Site-specific conjugation of drug-like fragments to an antimiR scaffold as a strategy to target miRNAs inside RISC.

We synthesized a miR-122 antimiR library in which drug-like fragments were site-specifically introduced to short 2'-O-methyl-RNAs. At some sites selected fragments elevated cellular antimiR activity to that of an unmodified 23mer antimiR, whereas at others the same fragments abolished activity. The potency of the antimiRs correlated with uptake into miRISC.

Anti-miRNA oligonucleotides (AMOs): ammunition to target miRNAs implicated in human disease?

MicroRNAs (miRNAs) are endogenous 19-25 nucleotide RNAs that have recently emerged as a novel class of important gene-regulatory molecules involved in many critical developmental and cellular functions. miRNAs have been implicated in the pathogenesis of several human diseases, such as neurodegenerative disorders, cancer, and more recently in viral and metabolic diseases. Unraveling the roles of miRNAs in cellular processes linked to human diseases will lead to novel opportunities for the regulation of protein function and will help to evaluate their potential for therapeutic intervention. Approaches to interfere with miRNA function in vitro and in vivo based on synthetic anti-miRNA oligonucleotides (AMOs) are discussed in this review.

Molecular phylogeny of Larrea and its allies (Zygophyllaceae): reticulate evolution and the probable time of creosote bush arrival to North America.

Nucleotide sequences of Rubisco Large Subunit (rbcL) and the internal transcribed spacers (ITS) of nrDNA were obtained for the five species of Larrea and one species each of Bulnesia (ITS only) and Plectrocarpa (rbcL only). Parsimony analyses were conducted, including sequences from seven genera of Zygophyllaceae reported by other authors-Kallstroemia, Zygophyllum, Augea, Fagonia, Pintoa, Guaiacum, and Porlieria. The main conclusions of the present study are (1) the Argentine endemic Plectrocarpa tetracantha belongs to the subfamily Larreoideae (New World Clade); (2) all three phylogenies obtained from rbcL, ITS, and combined data sets show a close relationship between the tetraploid L. cuneifolia (sect. Bifolium) and the diploid multifoliolate pair L. nitida-L. ameghinoi (sect. Larrea), which could result from a possible intersectional hybrid origin of the tetraploid; (3) L. divaricata (sect. Bifolium) and L. tridentata (sect. Bifolium) form a highly supported monophyletic group, which agrees with previous cytogenetic and molecular evidence; and (4) the rate of nucleotide substitution of rbcL was estimated based on geological and fossil records. Under the molecular clock hypothesis, nucleotide sequence divergence between L. divaricata and L. tridentata suggests a Late Neogene (8.4 to 4.2 mybp) time of arrival of the diploid ancestors of L. tridentata to North American deserts.

Correlates of physical activity in chronic obstructive pulmonary disease.

BACKGROUND: Physical activity is a key dimension of functional status in people with chronic obstructive pulmonary disease (COPD), and the central target of interventions in this group. OBJECTIVES: To determine the relationships among functional performance measured as physical activity, functional capacity, symptom experiences, and health-related quality of life in people with COPD. METHOD: Cross-sectional, descriptive study. Convenience sample of 63 outpatients with COPD studied prior to entry into a pulmonary rehabilitation program. RESULTS: Daily physical activity, as measured by an accelerometer, was strongly associated with maximal distance walked during a 6-minute walk test (r = .60, p < .00), level of airway obstruction (r = .37, p < .01), walking self-efficacy (r = .27, p < .05), and physical health status (r = .40, p < .01). Physical activity was not correlated with self-report of functional status. The only predictor of physical activity was the 6-minute walk test. CONCLUSIONS: Accelerometer measurement of functional performance was most significantly related to walking abilities. This methodology represents a novel approach to measuring an important dimension of functional status not previously well quantified.

Mandibular bone formation rates in aged ovariectomized rats treated with anti-resorptive agents alone and in combination with intermittent parathyroid hormone.

Anti-resorptive agents--including estrogen (E), calcitonin (CT), and bisphosphonates--are established in the treatment of osteoporosis. Intermittent administration of parathyroid hormone (PTH) stimulates bone formation and is a possible therapeutic agent for the restoration of bone mass. The purpose was to determine the effects of the anti-resorptive agents alone and in combination with intermittent PTH on bone formation in the mandible and a long bone in the aged ovariectomized (Ovx) rat. Female rats were ovariectomized or sham-operated. One year later, groups of Ovx rats were treated with E, CT, or the bisphosphonate, Risedronate (NE). Additional groups of Ovx rats were treated with each of these agents in combination with human PTH for 10 weeks. Estrogen treatment suppressed most indices of bone formation in the humerus and mandible, while NE decreased some indices of formation at the endocortical and endosteal surfaces of the mandible and humerus. Increased double-labeled surface and mineral apposition rates were observed only on the mandibular endosteal surfaces following CT treatment. When the anti-resorptive agents were combined with intermittent PTH, most indices of bone formation at all skeletal sites were substantially greater than those of the untreated Ovx controls as well as the E-, CT-, and NE-treated groups, respectively. These results provide additional evidence that established and emerging therapies for osteoporosis affect osseous tissues in the oral cavity, and this may influence the progression of diseases and/or aging changes at this site.

Synthesis of aminoglycoside-modified oligonucleotides.

[structure: see text] To study the structural requirements of aminoglycoside binding to nucleic acids, compound 1-an analogue of the naturally occurring nucleoside J-was synthesized. When incorporated into oligodeoxynucleotides, 1 leads to thermal stabilization of the resulting duplexes. The increase in pairing affinity is stronger with complementary RNA than with DNA.

Synthesis of 5-(2-amino-2-deoxy-beta-D-glucopyranosyloxymethyl)-2'- deoxyuridine and its incorporation into oligothymidylates.

The protected 5-(2-amino-2-deoxy-beta-D-glucopyranosyloxymethyl)-2'- deoxyuridine phosphoramidite 15 has been prepared from uridine in 12 steps. When incorporated into oligodeoxyribonucleotides the novel nucleoside analog 5 leads to decreased binding affinity. This decrease is larger with a complementary RNA-strand than with a DNA complement.

Isozyme variation in Larrea ameghinoi and Larrea nitida (Zygophyllaceae): genetic diversity and its bearing on their relationship.

Electrophoretic variants for 11 isozyme systems were examined by horizontal polyacrilamide gel electrophoresis in natural populations of Larrea ameghinoi and L. nitida (section Larrea). The two taxa presented fixed alternative allelic variants at loci Adh-1, Gdh-1 and Mdh-1. Genetic variability estimates showed no statistically significant differences among populations of section Larrea (He: 0.097-0.167). However, these values were significantly lower than those reported for species of section Bifolium (L. divaricata, diploid L. tridentata) in a previous contribution (He: 0.17-0.29). Positive and highly significant Wright's fixation indices are in agreement with higher amounts of inbreeding for L. nitida and L. ameghinoi, as suggested on the basis of floral morphology by previous authors. Moreover, the higher levels of genetic differentiation obtained for conspecific populations of section Larrea as compared to those of section Bifolium are also consistent with these observations. Nei's genetic identity values obtained for sympatric (I = 0.80) and allopatric (I = 0.63-0.73) L. ameghinoi - L. nitida population pairs are concordant with those expected for different, but closely related congeneric species.

2'-Deoxy-2'(S)-ethinyl oligonucleotides: a modification which selectively stabilizes oligoadenylate pairing to DNA complements.

Oligonucleotides consisting of 2'-deoxy-2'(S)-ethinyl-thymidine,-uridine, and -adenosine have been prepared. Whereas the modified pyrimidine oligonucleotides uniformly lead to weaker pairing affinity with DNA and RNA complements, the corresponding adenine oligonucleotides show enhanced thermal stability in duplexes with complementary DNA and decreased stability with RNA.

Intermittent parathyroid hormone administration stimulates bone formation in the mandibles of aged ovariectomized rats.

Intermittent administration of parathyroid hormone (PTH) is known to stimulate bone formation in many skeletal sites and is being investigated as a possible therapeutic agent for the treatment of osteopenic conditions, including post-menopausal osteoporosis. The purpose of this study was to determine the ability of PTH to stimulate bone formation in the mandibles of aged ovariectomized (Ovx) rats, and the results are compared with a site in the appendicular skeleton (humerus). The Ovx rat is a useful model of estrogen deficiency, replicating many aspects of post-menopausal osteoporosis. Female rats were ovariectomized or sham-operated, and one year later a group of the ovariectomized rats was treated with the 1-34 fragment of human PTH daily, five days a week for 10 weeks. During the experiment, the animals were given fluorochrome bone markers for histomorphometry. More than one year after ovariectomy or sham surgery, there were few differences in the histomorphometric indices of bone formation in the humerus or mandible. PTH treatment had no effect on dentin formation, measured in the mandibular incisor; however, most indices of bone formation-including the double-labeled surface, mineralizing surface, mineral appositional rate, new bone area, and surface-referent bone formation rates-were substantially greater in the PTH-treated group compared with both the Ovx and the Sham controls measured at the periosteal and endocortical surfaces of the humerus and the periosteal and cancellous bone surfaces of the mandible. In addition, bone formation at the alveolar crest, particularly on the buccal side, was greater in the PTH-treated group. The results from this study demonstrate that systemic intermittent PTH treatment stimulates bone formation in the mandibles in aged, estrogen-deficient animals.

Isozymes in Larrea divaricata and Larrea tridentata (Zygophyllaceae): a study of two amphitropical vicariants and autopolyploidy.

Electrophoretic variants for seven isozyme systems - probably encoded by 18 structural gene loci - in diploid populations of Larrea divaricata and diploid and tetraploid populations of its North American vicariant derivative L. tridentata were assayed by polyacrilamide and starch gel electrophoresis. High molecular similarity of diploid and tetraploid cytotypes of L. tridentata supports the hypothesis of interracial autopolyploidy. The absence of fixed heterozygosity and additive profiles indicates a low level of divergence between the parental diploids and the tetraploids. The phenogram based on the I coefficient showed the similarities between the populations of diploid L. divaricata and also between the diploid populations of L. tridentata. Both groups of diploid populations were more distantly connected to tetraploid L. tridentata.

Evaluation of a new rat feeder for use in chemical toxicology and nutrition studies.

A rat feeder was designed, fabricated, and evaluated which eliminated many of the problems associated with commercially available rat feeders (such as inadequate feed capacity, excessive feed spillage, excessive feed contamination, and difficulties with cleaning feeders). The feeder was capable of holding up to 700 g of meal-type feed. It provided rats with a continuous supply of diet which was virtually free from feces and urine contamination. Feed waste due to spillage and inaccessible feed was minimal and estimated to average 0.8%. Growth and weight maintenance in weanling and adult rats using the feeder were similar when compared to rats receiving pelleted feed ad libitum.

Small animal traversing gamma counter.

A whole body traverser was developed that provides a variety of radionuclide detection configurations for retention and distribution studies. Data from biologically incorporated radionuclides were shown to be less susceptible to geometrical problems with this whole body traverser than with the usual forms of whole body counters. When used in its fully rotational mode, the effects of photon energy and attenuation due to various body tissues, thicknesses, and radionuclide locations were minimized. Consistent presentation of all aspects of the sample produced greater than 95% correlation with the predictable data and less than 2% counting fluctuations. The whole body traverser was utilized in radiolabeled microsphere tracer studies for the determination of regional blood flow and as a static counter for long term retention studies.

Conjunctivorhinostomy: a surgical method for the control of epiphora in the dog and cat.

Conjunctivorhinostomy, a surgical technique for the control of epiphora, was developed for use in the dog and cat. The method was performed 32 times in 21 animals, with varying degrees of success. It was concluded that the technique has potential as an effective procedure.

Device for holding a variety of tissue culture vessels during microscopy.

A device for holding tissue culture tubes, plates and flasks has been designed for use in microscopy of cell cultures, which eliminates changing holders when using varied types or sizes of vessel.

A new feeder system for quantitating actual toxicant consumption by mice during feeding studies.

A new mouse feeder system was described which enables mice to be utilized for long-or short-term feeding studies of chemical toxicants. Quantitative toxicant consumption can be obtained. The use of granulated feed of particle size, 500-1000 mu, prevents bridging, thus assuring a constant supply of diet to the experimental animals. Comparative weight gain in female BALB/c Nctr BR mice showed no significant differences between the groups fed 500 ppm 2-fluorenylacetamide, control granulated feed, or pellets.