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Of course we should expect to find bacteria in a healthy placenta. It only makes sense. But this is interesting stuff - the possibility that the placental biome being out of whack playing a role in preterm birth. From Medical Xpress:

Bacteria live even in healthy placentas, study finds

Surprising new research shows a small but diverse community of bacteria lives in the placentas of healthy pregnant women, overturning the belief that fetuses grow in a pretty sterile environment. These are mostly varieties of "good germs" that live in everybody. But the study also hints that the make-up of this microbial colony plays a role in premature birth.

We share our bodies with trillions of microbes—on the skin, in the gut, in the mouth. These communities are called our microbiome, and many bacteria play critical roles in keeping us healthy, especially those in the intestinal tract. Healthy newborns pick up some from their mother during birth, different bugs depending on whether they were delivered vaginally or by C-section. What about before birth?

Aagard's team earlier had studied the microbiome of the vagina, and learned that its composition changes when a woman becomes pregnant. The puzzle: The most common vaginal microbes weren't the same as the earliest gut bacteria that scientists were finding in newborns. What else, Aagaard wondered, could be "seeding" the infants' intestinal tract?

With colleagues from Baylor and Texas Children's Hospital, Aagaard analyzed 320 donated placentas, using technology that teases out bacterial DNA to evaluate the type and abundance of different microbes. The placenta isn't teeming with microbes—it harbors a low level, Aagaard stressed. Among them are kinds of E. coli that live in the intestines of most healthy people. But to Aagaard's surprise, the placental microbiome most resembled bacteria frequently found in the mouth, she reported in the journal Science Translational Medicine. The theory: Oral microbes slip into the mother's bloodstream and make their way to the placenta.

Why does the body allow them to stay? Aagaard said there appears to be a role for different microbes. Some metabolize nutrients. Some are toxic to yeast and parasites. Some act a bit like natural versions of medications used to stop preterm contractions, she said. In fact, among the 89 placentas that were collected after preterm births, levels of some of the apparently helpful bacteria were markedly lower, she said.

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Most of us are infected with human papilloma viruses. But the really interesting part is that the researchers found that the various HPV strains tend to interact, coexist, and offset symptoms in a balancing act - a HPV viral biome. From Medical Xpress:

More than two-thirds of healthy Americans are infected with human papilloma viruses

In what is believed to be the largest and most detailed genetic analysis of its kind, researchers at NYU Langone Medical Center and elsewhere have concluded that 69 percent of healthy American adults are infected with one or more of 109 strains of human papillomavirus (HPV). Only four of the 103 men and women whose tissue DNA was publicly available through a government database had either of the two HPV types known to cause most cases of cervical cancer, some throat cancers, and genital warts.

Researchers say that while most of the viral strains so far appear to be harmless and can remain dormant for years, their overwhelming presence suggests a delicate balancing act for HPV infection in the body, in which many viral strains keep each other in check, preventing other strains from spreading out of control. Although infection is increasingly known to happen through skin-to-skin contact, HPV remains the most common sexually transmitted infection in the United States. 

"Our study offers initial and broad evidence of a seemingly 'normal' HPV viral biome in people that does not necessarily cause disease and that could very well mimic the highly varied bacterial environment in the body, or microbiome, which is key to maintaining good health," says senior study investigator and NYU Langone pathologist Zhiheng Pei, MD, PhD. 

Lead study investigator and NYU Langone research scientist Yingfei Ma, PhD, says "the HPV 'community' in healthy people is surprisingly more vast and complex than previously thought, and much further monitoring and research is needed to determine how the various non-cancer-causing HPV genotypes interact with the cancer-causing strains, such as genotypes 16 and 18, and what causes these strains to trigger cancer."

Among the study's other key findings: - Some 109 of 148 known HPV types were detected in study participants. - Most study participants had HPV infections in the skin (61 percent); then vagina (41 percent), mouth (30 percent), and gut (17 percent). - Skin samples contained the most varied HPV strains (80 types of HPV, including 40 that were found only in the skin). Vaginal tissue had the second most numerous strains (43 types of HPV, with 20  exclusive to the organ), followed by mouth tissue (33 types, of which five were exclusively oral in origin), and gut tissue (six types, all of which were found in other organs).

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There has been much discussion lately on declining male sperm counts and what it means. From Medical Xpress:

No link found between low sperm count, birth defects

Having a low sperm count doesn't seem to determine whether a man's children will be born with birth defects, a new study indicates.

With infertile couples, men are partially or fully responsible for the inability to conceive about 40 percent of the time. Assisted reproductive technologies such as in vitro fertilization can help couples have children, but research has suggested a possible link between these approaches—when used to treat infertility problems in the male partner—and a higher risk of birth defects.

In the new study, researchers examined a Baylor College of Medicine database in search of possible connections between birth defects and low sperm count. The researchers didn't find any links.

But the following finding is a cause for concern. From Science Daily:

Male infertility linked to mortality, study shows

Men who are infertile because of defects in their semen appear to be at increased risk of dying sooner than men with normal semen, according to a study. Men with two or more abnormalities in their semen were more than twice as likely to die over a roughly eight-year period as men who had normal semen, the study found.

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Several interesting bacteria studies. Who knew that dental caries (tooth decay that causes cavities) is contagious? From Science Daily:

Bacteria can linger on airplane surfaces for days

Disease-causing bacteria can linger on surfaces commonly found in airplane cabins for days, even up to a week, according to research. In order for disease-causing bacteria to be transmitted from a cabin surface to a person, it must survive the environmental conditions in the airplane. In this study, MRSA lasted longest (168 hours) on material from the seat-back pocket while E. coli O157:H7 survived longest (96 hours) on the material from the armrest.

From Science Daily: Cavities are contagious, research shows

Dental caries, commonly known as tooth decay, is the single most common chronic childhood disease. In fact, it is an infectious disease, new research demonstrates. Mothers with cavities can transmit caries-producing oral bacteria to their babies when they clean pacifiers by sticking them in their own mouths or by sharing spoons. Parents should make their own oral health care a priority in order to help their children stay healthy.

From Science Daily: Physicians' stethoscopes more contaminated than palms of their hands

Although healthcare workers' hands are the main source of bacterial transmission in hospitals, physicians' stethoscopes appear to play a role. To explore this question, investigators assessed the level of bacterial contamination on physicians' hands and stethoscopes following a single physical examination. Two parts of the stethoscope (the tube and diaphragm) and four regions of the physician's hands (back, fingertips, and thenar and hypothenar eminences) were measured for the total number of bacteria present in a new study. The stethoscope's diaphragm was more contaminated than all regions of the physician's hand except the fingertips. Further, the tube of the stethoscope was more heavily contaminated than the back of the physician's hand.

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An exciting research study which finds that it is normal for bacteria to live in the bladders of healthy women, and that urine is not sterile. After further studies on the microbial communities in the bladder, perhaps bacterial treatments for various urinary problems? From Science Daily:

Study debunks common myth that urine is sterile: Bacterial differences found in urine of healthy women and women with overactive bladder

Bacteria live in the bladders of healthy women, discrediting the common belief that normal urine is sterile. This study also revealed that bladder bacteria in healthy women differ from the bladder bacteria in women affected by overactive bladder (OAB), which causes a sudden need to urinate.

Approximately 15 percent of women suffer from OAB and yet an estimated 40 -- 50 percent do not respond to conventional treatments. One possible explanation for the lack of response to medication may be the bacteria present in these women.

"If we can determine that certain bacteria cause OAB symptoms, we may be able to better identify those at risk for this condition and more effectively treat them," said Alan Wolfe, PhD, co-investigator and professor of Microbiology and Immunology, SSOM.

This study evaluated urine specimens of 90 women with and without OAB symptoms. Urine samples were collected through a catheter and analyzed using an expanded quantitative urine culture (EQUC) technique. This EQUC technique was able to find bacteria that are not identified by the standard urine culture techniques typically used to diagnose urinary tract syndromes.

Loyola researchers now plan to determine which bacteria in the bladder are helpful and which are harmful. They also will look at how these bacteria interact with each other and with their host, and how we can use this information to help patients. 

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Moderate levels of exercise seems to have tremendous benefits for everyone, but there are downsides to being an extreme exerciser.  From Science Daily:

Elderly men with high blood pressure lower death risk with moderate fitness

Elderly men with high blood pressure can lower their risk of death with even moderate levels of fitness. "This level of fitness is achievable by most elderly individuals engaging in a brisk walk of 20 to 40 minutes, most days of the week," said Charles Faselis, M.D., lead author of the study.

For the study, researchers assessed the fitness status of 2,153 men, aged 70 years and older with high blood pressure by a standard treadmill exercise test. Researchers applied the international units used to measure fitness, called metabolic equivalents (METs), to determine the men's peak fitness levels. After an average follow-up of nine years, researchers found that the risk of death was 11 percent lower for every one-MET increase in exercise capacity.

"For every 100 people who died in the least-fit category, 82 died in the low-fit, 64 in the moderate-fit and 52 in the high-fit categories," Kokkinos said. "The death rate is cut in half for those in the highest fitness category."

Too much exercise also has negatives for men. From Medical Xpress:

Too much prolonged high-intensity exercise risks heart health

Overdosing on high intensity exercise may actually increase the risk of death from a heart attack or stroke in those with existing heart disease, suggests German research published online in the journal Heart.

Similarly, a second Swedish study in the journal suggests that young men undertaking endurance exercise for more than five hours a week may increase their risk of developing an irregular heart rhythm in later life.

Both sets of findings indicate a J-shaped curve for the health benefits of exercise... And they describe "a similar U-shaped or reverse J-shaped pattern for the dose-response effect of exercise: maximum cardiovascular benefits are obtained if performed at moderate doses, while these benefits are lost with (very high) intensity and prolonged efforts."

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It seems that research showing benefits of exercise is multiplying. This study only looked at men, and if you look at the "after age 40 group", their average age of starting endurance training was 48. From Science Daily:

Forty not too old or too late to start endurance training

A study of healthy senior men has found that "relatively intensive" endurance exercise confers benefits on the heart irrespective of the age at which they began training. The benefits were evident and comparable in those who had started training before the age of 30 or after the age of 40. As a result, said the investigators, 40 is not too old to start endurance training.

The study was performed in 40 healthy men (without cardiovascular risk factors) aged between 55 and 70 years who were divided for assessment according to the level of exercise they took and the ages at which they began. Thus, 10 of the men had never exercised for more than 2 hours a week throughout their lives, and 30 had exercised for at least 7 hours a week for over five years.

The regular exercise they took was either running or cycling. Those beginning before the age of 30 had been training for an average of 39 years (since the age of 22) and those starting at 40 for 18 years (since the age of 48).

First, resting heart rate was found to be similar between the two exercise groups (T30 56.8 bpm, T40 58.1 bpm), but significantly faster in the non-exercising men (69.7 bpm). Maximal oxygen uptake was also similar between the T30 (47.3 ml/min/kg) and T40 groups (44.6 ml/min/kg), but significantly lower in the non-exercising men (33.0 ml/min/kg).

The study also found no difference between T30 and T40 in cardiac echocardiography tests. "Thus," said Matelot, "despite biological changes with age, the heart still seems -- even at the age of 40 -- amenable to modification by endurance training. Starting at the age of 40 does not seem to impair the cardiac benefits.

Matelot pointed out that aging is associated with adverse structural and functional changes to the cardiovascular system. And, while physical activity is unable to prevent these changes, it is able to slow them down.

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Once again research shows problems with physical inactivity: this time heart disease risk in women. From Science Daily:

From age 30 onwards, inactivity has greatest impact on women's lifetime heart disease risk

From the age of 30 onwards, physical inactivity exerts a greater impact on a woman's lifetime risk of developing heart disease than the other well-known risk factors, suggests research published online in the British Journal of Sports Medicine. This includes overweight. the findings show, prompting the researchers to suggest that greater effort needs to be made to promote exercise.

The researchers wanted to quantify the changing contribution made to a woman's likelihood of developing heart disease across her lifetime for each of the known top four risk factors in Australia: excess weight (high BMI); smoking; high blood pressure; and physical inactivity. Together, these four risk factors account for over half the global prevalence of heart disease, which remains the leading cause of death in high income countries.

They based their calculations on estimates of the prevalence of the four risk factors among 32,154 participants in the Australian Longitudinal Study on Women's Health, which has been tracking the long term health of women born in 1921-6, 1946-51, and 1973-8, since 1996.

Combining the prevalence and relative risk data, the researchers found that up to the age of 30, smoking was the most important contributor to heart disease, with a PAR of 59%. But from age 30 until the late 80s, low physical activity levels were responsible for higher levels of population risk than any of the other risk factors.

The researchers estimate that if every woman between the ages of 30 and 90 were able to reach the recommended weekly exercise quota -- 150 minutes of at least moderate intensity physical activity -- then the lives of more than 2000 middle aged and older women could be saved each year in Australia alone.

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Years ago the advice was to really limit exercise during pregnancy, but times have changed. Now studies find exercise during pregnancy beneficial for both the mother and baby. From Discover:

Exercise During Pregnancy Benefits Mom—And Baby, Too

Women who exercise with baby on board have been known to have, among other things, lower risks of gestational diabetes and pregnancy-induced high blood pressure than those who don’t.

In 1985, the American Congress of Obstetricians and Gynecologists came out with their first set of guidelines for exercise during pregnancy—guidelines, now considered conservative, that included suggestions like keeping strenuous activities to 15 minutes or less. Since then, research has turned that idea on its head. Exercise is now thought to be—for most women with healthy pregnancies—a boon for the mother's health, and for the baby she carries as well.

It’s been known that those who exercise—including pregnant women—tend to have lower resting heart rates than those who don’t. Lower heart rates can be a sign of an efficient heart; high heart rates have been linked to greater risk of cardiovascular disease. May, now at East Carolina University in North Carolina, has long been interested whether benefits like this extended to baby.  In a 2010 study, she and her colleagues collected a group of 26 pregnant women who reported that they’d been exercising three times a week for more than 30 minutes per session.  When researchers brought the moms into the lab at 36 weeks, they found that the babies in their bellies, too, had lower heart rates than those carried by the moms they studied who weren’t regular exercisers.

The results indicate that exercise during pregnancy, far from harming the fetus, can be incredibly beneficial for both mom and baby. And timing matters: exercise during pregnancy, as opposed to pre-pregnancy fitness, seems to be doing something extra-special, May says. In this most recent study, about half of the group hadn’t exercised previously, and still saw similar effects on their babies’ hearts. 

Such benefits to the heart may last into a child’s early life. Earlier this year, May and colleagues found that month-old infants still had higher heart rate variability if they had exercised along with their moms in utero. Another set of results from May’s group, not yet published, suggests that kids up to six years old still carry some of these early workouts with them: youngsters whose moms exercised while pregnant have higher “ejection fractions,” which indicates their hearts are pumping blood more efficiently.

Studies report that only about 10 to 30 percent of pregnant women are following recommended exercise guidelines—for healthy women, at least 30 minutes of moderate exercise most, if not all, days, according to the American Congress of Obstetricians and Gynecologists.. (Of course, some women can’t safely exercise during part or all of their pregnancy, and active women should watch out for warning signs while exercising, such as bleeding or contractions.)

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Please note that in the following study 200 grams is a measure of weight, and a little over a cup of many fruits and vegetables. Some examples: blueberries 1 cup=190 grams, green peas 1 cup=145 grams, but young salad greens 1 cup=20 grams. From Medical Daily:

Consuming Up To 200 Grams Of Fruits And Vegetables Will Decrease Your Stroke Risk

It’s not surprising that fruits and vegetables are the key to various health benefits, and now researchers are emphasizing their importance for reducing the risk of stroke.

In the study, researchers found that the stroke risk declined by 32 percent for the participants who ate 200 grams of fruit per day — and decreased by 11 percent for every 200 grams of daily vegetables. “Improving diet and lifestyle is critical for heart and stroke risk reduction in the general population,” Dr. Yan Qu, senior study author and director of the intensive care unit at Qingdao Municipal Hospital in China, said in a news release. “In particular, a diet rich in fruits and vegetables is highly recommended because it meets micronutrient and macronutrient and fiber requirements without adding substantially to overall energy requirements.”

Authors of the study reviewed 20 studies over the course of 19 years that involved over 760,000 people throughout the U.S., Asia, and Europe. The beneficial effects of fruits and vegetables were apparent across the board in both men and women.