sexta-feira, 17 de abril de 2015

Facebook users' wishful thinking: Cyberbullying, depression won't happen to me

April 16, 2015

Dartmouth College

Facebook users with so-called optimistic bias think they're less likely than other users to experience cyberbullying, depression and other negative social and psychological effects from using the site, a study finds. The study suggests that optimistic bias, or an intrinsic tendency to imagine future events in a favorable light that enhances positive self-regard -- in other words, wishful thinking -- leaves those Facebook users vulnerable to the negative realities of social media.


Facebook users with so-called optimistic bias think they're less likely than other users to experience cyberbullying, depression and other negative social and psychological effects from using the site, a Dartmouth-Cornell study finds.

The study suggests that optimistic bias, or an intrinsic tendency to imagine future events in a favorable light that enhances positive self-regard -- in other words, wishful thinking -- leaves those Facebook users vulnerable to the negative realities of social media.

The findings appear in the journal Cyberpsychology, Behavior, and Social Networking.

"Our findings demonstrate important and novel discrepancies in how people perceive themselves and others concerning the positive and negative outcomes of Facebook use," says lead author Sunny Jung Kim, a postdoctoral research associate in the Psychiatric Research Center and the Center for Technology and Behavioral Health at the Geisel School of Medicine at Dartmouth. "A growing number of studies report possible benefits and risks of using Facebook and other social media, ranging from effects on self-esteem to cyberbullying. But little is known about how people perceive themselves to be likely to experience these mixed outcomes and what the implications of having these perceptions are."

In the new study, the researchers surveyed 237 active Facebook users between ages 18 and 37. The participants were asked to assess their own and other people's likelihood of experiencing positive and negative outcomes on Facebook. They also were asked to rate their likelihood of supporting Internet regulations, their personal Facebook involvement and their attitudes toward Facebook use. The results show that Facebook users with optimistic bias tend to show strong support for Internet regulations to protect other users from social ostracizing, although not from psychologically negative effects, including depression and loneliness. The lack of support regarding psychological harms may be because mental health effects are perceived as less amenable to regulation or because their importance is underestimated, the researchers say.

The results also show that Facebook users who view the site negatively or who use it infrequently think other people are more likely than themselves to have positive experiences on the site, a reversed optimistic bias that is new and intriguing. "When ostensibly positive outcomes, such as receiving social support from Facebook friends, are perceived to be unusual and irrelevant for themselves, the direction of the optimistic bias for these objectively positive outcomes can be dampened or even reversed," Kim says. Co-author Cornell Professor Jeffrey Hancock adds: "It's fascinating that well-established, third-person effects are also seen on Facebook, but the reversal shows how social media is not identical to mass media."

"Although some might argue that it is still premature to claim that Facebook use is a direct predictor of extreme events such as clinical depression and suicidal attempts, a growing line of research indicates that negative events such as Facebook cyberbullying can result in detrimental consequences, including depression and substance use problems," Kim says. "Without adequate protections, the damage of these critical events can be severe. This is especially the case for those in a vulnerable health condition, in which this optimistic bias for risk events can leave them unprepared without adequate health protective behaviors. We argue that Facebook may serve as a source of emotional support between users and as a platform to disseminate protective health messages to prevent negative psychological consequences of Facebook use. Given that negative personal and health news such as stressful events and depressive symptoms are frequently shared on Facebook, it may be an important site for observing negative psychological states of users."


Story Source:

The above story is based on materials provided by Dartmouth College. Note: Materials may be edited for content and length.


Journal Reference:

  1. Sunny Jung Kim, Jeffrey T. Hancock. Optimistic Bias and Facebook Use: Self–Other Discrepancies About Potential Risks and Benefits of Facebook Use. Cyberpsychology, Behavior, and Social Networking, 2015; 18 (4): 214 DOI: 10.1089/cyber.2014.0656

 

quinta-feira, 16 de abril de 2015

É mentira, Terta?

A Felicidade

Eight nutrients to protect the aging brain

 

Brain health is the second most important component in maintaining a healthy lifestyle according to a 2014 AARP study. As people age they can experience a range of cognitive issues from decreased critical thinking to dementia and Alzheimer's disease. In the March issue of Food Technology published by the Institute of Food Technologists (IFT), contributing editor Linda Milo Ohr writes about eight nutrients that may help keep your brain in good shape.

1. Cocoa Flavanols: Cocoa flavanols have been linked to improved circulation and heart health, and preliminary research shows a possible connection to memory improvement as well. A study showed cocoa flavanols may improve the function of a specific part of the brain called the dentate gyrus, which is associated with age-related memory (Brickman, 2014).

2. Omega-3 Fatty Acids: Omega-3 fatty acids have long been shown to contribute to good heart health are now playing a role in cognitive health as well. A study on mice found that omega-3 polyunsaturated fatty acid supplementation appeared to result in better object recognition memory, spatial and localizatory memory (memories that can be consciously recalled such as facts and knowledge), and adverse response retention (Cutuli, 2014). Foods rich in omega-3s include salmon, flaxseed oil, and chia seeds.

3. Phosphatidylserine and Phosphatidic Acid: Two pilot studies showed that a combination of phosphatidylserine and phosphatidic acid can help benefit memory, mood, and cognitive function in the elderly (Lonza, 2014).

4. Walnuts: A diet supplemented with walnuts may have a beneficial effect in reducing the risk, delaying the onset, or slowing the progression of Alzheimer's disease in mice (Muthaiyah, 2014).

5. Citicoline: Citicoline is a natural substance found in the body's cells and helps in the development of brain tissue, which helps regulate memory and cognitive function, enhances communication between neurons, and protects neural structures from free radical damage. Clinical trials have shown citicoline supplements may help maintain normal cognitive function with aging and protect the brain from free radical damage. (Kyowa Hakko USA).

6. Choline: Choline, which is associated with liver health and women's health, also helps with the communication systems for cells within the brain and the rest of the body. Choline may also support the brain during aging and help prevent changes in brain chemistry that result in cognitive decline and failure. A major source of choline in the diet are eggs.

7. Magnesium: Magnesium supplements are often recommended for those who experienced serious concussions. Magnesium-rich foods include avocado, soy beans, bananas and dark chocolate.

8. Blueberries: Blueberries are known to have antioxidant and anti-inflammatory activity because they boast a high concentration of anthocyanins, a flavonoid that enhances the health-promoting quality of foods. Moderate blueberry consumption could offer neurocognitive benefits such as increased neural signaling in the brain centers.


Story Source:

The above story is based on materials provided by Institute of Food Technologists (IFT). Note: Materials may be edited for content and length.


 

Alcohol use: If you drink, keep it moderate

 

 

Resultado de imagem para Imagens de alcool com moderação

Alcohol use can be a slippery slope. Moderate drinking can offer some health benefits. But heavy drinking can have serious consequences.

By Mayo Clinic Staff

It sounds like a mixed message: Drinking alcohol may offer some health benefits, especially for your heart. On the other hand, alcohol may increase your risk of health problems and damage your heart.

So which is it? When it comes to drinking alcohol, the key is doing so only in moderation. Certainly, you don't have to drink any alcohol, and if you currently don't drink, don't start drinking for the possible health benefits. In some cases, it's safest to avoid alcohol entirely — the possible benefits don't outweigh the risks.

Here's a closer look at the connection between alcohol and your health.

Health benefits of moderate alcohol use

Moderate alcohol consumption may provide some health benefits. It may:

  • Reduce your risk of developing and dying from heart disease
  • Possibly reduce your risk of ischemic stroke (when the arteries to your brain become narrowed or blocked, causing severely reduced blood flow)
  • Possibly reduce your risk of diabetes

Even so, the evidence about the possible health benefits of alcohol isn't certain, and alcohol may not benefit everyone who drinks.

Guidelines for moderate alcohol use

If you choose to drink alcohol, do so only in moderation. For healthy adults, that means up to one drink a day for women of all ages and men older than age 65, and up to two drinks a day for men age 65 and younger.

Examples of one drink include:

  • Beer: 12 fluid ounces (355 milliliters)
  • Wine: 5 fluid ounces (148 milliliters)
  • Distilled spirits (80 proof): 1.5 fluid ounces (44 milliliters)

Moderate alcohol use may be of most benefit if you're an older adult or if you have existing risk factors for heart disease. If you're a middle-aged or younger adult, some evidence shows that even moderate alcohol use may cause more harm than good. You can take other steps to benefit your cardiovascular health besides drinking — eating a healthy diet and exercising, for example.

When to avoid alcohol use

In certain situations, the risks of alcohol use may outweigh the possible health benefits. For example, use alcohol only with great care and after consulting your doctor if:

  • You're pregnant or trying to become pregnant
  • You've been diagnosed with alcoholism or alcohol abuse, or you have a strong family history of alcoholism
  • You have liver or pancreatic disease
  • You have heart failure or you've been told you have a weak heart
  • You take prescription or over-the-counter medications that can interact with alcohol
  • You've had a hemorrhagic stroke (when a blood vessel in your brain leaks or ruptures)

Keep in mind that even moderate use isn't risk-free. For example, drinking and driving is never a good idea.

The risks of heavy alcohol use

Heavy drinking is defined as more than three drinks on any day or more than seven drinks a week for women and for men older than age 65, and more than four drinks on any day or more than 14 drinks a week for men age 65 and younger. Binge drinking is defined as four or more drinks within two hours for women and five or more drinks within two hours for men.

While moderate alcohol use may offer some health benefits, heavy drinking — including binge drinking — has no health benefits. Excessive drinking can increase your risk of serious health problems, including:

  • Certain cancers, including breast cancer and cancers of the mouth, pharynx, larynx and esophagus
  • Pancreatitis
  • Sudden death if you already have cardiovascular disease
  • Heart muscle damage (alcoholic cardiomyopathy) leading to heart failure
  • Stroke
  • High blood pressure
  • Liver disease
  • Suicide
  • Accidental serious injury or death
  • Brain damage and other problems in an unborn child
  • Alcohol withdrawal syndrome
Drink alcohol only in moderation — or not at all

The latest dietary guidelines make it clear that no one should begin drinking or drink more frequently on the basis of potential health benefits. So don't feel pressured to drink alcohol. But if you do drink alcohol and you're healthy, there's probably no need to stop as long as you drink responsibly and in moderation.

Video games can power up from merely fun to meaningful experiences

 

 

It may be game over for critics who claim that video games are nothing more than a fun diversion. A team of researchers suggests that many games can be meaningful entertainment experiences for players.

In a study of people's experiences with video games, players indicated that they not only enjoyed playing games, but that they also frequently appreciated them at a deeper, more meaningful level. These findings should be encouraging to video game developers who want to invest in producing games that examine more meaningful, poignant or contemplative topics.

"Video games are often stereotyped as something that is just fun and entertaining, but not something that is deeply appreciated," said Mary Beth Oliver, Distinguished Professor in Media Studies and co-director of Media Effects Research Laboratory, Penn State. "Video games do not seem to have the same critical acclaim as, for example, books and plays or even music."

Participants in the study suggested that story details in the game were critical to feelings of appreciation. They also indicated that more meaningful games were associated with heightened feelings of insight or enrichment.

"That insight could be anything from an emotion or virtue -- like courage -- to an insight on human spirituality," said Oliver.

The researchers, who report their findings in the current issue of Psychology of Popular Media Culture, said games may hold promise of providing players with enriching or gratifying experiences.

"It's certainly true that there are some games that are silly or shallow, but that's the case for almost all forms of entertainment," said Oliver. "Our research suggests that contrary to stereotypes, games have the potential to be as meaningful to players as other, more esteemed forms of entertainment such as literature or cinema."

Games may also provide players the opportunity to experience valuable situations and emotions that other forms of entertainment may not do as frequently, Oliver added.

"Whereas viewers and readers typically watch characters make decisions in movies and books, many video games allow the player to actually make those choices, resulting in feelings such as guilt or pride," she added.

Creating games with more interactive and more meaningful story lines is a challenge for developers, but could be worth the investment, the researchers indicate.

The increased focus on narrative and emotions is a natural evolution in video games, said Nick Bowman, assistant professor of communication studies and a research associate, West Virginia University, who worked with Oliver.

"The earliest video games really had very little in common with other forms of narrative entertainment," said Bowman. "Games have grown from simple point-and-click twitch games to incredibly engrossing emotional experiences and games now have the potential to give us the same sorts of feelings that great novels and music do."

For example, Bowman said at one point in the game Spec Ops, the player is faced with the moral decision to use chemical weapons on an enemy. One consequence of choosing to do so is that innocent refugees are victims of the attack. The player is forced to witness the results of his or her actions, triggering a mix of emotions.

"Such an experience gives players a space to challenge how they see the world, just as movies like Schindler's List or novels like Animal Farm, did for past audiences," said Bowman. "Video games have grown up."

In the study, 512 video game players were assigned to one of two random groups and asked to recall games that were particularly fun or particularly meaningful. They then rated their perceptions about the game. While participants reported that they found both types were fun to play, they said they had more appreciation for the more meaningful games they played.

Teachers more likely to label black students as troublemakers

 

Teachers are likely to interpret students' misbehavior differently depending on the student's race, according to new research findings published in Psychological Science, a journal of the Association for Psychological Science.

Racial differences in school discipline are widely known, and black students across the United States are more than three times as likely as their white peers to be suspended or expelled, according to Stanford researchers.

Yet the psychological processes that contribute to those differences have not been clear -- until now.

"The fact that black children are disproportionately disciplined in school is beyond dispute," said Stanford psychology Professor Jennifer Eberhardt in an interview. "What is less clear is why."

Eberhardt and Stanford psychology graduate student Jason Okonofua examined the psychological processes involved when teachers discipline black students more harshly than white students.

In the studies, real-world primary and secondary school teachers were presented with school records describing two instances of misbehavior by a student. In one study, after reading about each infraction, the teachers were asked about their perception of its severity, about how irritated they would feel by the student's misbehavior, about how severely the student should be punished, and about whether they viewed the student as a troublemaker.

A second study followed the same protocol and asked teachers whether they thought the misbehavior was part of a pattern and whether they could imagine themselves suspending the student in the future.

The researchers randomly assigned names to the files, suggesting in some cases that the student was black (with a name such as DeShawn or Darnell) and in other cases that the student was white (with a name such as Greg or Jake).

Across both studies, the researchers found that racial stereotypes shaped teachers' responses not after the first infraction but rather after the second. Teachers felt more troubled by a second infraction they believed was committed by a black student rather than by a white student.

In fact, the stereotype of black students as "troublemakers" led teachers to want to discipline black students more harshly than white students after two infractions, Eberhardt and Okonofua said. They were more likely to see the misbehavior as part of a pattern, and to imagine themselves suspending that student in the future.

"We see that stereotypes not only can be used to allow people to interpret a specific behavior in isolation, but also stereotypes can heighten our sensitivity to behavioral patterns across time. This pattern sensitivity is especially relevant in the schooling context," Eberhardt said.

These results have implications beyond the school setting as well.

As Okonofua said, "Most social relationships entail repeated encounters. Interactions between police officers and civilians, between employers and employees, between prison guards and prisoners all may be subject to the sort of stereotype escalation effect we have identified in our research."

Both Okonofua and Eberhardt suggested that useful interventions with teachers would help them to view student behavior as malleable rather than as a reflection of a fixed disposition, such as that of troublemaker.

While racial disparities can be lessened by psychological interventions that help improve black students' behaviors in class, it is also important to understand how that behavior is interpreted by teachers and school authorities, Okonofua said.

New potential cause for Alzheimer's: Arginine deprivation caused by overconsumption by immune cells

 

A new Duke University study in mice suggests that in Alzheimer's disease, certain immune cells that normally protect the brain begin to abnormally consume an important nutrient: arginine. Blocking this process with a small-molecule drug prevented the characteristic brain plaques and memory loss in a mouse model of the disease.

Published April 15 in the Journal of Neuroscience, the new research not only points to a new potential cause of Alzheimer's but also may eventually lead to a new treatment strategy.

"If indeed arginine consumption is so important to the disease process, maybe we could block it and reverse the disease," said senior author Carol Colton, professor of neurology at the Duke University School of Medicine, and a member of the Duke Institute for Brain Sciences.

The brains of people with Alzheimer's disease show two hallmarks -- 'plaques' and 'tangles' -- that researchers have puzzled over for some time. Plaques are the build up of sticky proteins called beta amyloid, and tangles are twisted strands of a protein called tau.

In the study, the scientists used a type of mouse, called CVN-AD, that they had created several years ago by swapping out a handful of important genes to make the animal's immune system more similar to a human's.

Compared with other mice used in Alzheimer's research, the CVN-AD mouse has it all: plaques and tangles, behavior changes, and neuron loss.

In addition, the gradual onset of these symptoms in the CVN-AD mouse gave researchers a chance to study its brain over time and to focus on how the disease begins, said the study's first author Matthew Kan, an MD/PhD student in Colton's lab.

Looking for immune abnormalities throughout the lifespan of the mice, the group found that most immune system components stayed the same in number, but a type of brain-resident immune cells called microglia that are known first responders to infection begin to divide and change early in the disease.

The microglia express a molecule, CD11c, on their surface. Isolating these cells and analyzing their patterns of gene activity, the scientists found heightened expression of genes associated with suppression of the immune system. They also found dampened expression of genes that work to ramp up the immune system.

"It's surprising, because [suppression of the immune system is] not what the field has been thinking is happening in AD," Kan said. Instead, scientists have previously assumed that the brain releases molecules involved in ramping up the immune system, that supposedly damage the brain.

The group did find CD11c microglia and arginase, an enzyme that breaks down arginine, are highly expressed in regions of the brain involved in memory, in the same regions where neurons had died.

Blocking arginase using the small drug difluoromethylornithine (DFMO) before the start of symptoms in the mice, the scientists saw fewer CD11c microglia and plaques develop in their brains. These mice performed better on memory tests.

"All of this suggests to us that if you can block this local process of amino acid deprivation, then you can protect -- the mouse, at least -- from Alzheimer's disease," Kan said.

DFMO is being investigated in human clinical trials to treat some types of cancer, but it hasn't been tested as a potential therapy for Alzheimer's. In the new study, Colton's group administered it before the onset of symptoms; now they are investigating whether DFMO can treat features of Alzheimer's after they appear.

Does the study suggest that people should eat more arginine or take dietary supplements? The answer is 'no,' Colton said, partly because a dense mesh of cells and blood vessels called the blood-brain barrier determines how much arginine will enter the brain. Eating more arginine may not help more get into the sites of the brain that need it. Besides, if the scientists' theory is correct, then the enzyme arginase, unless it's blocked, would still break down the arginine.

"We see this study opening the doors to thinking about Alzheimer's in a completely different way, to break the stalemate of ideas in AD," Colton said. "The field has been driven by amyloid for the past 15, 20 years and we have to look at other things because we still do not understand the mechanism of disease or how to develop effective therapeutics."

quarta-feira, 15 de abril de 2015

A camera that powers itself

Wed, 04/15/2015 - 10:03am

Holy Evarts, Columbia Univ. School of Engineering and Applied Science

A video camera based on a self-powered image sensor can run indefinitely without an external power supply. Image: Computer Vision Laboratory, Columbia Engineering

A video camera based on a self-powered image sensor can run indefinitely without an external power supply. Image: Computer Vision Laboratory, Columbia EngineeringA research team led by Shree K. Nayar, T.C. Chang Professor of Computer Science at Columbia Engineering, has invented a prototype video camera that is the first to be fully self-powered—it can produce an image each second, indefinitely, of a well-lit indoor scene. They designed a pixel that can not only measure incident light but also convert the incident light into electric power.

"We are in the middle of a digital imaging revolution," says Nayar, who directs the Computer Vision Laboratory at Columbia Engineering. He notes that in the last year alone, approximately two billion cameras of various types were sold worldwide. "I think we have just seen the tip of the iceberg. Digital imaging is expected to enable many emerging fields including wearable devices, sensor networks, smart environments, personalized medicine, and the Internet of Things. A camera that can function as an untethered device forever—without any external power supply—would be incredibly useful."

A leading researcher in computational imaging, Nayar realized that although digital cameras and solar panels have different purposes—one measures light while the other converts light to power—both are constructed from essentially the same components. At the heart of any digital camera is an image sensor, a chip with millions of pixels. The key enabling device in a pixel is the photodiode, which produces an electric current when exposed to light. This mechanism enables each pixel to measure the intensity of light falling on it. The same photodiode is also used in solar panels to convert incident light to electric power. The photodiode in a camera pixel is used in the photoconductive mode, while in a solar cell it is used in the photovoltaic model.

Nayar, working with research engineer Daniel Sims BS'14 and consultant Mikhail Fridberg of ADSP Consulting, used off-the-shelf components to fabricate an image sensor with 30x40 pixels. In his prototype camera, which is housed in a 3D-printed body, each pixel's photodiode is always operated in the photovoltaic mode.

The pixel design is very simple, and uses just two transistors. During each image capture cycle, the pixels are used first to record and read out the image and then to harvest energy and charge the sensor's power supply—the image sensor continuously toggles between image capture and power harvesting modes. When the camera is not used to capture images, it can be used to generate power for other devices, such as a phone or a watch.

Nayar notes that the image sensor could use a rechargeable battery and charge it via its harvesting capability: "But we took an extreme approach to demonstrate that the sensor is indeed truly self-powered and used just a capacitor to store the harvested energy."

"A few different designs for image sensors that can harvest energy have been proposed in the past. However, our prototype is the first demonstration of a fully self-powered video camera," he continues. "And, even though we've used off-the-shelf components to demonstrate our design, our sensor architecture easily lends itself to a compact solid-state imaging chip. We believe our results are a significant step forward in developing an entirely new generation of cameras that can function for a very long duration—ideally, forever—without being externally powered."

Source: Columbia Univ.

Statins: Are these cholesterol-lowering drugs right for you?

Find out whether your risk factors for heart disease make you a good candidate for statin therapy.

By Mayo Clinic Staff

Statins are drugs that can lower your cholesterol. They work by blocking a substance your body needs to make cholesterol. Statins may also help your body reabsorb cholesterol that has built up in plaques on your artery walls, preventing further blockage in your blood vessels and heart attacks.

Statins include medications such as atorvastatin (Lipitor), fluvastatin (Lescol), lovastatin (Altoprev), pitavastatin (Livalo), pravastatin (Pravachol), rosuvastatin (Crestor) and simvastatin (Zocor). Lower-cost generic versions of many statin medications are available.

Already shown to be effective in lowering cholesterol, statins may have other potential benefits. But doctors are far from knowing everything about statins. Are they right for everybody with high cholesterol? What kinds of side effects may occur? Can statins help prevent other diseases?

Should you be on a statin?

Whether you need to be on a statin depends on your cholesterol level, along with your other risk factors for cardiovascular disease.

Most people should try to keep their total cholesterol level below 200 milligrams per deciliter (mg/dL) (6.22 millimoles per liter, or mmol/L). Low-density lipoprotein cholesterol (LDL, or "bad" cholesterol) should be below 100 mg/dL (3.37 mmol/L).

But the numbers alone won't tell you or your doctor the whole story. High cholesterol is only one of a number of risk factors for heart attack and stroke.

The most important factor to consider is a person's long-term risk of experiencing a heart attack or stroke. If the risk is very low, there is probably no need for statins, unless the LDL is above 190 mg/dL (4.9 mmol/L). If the risk is very high — for example, someone who has had a heart attack in the past — the person may benefit from statins, even if his or her cholesterol is not elevated.

Risk assessment tools

Your doctor may suggest using an online tool to better understand your long-term risks of developing heart disease.

The American College of Cardiology and the American Heart Association have recently developed an online tool to predict a person's chances of having a heart attack in the next 10 years. For people under the age of 50, the Framingham cardiovascular disease risk calculator might be a better option because it provides a 30-year risk prediction.

In addition to your cholesterol numbers, these risk calculators also ask about your age, race, sex, blood pressure and whether you have diabetes or smoke cigarettes.

New cholesterol guidelines

New guidelines from the American College of Cardiology and American Heart Association focus on four main groups of people who may be helped by statins:

  • People who already have cardiovascular disease. This group includes people who have had heart attacks, strokes caused by blockages in a blood vessel, mini-strokes (transient ischemic attacks), peripheral artery disease, or prior surgery to open or replace coronary arteries.
  • People who have very high LDL (bad) cholesterol. This group includes adults who have LDL cholesterol levels of 190 mg/dL (4.9 mmol/L) or higher.
  • People who have diabetes. This group includes adults who have diabetes and an LDL between 70 and 189 mg/dL (1.8 and 4.9 mmol/L), especially if they have evidence of vascular disease.
  • People who have a higher 10-year risk of heart attack. This group includes people who have an LDL above 100 mg/dL (1.8 mmol/L) and whose 10-year risk of a heart attack is 7.5 percent or higher.
Lifestyle is still key for preventing heart disease

Lifestyle changes are essential for reducing your risk of heart disease, whether you take a statin or not. To reduce your risk:

  • Quit smoking and avoid secondhand smoke
  • Eat a healthy diet that's low in saturated fat, trans fat, refined carbohydrates and salt, and rich in fruits, vegetables, fish, and whole grains.
  • Be physically active, sit less and exercise regularly
  • Maintain a healthy waist girth: less than 40 inches in men and less than 35 inches in women

If you're following the recommended lifestyle behaviors but your cholesterol — particularly your LDL (bad) cholesterol — remains high, statins might be an option for you. Risk factors for heart disease and stroke are:

  • Smoking
  • High cholesterol
  • High blood pressure
  • Diabetes
  • Being overweight or obese
  • Family history of heart disease, especially if it was before the age of 55 in male relatives or before 65 in female relatives
  • Not exercising
  • Poor stress and anger management
  • Older age
  • Narrowing of the arteries in your neck, arms or legs (peripheral artery disease)

See more In-depth

Consider statins a lifelong commitment

You may think that once your cholesterol goes down, you can stop taking medication. But if your cholesterol levels have decreased after you take a statin, you'll likely need to stay on it indefinitely. If you stop taking it, your cholesterol levels will probably go back up.

The exception may be if you make significant changes to your diet or lose a lot of weight. Substantial lifestyle changes may help you lower your cholesterol without continuing to take the medication, but don't make any changes to your medications without talking to your doctor first.

The side effects of statins

Although statins are well-tolerated by most people, they do have side effects, some of which may go away as your body adjusts to the medication.

Common, less serious side effects
  • Muscle and joint aches (most common)
  • Headache
  • Nausea
Rare but potentially serious side effects
  • Muscle problems. Statins may cause muscle pain and tenderness, particularly if you're taking a high dosage. In severe cases, muscle cells can break down (rhabdomyolysis) and release a protein called myoglobin into the bloodstream. Myoglobin can damage your kidneys.
  • Liver damage. Occasionally, statin use causes an increase in liver enzymes. If the increase is only mild, you can continue to take the drug. Contact your doctor immediately if you have unusual fatigue or weakness, loss of appetite, pain in your upper abdomen, dark-colored urine, or yellowing of your skin or eyes.
  • Increased blood sugar or type 2 diabetes. It's possible your blood sugar (blood glucose) level may increase when you take a statin, which may lead to developing type 2 diabetes.
  • Cognitive problems. Some people have experienced memory loss and confusion after using statins. However, scientific studies have failed to prove that statins actually cause cognitive problems.

It's important to consider the effects of statins on other organs in your body, especially if you have health problems such as liver or kidney disease. Also, check whether statins interact with any other prescription or over-the-counter drugs or supplements you take.

Keep in mind that when you begin to take a statin, you'll most likely be on it for the rest of your life. Side effects are often minor, but if you experience them, you may want to talk to your doctor about decreasing your dose or trying a different statin. Don't stop taking a statin without talking to your doctor first.

What other benefits do statins have?

Statins may have benefits other than just lowering your cholesterol. One promising benefit of statins appears to be their anti-inflammatory properties, which help stabilize the lining of blood vessels. This has potentially far-reaching effects, from the brain and heart to blood vessels and organs throughout the body.

In the heart, stabilizing the blood vessel linings would make plaques less likely to rupture, thereby reducing the chance of a heart attack. Statins also help relax blood vessels, lowering blood pressure.

Weighing the risks and benefits of statins

When thinking about whether you should take statins for high cholesterol, ask yourself these questions:

  • Do I have other risk factors for cardiovascular disease?
  • Am I willing and able to make lifestyle changes to improve my health?
  • Am I concerned about taking a pill every day, perhaps for the rest of my life?
  • Am I concerned about statins' side effects or interactions with other drugs?

It's important to take into account not only your medical reasons for a decision, but also your personal values and concerns. Talk to your doctor about your total risk of cardiovascular disease and discuss how your lifestyle and preferences play a role in your decision about taking medication for high cholesterol.

 

terça-feira, 14 de abril de 2015

Recruiting the entire immune system to attack cancer

Tue, 04/14/2015 - 11:30am

Anne Trafton, MIT News Office

The human immune system is poised to spring into action at the first sign of a foreign invader, but it often fails to eliminate tumors that arise from the body’s own cells. Cancer biologists hope to harness that untapped power using an approach known as cancer immunotherapy.

Orchestrating a successful immune attack against tumors has proven difficult so far, but a new study from Massachusetts Institute of Technology (MIT) suggests that such therapies could be improved by simultaneously activating both arms of the immune system. Until now, most researchers have focused on one of two strategies: attacking tumors with antibodies, which activate the innate immune system, or stimulating T cells, which form the backbone of the adaptive immune system.

By combining these approaches, the MIT team was able to halt the growth of a very aggressive form of melanoma in mice.

“An anti-tumor antibody can improve adoptive T-cell therapy to a surprising extent,” says Dane Wittrup, the Carbon P. Dubbs Professor in Chemical Engineering at MIT. “These two different parts of the immune therapy are interdependent and synergistic.”

Wittrup, an associate director of MIT’s Koch Institute for Integrative Cancer Research and also a faculty member in the Department of Biological Engineering, is the senior author of a paper describing the work in Cancer Cell. Lead authors are graduate students Eric Zhu and Cary Opel and recent PhD recipient Shuning Gai.

Enlisting the immune system
Antibody drugs for cancer, which include rituximab and Herceptin, are believed to work by binding to cancer proteins and blocking the signals that tell cancer cells to divide uncontrollably. They may also draw the attention of cells belonging to the innate immune system, such as natural killer cells, which can destroy tumor cells.

Adoptive T cell therapy, on the other hand, enlists the body’s T cells to attack tumors. Billions of T cells flow through the average person’s bloodstream at any given time, each specialized to recognize different molecules. However, many tumor proteins do not provoke T cells to attack, so T cells must be removed from the patient and programmed to attack a specific tumor molecule.

Wittrup and his colleagues made the discovery that they could generate both types of immune responses while they were experimenting with improving antibody drug performance with a signaling molecule called IL-2, which helps boost immune responses.

Scientists have tried this strategy before, and about a dozen such therapies have gone through phase I clinical trials. However, most of these efforts failed, even though the antibody-IL-2 combination usually works very well against cancer cells grown in a lab dish.

The MIT team realized that this failure might be caused by the timing of IL-2 delivery. When delivered to cells in a dish, IL-2 sticks around for a long time, amplifying the response of natural killer cells against cancer cells. However, when IL-2 is injected into a patient’s bloodstream, the kidneys filter it out within an hour.

Wittrup and his colleagues overcame this by fusing IL-2 to part of an antibody molecule, which allows it to circulate in the bloodstream for much longer. In tests in mice with a very aggressive form of melanoma, the researchers found they could stop tumor growth by delivering this engineered form of IL-2, along with antibody drugs, once a week.

Immune synergy
To their surprise, the researchers found that T cells were the most important component of the anti-tumor response induced by the antibody-IL-2 combination. They believe that the synergy of IL-2-induced cells and cytokines, and the antibody treatment, creates an environment that lets T cells attack more effectively.

“The antibody-driven innate response creates an environment such that when the T cells come in, they can kill the tumor. In its absence, the tumor cells establish an environment where the T cells don’t work very well,” Wittrup says.

Cells called neutrophils, which are considered the immune system’s “first line of defense” because they react strongly to foreign invaders that enter the skin through a cut or other injury, were also surprisingly important.

“They’re a really powerful force in your immune system, but people in immunotherapy don’t usually focus on neutrophils. They don’t really consider them as a viable tool,” Zhu says. “It pointed us to the idea that although T cells and natural killer cells are important, maybe we’re forgetting about a part of the immune system that is also really important and could help us achieve our goals of ultimately curing the tumors.”

The researchers also found that when they delivered an antibody, IL-2, and T cells targeted to the tumor, the adoptively transferred T cells killed cancer cells much more successfully than when only T cells were delivered. In 80 to 90% of the mice, tumors disappeared completely; even when tumor cells were re-injected into the mice months after the original treatment, their immune systems destroyed the cells, preventing new tumors from forming

In a related paper that appeared recently in the Proceedings of the National Academy of Science, the MIT team also found that delivering IL-2 bound to any kind of antibody, even if the antibody did not target a protein on the tumor cell surface, would halt or slow tumor growth, especially if additional doses of the antibody alone were also given. Graduate student Alice Tzeng was the lead author of that study.

The researchers are now exploring additional proteins that could be added to the IL-2 and antibody combination to make immunotherapy more effective. In the meantime, simply giving patients more prolonged exposure to IL-2 could improve the effectiveness of existing antibody drugs, Wittrup says.

Source: Massachusetts Institute of Technology

ENTRIES OPEN:
Establish your company as a technology leader. For 50 years, the R&D 100 Awards, widely recognized as the “Oscars of Invention,” have showcased products of technological significance. Learn more.