Enhancement of glutathione and g-glutamylcysteine synthetase,the rate limiting enzyme of glutathione synthesis,by chemoprotective plant-derived food and beverage components in the human hepatoma cell line HepG2

Glutathione (GSH) is an important antioxidant and cofactor of detoxifying metabolism. Therefore, elevation of GSH as achieved by inducing g-glutamylcysteine synthetase (GCS), the limiting enzyme of GSH synthesis, may contribute to chemoprevention against cancer. In previous animal studies, increases in GCS were mainly found in liver and other organs that are not easily accessible in humans. Thus, employment and evaluation of alternative systems such as human-derived cell lines are encouraged. In the present experiment, we used the hepatoma cell line HepG2 to investigate the response of GCS and GSH to five plant-derived chemoprotectants contained in regularly consumed foodstuffs and beverages (kahweol/cafestol [K/C] [15.5-62.0 mM], a-angelicalactone [100-400 mM], benzyl isothiocyanate [1.7-5.0 mM], diallyl sulfide [175-700 mM], and quercetin [10-50 mM]). All treatments led to dose-dependent increases in both GCS activity and GSH concentration. Time course studies with K/C indicated that the enhancement of GCS preceded that of GSH, suggesting a causal relationship. K/C did not enhance g-glutamyl transpeptidase, a further enzyme that assists GSH-related chemoprotection. Although GCS induction has been suggested to require an initial short-lived GSH depletion, we did not find any decrease in GSH after 3 h of incubation with K/C. In summary, HepG2 cells were shown to be a useful model to investigate the capacity of potential chemoprotectants to enhance GCS and GSH. To our knowledge, the present study is also the first to show increases in GCS by K/C and a-angelicalactone in vitro and by diallyl sulfide and quercetin in any system.     

Anterior chamber angle measurement with optical coherence tomography: intraobserver and interobserver variability

PURPOSE: To assess intraobserver and interobserver variability of anterior segment optical coherence tomography (AS-OCT) as an objective diagnostic tool to quantify the anterior chamber angle and opening width. SETTING: University Eye Clinic, Lübeck, Germany. METHODS: The anterior chamber angle and opening width were assessed in 18 eyes of 9 healthy volunteers by 2 observers. Intraobserver reproducibility was evaluated by calculating an intraclass correlation coefficient (ICC) in a mixed model. Each observer had a separate model using information from 5 scans. Interobserver variability was determined by Bland-Altman analysis. The ICC was calculated in a mixed model using a residual maximum likelihood method. The results of 3 and 5 repeated scans were evaluated to indicate the change to 1 measurement application. RESULTS: The mean anterior chamber angle measurement was 35.9 degrees +/- 5.7 (SD) for observer A and 36.2 +/- 5.7 degrees for observer B. The ICC was 0.94 and 0.91, respectively. The mean opening width was 315 +/- 62 microm for observer A and 317 +/- 60 microm for observer B. The ICC was 0.97 and 0.93, respectively. Interobserver comparisons showed a mean difference between anterior chamber angle measurements of -0.27 +/- 1.6 degrees, a limit of agreement (LOA) interval from -3.52 to 2.98 degrees, and an ICC estimate of 0.96. The mean difference in opening width measurements was 2.40 +/- 12.40 microm, the LOA from -27.20 to 22.40 microm, and the estimated ICC 0.96. Using 1 instead of the mean of 5 measurements, the LOA range increased by 3.46 degrees for the anterior chamber angle and 30.0 microm for the opening width. CONCLUSION: Anterior chamber angle and opening width measurements by OCT showed low intraobserver and interobserver variability, indicating OCT is a valuable technique for quantitative assessment that provides reproducible measurements and objective documentation by different examiners.     

Measuring the effect of interprofessional problem-based learning on the attitudes of undergraduate health care students

OBJECTIVES: This study aimed to measure the improvement in attitudes towards interprofessional collaboration of undergraduate health care students who have a single module of interprofessional problem-based learning (PBL) using real patients as triggers integrated into their curricula. DESIGN: A dedicated module, consisting of 5 PBL seminars, was integrated into the undergraduate medical, nursing and physiotherapy curricula at the participating institutions. Seminar groups consisted of students from a single profession in the control group, and of evenly distributed students from the participating professions in the intervention group. The Interdisciplinary Education Perception Scale was used to measure improvements in attitudes towards interprofessional co-operation. Patients, faculty members and students were included in the evaluation of the interprofessional module and their comments examined for indications of adverse effects of the use of patients in this setting. RESULTS: A total of 177 students were recruited into the study and assigned to 1 of 16 seminar groups, all of which attended the complete module, 8 in control mode and 8 in intervention mode. Statistically significant improvements could be identified in the overall attitudes of male students in the intervention group, and in attitudes pertaining to the competence and autonomy of individuals in one's own profession in the intervention group as a whole. No significant improvements were detected in the control group. No adverse effects of the use of real patients came to light. CONCLUSIONS: The integration of an interprofessional educational module that requires limited student and faculty time in undergraduate health care curricula may be proven to have an effect. The Interdisciplinary Education Perception Scale may be suitable for measuring such effect. Real patients may continue to contribute to education in this setting.     

Is there an indication for high-dose chemotherapy in the treatment of bone and soft-tissue sarcoma?

Sarcomas represent a rare and heterogeneous disease, and the prognosis of patients with unresectable or advanced metastatic bone and especially soft-tissue sarcomas remains poor, with a disease-free survival of less than 10% at 5 years. Only few chemotherapeutic agents have been identified to be active, with reported response rates for doxorubicin, epirubicin and ifosfamide above 20%. Although combination therapy with different chemotherapeutic substances results in higher response rates, superiority against single-agent chemotherapy in terms of survival has not been demonstrated yet. Regarding anthracyclines, and ifosfamide in particular, a dose-response relationship has been shown, and high-dose chemotherapy with stem cell support has also been evaluated by several investigators. However, all studies comprised small patient cohorts and included very heterogeneous histological subtypes of soft-tissue sarcoma. Moreover, randomized trials are missing. Nevertheless, higher doses of chemotherapy result in higher response rates possibly correlating with longer survival. Finally, well-designed randomized trials should be performed, preferably in younger patients and in the context of an interdisciplinary treatment approach. In this review, we provide an overview of the literature concerning high-dose chemotherapy with hematopoietic stem cell support in the treatment of bone and soft-tissue sarcomas. On the basis of our own data, we would like to emphasize the importance of high-dose chemotherapy in the treatment of sarcomas.     

成人高风险性软组织肉瘤的多形性治疗

Objective： We enrolled retrospective data to determine the efficacy of combined chemotherapy and surgery for local tumour control and survival in patients with high-risk soft-tissue sarcomas. Methods： We collected data from 25 patients with high-risk soft-tissue sarcomas treated with four cycles of etoposide, ifosfamide and doxorubicin （EIA） followed by definitive surgery with or without postoperative radiotherapy and adjuvant chemotherapy. 21 patients received chemotherapy in a neoadjuvant/adjuvant clinical setting; eighteen of them completed adjuvant chemotherapy. Four patients received chemotherapy in an adjuvant setting only. Results： The objective response rate of neoadjuvant chemotherapy assessable in 21 patients was 43%. Including NED （n=7） and partial remissions （n=3）, the radiographic response rate was 47.6% with additional 42.9% stable diseases （n=9）. Surgery was performed in two patients before completing four neoadjuvant chemotherapy cycles because of disease progression. Median overall survival for all patients was 21.6＋ months. After completion of chemotherapy, in 62% of patients R0-resection could be performed. Conclusion： High proportion of R0-resections supports the idea of tumour down-staging after neoadjuvant treatment. Response to neoadjuvant chemotherapy is predictive for improved local tumour control resulting in long-term survival benefit.     

A multitude of suppressors of group II intron-splicing defects in yeast

Disruption of the nuclear MRS2 gene (mrs2-1 mutation) causes a strong pet^- phenotype in strains with mitochondrial group II introns, and a leaky pet^- phenotype in strains without group II introns. MRS3 and MRS4, the genes for two mitochondrial-solute carrier proteins, can suppress both phenotypes when present in high-copy-number plasmids. In order to search for further multicopy suppressors of the mrs2-1 mutant phenotype, an yeast genomic DNA library, MW90, was constructed in YEp351 from a strain deleted for the MRS2, MRS3 and MRS4 genes. Ten different Sau3A DNA fragments that act as multicopy suppressors of the mrs2-1 respiratory-deficient phenotype were isolated from this library. Some of the newly isolated genes suppress the pet^- phenotypes of mrs2-1 cells in strains with and without mitochondrial group II introns. Other genes, however, are suppressors only for the mitochondrial intron-less strains. This supports the notion that the MRS2 gene product is bifunctional i.e., it is essential for the splicing of group II introns and is also involved in processes of mitochondrial biogenesis other than RNA splicing.     

Stem cell dose and tumorbiologic parameters as prognostic markers for patients with metastatic breast cancer undergoing high-dose chemotherapy with autologous blood stem cell support.

We report on the prognostic significance of tumorbiologic parameters and CD34(+) cell dose in 120 patients with metastatic breast cancer (MBC) who received high-dose chemotherapy (HDCT) with autologous blood stem cell transplantation as first-line treatment. Her2/neu, p53, Ki67, and bcl-2 protein expression were studied using immunohistochemical staining on formalin-fixed, paraffin-embedded primary tumor sections. DNA content of tumor cells (DNA-index) and tumor cell proliferation (S-phase fraction) were measured by DNA flow cytometry. The relationship between these parameters and the CD34(+) cell dose and progression free (PFS) and overall survival (OS) was analyzed. With a median follow-up period of 40 months (range, 7-89 months), no more than two metastatic sites (relative risk [RR] = 3.84 [95% confidence interval (CI) 1.49-10]; p =.005) and hyperploidy (RR = 2.58 [95% CI 1.26-5.26]; p =.009) were independent predictors of longer PFS according to multivariate analysis. Independent prognostic factors of longer OS included one or two metastatic sites (RR = 4.16 [95% CI 1.96-4.16]; p <.001), a positive combined hormone receptor status (RR = 2.45 [95% CI 1.45-4.14]; p =.001) and a high number of infused stem cells (>7.8 x 10(6) CD34(+) cells per kg body weight) (RR = 2.0 [95% CI 1.17-3.42]; p =.01). In conclusion, positive hormone receptors, < or =2 metastatic sites, high DNA-index and high CD34(+) cell dose (>7.8 x 10(6) CD34(+) cells per kg) are predictors for a favorable outcome after autotransplantation for MBC. Our observation might indicate a favorable effect of HDCT in MBC patients with overexpression of Her2/neu who might have a worse prognosis when treated with conventional chemotherapy.