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241.
Oligoamines as catalytic sites for RNA hydrolysis are attached to 5'-end of [dT]16 using urethane bond. The [dT]16-pentaethylenehexamine hybrid promptly hydrolyzes poly[A] at pH 8, 50 degrees C. Definite importance of the complexation between the poly[A] and the [dT]16 moiety is confirmed by a marginal hydrolysis of poly[C]. Hydrolytic catalysis is ascribed to intramolecular acid-base cooperation of two or more amino residues in the oligoamines. 相似文献
242.
To reveal the importance of lysoposphatidylcholine (LPC) in patients with Type 2 diabetes (DM), LPC in low density lipoprotein (LDL) was determined by high performance liquid chromatography in 38 patients with Type 2 DM and 31 age and sex-matched non-diabetic controls. Stearoyl LPC (SLPC) and palmitoyl LPC (PLPC) were detected in LDL. The contents of both LPCs per gram protein in LDL were increased in diabetic patients compared with the non-diabetics (1.99+/-0.94mg SLPC and 3.02+/-1.81 mg PLPC vs 1.47+/-0.57 mg SLPC and 2.30+/-0.83 mg PLPC, mean +/- SD, p < 0.01 and p < 0.05, respectively). PLPC showed a weak correlation with the levels of fasting plasma glucose (FPG) and HbA1c (r=0.27 and r=0.33, p < 0.05 and p < 0.01, respectively). The diabetic patients with macroangiopathy showed higher levels of PLPC per gram protein compared to those without macroangiopathy (4.60+/-2.61 mg vs 2.53+/1.15 mg, respectively, p < 0.05). The LPC molecular species may participate in the atherogenicity of LDL in patients with Type 2 diabetes. 相似文献
243.
Anraku K Inoue T Sugimoto K Kudo K Okamoto Y Morii T Mori Y Otsuka M 《Bioorganic & medicinal chemistry》2011,19(22):6833-6841
A bifunctional molecule containing biotin and d-myo-inositol 1,3,4,5-tetrakisphosphate was synthesized. This molecule was designed on the basis of X-ray structure of the complex of d-myo-inositol 1,3,4,5-tetrakisphosphates, Ins(1,3,4,5)P(4), and Grp1 PH (general receptor of phosphoinositides pleckstrin homology) domain for the application to the widely employed biotin-avidin techniques. The building block of inositol moiety was synthesized starting with myo-inositol and assembled with the biotin-linker moiety through a phosphate linkage. The equilibrium dissociation constant K(D) of biotinylated Ins(1,3,4,5)P(4) binding of original Grp1 PH domain was 0.14 μM in pull-down analysis, which was comparable to that of unmodified Ins(1,3,4,5)P(4). Furthermore, biotinylated Ins(1,3,4,5)P(4) had an ability to distinguish Grp1 PH domain from PLCδ(1) PH domain. Thus, biotinylated Ins(1,3,4,5)P(4) retained the binding affinity and selectivity of original Grp1 PH domain, and realized the intracellular Ins(1,3,4,5)P(4) despite a tethering at the 1-phosphate group of inositol. 相似文献
244.
Ohwada J Ebiike H Kawada H Tsukazaki M Nakamura M Miyazaki T Morikami K Yoshinari K Yoshida M Kondoh O Kuramoto S Ogawa K Aoki Y Shimma N 《Bioorganic & medicinal chemistry letters》2011,21(6):1767-1772
Phosphatidylinositol 3-kinase (PI3K) is a lipid kinase and a promising therapeutic target for cancer. Using structure-based drug design (SBDD), we have identified novel PI3K inhibitors with a dihydropyrrolopyrimidine skeleton. Metabolic stability of the first lead series was drastically improved by replacing phenol with aminopyrimidine moiety. CH5132799, a novel class I PI3K inhibitor, exhibited a strong inhibitory activity especially against PI3Kα (IC50 = 0.014 μM). In human tumor cell lines with PI3K pathway activation, CH5132799 showed potent antiproliferative activity. CH5132799 is orally available and showed significant antitumor activity in PI3K pathway-activated human cancer xenograft models in mice. 相似文献
245.
246.
Use of loop‐mediated isothermal amplification to detect six groups of pathogens causing secondary lower respiratory bacterial infections in horses
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Microbial substitution occasionally occurs following the administration of antimicrobials to horses that have pneumonia or pleuropneumonia. Four specific loop‐mediated isothermal amplification (LAMP) assays were developed to detect some equine respiratory pathogens, namely strains of the Bacteroides–Prevotella group, Klebsiella pneumoniae, Stenotrophomonas maltophilia, and Staphylococcus aureus. These four LAMP assays and two previously published LAMP assays targeting Escherichia coli or Pseudomonas aeruginosa were used on clinical respiratory specimens and a high accordance found between the results of the LAMP assays and bacterial culture. Use of these LAMP assays could enable rapid detection of pathogenic bacteria and swift administration of the appropriate antimicrobials. 相似文献
247.
Kawasaki A Furukawa H Kondo Y Ito S Hayashi T Kusaoi M Matsumoto I Tohma S Takasaki Y Hashimoto H Sumida T Tsuchiya N 《Arthritis research & therapy》2011,13(2):R41-8
Introduction
The Toll-like receptor 7 (TLR7) gene, encoded on human chromosome Xp22.3, is crucial for type I interferon production. A recent multicenter study in East Asian populations, comprising Chinese, Korean and Japanese participants, identified an association of a TLR7 single-nucleotide polymorphism (SNP) located in the 3' untranslated region (3' UTR), rs3853839, with systemic lupus erythematosus (SLE), especially in males, although some difference was observed among the tested populations. To test whether additional polymorphisms contribute to SLE in Japanese, we systematically analyzed the association of TLR7 with SLE in a Japanese female population.Methods
A case-control association study was conducted on eight tag SNPs in the TLR7 region, including rs3853839, in 344 Japanese females with SLE and 274 healthy female controls.Results
In addition to rs3853839, two SNPs in intron 2, rs179019 and rs179010, which were in moderate linkage disequilibrium with each other (r 2 = 0.53), showed an association with SLE (rs179019: P = 0.016, odds ratio (OR) 2.02, 95% confidence interval (95% CI) 1.15 to 3.54; rs179010: P = 0.018, OR 1.75, 95% CI 1.10 to 2.80 (both under the recessive model)). Conditional logistic regression analysis revealed that the association of the intronic SNPs and the 3' UTR SNP remained significant after we adjusted them for each other. When only the patients and controls carrying the risk genotypes at the 3' UTR SNPpositionwere analyzed, the risk of SLE was significantly increased when the individuals also carried the risk genotypes at both of the intronic SNPs (P = 0.0043, OR 2.45, 95% CI 1.31 to 4.60). Furthermore, the haplotype containing the intronic risk alleles in addition to the 3' UTR risk allele was associated with SLE under the recessive model (P = 0.016, OR 2.37, 95% CI 1.17 to 4.80), but other haplotypes were not associated with SLE.Conclusions
The TLR7 intronic SNPs rs179019 and rs179010 are associated with SLE independently of the 3' UTR SNP rs3853839 in Japanese women. Our findings support a role of TLR7 in predisposition for SLE in Asian populations. 相似文献248.
Kawamoto T Abe Y Ito J Makino F Kojima Y Usui Y Ma J Morimoto S Yagita H Okumura K Takasaki Y Akiba H 《Arthritis research & therapy》2011,13(2):R47-12
Introduction
T cell immunoglobulin and mucin domain-2 (TIM-2) has been shown to regulate CD4 T cell activation. However, the role of TIM-2 in the autoimmune disease models has not been clarified yet. In this study, we investigated the effects of anti-TIM-2 monoclonal antibodies (mAbs) in collagen-induced arthritis (CIA) to determine whether TIM-2 contributes to the development of T helper (Th) 1 or Th17 cells and joint inflammation.Methods
DBA/1 mice were treated with anti-TIM-2 mAbs during the early or late phase of CIA. Type II collagen (CII)-specific CD4 T-cell proliferative response and cytokine production were assessed from lymph node cell culture. The serum levels of CII-specific antibody were measured by ELISA. The expression of TIM-2 on CD4 T cells or B cells was determined by flow cytometric analysis.Results
Administration of anti-TIM-2 mAbs in early phase, but not late phase, significantly exacerbated the development of CIA. Although anti-TIM-2 mAbs treatment did not affect the development of Th1 or Th17 cells in the draining lymph node, the serum levels of anti-CII antibodies were significantly increased in the anti-TIM-2-treated mice. TIM-2 expression was found on splenic B cells and further up-regulated by anti-immunoglobulin (Ig)M, anti-CD40, and interleukin(IL)-4 stimulation. In contrast, CD4 T cells did not express TIM-2 even when stimulated with both anti-CD3 and anti-CD28 mAbs. Interestingly, anti-TIM-2 mAbs enhanced proliferation and antibody production of activated B cells in vitro.Conclusions
TIM-2 signaling influences both proliferation and antibody production of B cells during the early phase of CIA, but not induction of Th1 or Th17 cells. 相似文献249.
ABSTRACT: INTRODUCTION: We were able to treat a patient with acute exacerbation of chronic obstructive pulmonary disease who also suffered from sleep-disordered breathing by using the average volume-assured pressure support mode of a Respironics V60 Ventilator (Philips Respironics: United States). This allows a target tidal volume to be set based on automatic changes in inspiratory positive airway pressure. This removed the need to change the noninvasive positive pressure ventilation settings during the day and during sleep. The Respironics V60 Ventilator, in the average volume-assured pressure support mode, was attached to our patient and improved and stabilized his sleep-related hypoventilation by automatically adjusting force to within an acceptable range. CASE PRESENTATION: Our patient was a 74-year-old Japanese man who was hospitalized for treatment due to worsening of dyspnea and hypoxemia. He was diagnosed with acute exacerbation of chronic obstructive pulmonary disease and full-time biphasic positive airway pressure support ventilation was initiated. Our patient was temporarily provided with portable noninvasive positive pressure ventilation at night-time following an improvement in his condition, but his chronic obstructive pulmonary disease again worsened due to the recurrence of a respiratory infection. During the initial exacerbation, his tidal volume was significantly lower during sleep (378.9 +/- 72.9mL) than while awake (446.5 +/- 63.3mL). A ventilator that allows ventilation to be maintained by automatically adjusting the inspiratory force to within an acceptable range was attached in average volume-assured pressure support mode, improving his sleep-related hypoventilation, which is often associated with the use of the Respironics V60 Ventilator. Polysomnography performed while our patient was on noninvasive positive pressure ventilation revealed obstructive sleep apnea syndrome (apnea-hypopnea index = 14), suggesting that his chronic obstructive pulmonary disease was complicated by obstructive sleep apnea syndrome. CONCLUSION: In cases such as this, in which patients with severe acute respiratory failure requiring full-time noninvasive positive pressure ventilation therapy also show sleep-disordered breathing, different ventilator settings must be used for waking and sleeping. On such occasions, the Respironics V60 Ventilator, which is equipped with an average volume-assured pressure support mode, may be useful in improving gas exchange and may achieve good patient compliance, because that mode allows ventilation to be maintained by automatically adjusting the inspiratory force to within an acceptable range whenever ventilation falls below target levels. 相似文献
250.
Yoshinari Tanaka 《Theoretical Ecology》2012,5(1):83-98
The response of ecological communities to environmental disturbances depends not just on the number of species they contain
but also on the functional diversity of the constituent species; greater variation in the tolerance of species to different
environmental disturbances is generally thought to confer greater resistance to the community. Here, I investigate how the
functional diversity of communities changes with environmental disturbances. Specifically, I assume that there is variation
in traits among species that confer tolerance or sensitivity to environmental disturbances. When a disturbance occurs, variation
in species tolerances causes changes in the relative abundances of species, which in turn changes the average tolerance of
the community. For example, if tolerance to an environmental disturbance is conferred by large body size, then the environmental
disturbance should be expected to increase the average body size of individuals in the community. Despite this expectation,
ecological interactions among species can affect the average community response. For example, if larger species are also strong
competitors with each other, then this might reduce the increase in average body size in the community, because interspecific
competition limits the grow in population density of large bodied species. Similarly, when disturbances affect multiple traits,
the covariance in the distribution of trait values among species may restrict the response of any one trait; if two traits
provide tolerance to the same disturbance but negatively covary among species, then the response of one trait will limit the
response of the other trait at the community level. Using a Lotka–Volterra model for competitive communities, I derive general
formulae that generate explicit predictions about the changes in average trait values in a community subject to environmental
disturbances. These formulae demonstrate that competition can impede the change in average community trait values. However,
the impediment is not considerable in comparison to the predominant factors of trait variances and species selection effects
when species with the most similar trait values also experience the greatest interspecific competition. Similarly, negative
covariances among different traits that confer resistance to the same environmental disturbance will impede their responses.
I illustrate these results using phytoplankton data from a whole-lake experiment in which manipulation to the zooplankton
community created a disturbance to the phytoplankton that changed the selective consumption of large vs. small phytoplankton. 相似文献