analysis were the main shortcomings of the reviewed studies.

Conclusion

This review indicates that HEE studies published in Vietnam are limited in scope and number, as well as by several important technical errors or omissions. It is necessary to formalize the process of health economic research in Vietnam and to institutionalize the links between researchers and policy-makers. Additionally, the quality of HEE should be enhanced through education about research techniques, and the implementation of standard HEE guidelines.     

Suppression of the PI3K Pathway In Vivo Reduces Cystitis-Induced Bladder Hypertrophy and Restores Bladder Capacity Examined by Magnetic Resonance Imaging

This study utilized magnetic resonance imaging (MRI) to monitor the real-time status of the urinary bladder in normal and diseased states following cyclophosphamide (CYP)-induced cystitis, and also examined the role of the phosphoinositide 3-kinase (PI3K) pathway in the regulation of urinary bladder hypertrophy in vivo. Our results showed that under MRI visualization the urinary bladder wall was significantly thickened at 8 h and 48 h post CYP injection. The intravesical volume of the urinary bladder was also markedly reduced. Treatment of the cystitis animals with a specific PI3K inhibitor {"type":"entrez-nucleotide","attrs":{"text":"LY294002","term_id":"1257998346","term_text":"LY294002"}}LY294002 reduced cystitis-induced bladder wall thickening and enlarged the intravesical volumes. To confirm the MRI results, we performed H&E stain postmortem and examined the levels of type I collagen by real-time PCR and western blot. Inhibition of the PI3K in vivo reduced the levels of type I collagen mRNA and protein in the urinary bladder ultimately attenuating cystitis-induced bladder hypertrophy. The bladder mass calculated according to MRI data was consistent to the bladder weight measured ex vivo under each drug treatment. MRI results also showed that the urinary bladder from animals with cystitis demonstrated high magnetic signal intensity indicating considerable inflammation of the urinary bladder when compared to normal animals. This was confirmed by examination of the pro-inflammatory factors showing that interleukin (IL)-1α, IL-6 and tumor necrosis factor (TNF)α levels in the urinary bladder were increased with cystitis. Our results suggest that MRI can be a useful technique in tracing bladder anatomy and examining bladder hypertrophy in vivo during disease development and the PI3K pathway has a critical role in regulating bladder hypertrophy during cystitis.     

Phylogenetic studies of three sinipercid fishes (Perciformes: Sinipercidae) based on complete mitochondrial DNA sequences

The sinipercids are a group of 12 species of freshwater percoid fish endemic to East Asia and their phylogenetic placements have perplexed generations of taxonomists. We cloned and sequenced the complete mitochondrial DNA (mtDNA) of three sinipercid fishes (Siniperca chuatsi, S. kneri, and S. scherzeri) to characterize and compare their mitochondrial genomes. The mitochondrial genomes of S. chuatsi, S. kneri, and S. scherzeri were 16,496, 17,002, and 16,585?bp in length, respectively. The organization of the three mitochondrial genomes is similar to those reported from other fish mitochondrial genomes, which contains 37 genes (13 protein-coding genes, 2 ribosomal RNAs, and 22 transfer RNAs) and a major non-coding control region. Among the 13 protein-coding genes of all the three sinipercid fishes, three reading-frame overlaps were found on the same strand. There is an 81-bp tandem repeat cluster at the end of CSB-3 in the S. scherzeri control region. The complete mitochondrial genomes of the three sinipercids should be useful for the evolutionary studies of sinipercids and other vertebrate species.     

Chimeric piggyBac transposases for genomic targeting in human cells

Integrating vectors such as viruses and transposons insert transgenes semi-randomly and can potentially disrupt or deregulate genes. For these techniques to be of therapeutic value, a method for controlling the precise location of insertion is required. The piggyBac (PB) transposase is an efficient gene transfer vector active in a variety of cell types and proven to be amenable to modification. Here we present the design and validation of chimeric PB proteins fused to the Gal4 DNA binding domain with the ability to target transgenes to pre-determined sites. Upstream activating sequence (UAS) Gal4 recognition sites harbored on recipient plasmids were preferentially targeted by the chimeric Gal4-PB transposase in human cells. To analyze the ability of these PB fusion proteins to target chromosomal locations, UAS sites were randomly integrated throughout the genome using the Sleeping Beauty transposon. Both N- and C-terminal Gal4-PB fusion proteins but not native PB were capable of targeting transposition nearby these introduced sites. A genome-wide integration analysis revealed the ability of our fusion constructs to bias 24% of integrations near endogenous Gal4 recognition sequences. This work provides a powerful approach to enhance the properties of the PB system for applications such as genetic engineering and gene therapy.     

Effectiveness of the cleaning performance of the bacterial strain <Emphasis Type="Italic">Acinetobacter</Emphasis> sp. SG06-02 in the petroleum hydrocarbon-polluted intestine of clams

Summary A petroleum-degrading bacterial strain Acinetobacter sp. SG06-02 in the oil-polluted intestine of shellfish clam was previously isolated in our laboratory. In this study, the effectiveness of using its cleaning performance on petroleum pollution was investigated. The accumulation of petroleum in the intestine of Ruditapes philippinarum was determined by a UV spectrophotometer. The survival and growth of the SG06-02 strain in the intestine of Ruditapes philippinarum after oil pollution were examined. The concentration of oil accumulated in the Ruditapes philippinarum intestine quickly rises to 254.97 mg/kg within 12 h after placing the clam in the petroleum-polluted seawater tank. After decontaminating using Acinetaobacter we found that the concentration of petroleum inside the Ruditapes philippinarum declined significantly. The results of the cleaning experiments showed that the degradation activity by using bioremediation method of the strain SG06-02 increased 12.8∼30.2% compared to using clean seawater in 4 days. This research indicated that the petroleum degrading bacteria could survive and was effective in cleaning oily pollutants in the seashell.     

A dual-tag microarray platform for high-performance nucleic acid and protein analyses

DNA microarrays serve to monitor a wide range of molecular events, but emerging applications like measurements of weakly expressed genes or of proteins and their interaction patterns will require enhanced performance to improve specificity of detection and dynamic range. To further extend the utility of DNA microarray-based approaches we present a high-performance tag microarray procedure that enables probe-based analysis of as little as 100 target cDNA molecules, and with a linear dynamic range close to 10⁵. Furthermore, the protocol radically decreases the risk of cross-hybridization on microarrays compared to current approaches, and it also allows for quantification by single-molecule analysis and real-time on-chip monitoring of rolling-circle amplification. We provide proof of concept for microarray-based measurement of both mRNA molecules and of proteins, converted to tag DNA sequences by padlock and proximity probe ligation, respectively.     

Transgenic breeding of anti-Bombyx mori L. nuclear polyhedrosis virus silkworm Bombyx mori

Silkworm strains resistant to Bombyx mori L. nuclear polyhedrosis virus were obtained through transgenic experiments. piggyBac transposon with an A3 promoter were randomly inserted into the silkworm, driving the enhanced green fluorescent protein (EGFP) reporter gene into the silkworm genome. Polymerase chain reaction results verified the insertion of the extraneous EGFP gene, and fluorescence microscopy showed that the EGFP was expressed in the midgut tissue. The morbidity ratio of the nuclear polyhedrosis decreased from 90% in the original silkworm strain to 66.7% in the transgenic silkworm strain. Compared with the resistance to the Bombyx mori L. nuclear polyhedrosis virus in the Qiufeng strain, which is commonly used in the production, there was an increase of 33 centesimal points in the transgenic silkworms. The antivirotic character in the Chunhua x Qiuyue strain, which was bred from a different transgenic family, was about 10 centesimal points higher than that in the Qiufeng x Baiyu, another crossbreed used in production. Our results indicated a good application value of the transposon-inserted mutation in the breeding of anti-BmNPV silkworm strain.