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blood test used to determine whether a heart is suitable for donation may be leading to unnecessary rejections, and its use should be reviewed. This is the conclusion of a new study published in the journal Circulation: Heart Failure.
Heart failure occurs when the heart is unable to pump enough oxygen-rich blood around the body to help other organs function.
According to the Centers for Disease Control and Prevention (CDC), in the United States, around 5.7 million Americans have heart failure.
In some cases, heart failure can be treated with lifestyle changes - such as a healthy diet, exercise, and quitting smoking - and medications. For end-stage heart failure, however, a heart transplant may be the only option.
According to the United Network for Organ Sharing (UNOS), as of June 10, 2016, there are 4,147 people in the U.S. waiting for a heart transplant.
However, according to Dr. Snehal R. Patel, assistant professor of medicine at Albert Einstein College of Medicine's Montefiore Medical Center in New York, NY, more than half of these patients will not receive a transplant.
"A lot of focus has been on finding ways to sign up more people as organ donors, but there is also a problem in that only an average of 1 in 3 donor hearts are placed," he adds.
In many heart transplant centers, the blood of potential donors is routinely tested for levels of troponin I - a protein that is released in response to heart damage.
Dr. Patel explains that if troponin I levels are high, then a donor heart will often be rejected out of concern that the organ is too damaged to function following transplantation - regardless of whether the heart appears healthy.
Donor troponin I levels do not affect recipient survival
For their study, the researchers assessed the outcomes of 10,943 heart transplant recipients aged 18 and older using data from UNOS. All donor hearts had normal pumping function, the authors note.
The team set out to determine whether there are any differences in outcomes for patients who received a heart from a donor with high troponin I levels.
At 30 days, 1 year, 3 years, and 5 years after heart transplantation, the researchers found no significant differences in survival between recipients whose donors had high troponin I levels and those whose levels were normal.
There was also no association between donor troponin I levels and risk of recipient death 1 year after transplantation, the researchers report.
Additionally, donor troponin I levels made no difference to recipients' incidence of primary graft failure - loss of pumping action that occurs within 30 days of transplantation - and cardiac allograft vasculopathy - a form of heart disease that can limit long-term survival following heart transplantation.
Based on their findings, Dr. Patel and colleagues believe heart transplant centers should make decisions about whether a heart is suitable for transplantation based exclusively on donor troponin I levels.
Dr. Norelle Reilly, of the Division of Pediatric Gastroenterology and the Celiac Disease Center at Columbia University Medical Center in New York, NY, has been looking into some issues relating to the gluten-free diet (GFD).
Her commentary is published in The Journal of Pediatrics.
Celiac disease (CD) is an autoimmune disease. A person who has CD cannot eat gluten, a protein found in wheat, rye, and barley.
Doing so can have serious consequences, as it can trigger an immune response that may damage the small intestine or other parts of the digestive system. Irritability and depression are common symptoms.
CD is a genetic condition, and the only treatment is to avoid gluten.
In 2015, around 0.5 percent of Americans were following a strict GFD, 25 percent reported consuming gluten-free foods, and between 15-21 percent rated "gluten-free" as "very important" when buying food.
In contrast, a market survey in 2013 indicated that 31 percent of Americans considered the diet "a fad." By 2015, 47 percent shared this view.
What is a gluten-free diet?
People who have to avoid gluten cannot eat anything containing wheat, barley, or rye flour, and some cannot eat oats.
They must avoid bread, pasta, cakes, cookies, or crackers, and should consume no sauces or gravies thickened with flour, among other items. Alternatively, they can choose gluten-free (GF) versions.
Gluten occurs in some unexpected items, such as luncheon meat, soy sauce, and rice mixes, in some flavorings and preservatives, and in certain medications. A person with CD must check the labels carefully.
Safe foods include meat, fish, fruit, vegetables, rice, potatoes, lentils, and natural seeds and nuts. Specially prepared breads, cakes, cookies, and ready meals are now widely available.
Why go gluten-free?
In 2015, a survey asked 1,500 Americans why they had chosen to "go gluten-free."
Results showed that 35 percent had "no reason" for doing so, 26 percent said it was a "healthier option," and 19 percent wanted to improve their "digestive health." Ten percent had someone in the family with a gluten sensitivity, and 8 percent had a gluten sensitivity.
According to Dr. Reilly, "Out of concern for their children's health, parents sometimes place their children on a gluten-free diet in the belief that it relieves symptoms, can prevent CD, or is a healthy alternative without prior testing for CD or consultation with a dietitian."
She calls for clearer information about the GFD because of "frequent misunderstanding" about gluten.
Misconceptions about the GFD
Dr. Reilly raises a number of issues and misconceptions about avoiding gluten.
One is that it offers a healthy lifestyle choice with no disadvantages.
In fact, Dr. Reilly points out, there is no proven benefit of avoiding gluten, unless a person has CD or a wheat allergy.
She adds that avoiding gluten could mean a higher fat and calorie intake, because packaged GF goods often contain more fat and sugar than their conventional counterparts, potentially contributing to obesity and prediabetes.
Avoiding gluten can also lead to nutritional deficiencies, especially of the B vitamins, folate, and iron, because GF products often lack fortification.
A further belief is that gluten is toxic, but Dr. Reilly notes that no evidence supports this theory. In fact, over-dependence on rice, she suggests, could mean an increased intake of arsenic, which rice has a tendency to absorb.
Some people have a close relative with CD, and they avoid gluten through fear of developing it themselves. Dr. Reilly points out that healthy relatives of people with CD do not need to avoid gluten, and nor do healthy infants who are at risk of developing CD.
What if the GFD is necessary?
A few people will be healthier and have a better quality of life with a GFD, says Dr. Reilly, but they need guidance from an experienced, registered dietitian.
She points out that CD is not the only reason to avoid gluten. Doing so can help relieve symptoms in people with a wheat sensitivity or wheat allergy.
However, there is no scientific evidence that avoiding gluten is better for a child with no confirmed diagnosis of CD or wheat allergy, and doing so could obscure a diagnosis of CD.
A GFD can add to the family budget, as GF products tend to be more costly. Inconvenience and social isolation have been reported by children, says the commentary.
In this sense, a GFD could mean a lower quality of life, potentially posing more risk than benefit.
WEDNESDAY, March 2, 2016 (HealthDay News) -- Prostate cancer may be more aggressive in men who are deficient in vitamin D, new research suggests.
A study of nearly 200 men having their prostate removed found those with low vitamin D levels were more likely to have rapidly growing tumors than those with normal levels of the "sunshine" vitamin.
"If men with vitamin D deficiency are more likely to have [more advanced disease] at the time of prostate surgery, then perhaps men should be tested for this when they are diagnosed with prostate cancer and subsequently supplemented with vitamin D if they are deficient," said researcher Dr. Adam Murphy. He is an assistant professor of urology at Northwestern University in Chicago.
However, another expert isn't ready to go that far.
This study can't prove that vitamin D deficiency causes aggressive prostate cancer, only that the two are associated, said Dr. Anthony D'Amico, chief of radiation oncology at Brigham and Women's Hospital in Boston.
But D'Amico thinks the results are important enough to spur further study into the possible connection between vitamin D and prostate cancer. "It's a hypothesis that's worth testing," he said.
For now, though, D'Amico doesn't think enough evidence exists to recommend vitamin D supplements to prevent prostate cancer or make it less aggressive.
Murphy said he has been exploring the link between prostate cancer and vitamin D for some time. He said racial distinctions were noted in this study, too, with black men having more aggressive tumors and lower vitamin D levels than white men.
These findings suggest that one reason black men have higher odds of developing -- and dying of -- prostate cancer is because of their "higher propensity for having vitamin D deficiency from the sun-blocking effects of melanin and perhaps dietary intake differences," Murphy said. The study could not prove this, however.
The human body gets vitamin D from certain foods. These include fortified products (such as milk, orange juice and cereal), and certain fish (such as salmon), according to the U.S. National Institutes of Health. The body also makes the vitamin when the skin is exposed to sunlight. Dark-skinned people have more melanin, which prevents burning.
Murphy said men with dark skin, low vitamin D intake or low sun exposure should be tested for vitamin D deficiency when diagnosed with prostate cancer or elevated PSA (prostate specific antigen), which is associated with the cancer. He believes supplementation is warranted for those with low vitamin D levels.
The study included 190 men having prostate surgery. The researchers found that nearly 46 percent of the men had aggressive cancer, and these men had vitamin D levels about 16 percent lower than men with slower-growing tumors.
After accounting for age, PSA levels and abnormal rectal exams, Murphy and his colleagues found that vitamin D levels below 30 nanograms per milliliter (ng/mL) of blood were linked to higher odds of aggressive prostate cancer.
The National Myelodysplastic Syndromes Natural History Study (The National MDS Study) is underway, the ECOG-ACRIN Cancer Research Group and its collaborators announced today. This new study, funded by the National Institutes of Health's National Heart, Lung, and Blood Institute (NHLBI), and performed in collaboration with the National Cancer Institute (NCI), will collect detailed information and biological samples from 2000 adults with myelodysplastic syndromes (MDS) and 500 more patients receiving care for a persistent low red blood cell count (anemia) that cannot be explained. Its purpose is to build a national resource to be used by scientists in future research.
A third group will be formed as a comparison cohort by selecting 1000 patients who will be screened in the study because of symptoms of MDS, but who will be found to not actually have one of the blood disorders. In total, the study will enroll up to 3500 patients, making it the largest-ever prospective study of MDS in the U.S.
It is hoped that this national resource will help researchers to identify the causes and genetic makeup of these serious and sometimes fatal diseases. Other research could lead to new and better ways to diagnosis and treat these conditions.
MDS occur when the blood-forming cells in the bone marrow are damaged and have problems making new blood cells. Considered a type of cancer, these abnormal blood cells fail to grow properly and die sooner than normal cells, leaving affected individuals with low blood counts and a shorter lifespan. Treatment options depend on the disease severity at diagnosis and are limited in their effectiveness.
About 30,000 people every year develop MDS, which occur mostly in adults over 60 years of age and more often in men than women. Common symptoms of MDS include fatigue, unusual bleeding, bruises, and tiny red marks under the skin, paleness, and shortness of breath.
Many people with MDS develop a serious or life-threatening anemia. About one-third of people with MDS develop acute myeloid leukemia, an aggressive blood cancer.
There are many questions about the causes of MDS and what patients can expect during the course of the disease. Unfortunately, MDS lacks a large collection of patient-related disease information and human tissue samples, such as diseased blood and bone marrow samples, which provide the opportunity for scientific research and breakthroughs. Such resources are already in place for other more common diseases, but not yet for MDS.
This study requires the participation of a large network of physicians who support medical research and who examine people experiencing the symptoms of MDS. A number of organizations are collaborating on this effort. For patient recruitment, which is expected to take five to seven years, the NCI is contributing access to its two large cancer research networks, the NCI National Clinical Trials Network (NCTN) and the NCI Community Oncology Research Program (NCORP).
Physicians may enroll their patients in this study if they and their hospital, practice, or cancer center are a member of any cancer research group that belongs to either NCI network. These groups are the Alliance for Clinical Trials in Oncology, ECOG-ACRIN Cancer Research Group, NRG Oncology, and SWOG.
ECOG-ACRIN Cancer Research Group, which is leading the study, has added The National MDS Study to its portfolio of active clinical trials in leukemia, thus streamlining its implementation at clinical centers nationwide.
Patients' blood, bone marrow, and other body tissues will be processed and stored at a central laboratory and biorepository at the Moffitt Cancer Center and its M2Gen subsidiary in Tampa, Fla. Patient information and data from patient samples will be linked and stored centrally at a data coordinating center, under the supervision of The Emmes Corporation, which is coordinating the trial.
At the end of this study, the collected data and specimens will be transferred to the NHLBI and will be available to scientists throughout the country for their own research studies. In this way, The National MDS Study will enable scientists to answer questions about MDS that up to this point have been impractical to study at a single institution or even among small groups of researchers.
Recent years have brought more attention to the role of carbohydrates in our diets and the differences between healthy and unhealthy carbs, most often in the context of weight control. A new study highlights one more reason to avoid sugary beverages, processed foods and other energy-dense carbohydrate-containing foods—cutting them may help reduce your risk of cancer.
In the new study, regular consumption of sugary beverages was associated with a 3 times greater risk of prostate cancer and higher intake of processed lunch foods such as pizza, burgers and meat sandwiches doubled prostate cancer risk. By contrast, healthy carbohydrate-containing foods like legumes, non-starchy vegetables, fruits and whole grains were collectively associated with a 67 percent lower risk for breast cancer.
"One of the most important findings here is that the type of carbohydrate-containing foods you consume can impact your cancer risk," said Nour Makarem, a Ph.D. student at New York University and the study's lead author. "It appears that healthy carbohydrate sources, such as legumes, tend to protect us from cancer, but non-healthy ones, such as fast foods and sugary beverages, seem to increase the risk of these cancers."
Makarem will present the research at the American Society for Nutrition Scientific Sessions and Annual Meeting during Experimental Biology 2016.
The study is based on the health records of 3,100 volunteers tracked since the early 1970s. Researchers began tracking participants' diets through detailed food frequency questionnaires starting in 1991. For the new study, Makarem and her colleagues categorized all of the study participants' food sources by glycemic index—a measure of dietary carbohydrate quality based on an item's relative impact on blood sugar levels as compared to a reference food—and glycemic load, a measure of both the quantity and quality of carbohydrates in a given food item. They then analyzed the results in relation to volunteers' cancer rates.
After taking into account multiple cancer risk factors, the study found that eating foods with a higher glycemic load was associated with an 88 percent higher prostate cancer risk. Prostate cancer is one of the most common types of cancer and the second leading cause of cancer-related death in men.
"Our study showed very strong associations between certain foods and cancer, in particular with prostate cancer," said Makarem. "There had not been very many studies on food sources and prostate cancer previously."
"Americans consume almost half of their added sugars in beverages," said Makarem. "Sugar-sweetened beverages have been shown to increase the risk of obesity and diabetes, and our study documents that they may also have a detrimental impact on cancer risk."
By contrast, consuming low-glycemic index foods such as legumes, non-starchy vegetables, most fruits and whole grains was associated with a 67 percent lower breast cancer risk. Breast cancer risk was also reduced among women who had a higher level of carbohydrate intake overall as a proportion of their total calories. However, in this study participants with in the highest level of carbohydrate intake also had higher intakes of fruits and vegetables, whole grains and legumes. These findings underscore the idea that the type of carbohydrates matters more than the total amount of carbohydrates, said Makarem.
Among individual foods, legumes such as beans, lentils and peas were associated with 32 percent lower risk of all overweight- and obesity-related cancers, including breast, prostate and colorectal cancers.
By nature of the study design, the results point only to associations, not necessarily to cause-and-effect. Nonetheless, the findings are in line with previous studies, which have shown that malignant cancer cells seem to feed on sugar, and that diets high in refined carbohydrates may lead to a range of adverse health effects primarily due to their impacts on body fatness and on the dysregulation of insulin and glucose, both of which are factors that may increase cancer risk.
"Current cancer prevention guidelines recommend avoiding sugary drinks and limiting the consumption of energy-dense foods, which tend to be high in refined carbohydrates," said Makarem. "I think our findings add to the body of evidence behind this recommendation and strengthen the associations between these types of food and cancer."
One caveat that Makarem noted is that the volunteers involved in the study were 99 percent Caucasian. Further study is needed to determine if these associations hold true in more ethnically-diverse groups.
Adult stem cells provide the body with a reservoir from which damaged or used up tissues can be replenished. In organs like the intestines and skin, which need constant rejuvenating, these stem cells are dividing frequently. But in other body structures, including the hair follicles, they are held in a quiescent state--one in which they don't reproduce until they receive signals from their surroundings that it's time to regenerate.
It makes intuitive sense that stem cells, being such a valuable resource, would be used sparingly. Yet scientists have limited understanding of how their quiescence is regulated, and are even unsure of its precise biological function. In a study published recently in PNAS, Elaine Fuchs, Rebecca C. Lancefield Professor and head of the Robin Chemers Neustein Laboratory of Mammalian Cell Biology and Development, and Kenneth Lay, a graduate student in her lab, report on new insights into the biological signals that make hair follicle stem cells oscillate between states of quiescence and regenerative activity.
"In an earlier study, my lab showed that when mice age, the old fat in their skin produces higher levels of a secreted signal, called BMP," Fuchs says. "This signal acts as a molecular brake on the hair follicle stem cells, causing them to spend much longer times in quiescence."
In the present study, Lay identified a stem cell gene that is activated by BMP signaling, and showed that when this gene is missing, the stem cells grow hairs with dramatically shorter intervals. "We thought initially that the key to hair growth might be the fountain of youth," Fuchs says, "but the mice's hair coat surprisingly thinned and greyed precociously."
More growth and fewer bulges
Usually the stem cells then create a new bulge along with the new hair, while ensuring that the old bulge and the old hair stay put in the hair follicle. Only the new bulge can make another new hair, but the old bulge is kept in place to maintain a thick and lush coat. In mice, hair follicles can accumulate up to four of these bulges.
When Lay and Fuchs created mice that lack FOXC1--by disabling or "knocking out" the gene that produces this protein--they observed that the animals' hair follicle stem cells spent more time growing hairs and less time in quiescence. Over the course of nine months, while hair follicles from normal mice grew four new hairs, those from the FOXC1 knockout mice had already made new hairs seven times. "The knockout stem cells enter an overactive state in which they can't establish quiescence adequately," explains Lay.
The researchers also found that in the absence of FOXC1, hair follicles always had only one hair despite having made new hairs seven times. This is because these hair follicles could not retain their old bulges, though they generated a new bulge without a problem. As the stem cells started proliferating more, they became less able to stick together. As a result, their old bulges did not stay properly tethered to the hair follicle when the newly growing hair pushed past it. And since the bulge emits quiescence signals, its loss activated the remaining stem cells even faster.
Going grey and going bald
While the hair follicle stem cells of FOXC1-deficient mice produce hairs at a relatively breakneck pace, this profligate growth seems to wear them out. Older knockout mice had sparser, greyer coats, and they could not regenerate their fur as quickly as their normal age-matched or younger peers. A similar phenomenon has been described in mouse hematopoietic stem cells, which give rise to blood cells--those stem cells that are more active in young animals appear to become exhausted as the animals grow older.
"Hair follicle stem cells influence the behavior of melanocyte stem cells, which co-inhabit the bulge niche," explains Fuchs. "Thus, when the numbers of hair follicle stem cells declined with age, so too did the numbers of melanocyte stem cells, resulting in premature greying of whatever hairs were left." Not much is known about naturally occurring hair loss with age, but these balding knockout mice may provide a model to study it.
Vitamin B1 is a vital human nutrient that belongs to the Vitamin B complex. It plays an important role in maintaining a healthy nervous system and improving the cardiovascular functioning of the body.
Vitamin B1 is one of the eight water-soluble vitamins in the B complex family. It helps in the conversion of carbohydrates into glucose, which in turn is used to produce energy for carrying out various bodily functions. Vitamin B1 is also required for the breakdown of fats and protein.
In addition to these health benefits, it maintain the muscle tone along the walls of the digestive tract and promotes the health of the nervous system, skin, hair, eyes, mouth, and liver. It also improves the body’s ability to withstand stress and is often called the “anti-stress” vitamin.
Important Sources of Vitamin B1
Some of the early symptoms of deficiency might include lethargy, irritability, loss of memory, loss of sleep or appetite, weight loss, indigestion or constipation, and calf muscle tenderness. If left untreated these initial symptoms might lead to a more severe form of thiamin deficiency, known as beriberi. This condition is characterized by nerve, heart, and brain abnormalities, but the symptoms might vary in every person and depends on a number of factors. Some more examples are explained below.
Dry Beriberi: This condition might involve nerve and muscle abnormalities, a prickling sensation in the toes, a burning sensation in the feet at night, leg cramps and muscle atrophy.
Wet Beriberi: Common symptoms might include abnormally fast heart beat, fluid retention in the legs, pulmonary edema, and hypotension, which might result in shock and even death.
CerealBrain Abnormalities: In alcoholics, thiamin deficiency might result in brain abnormalities such as Wernicke-Korsakoff syndrome. Some of its common symptoms include haziness, involuntary eye movements, difficulty in walking and partial paralysis of the eyes among other debilitating symptoms. If ignored, these symptoms could become fatal. Some of the common symptoms of Korsakoff’s psychosis include loss of memory, incoherence and confabulation.
Infantile Beriberi: This variety is commonly seen in newborn children of women already suffering from thiamin deficiency who contract this condition from the mother’s milk. Heart failure, loss of reflexes and aphonia are some of the common symptoms, so be sure to have sufficient levels of vitamin B1 if you are pregnant.
Observational studies have linked lower omega-3 (n-3) polyunsaturated fatty acids (PUFAs) and higher omega-6 (n-6) PUFAs with inflammation and depression, but randomized controlled trial (RCT) data have been mixed. To determine whether n-3 decreases proinflammatory cytokine production and depressive and anxiety symptoms in healthy young adults, this parallel group, placebo-controlled, double-blind 12-week RCT compared n-3 supplementation with placebo. The participants, 68 medical students, provided serial blood samples during lower-stress periods as well as on days before an exam. The students received either n-3 (2.5g/d, 2085mg eicosapentaenoic acid and 348mg docosahexanoic acid) or placebo capsules that mirrored the proportions of fatty acids in the typical American diet. Compared to controls, those students who received n-3 showed a 14% decrease in lipopolysaccharide (LPS) stimulated interleukin 6 (IL-6) production and a 20% reduction in anxiety symptoms, without significant change in depressive symptoms. Individuals differ in absorption and metabolism of n-3 PUFA supplements, as well as in adherence; accordingly, planned secondary analyses that used the plasma n-6:n-3 ratio in place of treatment group showed that decreasing n-6:n-3 ratios led to lower anxiety and reductions in stimulated IL-6 and tumor necrosis factor alpha (TNF-α) production, as well as marginal differences in serum TNF-α. These data suggest that n-3 supplementation can reduce inflammation and anxiety even among healthy young adults. The reduction in anxiety symptoms associated with n-3 supplementation provides the first evidence that n-3 may have potential anxiolytic benefits for individuals without an anxiety disorder diagnosis. ClinicalTrials.gov identifier: NCT00519779.
Study coauthor Dr. Nancy Turner, of the Department of Nutrition and Food Science at Texas A&M University, and colleagues say their findings may have important implications for individuals heavily exposed to ionizing radiation.
These include cancer patients undergoing radiotherapy, astronauts, radiation workers and victims of nuclear accidents.
"Bone loss caused by ionizing radiation is a potential health concern for those in occupations or in situations that expose them to radiation," Dr. Turner explains.
"The changes in remodeling activity caused by exposure to radiation can lead to impaired skeletal integrity and fragility both in animals and human radiotherapy patients."
In humans, bone loss can lead to osteoporosis - a disease in which the bones become more brittle, fragile and more vulnerable to breakage. It is estimated that osteoporosis is responsible for more than 8.9 million fractures worldwide each year.
For the study, the researchers set out to investigate a number of strategies that they believed could tackle the underlying mechanisms that contribute to ionizing radiation-related bone damage, such as radiation-induced oxidative stress.
Dried plums reduced gene expression linked to bone breakdown
The team tested a number of different antioxidant and anti-inflammatory interventions on mice that were exposed to ionizing radiation, assessing the effects the interventions had on the expression of genes linked to the breakdown of bone, as well as their effects on bone loss.
The interventions included a cocktail consisting of five different antioxidants (ascorbic acid, N-acetyl cysteine, L-selenomethionine, dihydrolipoic acid and vitamin E), dihydrolipoic acid, ibuprofen and dried plum.
The team found that dried plum was most effective for reducing expression of the genes Nfe2l2, Rankl, Mcp1, Opg and TNF-α, which are related to the breakdown of bone. Dried plum was also most effective for preventing later bone loss induced by ionizing radiation.
While the researchers are unable to explain the exact reasons why dried plums appear to protect bones from damage caused by ionizing radiation, they note that the fruit contains a number of polyphenols - including gallic acid, caffeoyl-quinic acids, coumaric acid and rutin - that have antioxidant and anti-inflammatory properties.
"Dried plums contain biologically active components that may provide effective interventions for loss of structural integrity caused by radiotherapy or unavoidable exposure to space radiation incurred over long-duration spaceflight," says Dr. Turner, adding: