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991.
We report on the synthesis of various acridine (Acr)-spacer-nuclear localization signal (NLS) peptide conjugates and explore whether their use as NLS-labeling agent of plasmidic DNA could improve gene nuclear import and expression into cells when mediated by synthetic DNA complexes. As the conditions of successful use of the NLS properties to enhance gene transfer are not clear, and with the aim of detecting and defining the requirements of NLS-enhanced transfection, we investigated gene delivery and expression into various cell lines with various DNA complexes (lipoplexes or polyplexes) that were formulated for various N/P ratios from various preformed Acr-spacer-NLS/DNA complexes (1:1, 5:1 and 10:1 molar ratio). For the in vitro transfection assays, the lipoplexes and polyplexes were formulated from the preformed Acr-spacer-NLS/DNA complexes and dioctadecylamidoglycylspermine (DOGS)/dioleylphosphatidylethanolamine (DOPE) 1:1 mol and branched polyethyleneimine (PEI) 25 kDa, respectively, which are very efficient in vitro gene transfer systems. We show by fluorescence experiments that part of the acridine-NLS-conjugates remains intercalated within the plasmid for most of the N/P lipoplexes and polyplexes investigated. We show that, as several other studies performed with NLS-conjugates that are not covalently linked to DNA, the expression of the transgene is in most cases not improved upon complexation of plasmidic DNA with NLS-intercalating conjugates prior to its formulation as lipoplexes or polyplexes. 相似文献
992.
Barragan-Montero V Winum JY Molès JP Juan E Clavel C Montero JL 《European journal of medicinal chemistry》2005,40(10):1022-1029
The usefulness of vesicles to cargo material depends on the design of new ligands able to incorporate easily inside the bilayer and also to direct the vesicles to the targeted site. Therefore, the synthesis of two new rhamnose-bearing surfactants is described. The hydrophobic part consists of cholesterol (in compound 3) and citrylidene phloroglucinol (in compound 6). The ability of these two rhamnolipids to incorporate into a DPPC membrane and to form aggregates is investigated, respectively, by differential scanning calorimetry and by surface tension measurements. Those two new surfactants were incorporated in fluorescent liposomes to study their interactions with keratinocytes and skin sections. Intraliposomal delivery to keratinocytes was observed in both cases, even if the kinetics of delivery were different according to the rhamnosurfactant used. Skin sections were stained by both liposomal formulations, and different interactions between the liposomes and skin cells according to the surfactant used were noted. 相似文献
993.
Sarela AI Scott N Verbeke CS Wyatt JI Dexter SP Sue-Ling HM Guillou PJ 《Archives of surgery (Chicago, Ill. : 1960)》2005,140(7):644-649
HYPOTHESIS: High-grade dysplasia (HGD) of the gastric epithelium is associated with high prevalence of invasive carcinoma, and distinction by endoscopic biopsy is difficult. DESIGN: Cohort study, 1996 to 2003. SETTING: Tertiary care center. PATIENTS: Consecutive sample of 22 patients with initial diagnosis of gastric HGD by endoscopic biopsy. Biopsy specimens were separately reviewed by 3 experienced pathologists. Clinical management was individually decided. MAIN OUTCOME MEASURES: Strength of interpathologist agreement (kappa) and final pathological diagnosis. RESULTS: The diagnosis was revised to intramucosal carcinoma in 14% to 32% of patients or suspicious for invasive carcinoma in 23% to 41%. The strength of agreement between any 2 pathologists for distinguishing between dysplasia and invasive carcinoma was fair (kappa = 0.35-0.36). A diagnosis of intramucosal carcinoma or suspicious for invasive carcinoma by 2 pathologists correlated strongly with subsequent detection of invasive carcinoma. Three patients underwent gastrectomy for HGD, and invasive carcinoma was detected in all (2 patients, T1 N0; 1 patient, T2 N0). Six patients had invasive carcinoma on endoscopic surveillance at a median of 15 months (range, 3-34 months) after diagnosis of HGD and underwent endoscopic mucosal resection (2 patients, T1 NX), gastrectomy (2 patients, T1 N0), or no resection (2 patients). Another patient had metastatic gastric adenocarcinoma despite having a diagnosis of only HGD by endoscopy. Seven patients (32%) died of unrelated causes, without invasive carcinoma, at a median of 19 months (range, 1-38 months). Three patients were alive with persistent HGD at 26 to 61 months. Two patients had no dysplasia on follow-up. CONCLUSIONS: Experienced pathologists often disagreed in distinguishing invasive carcinoma from HGD in gastric biopsy specimens. One third of patients with gastric HGD died of causes unrelated to cancer. Invasive carcinoma was detected in 67% of the remainder. 相似文献
994.
Subcutaneous oxyntomodulin reduces body weight in overweight and obese subjects: a double-blind, randomized, controlled trial 总被引:11,自引:0,他引:11
Wynne K Park AJ Small CJ Patterson M Ellis SM Murphy KG Wren AM Frost GS Meeran K Ghatei MA Bloom SR 《Diabetes》2005,54(8):2390-2395
This study investigated the effect of subcutaneously administered oxyntomodulin on body weight in healthy overweight and obese volunteers. Participants self-administered saline or oxyntomodulin subcutaneously in a randomized, double-blind, parallel-group protocol. Injections were self-administered for 4 weeks, three times daily, 30 min before each meal. The volunteers were asked to maintain their regular diet and level of physical exercise during the study period. Subjects' body weight, energy intake, and levels of adipose hormones were assessed at the start and end of the study. Body weight was reduced by 2.3 +/- 0.4 kg in the treatment group over the study period compared with 0.5 +/- 0.5 kg in the control group (P = 0.0106). On average, the treatment group had an additional 0.45-kg weight loss per week. The treatment group demonstrated a reduction in leptin and an increase in adiponectin. Energy intake by the treatment group was significantly reduced by 170 +/- 37 kcal (25 +/- 5%) at the initial study meal (P = 0.0007) and by 250 +/- 63 kcal (35 +/- 9%) at the final study meal (P = 0.0023), with no change in subjective food palatability. Oxyntomodulin treatment resulted in weight loss and a change in the levels of adipose hormones consistent with a loss of adipose tissue. The anorectic effect was maintained over the 4-week period. Oxyntomodulin represents a potential therapy for obesity. 相似文献
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999.
Alex?SheffieldEmail author Glenn?Waller Francesca?Emanuelli James?Murray Caroline?Meyer 《Cognitive therapy and research》2005,29(6):787-802
This study describes the psychometric validation of the young parenting inventory (YPI), and tested specific hypotheses regarding
the link between one’s experience of their parent’s behaviors and the development of schema-level core beliefs. The YPI is
a measure of perceived parenting experiences, hypothesized to represent the origins of negative core beliefs. This preliminary
validation consisted of analyses of factor structure, internal consistency, test–retest reliability, and construct validity.
A large non-clinical student sample (N = 422) completed the YPI, and a subset also completed the Young Schema Questionnaire-Short form (YSQ-S). Factor analyses demonstrated
that a shorter version of the questionnaire (YPI-R) could be developed to represent coherent and meaningful perceptions of
each parent. The YPI-R consists of nine scales. Each scale had good test–retest reliability and adequate internal consistency.
Significant associations between the YPI-R scales and negative core beliefs (as measured by the YSQ-S) indicated partial construct
validity. At this preliminary stage, it can be concluded that the YPI-R has an acceptable level of psychometric utility. However,
the hypothesized parenting-negative core belief links were not all substantiated. 相似文献
1000.
Naylor MD Stephens C Bowles KH Bixby MB 《The American journal of nursing》2005,105(2):52-61; quiz 61-2