Entity

Time filter

Source Type

Dartmouth, Lebanon

Bodelon C.,U.S. National Cancer Institute | Pfeiffer R.M.,U.S. National Cancer Institute | Bollati V.,University of Milan | Debbache J.,U.S. National Cancer Institute | And 21 more authors.
PLoS ONE | Year: 2012

The relationship between telomeres, nevi and melanoma is complex. Shorter telomeres have been found to be associated with many cancers and with number of nevi, a known risk factor for melanoma. However, shorter telomeres have also been found to decrease melanoma risk. We performed a systematic analysis of telomere-related genes and tagSNPs within these genes, in relation to the risk of melanoma, dysplastic nevi, and nevus count combining data from four studies conducted in Italy. In addition, we examined whether telomere length measured in peripheral blood leukocytes is related to the risk of melanoma, dysplastic nevi, number of nevi, or telomere-related SNPs. A total of 796 cases and 770 controls were genotyped for 517 SNPs in 39 telomere-related genes genotyped with a custom-made array. Replication of the top SNPs was conducted in two American populations consisting of 488 subjects from 53 melanoma-prone families and 1,086 cases and 1,024 controls from a case-control study. We estimated odds ratios for associations with SNPs and combined SNP P-values to compute gene region-specific, functional group-specific, and overall P-value using an adaptive rank-truncated product algorithm. In the Mediterranean population, we found suggestive evidence that RECQL4, a gene involved in genome stability, RTEL1, a gene regulating telomere elongation, and TERF2, a gene implicated in the protection of telomeres, were associated with melanoma, the presence of dysplastic nevi and number of nevi, respectively. However, these associations were not found in the American samples, suggesting variable melanoma susceptibility for these genes across populations or chance findings in our discovery sample. Larger studies across different populations are necessary to clarify these associations.


Davies J.R.,University of Leeds | Davies J.R.,St Jamess Hospital | Chang Y.-M.,University of Leeds | Bishop D.T.,University of Leeds | And 30 more authors.
Cancer Epidemiology Biomarkers and Prevention | Year: 2015

Background: We report the development of a cutaneous melanoma risk algorithm based upon seven factors; hair color, skin type, family history, freckling, nevus count, number of large nevi, and history of sunburn, intended to form the basis of a selfassessment Web tool for the general public. Methods: Predicted odds of melanoma were estimated by analyzing a pooled dataset from 16 case-control studies using logistic random coefficients models. Risk categories were defined based on the distribution of the predicted odds in the controls from these studies. Imputation was used to estimate missing data in the pooled datasets. The 30th, 60th, and 90th centiles were used to distribute individuals into four risk groups for their age, sex, and geographic location. Crossvalidation was used to test the robustness of the thresholds for each group by leaving out each study one by one. Performance of the model was assessed in an independent UK case-control study dataset. Results: Cross-validation confirmed the robustness of the threshold estimates. Cases and controls were well discriminated in the independent dataset [area under the curve, 0.75; 95% confidence interval (CI), 0.73-0.78]. Twenty-nine percent of cases were in the highest risk group compared with 7% of controls, and 43% of controls were in the lowest risk group compared with 13% of cases. Conclusion: We have identified a composite score representing an estimate of relative risk and successfully validated this score in an independent dataset. Impact: This score may be a useful tool to inform members of the public about their melanoma risk. © 2015 American Association for Cancer Research.


Wisdom J.P.,Riverside Research Institute | Manuel J.I.,Riverside Research Institute | Drake R.E.,Dartmouth University
Psychiatric Services | Year: 2011

Objective: People experiencing a first episode of psychosis frequently have co-occurring substance use disorders, usually involving alcohol and cannabis, which put them at risk for prolonged psychosis, psychotic relapse, and other adverse outcomes. Yet few studies of first-episode psychosis have addressed the course of substance use disorders and the response to specialized substance abuse treatments. Methods: The authors searched MEDLINE, PsycINFO, and other medical databases for English-language articles published between 1990 and 2009. Included studies addressed two research questions. First, do some clients become abstinent after a first episode of psychosis without specialized substance abuse treatments? Second, for clients who continue to use substances after a first episode of psychosis, does the addition of specialized substance abuse treatment enhance outcomes? Results: Nine studies without specialized substance abuse treatment and five with specialized substance abuse treatment assessed the course of substance use (primarily cannabis and alcohol) after a first episode of psychosis. Many clients (approximately half) became abstinent or significantly reduced their alcohol and drug use after a first episode of psychosis. The few available studies of specialized substance abuse treatments did not find better rates of abstinence or reduction. Conclusions: Experience, education, treatment, or other factors led many clients to curtail their substance use disorders after a first episode of psychosis. Specialized interventions for others need to be developed and tested.


Stefancic A.,Columbia University | Tsemberis S.,Columbia University | Messeri P.,Columbia University | Drake R.,Dartmouth University | Goering P.,University of Toronto
American Journal of Psychiatric Rehabilitation | Year: 2013

Pathways Housing First (PHF) is an innovative, evidence-based model of providing permanent housing and services to adults with severe mental illness. This approach has been widely and rapidly disseminated across the U.S. and internationally, but sometimes with considerable variability from the original PHF model. This study developed and validated a PHF fidelity scale. The PHF model's guiding principles and prospective ingredients were identified through reviews of PHF literature and relevant fidelity scales, interviews with PHF administrators, and a survey administered to HF providers. An expert panel developed the items into a fidelity scale, which was field-tested as part of two large-scale research initiatives in California and Canada. General guiding principles for PHF included (a) eliminating barriers to housing access and retention, (b) fostering a sense of home, (c) facilitating community integration and minimizing stigma, (d) utilizing a harm-reduction approach, and (e) adhering to consumer choice and providing individualized consumer-driven services that promote recovery. The provider survey demonstrated that 32 key ingredients, derived from these principles, had good face and content validity. An expert panel refined the wording of these ingredients, added new items when there was consensus, and developed operational criteria to measure them. The resulting 38-item fidelity scale generally had good internal consistency; it captured variability in program implementation; it demonstrated discriminant validity; and it was useful in guiding program implementation and technical assistance. In conjunction with other program materials, the fidelity scale can be used as a guide for program development and technical assistance and as a research tool. Examining how these key ingredients relate to the model's success will contribute to a broader understanding of how to end homelessness and facilitate recovery. © 2013 Taylor and Francis Group, LLC.


News Article | April 9, 2016
Site: motherboard.vice.com

Love it or hate it, there’s no question that street art has become a firmly entrenched aspect of urban cultures around the world. Styles range from hastily scrawled obscenities and tags to stencils and wildstyle, but as any veteran street artist is wont to tell you, the larger the piece, the more technical expertise is required. The reasons that requisite skill scales up with the size of a street mural are manifold: some are intensely practical (larger pieces are harder to hide from the law) while others are simply a matter of artistic vision (proportion, color and other aspects of painting become more difficult when you can only look at small parts of the piece at a time). Yet thanks to the work of a team of researchers from Dartmouth University, massive photorealistic spray paint murals can now be done by anyone outfitted with their new high-tech, motion sensing spray paint can. "Typically, computationally-assisted painting methods are restricted to the computer," said Wojciech Jarosz, an assistant professor of computer science at Dartmouth. "In this research, we show that by combining computer graphics and computer vision techniques, we can bring such assistance technology to the physical world even for this very traditional painting medium, creating a somewhat unconventional form of digital fabrication.” As the team details in a study published this week inComputers & Graphics, their spray paint can allows a painter to reproduce a photo as a spray mural with staggering accuracy—with little to no skill required on the part of the painter. To begin, the researchers selected a photo they wanted writ large on a canvas or wall and uploaded it to a computer. Next, they took a normal spray paint can and outfitted its nozzle with a QR-cube to track the can’s motion and an actuation device which controls the amount of paint released from the can. Using two webcams to track the can’s motion relative to the wall, an algorithm designed by the researchers ‘told’ the can how much paint to release and as the painter waved the can around in front of the canvas. Although computer-aided painting dates back to Desmond Paul Henry’s Drawing Machine in 1962, prior to the Dartmouth team’s invention, none of the research in this field has allowed non-artists to reproduce images at this scale. Moreover, the researchers hope that as their design becomes more sophisticated, it can be used to recreate images on more complicated, curved surfaces. Paramount to the researchers, however, was maintaining the integrity of the art form despite relinquishing much of the artistic control to a computer algorithm. Counter-clockwise: Input image, computer simulated painting, actual painting done by the smart spray can”; Image: Wojciech Jarosz “Our assistive approach is like a modern take on 'paint by numbers' for spray painting,” said Jarosz. “Most importantly, we wanted to maintain the aesthetic aspects of physical spray painting and the tactile experience of holding and waving a physical spray can while enabling unskilled users to create a physical piece of art."

Discover hidden collaborations