Elderly men with self-reported sleep disturbances run a higher risk of developing Alzheimer's disease than men without self-reported sleep disturbances, says a study.

"We demonstrate that men with self-reported sleep disturbances run a 1.5-fold higher risk to develop Alzheimer's disease than those without reports of sleep disturbances during a 40-year follow-up period," said lead researcher Christian Benedict from Uppsala University in Sweden.

"The later the self-reported sleep disturbance was found the higher the risk was for developing Alzheimer's disease," Benedict added.

The researchers followed more than 1,000 men, who were initially 50 year old, between the years 1970 and 2010.

The data suggest that a regular good night's sleep could support brain health in men.

"These findings suggest that strategies aimed at improving sleep quality in late life may help reduce the risk to develop Alzheimer's disease," Benedict pointed out.

The researchers also pointed out that several lifestyle factors, such as exercise, can influence the brain's health.

"Thus, it must be borne in mind that a multifaceted lifestyle approach comprising good sleep habits is essential for maintaining brain health as you age", Benedict stressed.

The results appeared in the journal Alzheimer's & Dementia.

In a new study, scientists have discovered how dietary cocoa flavanols, the naturally occurring bioactives found in cocoa, reverse age-related memory decline in healthy older people.

The study led by Columbia University Medical Center (CUMC) scientists, provided the first direct evidence that one component of age-related memory decline in humans was caused by changes in a specific region of the brain and that such a form of memory decline could be improved by a dietary intervention.

Previous work had shown that changes in a specific part of the brain-the dentate gyrus-were associated with age-related memory decline. To see if the dentate gyrus was the source of age-related memory decline in humans, senior author Dr. Scott A. Small and his colleagues tested whether compounds called cocoa flavanols could improve the function of this brain region and improve memory. Flavanols extracted from cocoa beans had previously been found to improve neuronal connections in the dentate gyrus of mice.

In the CUMC study, 37 healthy volunteers, ages 50 to 69, were randomized to receive either a high-flavanol diet (900 mg of flavanols a day) or a low-flavanol diet (10 mg of flavanols a day) for three months. Brain imaging and memory tests were administered to each participant before and after the study. The brain imaging measured blood volume in the dentate gyrus, a measure of metabolism, and the memory test involved a 20-minute pattern-recognition exercise designed to evaluate a type of memory controlled by the dentate gyrus.

The high-flavanol group also performed significantly better on the memory test. Dr. Small said that if a participant had the memory of a typical 60-year-old at the beginning of the study, after three months that person on average had the memory of a typical 30- or 40-year-old. He cautioned, however, that the findings needed to be replicated in a larger study.

Flavanols are also found naturally in tea leaves and in certain fruits and vegetables, but the overall amounts, as well as the specific forms and mixtures, vary widely.

The precise formulation used in the CUMC study had also been shown to improve cardiovascular health. Brigham and Women's Hospital in Boston recently launched an NIH-funded study of 18,000 men and women to see whether flavanols can help prevent heart attacks and strokes.

The researchers pointed out that the product used in the study is not the same as chocolate, and they caution against an increase in chocolate consumption in an attempt to gain this effect.

In the study, the researchers were unable to assess whether exercise had an effect on memory or on dentate gyrus activity.

The study is published in the advance online issue of Nature Neuroscience.

A new research has identified that 'megakaryocytes' or 'megacells' are responsible for playing a critical role in adult stem cell transplant.

Hematopoietic stem cells differentiate to generate megakaryocytes in bone marrow and the study has shown that the hematopoietic stem cells (the parent cells) could be directly controlled by their own progeny (megakaryocytes).

The results had suggested that megakaryocytes might be used clinically to facilitate adult stem cell regeneration and to expand cultured cells for adult stem cell transplants.

Researchers at Stowers Institute for Medical Research had discovered that megakaryocytes had directly regulated the function of murine hematopoietic stem cells-adult stem cells that had formed the blood and immune cells and that had constantly renewed the body's blood supply. These cells could also develop into all types of blood cells, including white blood cells, red blood cells, and platelets.

Because of their remarkable ability to renew themselves and differentiate into other cells, hematopoietic stems cells have been used to treat many diseases and conditions. The transplantation of isolated human hematopoietic stem cells has been used in the treatment of anemia, immune deficiencies and other diseases, including cancer.

The study was published in the journal Nature Medicine.

A new study has demonstrated that people who are physically active three times a week are less likely to go under depression.

The study conducted at University College London (UCL) showed that people who increased their weekly activity reported fewer depressive symptoms but those with more depressive symptoms were less active, particularly at younger ages.

Researchers followed 11,135 people born in 1958 up until the age of 50, recording depressive symptoms and levels of physical activity at regular intervals in adulthood. They found that each additional activity session per week reduced odds of depression by 6 percent. In England 19 percent of men and 26 percent of women were currently classed as "inactive', and this study suggested that activity could significantly improve their mental as well as physical health.

Dr Snehal Pinto Pereira of the UCL Institute of Child Health, lead author of the study, said that assuming the association was causal, leisure time physical activity had a protective effect against depression. If an adult between their twenties and forties who was not physically active became active 3 times per week, they would reduce their risk of depression by approximately 16percent.

The study showed that people who reported more depressive symptoms at age 23 tended to be less physically active, but this effect weakened as they grew older.

Professor Mark Petticrew of the London School of Hygiene and Tropical Medicine, Director of the Public Health Research Consortium, said that many people were already aware of the benefits of physical activity on their general health, but they were now seeing a growing body of evidence that suggested it also had a positive effect on a person's mental well-being.

The study is published in JAMA Psychiatry.

The preference for a high carbohydrate diet and acidic sports drinks during training and performance may explain the prevalence of poor dental health among athletes, says a study.

The impact of these contributing factors can be exacerbated by a dry mouth during performance.

Dental consultations accounted for almost a third of all medical visits at London 2012 Olympic Games, and that demand has continued to increase at subsequent major competitive events, the findings showed.

"With clear psycho-social impacts of oral health, it would be surprising if training and performance were not affected in those athletes with poor oral health," the researchers pointed out.

Athletes with poor dental health are likely to suffer pain, difficulties sleeping and eating, systemic inflammation, a dent to their confidence and may be generally out of sorts, all of which could be detrimental to their performance, the researchers suggested.

The researchers from Britain and North America conducted a thorough review of published evidence, including 39 studies on elite or professional sports and found that poor dental health is widespread.

Tooth decay (dental caries); gum disease (periodontal disease); enamel erosion and infected wisdom teeth (pericoronitis) /impacted molars were the most commonly reported problems.

Tooth decay affected 15-75 percent of athletes; moderate to severe gum disease up to 15 percent; enamel erosion 36-85 percent; and pericoronitis/impacted molars 5-39 percent.

Poor understanding of importance of good dental health on performance and training is also contributing to widespread dental problems among athletes, the study noted.

The study appeared in the British Journal of Sports Medicine.