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271.
Suryapranata H Boland JL Pieper M Legrand VL Bonnier JJ Juliard JM Vrolix MC Seabra-Gomes R Hamburger JN Roguin A Oosterwijk C Van Es GA Beyar R Serruys PW 《International journal of cardiovascular interventions》2000,3(1):21-28
BACKGROUND: Although safety and efficacy of the beStent (Medtronic Inc., Santa Rosa, CA, USA) have been described, the long-term angiographic and clinical outcomes have yet to be investigated. The ROSE (Registry for Optimal beStent Evaluation) trial was designed to assess the procedural safety of single 15 mm beStent implantation, and the six-month angiographic and 12-month clinical outcomes of patients treated with this novel coronary stent. METHODS: Patients with angina and a single de novo lesion in a native coronary artery of >/=2.75 mm diameter were included in this multicenter, prospective, observational trial. Clinical follow-up was obtained at one, six and 12 months. Angiography was performed before and after the stent implantation and at six months. The primary end-point included major adverse cardiac events (death, myocardial infarction and target lesion revascularization), major bleeding complications, and thrombotic occlusions at one-month follow-up. Secondary end-points were major cardiac-event-free survival at six- and 12-month follow-up and angiographic restenosis at six months. A total of 120 patients (80% male, mean age 58.6 +/- 10.6 years) with stable (48%) or unstable (44%) angina pectoris were allocated. The target vessel reference diameter pre-procedure was 2.85 +/- 0.52 mm. RESULTS: Minimal lumen diameter pre/post and at follow-up was 0.97 +/- 0.28 mm, 2.53 +/- 0.40 mm and 1.86 +/- 0.63 mm, respectively. Restenosis rate according to the >50% diameter stenosis criterion at six-month follow-up was 21.5%. At 12 months, the event-free survival rate was 75% (no deaths, two Q-wave and seven non-Q-wave infarctions, five bypass surgery interventions and 16 target lesion revascularizations), whilst 87% of the patients were free of angina pectoris. CONCLUSION: Despite the relatively high percentage of small vessels, the outcome of the ROSE trial is comparable to those observed in previous stent trials, indicating that the coronary beStent is safe and effective as a primary device for the treatment of native coronary artery lesions in patients with (un)stable angina pectoris. 相似文献
272.
Li T Jinsmaa Y Nedachi M Miyazaki A Tsuda Y Ambo A Sasaki Y Bryant SD Marczak E Li Q Swartzwelder HS Lazarus LH Okada Y 《Bioorganic & medicinal chemistry》2007,15(3):1237-1251
N-Allylation (-CH(2)-CHCH(2)) of [Dmt(1)]endomorphins yielded the following: (i) [N-allyl-Dmt(1)]endomorphin-2 (Dmt=2',6'-dimethyl-l-tyrosine) (12) and [N-allyl-Dmt(1)]endomorphin-1 (15) (K(i)mu=0.45 and 0.26nM, respectively) became mu-antagonists (pA(2)=8.59 and 8.18, respectively) with weak delta-antagonism (pA(2)=6.32 and 7.32, respectively); (ii) intracerebroventricularly administered 12 inhibited morphine-induced CNS-mediated antinociception in mice [AD(50) (0.148ng/mouse) was 16-fold more potent than naloxone], but not spinal antinociception, and (iii) 15 reversed the alcohol-elevated frequency in spontaneous inhibitory post-synaptic currents (IPSC) in hippocampal CA1 pyramidal cells in rat brain slices (P=0.0055). Similarly, N-allylation of the potent mu-opioidmimetic agonists, 1,6-bis-[H-Dmt-NH]-hexane and 3,6-bis-[Dmt-NH-propyl]-2(1H)-pyrazinone, converted them into mu-antagonists (pA(2)=7.23 and 7.17 for the N-allyl-derivatives 17 and 19, respectively), and exhibited weak delta-antagonism. Thus, N-allylation of Dmt containing opioid peptides or opioidmimetics continues to provide a facile means to convert selective mu-opioid agonists into potent mu-opioid antagonists. 相似文献
273.
Salvadori S Trapella C Fiorini S Negri L Lattanzi R Bryant SD Jinsmaa Y Lazarus LH Balboni G 《Bioorganic & medicinal chemistry》2007,15(22):6876-6881
Opioid compounds with mixed micro agonist/delta antagonist properties could be used as analgesics with low propensity to induce tolerance and dependence. Here we report the synthesis of a new designed multiple ligand deriving from the micro selective agonist endomorphin-2 and the delta selective antagonist pharmacophore Dmt-Tic. As predicted, the resulting bivalent ligand showed a micro agonist/delta antagonist profile deriving from the corresponding activities of each pharmacophore. 相似文献
274.
Balboni G Onnis V Congiu C Zotti M Sasaki Y Ambo A Bryant SD Jinsmaa Y Lazarus LH Lazzari I Trapella C Salvadori S 《Bioorganic & medicinal chemistry》2007,15(9):3143-3151
A wide range of activities are induced by Lys when introduced at C-terminus of the delta-opioid Dmt-Tic pharmacophore through the alpha-amine group, including: improved delta-antagonism, mu-agonism and mu-antagonism. Here we report the synthesis of a new series of compounds with the general formula H-Dmt-Tic-NH-(CH(2))(4)-CH(R)-R' (R=-NH(2), -NH-Ac, -NH-Z; R'=CO-NH-Ph, -CO-NH-CH(2)-Ph, -Bid) in which Lys is linked to Dmt-Tic through its side-chain amine group. All new compounds (1-9) displayed potent and selective delta-antagonism (MVD, pA(2)=7.81-8.27), which was independent of the functionalized alpha-amine and carboxylic groups of C-terminal Lys. This behaviour suggests a direct application as a prototype intermediate, such as Boc-Dmt-Tic-epsilon-Lys(Z)-OMe, which could be successfully applied in the synthesis (after Z or methyl ester removal) of unique designed multiple ligands containing the pharmacophore of the quintessential delta-antagonist Dmt-Tic and another opioid or biologically active non-opioid ligand. 相似文献
275.
Background
A major cornerstone of evolutionary biology theory is the explanation of the emergence of cooperation in communities of selfish individuals. There is an unexplained tendency in the plant and animal world – with examples from alpine plants, worms, fish, mole-rats, monkeys and humans – for cooperation to flourish where the environment is more adverse (harsher) or more unpredictable. 相似文献276.
L S Forsberg S C Lazarus N Seno R DeVinney G H Caughey W M Gold 《Biochimica et biophysica acta》1988,967(3):416-428
The cell-associated proteoglycans synthesized by three dog mastocytoma cell lines were isolated and their structural features compared. The lines were propagated as subcutaneous tumors in athymic mice for over 25 generations. In primary cell culture, all three lines incorporated [35S]sulfate into high molecular weight proteoglycans which were heterogeneous in size and glycosaminoglycan content. Two lines, BR and G, synthesized both a heparin proteoglycan (HPG) and a chondroitin sulfate proteoglycan (ChSPG) in different proportions. The third line, C2, synthesized predominantly a ChSPG with little or no detectable heparin. Gel filtration of the 35S-labeled HPG and ChSPG from the BR line on Sepharose CL-4B in dissociative conditions (4 M guanidine, Triton X-100) yielded a major polydisperse peak (Kav = 0.22) accounting for 70% of 35S activity. Under aggregating conditions (0.1 M sodium acetate) on Sepharose CL-4B, the BR proteoglycans eluted in the excluded volume. Proteoglycans from lines G and C2 also eluted in the void volume under nondissociative conditions, however the C2 line yielded additional fractions of smaller hydrodynamic size (Kav = 0.81) suggesting the presence of intracellular proteoglycan cleavage products or incompletely processed proteoglycans. As assessed by dissociative chromatography on Sepharose CL-4B, proteoglycans from the BR line were resistant to proteinase cleavage under conditions which degraded a rat chondrosarcoma proteoglycan. For all lines, glycosaminoglycans released by pronase/alkaline-borohydride had molecular weights ranging from 20,000 to 50,000 on gel filtration. For line BR, 75% of 35S-labeled glycosaminoglycans were degraded to oligosaccharides by nitrous acid, and the remaining 25% were degraded by chondroitinase ABC. Corresponding percentages for line G were 89% and 11%, and for line C2, 2% and 98%. Paper chromatography of the chondroitinase digestion products from lines BR and C2 showed products corresponding to unsaturated standards delta Di-diSB and delta Di-diSE, derived from the disaccharides IdoUA-2-SO4----GalNAc-4-SO4 and GlcUA----GalNAc-4,6-diSO4 respectively, in addition to smaller amounts of monosulfated disaccharides. Glycans from lines C2 and BR contained small quantities of a trisulfated disaccharide which was degraded to delta Di-diSB upon incubation with chondro-6-sulfatase. The results demonstrate the simultaneous presence of heparin and polysulfated chondroitin sulfate in dog mast cells of clonal origin. 相似文献
277.
Anouk Schurink Anna Wolc Bart J Ducro Klaas Frankena Dorian J Garrick Jack CM Dekkers Johan AM van Arendonk 《遗传、选种与进化》2012,44(1):31
Background
Insect bite hypersensitivity is a common allergic disease in horse populations worldwide. Insect bite hypersensitivity is affected by both environmental and genetic factors. However, little is known about genes contributing to the genetic variance associated with insect bite hypersensitivity. Therefore, the aim of our study was to identify and quantify genomic associations with insect bite hypersensitivity in Shetland pony mares and Icelandic horses in the Netherlands.Methods
Data on 200 Shetland pony mares and 146 Icelandic horses were collected according to a matched case–control design. Cases and controls were matched on various factors (e.g. region, sire) to minimize effects of population stratification. Breed-specific genome-wide association studies were performed using 70 k single nucleotide polymorphisms genotypes. Bayesian variable selection method Bayes-C with a threshold model implemented in GenSel software was applied. A 1 Mb non-overlapping window approach that accumulated contributions of adjacent single nucleotide polymorphisms was used to identify associated genomic regions.Results
The percentage of variance explained by all single nucleotide polymorphisms was 13% in Shetland pony mares and 28% in Icelandic horses. The 20 non-overlapping windows explaining the largest percentages of genetic variance were found on nine chromosomes in Shetland pony mares and on 14 chromosomes in Icelandic horses. Overlap in identified associated genomic regions between breeds would suggest interesting candidate regions to follow-up on. Such regions common to both breeds (within 15 Mb) were found on chromosomes 3, 7, 11, 20 and 23. Positional candidate genes within 2 Mb from the associated windows were identified on chromosome 20 in both breeds. Candidate genes are within the equine lymphocyte antigen class II region, which evokes an immune response by recognizing many foreign molecules.Conclusions
The genome-wide association study identified several genomic regions associated with insect bite hypersensitivity in Shetland pony mares and Icelandic horses. On chromosome 20, associated genomic regions in both breeds were within 2 Mb from the equine lymphocyte antigen class II region. Increased knowledge on insect bite hypersensitivity associated genes will contribute to our understanding of its biology, enabling more efficient selection, therapy and prevention to decrease insect bite hypersensitivity prevalence. 相似文献278.
Flavie Tortereau Hélène Gilbert Henri CM Heuven Jean-Pierre Bidanel Martien AM Groenen Juliette Riquet 《遗传、选种与进化》2010,42(1):42
Background
In pig, a number of experiments have been set up to identify QTL and a multitude of chromosomal regions harbouring genes influencing traits of interest have been identified. However, the mapping resolution remains limited in most cases and the detected QTL are rather inaccurately located. Mapping accuracy can be improved by increasing the number of phenotyped and genotyped individuals and/or the number of informative markers. An alternative approach to overcome the limited power of individual studies is to combine data from two or more independent designs.Methods
In the present study we report a combined analysis of two independent design (a French and a Dutch F2 experimental designs), with 2000 F2 individuals. The purpose was to further map QTL for growth and fatness on pig chromosomes 2, 4 and 6. Using QTL-map software, uni- and multiple-QTL detection analyses were applied separately on the two pedigrees and then on the combination of the two pedigrees.Results
Joint analyses of the combined pedigree provided (1) greater significance of shared QTL, (2) exclusion of false suggestive QTL and (3) greater mapping precision for shared QTL.Conclusions
Combining two Meishan x European breeds F2 pedigrees improved the mapping of QTL compared to analysing pedigrees separately. Our work was facilitated by the access to raw phenotypic data and DNA of animals from both pedigrees and the combination of the two designs with the addition of new markers allowed us to fine map QTL without phenotyping additional animals. 相似文献279.
Costs of fly control practices were estimated for 26 New York and Maryland dairy farms. Objectives were to characterize existing practices, compare them with the cost of more frequent and complete manure removal to reduce fly breeding, and to compare costs of manure removal and insecticide application. Information was collected in scouting visits and personal interviews of farm operators. Equipment, labor, and bedding costs were included for manure removal. Insecticide application costs included chemicals and labor for application. A typical farm with a stanchion barn had manure removal costs of $0.348 per cow per day. Recommended changes would increase costs by $0.016-0.033 per cow per day. Insecticide costs averaged $0.021 per cow per day. It may be possible to eliminate many of the insecticide applications on the farms by using the recommended 7-d manure removal practice. Even if insecticides are not eliminated entirely, increased manure removal costs would be offset by some reduction in insecticide cost. This also would have the additional benefit of greatly slowing the development of insecticide resistance by the flies. 相似文献
280.
Antony Kaspi Mark Ziemann Samuel T Keating Ishant Khurana Timothy Connor Briana Spolding Adrian Cooper Ross Lazarus Ken Walder Paul Zimmet Assam El-Osta 《Epigenetics》2014,9(10):1329-1338
Current computational methods used to analyze changes in DNA methylation and chromatin modification rely on sequenced genomes. Here we describe a pipeline for the detection of these changes from short-read sequence data that does not require a reference genome. Open source software packages were used for sequence assembly, alignment, and measurement of differential enrichment. The method was evaluated by comparing results with reference-based results showing a strong correlation between chromatin modification and gene expression. We then used our de novo sequence assembly to build the DNA methylation profile for the non-referenced Psammomys obesus genome. The pipeline described uses open source software for fast annotation and visualization of unreferenced genomic regions from short-read data. 相似文献