Rapid and visual detection of human enterovirus coxsackievirus A16 by reverse transcription loop-mediated isothermal amplification combined with lateral flow device

In this study, a reverse transcription loop-mediated isothermal amplification (RT-LAMP) combined with lateral flow device (LFD) technology to rapidly detect CVA16 was developed and evaluated. RT-LAMP assay was optimized to amplify VP1 gene of CVA16. Amplified products were analysed by LFD and capillary electrophoresis. The RT-LAMP-LFD assay showed 100% specificity in detecting CVA16, and showed analytical sensitivity of 0·55 TCID50 per reaction mixture. Comparison of the RT-LAMP-LFD assay with real-time RT-PCR developed previously in clinical specimens showed 93·3% agreement. The RT-LAMP-LFD assay is more sensitive in detecting CVA16 RNA. The RT-LAMP-LFD assay presented here might offer a rapid and simple alternative in clinical diagnosis of CVA16.

SIGNIFICANCE AND IMPACT OF THE STUDY

Coxsackievirus A16 (CVA16) is one of the major causative agents of hand, foot and mouth disease (HFMD). Rapid and reliable detection and typing of it can limit the spread. We developed a reverse transcription loop-mediated isothermal amplification (RT-LAMP) combined with lateral flow device (LFD) technology to rapidly detect CVA16. The high sensitivity and specificity and its ease of use make this assay ideal for use in resource-limited settings such as primary care facilities and clinical laboratories in developing countries.

Long non-coding RNA MEG3 suppresses migration and invasion of thyroid carcinoma by targeting of Rac1

Thyroid cancer, the most common primary endocrine malignancy in adult, imperatively requires new therapeutic studies that could target the molecular regulatory mechanism. Even though emerging evidence showed that long noncoding RNAs (Lnc-RNAs) are involved in different biological characteristic of malignant tumor, such as cell growth and apoptosis as well as cancer progression and metastasis. Limited data are available on the function of Lnc-RNAs in thyroid cancer invasion and metastasis. Among the 5 tested lnc-RNAs , the present study demonstrates that MEG3 was significantly down-regulated in papillary thyroid carcinoma (PTC) tissues with lymph-node metastasis than in primary thyroid cancer. Moreover, the down- regulated MEG3 was associated with lymph-node metastasis. Over-expression of MEG3 could strongly inhibit the cell migration and invasion in TPC-1 and HTH83 thyroid cancer cell lines. In addition, we also showed that Rac1 was negatively regulated by lncRNA-MEG3 at the posttranscriptional level, via a specific target site within the 3΄UTR by dual luciferase reporter assay. The expression of Rac1 was inversely correlated with lncRNA-MEG3 expression in PTC tissues. Thus, this study suggests that MEG3 acts as novel suppressor of migration and invasion by targeting Rac1 gene.

A myostatin and activin decoy receptor enhances bone formation in mice

Myostatin is a member of the bone morphogenetic protein/transforming growth factor-β (BMP/TGFβ) super-family of secreted differentiation factors. Myostatin is a negative regulator of muscle mass as shown by increased muscle mass in myostatin deficient mice. Interestingly, these mice also exhibit increased bone mass suggesting that myostatin may also play a role in regulating bone mass. To investigate the role of myostatin in bone, young adult mice were administered with either a myostatin neutralizing antibody (Mstn-mAb), a soluble myostatin decoy receptor (ActRIIB-Fc) or vehicle. While both myostatin inhibitors increased muscle mass, only ActRIIB-Fc increased bone mass. Bone volume fraction (BV/TV), as determined by microCT, was increased by 132% and 27% in the distal femur and lumbar vertebrae, respectively. Histological evaluation demonstrated that increased BV/TV in both locations was attributed to increased trabecular thickness, trabecular number and bone formation rate. Increased BV/TV resulted in enhanced vertebral maximum compressive force compared to untreated animals. The fact that ActRIIB-Fc, but not Mstn-mAb, increased bone volume suggested that this soluble decoy receptor may be binding a ligand other than myostatin, that plays a role in regulating bone mass. This was confirmed by the significant increase in BV/TV in myostatin deficient mice treated with ActRIIB-Fc. Of the other known ActRIIB-Fc ligands, BMP3 has been identified as a negative regulator of bone mass. However, BMP3 deficient mice treated with ActRIIB-Fc showed similar increases in BV/TV as wild type (WT) littermates treated with ActRIIB-Fc. This result suggests that BMP3 neutralization is not the mechanism responsible for increased bone mass. The results of this study demonstrate that ActRIIB-Fc increases both muscle and bone mass in mice. Therefore, a therapeutic that has this dual activity represents a potential approach for the treatment of frailty.

Feedback control of TET system with variable coupling coefficients for a novel artificial anal sphincter

For treating severe faecal incontinence, the authors developed an intelligent artificial anal sphincter system (AASS) equipped with a feedback sensor that utilized a transcutaneous energy transfer system (TETS). To deliver the correct amount of power (i.e. to match the load demand under variable coupling conditions caused by changes in positioning between the coils due to fitting and changes in posture), a regulating method to stabilize output voltage with a closed loop variable-frequency controller was developed in this paper. The method via which the voltage gain characteristics of a voltage-fed series-tuned TETS were derived is also described. The theoretical analysis was verified by the results of the experiment. A numerical analysis method was used as a control rule with respect to the relationship between operating frequency and output voltage. To validate the feedback control rules, a prototype of the TET charging system was constructed, and its performance was validated with the coupling variation between 0.12-0.42. The results show that the output voltage of the secondary side can be maintained at a constant 7 V across the whole coupling coefficient range, with a switching frequency regulation range of 271.4-320.5 kHz, and the proposed controller has reached a maximal end-to-end power efficiency of 67.5% at 1 W.

Identification of genome regions controlling cotyledon, pod wall/seed coat and pod wall resistance to pea weevil through QTL mapping

Pea weevil, Bruchus pisorum, is one of the limiting factors for field pea (Pisum sativum) cultivation in the world with pesticide application the only available method for its control. Resistance to pea weevil has been found in an accession of Pisum fulvum but transfer of this resistance to cultivated pea (P. sativum) is limited due to a lack of easy-to-use techniques for screening interspecific breeding populations. To address this problem, an interspecific population was created from a cross between cultivated field pea and P. fulvum (resistance source). Quantitative trait locus (QTL) mapping was performed to discover the regions associated with resistance to cotyledon, pod wall/seed coat and pod wall resistance. Three major QTLs, located on linkage groups LG2, LG4 and LG5 were found for cotyledon resistance explaining approximately 80 % of the phenotypic variation. Two major QTLs were found for pod wall/seed coat resistance on LG2 and LG5 explaining approximately 70 % of the phenotypic variation. Co-linearity of QTLs for cotyledon and pod wall/seed coat resistance suggested that the mechanism of resistance for these two traits might act through the same pathways. Only one QTL was found for pod wall resistance on LG7 explaining approximately 9 % of the phenotypic variation. This is the first report on the development of QTL markers to probe Pisum germplasm for pea weevil resistance genes. These flanking markers will be useful in accelerating the process of screening when breeding for pea weevil resistance.

Gut content identification of larvae of the Anopheles gambiae complex in western Kenya using a barcoding approach

Although larvae feeding and food source are vital to the development, survival and population regulation of African malaria vectors, the prey organisms of Anopheles gambiae larvae in the natural environment have not been well studied. This study used a molecular barcoding approach to investigate the natural diets of Anopheles gambiae s.l. larvae in western Kenya. Gut contents from third- and fourth-instar larvae from natural habitats were dissected and DNA was extracted. The 18S ribosomal DNA gene was amplified, the resulting clones were screened using a restriction fragment length polymorphism method and nonmosquito clones were sequenced. Homology search and phylogenetic analyses were then conducted using the sequences of non-mosquito clones to identify the putative microorganisms ingested. The phylogenetic analyses clustered ingested microorganisms in four clades, including two clades of green algae (Chlorophyta, Chlorophyceae Class, Chlamydomonadales and Chlorococcales families), one fungal clade, and one unknown eukaryote clade. In parallel, using the same approach, an analysis of the biodiversity present in the larval habitats was carried out. This present study demonstrated the feasibility of the barcoding approach to infer the natural diets of Anopheles gambiae larvae. Our analysis suggests that despite the wide range of microorganisms available in natural habitats, mosquito larvae fed on specific groups of algae. The novel tools developed from this study can be used to improve our understanding of the larval ecology of African malaria vectors and to facilitate the development of new mosquito control tools.