Phase II trial of oral gimatecan in adults with recurrent glioblastoma

2009

Background: Gimatecan is a highly lipophilic oral camptothecin analogue with impressive preclinical activity in glioma models. Methods: We conducted a multicenter two-stage phase II trial to evaluate the efficacy of gimatecan in adults with recurrent glioblastoma. Eligibility criteria included ≤1 prior treatment for recurrent disease, age ≥18, ECOG performance status 0 or 1, and normal organ function. Patients taking enzyme-inducing anti-seizure medications were excluded. Gimatecan 1.22 mg/m2 was given orally once daily for 5 consecutive days during each 28-day cycle. Radiographic response was evaluated by MRI after every second cycle. The primary endpoint of the study was 6 months PFS. A Simon's 2-stage design was used in which 19 patients were evaluated in the first stage, with an additional 36 patients accrued if > 4 patients in stage 1 achieved 6 month PFS. Results: A total of 29 patients were enrolled in the study, with median age of 58 years (range, 25–77 years); 58.6% female; all of whom had received prior surgery, radiation therapy, and at least one regimen of chemotherapy. The daily dose was reduced to 1.0 mg/m2 after four of the first 10 patients experienced grade 4 hematologic toxicity. One patient was removed from trial due to toxicity (grade 3 leukopenia and thrombocytopenia). Treatment delay occurred in 11 patients (38%) and dose reduction was necessary in eight patients (28%). Treatment-related grade 3/4 toxicities included thrombocytopenia (17.2%), leukopenia (17.2%), and neutropenia (10.3%). Only 1/19 patients treated with 1.0 mg/m2/day experienced grade 3/4 hematologic toxicity. The 18% reduction in the daily dose resulted in a 19% decrease in the concentration of total gimatecan in plasma prior to administration of the fifth daily dose (56 ± 23 vs. 45 ± 20 ng/mL) and a 33% decrease in the AUC for dose 5 (8.0±4.8 vs. 5.3±4.2 ng*h/mL). Only one patient had a partial radiographic response by the modified Macdonald criteria and stable disease was the best response in 13 patients. All other patients had progressive disease after two cycles of therapy. Only three patients (12%) were progression-free at 6 months. Median time to progression was 12.0 weeks (95% CI: 7.0, 17.0). Conclusions: Treatment with single-agent gimatecan 1.0 mg/m2/day for 5 days, repeated every 28-days showed minimal efficacy.

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Precise measurement of the neutron magnetic form factor G(M)n in the few-GeV2 region

The neutron elastic magnetic form factor was extracted from quasielastic electron scattering on deuterium over the range Q;{2}=1.0-4.8 GeV2 with the CLAS detector at Jefferson Lab. High precision was achieved with a ratio technique and a simultaneous in situ calibration of the neutron detection efficiency. Neutrons were detected with electromagnetic calorimeters and time-of-flight scintillators at two beam energies. The dipole parametrization gives a good description of the data.

Protective factors relating to decreased risks of adolescent suicidal behaviour

BACKGROUND

Suicide has been identified as one of the three leading causes of death in adolescents and young adults. No previous study in China has tested the association between protective factors and urban adolescents' suicidal behaviours. In this study we tested the hypothesis that suicidal behaviours would be associated with multiple protective factors.

METHODS

A stratified random of 9015 students from 100 junior middle schools in Beijing, Hangzhou, Wuhan and Urumqi completed the Chinese version of Global School-Based Student Health Survey.

RESULTS

Overall, 17.4% of students had seriously considered attempting suicide, and 8.1% had made a specific plan to attempt suicide during the 12 months preceding the survey. The students in Wuhan (18.7%) and Urumqi (20.8%) cities were significantly more likely than students in Beijing (14.4%) and Hangzhou (14.4%) to have suicidal ideation (chi2 = 45.9, P < 0.001). Female students were significantly more likely than male students to have suicidal ideation and have made suicide attempts [odds ratio (OR) = 1.4, P < 0.001]. Results indicated that the rates of suicidal ideation and suicide attempts increased with age (OR = 1.44, P < 0.001). Multivariate logistic regression models showed that suicide risk tended to decrease significantly when 'days of missed classes or school without permission were less than one', and when students thought students in their school were kind and helpful most of the time or always', 'parents or guardians checked to see if homework was done most of the time or always', 'parents or guardians understood their problems and worries most of the time or always' and 'parents or guardians really know what they are doing with their free time most of the time or always'.

CONCLUSIONS

Adolescent suicide behaviour should be a serious problem. Measures can be taken to prevent suicide by observing the factors significantly linked to suicidal behaviour. Steps can then be taken to identify adolescents who have serious suicidal ideation so that intervention can be taken to reduce the suicidal rate.

Identification of calcification with MRI using susceptibility-weighted imaging: a case study

Susceptibility weighted imaging (SWI) is a new MRI technique that can identify calcification by using phase images. We present a single case with a partially calcified oligodendroglioma, multiple calcified cysticercosis lesions, and multiple physiologic calcifications in the same patient. SWI phase images and computed tomography (CT) images are compared. SWI phase images showed the same calcified lesions as shown on CT and sometimes some new calcifications. Our conclusion is that SWI filtered phase images can identify calcifications as well as CT in this case.

Evaluation of effectiveness of chemical and physical sewage treatment technologies for removal of retinoic acid receptor agonistic activity detected in sewage effluent

Retinoic acid receptor (RAR) is a nuclear receptor involved in vertebrate morphogenesis, growth, cellular differentiation, and tissue homeostasis. Excess expression of the retinoid signaling can cause various developmental toxicities in animals and humans. We previously found that influents from sewage treatment plants (STPs) in Japan had a RAR agonistic activity and the activity cannot be removed completely by conventional biological treatments. In this study, we assessed the performance of chemical and physical sewage treatment technologies-ozonation, ultraviolet treatment, chlorination, coagulation using polyaluminium chloride (PAC) and ferric sulfate, and filtration with ultrafiltration (UF), nanofiltration (NF), and reverse osmosis (RO) membranes-in removal of RAR agonistic activity of STP effluent. All water treatment experiments were conducted in laboratory-scale reactors. The RAR agonistic activity of samples was measured using a yeast two-hybrid assay. Results showed that the effectiveness of tested technologies on the removal of RAR agonistic activity can be ranked as RO or NF > chlorination > ozonation > MF > UV > coagulation with ferric sulfate>>coagulation with PAC. Furthermore, the effectiveness of chlorination might rank lower because excess reaction might bring a side effect by producing some RAR agonistic by-product(s).

Meta- and pooled analyses of the effect of glutathione S-transferase M1 and T1 deficiency on chronic obstructive pulmonary disease

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a complex polygenic disease in which gene-environment interactions are very important. A number of studies have investigated the genotypes of glutathione S-transferase M1 and T1 (GSTM1 and GSTT1) in relation to COPD susceptibility in different populations. However, the results of individual studies have been inconsistent.

METHODS

To address the inconsistent findings in studies of the association of the polymorphism of the GSTM1 and GSTT1 genes with susceptibility to COPD, we performed a meta-analysis of the published data. We searched the Medline database for case-control studies published from 1966 to July 2008. Data were extracted and pooled, and ORs were calculated with their 95%CIs.

RESULTS

Twelve eligible studies comprising 1697 patients with COPD and 1867 controls were included in the meta-analysis. The pooled result showed that the GSTM1 deficiency was associated with risk of COPD (OR 1.46, 95%CI 1.16-1.83). Subgroup analysis supported the results in smoking and non-Asian populations, but not in Asian populations. The GSTT1 deficiency was not associated with risk of COPD.

CONCLUSIONS

The GSTM1 gene is a genetic contributor to overall COPD susceptibility in non-Asian populations, and the GSTT1 gene is not associated with COPD.

Disruption of Spodoptera exigua larval development by silencing chitin synthase gene A with RNA interference

RNA interference (RNAi) is a powerful tool for rapidly analyzing gene functions. However, little is known about the possible use of dsRNA/siRNA as a pest control method. Here, we demonstrate that dsRNA/siRNA can induce the silence of chitin synthase gene A (CHSA), which is an important gene for the growth and development of cuticles and trachea in beet armyworm, Spodoptera exigua. Based on the in vitro RNAi experiments in an insect cell line (Trichoplusia ni High 5), in vivo RNAi was performed by injecting synthesized dsRNA/siRNA into the 4th instar larvae of S. exigua. Significantly lower levels of CHSA transcripts were detected. In addition, the cuticle of these insects was disordered and the epithelial walls of larval trachea did not expand uniformly in injected individuals. Moreover, Injections significantly increased abnormalities relative to control larvae. These results highlighted the possibility of dsRNA/siRNA for gene function studies in lepidopteran insects and future pest control.

New measurement of the K+-->pi+ nunu branching ratio

Three events for the decay K+-->pi+ nunu have been observed in the pion momentum region below the K+-->pi+pi0 peak, 140 < Ppi < 199 MeV/c, with an estimated background of 0.93+/-0.17(stat.) -0.24+0.32(syst.) events. Combining this observation with previously reported results yields a branching ratio of B(K+-->pi+ nunu) = (1.73(-1.05)+1.15) x 10(-10) consistent with the standard model prediction.