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Comment by Dr. Krishna Kumari Challa on August 8, 2021 at 11:18am

Organ transplant recipients significantly protected by COVID-19 vaccination

 In a Brief Communication, published July 29, 2021 in the journal Transplant Infectious Disease, a team of physician-scientists.

found that solid organ transplant recipients who were vaccinated experienced an almost 80 percent reduction in the incidence of symptomatic COVID-19 compared to unvaccinated counterparts during the same time. Persons who have received an organ transplant are considered to be at increased risk for COVID-19 and for a severe outcome because their immune systems are necessarily suppressed to ensure their transplants are successful and lasting.

These new findings offer strong evidence that getting vaccinated provides significant protection even to the immuno-suppressed people.

During the study period, there were 65 diagnosed cases of COVID-19 among the organ recipients: four among fully vaccinated individuals and 61 among the controls (two involving partially vaccinated individuals). There were no deaths among the breakthrough COVID-19 cases, but two among the 61 control cases.

it demonstrates real world clinical effectiveness of COVID-19 vaccination in a vulnerable population. Second, the effectiveness is better than expected, given that studies have found that only about half of solid organ transplant recipients develop detectable anti-spike antibodies after vaccination.

https://researchnews.cc/news/8207/Organ-transplant-recipients-signi...

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Comment by Dr. Krishna Kumari Challa on August 8, 2021 at 11:09am

 Machu Picchu older than previously thought

Machu Picchu, the famous 15th-century Inca site in southern Peru, is up to several decades older than previously thought, according to a new study .

Until now, estimates of Machu Picchu's antiquity and the length of its occupation were based on contradictory historical accounts written by Spaniards in the period following the Spanish conquest.

Researchers used  used accelerator mass spectrometry (AMS)—an advanced form of radiocarbon dating—to date human remains recovered during the early 20th century at the monumental complex and onetime country estate of Inca Emperor Pachacuti located on the eastern face of the Andes Mountains.

Their findings, published in the journal Antiquity, reveal that Machu Picchu was in use from about A.D. 1420 to A.D. 1530—ending around the time of the Spanish conquest—making the site at least 20 years older than the accepted historical record suggests and raising questions about our understanding of Inca chronology.

Historical sources dating from the Spanish invasion of the Inca Empire indicate that Pachacuti seized power in A.D. 1438 and subsequently conquered the lower Urubamba Valley where Machu Picchu is located. Based on those records, scholars have estimated that the site was built after A.D. 1440, and perhaps as late as A.D. 1450, depending on how long it took Pachacuti to subdue the region and construct the stone palace.

The AMS technique can date bones and teeth that contain even small amounts of organic material, expanding the pool of remains suitable for scientific analysis. For this study, the researchers used it to analyze human samples from 26 individuals that were recovered from four cemeteries at Machu Picchu in 1912 during excavations. The bones and teeth used in the analysis likely belonged to retainers, or attendants, who were assigned to the royal estate, the study states. The remains show little evidence of involvement in heavy physical labor, such as construction, meaning that they likely were from the period when the site functioned as a country palace, not when it was being built, the researchers said.

The AMS testing indicates that the historical timeline is inaccurate. This is the first study based on scientific evidence to provide an estimate for the founding of Machu Picchu and the length of its occupation, giving us a clearer picture of the site's origins and history.

The finding suggests that Pachacuti, whose reign set the Inca on the path to becoming pre-Columbian America's largest and most powerful empire, gained power and began his conquests decades earlier than textual sources indicate.

The results suggest that the discussion of the development of the Inca empire based primarily on colonial records needs revision. Modern radiocarbon methods provide a better foundation than the historical records for understanding Inca chronology.

https://www.cambridge.org/core/journals/antiquity/article/new-ams-d...

https://researchnews.cc/news/8221/Study--Machu-Picchu-older-than-ex...

Comment by Dr. Krishna Kumari Challa on August 7, 2021 at 1:36pm

Freeze-Dried Mouse Sperm Sent by Postcard Produces Baby Mice

Rather than relying on samples that need to be shipped in glass vials and on ice, researchers have developed a new method that allows mouse sperm to be sent easily at room temperature using standard mail delivery.

The new method, detailed in a study published today (August 5) in iScience, builds on the team’s previous work, which involved sending dehydrated mouse sperm stored in glass ampoules to the International Space Station to study how radiation affects mammalian cells. Drying the samples, the authors say, does away with the need for cold storage, and they’ve since refined the method further so that they can store sperm from thousands of different mouse strains in a single three-ring binder.

https://www.cell.com/iscience/fulltext/S2589-0042(21)00783-5?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS2589004221007835%3Fshowall%3Dtrue

https://www.the-scientist.com/news-opinion/freeze-dried-mouse-sperm...

Comment by Dr. Krishna Kumari Challa on August 7, 2021 at 12:06pm

Microbes engineered to convert sugar into a chemical found in tires

The future environmental footprint of the tire industry could be substantially shrunk thanks to a new ecofriendly way found by researchers that harnesses bacteria to make a chemical used in synthetic rubber.

Each year, factories around the world churn out more than 12 million metric tons of the organic chemical 1,3-butadiene, which is used in tires, adhesives, sealants and other plastic and rubber products. They produce it by an energy-intensive process that relies on petroleum, which contributes to climate change.

Scientists have tried for many years to create 1,3-butadiene from more environmentally friendly starting materials by using specially designed microbes. But no one had previously succeeded in transforming a simple sugar such as glucose into the chemical in one easy step.

Now, by engineering bacteria to convert glucose into 1,3-butadiene,  researchers have devised a sustainable approach to rubber and plastic production. They constructed a novel artificial metabolic pathway and produced 1,3-butadiene directly from a renewable source—glucose. They first engineered a bacterial enzyme that could convert a biological compound that can be developed from glucose into 1,3-butadiene . The researchers then modified a strain of the bacterium Escherichia coli to use this enzyme and produce the chemical. Since 1,3-butadiene is a gas at room temperature, it can be easily captured as the bacteria continue to divide and grow.

Yutaro Mori et al, Direct 1,3-butadiene biosynthesis in Escherichia coli via a tailored ferulic acid decarboxylase mutant, Nature Communications (2021). DOI: 10.1038/s41467-021-22504-6

https://phys.org/news/2021-08-microbes-sugar-chemical.html?utm_sour...

Comment by Dr. Krishna Kumari Challa on August 7, 2021 at 11:58am

Environmental impact of bottled water up to 3,500 times higher than tap water

The consumption of bottled water has been increasing sharply in recent years on a global scale. According to previous research, this trend can be partly explained by subjective factors like risk perception, taste, odor, lack of trust in public tap water quality and marketing by bottled water companies.

Environmental and health impacts are usually assessed separately due to the different methodologies applied and resulting outcomes. Environmental impacts can be estimated with a methodology called Life Cycle Assessment (LCA), while the consequences in human helath are estimated with an approach called Health Impact Assessment (HIA). This study has tried to overcome this methodological barrier for the first time by combining LCA and HIA in the same analysis.

The results of work done in Barcelona, Spain, showed that if the whole population of the city decided to shift to bottled water, the production required would take a toll of 1.43 species lost per year and cost of 83.9 million USD per year due to extraction of raw materials. This is approximately 1,400 times more impact in ecosystems and 3,500 times higher cost of resource extraction compared to the scenario where the whole population would shift to tap water.

The results results show that considering both the environmental and the health effects, tap water is a better option than bottled water, because bottled water generates a wider range of impacts.

Cristina M. Villanueva et al, Health and environmental impacts of drinking water choices in Barcelona, Spain: A modelling study, Science of The Total Environment (2021). DOI: 10.1016/j.scitotenv.2021.148884

https://phys.org/news/2021-08-environmental-impact-bottled-higher.h...

Comment by Dr. Krishna Kumari Challa on August 7, 2021 at 11:14am

Out of five promising antibodies that they isolated, the scientists decided to concentrate on one designated S2P6. Molecular structure analysis and functional studies showed that this human monoclonal antibody had impressive breadth: it was able to neutralize three different subgenera of beta-coronaviruses. The scientists observed that it did so by inhibiting the virus' ability to fuse with cell membranes.

The researchers went on to test if the S2P6 stem helix antibody could protect against SARS-CoV-2 by administering it to hamsters 24 hours before exposure. They found that this antibody reduced the viral load of SARS-CoV-2 by inhibiting entry of the virus and by enhancing additional anti-viral and virus-clearing cellular immune responses.

Studies of the plasma from pre-pandemic human samples, as well as from COVID-vaccinated and COVID-recovered individuals were also analyzed to see how frequently the stem-helix targeting antibodies appeared. They highest frequencies occurred in people who had recovered from COVID-19, then were later vaccinated. Overall, however, the data from this study shows that, while it does occur, it is relatively rare for SARS-CoV-2 to elicit plasma stem-helix antibody responses. The researchers hope that additional studies might reveal whether this is the case for antibodies that target other parts of the coronavirus fusion machinery or only for those that target the stem helix.

The researchers also looked at how the broadly reactive monoclonal antibodies studied in this project might have originated. Their findings suggest that they may have resulted from the priming of B memory cells through one of the common cold-inducing coronaviruses. Then the virus-specific B cells gained cross-reactivity through somatic mutations occurring during the body's immune response to a natural infection with another type of coronavirus.

The results from this study indicate that eliciting a sufficient quantity of stem helix antibodies through a standard vaccination development approach likely would be difficult. However, the researchers propose that recent computational protein-design advances for potential vaccine candidates against respiratory syncytial viruses and multiple influenza viruses might be adapted to try to induce broad beta coronavirus immunity and overcome the pan-coronavirus vaccine challenge.

Dora Pinto et al, Broad betacoronavirus neutralization by a stem helix–specific human antibody, Science (2021). DOI: 10.1126/science.abj3321

https://medicalxpress.com/news/2021-08-antibody-ideas-pan-coronavir...

Comment by Dr. Krishna Kumari Challa on August 7, 2021 at 11:13am

Antibody findings spark ideas for pan-coronavirus vaccine

Three epidemic or pandemic coronaviruses—SARS-CoV, MERS-CoV, & SARS-CoV-2—have spilled over from animals to cause deadly illness in humans in the past 20 years. Virus researchers are determined to discover a means to broadly safeguard people from the continuing threat of emerging coronaviruses.

Clues for creating such an overarching countermeasure might come from a rare type of human antibody that can neutralize several different coronaviruses. These antibodies have been detected in some people who have recovered from COVID-19.

A paper appearing Aug. 3 in the journal Science describes research on five such human monoclonal antibodies that can cross-react with a number of beta-coronaviruses. These antibodies target a structure, called stem helix, in the spike protein of these viruses. The spike protein is critical to the virus' ability to overtake host cells.

The stem helix in the spike protein has remained conserved during the evolution of certain coronaviruses. That means it is much less prone to genetic changes and is similar in various coronaviruses. These include those originating in bats that have become dangerous pathogens in people, and another subgenus that causes a serious human lung disease transmitted by dromedary camels, as well as a few other subgenera that cause simple common cold symptoms.

The researchers explain in their paper that they were interested in exploring antibodies that target highly conserved regions of the spike protein machinery that enable coronaviruses to fuse with the membrane of host cells. 

An antibody's ability to bind to the less mutable fusion machinery is what allows it to neutralize distantly related coronaviruses.

To find these sorts of antibodies, the researchers examined certain memory B cells from COVID-19 convalescent donors. Memory B cells are white blood cells that recognize and respond to pathogens that have tried to attack the body during a previous encounter.

part 1

Comment by Dr. Krishna Kumari Challa on August 6, 2021 at 10:51am

Using two CRISPR enzymes, a COVID diagnostic in only 20 minutes

Frequent, rapid testing for COVID-19 is critical to controlling the spread of outbreaks, especially as new, more transmissible variants emerge.

A research team is aiming to develop a diagnostic test that is much faster and easier to deploy than qRT-PCR. It has now combined two different types of CRISPR enzymes to create an assay that can detect small amounts of viral RNA in less than an hour.

While the new technique is not yet at the stage where it rivals the sensitivity of qRT-PCR, which can detect just a few copies of the virus per microliter of liquid, it is already able to pick up levels of viral RNA—about 30 copies per microliter—sufficient to be used to surveil the population and limit the spread of infections.

Liu, T.Y. et al. Accelerated RNA detection using tandem CRISPR nucleases. Nat Chem Biol (2021). DOI: 10.1038/s41589-021-00842-2

https://phys.org/news/2021-08-crispr-enzymes-covid-diagnostic-minut...

Comment by Dr. Krishna Kumari Challa on August 6, 2021 at 10:48am

When faces are partially covered, neither people nor algorithms are...

Artificial systems such as homecare robots or driver-assistance technology are becoming more common, and it's timely to investigate whether people or algorithms are better at reading emotions, particularly given the added challenge brought on by face coverings.

Comment by Dr. Krishna Kumari Challa on August 6, 2021 at 10:45am

Microwaving an ambulance. New technique could revolutionise how surfaces are disinfected
Microwave engineers, infectious disease specialists and polymer scientists have teamed up to create a novel microwave sterilization method that could revolutionize the way ambulances and hospitals are being disinfected.
At present, sterilization is done manually with conventional techniques that use chemicals. This can take around 30 to 40 minutes to disinfect a single ambulance.

During this time, the ambulance is out of action which puts increasing pressure on emergency services during busy times. The possibility of the new technique could drastically reduce the time it takes to get an ambulance safely back on the road to save lives.

In recent years, several other techniques have been proposed for disinfecting and sterilizing surfaces, ranging from hydrogen peroxide aerosols to UV irradiation and infrared radiation. However, these techniques have been shown to degrade surfaces over time, or to be harmful to humans if they are in close proximity. This has, so far, limited their long-term application.

In contrast, the new method works using electromagnetic waves, antennas, sensor beacons, and a liquid layer to rapidly heat-up and sterilize surfaces. Its automation means a person can easily operate the system from a safe distance rather than touching contaminated surfaces directly during cleaning.
The study used microwave beams emanating from antennas like those found in mobile smart phones and domestic Wi-Fi systems. The antennas allow the microwave radiation to be directed and focussed on locations where it is most needed.
K. Kossenas et al, A Methodology for Remote Microwave Sterilization Applicable to the Coronavirus and Other Pathogens using Retrodirective Antenna Arrays, IEEE Journal of Electromagnetics, RF and Microwaves in Medicine and Biology. DOI: 10.1109/JERM.2021.3077110
https://techxplore.com/news/2021-08-microwave-ambulance-technique-r...

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