Crizotinib in c-MET- or ROS1-positive NSCLC: results of the AcSé phase II trial.

BACKGROUND: In 2013, the French National Cancer Institute initiated the AcSé program to provide patients with secure access to targeted therapies outside of their marketed approvals. Efficacy and safety was then assessed using a two-stage Simon phase II trial design. When the study design was designed, crizotinib was approved only as monotherapy for adults with anaplastic lymphoma kinase plus non-small-cell lung cancers (NSCLC). PATIENTS AND METHODS: Advanced NSCLC patients with c-MET ≥6 copies, c-MET-mutated, or ROS-1-translocated tumours were enrolled in one of the three cohorts. Patients were treated with crizotinib 250 mg twice daily. Efficacy was assessed using the objective response rate (ORR) after two cycles of crizotinib as primary outcome. Secondary outcomes included disease control rate at four cycles, best ORR, progression-free survival, overall survival, and drug tolerance. RESULTS: From August 2013 to March 2018, 5606 patients had their tumour tested for crizotinib targeted molecular alterations: 252 patients had c-MET ≥6 copies, 74 c-MET-mutation, and 78 ROS-1-translocated tumour. Finally, 25 patients in the c-MET ≥6 copies cohort, 28 in the c-MET-mutation cohort, and 37 in the ROS-1-translocation cohort were treated in the phase II trial. The ORR was 16% in the c-MET ≥6 copies cohort, 10.7% in the mutated, and 47.2% in the ROS-1 cohort. The best ORR during treatment was 32% in the c-MET-≥6 copies cohort, 36% in the c-MET-mutated, and 69.4% in the ROS-1-translocation cohort. Safety data were consistent with that previously reported. CONCLUSIONS: Crizotinib activity in patients with ROS1-translocated tumours was confirmed. In the c-MET-mutation and c-MET ≥6 copies cohorts, despite insufficient ORR after two cycles of crizotinib, there are signs of late response not sufficient to justify the development of crizotinib in this indication. The continued targeting of c-MET with innovative therapies appears justified. CLINICAL TRIAL NUMBER: NCT02034981.

[Double J stent removal's cost estimate using a re-sterilizable fibroscope in a French private structure]. / Évaluation du coût en structure privée d'une ablation de sonde double J en externe à l'aide d'un fibroscope re-stérilisable.

In front of the arrival of new devices intended to simplify the removal of double J stent, it poses the problem of the knowledge of the real cost of such an ablation under the current conditions of realization. MATERIAL AND METHOD: This is a monocentric economic evaluation of cost and remuneration needed data-gathering of quotation (CCAM, GHS/SE, …), estimate of the associated costs of wear and damping of the endoscopic equipments (endoscopes, cables, …), estimate of the cost of sterilization, estimate of the associated costs to the intervention of staff (Auxiliary nurse [AS] and Nurse [IDE]) with timing of the various tasks. RESULTS: Quotation CCAM JCGE004 (48€) gives access to fixed price SE1 (73.71€ for private clinic, and 75.89€ for public institution) without hospitalization nor anaesthesia. The costs were reported to an act of single double J removal. Concerning the equipments: 4.42€HT for the fibroscopes, graspers, cable and light. The costs of sterilization were: 17.95€HT. The timed workforce's costs were: 7.61-9.51€ for AS and 9.92-10.84€ for IDE. The cost of consumable was about 1.37 €HT, by excluding the common base from the extractions (1.876€HT). The total costs in France in 2016 were thus about 47.4 to 50.496€ including all taxes. CONCLUSIONS: This estimate will be used certainly for reflection on the investments and the future studies of the economic impact of the new devices of extraction, by correlating it of course with the various maintenance contracts from each institution. LEVEL OF PROOF: 4.

Axillary lymph node micrometastases decrease triple-negative early breast cancer survival.

BACKGROUND: Triple-negative breast cancers (TNBCs) are the most deadly form of breast cancer (BC) subtypes. Axillary lymph node involvement (ALNI) has been described to be prognostic in BC taken as a whole, but its prognostic value in each subtype is unclear. We explored the prognostic impact of ALNI and especially of small size axillary metastases in early TNBCs. METHODS: We analysed in this multicentre study all patients treated for early TNBC in 12 French cancer centres. We explored the correlation between clinicopathological data and ALNI, with a specific focus on the dichotomisation between macrometastases and occult metastases, which is defined as the presence of isolated tumour cells or micrometastases. The prognostic value of ALNI both in terms of disease-free survival (DFS) and overall survival (OS) was also explored. RESULTS: We included 1237 TNBC patients. Five-year DFS and OS were 83.7% and 88.5%, respectively. The identified independent prognostic features for DFS were tumour size >20 mm (hazard ratio (HR)=1.86; 95% CI: 1.11-3.10, P=0.018), lymphovascular invasion (HR=1.69; 95% CI: 1.21-2.34, P=0.002) and ALNI both in case of macrometastases (HR=1.97; 95% CI: 1.38-2.81, P<0.0001) and occult metastases (HR=1.72; 95% CI: 1.1-2.71, P=0.019). DFS and OS were similar between tumours with occult metastases and macrometastases. Tumours presenting at least two pejorative features (out of ALNI, lymphovascular invasion and large tumour size) displayed a significantly poorer DFS in both the training set and validation set, independently of chemotherapy administration. Tumours with no more than one of the above-cited pejorative features had a 5-year OS of ⩾90% vs 70% for other cases (P<0.0001). CONCLUSIONS: Axillary lymph node involvement is a key prognostic feature for early TNBC when isolated tumour cells were identified in lymph nodes. This impact is independent of chemotherapy use.

Immunohistochemical subtypes predict the clinical outcome in high-risk node-negative breast cancer patients treated with adjuvant FEC regimen: results of a single-center retrospective study.

BACKGROUND: Anthracycline-based adjuvant chemotherapy improves survival in patients with high-risk node-negative breast cancer (BC). In this setting, prognostic factors predicting for treatment failure might help selecting among the different available cytotoxic combinations. METHODS: Between 1998 and 2008, 757 consecutive patients with node-negative BC treated in our institution with adjuvant FEC (5FU, epirubicin, cyclophosphamide) chemotherapy were identified. Data collection included demographic, clinico-pathological characteristics and treatment information. Molecular subtypes were derived from estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2) status and Scarff-Bloom-Richardson (SBR) grade. Disease-free survival (DFS), distant disease-free survival (DDFS) and overall survival (OS) were estimated using the Kaplan-Meier Method, and prognostic factors were examined by multivariate Cox analysis. RESULTS: After a median follow-up of 70 months, the 5-year DFS, DDFS and OS were 90.6 % (95 % confidence interval (CI): 88.2-93.1), 92.8 % (95 % CI: 90.7-95) and 95.1 % (95 % CI, 93.3-96.9), respectively. In the multivariate analysis including classical clinico-pathological parameters, only grade 3 maintained a significant and independent adverse prognostic impact. In an alternative multivariate model where ER, PR and grade were replaced by molecular subtypes, only luminal B/HER2-negative and triple-negative subtypes were associated with reduced DFS and DDFS. CONCLUSIONS: Node-negative BC patients receiving adjuvant FEC regimen have a favorable outcome. Luminal B/HER2-negative and triple-negative subtypes identify patients with a higher risk of treatment failure, which might warrant more aggressive systemic treatment.

Could thyroid dysfunction influence outcome in sunitinib-treated metastatic renal cell carcinoma?

BACKGROUND: Sunitinib is a standard of care for metastatic renal cell carcinoma (mRCC). Hypothyroidism is frequently observed under sunitinib therapy. This study was conducted to prospectively determine the correlation between thyroid function and progression-free survival (PFS) in this population. PATIENTS AND METHODS: One hundred and eleven mRCC patients treated with sunitinib were evaluated for serum thyroid-stimulating hormone (TSH) and T4 levels before treatment and every 6 weeks during treatment. Survival was analysed according to a landmark method with a cut-off of 6 months, excluding early progressive or early-censored patients. RESULTS: Out of the 102 patients with normal baseline thyroid function, 53% developed thyroid dysfunction, including 95% hypothyroidisms out of which 90.9% received L-thyroxine replacement. Median time to TSH alteration was 5.4 months. Median PFS was 11.7 months for the entire population. Median PFS was not different between the groups with abnormal or normal thyroid function after 6 months of treatment (18.9 and 15.9 months, respectively, log-rank P = 0.94, hazard ratio = 1.02, 95% confidence interval = 0.54-1.93). There was no difference even after adjustment for Memorial Sloan-Kettering Cancer Centre classification and therapy line. CONCLUSIONS: Abnormal thyroid function with hormonal substitution did not increase survival in our population, independent of initial prognosis and previous treatments. Larger comparative studies are deserved to validate these conclusions.

A seven-gene prognostic model for platinum-treated ovarian carcinomas.

BACKGROUND: Prognosis of ovarian carcinoma is poor, heterogeneous, and not accurately predicted by histoclinical features. We analysed gene expression profiles of ovarian carcinomas to identify a multigene expression model associated with survival after platinum-based therapy. METHODS: Data from 401 ovarian carcinoma samples were analysed. The learning set included 35 cases profiled using whole-genome DNA chips. The validation set included 366 cases from five independent public data sets. RESULTS: Whole-genome unsupervised analysis could not distinguish poor from good prognosis samples. By supervised analysis, we built a seven-gene optimal prognostic model (OPM) out of 94 genes identified as associated with progression-free survival. Using the OPM, we could classify patients in two groups with different overall survival (OS) not only in the learning set, but also in the validation set. Five-year OS was 57 and 27% for the predicted 'Favourable' and 'Unfavourable' classes, respectively. In multivariate analysis, the OPM outperformed the individual current prognostic factors, both in the learning and the validation sets, and added independent prognostic information. CONCLUSION: We defined a seven-gene model associated with outcome in 401 ovarian carcinomas. Prospective studies are warranted to confirm its prognostic value, and explore its potential ability for better tailoring systemic therapies in advanced-stage tumours.

Did the introduction of maize into Europe provide enemy-free space to Ostrinia nubilalis? Parasitism differences between two sibling species of the genus Ostrinia.

We examined whether maize offers enemy-free space (EFS) to its pest Ostrinia nubilalis, and may thereby have contributed to its divergence from the sibling species, Ostrinia scapulalis, feeding mainly on mugwort, when introduced into Europe five centuries ago. We collected Ostrinia larvae on maize (70 populations, 8425 individuals) and mugwort (10 populations, 1184 individuals) and recorded parasitism using both traditional (counting emerging parasitoids) and molecular methods (detection by specific polymerase chain reaction). The main parasitoid was Macrocentrus cingulum (Braconidae). On mugwort, parasitism was twice that on maize, and parasitoid-related mortality was 8 times higher. This suggests that maize affords substantial EFS to Ostrinia feeding on it. The lower Mortality:Infestation ratio in maize suggests that O. nubilalis' immune response might be stronger than that of O. scapulalis. If so, adapting to maize and diverging from O. scapulalis would decrease the impact of parasitism on O. nubilalis at both ecological and evolutionary levels.

Review: Associations among goods, impacts and ecosystem services provided by livestock farming.

Livestock is a major driver in most rural landscapes and economics, but it also polarises debate over its environmental impacts, animal welfare and human health. Conversely, the various services that livestock farming systems provide to society are often overlooked and have rarely been quantified. The aim of analysing bundles of services is to chart the coexistence and interactions between the various services and impacts provided by livestock farming, and to identify sets of ecosystem services (ES) that appear together repeatedly across sites and through time. We review three types of approaches that analyse associations among impacts and services from local to global scales: (i) detecting ES associations at system or landscape scale, (ii) identifying and mapping bundles of ES and impacts and (iii) exploring potential drivers using prospective scenarios. At a local scale, farming practices interact with landscape heterogeneity in a multi-scale process to shape grassland biodiversity and ES. Production and various ES provided by grasslands to farmers, such as soil fertility, biological regulations and erosion control, benefit to some extent from the functional diversity of grassland species, and length of pasture phase in the crop rotation. Mapping ES from the landscape up to the EU-wide scale reveals a frequent trade-off between livestock production on one side and regulating and cultural services on the other. Maps allow the identification of target areas with higher ecological value or greater sensitivity to risks. Using two key factors (livestock density and the proportion of permanent grassland within utilised agricultural area), we identified six types of European livestock production areas characterised by contrasted bundles of services and impacts. Livestock management also appeared to be a key driver of bundles of services in prospective scenarios. These scenarios simulate a breakaway from current production, legislation (e.g. the use of food waste to fatten pigs) and consumption trends (e.g. halving animal protein consumption across Europe). Overall, strategies that combine a reduction of inputs, of the use of crops from arable land to feed livestock, of food waste and of meat consumption deliver a more sustainable food future. Livestock as part of this sustainable future requires further enhancement, quantification and communication of the services provided by livestock farming to society, which calls for the following: (i) a better targeting of public support, (ii) more precise quantification of bundles of services and (iii) better information to consumers and assessment of their willingness to pay for these services.

Modelling interacting plant and livestock renewal dynamics helps disentangle equilibrium and nonequilibrium aspects in a Mongolian pastoral system.

The interplay of livestock density dependence drivers and climate hazards is thought to cause pasture deterioration and poverty in Mongolian pastoral systems. We assessed their relative weights in a system of the Gobi exposed to high rainfall variability and harsh winters, which suggests that climate is the main system's driver. In this aim we modelled how interacting plant and livestock renewal dynamics impact herder performances, under the influence of climate. Plant dynamics was studied through an underground biomass sub-model because local pastures are dominated by perennial species. This approach enabled us studying pastoral issues in a holistic way, by integrating plant underground organs, livestock populations, herder income, and climate drivers. Models described that current grazing practices can significantly reduce underground biomass (-30% after 20years), but not entirely deplete it. They also showed that competition between herders could trap the smallest ones in poverty, by preventing the growth of their herds. This competition operates through density dependent factors affecting livestock productivity and vulnerability to climate shocks. This competition effect is all the more important since small herders could grow their herd and escape poverty if they were alone in the system. This result shows that density dependent factors could significantly impact herder performances and suggests that forage resource allocation is a driver as powerful as climate, even in the local harsh bioclimatic configuration of the Mongolian Gobi.

Adjuvant chemotherapy in pT1ab node-negative triple-negative breast carcinomas: Results of a national multi-institutional retrospective study.

BACKGROUND: Triple-negative breast cancers (TNBCs) are considered as associated with poor outcome, but prognosis of subcentimetric, node-negative disease remains controversial and evidence that adjuvant chemotherapy (CT) is effective in these small tumours remains limited. PATIENTS AND METHODS: Our objective was to investigate the impact of CT on survival in pT1abN0M0 TNBC. Patients were retrospectively identified from a cohort of 22,475 patients who underwent primary surgery in 15 French centres between 1987 and 2013. As rare pathological types may display very particular prognoses in these tumours, we retained only the invasive ductal carcinomas of no special type according to the last World Health Organisation (WHO) classification which is the most common TNBC histological type. End-points were disease-free survival (DFS) and metastasis-free survival (MFS). A propensity score for receiving CT was estimated using a logistic regression including age, tumour size, Scarff Bloom and Richardson (SBR) grade and lymphovascular invasion. RESULTS: Of a total of 284 patients with pT1abN0M0 ductal TNBC, 144 (51%) received CT and 140 (49%) did not. Patients receiving CT had more adverse prognostic features, such as tumour size, high grade, young age, and lymphovascular invasion. CT was not associated with a significant benefit for DFS (Hazard ratio, HR = 0.77 [0.40-1.46]; p = 0.419, log-rank test) or MFS (HR = 1.00 [0.46-2.19]; p = 0.997), with 5-year DFS and MFS in the group with CT versus without of 90% [81-94%] versus 84% [74-90%], and 90% [81-95%] versus 90% [83%-95%], respectively. Results were consistent in all supportive analyses including multivariate Cox model and the use of the propensity score for adjustment and as a matching factor for case-control analyses. CONCLUSIONS: This study did not identify a significant DFS or MFS advantage for CT in subcentimetric, node-negative ductal TNBC. Although current consensus guidelines recommend consideration of CT in all TNBC larger than 5 mm, clinicians should carefully discuss benefit/risk ratio with patients, given the unproven benefits.

Highly favorable outcome in BRCA-mutated metastatic breast cancer patients receiving high-dose chemotherapy and autologous hematopoietic stem cell transplantation.

Breast cancer carrying BRCA mutation may be highly sensitive to DNA-damaging agents. We hypothesized a better outcome for BRCA-mutated (BRCA(mut)) metastatic breast cancer (MBC) patients receiving high-dose chemotherapy and autologous hematopoietic stem cell transplantation (HDC AHSCT) versus unaffected BRCA (BRCA wild type; (BRCA(wt))) or patients without documented BRCA mutation (BRCA untested (BRCA(ut))). All female patients treated for MBC with AHSCT at Institut Paoli-Calmettes between 2003 and 2012 were included. BRCA(mut) and BRCA(wt) patients were identified from our institutional genetic database. Overall survival (OS) was the primary end point. A total of 235 patients were included. In all, 15 patients were BRCA(mut), 62 BRCA(wt) and 149 BRCA(ut). In multivariate analyses, the BRCA(mut) status was an independent prognostic factor for OS (hazard ratio (HR): 3.08, 95% confidence interval (CI): 1.10-8.64, P=0.0326) and PFS (HR: 2.52, 95% CI :1.29-4.91, P=0.0069). In this large series of MBC receiving HDC AHSCT, we report a highly favorable survival outcome in the subset of patients with documented germline BRCA mutations.

Trade-offs between pasture production and farmland bird conservation: exploration of options using a dynamic farm model.

In European grassland landscapes, grazing and mowing play a key role for the maintenance of high-quality habitats that host important bird populations. As grasslands are also key resources for cattle feeding, there is a need to develop management strategies that achieve the double objective of production and biodiversity conservation. The objective of this study was to use a modelling approach to generate recognisable patterns of bird dynamics in farms composed of different land use proportions, and to compare their production and ecological dimensions. We developed a dynamic model, which linked grassland management to bird population dynamics at the field and farm levels. The model was parameterised for two types of suckling farms corresponding to contrasting levels of grassland intensification and for two bird species of high conservation value. A viability algorithm was used to define and assess viable management strategies for production and ecological performance so as to draw the shape of the relationship between both types of performances for the two types of farms. Our results indicated that, at the farm level, there was a farming system effect with a negative and non-linear relationship linking performance. Improving bird population maintenance was less costly in extensive farms compared with intensive farms. At the field level, the model predicted the timing and intensity of land use, maximising either production or ecological performance. The results suggested that multi-objective grassland management would benefit from public policies that consider levels of organisation higher than the field level, such as the farm or the landscape.

Dose-related effect of moxisylyte on maximal urethral closing pressure in patients with spinal cord injuries.

The effects of single intravenous doses of 0.25, 0.50, and 0.75 mg/kg moxisylyte on maximum urethral closure pressure were evaluated in a placebo-controlled double-blind experiment in 20 patients with spinal cord injuries. Pharmacodynamic testing was performed until 30 minutes, and blood pressure was assessed until 60 minutes. Our findings showed a dose-dependent decrease in maximum urethral closure pressure. At each individual time point, the three doses differed significantly from placebo. Ten minutes after dose administration the maximum effect (48% decrease) was obtained with 0.75 mg/kg. A significant difference in favor of the highest dose was shown from 15 to 20 minutes after administration. According to these findings and because 0.75 mg/kg was as well tolerated as the two other doses, such a drop in pressure indicates that the alpha-blocking agent moxisylyte may be an effective means of decreasing urethral resistance, with obvious implications for the management of urinary obstruction.

Comparison of direct coronary stenting with and without balloon predilatation in patients with stable angina pectoris. BET (Benefit Evaluation of Direct Coronary Stenting) Study Group.

The purpose of this study was to compare the effects of stent placement with and without balloon predilatation on duration of the procedure, reduction of procedure-related costs, and clinical outcomes. Although preliminary trials of direct coronary stenting have demonstrated promising results, the lack of randomized studies with long-term follow-up has limited the critical evaluation of the role of direct stenting in the treatment of obstructive coronary artery disease. Between January and September 1999, 338 patients were randomly assigned to either direct stent implantation (DS+; 173 patients) or standard stent implantation with balloon predilatation (DS-; 165 patients). Baseline clinical and angiographic characteristics were similar in the 2 groups. Procedural success was achieved in 98.3% of patients assigned to DS+ and 97.5% of patients assigned to DS- (p = NS), with a crossover rate of 13.9%. Compared with DS-, DS+ conferred a dramatic reduction in procedure-related cost ($956.4 +/- $352.2 vs $1,164.6 +/- $383.9, p <0.0001) and duration of the procedure (424.2 +/- 412.1 vs 634.5 +/- 390.1 seconds, p < 0.0001). At 6-month follow-up, the incidence of major adverse cardiac events including death, angina pectoris, myocardial infarction, congestive heart failure, repeat angioplasty, or coronary artery bypass graft surgery was 5.3% in DS+ and 11.4% in DS- (p = NS). Multivariate analysis demonstrated that major adverse cardiac events rates were related to stent length of 10 mm (relative risk [RR] 3.25, 95% confidence intervals [CI] 1.36 to 7.78; p = 0.008), stent diameter of 3 mm (RR 2.69, 95% CI 1.03 to 7.06; p = 0.043), and complex lesion type C (RR 2.83, 95% CI 1.02 to 7.85; p = 0.045). Thus, in selected patients, this prospective randomized study shows the feasibility of DS+ with reduction in procedural cost and length, and without an increase in in-hospital clinical events and major adverse cardiac events at 6-month follow-up.

Tau and apo E in CSF: potential aid for discriminating Alzheimer's disease from other dementias.

To evaluate the usefulness of tau proteins as biological markers in the diagnosis of dementia of the Alzheimer type (DAT), we analyzed the concentration of tau proteins in 253 cerebrospinal fluid (CSF) samples from patients with or without neurological disorders. Our study showed a significant increase of the mean CSF tau concentration in DAT patients compared with that from non-DAT patients. Interestingly, a significative decrease of CSF tau in patients with frontotemporal dementia was found. We also observed a positive correlation between the CSF-tau concentration and the number of apoepsilon4 alleles. The CSF apolipoprotein E concentration was evaluated and revealed no variation between the groups, although we observed a significant correlation between CSF tau and apolipoprotein E in DAT patients.

Transaxillary latissimus dorsi flap reconstruction in head and neck cancer. Limitations and refinements in 56 cases.

The transaxillary latissimus dorsi musculocutaneous flap is suitable whenever a large volume of tissue is required for head and neck reconstruction. Fifty-six transaxillary latissimus dorsi musculocutaneous flap reconstructions were performed in 55 patients. There were two cases of complete flap necrosis and eight cases of partial flap necrosis. The latissimus dorsi vascular pedicle is separate from the irradiated field. The pedicled latissimus dorsi flap provides coverage of the orbitocranium, including the supraorbital region and central portion of the upper face. In the event that the pedicled latissimus dorsi flap does not reach far enough cephalad, the nutrient vessels may be separated from the axillary artery and anastomosed to vessels in the neck. Combined defects of the esophagus, mandibulofacial region, and neck may be reconstructed with a single large latissimus dorsi flap. Hairless skin particularly suitable for oral cavity reconstruction is usually available. Aesthetic and functional deficits are minimal after latissimus dorsi reconstruction. Disadvantages of this technique include repositioning of the patient, increased blood loss, and longer operating time. Permanent brachial plexus injury may occur. The latissimus dorsi musculocutaneous flap should not be used when defects can be reconstructed by simpler methods.

Quantitative thin-layer and high-performance liquid chromatographic determination of lorapride in biological fluids and a pharmacokinetic study in humans.

Lorapride has been determined in plasma, red blood cells, and urine by HPLC. The detection was performed at a short wavelength (226 nm), resulting in a detection limit of 10 ng/mL (amount injected was 3.5 ng). Reproducibility of analytical and chromatographic methods through statistical coefficients of variation was 4%. By TLC, only levels in urine were determined. Urine samples were spotted directly on the plate; lorapride was determined after spraying the plate with the Bratton-Marshall reagent, and measurements were carried out in the simultaneous reflectance and transmittance mode (540 nm). The detection limit was 10 ng spotted. Lorapride amounts in urine determined by the two methods were compared by statistical analysis. Examples of kinetics after intravenous and oral administration (100 mg) in humans are given.

In vitro detection of indirect-acting genotoxins in the comet assay using Hep G2 cells.

The induction of DNA damage by four known promutagens (cyclophosphamide (CP), benzo(a)pyrene (BP), dimethylbenz(a)anthracene and 2-acetylaminofluorene (2AAF) was investigated on Hep G2 using the alkaline single cell electroporesis (SCGE) test, most often referred as the "comet assay". After a 3-day incubation, lysed cells embedded in agarose were electrophoresed under alkaline conditions, dyed with a SYBRgold fluorogen and analysed by the Komet software. Among the comet parameters provided by the image analysis program, statistical analysis did not identify any in particular that could best represent the DNA damages. All promutagens, when compared with the control, caused a statistically significant increase in DNA migration as determined by different parameters such as Olive tail moment, tail extent moment, tail/head or tail length. The data demonstrated the ability and the sensitivity of the comet assay when performed on Hep G2 in the detection of DNA damage induced by promutagens, and its suitability in mutagenicity testing in in vitro short-term assays.

A method of age estimation using Raman microspectrometry imaging of the human dentin.

The aim of this work is to establish a correlation between ageing and Raman spectra imaging of human teeth. Raman spectrum of an analysed sample is characteristic of its chemical components. By exploring the different dentinal areas on each tooth, we sought to find a correlation between noticeable variability on Raman spectra and the stages of dentinal evolution with advancing age. A study on 30 teeth analysed by Raman microspectrometry was used to select predictors of age, and it allowed us to determine a regression formula, with age as a dependent variable. Our data were computed by means of a statistical method called partial least squares (PLS) regression. This method was specially adapted for this kind of situation, where we have numerous predictors and relatively few observations. The regression formula was performed on a test sample of four more teeth, and we obtained a correct age estimation, with a mean error of more or less than 5 years. The main benefits of this method was a minimal and non-destructive tooth preparation, which led to an efficient age prediction, for any age group.