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31.
Vectorization of morpholino oligomers by the (R-Ahx-R)4 peptide allows efficient splicing correction in the absence of endosomolytic agents. 总被引:1,自引:0,他引:1
Sa?d Abes Hong M Moulton Philippe Clair Paul Prevot Derek S Youngblood Rebecca P Wu Patrick L Iversen Bernard Lebleu 《Journal of controlled release》2006,116(3):304-313
The efficient and non-toxic nuclear delivery of steric-block oligonucleotides (ON) is a prerequisite for therapeutic strategies involving splice correction or exon skipping. Cationic cell penetrating peptides (CPPs) have given rise to much interest for the intracellular delivery of biomolecules, but their efficiency in promoting cytoplasmic or nuclear delivery of oligonucleotides has been hampered by endocytic sequestration and subsequent degradation of most internalized material in endocytic compartments. In the present study, we compared the splice correction activity of three different CPPs conjugated to PMO(705), a steric-block ON targeted against the mutated splicing site of human beta-globin pre-mRNA in the HeLa pLuc705 splice correction model. In contrast to Tat48-60 (Tat) and oligoarginine (R(9)F(2)) PMO(705) conjugates, the 6-aminohexanoic-spaced oligoarginine (R-Ahx-R)(4)-PMO(705) conjugate was able to promote an efficient splice correction in the absence of endosomolytic agents. Our mechanistic investigations about its uptake mechanisms lead to the conclusion that these three vectors are internalized using the same endocytic route involving proteoglycans, but that the (R-Ahx-R)(4)-PMO(705) conjugate has the unique ability to escape from lysosomial fate and to access to the nuclear compartment. This vector, which has displays an extremely low cytotoxicity, the ability to function without chloroquine adjunction and in the presence of serum proteins. It thus offers a promising lead for the development of vectors able to enhance the delivery of therapeutic steric-block ON in clinically relevant models. 相似文献
32.
K-K Agbovi M Kolou L Fétéké D Haudrechy M-L North A-Y Ségbéna 《Transfusion Clinique et Biologique》2006,13(4):260-265
GOALS: 1) analyse the knowledge, attitudes and practices of Lome population about blood donation; 2) identify obstacles to blood donation among the population of Lome; 3) suggest some solutions to improve the performance of the National Blood Transfusion Centre (CNTS). METHODOLOGY: We have conducted a sample survey among the population of Lome from the 6th to 21st October 2003. Three hundred persons filled a questionnaire. RESULTS: In the sample, 183 (61%) were males. Their age ranged from 18 to 67 years with 2/3 of young peoples between 18 and 37 years. Pupils/students were 24,33%, wage-earners, 55% and the unemployed, 17,67%. More than the half of the investigated persons (54,67%) were unmarried and 96, 33% persons were literate. Nearly all the people (96,33%) knew about blood donation in Lome and they have received information mainly from friends, media and sensitization by the CNTS. Sixty-one percent of the investigated knew where blood is donated. All the investigated were unanimous about the vital role of blood. Whatever their religion, they recognized its sacred nature. The majority of the investigated (85%) were willing to donate blood. Only 95 people were donors. The reasons for non-donation were mainly related to the fear of catching diseases (31,71%) especially the HIV (9,76%), the lack of information (25,37%), the religious beliefs (19,51%) and the fear of knowing the result of one's HIV test. 277 people (92,33%) said that blood should be donated without remuneration. CONCLUSION: There is a growing interest in the blood donation among the population of Lome but new strategies must be elaborated to inform the population and motivate blood donors. 相似文献
33.
François Béïque Mohamed Ali Scott MacKenzie Mark Hynes 《Journal canadien d'anesthésie》2007,54(2):158-159
34.
35.
Activation of peripheral 5-HT4 receptors attenuates colonic sensitivity to intraluminal distension 总被引:2,自引:0,他引:2
b. greenwood-van meerveld k. venkova g. hicks † e. dennis † & m. d. crowell ‡ 《Neurogastroenterology and motility》2006,18(1):76-86
Tegaserod is a 5-HT(4) receptor partial agonist approved for the treatment of irritable bowel syndrome in women with constipation and in both men and women with chronic constipation. The efficacy of tegaserod is based on the importance of 5-HT(4) receptors regulating intestinal peristalsis and secretion, and possibly visceral sensory pathways. Our aim was to investigate the effect of tegaserod on colorectal sensitivity using models of normal and exaggerated responsiveness to colorectal distension (CRD). The visceromotor responses (VMR) to CRD at graded pressures (0-60 mmHg) were measured by the number of reflex abdominal contractions. Acute colorectal hypersensitivity was induced by intracolonic infusion of dilute acetic acid. Chronic hypersensitivity was observed in rats following spontaneous resolution of trinitrobenzenesulfonic acid-induced colitis. Rats with normosensitive colons served as controls. Tegaserod (0.1-10 mg kg(-1)) caused dose-dependent reduction of the VMR to CRD in control rats and in those with colonic hypersensitivity. 5-HT(4) antagonists reversed the effects of tegaserod in rats with normosensitive colons, and partially inhibited effects in rats with colonic hypersensitivity. Central administration of tegaserod had no inhibitory effect. These results support the assumption that colonic hypersensitivity could be normalized by tegaserod acting, at least in part, through peripheral 5-HT(4) receptors. 相似文献
36.
j. gonenne t. esfandyari m. camilleri d. d. burton d. a. stephens k. l. baxter a. r. zinsmeister † & a. e. bharucha 《Neurogastroenterology and motility》2006,18(10):911-918
Females are disproportionately affected by constipation, which is often aggravated during pregnancy. Bowel function also changes during the luteal phase of the menstrual cycle. The aim was to compare the effects of acute administration of female sex steroids on gastric emptying, small bowel transit and colonic transit in healthy postmenopausal subjects. A second aim was to determine whether withdrawal of the hormones was associated with a change in transit. Forty-nine postmenopausal females were randomized to receive for 7 days 400 mg day(-1) micronized progesterone, 0.2 mg day(-1) oestradiol, combination of the two, or placebo. Treatment groups were balanced on age. Participants underwent whole gut transit measurement by scintigraphy using a 99m-labeled technetium-egg meal and 111-labeled indium-charcoal via a delayed-release capsule. Transit measurement was repeated after withdrawal of the study medications. The primary endpoints were ascending colon (AC) emptying half-life time (t1/2) and colonic geometric centre (GC) at 24 h. Secondary analysis variables were GC at 4 and 48 h, gastric emptying t1/2 and colonic filling at 6 h. There was a significant overall effect of progesterone on colonic transit with shorter AC emptying t1/2 and significantly greater colonic GC at 48 h. No transit endpoints were altered by oestradiol or combined hormonal treatment relative to placebo. Oestradiol and progesterone resulted in looser stool consistency. Withdrawal of the hormone supplement was not associated with significant alteration in transit. Micronized progesterone does not retard colonic transit in postmenopausal females. 相似文献
37.
A capture monoclonal antibody-based assay has been established for detecting the p24 core protein and the gp51 envelope glycoprotein of bovine leukemia virus (BLV). This assay is rapid, highly sensitive and specific. Viral antigens in test samples were identified using mouse monoclonal antibody-coated or microtiter plates by adding labeled monoclonal antibodies with different epitope specificities. The choice of an appropriate epitope specificity for the specificity of monoclonal antibodies was important for optimal performance of the assay. Results of this assay were in agreement with the syncytia induction assay routinely used for detecting BLV production by cells in vitro. The sensitivity of monoclonal antibody assay was 0.5 ng/ml for p24 and 1.25 ng/ml for gp51, respectively. The specificity was demonstrated by immunoblotting. The assay can be performed in a few hours, is simple, and is comparable with more time-consuming assays with regard to sensitivity and specificity. 相似文献
38.
应用聚合酶链反应 限制性片段长度多态性技术 (PCR RFLP) ,以北京自然人群为基础 ,采用分层随机抽样的方法进行横断面研究 ,对 1 0 46人进行apoE基因分型 ,并分析不同特点人群apoE基因频率分布特点。结果表明 :1 )本组人群ε2、ε3、ε4基因频率分别为 9.1 %、81 .2 %和 9.7% ,男女和各年龄组间基因频率无显著差异 ;2 )与欧美国家相比 ,本组人群ε2基因频率增高 ,ε4频率减低 ,与日本人群相比也有相同趋势 ;3 )在空腹血糖受损及糖尿病人群中ε2频率明显增高 ;4)在高胆固醇血症人群中ε2频率减低、ε4基因频率增高 相似文献
39.
40.
Birsen Uçar Ayten Yakut Nurdan Kural Ferit Büyükaşık Erkan Vardareli 《Pediatric nephrology (Berlin, Germany)》1997,11(1):31-35
.We report five patients with Laurence-Moon-Bardet-Biedl syndrome (LMBBS) who had renal involvement. Intravenous pyelography
showed bilateral or unilateral calyceal clubbing and blunting in all patients. In addition, one patient had a parapelvic cyst
in the left kidney and another had bilateral lobulated renal outlines of the fetal type. One patient had a urinary concentrating
defect and two patients showed increased fractional sodium excretion. Estimated tubular phosphate reabsorption values were
in normal limits in all of five patients. No patient had a urine acidification defect, proteinuria, glycosuria, or hyperaminoaciduria.
One patient died from end-stage renal failure. The remaining four patients had normal serum creatinine values and estimated
creatinine clearances. 99mTechnetium-diethylenetriamine pentaacetate renal scanning showed prolonged and delayed concentration and delayed excretion
in three of the four patients who survived. A focal scar was determined on the left kidney of one of four patients by 99mtechnetium-dimercaptosuccinic acid renal scanning. All LMBBS cases with or without renal symptoms should be routinely evaluated
for renal abnormalities. Renal scanning is a valuable method, especially for determining the renal involvement in the early
stage of disease.
Received November 14, 1995; received in revised form and accepted May 23, 1996 相似文献