Comment

Comment by Dr. Krishna Kumari Challa yesterday

Alternative to plastics: Seafood shells

We are facing plastic pollution like hell. 

Some scientists think it’s possible to tackle the  problem at once. Crustaceans’ hardy shells contain chitin, a material that, along with its derivative chitosan, offers many of plastic’s desirable properties and takes only weeks or months to biodegrade, rather than centuries.

The challenge is getting enough pure chitin and chitosan from the shells to make bio-based “plastic” in cost-effective ways. 

Chitin is one of the most abundant organic materials in the world, after cellulose, which gives woody plants their structure. In addition to crustaceans, chitin is found in insects, fish scales, mollusks and fungi. Like plastic, chitin is a polymer, a molecular chain made from repeating units. The building block in chitin, N-acetyl-D-glucosamine, is a sugar related to glucose. Chitin and chitosan are antibacterial, nontoxic and used in cosmetics, wound dressings and pool-water treatments, among other applications.

Only thing that stands in between using it and plastic is viable and green technology to obtain chitin. Right now scientists are trying various methods - using microbes to obtain chitin is one of them.

https://www.sciencenews.org/article/seafood-shells-chitin-plastic-f...

Comment by Dr. Krishna Kumari Challa on Thursday

Here is a heart-warming news:  In Science the world Still Trusts!  Despite pseudo-science's dirty dance! 
Roughly 7 in 10 people around the world say they trust scientists and want to learn more about science and health, an international survey shows

Among the survey's major findings:

• A greater share of younger people claim some knowledge of science than older people. "Worldwide, more than half the people aged 15–29 (53%) say they know 'some' or 'a lot' about science, compared to 40% of those aged 30–49 and 34% of those aged 50 and older," say the authors of the report.
• Overall, people around the world are interested in science, with 62% saying they would like to learn more about it.
• The understanding of concepts such as "science" and "scientist" vary around the world. For example, about 32% of people in Central Africa said "they understood none of the definitions presented to them or simply didn't know what science and scientist meant, the report shows. In contrast, about 2% in Northern America and most of Europe gave a similar answer.
• 18% of those interviewed have a "high" level of trust in scientists; 54% reported "medium" levels of trust, 14% have "low" trust and 13% said they don't know.
• About 70% of those surveyed say they feel that science benefits them. Only about 40% say they feel science benefits most people in their nation.

Do You Trust Science?

https://wellcome.ac.uk/reports/wellcome-global-monitor/2018

https://news.gallup.com/opinion/chairman/258329/trust-science.aspx

https://www.usnews.com/news/best-countries/articles/2019-06-19/the-...

Comment by Dr. Krishna Kumari Challa on June 18, 2019 at 7:06am

Clinical Trials Involving Fecal Transplants have their own risks

The US Food and Drug Administration issued a safety alert for fecal transplant procedures after two immune-compromised patients contracted drug-resistant infections, according to a statement from the agency’s website. The patients received transplants from the same donor, and one of the patients died. As a result, the agency plans to suspend clinical trials involving the procedure.

Fecal matter transplants (FMT) are not yet officially approved by the US Food and Drug Administration (FDA). “While we support this area of scientific discovery, it’s important to note that FMT does not come without risk,” Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research, says in a brief statement on the agency’s website. Marks does not state how many clinical trials will be affected, but says it was “not just a few.”
The FDA warns that fecal matter should be tested for drug-resistant bacteria. Today’s safety communication underscores the importance of why new therapies are thoroughly studied to ensure the benefits of taking them outweigh the risks to patients, and they will continue to aggressively monitor clinical trials to ensure patients are protected when safety concerns arise.

Comment by Dr. Krishna Kumari Challa on May 29, 2019 at 7:52am

Severe air pollution can cause birth defects, deaths

Researchers from Texas A&M University have determined that harmful particulate matter in the atmosphere can produce birth defects and even fatalities during pregnancy using the animal model.

The team of researchers from Texas A&M's Colleges of Agriculture and Life Sciences and Geosciences, the Texas A&M Health Science Center, and colleagues from the University of California-San Diego has had their findings published in the current issue of PNAS (Proceedings of the National Academy of Sciences).

Using female rats, the team examined the adverse health effects of exposure to fine particulate matter consisting of ammonium sulfate commonly found in many locations around the world. 

During winter months in China and India, where severe haze events frequently occur, fine particulate matter levels were especially high at several hundred micrograms per cubic meter, the team concluded.

Air pollution is a century-old problem for much of the world. According to the World Health Organization, 9 out of 10 people worldwide breathe air containing high level of pollutants, and 1 of every 9 global deaths can be attributed to exposure to air pollution, totaling over 7 million premature deaths a year.

Sulfate is mainly produced from coal burning, which is a major energy source for much of the world in both developed and developing countries. Ammonium is derived from ammonia, which is produced from agricultural, automobile, and animal emissions.

The results also show that prenatal exposure to air pollution may not dispose offspring to obesity in adulthood. Previous studies have shown such pollution to impair metabolic and immune systems in animal offspring, but this team's study shows definitive proof of decreased fetal survival rates, and also shortened gestation rates that can result in smaller body weight, in addition to damage to brains, hearts and other organs in the adult rat models.

Comment by Dr. Krishna Kumari Challa on May 25, 2019 at 9:07am

How Bacteria Become Drug-Resistant While Exposed to Antibiotics

Escherichia coli is capable of synthesizing drug-resistant proteins even in the presence of antibiotics designed to cripple cell growth. That’s the finding by a group of French researchers reporting on May 23 in Science. They also discovered how the bacteria manage this feat: a well-conserved membrane pump shuttles antibiotics out of the cell—just long enough to buy the cells time to receive DNA from neighbor cells that codes for a drug-resistant protein. 

Many bacterial membranes are known to harbor a multidrug efflux pump known as AcrAB-TolC, which is capable of shuttling a wide range of antibiotics out of cells. 

They found that the mutants, although they received the plasmid bearing the genetic code for TetA from neighboring cells, weren’t capable of synthesizing TetA protein. Without the functional efflux pump, the mutants can’t shuttle the tetracycline out of the cells. As levels of the antibiotic surged inside the cells, they could no longer make proteins or grow. 

When functional, the AcrAB-TolC pump buys the bacteria time by keeping antibiotic concentrations just low enough for the cells to synthesize the resistance proteins encoded in the plasmid DNA, according to the researchers. Ultimately, bacteria can become resistant while still under the influence of antibiotics. 

S. Nolivos et al., “Role of AcrAB-TolC multidrug efflux pump in drug-resistance acquisition by plasmid transfer,” Science, doi:10.1126/science.aax6620, 2019. 

Comment by Dr. Krishna Kumari Challa on May 23, 2019 at 8:56am

Measles erases the immune system’s memory

Beyond the rash, the infection makes it harder for the body to remember and attack other invaders

The most iconic thing about measles is the rash — red, livid splotches that make infection painfully visible.

But that rash, and even the fever, coughing and watery, sore eyes, are all distractions from the virus’s real harm — an all-out attack on the immune system.

Measles silently wipes clean the immune system’s memory of past infections. In this way, the virus can cast a long and dangerous shadow for months, or even years, scientists are finding. The resulting “immune amnesia” leaves people vulnerable to other viruses and bacteria that cause pneumonia, ear infections and diarrhea. It really puts you at increased susceptibility for everything else. And that has big consequences, recent studies show.

Wherever you introduce measles vaccination, you always reduce childhood mortality. Always. The shot prevents deaths, and more than just those caused by measles. By shielding the immune system against one virus’s attack, the vaccine may create a kind of protective halo that keeps other pathogens at bay, some researchers suspect.

M. Rosen. Kids who have had measles are at higher risk of fatal infections. Science News. Vol. 187, May 30, 2015, p. 10.

Comment by Dr. Krishna Kumari Challa on May 23, 2019 at 8:37am

Hypertension found in children exposed to flower pesticides

In Ecuador, roses for Mother's Day sold around the world is major export crop, but pesticides used to grow and treat those flowers may be affecting health of children living nearby

In a study published online May 21, 2019 in the journal Environmental Research, researchers at University of California San Diego School of Medicine found higher blood pressure and pesticide exposures in children associated with a heightened pesticide spraying period around the Mother's Day flower harvest. This study involved boys and girls living near flower crops in Ecuador.

Researchers assessed 313 boys and girls, ages 4 to 9, residing in floricultural communities in Ecuador. The children were examined up to 100 days after the Mother's Day harvest. The analyses are part of a long-term study of environmental pollutants and child development in Ecuador.

Researchers  observed that children examined sooner after the Mother's Day harvest had higher pesticide exposures and higher systolic and diastolic blood pressures compared to children examined later. In addition, children who were examined within 81 days after the harvest were three times more likely to have hypertension than children examined between 91 and 100 days.

There is some evidence that insecticides, such as organophosphates, can increase blood pressure. Organophosphates and several other classes of insecticides and fungicides are commonly used to treat flowers for pests before export.

In a previous study, the same people had reported that children examined sooner after the harvest displayed lower performances in tasks of attention, self-control, visuospatial processing and sensorimotor than children examined later.

"These new findings build upon a growing number of studies describing that pesticide spray seasons may be affecting the development of children living near agricultural spray sites. They highlight the importance of reducing the exposures to pesticides of children and families living near agriculture."

https://www.sciencedirect.com/science/article/pii/S0013935119302889

Comment by Dr. Krishna Kumari Challa on May 19, 2019 at 10:34am

Researchers from England’s Medical Research Council Laboratory of Molecular Biology have successfully created E. coli bacteria with entirely human-made DNA, marking a milestone in the burgeoning field of synthetic biology and paving the way for future innovation built on so-called “designer” bacteria.
According to a new study published in the journal Nature, the synthetic genome is by far the largest of its kind. The product of a two-year research campaign, the redesigned DNA consists of four million segments—four times more than the previous record holder. Perhaps most impressively, the bacteria contain just 61 codons, as opposed to the 64 found in nearly all living creatures. Despite this seeming disparity, the synthetic bacteria appear to function much like normal E. coli. The main differences are a slower growth rate and longer length.
https://www.nature.com/articles/s41586-019-1192-5

Comment by Dr. Krishna Kumari Challa on May 9, 2019 at 9:10am

Teenager recovers from near death in world-first GM virus treatment

Bacteria-killing viruses known as phages offer hope of solution to antibiotic resistance

A British teenager has made a remarkable recovery after being the first patient in the world to be given a genetically engineered virus to treat a drug-resistant infection.

Isabelle Holdaway, 17, nearly died after a lung transplant left her with an intractable infection that could not be cleared with antibiotics. After a nine-month stay at Great Ormond Street hospital, she returned to her home in Kent for palliative care, but recovered after her consultant teamed up with a US laboratory to develop the experimental therapy.

The scientists behind the breakthrough have said bacteria-killing viruses, known as phages, have the potential to be used as an alternative treatment to counter the antibiotic resistance.

Isabelle has cystic fibrosis, a genetic disease that results in frequent infections clogging up the lungs with mucus. By summer 2017, her lungs had less than a third of their normal function and she had been plagued by two stubborn bacterial strains for eight years. She and her doctors decided a double lung transplant was the best option, even though it meant her existing infections could spread.

After the transplant, this fear became a reality: a bacterial strain similar to TB took hold, colonising her surgical wound, then her liver, until eventually pockets of bacteria known as nodules began pushing through the skin on her arms, legs and buttocks. Phages work by infecting bacteria cells and killing them, but they are very specific in which infections they can target. Scientists identified dozens of phages known to infect bacterial relatives of the patients’ strains, and tested thousands of combinations of them in petri dishes to see which wiped out the patients’ bacteria.Finally, they found a phage that could hit the strain that infected one of the teenagers. Each experiment took a week because the bacteria grow slowly. Shortly after Isabelle was sent home on a palliative care plan, Hatfull’s lab identified a phage that wiped out the infection, and another two phages that could infect it but not kill it efficiently. By removing a single gene, they were able to increase the efficiency of these two phages, making a cocktail that they believed could kill the infection. A combination was used to avoid the possibility of the infection becoming resistant to the phage. In June 2018, Isabelle returned to Great Ormond Street and after some safety tests, was given the cocktail twice daily via an intravenous drip and on her skin. Six weeks later a liver scan revealed the infection had essentially disappeared. And there were no side effects!

https://www.nature.com/articles/s41591-019-0437-z

Comment by Dr. Krishna Kumari Challa on May 8, 2019 at 9:54am

Rice husks can remove microcystin toxins from water

Scientists at The University of Toledo have discovered that rice husks can effectively remove microcystin from water, a finding that could have far-reaching implications for communities along the Great Lakes and across the developing world.

An abundant and inexpensive agricultural byproduct, rice husks have been investigated as a water purification solution in the past. However, this is the first time they have been shown to remove microcystin, the toxin released by harmful algal blooms.

The results of the study were recently published in the journal Science of the Total Environment.

Researchers found the rice husks removed more than 95 percent of microcystin MC-LR -- the most common type found in Lake Erie -- in concentrations of up to 596 parts-per-billion (ppb). Even in concentrations approaching 3,000 ppb, more than 70 percent of the MC-LR was removed, and other types of MCs were removed as well.

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