Activation of K-RAS by co-mutation of codons 19 and 20 is transforming.

The K-RAS oncogene is widely mutated in human cancers. Activating mutations in K-RAS give rise to constitutive signalling through the MAPK/ERK and PI3K/AKT pathways promoting increased cell division, reduced apoptosis and transformation. The majority of activating mutations in K-RAS are located in codons 12 and 13. In a human colorectal cancer we identified a novel K-RAS co-mutation that altered codons 19 and 20 resulting in transitions at both codons (L19F/T20A) in the same allele. Using focus forming transformation assays in vitro , we showed that co-mutation of L19F/T20A in K-RAS demonstrated intermediate transforming ability that was greater than that of individual L19F and T20A mutants, but less than that of G12D and G12V K-RAS mutants. This demonstrated the synergistic effects of co-mutation of codons 19 and 20 and illustrated that co-mutation of these codons is functionally significant.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are

Human papillomavirus type 18 is associated with less apoptosis in fibroblast tumours than human papillomavirus type 16.

In human cervical neoplasia human papillomavirus (HPV) type 18 has a higher cancer/cervical intraepithelial neoplasia (CIN) prevalence ratio than HPV 16. Fibrosarcomas derived from rat fibroblasts transfected with HPV 16 or 18 genomes showed increased apoptosis compared with controls. However, HPV 18 was associated with significantly less apoptosis than HPV 16, affording one possible explanation for the more rapidly progressive cervical neoplasia associated with HPV 18

A Micro-Raman Spectroscopic Study of Hydrazine-Treated Human Dental Calculus

Hydrazine has been used to remove organic components and to isolate the mineral(s) from human calculus. Micro-Raman measurements were performed on the mineral phase. After the hydrazine-treatment, not only a large reduction in fluorescence but also an increase in Raman signal was observed. The treatment was essential in minimizing thermally-induced chemical changes which could otherwise occur to the original calculus mineral due to the intense laser light. The Raman spectral features of the mineral were nearly all identical among the Raman spectra obtained at many randomly-selected sites by the micro-Raman microbe with a lateral resolution of approximately 1 μm, and were consistent with those of impure hydroxyapatite containing CO32- and HPO42-. The spectra contained typical hydroxyapatite bands including PO43- bands of the v1, v2, v3 and v4 modes and one OH- stretch band. Other minor bands due to the CO32- v1 and v3 modes and bands possibly due to the HPO42- v1, v2 and v4 modes were observable by the technique despite the hydrazine-treatment that could in principle remove the HPO4 and CO3 ions from the mineral. In comparison with pure synthetic hydroxyapatite, the intensity of the OH- stretch band relative to that of the PO43- v1 band was approximately 70% weaker, and the bandwidth of the phosphate v1 band was 200% broader, reflecting various crystal imperfections presumably present in the calculus mineral

Susceptibility to apoptosis is differentially regulated by c-myc and mutated Ha-ras oncogenes and is associated with endonuclease availability.

Oncogenes and oncosuppressors can deregulate cell replication in tumours, and recently have been shown to influence the probability of apoptosis. The effects of human c-myc and mutated (T24) Ha-ras oncogenes on susceptibility to apoptosis were investigated by introducing them into immortalised rat fibroblasts. The resulting family of transfectants showed closely similar measures of proliferation, but widely divergent rates of apoptosis, differing by up to fifteen-fold, that correlated inversely with population expansion rates in vitro. T24-ras transfectants with moderate or high p21ras expression showed reduced apoptosis, and this was reversed by pharmacological inhibition of membrane localisation of p21ras by mevinolin. In contrast, c-myc stimulated apoptosis, and this was further enhanced by serum deprivation. Inducibility of effector proteins represents one possible mechanism of genetic control of the susceptibility to apoptosis, and its investigation showed that c-myc was associated with expression by viable cells of latent calcium/magnesium sensitive endonuclease activity characteristic of apoptosis. In contrast, endonuclease activity was not detected in viable cells of a T24-ras transfectant expressing high levels of p21ras. Thus, there appeared to be differential regulation of susceptibility to apoptosis, positively by c-myc and negatively by activated ras, and this was associated with availability of endonuclease activity. Genetic modulation of apoptosis in human neoplasms is likely to influence net growth rate, retention of cells acquiring new mutations and response to certain chemotherapeutic agents

The Gerasimov-Drell-Hearn Sum Rule and the Spin Structure of the Nucleon

The Gerasimov-Drell-Hearn sum rule is one of several dispersive sum rules that connect the Compton scattering amplitudes to the inclusive photoproduction cross sections of the target under investigation. Being based on such universal principles as causality, unitarity, and gauge invariance, these sum rules provide a unique testing ground to study the internal degrees of freedom that hold the system together. The present article reviews these sum rules for the spin-dependent cross sections of the nucleon by presenting an overview of recent experiments and theoretical approaches. The generalization from real to virtual photons provides a microscope of variable resolution: At small virtuality of the photon, the data sample information about the long range phenomena, which are described by effective degrees of freedom (Goldstone bosons and collective resonances), whereas the primary degrees of freedom (quarks and gluons) become visible at the larger virtualities. Through a rich body of new data and several theoretical developments, a unified picture of virtual Compton scattering emerges, which ranges from coherent to incoherent processes, and from the generalized spin polarizabilities on the low-energy side to higher twist effects in deep inelastic lepton scattering.Comment: 32 pages, 19 figures, review articl

Pulmonary involvement in primary Sjogren's syndrome, as measured by the ESSDAI

Objective: Systemic features influence disease prognosis and choice of treatment in primary Sjogren's syndrome (pSS). Our aim was to investigate the prevalence of pulmonary involvement in pSS patients and to classify patients according to the pulmonary domain of the EULAR Sjogren's Syndrome Disease Activity Index (ESSDAI). Methods: This retrospective cohort study included consecutive pSS patients, fulfilling American-European Consensus Group/American College of Rheumatology classification criteria, who visited the Department of Rheumatology and Clinical Immunology, University Medical Center Groningen, in 2015. Data on pulmonary complaints and pulmonary tests were obtained from electronic patient records. Pulmonary involvement was recorded if therapy was needed or follow-up was recommended, and when it was possibly or assumed to be related to pSS instead of coincidental factors. Results: Of the 262 included pSS patients, 88 (34%) had pulmonary complaints, mostly cough or dyspnoea on exertion. Pulmonary diagnostics were performed in 225 patients (86%). Pulmonary involvement was present and assumed to be related to pSS in 25 patients (10%) and possibly related to pSS in 14 (5%). Interstitial lung disease (ILD, n = 15), especially non-specific interstitial pneumonia (n = 7), was present most commonly. In total, 16 patients (6%) were scored as low (n = 4), moderate (n = 11), or high activity (n = 1) on the ESSDAI pulmonary domain. Conclusion: In this cross-sectional study in daily clinical practice, pulmonary involvement was present in 10-15% of pSS patients, of which ILD was most common. Of all pSS patients, 6% were scored as active on the pulmonary domain of the ESSDAI

Development and performance of the Clinical Trials ESSDAI (ClinTrialsESSDAI), consisting of frequently active clinical domains, in two randomised controlled trials in primary Sjogren's syndrome

Objective. To develop and evaluate the Clinical Trials EULAR Sjogren's Syndrome Disease Activity Index (ClinTrialsESSDAI), consisting of frequently active clinical domains of the ESSDAI, using two randomised controlled trials in primary Sjogren's syndrome (pSS). Methods. The ASAP-III trial in abatacept (80 pSS patients) and TRACTISS trial in rituximab (133 pSS patients) were analysed. The most frequently active clinical domains were selected, and ClinTrialsESSDAI total score was calculated using existing weightings of the ClinESSDAI (which also excludes the biological domain). Performance of the ClinTrialsESSDAI was compared to ClinESSDAI and ESSDAI. Responsiveness was assessed using standardised response mean (SRM), and discrimination was assessed using adjusted mean difference. Results. Besides the biological domain, the most frequently active domains were glandular, articular, haematological, constitutional, lymphadenopathy and cutaneous. These domains were selected for the ClinTrialsESSDAI. At primary endpoint visits, SRM values of ClinTrialsESSDAI, ClinESSDAI and ESSDAI were respectively -0.65/-0.59, -0.63/-0.59 and - 0.64/-0.61 for abatacept/placebo and -0.33/-0.13, -0.34/0.12 and -0.41/-0.16 for rituximab/placebo. Adjusted mean differences between active treatment and placebo groups were respectively -1.7, -1.4 and -1.1 for ASAP-III and -1.1, -1.1 and -1.2 for TRACTISS. Conclusion. The ClinTrialsESSDAI, consisting of six frequently active clinical domains of the ESSDAI, shows closely similar responsiveness and discrimination between treatment groups compared to the ClinESSDAI and ESSDAI. Therefore, this ClinTrialsESSDAI is not preferable to ClinESSDAI and ESSDAI for use as primary endpoint. A composite endpoint combining response at multiple clinically relevant items seems more suitable as primary study endpoint in pSS