Jeremy Singer-Vine
Blueberry extract slows the spread of a difficult-to-treat form of breast cancer, according to a small study of mice in Cancer Research. So-called triple-negative breast cancers, which account for 10% to 15% of all breast-cancer cases, lack the three receptors that most cancer drugs target. In a preliminary test-tube experiment, researchers discovered that blueberry extract, compared with other fruit and vegetable extracts, had the greatest effect on these tumors without harming healthy cells. The researchers randomized 16 mice to receive either blueberry extract—a daily dose of unadulterated juice extracted from blueberries that was roughly equivalent to five ounces of blueberries a day for a 150-pound person—or a placebo. One week after the first dose, the mice were injected with triple-negative breast-cancer cells. Six weeks after that, necropsies revealed that the tumors of blueberry-fed mice were about 70% smaller than those in placebo-fed mice. The tumors of the blueberry-fed mice also had less potential to spread to other parts of the body.
• Emotional Memory: Emotions can outlast the memory of the facts on which those feelings are based, according to a study of amnesiac patients in Proceedings of the National Academy of Sciences. Five patients with severe anterograde amnesia, which largely prevents the creation of new memories, watched a 19-minute video of film clips about death and loss. (The clips included scenes from "Sophie's Choice" and "Forrest Gump.") Several times during the study, researchers asked the subjects how they felt. Five to 10 minutes after the final scene, the amnesiacs remembered nearly nothing they had seen. They were asked to rate their emotions on several scales, including to what degrees they felt happy, sad, amused and "bad/unpleasant" versus "good/pleasant". The responses showed that the amnesiacs' negative emotions were stronger and lasted longer, than a control group of subjects who had no brain damage. The researchers repeated the experiment with humorous film clips, finding that positive emotions also outlasted specific memories. The results contradict the popular concept that "erasing" painful memories can ease the distress associated with those memories, the researchers said
Caveat: Larger studies are needed to confirm the findings. It's unclear whether emotions are equally persistent among people with other forms memory loss, such as Alzheimer's.
Read the Study: Sustained experience of emotion after loss of memory in patients with amnesia
• Pregnancy: Weight-reduction surgery appeared to reduce obese women's odds for blood-pressure disorders during future pregnancies, according to a study in BMJ. Obesity is a major risk factor for pregnancy-related hypertensive disorders, which can cause low birth weight and premature birth, as well as increase the mother's risk for cardiovascular and kidney diseases. Researchers examined insurance claims from 585 U.S. women who had weight-loss surgery and gave birth within a four-year window. About half of the women underwent the surgery before giving birth, with an average of two years between the two events. Fewer than 10% of these women experienced pre-eclampsia (a sudden spike in blood pressure and in protein in the urine) and other hypertensive disorders during pregnancy, while these complications occurred in 31% of women who delivered before weight-reduction surgery. Women who delivered pre-surgery were twice as likely to develop gestational diabetes, which may lead to Type 2 diabetes later in life.
Caveat: Researchers relied on insurance claims and didn't have access to the mothers' height, weight or blood pressure. They also were unable to link the data on mothers to their infants' health.
Read the Study: Impact of bariatric surgery on hypertensive disorders in pregnancy: retrospective analysis of insurance claims data;
• Immune Responses: Visual signs of disease, independent of physical proximity, appear to jump-start our immune systems, according to a study in Psychological Science. Researchers took blood samples from 28 subjects before and after they watched a 10-minute slide show depicting photographs of furniture, a neutral subject. Later, the researchers divided the same subjects into two groups; one watched a slide show of visible disease symptoms—including pictures of people sneezing or infected with skin lesions—while the other group saw photographs of guns. The white blood cells of participants in the first group produced nearly 24% more interleukin-6, a protein used to judge immune response, after seeing the photographs of disease. There was no statistically significant increase, however, in interleukin-6 after the furniture or gun slide shows.
Caveat: The study was small. It's unclear what effect these cues have in a non-laboratory setting, or in relation to other sensory signals.
• Emergency Care: Uninsured patients who have a heart attack, despite being guaranteed treatment, take significantly longer to arrive at the hospital than insured patients, according to a study in JAMA. Greater delays between a heart attack and hospital treatment decrease the odds of survival, previous studies have shown. Researchers in this study examined the medical records of 3,721 heart attack patients at 24 U.S. hospitals, and then interviewed them about their insurance status and financial concerns. One-fifth of all participants were uninsured. Of those, more than 48% arrived at the hospital six hours or longer after the heart attack occurred, compared with 39% of insured patients without financial concerns about their coverage, and about 45% of insured patients with financial concerns. After adjusting for a host of factors such as age and disability, the researchers determined that delays were nearly 40% more likely among uninsured patients than among patients with insurance and no financial concerns.
Caveat: Traffic and geographic distance from the hospital likely affected these delays, but the researchers were unable to collect this data. The researchers also didn't determine whether lack of insurance was a factor in patients themselves delaying going to the ER. The study was conducted solely in urban areas, so the findings don't necessarily apply to other regions.
Read the Study: Health Care Insurance, Financial Concerns in Accessing Care, and Delays to Hospital Presentation in Acute Myocardial Infarction
• Sexually Transmitted Infections: Human papillomavirus, known for its link to cervical cancer and other tumors, appears also to increase the risk of HIV infection, according to a study in PLoS ONE. Researchers followed 2,040 HIV-negative Zimbabwean women for approximately two years. Every three months, the women were tested for HIV and 29 known strains of HPV. About one-quarter of the women had HPV at the beginning of the study. By the end of the study, 88 women (4.3%) developed HIV. But women who began with either of two particular HPV strains were twice as likely as other women to acquire HIV. Remarkably, women with the least persistent HPV infections were the most likely to get HIV. These findings suggests that the immune response to HPV—rather than abnormal cell growth—predisposes women to HIV infection, the researchers said.
Caveat: Unlike other strains of HPV, vaccines aren't available for the types associated with HIV infection. The researchers were unable to distinguish between biologically active HPV and inactive virus DNA deposited by a recent sexual partner.
• Migraines: Aspirin can provide adequate relief for many migraine sufferers who lack access to prescription medication, according to meta-analysis by the Cochrane Library. The authors analyzed results from 4,222 participants in 13 studies that compared the effectiveness of aspirin—alone or in tandem with a generic anti-nausea drug—with a placebo. Within two hours, one-gram doses of aspirin reduced the severity of migraine headaches in 52% of participants, while a placebo worked for only one-third of migraneurs. Aspirin also significantly reduced nausea and vomiting, which the addition of the anti-nausea drug further diminished.
Caveat: Frequent aspirin use can cause stomach and intestinal ulcers, and may contribute to hearing loss and other symptoms. As with all meta-analyses, the underlying studies have their own limitations.
Read the Study: Aspirin with or without an antiemetic for acute migraine headaches in adults
• Digestion: An intestinal bacterium apparently abundant among Japanese has evolved to improve the digestion of seaweed, according to a study in Nature. The human gut harbors trillions of bacteria, many of which help digest molecules that human enzymes cannot. Researchers identified a new class of enzyme that breaks down porphyran, a carbohydrate found exclusively in red algae. They then tested intestinal bacteria samples from 13 Japanese volunteers and 18 North American volunteers for the genetic sequence that creates the porphyran-breaking enzyme. The gene was common in the Japanese samples, but entirely absent from the North American samples. This string of DNA likely migrated from marine microbes to intestinal bacteria, though it's difficult to estimate when this happened, the researchers said.
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