The number of tumor cells spread to sentinel lymph nodes affects melanoma prognosis

http://feeds.feedburner.com/~r/sciencedaily/top_news/top_health/~4/ty4i32_YhLQ

Cancer cell spread to the sentinel node — the lymph node to which cancer cells are most likely to spread from a primary tumor — is a risk factor for melanoma death. According to a study published in this week’s PLOS Medicine by Anja Ulmer, Christoph Klein and colleagues from the Universities of Tbingen and Regensburg, Germany, the prognosis of a patient largely depends on the number of disseminated cancer cells per million lymphocytes in the sentinel node. Even very low numbers were found to be predictive for reduced survival.The leading cause of death from skin disease is melanoma, which is the most dangerous type of skin cancer. When melanoma metastasizes and spreads to other parts of the body, treatment options become limited and the prognosis is poor. Melanoma staging (and prognosis) is currently focused on the primary tumor itself, with characteristics like tumor thickness, mitotic rate, and ulceration (break in the skin caused by the tumor) indicating the likelihood that the tumor has started to spread. Looking for tumor cells in the sentinel nodes is done for patients who are at increased risk for spread, but standard procedures for how to measure spread to the nodes and how to integrate this information with the tumor histology are needed. Since melanoma is one of the deadliest cancers, better predictors of prognosis for melanoma patients are needed for patient information and to determine treatment options.The researchers prospectively collected a large number of samples for this relatively rare cancer: 1,834 sentinel lymph nodes from 1,027 patients with melanoma who had been followed for 5 years after the samples were taken. They labelled disseminated cancer cells (DCCs) in the lymph nodes through the use of a marker for melanoma cells, counted them, and calculated DCC density. They then asked whether DCC density was related to a patient’s survival. They found that patients with high DCC density in the lymph nodes were more likely to die from melanoma within 5 years. …


Read More: The number of tumor cells spread to sentinel lymph nodes affects melanoma prognosis

#Agriculture, #Alzheimer, #Body, #Christophklein, #Current, #Disease, #Health, #King, #Medicine, #Plos, #Standard, #Tbingen

Discovery may help to explain mystery of "missing" genetic risk, susceptibility to common diseases

http://feeds.feedburner.com/~r/sciencedaily/top_news/top_science/~4/ZOo6MCSeck8

A new study could help to answer an important riddle in our understanding of genetics: why research to look for the genetic causes of common diseases has failed to explain more than a fraction of the heritable risk of developing them.Susceptibility to common diseases is believed to arise through a combination of many common genetic variants that individually slightly increase the risk of disease, plus a smaller number of rare mutations that often carry far greater risk.However, even when their effects are added together, the genetic variants so far linked to common diseases account for only a relatively small proportion of the risk we know is conveyed by genetics through studies of family history.But the major new study, published in the journal PLOS Genetics, shows for the first time in cancer that some common genetic variants could actually be indicators of the presence of much more influential rare mutations that have yet to be found.Scientists at The Institute of Cancer Research, London, led an international consortium made up of more than 25 leading academic institutions on the study, which was funded by the European Union.The research, involving 20,440 men with prostate cancer and 21,469 without the disease, identified a cluster of four common genetic variants on chromosome 17 that appeared to give rise to a small increase in prostate cancer risk, using the standard statistical techniques for this type of study.But the study found an alternative explanation for the risk signal — a small proportion of the men with these common variants were in fact carriers of a rare mutation in the nearby HOXB13 gene, which is known to be linked to prostate cancer. Under this ‘synthetic association’, the number of people carrying a cancer risk variant was much lower than had been assumed, but those people who did inherit a variant had a much higher risk of prostate cancer than had been realised.The discovery shows that the prevailing genetic theory — that common cancers are predominantly caused by the combined action of many common genetic variants, each with only a very small effect — could potentially underestimate the impact of rare, as yet undiscovered mutations.The results are important because they show that there is a need for renewed effort by geneticists to find the causal variants, whether common or rare, behind the many common cancer-associated variants identified in recent years.Identifying any underlying rare mutations with a big effect on disease risk could improve the genetic screening and clinical management of individuals at greater risk of developing cancer, as well as other diseases.Study co-leader Dr Zsofia Kote-Jarai, Senior Staff Scientist at The Institute of Cancer Research (ICR), said: “As far as we are aware, this is the first known example of a ‘synthetic association’ in cancer genetics. It was exciting to find evidence for this theory, which predicts that common genetic variants that appear to increase risk of disease by only a modest amount may indeed sometimes be detected purely due to their correlation with a rarer variant which confers a greater risk.”Our study does not imply how widespread this phenomenon may be, but it holds some important lessons for geneticists in cancer, and other common diseases. It demonstrates the importance of identifying the causal genetic changes behind the many common variants that have already been shown to influence risk of disease.”Our study also demonstrates that standard methods to identify potential causal variants when fine-mapping genetic associations with disease may be inadequate to assess the contribution of rare variants. Large sequencing studies may be necessary to answer these questions unequivocally.”Study co-leader Professor Ros Eeles, Professor of Oncogenetics at The Institute of Cancer Research and Honorary Clinical Consultant at The Royal Marsden NHS Foundation Trust, said: “One important unanswered question in cancer genetics — and in genetics of common disease more generally — is why the genetic mutations we’ve discovered so far each seem to have such a small effect, when studies of families have shown that our genetic make-up has a very large influence on our risk of cancer.”Our study is an important step forward in our understanding of where we might find this ‘missing’ genetic risk in cancer. At least in part, it might lie in rarer mutations which current research tools have struggled to find, because individually each does not affect a large number of people.”


Read More: Discovery may help to explain mystery of "missing" genetic risk, susceptibility to common diseases

#Cancer, #Common, #Count, #Discovery, #Disease, #Genetic, #London, #Major, #People, #Professor, #Research, #Standard

Link between selling, leasing market prices for cars studied

http://feeds.feedburner.com/~r/sciencedaily/living_well/~4/tcKmTZ0kLao

Changes in the selling prices of cars can be used to improve calculations for how much people should be paying to lease a vehicle, according to a new study.Researchers from Norwich Business School at the University of East Anglia (UEA) and Athens University of Economics and Business (AUEB) have for the first time modelled the relationship between variations in leasing and selling market prices, using almost 10 years of data from the US, the world’s largest automobile market. They suggest that in order to determine more accurately the monthly payments agreed in leasing contracts, firms need to take into account the prevailing selling, also known as cash, price of vehicles.For households in developed countries the car is typically the second largest asset purchased after a house, and in the US a third of all cars sold are financed via leasing. The study, published this week in the Journal of Banking and Finance, finds that when selling prices go up in one month leasing rates tend to go down in the following months.Despite its importance, the link between leasing and selling markets for vehicles is not yet fully understood and the standard way companies calculate leasing rates ignores any interactions between the two. The researchers say this could lead to customers paying significantly more or less a month, while the firms could be incurring losses rather than making a profit. To address this problem they have developed a new pricing approach for lease vehicles, which allows changes in the selling market prices to have an effect on leasing market prices and vehicle values at the end of the contract.They use the example of a car worth $30,000 (USD) in the cash market which is leased for six months with a monthly finance rate of 1% and has a value of $25,000 at the end of the contract. Using actual market selling prices for a particular month, the traditional way of calculating the monthly instalment would result in the leasing firm undercharging by more than 40% per cent, or $466, a month. This is because selling prices increased significantly by over 1.5% that month and then leasing prices dropped, in line with the findings in the study, by a total of 2.61% over the next six months.Using the new model the study predicts a 1.77% decrease in lease prices over the six months and a lease payment calculation which is much closer to the fair price, since the difference is less than 5% or $73 a month. Although in this example consumers may seem to be better off, this is not the case when cash prices drop rather than increase, which is equally likely. Leasing firms may try to deal with the uncertainty in leasing rates and their profits by charging higher monthly instalments.Raphael Markellos, professor of finance at Norwich Business School, said: “The results suggest that we can make more accurate predictions about car leasing rates and residual values on the basis of cash prices. If the companies ignore this relationship, mistakes are more likely and sometimes these will benefit the consumer at the expense of the leasing firms, sometimes it will be the other way round. …


Read More: Link between selling, leasing market prices for cars studied

#Agriculture, #Alzheimer, #Economics, #King, #Professor, #School, #Science, #Standard

Researchers rejuvenate stem cell population from elderly mice, enabling muscle recovery

http://feeds.feedburner.com/~r/sciencedaily/top_news/top_health/~4/FbonCYSt4oo

Researchers at the Stanford University School of Medicine have pinpointed why normal aging is accompanied by a diminished ability to regain strength and mobility after muscle injury: Over time, stem cells within muscle tissues dedicated to repairing damage become less able to generate new muscle fibers and struggle to self-renew.”In the past, it’s been thought that muscle stem cells themselves don’t change with age, and that any loss of function is primarily due to external factors in the cells’ environment,” said Helen Blau, PhD, the Donald and Delia B. Baxter Foundation Professor. “However, when we isolated stem cells from older mice, we found that they exhibit profound changes with age. In fact, two-thirds of the cells are dysfunctional when compared to those from younger mice, and the defect persists even when transplanted into young muscles.”Blau and her colleagues also identified for the first time a process by which the older muscle stem cell populations can be rejuvenated to function like younger cells. “Our findings identify a defect inherent to old muscle stem cells,” she said. “Most exciting is that we also discovered a way to overcome the defect. As a result, we have a new therapeutic target that could one day be used to help elderly human patients repair muscle damage.”Blau, a professor of microbiology and immunology and director of Stanford’s Baxter Laboratory for Stem Cell Biology, is the senior author of a paper describing the research, which will be published online Feb. 16 in Nature Medicine. Postdoctoral scholar Benjamin Cosgrove, PhD, and former postdoctoral scholar Penney Gilbert, PhD, now an assistant professor at the University of Toronto, are the lead authors.The researchers found that many muscle stem cells isolated from mice that were 2 years old, equivalent to about 80 years of human life, exhibited elevated levels of activity in a biological cascade called the p38 MAP kinase pathway. This pathway impedes the proliferation of the stem cells and encourages them to instead become non-stem, muscle progenitor cells. …


Read More: Researchers rejuvenate stem cell population from elderly mice, enabling muscle recovery

#Baxter, #Biology, #Map, #Nature, #Pregnancy, #Professor, #Science, #Standard

Mobile compression device recommended to prevent DVT after joint surgery

http://feeds.feedburner.com/~r/sciencedaily/living_well/~4/lxSiE4Ew1Tc

Research from The Shiley Center for Orthopaedic Research and Education at Scripps Clinic could change how patients are treated to prevent blood clots after joint replacement surgery. A study published today as the lead article in the Journal of Bone and Joint Surgery determined that after lower extremity joint replacement surgery a mobile compression device was just as effective as blood thinners in preventing deep vein thrombosis (DVT), but without negative side effects including bleeding complications.The multicenter study, led by Scripps Clinic orthopedic surgeon Clifford Colwell, MD evaluated the efficacy of a mobile compression device that is small and portable enough for patients to use at home for 10 days or longer after joint replacement surgery.”Blood thinners have long been considered the standard of care to prevent blood clots after orthopedic surgery, but they can have side effects that are concerning for many patients,” said Dr. Colwell. “Through this research we have found and established an equally effective means of accomplishing the same goal with an added layer of safety for patients.”Story Source:The above story is based on materials provided by Scripps Health. Note: Materials may be edited for content and length.


Read More: Mobile compression device recommended to prevent DVT after joint surgery

#Agriculture, #Alternative-Medicine, #Clifford, #Education, #Health, #Safety, #Shileycenter, #Standard

Oil composition boost makes hemp a cooking contender

http://feeds.feedburner.com/~r/sciencedaily/plants_animals/agriculture_and_food/~4/sgyyb-YQn38

Scientists at the University of York today report the development of hemp plants with a dramatically increased content of oleic acid. The new oil profile results in an attractive cooking oil that is similar to olive oil in terms of fatty acid content having a much longer shelf life as well as greater heat tolerance and potentially more industrial applications.Researchers in the Centre for Novel Agricultural Products (CNAP) in the Department of Biology at York say that high oleic acid varieties are a major step towards developing hemp as a commercially attractive break crop for cereal farmers. The research is published in Plant Biotechnology Journal.Using fast-track molecular plant breeding, the scientists selected hemp plants lacking the active form of an enzyme involved in making polyunsaturated fatty acids. These plants made less poly-unsaturated fatty acids and instead accumulated higher levels of the mono-unsaturated oleic acid. The research team used conventional plant breeding techniques to develop the plants into a “High Oleic Hemp” line and higher oleic acid content was demonstrated in a Yorkshire field trial.Oil from the new line was almost 80 per cent oleic acid, compared with typical values of less than 10 per cent in the standard hemp line. This high mono-unsaturated/low poly-unsaturated fatty acid profile increases the oil’s thermal stability and oil from the new line was shown to have around five times the stability of standard hemp oil. This not only makes the oil more valuable as a cooking oil but also increases its usefulness for high temperature industrial processes.As oilseed rape faces declining yields and increasing attacks from pest and disease, UK farming needs another break crop to ensure the sustainability of its agriculture and maintain cereal yields. An improved hemp crop, yielding high quality oil would provide an excellent alternative. Hemp is a low-input crop and is also dual-purpose, with the straw being used as a fibre (for bedding, composites and textiles), for biomass and as a source of high value waxes and secondary metabolites.Professor Ian Graham, from CNAP, said: “The new line represents a major improvement in hemp as an oil crop. Similar developments in soybean and oilseed rape have opened up new markets for these crops, due to the perceived healthiness and increased stability of their oil.”In 2014 field trials of the new High Oleic Hemp are being rolled out across Europe in order to establish agronomic performance and yield under a range of environmental conditions in advance of launching a commercial crop.Story Source:The above story is based on materials provided by University of York. …


Read More: Oil composition boost makes hemp a cooking contender

#Agriculture, #Biotechnology, #Centre, #Department, #Development, #Europe, #Major, #Plant, #Pregnancy, #Research, #Standard, #York