369 research outputs found
Hachimoji DNA and RNA: A genetic system with eight building blocks
Reported here are DNA and RNA-like systems built from eight (hachi-) nucleotide letters (-moji) that form four orthogonal pairs. This synthetic genetic biopolymer meets the structural requirements needed to support Darwinism, including a polyelectrolyte backbone, predictable thermodynamic stability, and stereoregular building blocks that fit a Schrödinger aperiodic crystal. Measured thermodynamic parameters predict the stability of hachimoji duplexes, allowing hachimoji DNA to double the information density of natural terran DNA. Three crystal structures show that the synthetic building blocks do not perturb the aperiodic crystal seen in the DNA double helix. Hachimoji DNA was then transcribed to give hachimoji RNA in the form of a functioning fluorescent hachimoji aptamer. These results expand the scope of molecular structures that might support life, including life throughout the cosmos
Gemcitabine, cisplatin and methylprednisolone for the treatment of patients with peripheral T-cell lymphoma: the Royal Marsden Hospital experience
Metabolic biomarkers assessed with PET/CT predict sex-specific longitudinal outcomes in patients with diffuse large B-cell lymphoma
In many cancers, including lymphoma, males have higher incidence and mortality than females. Emerging evidence demonstrates that one mechanism underlying this phenomenon is sex differences in metabolism, both with respect to tumor nutrient consumption and systemic alterations in metabolism, i.e., obesity. We wanted to determine if visceral fat and tumor glucose uptake with fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) could predict sex-dependent outcomes in patients with diffuse large B-cell lymphoma (DLBCL). We conducted a retrospective analysis of 160 patients (84 males; 76 females) with DLBCL who had imaging at initial staging and after completion of therapy. CT-based relative visceral fat area (rVFA), PET-based SUVmax normalized to lean body mass (SULmax), and end-of-treatment FDG-PET 5PS score were calculated. Increased rVFA at initial staging was an independent predictor of poor OS only in females. At the end of therapy, increase in visceral fat was a significant predictor of poor survival only in females. Combining the change in rVFA and 5PS scores identified a subgroup of females with visceral fat gain and high 5PS with exceptionally poor outcomes. These data suggest that visceral fat and tumor FDG uptake can predict outcomes in DLBCL patients in a sex-specific fashion
The effects of postmenopausal hormone therapy on social activity, partner relationship, and sexual life – experience from the EPHT trial
<p>Abstract</p> <p>Background</p> <p>With the exception of sexual functioning and weight, social and behavioural effects of postmenopausal hormone therapy (HT) have not been reported from trials. This paper reports such results from the EPHT-trial in Estonia.</p> <p>Methods</p> <p>A randomized trial, with a blind and non-blind sub-trial in Estonia. From 1999–2001, 1778 women were recruited. The mean follow-up was 3.6 years. Women's experiences were asked in the first and final study year by mailed questionnaires (74 and 81% response rates). Comparisons of the groups were made by cross-tabulation and logistic regression, adjusting for age.</p> <p>Results</p> <p>There were no differences between the HT and non-HT groups in regard to being employed, the extent of social involvement or marital status or opinions on aging. There was no difference in the frequency of free-time exercise, or overweight. Some of the indicators suggested less sexual inactivity, but the differences were small.</p> <p>Conclusion</p> <p>In a trial setting, postmenopausal hormone therapy did not influence work or social involvement or health behaviour.</p> <p>Trial registration</p> <p>ISRCTN35338757</p
Thermodynamic contributions of single internal rA·dA, rC·dC, rG·dG and rU·dT mismatches in RNA/DNA duplexes
The thermodynamic contributions of rA·dA, rC·dC, rG·dG and rU·dT single internal mismatches were measured for 54 RNA/DNA duplexes in a 1 M NaCl buffer using UV absorbance thermal denaturation. Thermodynamic parameters were obtained by fitting absorbance versus temperature profiles using the curve-fitting program Meltwin. The weighted average thermodynamic data were fit using singular value decomposition to determine the eight non-unique nearest-neighbor parameters for each internal mismatch. The new parameters predict the ΔG°37, ΔH° and melting temperature (Tm) of duplexes containing these single mismatches within an average of 0.33 kcal/mol, 4.5 kcal/mol and 1.4°C, respectively. The general trend in decreasing stability for the single internal mismatches is rG·dG > rU·dT > rA·dA > rC·dC. The stability trend for the base pairs 5′ of the single internal mismatch is rG·dC > rC·dG > rA·dT > rU·dA. The stability trend for the base pairs 3′ of the single internal mismatch is rC·dG > rG·dC >> rA·dT > rU·dA. These nearest-neighbor values are now a part of a complete set of single internal mismatch thermodynamic parameters for RNA/DNA duplexes that are incorporated into the nucleic acid assay development software programs Visual oligonucleotide modeling platform (OMP) and ThermoBLAST
Digital approaches to music-making for people with dementia in response to the COVID-19 pandemic: current practice and recommendations
Before COVID-19, dementia singing groups and choirs flourished, providing activity, cognitive stimulation, and social support for thousands of people with dementia in the UK. Interactive music provides one of the most effective psychosocial interventions for people with dementia; it can allay agitation and promote wellbeing. Since COVID-19 has halted the delivery of in-person musical activities, it is important for the welfare of people with dementia and their carers to investigate what alternatives to live music making exist, how these alternatives are delivered and how their accessibility can be expanded. This community case study examines recent practice in online music-making in response to COVID-19 restrictions for people with dementia and their supporters, focusing on a UK context. It documents current opportunities for digital music making, and assesses the barriers and facilitators to their delivery and accessibility. Online searches of video streaming sites and social media documented what music activities were available. Expert practitioners and providers collaborated on this study and supplied input about the sessions they had been delivering, the technological challenges and solutions they had found, and the responses of the participants. Recommendations for best practice were developed and refined in consultation with these collaborators. Over 50 examples of online music activities were identified. In addition to the challenges of digital inclusion and accessibility for some older people, delivering live music online has unique challenges due to audio latency and sound quality. It is necessary to adapt the session to the technology's limitations rather than expect to overcome these challenges. The recommendations highlight the importance of accessibility, digital safety and wellbeing of participants. They also suggest ways to optimize the quality of their musical experience. The pandemic has prompted innovative approaches to deliver activities and interventions in a digital format, Dowson et al. Dementia, COVID-19 and Online Music and people with dementia and their carers have adapted rapidly. While online music is meeting a clear current need for social connection and cognitive stimulation, it also offers some advantages which remain relevant after COVID-19 restrictions are relaxed. The recommendations of this study are intended to be useful to musicians, dementia care practitioners, and researchers during the pandemic and beyond
Performance of the CMS Cathode Strip Chambers with Cosmic Rays
The Cathode Strip Chambers (CSCs) constitute the primary muon tracking device
in the CMS endcaps. Their performance has been evaluated using data taken
during a cosmic ray run in fall 2008. Measured noise levels are low, with the
number of noisy channels well below 1%. Coordinate resolution was measured for
all types of chambers, and fall in the range 47 microns to 243 microns. The
efficiencies for local charged track triggers, for hit and for segments
reconstruction were measured, and are above 99%. The timing resolution per
layer is approximately 5 ns
Defining patient outcomes in stage IV colorectal cancer: a prospective study with baseline stratification according to disease resectability status
BACKGROUND: Stage IV colorectal cancer encompasses a broad patient population in which both curative and palliative management strategies may be used. In a phase II study primarily designed to assess the efficacy of capecitabine and oxaliplatin, we were able to prospectively examine the outcomes of patients with stage IV colorectal cancer according to the baseline resectability status. METHODS: At enrolment, patients were stratified into three subgroups according to the resectability of liver disease and treatment intent: palliative chemotherapy (subgroup A), conversion therapy (subgroup B) or neoadjuvant therapy (subgroup C). All patients received chemotherapy with capecitabine 2000 mg m(-2) on days 1-14 and oxaliplatin 130 mg m(-2) on day 1 repeated every 3 weeks. Imaging was repeated every four cycles where feasible liver resection was undertaken after four or eight cycles of chemotherapy. RESULTS: Of 128 enrolled patients, 74, 22 and 32 were stratified into subgroups A, B and C, respectively. Attempt at curative liver resection was undertaken in 10 (45%) patients in subgroup B and 19 (59%) in subgroup C. The median overall survival was 14.6, 24.5 and 52.9 months in subgroups A, B and C, respectively. For patients in subgroups B and C who underwent an attempt at curative resection, 3-year progression-free survival was 10% in subgroup B and 37% for subgroup C. CONCLUSIONS: This prospective study shows the wide variation in outcome according to baseline resectability status and highlights the potential clinical value of a modified staging system to distinguish between these patient subgroups. British Journal of Cancer (2010) 102, 255-261. doi:10.1038/sj.bjc.6605508 www.bjcancer.com (C) 2010 Cancer Research U
Classification of Types of Stuttering Symptoms Based on Brain Activity
Among the non-fluencies seen in speech, some are more typical (MT) of stuttering speakers, whereas others are less typical (LT) and are common to both stuttering and fluent speakers. No neuroimaging work has evaluated the neural basis for grouping these symptom types. Another long-debated issue is which type (LT, MT) whole-word repetitions (WWR) should be placed in. In this study, a sentence completion task was performed by twenty stuttering patients who were scanned using an event-related design. This task elicited stuttering in these patients. Each stuttered trial from each patient was sorted into the MT or LT types with WWR put aside. Pattern classification was employed to train a patient-specific single trial model to automatically classify each trial as MT or LT using the corresponding fMRI data. This model was then validated by using test data that were independent of the training data. In a subsequent analysis, the classification model, just established, was used to determine which type the WWR should be placed in. The results showed that the LT and the MT could be separated with high accuracy based on their brain activity. The brain regions that made most contribution to the separation of the types were: the left inferior frontal cortex and bilateral precuneus, both of which showed higher activity in the MT than in the LT; and the left putamen and right cerebellum which showed the opposite activity pattern. The results also showed that the brain activity for WWR was more similar to that of the LT and fluent speech than to that of the MT. These findings provide a neurological basis for separating the MT and the LT types, and support the widely-used MT/LT symptom grouping scheme. In addition, WWR play a similar role as the LT, and thus should be placed in the LT type
Should essays and other “open-ended”-type questions retain a place in written summative assessment in clinical medicine?
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