Beating plastic with plastic

The world’s annual consumption of plastic materials has increased from around 50 lakh tonnes in the 1950s to nearly 10 crore tonnes today. According to the Minister of State for Environment, Forest and Climate Change, 15,000 tonnes of plastic waste is generated in India every day, out of which 9,000 tonnes is collected and processed, while 6,000 tonnes is not collected. It was this problem faced by ordinary citizens that disturbed Ashwath Hegde, a Mangalore-born but now Qatar-based NRI entrepreneur.

In order to beat the plastic woes plaguing the world, Hegde, through his company EnviGreen, developed a biodegradable plastic bag made out of natural starch and vegetable oil derivatives — products that are non-toxic and can consumed by plants and animals. 

The bags can dissolve in room temperature water in 24 hours and dissolves in 15 seconds if placed in boiling water. The bags also take 180 days to biodegrade, which means people can discard them without worrying about the environment. However, the bags are still not available in India, although they are being distributed in Qatar and Abu Dhabi. The price of the bag is Rs 3. In contrast, a plastic bag is Rs 2, while a cloth bag is anything between Rs 20 and Rs 70.

Source: The better India, 5th Dec. 2016

Fastracking the implementation of biofuel program: Blending Ethanol with Diesel

After the success of green and white revolutions leading to self-sufficiency in food grains and milk production, the government is now looking at 'Krishna Kranti' (black revolution) to not only help India become self-sufficient in oil production but also provide a healthy environment to the people. 

Biodiesel can be produced from edible and non-edible oils (Jatropa curcas, mahua, karanjia, sunflower seeds and rapeseeds as a viable alternative to the conventional energy) through trans-esterification using ethanol or methanol. The properties of biodiesel are close to that of diesel fuel and in fact, it offers advantages in terms of emission control from diesel engines. In India the current assessments are based on non-edible oils for biodiesel production.  This green fuel has high octane and lubricity and readily mixes with diesel without any engine modification. And automobile manufacturers like Mahindra and Mahindra and Ashok Leyland have endorsed biodiesel as a fuel for their vehicles.

Source: The minister of state for petroleum and natural gas, Mr Dharmendra Pradhan informed the Rajya Sabha.

First biotech apple

The U.S. Department of Agriculture’s Animal and Plant Health Inspection Service (APHIS) approved two genetically engineered apple varieties designed to resist browning that have been developed by the Canadian company Okanagan Specialty Fruits Inc.The apples are said to be identical to the others but with an added advantage of resisting browning after being sliced. Okanagan plans to market the apples as Arctic Granny and Arctic Golden.

Source: Neal Carter, Okanagan President.

Scientists Regrow an Entire Rat Limb in the Lab

A team of regenerative scientists and surgeons at Massachusetts General Hospital successfully grew a semi-functional rat forelimb in the lab, employing a technique previously used to build bio-artificial organs. The same technique has been used to regenerate kidneys, ears and lungs in the lab. However, a limb is a bit trickier since it requires a wider variety of cells than these organs.

Scientists first used a special detergent to strip away every living cell except the protein-based collagen that gives vessels, tendons and muscles their shape. Then, researchers inserted muscle and vessel progenitor cells from a different rat.

In the future, these cells would be taken from the limb recipient, so that the final product would be biologically compatible with his or her body. To encourage growth, scientists placed the limb in a bioreactor that supplies nutrients, oxygen and electrical stimulation to the developing limb. It took about two to three weeks for it to finish growing, after which it was ready for testing. When scientists stimulated the forelimb with electricity, the paw clenched and unclenched, showing that the muscles were functional. When they attached it to anesthetized rats, blood flowed through the new limb, though it they didn’t test it for movement

Around the world, roughly 70 patients have undergone a hand transplant with favorable outcomes. However, the immune system tends to reject an unfamiliar hand, so these patients need to enroll in life-long immunosuppressive therapy. In the new approach, the big advantage is that the regrown cells are the recipient’s, so the risk of immune rejection is low.

The next challenge for scientists is to ensure nerves take root within a bio-artificial limb, which does occur in hand transplants. It isn’t clear if the same will occur in bio-artificial limbs.

Fig. 1: Scientists’ regrown rat limb

Fig. 2: Scientists’ rat limb grows in the bioreactor

Ref: Bernhard J. Jank et al., 2015, Biomaterials

doi:10.1016/j.biomaterials.2015.04.051

Scientists synthesise novel low-calorie fats

Scientists have developed novel low-calorie fats based on edible oils like sunflower that provide 5.2 K cals/g as against 9 K cals/g by the vegetable oils; they have shown promising health benefits in studies conducted in rats and rabbits. Ethyl behenic acid was incorporated into refined sunflower and soybean oils after about 25 per cent of fatty acids was removed. The fats have shown to lower serum, liver cholesterol and triglycerides in rats and reduce fat accumulation in arteries in rabbits. 

Source: Dr. R.B.N. Prasad, Head of Centre for Lipid Research, Indian Institute of Chemical Technology, Hyderabad.

Antibiotics in most honey brands

Scientists found high levels of six harmful antibiotics in 11 samples including  those made by Indian companies such as Dabur, Himalaya, Patanjali, Baidyanath and Khadi as well as by two foreign companies based in Switzerland and Australia except only the Indian Hitkari brand coming out clean.

The contamination begins when antibiotics are fed to bees to prevent disease which, promote growth and increase honey production to meet commercial targets. These substances could damage the blood, kidneys, liver, bones and teeth. More importantly, they create resistance in the body to prescribed antibiotics when you really do fall ill.

Dabur Honey, which has captured 75 per cent of the Indian market had the antibiotic Oxytetracycline at nine times the level that is permitted for exported honey. It also had significant amounts of two other drugs completely banned for use in honey. If the sample was placed for export to the United States or the European Union, it would have been rejected.

Nectaflor Natural Blossom Honey, made by Narimpex of Switzerland, had the largest number five of the six antibiotics that it was tested for, including the highest levels of ampicillin and erythromycin, both of which are not permitted for beekeeping in any country. It would be illegal to sell it even in Switzerland itself. Similarly, the Australian brand, Capilano Pure & Natural Honey, which is sold in 40 countries, violated standards set in its home country.

It is clear that foreign companies are taking advantage of the lack of regulations in India. After all, if our government does not care about the health of its people, why should these companies care? said CSE director, Sunita Narain.

Source: Sunita Narain, Director, Pollution Monitoring Laboratory, Centre for Science and Environment

Mapping the human brain without distortions

To study the fine structure of the brain including its connections between neurons and the synapses, scientists generally use electron microscopes. However, the brain tissue must first be fixed to prepare it for this high magnification imaging method. This process causes the brain to shrink and as a result, microscope images can be distorted showing neurons to be much closer than they actually are.

Researchers now solved the problem by using a technique that rapidly freezes the brain, preserving its true structure. The innovative method called "cryofixation" to prevent brain shrinkage during the preparation for electron microscopy. The method uses jets of liquid nitrogen to "snap-freeze" brain tissue down to -90 degrees celsius within milliseconds. The brain tissue here was mouse cerebral cortex. "The high-pressure 'cryofixation' is a very attractive method for brain imaging.

Source: Graham Knott, Natalya Korogod and Carl Petersen,  Swiss Federal Institute of Technology in Lausanne

Hippocampus of brain stores the time and place of memories

For the first time, scientists have seen evidence of where the brain records the time and place of real-life memories. The left anterior of the hippocampus aren't the totality of the memories, but just the broad picture of where and when it occurred and also it helped to "fine-tune" the time and place. "What we're picking up here is not the whole memory, but the basic gist the where and when of the experience," said Per Sederberg, senior author of the study and assistant professor of psychology at Ohio State."This could be viewed as the memory hub, where we have these general, large-scale representations of our experiences."

Ref: Dylan M. Nielson, 2015, PNAS

DOI:10.1073/pnas.1507104112

FDA nod for lung cancer screening device with a low dose CT

Detection of small lung nodules are critical in identifying lung cancer at its earliest stages when it is the most treatable and curable. Low dose CT lung cancer screening will inevitably save lives through earlier diagnosis and treatment for patients.

Source: GE Healthcare, 2015

Sleep calculator

Scientists have discovered how an animal's biological clock wakes it up in the morning and puts it to sleep at night. Brain circadian neurons that govern the daily sleep-wake cycle's timing. High sodium channel activity in these neurons during the day turn the cells on and ultimately awaken an animal, and high potassium channel activity at night turn them off, allowing the animal to sleep.

Ref: Matthieu Flourakis et al., 2015, Cell.

The molecular mechanisms of brassinosteroids in plant breeding

Fig: Growth defects of the model research plant thale cress (Arabidopsis thaliana) which are induced by missing of steroid hormones (left side). With the help of gibberelline production the defects could be repaired (right side). Credit: Brigitte Poppenberger / TUM

Two growth-promoting groups of substances, or phytohormones, the gibberellins and the brassinosteroids are used independently of each other for the breeding and production of crop plants. It is discovered that without brassinosteroids, a plant is unable to produce gibberellins.

Reg: Unterholzner, 2015, Plant Cell.

DOI: 10.1105/tpc.15.00433​

'Bionic' spinach plants can detect explosives

By embedding spinach leaves with carbon nanotubes, MIT engineers have transformed spinach plants into sensors that can detect explosives and wirelessly relay that information to a handheld device similar to a smartphone.

Credit: Christine Daniloff/MIT

 

This is one of the first demonstrations of engineering electronic systems into plants, an approach that the researchers call "plant nanobionics." In this case,  Spinach plants were designed to detect chemical compounds known as nitroaromatics, which are often used in landmines and other explosives. When one of these chemicals is present in the groundwater sampled naturally by the plant, carbon nanotubes embedded in the plant leaves emit a fluorescent signal that can be read with an infrared camera. The camera can be attached to a small computer similar to a smartphone, which then sends an email to the user.

Ref: Min Hao Wong et al., (2016), Nitroaromatic detection and infrared communication from wild-type plants using plant nanobionics, Nature materials.

Full Text
DOI: 10.1038/nmat4771

Lab-grown lungs successfully transplanted into mice

Transplanted HLO-scaffold constructs engrafted, grew and possessed airway-like structures.

Keyword: HLOs-Human Lung Organoids, PLG- poly(lactide-co-glycolide)  

Fig: (A) PLG scaffold are 5 mm in diameter with honeycomb-patterned architecture. (B) The majority of Di-O labeled 1d HLOs (green) remained at the surface of the scaffold with a few organoids descending toward the middle of the scaffold. Inset shows aerial view of the scaffold with 1d HLOs (green) scattered throughout. (C) 1d HLOs settled within the pores of the scaffold. Scale bar represents 100 µm. (D) PLG scaffolds were seeded with 1d HLOs and cultured for 5 to 7 days in vitro in media supplemented with FGF10. The HLO-laden scaffolds were then transplanted into the mouse epididymal fat pad and harvested at 8 weeks. (E) HLO-scaffold (dotted line) was placed in mouse epididymal fat pad. (F) Transplanted HLOs (tHLOs) ranged from 0.5 cm to 1.5 cm in length. (G) The average number airway-like structures that were NKX2.1+ ECAD+ out of all ECAD+ structures was 86.19% +/- 4.14% (N = 10, error bars represent SEM). (H) H&E of tHLOs showed airway-like structures (right two panels, low and high mag) and pockets of cartilage (left panel). Scale bar at low mag represents 200 µm and high mag 100 µm. (I) Airway-like structures outlined by ECAD (white) expressed the lung marker NKX2.1 (green). Scale bar represents 50 µm. (J–K) Both the epithelium (β-CAT, red) and mesenchyme expressed the human nuclear marker, HUNU (J, green) and the human mitochondrial marker huMITO (K, green). Scale bars represent 50 µm in J–K and 10 µm in high mag image in K.

DOI: http://dx.doi.org/10.7554/eLife.19732.003

Researchers at the University of Michigan have transplanted lab-grown mini lungs into immunosuppressed mice where the structures were able to survive, grow and mature. Respiratory diseases account for nearly 1 in 5 deaths worldwide, and lung cancer survival rates remain poor despite numerous therapeutic advances during the past 30 years. Now, the researchers attempted to transplant the miniature lungs into mice, an approach that has been widely adopted in the stem cell field. 

Researchers characterized the transplanted mini lungs as well-developed tissue that possessed a highly organized epithelial layer lining the lungs.

One drawback was that the alveolar cell types did not grow in the transplants. Still, several specialized lung cell types were present, including mucus-producing cells, multiciliated cells and stem cells found in the adult lung.

Ref:: Briana R Dye et al., (2016) A bioengineered niche promotes in vivo engraftment and maturation of pluripotent stem cell derived human lung organoids, eLIFE.

Full Text (PDF) 
DOI: 10.7554/eLife.19732