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991.
Establishing realistic exposure scenarios is critical for cytotoxic investigation of silver nanoparticles (AgNP) in the gastrointestinal tract. This study investigated the potential interaction with and effect of biofluid components, namely cholic acid, deoxycholic acid and ursodeoxycholic acid, on AgNP toxicity. Two cell lines corresponding to organs related to the biofluid components were employed. These were HepG‐2 a hepatocellular carcinoma derived from liver tissue and Hep2 an epithelial cell line. Physiochemical and cytotoxic screening was performed and the ability of biofluid components to modify AgNP cytotoxicity was explored. No alteration to the physiochemical characteristics of AgNP by biofluid components was demonstrated. However, biofluid component addition resulted in alteration of AgNP toxicity. Greater reactive oxygen species induction was noted in the presence of cholic acid and deoxycholic acid. Ursodeoxycholic acid demonstrated no modification of toxicity in HepG‐2 cells; however, significant modification was noted in Hep2 cells. It is concluded that biofluid components can modify AgNP toxicity but this is dependent on the biofluid component itself and the location where it acts. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
992.
The increasing use of cobalt oxide (Co3O4) nanoparticles (NPs) in several applications and the suggested genotoxic potential of Co‐oxide highlight the importance of evaluating Co3O4 NPs toxicity. Cyto‐genotoxic and inflammatory effects induced by Co3O4 NPs were investigated in human alveolar (A549), and bronchial (BEAS‐2B) cells exposed to 1–40 µg ml–1. The physicochemical properties of tested NPs were analysed by transmission electron microscopy (TEM) and dynamic light scattering (DLS). Cytotoxicity was studied to analyze cell viability (WST1 test) and membrane damage (LDH assay), direct/oxidative DNA damage was assessed by the Formamido‐pyrimidine glycosylase (Fpg)‐modified comet assay and inflammation by interleukin (IL)‐6, IL‐8 and tumor necrosis factor‐alpha (TNF‐α) release (ELISA). In A549 cells, no cytotoxicity was found, whereas BEAS‐2B cells showed a viability reduction at 40 µg ml–1 and early membrane damage at 1, 5 and 40 µg ml–1. In A549 cells, direct and oxidative DNA damage at 20 and 40 µg ml–1 were detected without any effects on cytokine release. In BEAS‐2B cells, significant direct DNA damage at 40 µg ml–1 and significant oxidative DNA damage with a peak at 5 µg ml–1, that was associated with increased TNF‐α release at 1 µg ml–1 after 2 h and increased IL‐8 release at 20 µg ml–1 after 24 h, were detected. The findings show in the transformed alveolar cells no cytotoxicity and genotoxic/oxidative effects at 20 and 40 µg ml–1. In normal bronchial cells, moderate cytotoxicity, direct DNA damage only at the highest concentration and significant oxidative‐inflammatory effects at lower concentrations were detected. The findings confirm the genotoxic‐oxidative potential of Co3O4 NPs and show greater sensitivity of BEAS‐2B cells to cytotoxic and oxidative‐inflammatory effects suggesting the use of different cell lines and multiple end‐points to elucidate Co3O4 NPs toxicity. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
993.

Aims

Custirsen (OGX-011/TV-1011), a second-generation antisense oligonucleotide (ASO) that reduces clusterin production, is under investigation with chemotherapy in patients with solid tumours. Custirsen is associated with constitutional symptoms (CS) that may interfere with clinical pharmacology investigations, such as QT interval studies. Experience with other ASOs suggests NSAID premedication may ameliorate CS, but we observed suboptimal outcomes in healthy subjects given custirsen and NSAIDs. We sought to establish a custirsen regimen for future clinical pharmacology studies in healthy subjects.

Methods

Subjects received custirsen (640 mg intravenously over 120 min) with dexamethasone premedication or increasing doses (320, 480, 640 mg over 6 days) of custirsen with dexamethasone premedication, then one full custirsen dose without premedication on day 8. Incidence/severity of adverse events (AEs) and extensive electrocardiogram readings were evaluated. Pharmacokinetic parameters were estimated.

Results

AEs included CS, elevated transaminases and prolonged activated partial thromboplastin time (aPTT) that were predominantly grade 1/2. Administration of increasing custirsen doses and dexamethasone premedication reduced the incidence of CS associated with full dose custirsen. Transaminase elevation showed a dose-dependent effect (0% at days 2, 4, 27% at day 6) with the highest custirsen doses. Increasing doses of custirsen may have mitigated the severity but not incidence of aPTT prolongation. Neither regimen was associated with cardiac repolarization changes in QT values or concentration–effect analyses. The custirsen pharmacokinetic profile was consistent with previous experience.

Conclusion

Escalation of custirsen dose combined with dexamethasone premedication reduced CS associated with full dose custirsen and should be considered in future clinical pharmacology studies of custirsen.  相似文献   
994.

Background

Dropout from child and adolescent psychotherapy is a common phenomenon which can have negative consequences for the individual later in life. It is therefore important to gain insight on dropout risk factors.

Objective

Several potential risk factors [ethnic minority status, a lower socioeconomic status (SES), and higher problem severity] were analyzed in present study. Innovations are that these risk factors were examined for children and adolescents separately, and a distinction was made in termination status between referred patients, dropouts and completers.

Methods

For ethnic majority and minority outpatient children (age 5–11, n = 399) and adolescents (age 12–20, n = 352) problem severity, ethnic background, SES, and treatment termination status (completer, dropout, referral) were specified. Multinomial logistic regression models were used as main method of analysis.

Results

For children, a Moroccan/Turkish ethnicity and higher externalizing scores were risk factors for being referred. For adolescents, a Surinamese/Antillean ethnicity, being female, being older, and lower parental SES occupation levels were risk factors for dropout.

Conclusions

Different dropout risk profiles emerged for children versus adolescents, and for dropouts versus referrals. Also, it depended on the specific ethnic background whether ethnic minority status was a predictor for dropout, and the relationship between SES and termination status differed by whether parental SES occupation or parental SES education were used as SES indicator. Professionals should thus be aware of these potential risk factors for dropout or referral when treating children and adolescents.
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The development of compounds with enhanced activity and selectivity by a conserved spatial orientation of the pharmacophore elements has a long history in medicinal chemistry. Rigidified compounds are an example of this concept. However, the intramolecular interactions were seldom used as a basis for conformational restraints. Here, we show the weak intramolecular interactions that contribute to the relatively well-conserved geometry of N1-arylsulfonyl indole derivatives. The structure analysis along with quantum mechanics calculations revealed a crucial impact of the sulfonyl group on the compound geometry. The weak intramolecular C–H⋯O interaction stabilizes the mutual "facing" orientation of two aromatic fragments. These findings extend the pharmacological interpretation of the sulfonyl group role from the double hydrogen bond acceptor to the conformational scaffold based on intramolecular forces. This feature has, to date, been omitted in in silico drug discovery. Our results should increase the awareness of researchers to consider the conformational preference when designing new compounds or improving computational methods.

The impact of weak intramolecular C–H⋯O interactions on the conformational stability of bis-arylsulfones is discussed, suggesting different role of sulfonyl group in the ligand – 5HT6 receptor interaction.  相似文献   
1000.

Objectives

This study examines whether the information used to inform hospital choice, and the sources of that information, varies with patients’ socio‐demographic characteristics. It also examines whether information used by patients to inform choice is associated with attending their local hospital.

Methods

A survey of 1033 patients who were offered a choice of hospital provider for elective treatment in England. Logistic regression was used to examine associations between patient characteristics and information used to inform choice of a hospital provider and sources of information used.

Results

Factors most important to patients in choosing a hospital were quality of care, cleanliness, standard of facilities and reputation. While quality of care and related factors are important to the majority of patients, those with lower levels of education were more likely to report that location and appointment times were important. Those who thought quality important were more likely to attend their local hospital provider. The main sources of information used to inform choice of hospital were own experience, family and friends and the general practitioner (GP). Patients who sought advice from their GP or booking advisors were less likely to attend their local hospitals.

Conclusions

Differences among patients as to what factors are important when choosing a hospital provider and what information and support they access suggest there needs to be a variety of information sources and support available to promote choice. Greater shared decision making through active involvement and support by GPs or booking advisors may be required if they are to make choices in line with their preferences.  相似文献   
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