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Published on Leave a comment on Similar Fertility Decline In Both Dogs and Men

Take note: what is happening to dogs is also happening to men. Specifically, for many decades - year by year - there has been a decrease in male dog fertility. And yes, this is also happening with human male fertility - a decline in male semen quality (including sperm), along with an increase in the incidence of testicular cancer, the birth defect hypospadias, and undescended testes. This cluster of problems is called testicular dysgenesis syndrome (TGS), and it has an negative impact on male fertility.

Dr Richard Lea, who led the research said: "This is the first time that such a decline in male fertility has been reported in the dog and we believe this is due to environmental contaminants..." and "While further research is needed to conclusively demonstrate a link, the dog may indeed be a sentinel for humans -- it shares the same environment, exhibits the same range of diseases, many with the same frequency, and responds in a similar way to therapies."

What chemicals were detected that affect male fertilty? Why, the same chemicals that appear again and again in studies and are linked to a number of health problems: endocrine disruptors. Yes, they are all around us - in our food, our homes, our everyday products, our environment. From Science Daily:

Study demonstrates rapid decline in male dog fertility, with potential link to environmental contaminants

A study led by researchers at The University of Nottingham has discovered that the fertility of dogs may have suffered a sharp decline over the past three decades. The research, published in the academic journal Scientific Reports, found that sperm quality in a population of stud dogs studied over  a 26-year period had fallen significantly.The work has highlighted a potential link to environmental contaminants, after they were able to demonstrate that chemicals found in the sperm and testes of adult dogs -- and in some commercially available pet foods -- had a detrimental effect on sperm function at the concentrations detected.

 The study centered on samples taken from stud dogs at an assistance dogs breeding center over the course of 26 years. Professor Gary England.... said: "The strength of the study is that all samples were processed and analysed by the same laboratory using the same protocols during that time and consequently the data generated is robust." The work centred on five specific breeds of dogs -- Labrador retriever, golden retriever, curly coat retriever, border collie and German shepherd -- with between 42 and 97 dogs studied every year. Semen was collected from the dogs and analysed to assess the percentage of sperm that showed a normal forward progressive pattern of motility and that appeared normal under a microscope (morphology).

Over the 26 years of the study, they found a striking decrease in the percentage of normal motile sperm. Between 1988 and 1998, sperm motility declined by 2.5 per cent per year and following a short period when stud dogs of compromised fertility were retired from the study, sperm motility from 2002 to 2014 continued to decline at a rate of 1.2% per year. In addition, the team discovered that the male pups generated from the stud dogs with declining semen quality, had an increased incidence of cryptorchidism, a condition in which the testes of pups fail to correctly descend into the scrotum.

Sperm collected from the same breeding population of dogs, and testes recovered from dogs undergoing routine castration, were found to contain environmental contaminants at concentrations able to disrupt sperm motility and viability when tested. The same chemicals that disrupted sperm quality, were also discovered in a range of commercially available dog foods -- including brands specifically marketed for puppies. Dr Lea added: "We looked at other factors which may also play a part, for example, some genetic conditions do have an impact on fertility. However, we discounted that because 26 years is simply too rapid a decline to be associated with a genetic problem."

Over the past 70 years, studies have suggested a significant decline in human semen quality and a cluster of issues called 'testicular dysgenesis syndrome' that impact on male fertility which also include increased incidence of testicular cancer, the birth defect hypospadias and undescended testes.

However, declining human semen quality remains a controversial issue -- many have criticised the variability of the data of the studies on the basis of changes in laboratory methods, training of laboratory personnel and improved quality control over the years. Dr Lea added: "The Nottingham study presents a unique set of reliable data from a controlled population which is free from these factors. This raises the tantalising prospect that the decline in canine semen quality has an environmental cause and begs the question whether a similar effect could also be observed in human male fertility."

Excerpts from the original study in Scientific Reports: Environmental chemicals impact dog semen quality in vitro and may be associated with a temporal decline in sperm motility and increased cryptorchidism

A significant decline in human semen quality over the last 70 years has been widely reported1,2. The first meta-analysis reporting this phenomenon included 61 studies selected over a 50 year period (1938–1991)1 and such a trend was confirmed by re-analysis with an additional 47 studies included2.....Nevertheless, reports of declining sperm counts linked with epidemiological data on increased incidences of testicular cancer and genital tract abnormalities, is indicative of an adverse environmental effect on male reproduction6,7,8. Since these reproductive problems, termed by some as “testicular dysgenesis syndrome” (TDS), cluster in geographical areas9 they are thought to have a common aetiology and have been associated with endocrine perturbations in early life10. Exposure of developing males to environmental chemicals, particularly those with endocrine disrupting activity, is thought to be the initiator11. Although periods of development particularly sensitive to exposure encompass both pre-natal and pre-pubertal periods, environmental chemicals also perturb adult testis function e.g. gene expression and meiosis12. 

As ‘man’s best friend’ and closest animal companion, the dog shares the same environment, exhibits the same range of diseases, many with the same frequency, and responds in a similar way to therapeutic treatments. There is evidence that over the last 40 years, the incidence rate of canine testicular cancer has increased in parallel with changes seen in humans17,18. In addition, histological signs which characterise human TDS have recently been described in the dog19. These include seminiferous tubule abnormalities and testicular germ cell neoplasia in situ (GCNIS) cells which are known precursors of seminomas in the human20. Since human TDS includes a reduction in sperm count21 and an increased incidence of cryptorchidism, we hypothesised that the dog may exhibit similar manifestations of TDS and that this may be associated with exposure to endocrine disrupting chemicals.  

The dog is probably man’s closest companion and by sharing the same habitat, is likely to be exposed to similar environmental conditions including environmental chemicals. This was especially true in the current study since the dogs lived in homes with their handlers. Twelve chemicals detected in adult dog testes (DEHP, 7 PCB congeners, 4 PBDE congeners) were also detected in the 15 commercially available dog foods analysed. 

Published on Leave a comment on Strong Evidence That Alcohol Causes Seven Cancers

A medical article in the journal Addiction states that there is strong evidence that alcohol causes 7 cancers, that there is evidence that it probably causes more, the effects are dose related, and if one also smokes the risks are greatly increased. The 7 cancers are: oropharynx (mouth and pharynx), larynx, esophagus, liver, colon, rectum, and female breast.

An earlier post reported on conflicting results from some studies (e.g. that low to moderate alcohol consumption is beneficial), as well as the finding that effects are dose-related (the more alcohol a person drinks, the higher the risk of cancer). NOTE: One standard drink contains 14 grams of alcohol, and is equivalent to one ordinary beer, a glass of wine (5 oz), or a nip of spirits (1.5 oz or 44 ml). The article excerpts below state that the strongest effects are from consuming 50 grams or more of alcohol per day (compared to those who don't drink at all).

From Medscape: No Confusion: Alcohol Causes Seven Cancers

There is "strong evidence" that alcohol causes seven cancers, and other evidence indicates that it "probably" causes more, according to a new literature review published online July 21 in Addiction. Epidemiologic evidence supports a causal association of alcohol consumption and cancers of the oropharynx, larynx, esophagus, liver, colon, rectum, and female breast, says Jennie Connor, MB, ChB, MPH, from the Department of Preventive and Social Medicine, University of Otago, in Dunegin, New Zealand.

In short, alcohol causes cancer. This is not news, says Dr Connor. The International Agency for Research on Cancer (IARC) and other agencies have long identified alcohol consumption as being causally associated with these seven cancers. So why did Dr Connor, who is an epidemiologist and physician, write a new review? Because she wants to "clarify the strength of the evidence" in an "accessible way." 

The newly published review "reinforces the need for the public to be made aware of the causal link between alcohol and cancer," said Colin Shevills, from the Alcohol Health Alliance UK, in a press statement....The lack of clarity about alcohol causing cancer, Dr Connor believes, is related to alcohol industry propaganda as well as the fact that the "epidemiological basis for causal inference is an iterative process that is never completed fully."

Dr Connor writes that the strength of the association of alcohol as a cause of cancer varies by bodily site. The evidence is "particularly strong" for cancer of the mouth, pharynx, and esophagus (relative risk, ~4-7 for ≥50 g/day of alcohol compared with no drinking) but is less so for colorectal cancer and liver and breast cancer (relative risk, ~1.5 for ≥50 g/day). "For cancers of the mouth, pharynx, larynx and oesophagus there is a well-recognized interaction of alcohol with smoking, resulting a multiplicative effect on risk," adds Dr Connor.

Other cancers are also likely caused by alcohol. Dr Connor writes that there is "accumulating research" supporting a causal contribution of alcohol to cancer of the pancreas, prostate, and skin (melanoma). One British expert had an opinion about alcohol's carcinogenicity. In a statement about the new review, Prof Dorothy Bennett, director of the Molecular and Clinical Sciences Research Institute at St. George's, University of London, said: "Alcohol enters cells very easily, and is then converted into acetaldehyde, which can damage DNA and is a known carcinogen."

In the new review, Dr Connor describes various hallmarks of causality that have been found in epidemiologic studies of alcohol and these seven cancers, such as a dose-response relationship and the fact that the risk for some of these cancers (esophageal, head and neck, and liver) attenuates when drinking ceases. Current estimates suggest that alcohol-attributable cancers at the seven cancer sites make up 5.8% of all cancer deaths worldwide, she states. The alcohol industry has a lot at stake, she says, which in turn leads to "misinformation" that "undermines research findings and contradicts evidence-based public health messages."

But there is no safe level of drinking with respect to cancer, says Dr Connor, citing research about low to moderate levels of alcohol, which has been covered by Medscape Medical News. This was also the conclusion of the 2014 World Cancer Report, issued by the World Health Organization's IARC.

Published on Leave a comment on Tart Cherry Juice May Aid Recovery After Intense Exercise

Image result for cherries wikipedia Another study reporting health benefits of drinking tart cherry juice, specifically in speeding recovery following prolonged, repeat sprint activity (think soccer and rugby). The researchers found that after a prolonged, intermittent sprint activity, the cherry juice significantly lowered levels of Interleukin-6, a marker for inflammation and that there was a decrease in muscle soreness.  The study participants drank the cherry juice (1 oz cherry juice concentrate mixed with 100 ml water) for several days before and several days after the sprint activity. Montmorency tart cherry juice is a polyphenol rich food that is already used by many professional sports teams to aid recovery. From Medical Xpress:

New study: Montmorency tart cherry juice found to aid recovery of soccer players

Montmorency tart cherry juice may be a promising new recovery aid for soccer players following a game or intense practice. A new study published in Nutrients found Montmorency tart cherry juice concentrate aided recovery among eight semi-professional male soccer players following a test that simulated the physical and metabolic demands of a soccer game .The U.K. research team, led by Glyn Howatson at Northumbria University, conducted this double-blind, placebo-controlled study to identify the effects of Montmorency tart cherry juice on recovery among a new population of athletes following prolonged, intermittent exercise..... many teams in professional and international soccer and rugby already use Montmorency tart cherry juice to aid recovery."

The study involved 16 semi-professional male soccer players aged 21 to 29 who were randomly assigned to either a Montmorency tart cherry concentrate group or a placebo control group. Montmorency group participants consumed about 1 ounce (30 ml) of a commercially available Montmorency tart cherry juice concentrate mixed with 100 ml of water twice per day (8 a.m. and 6 p.m.) for seven consecutive days—for four days prior to the simulated trial and for three days after the trial. Following the same schedule, placebo group participants consumed a calorie-matched fruit cordial with less than 5 percent fruit mixed with water and maltodextrin. The 30 ml dosage of Montmorency tart cherry juice concentrate contained a total anthocyanin content of 73.5 mg, or the equivalent of about 90 whole Montmorency tart cherries.

Montmorency tart cherry juice, compared to a placebo, was found to maintain greater functional performance, impact a key marker of inflammation and decrease self-reported muscle soreness among study participants following prolonged activity that mirrors the demands of field-based sports. While additional research is needed, the authors suggest the dampening of the post-exercise inflammatory processes may be responsible.

Across every performance measure, including maximal voluntary isometric contraction, countermovement jump height, 20 m sprint time, knee extensors, 5-0-5 agility, the Montmorency group showed better performance than the placebo group. Additionally, the Montmorency group showed significantly lower levels of Interleukin-6, a marker for inflammation, particularly immediately post-trial. Ratings for muscle soreness (DOMS) were significantly lower in the Montmorency group across the 72-hour post-trial period. No significant effects in muscle damage or oxidative stress were observed in either the Montmorency group or the placebo group. These data support previous research showing similar results for athletes performing marathon running, high-intensity strength training, cycling, and metabolic exercise. 

Published on Leave a comment on Does Saline Nasal Irrigation Treat Sinusitis Symptoms?

A recent study compared saline nasal irrigation vs steam inhalation vs doing both saline irrigation and steam inhalation vs doing neither (the control group) for chronic or recurring sinusitis symptoms. In the study, people with a history of chronic or recurring sinusitis symptoms were randomly assigned to one of the 4 groups, and then studied 3 months and 6 months later. The results were: a modest (slight improvement) in the saline irrigation group in symptom and quality-of-life scores, but no improvement for the steam inhalation group. However, the researchers noted that the control group also had slight improvements at 3 and 6 months. Most of the improvement in the saline irrigation group was in the group that also did steam inhalation - thus perhaps some benefit to combining both.

In addition, patients in the nasal irrigation group reported fewer headaches, fewer of them used over-the-counter medications, and said they were less likely to consult with a physician about their nasal problems in the future when compared with patients in the steam inhalation group.

Most people with chronic or recurring sinusitis will probably agree with the findings. Yes, effects are modest with saline irrigation, but it definitely does improve nasal stuffiness (experiences of family members and readers). But it does NOT treat the sinusitis. The sinus microbial community continues to stay out of whack (dysbiosis). Which explains the researchers' finding that saline irrigation and steam inhalation did not result in differences in antibiotic use or physician visits after 6 months.

From Science Daily: Nasal irrigation may prevent chronic sinus ailments

Advising patient with chronic sinus congestion to use nasal irrigation -- a popular nonpharmacologic treatment -- improved their symptoms, but steam inhalation did not, according to a randomized controlled trial published in CMAJ(Canadian Medical Association Journal). More than 25 million people in the United States and about 2.5 million Canadians suffer from chronic rhinosinusitis, or sinus infection, and experience compromised quality of life. To alleviate symptoms, steam inhalation and nasal irrigation are widely suggested as an alternative to common treatment with antibiotics, which are often not effective and contribute to antibiotic resistance.

Researchers from the United Kingdom conducted a randomized controlled trial on the effectiveness of advice from primary care physicians to use nasal irrigation and/or steam inhalation for chronic sinusitis. The study involved 871 patients from 72 primary care practices in England who were randomly assigned to 1 of 4 advice strategies: usual care, daily nasal and saline irrigation supported by a demonstration video, daily steam inhalation, or combined treatment with both interventions.

Patients who were instructed to use nasal irrigation showed improvement at 3 and 6 months, as measured by the Rhinosinusitis Disability Index. Steam inhalation did not appear to alleviate symptoms of sinusitis.

"We found potentially important changes in other outcomes; in particular, fewer participants in the nasal irrigation group than in the no-irrigation group had headaches, used over-the-counter medications and intended to consult a doctor in future episodes," write the authors. "Although there was no significant difference in either physician visits or antibiotic use, as might be expected over only a 6-month follow-up period, our findings concerning consultations are important in the longer term, given antibiotic use increases the risk of antimicrobial resistance."

The Abstract (summary) of the study, which is from the Canadian Medical Association Journal (CMAJ): Effectiveness of steam inhalation and nasal irrigation for chronic or recurrent sinus symptoms in primary care: a pragmatic randomized controlled trial

ABSTRACT  Background: Systematic reviews support nasal saline irrigation for chronic or recurrent sinus symptoms, but trials have been small and few in primary care settings. Steam inhalation has also been proposed, but supporting evidence is lacking. We investigated whether brief pragmatic interventions to encourage use of nasal irrigation or steam inhalation would be effective in relieving sinus symptoms.

Methods: We conducted a pragmatic randomized controlled trial involving adults (age 18–65 yr) from 72 primary care practices in the United Kingdom who had a history of chronic or recurrent sinusitis and reported a “moderate to severe” impact of sinus symptoms on their quality of life. Participants were recruited between Feb. 11, 2009, and June 30, 2014, and randomly assigned to 1 of 4 advice strategies: usual care, daily nasal saline irrigation supported by a demonstration video, daily steam inhalation, or combined treatment with both interventions. The primary outcome measure was the Rhinosinusitis Disability Index (RSDI). Patients were followed up at 3 and 6 months. We imputed missing data using multiple imputation methods.

Results: Of the 961 patients who consented, 871 returned baseline questionnaires (210 usual care, 219 nasal irrigation, 232 steam inhalation and 210 combined treatment). A total of 671 (77.0%) of the 871 participants reported RSDI scores at 3 months. Patients’ RSDI scores improved more with nasal irrigation than without nasal irrigation by 3 months (crude change −7.42 v. −5.23; estimated adjusted mean difference between groups −2.51, 95% confidence interval −4.65 to −0.37). By 6 months, significantly more patients maintained a 10-point clinically important improvement in the RSDI score with nasal irrigation (44.1% v. 36.6%); fewer used over-the-counter medications (59.4% v. 68.0%) or intended to consult a doctor in future episodes. Steam inhalation reduced headache but had no significant effect on other outcomes. The proportion of participants who had adverse effects was the same in both intervention groups.

Interpretation: Advice to use steam inhalation for chronic or recurrent sinus symptoms in primary care was not effective. A similar strategy to use nasal irrigation was less effective than prior evidence suggested, but it provided some symptomatic benefit.

Published on Leave a comment on Twin Study Finds Being Overweight Not Linked To Early Death or Heart Attack

Another interesting study looking at whether being overweight is linked to premature death, heart attacks, and diabetes. This study looked at sets of twins, in which one is heavier than the other, and followed them long-term (average 12.4 years) and found that NO - being overweight or obese (as measured by Body Mass Index or BMI) is NOT associated with premature death or heart attack (myocardial infarction), but it is associated with higher rates of type 2 diabetes. These results are in contrast with what a large study recently found. From Science Daily:

Higher BMI not associated with increased risk of heart attack or early death, twin study shows

A study of 4,046 genetically identical twin pairs with different amounts of body fat shows that twin siblings with a higher Body Mass Index, as a measure of obesity, do not have an increased risk of heart attack or mortality. The study, conducted by researchers at Umeå University in Sweden, also shows that a higher BMI is associated with an increased risk of type 2 diabetes...."The results suggest that lifestyle changes that reduce levels of obesity do not have an effect on the risk of death and heart attack, which contradicts conventional understandings of obesity-related health risks," says Peter Nordström, researcher at the Department of Community Medicine and Rehabilitation at Umeå University.

In the cohort study, Peter Nordström and research colleagues at Umeå University compared health data from 4,046 monozygotic twin pairs. All twins in the study had different levels of body fat, as measured in BMI....During a follow-up period of on average 12.4 years, differences between the twins were compared when it comes to incidents of mortality, heart attack and type 2 diabetes. The results clearly showed that twin siblings with a higher BMI did not have an increased risk of mortality or heart attack compared to their thinner counterparts. However, twins with a higher BMI did have an increased risk of developing type 2 diabetes.

The results showed that: - Among twin siblings with a higher BMI (mean value 25.1), there were 203 heart attacks (5 %) and 550 deaths (13.6 %) during the follow-up period. - Among twin siblings with a lower BMI (mean value 23.9), there were 209 heart attacks (5.2 %) and 633 deaths (15.6 %) during the same period. - Among the 65 twin pairs in the study who had a BMI difference of 7 or higher, and where the larger twin siblings had a BMI of 30 or higher, there were still no noticeably increased risk of mortality or heart attack associated with a higher BMI.

The study, described in the article Risks of Myocardinal Infarction, Death, and Diabetes in Identical Twin Pairs With Different Body Mass Index, is based on the Swedish Twin Registry, the largest of its kind in the world. The median age of the twins in the study was 57.5 and participants' ages ranged from 42-92. The cohort study was conducted between 1998 and 2003, with follow-ups regarding incident of mortality, heart attack and diabetes during a 10 year period until 2013. One study limitation was that weight and length (used to calculate BMI) was self-reported.

Published on Leave a comment on Frequent Nut Consumption Has Health Benefits

Studies have found that increased nut consumption has been associated with reduced risk of cardiovascular disease and type 2 diabetes. A newly published study looked at large groups of people to see if this was due to nuts reducing systemic inflammation throughout the body - which can be measured by inflammatory biomarkers such as C-reactive protein (CRP) and  interleukin 6 (IL6).

The researchers found that nut consumption was inversely associated with concentrations of biomarkers CRP and IL-6 - that is, the more nuts eaten weekly, the lower the inflammatory biomarkers. They also found that substituting nuts for red meat, processed meat, eggs, refined grains, potatoes, or potato chips was associated with a healthier inflammatory biomarker profile. In the study, one serving of nuts was equivalent to 28 g (1 oz) of peanuts or other nuts. What's in nuts? Unsaturated fatty acids, high quality plant protein, fiber, minerals, vitamins, bioactive compounds such as phytosterols, antioxidants, magnesium, etc. Bottom line: eat a serving of nuts at least several times a week. From Science Daily:

Frequent nut consumption associated with less inflammation

In a study of more than 5,000 people, investigators from Brigham and Women's Hospital have found that greater intake of nuts was associated with lower levels of biomarkers of inflammation, a finding that may help explain the health benefits of nuts. The results of the study appear July 27 in the American Journal of Clinical Nutrition.

"Population studies have consistently supported a protective role of nuts against cardiometabolic disorders such as cardiovascular disease and type 2 diabetes, and we know that inflammation is a key process in the development of these diseases," said corresponding author Ying Bao, MD, ScD, an epidemiologist in BWH's Channing Division of Network Medicine. "Our new work suggests that nuts may exert their beneficial effects in part by reducing systemic inflammation."

Previously Bao and her colleagues observed an association between increased nut consumption and reduced risk of major chronic diseases and even death, but few prospective cohort studies had examined the link between nut intake and inflammation. In the current study, the research team performed a cross-sectional analysis of data from the Nurses' Health Study, which includes more than 120,000 female registered nurses, and from the Health Professionals Follow-Up Study, which includes more than 50,000 male health professionals.... looked at the levels of certain telltale proteins known as biomarkers in blood samples collected from the study participants. They measured three well-established biomarkers of inflammation: C-reactive protein (CRP), interleukin 6 (IL6) and tumor necrosis factor receptor 2 (TNFR2).

After adjusting for age, medical history, lifestyle and other variables, they found that participants who had consumed five or more servings of nuts per week had lower levels of CRP and IL6 than those who never or almost never ate nuts. In addition, people who substituted three servings per week of nuts in place of red meat, processed meat, eggs or refined grains had significantly lower levels of CRP and IL6.

Peanuts and tree nuts contain a number of healthful components including magnesium, fiber, L-arginine, antioxidants and unsaturated fatty acids such as α-linolenic acid. Researchers have not yet determined which of these components, or if the combination of all of them, may offer protection against inflammation, but Bao and her colleagues are interested in exploring this further through clinical trials that would regulate and monitor diet.

Published on Leave a comment on E-Cigarettes Emit Varying Amounts of Harmful Chemicals

Yup, e-cigarettes are NOT harmless, but emit harmful compounds. Researchers detected significant levels of 31 chemical compounds, including nicotine, nicotyrine, formaldehyde, acetaldehyde, glycidol, acrolein, acetol, and diacetyl. Included in the harmful emissions are carcinogens and respiratory irritants. From Science Daily:

All e-cigarettes emit harmful chemicals, but some emit more than others

While previous studies have found that electronic cigarettes emit toxic compounds, a new study from Lawrence Berkeley National Laboratory (Berkeley Lab) has pinpointed the source of these emissions and shown how factors such as the temperature, type, and age of the device play a role in emission levels, information that could be valuable to both manufacturers and regulators seeking to minimize the health impacts of these increasingly popular devices.

The study, which was published in Environmental Science & Technology, found that the thermal decomposition of propylene glycol and glycerin, two solvents found in most "e-liquids" (the substance that is vaporized by the e-cigarette), leads to emissions of toxic chemicals such as acrolein and formaldehyde.

"Advocates of e-cigarettes say emissions are much lower than from conventional cigarettes, so you're better off using e-cigarettes," said Berkeley Lab researcher and the study's corresponding author Hugo Destaillats. "I would say, that may be true for certain users--for example, long time smokers that cannot quit--but the problem is, it doesn't mean that they're healthy. Regular cigarettes are super unhealthy. E-cigarettes are just unhealthy."

One finding was that the first and last puffs produce widely varying emissions. Using a custom-built vaping apparatus emulating realistic vaping habits, researchers drew on the e-cigarette by taking puffs lasting 5 seconds every 30 seconds. They found that vapor temperature rose quickly in the first 5 to 10 minutes until reaching a steady state temperature at around the twentieth puff. Correspondingly, emissions levels between the first few puffs and the steady state increased by a factor of 10 or more in some cases, depending on the device, the battery voltage, and the emitted compound

Because there is an immense variety of e-cigarettes as well as e-liquids, the Berkeley Lab researchers decided to focus on an element that is common to all of them: the solvent in the e-liquid. Almost all e-liquids use a combination of propylene glycol and glycerin in varying proportions as a solvent....The researchers vaporized liquids consisting solely of the solvents to verify that they were the source of the emissions. In all, the researchers detected significant levels of 31 harmful chemical compounds, including two that had never been previously found in e-cigarette vapor--propylene oxide and glycidol, both of which are probable carcinogens.

Published on Leave a comment on New Antibiotic Or Future Probiotic?

 Some people have nasal bacteria - Staphylococcus lugdunensis, that kills other disease causing bacteria such as Staphylococcus aureus (including strains of MRSA) and Enterococcus. This is because S. lugdunensis produces a molecule (lugdunin) that acts as an antibiotic. It is thought that 10% of people naturally carry S. lugdunensis in their nasal passages. Will this lead to a new class of antibiotics or to probiotics of the future? Could it help in treating sinusitis? Stay tuned... From Science News:

The nose knows how to fight staph

The human nose harbors not only a deadly enemy — Staphylococcus aureus — but also its natural foe. Scientists have now isolated a compound from that foe that might combat MRSA, the methicillin-resistant strain of S. aureus....Investigating the intense interspecies competition in the nose — where microbes fight for space and access to scant sugars and amino acids — might offer a fertile alternative to searching for new drug candidates in soil microbes.

Despite being a relatively nutrient-poor environment, the human nose is home to more than 50 species of bacteria. One of these is S. aureus, a dominant cause of hospital-acquired infections such as MRSA, as well as infections of the blood and heart. But there’s a huge variability in the nasal microbe scene between individuals: while S. aureus is present in the nasal passages of roughly 30 percent of people, the other 70 percent don’t have any sign of it.

Trying to explain this difference led Peschel and colleagues to study “the ecology of the nose.” They suspected that other nasal inhabitants, well-tuned to compete in that harsh niche, might be blocking S. aureus from colonizing the nose in those who don’t carry it. From nasal secretion samples, the team isolated 90 strains of different Staphylococcus species. Of these, one bacterium, S. lugdunensis, killed S. aureus when the two were grown together in a dish. Introducing a variety of mutations into S. lugdunensis produced a strain that didn’t kill. The missing gene, the team showed, normally produced an antibiotic, which the researchers named lugdunin; it represents the first example of a new class of antibiotic.

Lugdunin was able to fend off MRSA as well as a strain of Enterococcus resistant to the antibiotic vancomycin. Neither bacteria developed resistance. The team also pitted S. lugdunensis against S. aureus in test tube and mouse studies, with S. lugdunensis besting S. aureus. Only 5.9 percent of 187 hospital patients had S. aureus in their noses if they also carried S. lugdunensis, the team found, while S. aureus was present in 34.7 percent of those without S. lugdunensis. Peschel and colleagues also reported the results July 28 in Nature.

Lugdunin cleared up a staph skin infection in mice, but it’s unclear how the compound works. Researchers could not rule out that it damages the cell membrane, which could limit its use in humans to a topical antibiotic. Peschel and coauthor Bernhard Krismer also suggest that the bacterium itself might be a good probiotic, applied nasally, to fend off staph infections in vulnerable hospital patients.  (The original study and accompanying Commentary)

 A compound secreted by the nose-dwelling bacterium Staphylococcus lugdunensis may fight antibiotic-resistant strains of bacteria such as MRSA (pink). CREDIT: NIAID, NIH/WIKIMEDIA COMMONS

Published on Leave a comment on Children Share Their Cavity Causing Bacteria

Research shows that Streptococcus mutans, the bacteria that is a main cause of tooth decay or dental caries, is passed from mother to child, and also between nonrelative children. Any interaction that involves saliva, like sharing an ice cream cone or drinking from the same cup or straw as another child, can cause the microbes to be transferred. From Medical Xpress:

Research shows sharing of cavity-causing bacteria may not be only from mothers to children

New ongoing research from the University of Alabama at Birmingham Department of Biology and School of Dentistry is showing more evidence that children may receive oral microbes from other, nonrelative children. It was previously believed that these microbes were passed primarily from mother to child, but in a recent study presented at the American Society for Microbiology MICROBE 2016 Meeting in Boston, researchers found that 72 percent of children harbored at least one strain of the cavity-causing Streptococcus mutans not found in any cohabiting family members.

S. mutans is a bacterium that feeds on fermentable carbohydrates, in particular sucrose, that are frequently consumed by humans. After meals, S. mutans produces enamel-eroding acids, which makes S. mutans one of the main causes of tooth decay, or dental caries, in humans.

One hundred nineteen African-American children ages 12-18 months and 5-6 years who lived with at least one family member were a part of the study. The researchers collected samples from children periodically over the course of eight years. Momeni says that dental caries are more prevalent in minorities and low-socioeconomic groups.

"The literature tells us that we usually get this bacterium from our mothers," Momeni said. "This is because we most commonly have more interaction with our mothers when we are very young. However, our data supports that children who interact with other children at school or in nurseries can, and frequently do, contract this bacteria from each other." Momeni says any interaction that involves saliva, like sharing an ice cream cone or drinking after another child from the same cup or straw, can cause the microbes to be transferred.

Forty percent of the children in the study did not share any S. mutans strains with their mothers, and close to 20 percent of children shared these bacteria only with another child who lived in the household, such as a sibling or cousin. It is important to note that, for the strains of S. mutans not shared with anyone in the same household, approximately a third of the children had only a single isolate for a genotype, which could mean these rare strains may have nothing to do with the dental caries, and may be confounding the search for strains associated with the disease.

Published on Leave a comment on Exercise Instead of Meniscus Repair Surgery?

A new study followed adults with meniscus tears (in the knee), who were randomly assigned to either exercise only or meniscus repair surgery (arthroscopic partial meniscectomy) only. They found that after 2 years there was no difference between those  who just received exercise therapy compared to those who just received meniscus repair surgery. About 19% of the exercise only group decided to get surgery at some point, but the rest stayed in the exercise only group.

The study in BMJ says that the exercise therapy program consisted of progressive neuromuscular and strength exercises over 12 weeks, which were performed between two and a maximum of three sessions each week (24-36 sessions). Once again, a study shows that surgery for a condition may not be necessary. From Science Daily:

Most surgical meniscus repairs are unnecessary

Three out of four people could avoid knee surgery with a new form of exercise therapy, with significant cost savings for society. Injury to the menisci, the cartilaginous discs within the knee joint, can be painful when running, and can cause the knee to give way or 'lock'. Such injuries are troublesome and sometimes painful, and can prevent you from exercising or attending work. A new study shows that exercise therapy is just as effective for treating meniscus injuries as surgery. .

A total of 140 patients with meniscus injuries in Norway and Denmark took part in the study. They drew lots for treatment with either exercise or surgery. Nina Jullum Kise says, "Two years later, both groups of patients had fewer symptoms and improved functioning. There was no difference between the two groups." However, those who had exercised had developed greater muscular strength. This is consistent with previous research, which showed that surgery yielded no additional benefits for patients who had had exercise therapy.... Jullum Kise believes that as many as three in four could be spared surgery with the right exercise therapy programme. 

In the study, the patients attended training sessions with a physiotherapist 2-3 times a week for 12 weeks. "The exercise therapy programme involves a warm up and various types of strength training. It is built up in stages that become more challenging as the patient improves and becomes stronger," explains Dr Jullum Kise. Each patient receives a personalized training programme, and learns to do the exercises under the supervision of a physiotherapist.

Menisci are crescent-shaped discs of cartilage on both sides of the knee joint. The meniscus is a shock absorber that distributes weight across the joint and at the same time stabilizes the joint when you walk or run. "We hope that the stronger muscles of the exercise therapy group may counteract osteoarthritis, a type of arthritis that often occurs in patients who have undergone surgery for a meniscus injury," says Dr Jullum Kise.