2′-OMe-phosphorodithioate-modified siRNAs show increased loading into the RISC complex and enhanced anti-tumour activity

Improving small interfering RNA (siRNA) efficacy in target cell populations remains a challenge to its clinical implementation. Here, we report a chemical modification, consisting of phosphorodithioate (PS2) and 2′-O-Methyl (2′-OMe) MePS2 on one nucleotide that significantly enhances potency and resistance to degradation for various siRNAs. We find enhanced potency stems from an unforeseen increase in siRNA loading to the RNA-induced silencing complex, likely due to the unique interaction mediated by 2′-OMe and PS2. We demonstrate the therapeutic utility of MePS2 siRNAs in chemoresistant ovarian cancer mouse models via targeting GRAM domain containing 1B (GRAMD1B), a protein involved in chemoresistance. GRAMD1B silencing is achieved in tumours following MePS2-modified siRNA treatment, leading to a synergistic anti-tumour effect in combination with paclitaxel. Given the previously limited success in enhancing siRNA potency with chemically modified siRNAs, our findings represent an important advance in siRNA design with the potential for application in numerous cancer types

Protective effects of N-acetylcysteine on acetic acid-induced colitis in a porcine model

BACKGROUND: Ulcerative colitis is a chronic inflammatory disease and involves multiple etiological factors. Acetic acid (AA)-induced colitis is a reproducible and simple model, sharing many characteristics with human colitis. N-acetylcysteine (NAC) has been widely used as an antioxidant in vivo and in vitro. NAC can affect several signaling pathways involving in apoptosis, angiogenesis, cell growth and arrest, redox-regulated gene expression, and inflammatory response. Therefore, NAC may not only protect against the direct injurious effects of oxidants, but also beneficially alter inflammatory events in colitis. This study was conducted to investigate whether NAC could alleviate the AA-induced colitis in a porcine model. METHODS: Weaned piglets were used to investigate the effects of NAC on AA-induced colitis. Severity of colitis was evaluated by colon histomorphology measurements, histopathology scores, tissue myeloperoxidase activity, as well as concentrations of malondialdehyde and pro-inflammatory mediators in the plasma and colon. The protective role of NAC was assessed by measurements of antioxidant status, growth modulator, cell apoptosis, and tight junction proteins. Abundances of caspase-3 and claudin-1 proteins in colonic mucosae were determined by the Western blot method. Epidermal growth factor receptor, amphiregulin, tumor necrosis factor-alpha (TNF-α), and toll-like receptor 4 (TLR4) mRNA levels in colonic mucosae were quantified using the real-time fluorescent quantitative PCR. RESULTS: Compared with the control group, AA treatment increased (P < 0.05) the histopathology scores, intraepithelial lymphocyte (IEL) numbers and density in the colon, myeloperoxidase activity, the concentrations of malondialdehyde and pro-inflammatory mediators in the plasma and colon, while reducing (P < 0.05) goblet cell numbers and the protein/DNA ratio in the colonic mucosa. These adverse effects of AA were partially ameliorated (P < 0.05) by dietary supplementation with NAC. In addition, NAC prevented the AA-induced increase in caspase-3 protein, while stimulating claudin-1 protein expression in the colonic mucosa. Moreover, NAC enhanced mRNA levels for epidermal growth factor and amphiregulin in the colonic mucosa. CONCLUSION: Dietary supplementation with NAC can alleviate AA-induced colitis in a porcine model through regulating anti-oxidative responses, cell apoptosis, and EGF gene expression

Exome Sequencing for cerebral palsies: Opening windows for differential diagnosis

DNA sequencing technologies played a critical role in the last two decades in expanding our understanding of genetic spectrum behind neurodevelopmental disorders. Recently, induction MPS in the area of medical genetics provided chance for differential diagnosis and/or reverse phenotyping of cerebral palsies and many other developmental disorders. Here we present how ES through MPS has identified causative mutations and showed scope for further characterization of the neurodevelopmental disorders. Here we report and discuss four cases (5Y to 12Y) who were diagnosed as CP with mild or moderate ID. Whole Exome libraries were constructed using Exome RDY panel and sequenced on Ion Proton. The reads generated were aligned to hg19 and variants were annotated and prioritized using Ion Reporter. In Cases-I &amp; II a homozygous mutation in PMM2 gene (NM_000303.2, c.710C&gt;T, p.THR237ARG) and a novel nonsense mutation in gene SLC35A2 (NM_005660.2, c.1024C&gt;T, p.Arg342Ter) which are known to cause congenital disorder of glycosylation type Ia (MIM: 212065) and type IIm SOMATIC MOSAIC (MIM: 300896) were identified, respectively. In case-III (two male siblings) ES identified a novel Frame Shift (FS) mutation in APRATAXIN (APTX) gene (NM_001195248.1, c.638delG, p.Arg213fs, rs150886026) which are known to cause ATAXIA-OCULOMOTOR APRAXIA 1; AOA1 (MIM: 208920). Brain imaging in Case-IV is suggestive of Joubert syndrome with hearing loss, we identified a missense mutation in AHI1 gene (NM_001134830.1, c.2023G&gt;A, p.Asp675Asn) and also a nonsense mutation in gene GJB2 (NM_004004.5, c.71G&gt;A, p.Trp24Ter) which explains the hearing impairment in the case. Mutations in cases and parent(s) were confirmed on 3500 Genetic Analyzer revealed Autosomal recessive or X-linked dominant and somatic mosaicism pattern of inheritance. Reverse phenotyping was convincing for Case I &amp; II.  Case III phenotype was delineated by the identification of responsible gene /mutation.  Complex phenotype of Case IV was characterized as revealed by genotyping.  Our work suggests genotype first approach will be beneficial for prompt &amp; precise diagnosis and reverse phenotyping of neurodevelopmental disorders

Whole exome sequencing identifies a novel homozygous frameshift mutation in the ASPM gene, which causes microcephaly 5, primary, autosomal recessive [version 1; referees: 2 approved]

Microcephaly is a genetically heterogeneous disorder and is one of the frequently notable conditions in paediatric neuropathology which exists either as a single entity or in association with other co-morbidities. More than a single gene is implicated in true microcephaly and the list is growing with the recent advancements in sequencing technologies. Using massive parallel sequencing, we identified a novel frame shift insertion in the abnormal spindle-like microcephaly-associated protein gene in a client with true autosomal recessive primary microcephaly.  Exome sequencing in the present case helped in identifying the true cause behind the disease, which helps in the premarital counselling for the sibling to avoid future recurrence of the disorder in the family

Damage Classification for Structural Health Monitoring Using Time-Frequency Feature Extraction and Continuous Hidden Markov Models

Abstract—We propose an algorithm for the classification of structural damage based on the use of the continuous hidden Markov modeling (HMM) technique. Our approach employs HMMs to model time-frequency damage features extracted from structural data using the matching pursuit decomposition algorithm. We investigate modeling with continuous observation-density HMMs and discuss the trade-offs involved as compared to the discrete HMM case. A variational Bayesian method is employed to automatically estimate the HMM state number and adapt the classifier for real-time use. We present results that classify structural and material (fatigue) damage in a bolted-joint structure. I

Genetic association of G896A polymorphism of TLR4 gene in leprosy through family-based and case-control study designs

Background: Polymorphisms in TLR4 may change the function of the protein and alter the efficiency of immune response of host to infection. The high relevance of host gene polymorphisms with outcome of Mycobacterium leprae infection led us to study the genetic association of TLR4 G896A polymorphism in order to identify its risk among contacts of affected leprosy patients. Methods: For case-control study design a total of 628 individuals were recruited; 17 multicase leprosy families which included 32 case-parent trios were considered for family-based study. Genotyping was done using PCR-RFLP method. Results: In case-control study AA genotype was positively associated while GA genotype was negatively associated with leprosy. In family based transmission disequilibrium test (TDT) analysis allele G was found to be over transmitted to the affected individuals. Conclusion: Case-control study suggests that homozygous AA genotype may confer susceptibility and heterozygous GA genotype may confer resistance to leprosy, while allele A was observed to increase risk and that of allele G may confer resistance to leprosy. No strong transmission disequilibrium was detected in family-based TDT analysis, possibly due to lower number of trios. In contrast to case-control data allele G was over transmitted to the affected ones in TDT analysis. To conclude, the frequencies of genotypes in household contacts were almost the same as in leprosy patients, suggesting that contacts with AA genotype may be at higher risk of leprosy and may therefore require prophylactic inputs