Mutations in Conserved Residues of the C. elegans microRNA Argonaute ALG-1 Identify Separable Functions in ALG-1 miRISC Loading and Target Repression

microRNAs function in diverse developmental and physiological processes by regulating target gene expression at the post-transcriptional level. ALG-1 is one of two Caenorhabditis elegans Argonautes (ALG-1 and ALG-2) that together are essential for microRNA biogenesis and function. Here, we report the identification of novel antimorphic (anti) alleles of ALG-1 as suppressors of lin-28(lf) precocious developmental phenotypes. The alg-1(anti) mutations broadly impair the function of many microRNAs and cause dosage-dependent phenotypes that are more severe than the complete loss of ALG-1. ALG-1(anti) mutant proteins are competent for promoting Dicer cleavage of microRNA precursors and for associating with and stabilizing microRNAs. However, our results suggest that ALG-1(anti) proteins may sequester microRNAs in immature and functionally deficient microRNA Induced Silencing Complexes (miRISCs), and hence compete with ALG-2 for access to functional microRNAs. Immunoprecipitation experiments show that ALG-1(anti) proteins display an increased association with Dicer and a decreased association with AIN-1/GW182. These findings suggest that alg-1(anti) mutations impair the ability of ALG-1 miRISC to execute a transition from Dicer-associated microRNA processing to AIN-1/GW182 associated effector function, and indicate an active role for ALG/Argonaute in mediating this transition

Cell-specific microarray profiling experiments reveal a comprehensive picture of gene expression in the C. elegans nervous system

A novel strategy for profiling Caenorhabditis elegans cells identifies transcripts highly enriched in either the embryonic or larval C. elegans nervous system, including 19 conserved transcripts of unknown function that are also expressed in the mammalian brain

Trimetazidine MR effects on heart remodeling in stable coronary heart disease patients

Aim. To study trimetazidine MR effects on left ventricular (LV) remodeling in stable coronary heart disease (CHD) patients with completely controlled effort angina and arterial hypertension (AH), who received combined treatment. Material and methods. In total, 114 individuals were examined: Group I – 65 healthy volunteers (mean age 31,38 years); Group II - 49 untreated CHD and AH patients (mean age 62,32 years). All participants underwent transthoracic echocardiography, with calculation of systolic and diastolic spherical index, remodeling index (RI), systolic and diastolic myocardial stress (MSs, MSd), LV myocardial mass index, LV relative wall thickness (RWT). Results. After three months of combined, four-component treatment, clinical stabilization was not associated with significant changes in LV remodeling, only MSs reduced significantly after adding Preductal MV to the treatment. In stable good clinical status, no obvious clinical dynamics, and unchanged ejection fraction, structural and functional cardiac parameters improved substantially, with reduction (р<0,00001) in MSs (145,68±11,35 and 124,51±7,89); MSd (160,72±16,78 and 156,24±12,11), end-diastolic pressure (14,81±3,16 and 11,9±1,91 mm Hg), end-diastolic LV wall strain (1967,33±337,27 and 1519,99±224,74 dyne/cm2), as well as with increase in RI (93,72±8,48 and 100,87±9,74). LV diastolic function parameters improved, NYHA functional class reduced. Conclusion. Trimetazidine MR beneficial effects on myocardial elasticity, contractility, and remodeling were demonstrated. The medication can be used as an anti-remodeling agent in combined CHD treatment

Polypyrrole-palladium nanoparticles composite as efficient catalyst for Suzuki-Miyaura coupling

International audienceSynthesis of a new hybrid material (Pd/PPy) composed of polypyrrole globules with uniformly incorporated Pd nanoparticles via direct redox reaction between pyrrole and Pd(NH3)(4)Cl-2 in water has been recently reported (V.A. Zinovyeva, M.A.Vorotyntsev, I. Bezverkhyy, D. Chaumont, J.-C. Hierso, Adv. Funct. Mater. 21 (2011) 1064-1075). In the actual study, this procedure has been extended to synthesize a series of Pd/PPy powders with variable palladium content and morphological parameters. Depending on the monomer-to-oxidant ratio in reaction mixture, average diameters of Pd and PPy particles may change in the ranges of 1.25-1.45 and 27-62 nm, respectively, the Pd concentration being within 33.5-42.0 wt.%. In general terms, decrease of the monomer-to-oxidant ratio led to formation of the Pd/PPy hybrid material with smaller diameters of both components and a higher Pd loading. The Pd/PPy composites have been studied in Suzuki-Miyaura coupling and showed high catalytic efficiency. Aryl iodides, bromides and chlorides are active. The reaction can be performed using arylboronic acids or tetraarylborates, both in organic solvents and in water, thus making the process ecologically friendly. The recycling of the catalyst is possible if its particles are immobilized on the graphite support. The comparison of two samples revealed that Pd/PPy nanocomposite with the diameter of PPy spheres of about 30 nm is more efficient in catalysis, as compared to the sample with bigger PPy spheres (about 60 nm), due to transport limitations for reagents inside the polypyrrole sphere in the latter case. For palladium/polypyrrole nanocomposites with the small diameter of PPy sphere, which are easily penetrable for the reagents and in which all Pd nanoparticles are active. Pd content in polypyrrole spheres does not influence the yield of biaryls: the more is the Pd content in polypyrrole spheres, the less amount of catalyst is necessary to obtain the same yield of biaryl

Alterations in gene expression of proprotein convertases in human lung cancer have a limited number of scenarios.

Proprotein convertases (PCs) is a protein family which includes nine highly specific subtilisin-like serine endopeptidases in mammals. The system of PCs is involved in carcinogenesis and levels of PC mRNAs alter in cancer, which suggests expression status of PCs as a possible marker for cancer typing and prognosis. The goal of this work was to assess the information value of expression profiling of PC genes. Quantitative polymerase chain reaction was used for the first time to analyze mRNA levels of all PC genes as well as matrix metalloproteinase genes MMP2 and MMP14, which are substrates of PCs, in 30 matched pairs of samples of human lung cancer tumor and adjacent tissues without pathology. Significant changes in the expression of PCs have been revealed in tumor tissues: increased FURIN mRNA level (p<0.00005) and decreased mRNA levels of PCSK2 (p<0.007), PCSK5 (p<0.0002), PCSK7 (p<0.002), PCSK9 (p<0.00008), and MBTPS1 (p<0.00004) as well as a tendency to increase in the level of PCSK1 mRNA. Four distinct groups of samples have been identified by cluster analysis of the expression patterns of PC genes in tumor vs. normal tissue. Three of these groups covering 80% of samples feature a strong elevation in the expression of a single gene in cancer: FURIN, PCSK1, or PCSK6. Thus, the changes in the expression of PC genes have a limited number of scenarios, which may reflect different pathways of tumor development and cryptic features of tumors. This finding allows to consider the mRNAs of PC genes as potentially important tumor markers

Myofascial pain syndrome in female patients with chronic nonspecific back pain: diagnosis and treatment

Objective: to elucidate the frequency and pathogenesis of myofascial pain syndrome (MFPS) in chronic nonspecific lower back pain (CNLBP) and to optimize the diagnosis and treatment of MFPS in CNLBP.Patients and methods. The investigation covered 121 patients with CNLBP. The patients' mean age was 42.1±10.5 years; the pain duration was 7.9±4.3 months. The possible causes of CNLBP were determined: these were facet joints (FJs); sacroiliac joints (SIJs); skeletal muscles with the development of MFPS; MFPS concurrent with FJs; MFPS concurrent with SIJs. Twenty patients had MFPS only (its mean duration was 5.3±2.2 months; the mean pain intensity scores were 6.5±1.1 on a numerical rating scale). Six patients underwent examinations of open biopsy specimens of the muscle straightening the spinal column; a comparison group consisted of 3 healthy women matched for age and gender. The patients were prescribed therapy with aceclofenac 200 mg/day in combination with tolperisone 450 mg/day and nondrug therapy (cognitive behavioral therapy and kinesio- and ergotherapy). When the treatment was insufficiently effective, ultrasonography of the muscle straightening the spinal column was additionally performed; a local anesthetic was injected into myofascial trigger points (MTPs).Results and discussion. MFPS was a cause of pain syndrome in 63 (52%) patients, while MFPS this was an isolated cause of pain in 20 (16.5%) cases and was concurrent with FJ osteoarthritis in 23 (19%), and with SIJ dysfunction in 20 (16.5%). Muscle ultrasonography in patients with MFPS revealed MTPs, whereas examinations of biopsy specimens of the muscle straightening the spinal column showed no evidence of necrosis, fibrosis, or inflammatory infiltration in the presence of transformation of the myosin phenotype, by increasing the proportion of rapidly fatigued type II muscle fibers. The results of sodium dodecyl sulfate (SDS) gel electrophoresis indicated a decrease in the content of titin and nebulin, the sarcomeric cytoskeletal proteins involved in maintaining muscle contractility. A two-week cycle of therapy with aceclofenac and tolperisone reversed pain syndrome in 5 (25%) of the 20 patients and reduced the intensity of back pain in 15 (75%), but the pain increased during physical exercise and impeded active rehabilitation. The additional administration of anesthetics into MTPs and the continuous intake of aceclofenac and tolperisone in combination with kinesiotherapy could relieve pain syndrome and enhance motor activity.Conclusion. More than half of the patients with CNLBP had MFPS only or concurrent with joint pathology (FS and FJs). The changes found in the back muscle biopsy specimens of patients with CNLBP are potentially reversible and can be reversed during kinesiotherapy

Description of the specimens studied and heat map presentation of the ratio values of gene expression in tumor vs. adjacent tissues without histological pathology.

<p>SCC, squamous cell lung carcinoma; AdC, adenocarcinoma; AdC/SCC, both AdC and SCC cells were found in the tumor tissue; SCLC, small cell lung carcinoma; P, peripheral tumor location; C, central tumor location; Y, tumor with keratinization; N, tumor without keratinization; ‘-’, no data. The heat map is shown in log₂ scale. Gray cells indicate specimens with undetectable mRNA in both tumor and normal tissues.</p

Gene designations and TaqMan Gene Expression Assays used in real-time PCR.

*<p>HGNC – HUGO Gene Nomenclature Committee (<a href="http://www.genenames.org" target="_blank">www.genenames.org</a>).</p

Correlations between expression profiles of the genes studied.

*<p>R_s is Spearman correlation coefficient (p<0.05).</p