MiR-135a functions as a selective killer of malignant glioma

Glioma is the most common and fatal primary brain tumor. Thus far, therapeutic strategies to efficiently and specifically antagonize glioma are limited and poorly developed. Here we report that glia-enriched miR-135a, a microRNA that is dramatically downregulated in malignant glioma and correlated with the pathological grading, is capable of inducing mitochondria-dependent apoptosis of malignant glioma by regulating various genes including STAT6, SMAD5 and BMPR2, as well as affecting the signaling pathway downstream. Moreover, this lethal effect is selectively towards malignant glioma cells, but not neurons and glial cells, through a novel mechanism. Our findings suggest an important role of miR-135a in glioma etiology and provide a potential candidate for malignant glioma therapy.

Potential drug targets on insomnia and intervention effects of Jujuboside A through metabolic pathway analysis as revealed by UPLC/ESI-SYNAPT-HDMS coupled with pattern recognition approach

Potential metabolites from the metabolic pathways could be therapeutic targets and useful for the discovery of broad spectrum drugs. UPLC/ESI-SYNAPT-HDMS coupled with pattern recognition methods including PCA, PLS-DA, OPLS-DA and Heatmap were integrated to examine the global metabolic signature of insomnia and intervention effects of Jujuboside A (JuA). Six unique pathways of the insomnia were identified using Ingenuity Pathway Analysis (IPA) software. The VIP-value threshold cutoff of the metabolites was set to 10, above this threshold, were filtered out as potential target biomarkers. Sixteen distinct metabolites were identified from these pathways, and 6 of them can be considered for rational drug design. It was further experimental validation that the changes in metabolic profiling were restored to their baseline values after JuA treatment according to the multivariate data analysis. Potential metabolite network of the insomnia was preliminarily predicted JuA-target interaction networks, and could be further explored for in silico docking studies with suitable drugs. Thus, our method is an efficient procedure for drug target identification through metabolic analysis. It can guide testable predictions, provide insights into drug action mechanisms and enable us to increase research productivity toward metabolomic drug discovery.

Rapid and global detection and characterization of the constituents in ShengMai San by ultra-performance liquid chromatography-high-definition mass spectrometry

An ultra-performance liquid chromatography-high definition mass spectrometry (UPLC-HDMS) method was developed for detection and characterization of the chemical constituents in ShengMai San (SMS), a traditional Chinese medical formula (TCMF). The full-scan LC-MS/MS data sets combined with extra mass were acquired within 14 min using UPLC-HDMS in the MS(E) mode in a single injection. As a result, 92 compounds were identified by comparing the accurate mass and fragments information with that of the authentic standards as well as by MS analysis and the correlative references data. These constituents included ginsenosides, lignans, steroidal saponins and homoisoflavanones. Among them, 25-hydroxyginsenosides were discovered in SMS for the first time. Compare with the previous studies, our research detected more compounds and presented more rapid by applying UPLC-HDMS. It is concluded that a rapid and effective method has been established based on UPLC-HDMS with the utilization of MS(E) , which shows high sensitivity and resolution that is suitable for identifying the constituents of SMS, and this method could be applied to other TCMF.

Metabolomic study of insomnia and intervention effects of Suanzaoren decoction using ultra-performance liquid-chromatography/electrospray-ionization synapt high-definition mass spectrometry

Metabolomics is the comprehensive assessment of endogenous metabolites of a biological system in a holistic context, and its property consists with the global view of traditional Chinese medicine (TCM). Suanzaoren decoction (SZRD), an ancient TCM formulae, has been used for treating insomnia for centuries, and its mechanism remains unclear completely. This paper was designed to explore globally metabolomic characters of the insomnia and the therapeutic effects of SZRD. Ultra-performance liquid-chromatography/electrospray-ionization synapt high-definition mass spectrometry (UPLC/ESI-SYNAPT-HDMS) combined with pattern recognition approaches including principal component analysis (PCA), partial least squares-discriminant analysis (PLS-DA) and orthogonal projection to latent structures discriminate analysis (OPLS-DA) were integrated to approximate the comprehensive metabolic signature and discover differentiating metabolites. The changes in metabolic profiling were restored to their baseline values after SZRD treatment according to the PCA score plots. Altogether, the current metabonomic approach based on UPLC/ESI-SYNAPT-HDMS indicate 20 ions (9 in the negative mode, 11 in the positive mode) as "differentiating metabolites". The alterations in these metabolites were associated with perturbations in amino acid and fatty acid metabolism, in response to insomnia through immune and nervous system. Of note, we found that SZRD increases sleep activity and exhibits binding affinity for serotonin receptors. These results implicate the therapeutic effects of SZRD may mediate through serotonergic activation. Our findings also show the robust UPLC/ESI-SYNAPT-HDMS techniques is promising for metabolites profiling analysis of TCM and open new perspectives to using metabolomics platform to resolve special TCM issues.

The clinical values of methylation status of P16 and APC genes in bile in diagnosis of malignant obstructive jaundice

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Background: Preoperative definitive diagnosis of malignant obstructive jaundice caused by biliary and pancreatic carcinomas still remains a major challenge. Hypermethylation of tumor suppressor genes have been implied in carcinogenesis of biliary and pancreatic malignancies. The diagnostic values of methylation status of tumor suppressor genes in bile in malignant obstructive jaundice have not been well-documented.

Methods: Bile was prospectively collected from 70 patients with obstructive jaundice treated at our hospital between November 2008 and Sepetember 2009. Forty-eight of them were proved to be malignant obstructive jaundice (biliary carcinoma in 36, pancreatic carcinoma in 8 and duodenal carcinoma in 4) by pathological examination, and 22 were benign obstructive jaundice caused by cholelithiasis. DNA was extracted from bile and modified by sodium bisulfite. Methylation-specific PCR was run to detect methylation status of P16 and APC gene promoters. Their diagnostic values in malignant obstructive jaundice were assessed.

Results: Hypermethylation of P16 promoter was presented in 72.9% (35/48) malignant obstructive jaundice, and 9% (2/22) bengin obstructive jaundice (p<0.05). Hypermethylation of APC promoter was presented in 56.2% (27/48) malignant obstructive jaundice, and 9% (2/22) bengin obstructive jaundice (p<0.05). With respect to their diagnostic values in malignant obstructive jaundice, sensitivity, specificity, positive predictivity and negative predictivity were 72.9%, 90.9%, 94.6% and 60.6%, respectively, for P16 gene; 56.2%, 90.9%, 93.1%, 48.8%, respectively, for APC gene.

Conclusions: Methylation status of P16 and APC gene promoters in bile was valuable in diagnosis of malignant obstructive jaundice, with an excellent specificity. P16 gene had a higher sensitivity than APC gene.

No significant financial relationships to disclose.

First Report of Bituminaria Witches'-Broom in Australia Caused by a 16SrII Phytoplasma

Bituminaria bituminosa (L.) Stirt. is a perennial legume known as Arabian pea that is used as a forage in arid areas and for stabilization of degraded soils. It is widely distributed in the Mediterranean Basin with wider adaptation across the Canary Islands (4). In July 2010, during a survey for phytoplasma, some Canary Island B. bituminosa plants with typical phytoplasma symptoms, including stunted growth with small leaves, shortened internodes, and bushy growth, were found in seed multiplication nurseries at Medina, Perth, Western Australia (115°48.5'E; 32°13.2'S). Two samples from plants with clear disease symptoms and two visibly healthy plants were collected and total DNA was extracted with the Illustra DNA extraction kit Phytopure (GE Healthcare) according to the manufacturer's instructions. Direct and nested PCR were used to test the presence of phytoplasma 16S rDNA in samples with universal primers P1/P7 and R16F2n/R16R2, respectively (1,3). The PCR amplifications from all diseased samples yielded an expected product of 1.8 kb by direct and 1.2 kb by nested PCR, but not from the healthy plant samples. The direct PCR product was used as a template DNA in sequencing and the DNA sequence was deposited in the NCBI GenBank (Accession No. HQ404357). Sequence homology analysis indicated there was a perfect match between the two isolates. BLAST search of the NCBI GenBank revealed that B. bituminosa phytoplasma shares >99% sequence identity with Crotalaria witches'-broom phytoplasma (Accession No. EU650181.1), pear decline phytoplasma (Accession No. EF656453.1), and Scaevola witches'-broom phytoplasma (Accession No. AB257291.1). On the basis of BLAST analyses of 16S rRNA gene sequences, B. bituminosa phytoplasma in Western Australia appears to belong to the peanut witches'-broom group (16SrII-D) of phytoplasma. Restriction fragment length polymorphism analysis was also performed on nested PCR products of two samples of B. bituminosa phytoplasma by separate digestion with HaeIII, Hind6I, HpaII, MboI, RsaI, Tru9I, and T-HB8I restriction enzymes. Samples yielded patterns similar to alfalfa witches'-broom phytoplasma (Accession No. AF438413) belonging to subgroup 16SrII-D (2). To our knowledge, this is the first report of a phytoplasma of the 16SrII-D group infecting B. bituminosa in Australia and should be referred to as "Bituminaria witches'-broom phytoplasma" (BiWB). This report also indicates that the occurrence of the phytoplasma in B. bituminosa may be widespread in the Canary Islands and other species of Bituminaria might be susceptible to infection by Bituminaria witches'-broom phytoplasma. References: (1) D. E. Gundersen and I.-M. Lee. Phytopathol. Mediterr. 35:144, 1996. (2) A. J. Khan et al. Phytopathology 92:1038, 2002. (3) I.-M. Lee et al. Int. J. Syst. Evol. Microbiol. 54:337, 2004. (4) P. Mendez et al. Grassland Sci. Eur. 11:300, 2006.

BP neural network classification for bleeding detection in wireless capsule endoscopy

Bleeding in the digestive tract is one of the most common gastrointestinal tract (GI) diseases, as well as the complication of some fatal diseases. Wireless capsule endoscopy (WCE) allows physicians to noninvasively examine the entire GI tract. However it is very laborious and time-consuming to inspect large numbers of WCE images, which limits the wider application of WCE. It is therefore important to develop an automatic and intelligent computer-aided bleeding detection technique. In this paper, a new method aimed at bleeding detection in WCE images is proposed. Colour texture features distinguishing the bleeding regions from non-bleeding regions are extracted in RGB and HSI colour spaces; then a neural network using the colour texture features as the feature vector inputs is designed to recognize the bleeding regions. The experiments demonstrate that the bleeding regions can be correctly recognized and clearly marked out. The sensitivity of the algorithm is 93% and the specificity is 96%.

A micro creeping robot for colonoscopy based on the earthworm

Minimally Invasive Surgery (MIS) has become one of the most important research areas in the field of medical engineering. Robotic colonoscopy is a typical medical procedure that complies with the requirements of MIS. In this paper, a new novel miniature robot for intestinal inspection based on the earthworm is described; its diameter and length are 7.5 mm and 120 mm respectively. The micro robot is driven by a DC motor which has good performance and sufficient power. In this paper the structure and locomotion mechanism of this robot are introduced; the mechanical model is built; and simulation is carried out. The control system and software design are also discussed in detail. Some actuating characteristic experiments have been performed, where the micro robot creeps in declining rubber tubes. The experimental results are in accord with simulation results, and show that this kind of robot can move reliably in horizontal and certain declining tubes. This research has laid a foundation for the application of the miniature robot endoscope.