Scientists Disarm HIV in Step Towards Vaccine

Researchers have found a way to prevent HIV from damaging the immune system, in a new lab-based study published in the journal Blood. The research, led by scientists at Imperial College London and Johns Hopkins University, could have important implications for the development of HIV vaccines.
HIV/AIDS is the third biggest cause of death in low income countries, killing around 1.8 million people a year worldwide. An estimated 2.6 million people became infected with HIV in 2009.
The research shows that HIV is unable to damage the immune system if cholesterol is removed from the virus's membrane. Usually, when a person becomes infected, the body's innate immune response provides an immediate defence. However, some researchers believe that HIV causes the innate immune system to overreact and that this weakens the immune system's next line of defence, known as the adaptive immune response.
In the new study, the researchers removed cholesterol from the membrane surrounding the virus and found that this stopped HIV from triggering the innate immune response. This led to a stronger adaptive response, orchestrated by immune cells called T cells. These results support the idea that HIV overstimulates the innate response and that this weakens the immune system.
Dr Adriano Boasso, first author of the study, from Imperial College London, said: "HIV is very sneaky. It evades the host's defences by triggering overblown responses that damage the immune system. It's like revving your car in first gear for too long. Eventually the engine blows out.
"This may be one reason why developing a vaccine has proven so difficult. Most vaccines prime the adaptive response to recognise the invader, but it's hard for this to work if the virus triggers other mechanisms that weaken the adaptive response."
HIV takes its membrane from the cell that it infects. This membrane contains cholesterol, which helps to keep it fluid. The fluidity of the membrane enables the virus to interact with particular types of cell. Cholesterol in the cell membrane is not connected to cholesterol in the blood, which is a risk factor for heart disease but is not linked to HIV.
Normally, a subset of immune cells called plasmacytoid dendritic cells (pDCs) recognise HIV quickly and react by producing signalling molecules called interferons. These signals activate various processes which are initially helpful, but which damage the immune system if switched on for too long.
In collaboration with researchers at Johns Hopkins University, the University of Milan and Innsbruck University, Dr Boasso's group at Imperial have discovered that if cholesterol is removed from HIV's envelope, it can no longer activate pDCs. As a consequence, T cells, which orchestrate the adaptive response, can fight the virus more effectively.
The researchers removed cholesterol using varying concentrations of beta-cyclodextrin (bCD), a derivative of starch that binds cholesterol. Using high levels of bCD they produced a virus with a large hole in its envelope. This permeabilised virus was not infectious and could not activate pDCs, but was still recognised by T cells. Dr Boasso and his colleagues are now looking to investigate whether this inactivated virus could be developed into a vaccine.
"It's like an army that has lost its weapons but still has flags, so another army can recognise it and attack it," he said.
The research was funded by the Wellcome Trust and the National Institutes of Health.

Courtesy: Science Daily

Exercise produces crosstalk between bone, fat and Pancreatic Cells

Pancreas

Washington, Sept 20 : Exercise can produce healthy chatter between bones, fat and pancreatic cells in humans, thereby helping them in bringing out the best in each other, researchers say.
A small study of obese children enrolled in after-school exercise programs showed 12 weeks of vigorous exercise resulted in stronger bones, improved insulin sensitivity (reduced diabetes risk) and less of the most-deadly belly, or visceral, fat, Georgia Health Sciences University researchers report.
It also indicated that blood levels of the hormone osteocalcin, made by bone-producing osteoblasts, might be a good indicator of how things are going in all three areas, said Dr. Norman Pollock, bone biologist at GHSU's Georgia Prevention Institute.
Pollock's finding is some of the earliest human evidence of this crosstalk among the divergent cell types.
"The idea is that bones can possibly sense environmental stimuli such as being physically active or sedentary and dictate energy regulation accordingly," he said.
The reality is bones get bigger and stronger with exercise and they appear to be sharing the good news. "When osteocalcin is released in your blood, that hormone is talking back to the adipocytes, the cells that store fat, and the pancreatic cells that release insulin to improve energy metabolism."
Bone researchers like Pollock have previously believed bones were just listening.
The study was presented at the American society's annual September meeting in San Diego.

Courtesy: ANI

Men Also Can be affected by Breast Cancer

Although beast cancer have affected most women, but men also can suffer from the disease. Male breast anatomy is no different with women. But men have more testosterone which can suppress breast development. Therefore, the breast tissue is dominated only by channels that do not develop and a small amount of fat
However, under certain conditions, male breasts can be enlarged due to the consumption of drugs such as antibiotics, marijuana, heroin, antidepressants, amphetamines, and AIDS therapy. Breast enlargement or gynecomastia may also occur when men experience hormonal imbalance and obesity.
Because of their organ are similar with women, breast cancer disease could also threaten a man. The high Estrogen levels are risk for developing breast cancer cells. Female sex hormone or estrogen stimulates breast cells and divide actively in large numbers. Many cells are damaged and this damage to genes that cause cancer. The initial symptoms of this disease usually are in the form of a lump or pain in the chest. “Breasts are harder and nipples become sore,” said plastic surgeon, Enrina Diah.
The man still lay with the disease. They often ignore the symptoms. Many men knew that they suffered from the disease in the elderly. According to the nonprofit Breastcancer.org, this disease attacked men less than one percent of all breast cancer diagnoses in women.
Mammography can be the initial technique for diagnosing breast cancer. If a mass is found in this examination, the doctor will perform a biopsy to take sample of the bump. Surgery or the lump removal is often being the priority choice to stop the spread locally in the nipple or skin.
Male breast cancer is extremely uncommon and just covers 1% of all breast cancers. For men, between the ages of 60 and 70 is the most common age to get this cancer type. It is About 1,990 new cases were detected in the US in 2008, and will lead to 480 deaths, as said by the American Cancer Society. And about 40,000 females die yearly from this dreadful cancer.
It is greatly important to know about the reason why men can grow male breast cancer. According to many researchers, besides inherited or genetic aspects, it also can be environmental problems that are possible to contribute in its development.
Recognized gene in the family or family history contributes about 5-10% of all breast cancer in men. In addition, exposure to radiation continually and high levels of estrogen for a long time in young age could contribute as well.
If it is diagnosed at an early stage, men identified with this cancer have a good opportunity for treatment. However, the symptoms should not be overlooked. The most common symptom of male breast cancer is a breast lump. For the most part of cases are made a diagnosis after the illness has got an advanced condition.
A number of the symptoms are as followed: a lump that is painless in nature; the skin covering the breast feels dimpling, redness, puckering, or scaling; discharge from the nipple; thickening of the breast tissue; and nipple may turn inward.
Male Breast Cancer Treatments:
Actually there are a number of measures that can be used for the treatments, and certain process used may rely on the stage or type of the cancer. Removing the breast with surgical method or mastectomy, then chemotherapy and radiation are methods of breast cancer treatment. However, the male breast cancer treatments must be discussed personally between the patient and doctor.

Courtesy: http://1st-in-breastcancer.com

Association Found Between Stress and Breast Cancer Aggressiveness

We found that after diagnosis, black and Hispanic breast cancer patients reported higher levels of stress than whites, and that stress was associated with tumor aggressiveness," said Garth H. Rauscher, Ph.D., associate professor of epidemiology in the division of epidemiology and biostatistics at the School of Public Health, University of Illinois at Chicago.
Rauscher and colleagues studied patient-reported perceptions of fear, anxiety and isolation, together referred to as psychosocial stress, and associations with breast cancer aggressiveness. He cautioned that patients' stress levels were examined two to three months post-diagnosis.
The study included 989 breast cancer patients who were recently diagnosed; of those, 411 were non-Hispanic black, 397 were non-Hispanic white, and 181 were Hispanic. Results showed that psychosocial stress scores were higher for both black and Hispanic patients compared to white patients.
"Those who reported higher levels of stress tended to have more aggressive tumors. However, what we don't know is if we had asked them the same question a year or five years before diagnosis, would we have seen the same association between stress and breast cancer aggressiveness?
"It's not clear what's driving this association. It may be that the level of stress in these patients' lives influenced tumor aggressiveness. It may be that being diagnosed with a more aggressive tumor, with a more worrisome diagnosis and more stressful treatments, influenced reports of stress. It may be that both of these are playing a role in the association. We don't know the answer to that question," Rauscher said.

Courtesy: www.sciencedaily.com

Birth Control Pills Affect Memory, Researchers Find

Women who use contraceptives like birth control pills experience memory changes, according to new UC Irvine research. Their ability to remember the gist of an emotional event improves, while women not using the contraceptives better retain details.

"What's most exciting about this study is that it shows the use of hormonal contraception alters memory," UCI graduate researcher Shawn Nielsen said. "There are only a handful of studies examining the cognitive effects of the pill, and more than 100 million women use it worldwide."
She stressed that the medications did not damage memory. "It's a change in the type of information they remember, not a deficit."
The change makes sense, said Nielsen, who works with neurobiologist Larry Cahill, because contraceptives suppress sex hormones such as estrogen and progesterone to prevent pregnancy. Those hormones were previously linked to women's strong "left brain" memory by Cahill's research group.
"This new finding may be surprising to some, but it's a natural outgrowth of the research we've been doing on sex differences for 10 years," Cahill said.
A neurobiologist not involved in the latest work agreed it was a logical and intriguing next step in the examination of memory differences between the sexes. Like any research, she added, it would be important to validate it further.
"Larry Cahill is already well known for his phenomenal research linking sex to memory," said Pauline Maki, professor of psychiatry and psychology at the University of Illinois at Chicago, who specializes in memory and brain functioning. "The fact that women on oral contraceptives remembered different elements of a story tells us that estrogen has an influence on how women remember emotional events."
In the study, groups of women either on the contraceptive or experiencing natural hormonal cycles were shown photographs of a mother, her son, and a car accident. The audio narrative differed; some in each group were told the car had hit a curb, while others were told the car had hit the boy and critically injured him.
One week later, all were given surprise tests about what they recalled. Women using hormonal contraceptives for as little as one month remembered more clearly the main steps in the traumatic event -- that there had been an accident, that the boy had been rushed to the hospital, that doctors worked to save his life and successfully reattached both his feet, for instance.
Women not using them remembered more details, such as a fire hydrant next to the car.
Nielsen and fellow researcher Nicole Ertman agreed the findings could help lead to fuller answers about why women experience post traumatic stress syndrome more frequently than men, and how men remember differently than women. Men typically rely more on right-hemisphere brain activity to encode memory. They retain the gist of things better than details. Women on the pill, who have lower levels of hormones associated with female reproduction, may remember emotional events similarly to men. Nielsen plans to do her doctoral thesis on whether hormones affect the retention of details.
The work, funded by the National Institute of Mental Health, appears in the September issue of the journal Neurobiology of Learning and Memory. Additional authors include Cahill and UCI undergraduate research assistant Yasmeen Lakhani.

Courtesy: www.sciencedaily.com