2,977 research outputs found

    Differences in telomere length between sporadic and familial cutaneous melanoma

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    BACKGROUND: Several pieces of evidence indicate that a complex relationship exists between constitutional telomere length (TL) and the risk of cutaneous melanoma. Although the general perception is that longer telomeres increase melanoma risk, some studies do not support this association. We hypothesise that discordant data are due to the characteristics of the studied populations. OBJECTIVES: To evaluate the association of telomere length with familial and sporadic melanoma. METHODS: TL was measured by multiplex quantitative PCR in leukocytes from 310 melanoma patients according to familial/sporadic and single/multiple cancers and 216 age-matched controls. RESULTS: Patients with sporadic melanoma were found to have shorter telomeres as compared to those with familial melanoma. In addition, shorter telomeres, while tending to reduce the risk of familial melanoma regardless of single or multiple tumors, nearly trebled the risk of single sporadic melanoma. CONCLUSIONS: This is the first time that TL has been correlated to opposite effects on melanoma risk according to the presence or absence of familial predisposition. Individual susceptibility to melanoma should be taken into account when assessing the role of TL as a risk factor. This article is protected by copyright. All rights reserved

    INVESTIGATION ON THE DISCRETIZATION OF THE REALISTIC IRREGULAR WAVE GENERATION REGION THROUGH THE WAVEMIMO METHODOLOGY

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    Aiming to contribute to the research related to the sea wave energy conversion, the present paper approaches an investigation of the discretization used in the region of imposition of the prescribed velocity boundary condition, which is necessary for the WaveMIMO methodology. This methodology is employed for the numeric generation of irregular waves based on realistic sea state data. These data (obtained from TOMAWAC software in the present study) are treated to obtain orbital profiles of wave propagation velocity, which are imposed as boundary conditions on the wave channel. In this study, the realistic data considered refers to a point close to the Molhes da Barra, located on the coast of the municipality of Rio Grande, Rio Grande do Sul, Brazil. The numerical simulations were performed in Fluent, a computational fluid dynamics (CFD) software based on the finite volume method (FVM). The volume of fluid (VOF) multiphase model was used on the treatment of the water-air interface. Free surface elevation data obtained when the region of imposition of the prescribed velocity boundary condition was subdivided into 8, 11 and 14 segments were compared. The results found show that the 14 segments discretization represents more precisely the free surface elevation of irregular waves

    Temporal variation in the microbiome of Acropora coral species does not reflect seasonality

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    The coral microbiome is known to fluctuate in response to environmental variation and has been suggested to vary seasonally. However, most studies to date, particularly studies on bacterial communities, have examined temporal variation over a time frame of less than 1 year, which is insufficient to establish if microbiome variations are indeed seasonal in nature. The present study focused on expanding our understanding of long-term variability in microbial community composition using two common coral species, Acropora hyacinthus, and Acropora spathulata, at two mid-shelf reefs on the Great Barrier Reef. By sampling over a 2-year time period, this study aimed to determine whether temporal variations reflect seasonal cycles. Community composition of both bacteria and Symbiodiniaceae was characterized through 16S rRNA gene and ITS2 rDNA metabarcoding. We observed significant variations in community composition of both bacteria and Symbiodiniaceae among time points for A. hyacinthus and A. spathulata. However, there was no evidence to suggest that temporal variations were cyclical in nature and represented seasonal variation. Clear evidence for differences in the microbial communities found between reefs suggests that reef location and coral species play a larger role than season in driving microbial community composition in corals. In order to identify the basis of temporal patterns in coral microbial community composition, future studies should employ longer time series of sampling at sufficient temporal resolution to identify the environmental correlates of microbiome variation

    Telomerase reverse transcriptase locus polymorphisms and cancer risk: a field synopsis and meta-analysis.

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    BACKGROUND: Several recent studies have provided evidence that polymorphisms in the telomerase reverse transcriptase (TERT) gene sequence are associated with cancer development, but a comprehensive synopsis is not available. We conducted a systematic review and meta-analysis of the available molecular epidemiology data regarding the association between TERT locus polymorphisms and predisposition to cancer. METHODS: A systematic review of the English literature was conducted by searching PubMed, Embase, Cancerlit, Google Scholar, and ISI Web of Knowledge databases for studies on associations between TERT locus polymorphisms and cancer risk. Random-effects meta-analysis was performed to pool per-allele odds ratios for TERT locus polymorphisms and risk of cancer, and between-study heterogeneity and potential bias sources (eg, publication and chasing bias) were assessed. Because the TERT locus includes the cleft lip and palate transmembrane 1-like (CLPTM1L) gene, which is in linkage disequilibrium with TERT, CLPTM1L polymorphisms were also analyzed. Cumulative evidence for polymorphisms with statistically significant associations was graded as "strong," "moderate," and "weak" according to the Venice criteria. The joint population attributable risk was calculated for polymorphisms with strong evidence of association. RESULTS: Eighty-five studies enrolling 490 901 subjects and reporting on 494 allelic contrasts were retrieved. Data were available on 67 TERT locus polymorphisms and 24 tumor types, for a total of 221 unique combinations of polymorphisms and cancer types. Upon meta-analysis, a statistically significant association with the risk of any cancer type was found for 22 polymorphisms. Strong, moderate, and weak cumulative evidence for association with at least one tumor type was demonstrated for 11, 9, and 14 polymorphisms, respectively. For lung cancer, which was the most studied tumor type, the estimated joint population attributable risk for three polymorphisms (TERT rs2736100, intergenic rs4635969, and CLPTM1L rs402710) was 41%. Strong evidence for lack of association was identified for five polymorphisms in three tumor types. CONCLUSIONS: To our knowledge, this is the largest collection of data for associations between TERT locus polymorphisms and cancer risk. Our findings support the hypothesis that genetic variability in this genomic region can modulate cancer susceptibility in humans.This work was in part supported by a grant from the Italian Association for Research on Cancer (AIRC Veneto Regional fund 2008-2011 to SM and DN).This is the author accepted manuscript. The final version is available from Oxford University Press via http://dx.doi.org/10.1093/jnci/djs22

    Experimental study of photoionization of ozone in the 12 to 21 eV region

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    The total and partial ion yield of ozone using time-of-flight is presented. The measurements were done using multicoincidence between a photoelectron and a photoion (PEPICO). Comparison with the photoelectron spectrum and previous measurements using other techniques allowed the assignment of most broad features in the spectra. Kinetic energy released is obtained for O+ and O-2(+) ions. A discussion about the dissociation channels is included. (C) 2001 American Institute of Physics.115115041504

    Treatment efficacy with electrochemotherapy: A multi-institutional prospective observational study on 376 patients with superficial tumors

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    BACKGROUND: Cutaneous metastases represent a therapeutic challenge. An increasing body of experience suggests that electrochemotherapy (ECT) provides effective tumor control, although its evidence basis should be strengthened. METHODS: This prospective, multicenter, observational study enrolled patients with superficial metastases, who underwent ECT at 10 centers between 2008 and 2013. Outcomes included adherence to European Standard Operating Procedures of ECT (ESOPE), tumor response, local progression-free survival (LPFS), toxicity and patient-reported outcomes (PROs, EORTC QLQ-C30 plus an 8-item questionnaire). RESULTS: We enrolled 376 eligible patients. Tumor histotype distribution was as follows: melanoma, 56%; squamous cell carcinoma, 11%; Kaposi sarcoma, 11%; breast carcinoma, 8%; basal cell carcinoma, 6%; soft tissue sarcomas, 3%; others, 5%. We registered 1304 target tumors (median size 1 cm). Treatment adhered to ESOPE in 88% of patients as to the route of drug administration, and in 70% as to electrode application. The procedure was mainly performed under sedation (64.6%) and by using intravenous chemotherapy (93.4%). Tumor response rate at 60 days was 88% (complete, 50%). Small tumor size predicted complete response achievement (OR 2.24, p = 0.003), higher LPFS (HR 0.68, p = 0.004) and improved PROs (Global Health Status, p < 0.001; wound bleeding, p < 0.001; healing, p = 0.002; and aesthetics, p < 0.001). Skin toxicity (grade 653, 7.8%) was lower in patients with tumors <2 cm (p 640.001). One-year LPFS was 73.7% (95%CI 68.4-78.3). CONCLUSIONS: ECT represents a valuable skin-directed therapy across a range of malignancies. The most frequently applied treatment modality is intravenous chemotherapy under sedation. Small tumor size predicts durable tumor control, fewer side-effects and better PROs

    Timing of sentinel node biopsy independently predicts disease-free and overall survival in clinical stage I-II melanoma patients: A multicentre study of the Italian Melanoma Intergroup (IMI)

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    Background: Sentinel lymph node biopsy (SNB) still remains a key procedure to appropriately stage melanoma patients and to select those who are candidate to novel treatments with immunotherapy and targeted therapy in the adjuvant setting. The impact of timing of SNB on disease-free survival (DFS) and overall survival (OS) is still unclear. Material and methods: The study was conducted at 6 Italian Melanoma Intergroup (IMI) centres and included 8953 consecutive clinical stage I-II melanoma patients who were diagnosed, treated, and followed up between November 1997 and March 2018. All patients were prospectively included in dedicated IMI database. Multivariable Cox regression analyses were performed to investigate how baseline characteristics and time interval until SNB are related to DFS and OS. Results: Considering the whole population, at multivariable analysis, after adjusting for age, gender, Breslow thickness, site, ulceration, and the SNB status, a delay in the timing of SNB was associated with a better DFS (adjusted hazard ratio [aHR, delayed versus early SNB] 0.98, 95% confidence interval [CI] 0.97\u20130.99, p < 0.001) and OS (aHR 0.98, 95% CI 0.97\u20130.99, p = 0.001). Specifically, in patients with a negative SNB status, a beneficial impact of delayed SNB (i.e. at least 32 days after primary excision) was confirmed for DFS (aHR 0.70, 95%CI 0.63\u20130.79, p < 0.001) and OS (aHR 0.69, 95%CI 0.61\u20130.78, p < 0.001), whereas in those with a positive SNB status, DFS (aHR 0.96, 95%CI 0.84\u20131.09, p = 0.534) and OS (aHR 0.94 95%CI 0.81\u20131.08, p = 0.374) were not significantly different in patients with early or delayed SNB. Conclusions: Our study does not support a strict time interval for SNB. These results may be useful for national guidelines, for counselling patients and reducing the number of high urgency referrals
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