Researchers discover green tea could reduce antibiotic resistance

September 26, 2019

Washington D.C., Sept 23: Green is already known for its antioxidant properties but did you know that it can prove beneficial in getting rid of antibiotic-resistant bacteria.

Yes! Researchers have discovered that a natural antioxidant commonly found in green tea can help eliminate antibiotic-resistant bacteria.

The findings were published in the Journal of Medical Microbiology in which the researchers found that epigallocatechin (EGCG) can restore the activity of aztreonam, an antibiotic commonly used to treat infections caused by the bacterial pathogen -- Pseudomonas aeruginosa.

P. aeruginosa is associated with serious respiratory tract and bloodstream infections and has become resistant to many major classes of antibiotics over the years.

Currently, a combination of antibiotics is used to fight P. aeruginosa. However, these infections are becoming increasingly difficult to treat, as resistance to last-line antibiotics is being observed.

To assess the synergy of EGCG and aztreonam, researchers conducted in vitro tests to analyse how they interacted with the bacterial pathogen individually and in combination.

The team found that the combination of aztreonam and EGCG was significantly more effective at reducing P. aeruginosa numbers than either agent alone.

This synergistic activity was also confirmed in vivo using Galleria mellonella (Greater Wax Moth larvae), with survival rates being significantly higher in those treated with the combination than those treated with EGCG or aztreonam alone. Furthermore, minimal to no toxicity was observed in human skin cells and in Galleria mellonella larvae.

Researchers believe that in P. aeruginosa, EGCG may facilitate increased uptake of aztreonam by increasing permeability in the bacteria. Another potential mechanism is EGCG's interference with a biochemical pathway linked to antibiotic susceptibility.

"Antimicrobial resistance (AMR) is a serious threat to global public health. Without effective antibiotics, the success of medical treatments will be compromised. Natural products such as EGCG, used in combination with currently licenced antibiotics, maybe a way of improving their effectiveness and clinically useful lifespan," said lead author Dr Jonathan Betts, Senior Research Fellow in the School of Veterinary Medicine at the University of Surrey.

"The World Health Organisation has listed antibiotic-resistant Pseudomonas aeruginosa as a critical threat to human health. We have shown that we can successfully eliminate such threats with the use of natural products, in combination with antibiotics already in use," said Professor Roberto La Ragione, Head of the Department of Pathology and Infectious Diseases in the School of Veterinary Medicine at the University of Surrey.


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News Network
September 19,2020


New Delhi, Sept 19: Scientists examined the effectiveness of common household fabrics used in homemade masks in blocking droplets generated by coughing and sneezing, and have found that they are considerably protective even as a single layer.

While earlier studies have focussed on the transfer of tiny, nanoscale aerosol particles through masks, the researchers from the University of Illinois at Urbana-Champaign in the US said speaking, coughing, and sneezing generates larger droplets -- about one millimeter in diameter -- that can carry virus particles.

They said the larger droplets pose a problem as they can squeeze through the pores of some fabrics if they have sufficient momentum, and break into smaller droplets and become airborne.

In the study, published in the journal Extreme Mechanics Letters, the scientists filled the nozzle of an inhaler with distilled water seeded with easy-to-find ultrasmall fluorescent particles -- which happens to be the size of a novel coronavirus particle.

The inhaler forced the water through the nozzle when puffed, and generated high-momentum droplets that collected on a plastic dish placed in front of the inhaler, the study noted.

The researchers repeated this process with the various materials placed over the collection dishes to test their ability to block the particles.

"We count the number of nanoparticles landing on the dish using a high-resolution confocal microscope. We can then use the ratio of the number collected with and without the fabric to give us a measure of droplet-blocking efficiency," said study co-author Taher Saif.

However, the scientists said for an individual to feel compelled to wear a mask, the material must not only be able to block the droplets, but also be comfortable and breathable.

"A mask made out of a low-breathability fabric is not only uncomfortable, but can also result in leakage as the exhaled air is forced out around contours of a face, defeating the purpose of the mask and providing a false sense of protection," Saif said.

"Our goal is to show that many common fabrics exploit the trade-off between breathability and efficiency of blocking droplets -- large and small," he added.

The scientists tested the breathability and droplet-blocking ability of 11 common household fabrics, including new and used garments, quilted cloths, bedsheets and dishcloth material, using a medical mask as a benchmark.

They then characterised the fabrics in terms of their construction, fiber content, weight, thread count, porosity and water-absorption rate.

Their analyses revealed that droplets leave the inhaler at about 17 metres per second (mps) while those released by speaking, coughing and sneezing have velocities within the range of 10 to 40 (mps).

"We found that all of the fabrics tested are considerably effective at blocking the 100 nanometer particles carried by high-velocity droplets similar to those that may be released by speaking, coughing and sneezing, even as a single layer," Saif said.

"With two or three layers, even the more permeable fabrics, such as T-shirt cloth, achieve droplet-blocking efficiency that is similar to that of a medical mask, while still maintaining comparable or better breathability," he added.

The researchers believe the new experimental platform may offer a way to test fabrics for their blocking efficiency against the small and larger droplets that are released as people breathe, or cough.


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Dr Nandini Sankaranarayanan
September 28,2020


The booming market for digital devices has flooded us with plenty of options to choose from, for various purposes ranging from entertainment to educational and professional uses. Mobile phones, tablets, laptops and video gaming devices have come to play an important part in our daily lives, however, they have also impacted our lifestyles, resulting in some new types of health issues. One of the most common results of the improper/excessive use of digital devices has been an unpleasant eye condition called ‘digital eye strain’.

What is digital eye strain?

Digital eye strain results from spending long hours on digital devices. Common symptoms include watering, itching, stinging or burning sensation, with tired and achy eyes. Sometimes there may be blurring of vision and headache after intense use of digital devices.

Until recently, this condition was commonly seen among IT professionals. But lately, we see many children as young as 4-5 years old being brought to the Ophthalmologist, with digital eye strain.

What has changed for these children? With the shifting of schools to online learning due to the current pandemic, children now spend longer durations with gadgets. It is important that we teach our children on ways to use digital devices without straining their eyes.

Dos and Don’ts for children while using digital devices for long durations

1. Make sure that they sit in well-lit rooms.

2. The device must have a large screen. Avoid small screens like mobile phones or tablets.

3. The screen should be about 40-50 cm from the eyes with a tilt of 10-20 degree and just below the eye level for comfortable viewing.

4. Encourage them to take a break from the screen every 20 minutes or so, and look at some far off object about 20 feet away for 20 seconds before resuming work on the screen. This is called 20-20-20 rule which gives much needed relief for the muscles of the eyes.

5. Use break times to rest and relax the eye. Avoid using digital devices during breaks.

6. Encourage them to blink more often. The blink rate of eyes comes down to about 3-4 from a normal blink rate of 12-15, as one works on the screen for long periods. This hampers the spreading of tear-film, causing dry patches and discomfort in the eyes.

7. For any online extracurricular activities, it’s a good idea to cast it on television which has a bigger screen and can be viewed from far off distance without strain on the eyes.

8. Avoid screen-related activities about 1-2 hours prior to bedtime.

When to consult a doctor

Following the tips outlined above will go a long way in avoiding digital eye strain, especially in young eyes. In spite of all these precautions, it’s not unusual for the child to complain of redness, watering, itching, blurring, headache and in severe cases, even squinting of eyes.

In any of the aforementioned cases, immediate consultation must be sought from a qualified Specialist Ophthalmologist who will thoroughly evaluate their eyes and give appropriate treatment. It’s not unusual for the ophthalmologist to detect refractive problems or squint in eyes which the child and parents may not be aware of.

The only connect for our children with the outside world in these challenging times is through these digital devices! Let us not chide them for using these devices, but teach them the proper way of utilizing them for their benefit!


Dr Nandini Sankaranarayanan is a Specialist Ophthalmologist at Thumbay Medical and Dental Specialty Centre, Sharjah.


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September 29,2020

New Delhi, Sept 29: ICMR scientists have flagged presence of another Chinese virus called 'Cat Que Virus', which has a "potential" to cause disease in India, even as it grapples with the Covidpandemic. CQV can cause febrile illnesses, meningitis and paediatric encephalitis in humans.

According to the seven researchers at the Indian Council of Medical Research's National Institute of Virology in Pune, the presence of Cat Que Virus in Culex mosquitoes and pigs has been reported in China and Vietnam. They added that due to the spread of similar species of the Culex mosquitoes in India, there is a need to understand the replication kinetics of this virus.

The researchers said that the presence in Culex mosquitoes in China and pigs in Vietnam suggested susceptibility of Asian countries to CQV.

The scientists discovered antibodies for the tropical virus in two out of the 883 human serum samples tested across states. It indicates that these two people were infected with the virus at some point of time. It was not found in any of the human at the time of study.

"Anti-CQV IgG antibody positivity in human serum samples tested and the replication capability of CQV in mosquitoes indicated a possible disease causing potential of CQV in Indian scenario. Screening of more human and swine serum samples using these assays is required as a proactive measure for understanding prevalence of this neglected tropical virus,a the research published in Indian Journal of Medical Research in June stated.

In Indian context, "data showed that mosquitoes such as Ae. aegypti, Cx. quinquefasciatus and Cx. Tritaeniorhynchus were susceptible to CQV. Thus, mosquitoes were found to be a potential vector for CQV transmission to mammalian hosts", a scientist stated.

According to the apex research body, domestic pigs are the primary mammalian host of CQV and antibodies against the virus have been reported in swine reared locally in China, indicating that CQV has formed a natural cycle in local areas.


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