Muonium addition reactions in the gas phase: Quantum tunneling in Mu + C2H4 and Mu + C2D4

Copyright © 1990 American Institute of Physics.The reaction kinetics for the addition of the muonium (Mu=μ+e−) atom to C2H4 and C2D4 have been measured over the temperature range 150–500 K at (N2) moderator pressures near 1 atm. A factor of about 8 variation in moderator pressure was carried out for C2H4, with no significant change seen in the apparent rate constant kapp, which is therefore taken to be at the high pressure limit, yielding the bimolecular rate constant kMu for the addition step. This is also expected from the nature of the μSR technique employed, which, in favorable cases, gives kapp=kMu at any pressure. Comparisons with the H atom data of Lightfoot and Pilling, and Sugawara et al. and the D atom data of Sugawara et al. reveal large isotope effects. Only at the highest temperatures, near 500 K, is kMu/kH given by its classical value of 2.9, from the mean velocity dependence of the collision rate but at the lowest temperatures kMu/kH≳30/1 is seen, reflecting the pronounced tunneling of the much lighter Mu atom (mμ=1/9 mp). The present Mu results should provide accurate tests of reaction theories on currently available ab initio surfaces.NSERC (Canada), the Canada Council for their awarding of a Killam Research Fellowship and the Meson Science Institute, Faculty of Science, University of Tokyo

The Grounds and Extent of Legal Responsibility

To question that is the title of this symposium, What Do Compensatory Damages Compensate?, requires consideration of the basic grounds and purposes of legal responsibility. The question is usefully brought into sharper focus by the specific questions and puzzles posed to the contributors to stimulate thought and discussion

National Mesothelioma Virtual Bank: A standard based biospecimen and clinical data resource to enhance translational research

Background: Advances in translational research have led to the need for well characterized biospecimens for research. The National Mesothelioma Virtual Bank is an initiative which collects annotated datasets relevant to human mesothelioma to develop an enterprising biospecimen resource to fulfill researchers' need. Methods: The National Mesothelioma Virtual Bank architecture is based on three major components: (a) common data elements (based on College of American Pathologists protocol and National North American Association of Central Cancer Registries standards), (b) clinical and epidemiologic data annotation, and (c) data query tools. These tools work interoperably to standardize the entire process of annotation. The National Mesothelioma Virtual Bank tool is based upon the caTISSUE Clinical Annotation Engine, developed by the University of Pittsburgh in cooperation with the Cancer Biomedical Informatics Grid™ (caBIG™, see http://cabig.nci.nih.gov). This application provides a web-based system for annotating, importing and searching mesothelioma cases. The underlying information model is constructed utilizing Unified Modeling Language class diagrams, hierarchical relationships and Enterprise Architect software. Result: The database provides researchers real-time access to richly annotated specimens and integral information related to mesothelioma. The data disclosed is tightly regulated depending upon users' authorization and depending on the participating institute that is amenable to the local Institutional Review Board and regulation committee reviews. Conclusion: The National Mesothelioma Virtual Bank currently has over 600 annotated cases available for researchers that include paraffin embedded tissues, tissue microarrays, serum and genomic DNA. The National Mesothelioma Virtual Bank is a virtual biospecimen registry with robust translational biomedical informatics support to facilitate basic science, clinical, and translational research. Furthermore, it protects patient privacy by disclosing only de-identified datasets to assure that biospecimens can be made accessible to researchers. © 2008 Amin et al; licensee BioMed Central Ltd

Should tumor depth be included in prognostication of soft tissue sarcoma?

BACKGROUND: Most staging systems for soft tissue sarcoma are based on histologic malignancy-grade, tumor size and tumor depth. These factors are generally dichotomized, size at 5 cm. We believe it is unlikely that tumor depth per se should influence a tumor's metastatic capability. Therefore we hypothesized that the unfavourable prognostic importance of depth could be explained by the close association between size and depth, deep-seated tumors on average being larger than the superficial ones. When tumor size is dichotomized, this effect should be most pronounced in the large size (>5 cm) group in which the size span is larger. METHODS: We analyzed the associations between tumor size and depth and the prognostic importance of grade, size and depth in a population-based series of 490 adult patients with soft tissue sarcoma of the extremity or trunk wall with complete, 4.5 years minimum, follow-up. RESULTS: Multivariate analysis showed no major prognostic effect of tumor depth when grade and size were taken into account. The mean size of small tumors was the same whether superficial or deep but the mean size of large and deep-seated tumors were one third larger than that of large but superficial tumors. Tumor depth influenced the prognosis in the subset of high-grade and large tumors. In this subset deep-seated tumors had poorer survival rate than superficial tumors, which could be explained by the larger mean size of the deep-seated tumors. CONCLUSION: Most of the prognostic value of tumor depth in soft tissue sarcomas of the extremity or trunk wall can be explained by the association between tumor size and depth

Association between the c.*229C>T polymorphism of the topoisomerase IIb binding protein 1 (TopBP1) gene and breast cancer

Topoisomerase IIb binding protein 1 (TopBP1) is involved in cell survival, DNA replication, DNA damage repair and cell cycle checkpoint control. The biological function of TopBP1 and its close relation with BRCA1 prompted us to investigate whether alterations in the TopBP1 gene can influence the risk of breast cancer. The aim of this study was to examine the association between five polymorphisms (rs185903567, rs116645643, rs115160714, rs116195487, and rs112843513) located in the 30UTR region of the TopBP1 gene and breast cancer risk as well as allele-specific gene expression. Five hundred thirty-four breast cancer patients and 556 population controls were genotyped for these SNPs. Allele-specific Top- BP1 mRNA and protein expressions were determined by using real time PCR and western blotting methods, respectively. Only one SNP (rs115160714) showed an association with breast cancer. Compared to homozygous common allele carriers, heterozygous and homozygous for the T variant had significantly increased risk of breast cancer (adjusted odds ratio = 3.81, 95 % confidence interval: 1.63–8.34, p = 0.001). Mean TopBP1 mRNA and protein expression were higher in the individuals with the CT or TT genotype. There was a significant association between the rs115160714 and tumor grade and stage. Most carriers of minor allele had a high grade (G3) tumors classified as T2-T4N1M0. Our study raises a possibility that a genetic variation of TopBP1 may be implicated in the etiology of breast cancer

The development of common data elements for a multi-institute prostate cancer tissue bank: The Cooperative Prostate Cancer Tissue Resource (CPCTR) experience

BACKGROUND: The Cooperative Prostate Cancer Tissue Resource (CPCTR) is a consortium of four geographically dispersed institutions that are funded by the U.S. National Cancer Institute (NCI) to provide clinically annotated prostate cancer tissue samples to researchers. To facilitate this effort, it was critical to arrive at agreed upon common data elements (CDEs) that could be used to collect demographic, pathologic, treatment and clinical outcome data. METHODS: The CPCTR investigators convened a CDE curation subcommittee to develop and implement CDEs for the annotation of collected prostate tissues. The draft CDEs were refined and progressively annotated to make them ISO 11179 compliant. The CDEs were implemented in the CPCTR database and tested using software query tools developed by the investigators. RESULTS: By collaborative consensus the CPCTR CDE subcommittee developed 145 data elements to annotate the tissue samples collected. These included for each case: 1) demographic data, 2) clinical history, 3) pathology specimen level elements to describe the staging, grading and other characteristics of individual surgical pathology cases, 4) tissue block level annotation critical to managing a virtual inventory of cases and facilitating case selection, and 5) clinical outcome data including treatment, recurrence and vital status. These elements have been used successfully to respond to over 60 requests by end-users for tissue, including paraffin blocks from cases with 5 to 10 years of follow up, tissue microarrays (TMAs), as well as frozen tissue collected prospectively for genomic profiling and genetic studies. The CPCTR CDEs have been fully implemented in two major tissue banks and have been shared with dozens of other tissue banking efforts. CONCLUSION: The freely available CDEs developed by the CPCTR are robust, based on "best practices" for tissue resources, and are ISO 11179 compliant. The process for CDE development described in this manuscript provides a framework model for other organ sites and has been used as a model for breast and melanoma tissue banking efforts

Radiological staging in breast cancer: which asymptomatic patients to image and how.

BACKGROUND: Approximately 4% of patients diagnosed with early breast cancer have occult metastases at presentation. Current national and international guidelines lack consensus on whom to image and how. METHODS: We assessed practice in baseline radiological staging against local guidelines for asymptomatic newly diagnosed breast cancer patients presenting to the Cambridge Breast Unit over a 9-year period. RESULTS: A total of 2612 patients were eligible for analysis; 91.7% were appropriately investigated. However in the subset of lymph node negative stage II patients, only 269 out of 354 (76.0%) investigations were appropriate. No patients with stage 0 or I disease had metastases; only two patients (0.3%) with stage II and or =4 positive lymph nodes), III and IV disease, respectively. CONCLUSION: These results prompted us to propose new local guidelines for staging asymptomatic breast cancer patients: only clinical stage III or IV patients require baseline investigation. The high specificity and convenience of computed tomography (chest, abdomen and pelvis) led us to recommend this as the investigation of choice in breast cancer patients requiring radiological staging

Optimization of total protein and activity assays for the detection of MMP-12 in induced human sputum

<p>Abstract</p> <p>Background</p> <p>Proteolysis of matrix components, in particular elastin, is a major contributing factor to the development of lung diseases such as emphysema and chronic obstructive pulmonary disease (COPD). MMP-12 (macrophage elastase) is a protease known to be involved in the progression of lung disease. The relatively low abundance of MMP-12 has precluded the development of quantitative assays that can accurately measure MMP-12 protein levels and activity across cohorts of healthy and diseased individuals.</p> <p>Methods</p> <p>Commercial antibodies were screened for performance in sandwich ELISA and capture FRET activity assay formats. Precision, accuracy, sensitivity, dilution linearity, and spike recovery were evaluated using sputum samples.</p> <p>Results</p> <p>Total protein and capture FRET activity assays were developed that were sensitive enough to detect MMP-12 in 37 of 38 donor sputum samples. A comparison of results between the two assays shows that a majority of sputum MMP-12 is in the active form. No differences were seen between normal, asthmatic, and COPD donors.</p> <p>Conclusion</p> <p>Sensitive and quantitative assays for both MMP-12 activity and total protein in human induced sputum have been developed. These assays can be used to evaluate MMP-12 as a biomarker for lung disease, and to monitor efficacy of potential therapeutic compounds.</p

Sequential chemotherapy and intensity-modulated radiation therapy in the management of locoregionally advanced nasopharyngeal carcinoma: Experience of 370 consecutive cases

<p>Abstract</p> <p>Introduction</p> <p>To investigate the outcome of locoregionally advanced nasopharyngeal carcinoma (NPC) treated with intensity-modulated radiation therapy (IMRT) after induction chemotherapy, with or without concomitant chemotherapy.</p> <p>Methods</p> <p>Between August 2003 and March 2007, 370 patients with locoregionally advanced NPC were treated with IMRT. Presenting stages were stage IIB in 62, stage III in 197, and stage IVA/B in 111 patients. All patients except for 36 patients with cervical lymphadenopathy of 4 cm or less in diameter received 2 cycles of cisplatin-based neoadjuvant chemotherapy. Forty-eight patients received cisplatin-based concurrent chemotherapy as well.</p> <p>Results</p> <p>With a median follow-up time of 31 months (range 5 to 61 months), the 3-year local control, regional control, metastasis-free survival (MFS), disease-free survival (DFS) and overall survival (OS) rates were 95%, 97%, 86%, 81% and 89%, respectively. Multivariate analyses revealed that both age (≤ 60 vs. >60) and N-classification are significant prognosticators for OS (P = 0.001, hazard ratio [HR] 2.395, 95% confidence interval [CI] 1.432-4.003; P = 0.012, hazard ratio [HR] 2.614, 95% confidence interval [CI] 1.235-5.533); And N-classification is the only significant predicative factor for MFS (P = 0.002, [HR] 1.99, 95% CI 1.279-3.098). T-classification and concurrent chemotherapy were not significant prognostic factors for local/regional control, MFS, DFS, or OS. Subgroup analysis revealed that concurrent chemotherapy provided no significant benefit to IMRT in locoregionally advanced NPC, but was responsible for higher rates of grade 3 or 4 acute toxicities (50% vs. 29.8%, P < 0.005). No grade 3 or 4 late toxicity including xerostomia was observed. However, two patients treated with IMRT and neoadjuvant but without concurrent and adjuvant chemotherapy died of treatment related complications.</p> <p>Conclusion</p> <p>IMRT following neoadjuvant chemotherapy produced a superb outcome in terms of local control, regional control, MFS, DFS, and OS rates in patients with stage IIB to IVB NPC. Effective treatment strategy is urgently needed for distant control in patients diagnosed with locoregionally advanced NPC.</p