Climate Change Corrodes Shark Skin

We’ve heard it before that sharks have repeatedly survived mass extinctions… surely, they should be able to survive the one our planet seems to currently be undergoing, right? Although they have been around since the dinosaurs, it seems sharks are facing their most fearsome foe yet: climate change.

After destroying their habitats, overfishing, and hunting them, humans have caused shark numbers to decline at a staggering rate. In a study published in the journal https://www.nature.com/articles/s41598-019-54795-7">Scientific Reports, researchers show that prolonged exposure to acidified water corrodes shark’s skin. Shark skin is not like ours; it’s made up of thousands of little scales, called dermal denticles, that have a makeup like teeth. While some can be seen by the naked eye, the impact acidic water has on dermal denticles can only be seen via electron microscope. But how acidic are we talking about? Currently our oceans average a pH of 8.1, which is apparently 25 percent more acidic than in pre-industrial times. For this research, the scientists kept puffadder shysharks (Haploblepharus edwardsii) in tanks of 7.3 pH water. Why this specific number? According to one estimate, ocean water could be this acidic by the year 2300.

“It's probably not going to be an average for the ocean, even in 2300,” Luiz Rocha, curator of fishes at the California Academy of Sciences, told Wired. “Unless instead of slowing down, we continue racking up the amount of greenhouse gases that we're dumping in the atmosphere. If it drops to 7.3, we are doomed. Everything is going to fall apart, not just sharks.”

Climate change will have an enormously varied impact on the world’s oceans. Overall, some changes that can be expected include increased warming, a decrease in pH levels, decreases in dissolved oxygen (leading to more ‘dead spots’ of very low oxygen), and changes in salinity. For highly mobile animals such as sharks, it’s harder to study how these changes will impact them. Already we are seeing shifts in their swimming behavior and changes to migratory patterns, food availability and altered brain development are all predicted to occur if things continue the way they are.

Scanning electron micrographs show that the denticles of puffadder shysharks kept in pH 7.3 water for nine weeks (right) were substantially more degraded than those of sharks kept in normal ocean water (left).

Scanning electron micrographs show that the denticles of puffadder shysharks kept in pH 7.3 water ... [+]

J. DZIERGWA ET AL/SCIENTIFIC REPORTS 2019

But not all sharks are migratory. Some, like this slender benthic catshark, stay in one spot. Puffadder shysharks are endemic to the coast of South Africa, preferring the cold waters here to scavenge on crustaceans, polychaetes and small fishes. Camouflaged due to their sandy color and reddish saddles with dark and white spots, they tend to be seen as pests by local fishermen due to them eating bait off their hooks. While seen as a nuisance to some, they were a great study species since they have such a restricted range! The experiments, done in a lab, were carried out for nine weeks where after the researchers looked at the puffadder’s dermal denticles. On average, a quarter of the denticles on the sharks in acidic water were damaged, compared to 9.2 percent on the controls. “Damaged denticles may impact their ability to hunt or escape,” study co-author Lutz Auerswald, biologist at Stellenbosch University in South Africa, told Wired. “In addition, since sharks’ teeth are from the same material, corrosion may impact hunting and feeding.”

Ocean acidification is a major, but often less understood, concern for sharks. In fact, all sharks and their relatives (rays, skates, and chimaeras) have teeth and denticles made from this same material that seems to be vulnerable in increasingly acidic water. While done in a lab and only on one species, the results are still troubling. Our oceans may not get this acidic in the near future, but it’s just another hurdle for these animals to overcome. Currently they face more pressing threats such as overfishing and bycatch, habitat destruction, and even shark finning. But climate change shouldn’t be ignored. “The rate of climate change is very fast compared to previous changes,” says Auerswald. “Most likely, shark species will feel the impact differently and some may not be able to cope, whereas others may have the potential to adapt.”

Coral reefs with higher microbial diversity are much healthier, study finds

A collaborative study that compared seawater from 25 reefs in Cuba and the U.S. Florida Keys, which varied in human impact and protection, found that those with higher microbial diversity and lower concentrations of nutrients and organic carbon (primarily caused by human activities) were markedly healthier.

Researchers sampled seawater from each site and measured nutrients as well as a variety of other parameters that offer insight into the microbial community. They found a notable difference between the heavily protected offshore reefs in Cuba and the more impacted nearshore ones in the Florida Keys.

They found that exploring the connection between microorganisms and the health of coral reefs can be difficult due to the lack of unspoiled reef systems around the world.

“Human impacts such as overfishing and pollution lead to changes in reef structure,” says WHOI graduate student Laura Weber, lead author of the paper. “Removal of algae grazers such as herbivorous fish and sea urchins leads to increases in macroalgae, which then leads to increased organic carbon, contributing to the degradation of coral reefs.”

The study outlines how offshore and highly-protected reefs are healthier than nearshore reefs with less protection from human impacts. Additionally, reefs with lower nutrient runoff and carbon from industrial activities are markedly healthier.

“Cuba does not have large-scale industrialised agriculture or extensive development along most of its coastline,” says Patricia González-Díaz, Director of CIM-UH and co-author of the study. “So there is not a lot of nutrient run-off and sedimentation flowing on to the reefs.”

Additionally, the reefs of Jardines de la Reina, the largest protected area in the Caribbean, may be further buffered from impacts by the mangroves and seagrass meadows that lie between the island of Cuba and the reef system of Jardines de la Reina. Here, researchers found low concentrations of nutrients, and a high abundance of Prochlorococcus—a photosynthetic bacterium that thrives in low nutrient waters. More accessible and heavily-impacted areas in Florida Keys both contained higher organic carbon and nitrogen concentrations.

The work suggests that protection from a variety of human impacts does play a significant role in maintaining microbial diversity. The hope is that these findings could aid resource managers in deciding how best to protect and restore Caribbean coral reefs in the face of habitat and climate-based change.

To read the full paper, Microbial signatures of protected and impacted Northern Caribbean reefs: changes from Cuba to the Florida Keys,click here. Co-authors of the paper include colleagues from CIM-UH, Universidad Nacional Autónoma de México, Phillip and Patricia Frost Museum of Science, Mote Marine Laboratory, and the University of California, Santa Barbara.

Photograph by Amy Apprill, courtesy of Woods Hole Oceanographic Institution.

Japan creates method for effective cancer detection

Tokyo, Nov 25 (Prensa Latina) A clinical method with 99 percent effectiveness in detecting the presence of 13 types of cancer through a blood test was created in Japan, a local scientific spokesperson reported today.

According to the source, this method can diagnose gastric, esophageal, pulmonary, hepatic, biliary tract, pancreas, intestinal, ovarian, prostate, bladder, breast, sarcomas and glioma cancers in less than two hours.

The technology was devised by the Toshiba corporation, the National Cancer Center Research Institute (NCCRI) and the Tokyo Medical University.

The detection tool analyzes micromolecules of ribonucleic acid (or micro-RNA) and that the objective of this diagnostic system is to carry out further research in 2020 to then implement this scientific novelty.

The new breakthrough should allow, once in practice, early treatment for this illness and favor survival rates and patient quality of life.

How climate change affects us physically, emotionally and socially

As a cold snap grips the Northeast, you are likely to reach for your coat, hat, and gloves before leaving the house in the morning. An anti-pollution mask with a 5-layer HEPA filter and built-in fan is typically not on your checklist.

This, however, is one of the items that residents of New Delhi, India need as they battle a smog crisis, which for the past 2 weeks has endangered the respiratory health of millions. Last week, the government ordered schools closed for a second time as a result of severely poor air quality. SAFAR, India’s pollution monitoring agency, advised everyone to close all their windows and avoid going outside. If people had to go outdoors, SAFAR recommended they wear N-95 or P-100 respirators. These are the kind of masks used on construction sites.

India is not alone in its struggle to breathe. According to the World Health Organization, nine out of 10 people worldwide are exposed to air containing high levels of pollutants. A staggering 7 million people die each year as a result of dangerous outdoor and household air quality. The statistics also hit close to home. Based on the 2018 American Lung Association’s “State of the Air” report, Philadelphia ranks as the 12th worst city in the country in terms of its year-round air pollution.

How we reached this environmental emergency is fairly clear. Climate scientists from around the world agree that greenhouse gases released by burning fossil fuels have made our planet warmer. Heat waves and stagnant air worsen air pollution, along with the industrial emissions themselves. The United Nations’ 2018 IPCC report on climate change concluded that global warming is likely to reach 1.5 degrees C between 2030 and 2052, impacting health, livelihoods, water supply, human security, and economic growth. Children, older adults, and other vulnerable populations will bear the brunt of it, especially those living in poverty.

The climate crisis does not just affect us physically, but emotionally and socially as well. It can disrupt our most basic sense of safety, taking away routines and choices that are critical for wellness. Where before, we might have taken for granted living in a hospitable environment, our relationship with nature seems more threatened than ever by anxiety and mistrust.

Emerging data supports the connection between climate change and increasing emotional distress. A 2018 study of 2 million people living in the U.S. found that exposure to more extreme weather was associated with worse mental health. A 1 degree C increase in temperature over five years coincided with a 2-percentage point increase in mental health issues.

Some studies have focused on specific weather events. Their results link depression and post-traumatic stress disorder symptoms to hurricanes and floods. The risk of suicide increases with heat waves and drought. Other consequences of climate change may include sleep disturbance, negative mood expressed on social media, and diminished cognitive performance among children. Experts also fear that social upheaval and intergroup conflict due to weather-related migration will further contribute to poor mental health outcomes.

In recent years, alarm over the earth’s vital signs has sounded throughout the world’s political, scientific, and medical communities. Political will and corporate change have not always followed. In fact, we have seen regression in the form of President Trump announcing his intentions of pulling out of the Paris Climate Accord, which would make the United States stand apart from nearly 200 other nations committed to reducing greenhouse gas emissions.

In spite of this looming policy barrier, there are steps that individuals, corporations, and countries can take to address climate change.

A study of the world’s largest and most environmentally friendly corporations, published this July, found that top-performers adopt proactive, detail-oriented strategies to improve sustainable practices, as opposed to simply managing risk. This pre-emptive stance includes exceeding regulatory standards, being vocal about their efforts to help the environment, and a willingness to devote resources to ease the consequences of global warming.

At a personal level, you should not underestimate the positive impact you could have by reducing your carbon footprint. According to 2017 data from the University of Oxford’s Global Change Lab, each person in the U.S. produces an average of 16 tons of CO2 a year. It takes approximately 229 trees to absorb that amount of carbon dioxide. Conservation.org offers a free carbon footprint calculator to spark ideas around lifestyle changes that could help offset these emissions. Areas include transportation, diet, and energy use.

Any action to support the environment can boost a sense of well-being and contribute to your carbon offset. The University of Michigan’s Center for Sustainable Systems offers some suggestions:

  • Eat local, vegetarian, or organic foods
  • Buy energy-efficient appliances, especially refrigerators, which are responsible for large amounts of energy consumption
  • Walk, bike, carpool, and use mass transit whenever possible
  • Turn off electronics when not in use
  • Recycle and buy products with minimal packaging

Environmental awareness, altruistic intent, and future-orientation are key. As French author Antoine de Saint Exupéry once wrote, “As for the future, it is not a question of foreseeing it, but of making it possible.”

Scott Glassman is a clinical assistant professor and associate director of the MS program in mental health counseling at Philadelphia College of Osteopathic Medicine.

Heart disease and cancer risk may be linked

Heart attack survivors may have an increased risk of developing cancer compared to people without cardiovascular disease, according to research to be presented at the American Heart Association's Scientific Sessions 2019 -- November 16-18 in Philadelphia.

People with more risk factors for cardiovascular diseases were also at higher risk for developing cancer compared to people with lower cardiovascular disease risk.

"It's a double whammy. Heart disease and cancer are the two leading causes of death in the United States. We now recognize that they are intimately linked. This tells us that we, as physicians, should be aggressive in trying to reduce cardiovascular risk factors not only to prevent heart disease, but also to consider cancer risk at the same time," said study lead author Emily Lau, M.D., a cardiology fellow at Massachusetts General Hospital in Boston.

Using data from the Framingham Heart Study, researchers evaluated data from 12,712 participants (average age 51) without cardiovascular disease or cancer at the start of the study. The American Heart Association/American College of Cardiology's Atherosclerotic Cardiovascular Disease (ASCVD) Risk Estimator and biomarkers (substances released into the bloodstream when the heart is damaged) were used to measure cardiovascular risk. The ASCVD risk estimator is a tool to help predict a person's risk of developing heart disease within ten years.

During the study period of nearly 15 years, 1,670 cancer cases occurred (19% gastrointestinal; 18% breast; 16% prostate; 11% lung). The researchers found:

  • Cardiovascular risk factors, including age, sex, high blood pressure and smoking status, were independently associated with cancer.
  • Those with a 10-year ASCVD risk of 20% or higher were more than three times as likely as those with 10-year ASCVD risk of 5% or lower to develop any type of cancer.
  • People who developed cardiovascular disease (a heart attack, heart failure or atrial fibrillation) during the study period had more than a sevenfold increased risk for subsequent cancer compared to those who did not experience any cardiac event.
  • Similarly, those with high levels of BNP, a biomarker frequently elevated in heart failure, were more likely to get cancer during the 15-year follow-up period than participants with low levels of BNP.

"I think it's interesting that BNP, a cardiac marker linked to heart failure risk, was associated with the risk of cancer in the future. Currently we use BNP to determine if a person has developed heart failure from chemotherapy drugs used to treat cancer," said Tochi M. Okwuosa, D.O., Vice Chair, American Heart Association Council on Clinical Cardiology and Genomics and Precision Medicine Cardio-Oncology Subcommittee and associate professor at Rush University, Chicago. "This is the first study that has shown that BNP that's elevated at baseline is associated with the future risk of cancer."

"Cancer and cardiovascular disease share many of the same risk factors, such as tobacco use, poor nutrition and lack of physical activity. The next step is to identify the biological mechanisms driving the link between cardiovascular disease and cancer," said Lau.

Many of the same lifestyle habits that reduce the risk of heart disease also reduce the risk of some kinds of cancer; so following the American Heart Association Life's Simple 7 may help prevent both diseases. Life's Simple Seven includes recommendations to eat a healthy diet (more fruits and vegetables, whole grains and lean protein), be physically active; avoid all tobacco/nicotine products and attain and maintain a healthy body weight, cholesterol, glucose and blood pressure," said Eduardo Sanchez, M.D., M.P.H., chief medical officer for prevention for the American Heart Association.

Lau said this was an observational study, so it doesn't prove cause and effect, but it does shed light on the connection between heart disease and cancer.


Story Source:

Materials provided by American Heart Association. Note: Content may be edited for style and length.


One avocado a day helps lower 'bad' cholesterol for heart healthy benefits

Move over, apples -- new research from Penn State suggests that eating one avocado a day may help keep "bad cholesterol" at bay.

According to the researchers, bad cholesterol can refer to both oxidized low-density lipoprotein (LDL) and small, dense LDL particles.

In a randomized, controlled feeding study, the researchers found that eating one avocado a day was associated with lower levels of LDL (specifically small, dense LDL particles) and oxidized LDL in adults with overweight or obesity.

"We were able to show that when people incorporated one avocado a day into their diet, they had fewer small, dense LDL particles than before the diet," said Penny Kris-Etherton, distinguished professor of nutrition, who added that small, dense LDL particles are particularly harmful for promoting plaque buildup in the arteries. "Consequently, people should consider adding avocados to their diet in a healthy way, like on whole-wheat toast or as a veggie dip."

Specifically, the study found that avocados helped reduce LDL particles that had been oxidized. Similar to the way oxygen can damage food -- like a cut apple turning brown -- the researchers said oxidation is also bad for the human body.

"A lot of research points to oxidation being the basis for conditions like cancer and heart disease," Kris-Etherton said. "We know that when LDL particles become oxidized, that starts a chain reaction that can promote atherosclerosis, which is the build-up of plaque in the artery wall. Oxidation is not good, so if you can help protect the body through the foods that you eat, that could be very beneficial."

While previous research demonstrated that avocados could help lower LDL cholesterol, Kris-Etherton and her colleagues were curious about whether avocados could also help lower oxidized LDL particles.

The researchers recruited 45 adult participants with overweight or obesity for the study. All participants followed a two-week "run-in" diet at the beginning of the study. This diet mimicked an average American diet and allowed all participants to begin the study on similar nutritional "footing."

Next, each participant completed five weeks of three different treatment diets in a randomized order. Diets included a low-fat diet, a moderate-fat diet, and a moderate-fat diet that included one avocado a day. The moderate-fat diet without avocados were supplemented with extra healthy fats to match the amount of monounsaturated fatty acids that would be obtained from the avocados.

After five weeks on the avocado diet, participants had significantly lower levels of oxidized LDL cholesterol than before the study began or after completing the low- and moderate-fat diets. Participants also had higher levels of lutein, an antioxidant, after the avocado diet.

Kris-Etherton said there was specifically a reduction in small, dense LDL cholesterol particles that had become oxidized.

"When you think about bad cholesterol, it comes packaged in LDL particles, which vary in size," Kris-Etherton said. "All LDL is bad, but small, dense LDL is particularly bad. A key finding was that people on the avocado diet had fewer oxidized LDL particles. They also had more lutein, which may be the bioactive that's protecting the LDL from being oxidized."

The researchers added that because the moderate-fat diet without avocados included the same monounsaturated fatty acids found in avocados, it is likely that the fruit has additional bioactives that contributed to the benefits of the avocado diet.

Kris-Etherton said that while the results of the study -- published in the Journal of Nutrition -- are promising, there is still more research to be done.

"Nutrition research on avocados is a relatively new area of study, so I think we're at the tip of the iceberg for learning about their health benefits," Kris-Etherton said. "Avocados are really high in healthy fats, carotenoids -- which are important for eye health -- and other nutrients. They are such a nutrient-dense package, and I think we're just beginning to learn about how they can improve health."

Soft drinks found to be the crucial link between obesity and tooth wear

A new study published today in the journal Clinical Oral Investigations, has found that sugar-sweetened acidic drinks, such as soft drinks, is the common factor between obesity and tooth wear among adults.

Scientists from King's College London found that being overweight or obese was undoubtedly associated with having tooth wear. Significantly, they also found that the increased consumption of sugary soft drinks may be a leading cause of the erosion of tooth enamel and dentine in obese patients.

Drawing on data from the National Health and Nutrition Examination Survey 2003-2004, they analysed a representative sample of survey participants of 3,541 patients in the United States. Patient BMI and the level of tooth wear were the exposure and outcome measurements in the analysis. The intake of sugar-sweetened acidic drinks was recorded through two non-consecutive 24-hour recall interviews where the patients were asked to provide details of diet intake across these two days.

"It is the acidic nature of some drinks such as carbonated drinks and acidic fruit juices that leads to tooth wear," said lead author Dr Saoirse O'Toole from King's College London.

Tooth wear is ranked as the third most important dental condition, after cavities and gum disease and the consumption of acidic food and drink is a leading cause of this. Obese patients also have other risk factors such as increased likelihood of gastric reflux disease (heartburn) which was controlled for in this study.

"This is an important message for obese patients who are consuming calories through acidic sugar sweetened drinks. These drinks may be doing damage to their body and their teeth. There is also an important message for dentists. We should be asking our patients who are obese and have tooth wear what calories they are drinking as this may be having an effect on their full bodies -- not just their teeth," Dr O'Toole added.

Previous research from King's has found that tooth wear affects up to 30% of European adults. It is the premature wearing of teeth due to the softening of the dental enamel from dietary or gastric acids, combined with wear and tear. It occurs when the outer layer (enamel) of the tooth slowly dissolves. This can lead to changes in the shape or appearance of teeth, and they can become sensitive when eating or drinking cold food and drinks. At its worst, the tooth structure can gradually wear away. Severe Erosive Tooth Wear reduces quality of life and can mean complex and costly procedures, costing up to £30,000 per patient. Tooth wear is preventable and changes to consumption habits can help stop people from getting it or making it worse.

 

Mysterious newly discovered virus DEFIES EVOLUTION, current scientific understanding

Scientists in Japan have discovered a new type of virus which could redefine our understanding of viruses and how they propagate and spread, all while sifting through pig feces.

Unlike most other organisms which fall under the definition of ‘life,’ viruses have no cells: they are merely a particle of genetic material (RNA or DNA) within a protein shield that is capable of infecting a cell before replicating. 

While sifting through pig feces, as you do, researchers from the Tokyo University of Agriculture and Technology (TUAT) came across a virus which defied everything we thought we knew about the infectious agents.

“The recombinant virus we found in this study has no structural proteins,” says virologist Tetsuya Mizutani from TUAT about the strain of a type of enterovirus G (EV-G) the team encountered. “This means the recombinant virus cannot make a viral particle.”

Also on rt.com Olympic fever? Tourists may be unaware Japan IMPORTED Ebola in preparation for 2020 games....

This particular "defective variant" of the virus the team uncovered lacked even the limited protein container found in other viruses, and instead merely had "flanking genes" in its structure. This means that the virus would not be able to invade a host on its own, which begs the question: how on Earth does it survive?

The team suggests that this virus, and any potential copycats it might have out there in the natural world, might exploit other viruses to do the heavy lifting of both transporting it around and helping it to infect host targets. 

A lot more research is required to fully understand what is going on here, but the discovery could upend our understanding of viruses in general while blasting open new doors of research into combatting some of humanity's greatest biological threats. 

“We may be facing an entirely new system of viral evolution,” Mizutani says.

We are wondering how this new virus came to be, how it infects cells or how it develops a viral particle. Our future work will be on solving this mystery of viral evolution.

Also on rt.com DNA ‘echoes’ of ancient viruses could help to kill cancer, new research finds

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