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Bergenin and menisdaurin are biologically active components which are found in plant Flueggea virosa (Phyllanthaceae). Bergenin has pharmacological actions such as chemopreventive and antihepatotoxic while menisdaurin has an anti-viral activity which needs its evaluation by an analytical method (UPLC-PDA method) that can be applied to the quality control of pharmaceutical preparations. The developed UPLC-PDA method was applied for identification and quantification of standards bergenin and menisdaurin in the methanol extract of F. virosa (FVME). The analysis was carried out using Eclipse C18 (4.6?×?100?mm, 3.5?µm) UPLC column. The optimized chromatographic condition was achieved at 0.16?mL/min flow rate using gradient system with acetonitrile and water as mobile phase. Both biomarkers were measured at λmax 235?nm in PDA detector at ambient temperature. The developed method furnished sharp and intense peaks of menisdaurin and bergenin at Rt?=?2.723 and 3.068?min, respectively along with r2?>?0.99 for both. The recoveries of bergenin and menisdaurin were found in the range of 99.37–101.49% and 98.20–100.08%, respectively. With other validation data, including precision, specificity, accuracy, and robustness, this method demonstrated excellent reliability and sensitivity. The separation parameters i.e. retention, separation, and resolution factors for resolved standards (bergenin and menisdaurin) were >1, which showed good separation. The quantity of bergenin and menisdaurin in the FVME sample was found as 15.16 and 3.28% w/w, respectively. The developed UPLC-PDA method could be conveniently adopted for the routine quality control analysis.  相似文献   
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Gastrocutaneous fistula after gastrostomy tube removal may persist for a prolonged period. We present a case of a 58-year-old woman with a GCF that had persisted for 5 months following the removal of an endoscopically-placed gastrostomy tube (PEG). Conservative therapy with anti-acid medications and administering motility agents was unsuccessful. For the closure of the GCF, the endoscopic metal clips were used to close the fistula.  相似文献   
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Purpose

The objective of this study was to determine the impact of a low-fidelity simulation model on mastering the sterile technique during placement of epidural catheters.

Methods

Trainees, including residents and fellows, were given conventional teaching consisting of a lecture and a video demonstration on the appropriate sterile technique to apply during the placement of epidural catheters. The trainees were then provided with a one-on-one demonstration session using a low-fidelity Styrofoam? epidural model, followed by a series of simulation sessions. After conventional teaching and following each simulation session, the trainees were assessed on their performance until competence was achieved based on a 15-point checklist. The retention of competence was subsequently evaluated bi-weekly in clinical practice for four assessments.

Results

Twenty-one trainees participated in the study. The average score for the residents following conventional teaching was 6.0 out of 15 points on the checklist. Following the initial one-on-one hands-on demonstration, the average score increased to 10.8 (difference = 4.8, 95% confidence interval (CI): 3.3 to 6.2; P < 0.001). The average score for the fellows following conventional teaching was 7.9 out of 15 points on the checklist. Following the initial one-on-one hands-on demonstration the average score increased to 11.2 (difference = 3.3, 95% CI: 0.05 to 6.6; P = 0.047). During the retention of competence phase, scores ranged from 13-15 for both residents and fellows.

Conclusion

This study describes a comprehensive teaching model for mastering the sterile technique during epidural catheter placement. It suggests that low-fidelity simulation improves the learning process when used in addition to conventional teaching.  相似文献   
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Introduction

The median survival of patients with glioblastoma multiforme (astrocytoma grade 4) remains less than 18 months despite radical surgery, radiotherapy and systemic chemotherapy. Surgical implantation of chemotherapy eluting wafers into the resection cavity has been shown to improve length of survival but the current licensed therapy has several drawbacks. This paper investigates in vivo efficacy of a novel drug eluting paste in glioblastoma.

Methods

Poly(lactic-co-glycolic acid)/poly(ethylene glycol) (PLGA/PEG) self-sintering paste was loaded with the chemotherapeutic agent etoposide and delivered surgically into partially resected tumours in a flank murine glioblastoma xenograft model.

Results

Surgical delivery of the paste was successful and practical, with no toxicity or surgical morbidity to the animals. The paste was retained in the tumour cavity, and preliminary results suggest a useful antitumour and antiangiogenic effect, particularly at higher doses. Bioluminescent imaging was not affected significantly by the presence of the paste in the tumour.

Conclusions

Chemotherapy loaded PLGA/PEG paste seems to be a promising technology capable of delivering active drugs into partially resected tumours. The preliminary results of this study suggest efficacy with no toxicity and will lead to larger scale efficacy studies in orthotopic glioblastoma models.  相似文献   
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