359 research outputs found
Background risk of breast cancer and the association between physical activity and mammographic density
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Flight of the dragonflies and damselflies
This work is a synthesis of our current understanding of the mechanics, aerodynamics and visually mediated control of dragonfly and damselfly flight, with the addition of new experimental and computational data in several key areas. These are: the diversity of dragonfly wing morphologies, the aerodynamics of gliding flight, force generation in flapping flight, aerodynamic efficiency, comparative flight performance and pursuit strategies during predatory and territorial flights. New data are set in context by brief reviews covering anatomy at several scales, insect aerodynamics, neuromechanics and behaviour. We achieve a new perspective by means of a diverse range of techniques, including laser-line mapping of wing topographies, computational fluid dynamics simulations of finely detailed wing geometries, quantitative imaging using particle image velocimetry of on-wing and wake flow patterns, classical aerodynamic theory, photography in the field, infrared motion capture and multi-camera optical tracking of free flight trajectories in laboratory environments. Our comprehensive approach enables a novel synthesis of datasets and subfields that integrates many aspects of flight from the neurobiology of the compound eye, through the aeromechanical interface with the surrounding fluid, to flight performance under cruising and higher-energy behavioural modes
Influence of resource availability on the foraging strategies of the triangle butterflyfish chaetodon triangulum in the Maldives.
Obligate coral feeders such as many members of the Chaetodontidae family (also known as butterflyfish) often show strong preferences for particular coral species. This is thought to have evolved through natural selection as an energy-maximising strategy. Although some species remain as highly specialised feeders throughout their lifetime, many corallivores show a degree of dietary versatility when food abundance is limited; a strategy described by the optimal foraging theory. This study aimed to examine if, within-reef differences in the feeding regime and territory size of the Triangle Butterflyfish Chaetodon triangulum occurred, as a function of resource availability. Results showed that the dietary specialisation of C. triangulum was significant in both areas of low and high coral cover (χL22 = 2.52 x 102, P<0.001 and χL22 = 3.78 x 102, P<0.001 respectively). Resource selection functions (RSFs), calculated for the two main sites of contrasting coral assemblage, showed that in the resource-rich environments, only two Genera (Acropora and Pocillopora) were preferentially selected for, with the majority of other corals being actively ‘avoided’. Conversely, in territories of lower coral coverage, C. triangulum was being less selective in its prey choice and consuming corals in a more even distribution with respect to their availability. Interestingly, coral cover appeared to show no significant effect on feeding rate, however it was a primary determinant of territory size. The findings of the study agree with the predictions of the optimal foraging theory, in that where food supply is scarce, dietary specialisation is minimised and territory size increased. This results in maximising energy intake. This study represents the first scientific evidence that C. triangulum is an obligate corallivore and, as with many other butterflyfish, is therefore dependent on healthy scleractinian corals for survival.N
Novel Associations between Common Breast Cancer Susceptibility Variants and Risk-Predicting Mammographic Density Measures.
Mammographic density measures adjusted for age and body mass index (BMI) are heritable predictors of breast cancer risk, but few mammographic density-associated genetic variants have been identified. Using data for 10,727 women from two international consortia, we estimated associations between 77 common breast cancer susceptibility variants and absolute dense area, percent dense area and absolute nondense area adjusted for study, age, and BMI using mixed linear modeling. We found strong support for established associations between rs10995190 (in the region of ZNF365), rs2046210 (ESR1), and rs3817198 (LSP1) and adjusted absolute and percent dense areas (all P < 10(-5)). Of 41 recently discovered breast cancer susceptibility variants, associations were found between rs1432679 (EBF1), rs17817449 (MIR1972-2: FTO), rs12710696 (2p24.1), and rs3757318 (ESR1) and adjusted absolute and percent dense areas, respectively. There were associations between rs6001930 (MKL1) and both adjusted absolute dense and nondense areas, and between rs17356907 (NTN4) and adjusted absolute nondense area. Trends in all but two associations were consistent with those for breast cancer risk. Results suggested that 18% of breast cancer susceptibility variants were associated with at least one mammographic density measure. Genetic variants at multiple loci were associated with both breast cancer risk and the mammographic density measures. Further understanding of the underlying mechanisms at these loci could help identify etiologic pathways implicated in how mammographic density predicts breast cancer risk.ABCFS: The Australian Breast Cancer Family Registry (ABCFR; 1992-1995) was supported by
the Australian NHMRC, the New South Wales Cancer Council, and the Victorian Health
Promotion Foundation (Australia), and by grant UM1CA164920 from the USA National
Cancer Institute. The Genetic Epidemiology Laboratory at the University of Melbourne has
also received generous support from Mr B. Hovey and Dr and Mrs R.W. Brown to whom we
are most grateful. The content of this manuscript does not necessarily reflect the views or
policies of the National Cancer Institute or any of the collaborating centers in the Breast
Breast Cancer Susceptibility Variants and Mammographic Density
5
Cancer Family Registry (BCFR), nor does mention of trade names, commercial products, or
organizations imply endorsement by the USA Government or the BCFR.
BBCC: This study was funded in part by the ELAN-Program of the University Hospital
Erlangen; Katharina Heusinger was funded by the ELAN program of the University Hospital
Erlangen. BBCC was supported in part by the ELAN program of the Medical Faculty,
University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nuremberg.
EPIC-Norfolk: This study was funded by research programme grant funding from Cancer
Research UK and the Medical Research Council with additional support from the Stroke
Association, British Heart Foundation, Department of Health, Research into Ageing and
Academy of Medical Sciences.
MCBCS: This study was supported by Public Health Service Grants P50 CA 116201, R01 CA
128931, R01 CA 128931-S01, R01 CA 122340, CCSG P30 CA15083, from the National Cancer
Institute, National Institutes of Health, and Department of Health and Human Services.
MCCS: Melissa C. Southey is a National Health and Medical Research Council Senior
Research Fellow and a Victorian Breast Cancer Research Consortium Group Leader. The
study was supported by the Cancer Council of Victoria and by the Victorian Breast Cancer
Research Consortium.
MEC: National Cancer Institute: R37CA054281, R01CA063464, R01CA085265, R25CA090956,
R01CA132839.
MMHS: This work was supported by grants from the National Cancer Institute, National
Institutes of Health, and Department of Health and Human Services. (R01 CA128931, R01 CA
128931-S01, R01 CA97396, P50 CA116201, and Cancer Center Support Grant P30 CA15083).
Breast Cancer Susceptibility Variants and Mammographic Density
6
NBCS: This study has been supported with grants from Norwegian Research Council
(#183621/S10 and #175240/S10), The Norwegian Cancer Society (PK80108002,
PK60287003), and The Radium Hospital Foundation as well as S-02036 from South Eastern
Norway Regional Health Authority.
NHS: This study was supported by Public Health Service Grants CA131332, CA087969,
CA089393, CA049449, CA98233, CA128931, CA 116201, CA 122340 from the National
Cancer Institute, National Institutes of Health, Department of Health and Human Services.
OOA study was supported by CA122822 and X01 HG005954 from the NIH; Breast Cancer
Research Fund; Elizabeth C. Crosby Research Award, Gladys E. Davis Endowed Fund, and the
Office of the Vice President for Research at the University of Michigan. Genotyping services
for the OOA study were provided by the Center for Inherited Disease Research (CIDR), which
is fully funded through a federal contract from the National Institutes of Health to The Johns
Hopkins University, contract number HHSN268200782096.
OFBCR: This work was supported by grant UM1 CA164920 from the USA National Cancer
Institute. The content of this manuscript does not necessarily reflect the views or policies of
the National Cancer Institute or any of the collaborating centers in the Breast Cancer Family
Registry (BCFR), nor does mention of trade names, commercial products, or organizations
imply endorsement by the USA Government or the BCFR.
SASBAC: The SASBAC study was supported by Märit and Hans Rausing’s Initiative against
Breast Cancer, National Institutes of Health, Susan Komen Foundation and Agency for
Science, Technology and Research of Singapore (A*STAR).
Breast Cancer Susceptibility Variants and Mammographic Density
7
SIBS: SIBS was supported by program grant C1287/A10118 and project grants from Cancer
Research UK (grant numbers C1287/8459).
COGS grant: Collaborative Oncological Gene-environment Study (COGS) that enabled the
genotyping for this study. Funding for the BCAC component is provided by grants from the
EU FP7 programme (COGS) and from Cancer Research UK. Funding for the iCOGS
infrastructure came from: the European Community's Seventh Framework Programme
under grant agreement n° 223175 (HEALTH-F2-2009-223175) (COGS), Cancer Research UK
(C1287/A10118, C1287/A 10710, C12292/A11174, C1281/A12014, C5047/A8384,
C5047/A15007, C5047/A10692), the National Institutes of Health (CA128978) and Post-
Cancer GWAS initiative (1U19 CA148537, 1U19 CA148065 and 1U19 CA148112 - the GAMEON
initiative), the Department of Defence (W81XWH-10-1-0341), the Canadian Institutes of
Health Research (CIHR) for the CIHR Team in Familial Risks of Breast Cancer, Komen
Foundation for the Cure, the Breast Cancer Research Foundation, and the Ovarian Cancer
Research Fund.This is the author accepted manuscript. The final version is available via American Association for Cancer Research at http://cancerres.aacrjournals.org/content/early/2015/04/10/0008-5472.CAN-14-2012.abstract
A low-carbohydrate diet may prevent end-stage renal failure in type 2 diabetes. A case report
An obese patient with type 2 diabetes whose diet was changed from the recommended high-carbohydrate, low-fat type to a low-carbohydrate diet showed a significant reduction in bodyweight, improved glycemic control and a reversal of a six year long decline of renal function. The reversal of the renal function was likely caused by both improved glycemic control and elimination of the patient's obesity. Insulin treatment in type 2 diabetes patients usually leads to weight increase which may cause further injury to the kidney. Although other unknown metabolic mechanisms cannot be excluded, it is likely that the obesity caused by the combination of high-carbohydrate diet and insulin in this case contributed to the patient's deteriorating kidney function. In such patients, where control of bodyweight and hyperglycemia is vital, a trial with a low-carbohydrate diet may be appropriate to avoid the risk of adding obesity-associated renal failure to already failing kidneys
The association of tidal EFL with exercise performance, exacerbations, and death in COPD
Background: Tidal expiratory flow limitation (EFLT) is frequently found in patients with COPD and can be detected by forced oscillations when within-breath reactance of a single-breath is â\u89¥0.28 kPa·s·L-1. The present study explored the association of within-breath reactance measured over multiple breaths and EFLT with 6-minute walk distance (6MWD), exacerbations, and mortality. Methods: In 425 patients, spirometry and forced oscillation technique measurements were obtained on eight occasions over 3 years. 6MWD was assessed at baseline and at the 3-year visit. Respiratory symptoms, exacerbations, and hospitalizations were recorded. A total of 5-year mortality statistics were retrieved retrospectively. We grouped patients according to the mean within-breath reactance (Î\u94(Formula Presented.)), measured over several breaths at baseline, calculated as mean inspiratory-mean expiratory reactance over the sampling period. In addition to the established threshold of EFLT, an upper limit of normal (ULN) was defined using the 97.5th percentile of Î\u94(Formula Presented.) of the healthy controls in the study; 6MWDs were compared according to Î\u94(Formula Presented.), as normal, â\u89¥ ULN < EFLT, or â\u89¥ EFLT. Annual exacerbation rates were analyzed using a negative binomial model in the three groups, supplemented by time to first exacerbation analysis, and dichotomizing patients at the ULN. Results: In patients with COPD and baseline Î\u94(Formula Presented.) below the ULN (0.09 kPa·s·L-1), 6MWD was stable. 6MWD declined significantly in patients with Î\u94(Formula Presented.) â\u89¥ ULN. Worse lung function and more exacerbations were found in patients with COPD with Î\u94(Formula Presented.) â\u89¥ ULN, and patients with Î\u94(Formula Presented.) â\u89¥ ULN had shorter time to first exacerbation and hospitalization. A significantly higher mortality was found in patients with Î\u94(Formula Presented.) â\u89¥ ULN and FEV1.50%. Conclusion: Patients with baseline Î\u94(Formula Presented.) â\u89¥ ULN had a deterioration in exercise performance, more exacerbations, and greater hospitalizations, and, among those with moderate airway obstruction, a higher mortality. Î\u94(Formula Presented.) is a novel independent marker of outcome in COPD
Fine Mapping the Spatial Distribution and Concentration of Unlabeled Drugs within Tissue Micro-Compartments Using Imaging Mass Spectrometry
Readouts that define the physiological distributions of drugs in tissues are an unmet challenge and at best imprecise, but are needed in order to understand both the pharmacokinetic and pharmacodynamic properties associated with efficacy. Here we demonstrate that it is feasible to follow the in vivo transport of unlabeled drugs within specific organ and tissue compartments on a platform that applies MALDI imaging mass spectrometry to tissue sections characterized with high definition histology. We have tracked and quantified the distribution of an inhaled reference compound, tiotropium, within the lungs of dosed rats, using systematic point by point MS and MS/MS sampling at 200 µm intervals. By comparing drug ion distribution patterns in adjacent tissue sections, we observed that within 15 min following exposure, tiotropium parent MS ions (mass-to-charge; m/z 392.1) and fragmented daughter MS/MS ions (m/z 170.1 and 152.1) were dispersed in a concentration gradient (80 fmol-5 pmol) away from the central airways into the lung parenchyma and pleura. These drug levels agreed well with amounts detected in lung compartments by chemical extraction. Moreover, the simultaneous global definition of molecular ion signatures localized within 2-D tissue space provides accurate assignment of ion identities within histological landmarks, providing context to dynamic biological processes occurring at sites of drug presence. Our results highlight an important emerging technology allowing specific high resolution identification of unlabeled drugs at sites of in vivo uptake and retention
Long-term outcome of displaced radial neck fractures in adulthood: 16–21 year follow-up of 5 patients treated with radial head excision
Background There have been no reports on the long-term outcome of radial neck Mason type IIIb fractures in adults
The efficacy of hypotonic and near-isotonic saline for parenteral fluid therapy given at low maintenance rate in preventing significant change in plasma sodium in post-operative pediatric patients: protocol for a prospective randomized non-blinded study
<p>Abstract</p> <p>Background</p> <p>Hyponatremia is the most frequent electrolyte abnormality observed in post-operative pediatric patients receiving intravenous maintenance fluid therapy. If plasma sodium concentration (p-Na<sup>+</sup>) declines to levels below 125 mmol/L in < 48 h, transient or permanent brain damage may occur. There is an intense debate as to whether the administered volume (full rate <it>vs. </it>restricted rate of infusion) and the composition of solutions used for parenteral maintenance fluid therapy (hypotonic <it>vs. </it>isotonic solutions) contribute to the development of hyponatremia. So far, there is no definitive pediatric data to support a particular choice of parenteral fluid for maintenance therapy in post-surgical patients.</p> <p>Methods/Design</p> <p>Our prospective randomized non-blinded study will be conducted in healthy children and adolescents aged 1 to 14 years who have been operated for acute appendicitis. Patients will be randomized either to intravenous hypotonic (0.23% or 0.40% sodium chloride in glucose, respectively) or near-isotonic (0.81% sodium chloride in glucose) solution given at approximately three-fourths of the average maintenance rate. The main outcome of interest from this study is to evaluate 24 h post-operatively whether differences in p-Na<sup>+ </sup>between treatment groups are large enough to be of clinical relevance. In addition, water and electrolyte balance as well as regulatory hormones will be measured.</p> <p>Discussion</p> <p>This study will provide valuable information on the efficacy of hypotonic and near-isotonic fluid therapy in preventing a significant decrease in p-Na<sup>+</sup>. Finally, by means of careful electrolyte and water balance and by measuring regulatory hormones our results will also contribute to a better understanding of the physiopathology of post-operative changes in p-Na<sup>+ </sup>in a population at risk for hyponatremia.</p> <p>Trial registration</p> <p>The protocol for this study is registered with the current controlled trials registry; registry number: <a href="http://www.controlled-trials.com/ISRCTN43896775">ISRCTN43896775</a>.</p
The effect on the small bowel of 5-FU and oxaliplatin in combination with radiation using a microcolony survival assay
<p>Abstract</p> <p>Background</p> <p>In locally advanced rectal cancer, 5-Fluorouracil (5-FU)-based chemoradiation is the standard treatment. The main acute toxicity of this treatment is enteritis. Due to its potential radiosensitizing properties, oxaliplatin has recently been incorporated in many clinical chemoradiation protocols. The aim of this study was to investigate to what extent 5-FU and oxaliplatin influence the radiation (RT) induced small bowel mucosal damage when given in conjunction with single or split dose RT.</p> <p>Methods</p> <p>Immune competent balb-c mice were treated with varying doses of 5-FU, oxaliplatin (given intraperitoneally) and total body RT, alone or in different combinations in a series of experiments. The small bowel damage was studied by a microcolony survival assay. The treatment effect was evaluated using the inverse of the slope (D<sub>0</sub>) of the exponential part of the dose-response curve.</p> <p>Results</p> <p>In two separate experiments the dose-response relations were determined for single doses of RT alone, yielding D<sub>0 </sub>values of 2.79 Gy (95% CI: 2.65 - 2.95) and 2.98 Gy (2.66 - 3.39), for doses in the intervals of 5-17 Gy and 5-10 Gy, respectively. Equitoxic low doses (IC5) of the two drugs in combination with RT caused a decrease in jejunal crypt count with significantly lower D<sub>0</sub>: 2.30 Gy (2.10 - 2.56) for RT+5-FU and 2.27 Gy (2.08 - 2.49) for RT+oxaliplatin. Adding both drugs to RT did not further decrease D<sub>0</sub>: 2.28 Gy (1.97 - 2.71) for RT+5-FU+oxaliplatin. A clearly higher crypt survival was noted for split course radiation (3 × 2.5 Gy) compared to a single fraction of 7.5 Gy. The same difference was seen when 5-FU and/or oxaliplatin were added.</p> <p>Conclusion</p> <p>Combining 5-FU or oxaliplatin with RT lead to an increase in mucosal damage as compared to RT alone in our experimental setting. No additional reduction of jejunal crypt counts was noted when both drugs were combined with single dose RT. The higher crypt survival with split dose radiation indicates a substantial recovery between radiation fractions. This mucosal-sparing effect achieved by fractionation was maintained also when chemotherapy was added.</p
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