29th Mar 2014, 12:23 PM #941
Re: Health Bulletin
Its official! Heart responds differently to exercise in men and women
Researchers have said that the formula for peak exercise heart rate that doctors have used for decades to diagnose heart conditions may be flawed as it does not account for differences between men and women.
The simple formula of "220 minus age" has been widely used to calculate the maximum number of heart beats per minute a person can achieve.
Many people use it to derive their target heart rate during a workout. Doctors use it to determine how hard a patient should exercise during a common diagnostic test known as the exercise stress test.
After analyzing more than 25,000 stress tests, the researchers found significant differences between men and women and developed an updated formula to reflect those nuances.
Thomas Allison, M.D., cardiologist and director of stress testing at Mayo Clinic, and senior author of the study, said that the standard that's currently in use is somewhat outdated.
The new formula can help people better optimize their workouts and also improve the accuracy of test results. Stress tests, which are commonly used to help diagnose conditions such as coronary heart disease, heart valve disease and heart failure, require patients to exercise near their top capacity while technicians monitor the patient's cardiac performance.
The researchers drew data from 25,000 patients who took stress tests at Mayo Clinic between 1993 and 2006. The sample included men and women 40 to 89 years of age who had no history of cardiovascular disease.
Women in the age range of 40 to 89 years should expect their maximum heart rate to be 200 minus 67 percent of their age. In men, the formula is 216 minus 93 percent of their age. For women younger than 40, the relationship of heart rate to age may be different, as an insufficient number of tests on women younger than 40 were available to provide reliable results.
29th Mar 2014, 12:24 PM #942
Re: Health Bulletin
3D printed plastic skull successfully implanted in woman
22-year-old woman's was 5cm and caused pressure and sight loss, doctors said
“Implants used to be made by hand in the operating theatre using a sort of cement which was far from ideal,” neurologist Dr Ben Verweij was quoted as telling to the Mirror.
He said by making use of 3D printing they could make one to the exact size, and this not only had great cosmetic advantages, but patients' brain function often recovered better than using the old method.
Dr Verweij added that the patient has her sight back entirely, is symptom-free and has gone back to work, asserting that it was almost impossible to make out if she's ever had surgery.
Although the Dutch operation is considered the world's first full-skull transplant using 3D printing, a similar surgery was conducted on an American man in 2013, in which 75 percent of his skull was replaced with an implant printed by 3D technology.
30th Mar 2014, 12:31 AM #943
Re: Health Bulletin
Anti-aging hormones may have opposite effect
Do you take anti-aging pills or injections in a quest to replenish youthful hormones to immortalise yourself? Get alarmed as these injections of growth hormone may have the opposite effect as intended.
A study reveals that taking growth hormones as an anti-aging strategy may undermine the body's natural defenses against the diseases of old age.
The primary hormones administered are human growth hormone (HGH) which prompts the body to make another hormone called insulin-like growth factor 1 (IGF-1) and dehydroepiandrosterone (DHEA), a precursor of estrogen and testosterone.
The researchers followed 184 men and women in their mid-90s for up to 11 years.
The chance of living through the length of the study depended mostly on the participants' blood levels of IGF-1.
Every 1-nanogram per milliliter decrease in IGF-1 translated into about one more week of life.
The lower IGF-1 levels were particularly beneficial for cancer survivors.
Three years after entering the study, 75 percent of participants who had previously had cancer and also low IGF-1 levels were still living, whereas only about 25 percent of participants with past cancer and higher IGF-1 were alive.
"The risks of using HGH as an anti-aging strategy outweigh the potential benefits," said Sofiya Milman, an assistant professor of endocrinology at Albert Einstein College of Medicine in New York.
The research appeared in the journal Aging Cell.
30th Mar 2014, 12:32 AM #944
Re: Health Bulletin
Underweight people at as high risk of dying as obese people: Study
At a time when the world is concentrating on the obesity epidemic, Canadian researchers have found that people who are underweight have the highest risk of dying. If the risk of dying for obese people (vis a vis normal weight people) is 1.2 times then the risk for the underweight is almost 1.8 times, said the study published in the Journal of Epidemiology and Public Health.
The study, led by Dr Joel Ray of St Michael's Hospital, looked at 51 studies on the links between BMI (bady mass index) and deaths from any cause, plus data on newborn weight and stillbirths in Ontario. He found that adults who are underweight - with a BMI under 18.5 or less - have a 1.8 times higher risk of dying than those with a "normal" BMI of 18.5 to 24.9.
The risk of dying is 1.2 times higher for people who are obese (BMI of 30-34.9) and 1.3 times higher for those who are severely obese (a BMI of 35 or higher).
Common causes for being underweight include malnourishment, heavy alcohol or drug use, smoking, low-income status, mental health or poor self-care. "BMI reflects not only body fat, but also muscle mass. If we want to continue to use BMI in health care and public health initiatives, we must realize that a robust and healthy individual is someone who has a reasonable amount of body fat and also sufficient bone and muscle," Dr Ray said. He feels waist circumference is a better indicator of health than BMI.
Dr Ray also said that as society aims to curb the obesity epidemic, "we have obligation to ensure that we avoid creating an epidemic of underweight adults and fetuses who are otherwise at the correct weight. We are, therefore, obliged to use the right measurement tool."
30th Mar 2014, 12:53 PM #945
Re: Health Bulletin
Does partner love you? Yawn to check
Here's a test to see if your partner loves you. Look at her, and yawn. If she does not yawn back, chances are your relationship might be in trouble. Or so says a University of Pisa, Italy, study which looked at 109 men and women from different countries and studied their yawning patterns. The researchers found yawns are especially contagious when in the company of close family — parents, siblings and children. And should one family member yawn, chances are others will too.
On the other hand, contagious yawning was slightly less common among mere friends, and rarer still among strangers or casual acquaintances.
The study also found that not all contagious yawns were equal. The closer the relationship, the smaller the time difference between the yawns of the "yawner" and the "yawnee".
Therefore, the time difference between yawns could say a lot about the strength of a relationship. Are the two of you best friends forever, or just friends? Intimate lovers, or just friends with benefits?
If the study's results are pinpoint accurate, the takeaway is that the more someone is into you, the shorter their average yawn delay ought to be. So, say the experts somewhat lightheartedly, if you're the kind who really needs to know whether your partner is into you or not, you could begin to start keeping track. And then if you notice a change in the yawn delay over time, that would be your way of telling whether your partner is falling in or out of love with you.
Although of course, say the experts again, you would be wise to remember that tests like these are speculative. And that while the experiment raises some very interesting questions, it might also reveal more about you than your partner. Or, more specifically, how good a partner are you being if you feel the need to test your relationship in this way.
30th Mar 2014, 01:08 PM #946
Re: Health Bulletin
Cholesterol levels vary by season, get worse in colder months
Cholesterol levels fluctuate based on the time of year with more unfavourable lipid profiles seen in the colder months, an Indian-origin scientist has found. The trend may be driven by behavioural changes that occur with the changing seasons, researchers said.
While previous studies have shown that heart attacks and heart-related deaths increase during the winter months, researchers at Johns Hopkins Ciccarone Center for the Prevention of Heart Disease were interested in finding out whether cholesterol parameters might follow a similar pattern. They studied a sample of 2.8 million adults - the largest study to look at seasonal lipid trends in US adults to date.
"In this very large sample, we found that people tend to have worse cholesterol numbers on average during the colder months than in the warmer months - not by a very large amount, but the variation is significant," said Parag Joshi, cardiology fellow, Johns Hopkins Hospital, and lead investigator of the study.
"It confirms findings from smaller studies and raises a lot of interesting questions, including what might be driving these [fluctuations]," Joshi said.
"In the summer, we tend to get outside, we are more active and have healthier behaviours overall," Joshi said.
"In the colder months, we tend to crawl into our caves, eat [fat-laden] comfort foods and get less exercise, so what we see is that LDL and non-HDL [bad cholesterol markers] are slightly worse".
"So you have a lipid signature of higher risk, but it's probably driven by a lot of behaviours that occur with the changing seasons," Joshi added.
Researchers speculate the shorter days of winter - and limited time spent outside - also mean less sun exposure and, subsequently, lower concentrations of vitamin D, which has also been associated with the ratio of bad to good cholesterol.
In the study, researchers analysed lipid profiles in US adults who were referred for testing by their doctors from 2006 to 2013. Samples were categorised by the time of year when cholesterol was measured and comparisons were made across the seasons.
Total cholesterol, low density lipoprotein (LDL) and non-high density lipoprotein (non-HDL) cholesterol levels were all higher in the winter than in the summer. LDL and non-HDL cholesterol were 4 mg/dL higher in men and 2 mg/dL higher in women during the colder vs warmer months - a 3.5 per cent and 1.7 per cent increase, respectively.
Triglycerides were 2.5 per cent higher in men during the winter compared with the summer. Women and men had variations in total cholesterol of approximately 2 mg/dL and 4 mg/dL, respectively, between the summer to winter, researchers found.
31st Mar 2014, 12:01 PM #947
Re: Health Bulletin
Are statins good for your love life?
Statins, the popular cholesterol-lowering drugs, may offer added benefit for men with erectile dysfunction, says a new research from Rutgers Robert Wood Johnson Medical School.
Erectile dysfunction affects an estimated 18 million to 30 million men and occurs more often in men over the age of 40. Common causes include heart disease, high cholesterol, high blood pressure, diabetes, obesity, tobacco use, depression and stress.
A team of doctors led by John B Kostis conducted the first meta-analysis of previous studies on erectile dysfunction and statins. They analysed 11 trials to find a significant effect of statins on erectile function in men who had both high cholesterol and erectile dysfunction. Their erectile function scores increased by 3.4 points (from 14.0 to 17.4).
"The increase in erectile function scores with statins was approximately one-third to one-half of what has been reported with drugs like Viagra, Cialis or Levitra," said Kostis.
Statins most possibly work in the same manner as Viagra does: they improve erectile function by helping blood vessels dilate properly and improving vascular blood flow to the penis (which is restricted in men with erectile dysfunction).
The doctors, however, said statins are not recommended as a primary treatment for erectile dysfunction in patients with healthy cholesterol levels.
1st Apr 2014, 01:23 AM #948
Re: Health Bulletin
On the anvil, a gel to 'fix' implants
In the near future, surgeons may only need to apply a gel to the implant they are placing to ensure that the body doesn't reject it.
A research group at Uppsala University, Sweden has developed a new responsive coating for implants used in surgery to improve their integration into bone and to prevent rejection.
Orthopaedic and dental implants must last for many years. Success for these surgical components depends on integration into adjacent bone tissue. Gels made by modifying hyaluronan, a large biological molecule, can be used to coat implants,'' said a press release put online by the university.
The university's research paper in Advanced Engineering Materials shows that the coated titanium surfaces can bind protein molecules which promote bone formation. These can be released slowly once the surface comes in contact with a solution of calcium ions. This process would stimulate the growth of bone on the implant,'' it added.
The research group has now launched trials of similar materials for metal implants in rabbits. These ongoing studies are made in collaboration with the Swedish Agricultural University in Uppsala and they provide a step towards transfer of the results to clinical applications.
1st Apr 2014, 06:31 PM #949
Re: Health Bulletin
Happily disgusted? Your face will show it: Study
Faces are windows to the soul, it is said. Whatever your emotion, the face has a typical expression for it — and this is common to all humanity. Up till now, only six emotions were clearly identifiable through facial expressions. They were — happy, sad, fearful, angry, surprised and disgusted.
Now, researchers at the Ohio State University have found a way for computers to recognize 21 distinct facial expressions—even expressions for complex or seemingly contradictory emotions such as "happily disgusted" or "sadly angry." The research is published in the current issue of the Proceedings of the National Academy of Sciences.
"We've gone beyond facial expressions for simple emotions like 'happy' or 'sad.' We found a strong consistency in how people move their facial muscles to express 21 categories of emotions," said Aleix Martinez, a cognitive scientist and associate professor of electrical and computer engineering at Ohio State. "That is simply stunning. That tells us that these 21 emotions are expressed in the same way by nearly everyone, at least in our culture."
"Happily disgusted," for instance, creates an expression that combines the scrunched-up eyes and nose of "disgusted" with the smile of "happy." "Happily surprised" turned out to be a compound of the expressions for "happy" and "surprised." About 93% of the time, the participants expressed it the same way: with the wide-open eyes of surprise and the raised cheeks of happiness—and a mouth that was a hybrid of the two—both open and stretched into a smile.
The resulting computational model will help map emotion in the brain with greater precision than ever before, and perhaps even aid the diagnosis and treatment of mental conditions such as autism and post-traumatic stress disorder (PTSD). Cognitive scientists want to link facial expressions to emotions in order to track the genes, chemicals, and neural pathways that govern emotion in the brain.
Until now, cognitive scientists have confined their studies to six basic emotions mostly because the facial expressions for them were thought to be self-evident, Martinez explained. But deciphering a person's brain functioning with only six categories is like painting a portrait with only primary colors, Martinez said: it can provide an abstracted image of the person, but not a true-to-life one.
The Ohio University scientists photographed 230 volunteers—130 female, 100 male, and mostly college students—making faces in response to verbal cues such as "you just got some great unexpected news" ("happily surprised"), or "you smell a bad odor" ("disgusted"). In the resulting 5,000 images, they painstakingly tagged prominent landmarks for facial muscles, such as the corners of the mouth or the outer edge of the eyebrow. They used the same method used by psychologist Paul Ekman, the scientific consultant for the television show "Lie to Me." Ekman's Facial Action Coding System, or FACS, is a standard tool in body language analysis.
1st Apr 2014, 06:35 PM #950
Re: Health Bulletin
Scientists develop test to identify date rape drug in 30 seconds
Scientists have successfully developed the world's first fluorescent sensor to identify the presence of GHB — commonly called the date rape drug.
Gamma-Hydroxybutyric acid (GHB) is a central nervous system depressant that has been used medically as a general anaesthetic.
In the 1990s, it gained notoriety as a drug allegedly used in instances of drink spiking. Today, it is one of the most commonly used date rape drugs, rendering the victim incapacitated and vulnerable to sexual assault.
Researchers from the National University of Singapore (NUS) have now developed the world's first fluorescent sensor to detect GHB. When the sensor is mixed with a sample of a beverage containing GHB, the mixture changes colour in less than 30 seconds, making detection of the drug fast and easy.
This simple mix-and-see discovery, led by Professor Chang Young-Tae of the Department of Chemistry at the NUS Faculty of Science, is a novel scientific breakthrough that contributes towards prevention of drug-facilitated sexual assault problems.
As GHB is odourless, colourless and slightly salty, it is almost undetectable when mixed in a drink, thus making it desirable to sexual predators. A small amount of between two to four grams of GHB will interfere with the motor and speech control of a person, and may even induce a coma-like sleep.
GHB takes effect within 15 to 30 minutes, and the effect can last for three to six hours. It is only detectable in urine six to 12 hours after ingestion.
Fluorescent dyes have been widely used as sensors for analytical purposes because of their high sensitivity, fast response time and technical simplicity.
Under the supervision of Prof Chang, the team of researchers screened 5,500 dyes generated from different fluorescent scaffolds. These fluorescent scaffolds have been used to construct the Diversity Oriented Fluorescence Library (DOFL) that was developed by Prof Chang over the last decade.
The team shortlisted 17 fluorescent compounds and further tested them with a wide range of different GHB concentrations. Through this, the team identified that an orange fluorescent compound, coined GHB Orange, changes colour when it is mixed with GHB.
Remarkably, this detection can be done through a simple mix-and-see process, which takes less than 30 seconds.
While GHB Orange has proven to be efficient in detecting GHB in beverages, there is a need to develop a test kit that is convenient for users to use and carry around. Prof Chang and his team intend to work with industry partners to develop a handy and cheap device for GHB detection.