Knowledge Update

​New York, June 28 (IANS) A single oral dose of a drug that is already being used to treat a type of blood disorder could also improve our memory, suggests new research.

The researchers found that single dose of the common, inexpensive and safe chemical called methylene blue results in an increased response in brain areas that control short-term memory and attention.

Methylene blue is used to treat methemoglobinemia, a blood disorder in which oxygen is unable to release effectively to body tissues, and as a surgical stain.

"Although the memory-enhancing effects of methylene blue were shown in rodents in the 1970s, the underlying neuronal changes in the brain responsible for memory improvement and the effects of methylene blue on short-term memory and sustained-attention tasks have not been investigated," said study author Timothy Duong from University of Texas Health Science Center at San Antonio, Texas. 

"Our team decided to conduct the first multi-modal MRI study of methylene blue in humans," Duong noted.

Twenty-six healthy participants, between the ages of 22 and 62, were enrolled in a double-blinded, randomised, placebo-controlled clinical trial to measure the effects of methylene blue on the human brain during working-memory and sustained-attention tasks. 

The participants underwent functional MRI (fMRI) before and one hour after low-dose methylene blue or placebo administration to evaluate the potential effects of the compound on cerebrovascular reactivity during tasks. 

Mean cerebral blood flow was measured pre- and post-intervention.

The results showed methylene blue increased response in the bilateral insular cortex -- an area deep within the brain associated with emotional responses -- during a task that measured reaction time to a visual stimulus. 

The functional MRI results also showed an increased response during short-term memory tasks involving the brain's prefrontal cortex, which controls processing of memories, the parietal lobe, primarily associated with the processing of sensory information, and the occipital cortex, the visual processing centre of the brain. 

In addition, methylene blue was associated with a seven percent increase in correct responses during memory retrieval.

The study was published online in the journal Radiology.

The findings suggest that methylene blue can regulate certain brain networks related to sustained attention and short-term memory after a single oral low dose​

​New York, June 28 (IANS) Researchers including one of Indian-origin have created a new computer model that shows how tiny slits in the spleen prevent diseased red blood cells from re-entering the bloodstream.

Their model provides a new tool for studying the spleen's role in controlling diseases that affect the shape of red blood cells, such as malaria and sickle cell anaemia, and can be used to develop new diagnostics and therapeutics for a variety of acute and chronic diseases.

"The computational and analytical models from this work, along with a variety of experimental observations, point to a more detailed picture of how the physiology of human spleen likely influences several key geometrical characteristics of red blood cells," said Subra Suresh, President, Carnegie Mellon University in Pittsburgh, Pennsylvania, US.

The findings were published in the journal Proceedings of the National Academy of Sciences.

"They also offer better understanding of how the circulatory bottleneck for the red blood cell in the spleen could affect a variety of acute and chronic disease states arising from hereditary disorders, human cancers and infectious diseases, with implications for therapeutic interventions and drug efficacy assays." 

The spleen is like the water treatment plant for the body's bloodstream. It prevents pathogens from reaching the bloodstream and filters out old and misshapen red blood cells.

In order to "see" how the interendothelial slits regulate red blood cell circulation, the researchers created a computer simulation based on dissipative particle dynamics, a modeling method developed and refined for biological cells in partnership with Brown University Professor George Karniadakis. 

Their model allowed them to determine the range of cell sizes and shapes that could fit through the slits. 

The range closely mirrored the range of sizes and shapes for healthy red blood cells, indicating that only healthy cells should be able to pass through the slits.

In addition to giving researchers a better picture of how the spleen functions, the findings provide new insights into drug treatments. 

A class of drugs currently in development for treating malaria alters the shape of red blood cells infected with malaria, theoretically preventing them from passing through the interendothelial slit. 

The researchers' results also could explain why artemisinin-based anti-malarial drugs, which stiffen healthy and malaria-infected red blood cells, could lead to severe anaemia, the study said.​

​Beijing, June 26 (IANS) China will send its second orbiting space lab Tiangong-2 into space in mid September, said a senior official with the country's manned space programme.

The Shenzhou-11 manned spacecraft will be launched in mid September and its re-entry module will return in November, said Wu Ping, deputy director of the manned space engineering office, at a press conference on Saturday after the successful launch of the Long March-7, a new generation carrier rocket, at Wenchang, Hainan province.

As part of the country's space lab programme, the Shenzhou-11 spacecraft will carry two astronauts on board and dock with Tiangong-2.

The two astronauts have been chosen and currently under intense training, Wu said.

The Tiangong-2 and Shenzhou-11 will be carried by Long March-2F carrier rocket, she said.

In April 2017, the country's first cargo spaceship, Tianzhou-1, will be launched and carried by the Long March-7, Wu said.

"With the improvement of the rocket's technological performance, the Long March-7 will step by step replace the current carrier rockets and become the main carrier for space launches," she added.​

Kuala Lumpur, June 26 (IANS) Dried sewage sludge could be recycled by adding it to cement to make concrete, researchers in Malaysia have discovered.

Disposing sludge left over from treating sewage water is a major challenge for wastewater plants.

Meanwhile, the construction sector seeks economic and ecological cement replacement materials in order to meet an increasing demand for concrete.

Researchers from Universiti Teknologi MARA investigated the potential to replace various quantities of cement with processed sewage sludge to create a concrete mixture.

The researchers first produced domestic waste sludge powder (DWSP). They dried and burnt wet sludge cake to remove moisture, and then ground and sieved the dried sludge cake to make the sludge powder.

Using varying proportions of the powder, ranging from three-fifteen per cent, the researchers mixed the material with cement to produce normal strength and two higher strength grades of concrete.

They then compared the domestic waste sludge powder concrete mixture of each proportion with normal concrete in terms of their compressive strength, water absorption, water permeability and permeability to salt.

Overall, the researchers found that while domestic waste sludge powder has a potential role in the manufacture of concrete, the performance of the concrete blends tends to decline with increasing concentrations of the powder.

The findings were published in the Pertanika Journal of Science and Technology.

"Overall, there is potential for using DWSP as a partial cement replacement," the researchers said.

"However, more detailed research should be conducted to yield better quality powder," they added.​

​London, June 27 (IANS) Space-based detector can spot at least two gravitational waves -- ripples in space-time -- each year caused by collisions between supermassive black holes, revealing the initial mass of the seeds from which the first black holes grew 13 billion years ago.

A space-based instrument called the Evolved Laser Interferometer Space Antenna (eLISA) detector is set to be launched in 2034.

As eLISA will be in space - and will be at least 250,000 times larger than detectors on Earth - it should be able to detect the much lower frequency gravitational waves caused by collisions between supermassive black holes that are up to a million times the mass of our sun.

Scientists led by Durham University's Institute for Computational Cosmology ran the huge cosmological simulations that can be used to predict the rate at which gravitational waves caused by collisions between the monster black holes might be detected.

The study combined simulations from the EAGLE project - which aims to create a realistic simulation of the known Universe inside a computer - with a model to calculate gravitational wave signals.

“Understanding more about gravitational waves means that we can study the universe in an entirely different way. These waves are caused by massive collisions between objects with a mass far greater than our Sun," said lead author Jaime Salcido, PhD student in Durham University.

"By combining the detection of gravitational waves with simulations we could ultimately work out when and how the first seeds of supermassive black holes formed,” Salcido added.

In February, the international LIGO and Virgo collaborations announced that they had detected gravitational waves for the first time using ground-based instruments and in June reported a second detection.

Current theories suggest that the seeds of these black holes were the result of either the growth and collapse of the first generation of stars in the Universe; collisions between stars in dense stellar clusters; or the direct collapse of extremely massive stars in the early Universe.

As each of these theories predicts different initial masses for the seeds of supermassive black hole seeds, the collisions would produce different gravitational wave signals.

This means that the potential detections by eLISA could help pinpoint the mechanism that helped create supermassive black holes and when in the history of the Universe they formed.

“Black holes are fundamental to galaxy formation and are thought to sit at the centre of most galaxies, including our very own Milky Way,” noted co-author professor Richard Bower.

“Our research has shown how space-based detectors will provide new insights into the nature of supermassive black holes,” he added.

Gravitational waves were first predicted 100 years ago by Albert Einstein as part of his Theory of General Relativity.

The research was set to be presented at the Royal Astronomical Society's national astronomy meeting in Nottingham on Monday.​

Washington, June 24 (IANS) Researchers have developed a new technology that aims to make the Advanced Laser Interferometer Gravitational-Wave Observatory (LIGO) even more sensitive to gravitational waves -- faint ripples in space-time.

The team from Massachusetts Institute of Technology (MIT) and Australian National University report on improvements to what is called a squeezed vacuum source. 

Although not part of the original Advanced LIGO design, injecting the new squeezed vacuum source into the LIGO detector could help double its sensitivity. 

This will allow detection of gravitational waves that are far weaker or that originate from farther away than is possible now.

“There are many processes in the universe that are inherently dark; they don't give off light of any colour,” said Nergis Mavalvala from MIT Kavli Institute for Astrophysics and Space Research. 

"Since many of those processes involve gravity, we want to observe the universe using gravity as a messenger,” Mavalvala said in a paper that appeared in the Optica. 

Scientists at Advanced LIGO announced the first-ever observation of gravitational waves earlier this year -- a century after Albert Einstein predicted their existence in his general theory of relativity. 

Studying gravitational waves can reveal important information about cataclysmic astrophysical events involving black holes and neutron stars.

Researchers from the California Institute of Technology and MIT conceived, built, and operate identical Advanced LIGO detectors in Livingston, Louisiana and Hanford, Washington. 

Each observatory uses a 2.5-mile-long optical device known as an interferometer to detect gravitational waves coming from distant events, such as the collision of two black holes detected last year.

The researchers are planning to add their new squeezed vacuum source to Advanced LIGO in the next year or so. 

Once implemented, it will improve the sensitivity of the gravitational detectors, particularly at the higher frequencies important for understanding the composition of neutron stars. 

These extremely dense stars contain the mass of the sun, which has a radius of 700,000 km, within just a 10-km diameter.​

New York, June 24 (IANS) A team of researchers has developed the first scalable method to identify different subtypes of neurons in the human brain.

The research lays the groundwork for "mapping" the gene activity in the human brain and could help provide a better understanding of brain functions and disorders, including Alzheimer's, Parkinson's, schizophrenia and depression.

By isolating and analysing individual human brain cells, researchers identified 16 neuronal subtypes in the cerebral cortex -- the brain's outer layer of neural tissue responsible for cognitive functions including memory, attention and decision making. 

"We are providing a unified framework to look at and compare individual neurons, which can help us find out how many unique types of neurons exist," said Kun Zhang, bioengineering professor at University of California-San Diego.

Researchers can use these different neuronal subtypes to build what Zhang calls a "reference map" of the human brain -- a foundation to understand the differences between a healthy brain and a diseased brain.

"In the future, patients with brain disorders or abnormalities could be diagnosed and treated based on how they differ from the reference map. This is analogous to what's being done with the reference human genome map," Zhang noted.

The team, led by University of California-San Diego, The Scripps Research Institute (TSRI) and US-based life science research company Illumina, published their findings in the journal Science.​

​New York, June 25 (IANS) The US space agency is planning to drive the Curiosity Rover towards water sites on the Martian surface to further investigate the long, seasonally changing dark streaks briny water in the hope of finding evidence of life.

"It is not as simple as driving a rover to a potential site and taking a scoop of soil," said Jim Green, NASA's director of planetary science.

"Not only are these on steep slopes, we need to ensure that planetary protection concerns are met. In other words, how can we search for evidence of life without contaminating the sites with bugs from Earth?," he added in a NASA statement.

After approval of mission extension, NASA's Curiosity Mars rover would continue to climb to higher and younger strata on Mount Sharp -- mountain in Gale crater -- to investigate how the ancient, water-rich environments found till now persisted as the red planet dried out. 

A stroll on these destinations would help the one-tonne rover closer to locations where dark streaks are present on slopes and allow it to capture images of the potential water sites from miles away and see if any are the seasonally changing type.

NASA's High-Resolution Imaging Science Experiment (HiRISE) camera on the Mars Reconnaissance Orbiter (MRO) has observed many features of interest. They appear as dark lines that appear to ebb and flow over time. 

"Planetary scientists think these gullies or recurring slope lineae (RSLs) may appear seasonally as a form of briny water at or near the surface of the Red Planet under warmer conditions," NASA said.

NASA is also worried about how close could the rover safely get to an RSL? 

"In terms of coming much closer, we need to understand well in advance the potential for Earth organisms to come off the rover and that will tell us how far away the rover should stay," said Catharine Conley, NASA's planetary protection officer.

The darkish streaks are considered "special regions" on Mars, where extra precautions must be taken to prevent contamination because of the suspected presence of liquid water, considered a prerequisite for life.​

​London, June 25 (IANS) Researchers have found that high-tech scans can spare patients suffering from cancer of the lymphatic system of the serious side effects of chemotherapy as well as predict the outcome of treatment.

In the study, using positron emission tomography (PET) -- a type of imaging test that uses a tiny amount of radioactive glucose to look for disease in the body -- the doctors scanned more than 1,200 patients with advanced Hodgkin lymphoma after they had been given two cycles of standard chemotherapy.

Hodgkin lymphoma is a cancer that starts in white blood cells called lymphocytes. 

“Personalising treatment based on how well it works is a major development for patients with Hodgkin lymphoma and sets a new standard of care,” said Peter Johnson, Professor at University of Southampton in Britain.

The patients were divided into two groups - the first group that continued chemotherapy with bleomycin -- an important drug used to treat Hodgkin lymphoma -- and the second group had chemotherapy without the drug.

Bleomycin comes with potential risks of severely affecting the lungs leading to serious breathing problems.

The results showed that patients who stopped having bleomycin had the same survival rates as those who continued it. But, importantly, they were spared of the side effects.

"The good news is that the majority of people diagnosed with Hodgkin lymphoma can be cured - in this trial more than 95 per cent of patients are alive after three years,” Johnson added.

Three year progression-free survival was seen in patients who underwent chemotherapy without bleomycin was 84.4 per cent.

Further, 85.7 per cent patients who underwent chemotherapy with bleomycin had three-year progression-free survival

For patients with a good outlook stopping bleomycin did not have any negative effects.

However, patients who had a more resistant form of the disease were given more intense chemotherapy treatment, the study said.

“Getting to know the patients that have a more difficult form of the disease means we can select those who need stronger chemotherapy, while sparing everyone else the severe side effects such as infertility,” Johnson said in the study published in the New England Journal of Medicine.

“This approach, along with a reduction in the need for radiotherapy, should substantially reduce damage to healthy tissues and the risk of second cancers caused by treatments,” he concluded.​