📰 No more use and throw?
•Post the release of the film, Padman , there has been a lot of discussion on the need for proper menstrual products for women in India. But as important as this issue is, there are problems with the disposal of such over-the-counter personal hygiene products. Their contribution to immense generation of waste and pollution cannot be ignored.
•The National Family Health Survey (NFHS) 2015-16 found that about 57.6% of Indian women use disposable napkins. If a woman uses two pads per day during each period (approximately five days in a month), then the total number of pads used each year (by this group) would be 44.9 billion pads per year. This is a mountain of sanitary waste. There is now a move to convince women to move to biodegradable products that will help tackle the problem of disposable products that contain plastic.
•However, there are two issues with biodegradable products which merit discussion. While some argue that though napkins used by healthy women (that is, not sourced from hospitals and clinics) may be soiled with blood and bodily fluids, they are pathogen-free. Therefore, all such napkins are safe to compost along with other wet waste. Any plastics in them can then be removed from the generated compost and treated as non-recyclable plastic waste.
•The counterargument is that composting soiled napkins would nevertheless require human contact which amounts to undignified labour. People are needed to handle this waste while pre-treating it (by mixing napkins with microbes, dry leaves and shredding). Further, biodegradable napkins which contain bleached cellulose and sheets made from corn starch would take much longer — up to six months — to compost.
•This leaves incineration as the only other option to treat soiled napkins. But this process poses a fresh set of questions. In Bengaluru, for instance, those living in apartment blocks with more than 50 flats are required to arrange for the transportation and treatment of sanitary waste by certified incinerators. In the case of apartment blocks with fewer than 50 flats and individual houses, the local corporation is responsible for the collection and transportation of this waste to incinerators. However, given the poor state of monitoring, the effectiveness of this policy is questionable. The cost of incineration is also extremely high because of the cost of transportation. It works out to around Rs. 25-35 a kg, sometimes with a requirement of a minimum order of 100 kg a month.
Using sustainable products
•The real problem in menstrual hygiene is that napkins, biodegradable or not, will result in the generation of waste. With the lack of adequate waste disposal machinery in India, the surmounting burden of disposing of pads may be too much to bear. In such a situation, we may have to move away from a culture of use-and-throw products altogether and adopt sustainable products that can be used, washed and reused.
•There is growing acceptance for cloth-based reusable napkins. This can have a positive impact in terms of reducing the sheer volume of menstrual waste being generated each year. Another alternative is to use silicone cups that can be reused for at least 10 years and which require only washing with soap and water, with occasional sanitisation using warm water. Menstrual cups are available online and in pharmacies for as low as Rs. 300. Even without considering the high costs of sanitary waste incineration — if pads were available at Rs. 2 a pad (thanks to Padman ) — a woman would have to spend at least Rs. 2,400 over 10 years which is almost 10 times the cost of a menstrual cup.
•These alternative sustainable products offer a way of averting burgeoning menstrual product waste. There are several companies that manufacture and promote sustainable products. If you are a woman, it is time to think about using sustainable products. Be your own superhero.
📰 Nepal for ties based on mutual respect
Movement of goods should not be stopped in modern era, says PM Oli
•Placing barriers on movement of goods and people is incompatible with the modern era, said Nepal Prime Minister K.P. Sharma Oli on Saturday, in an indirect reference to the economic blockade of his country, which lasted for several months during 2015-16.
•Strongly pitching for an interconnected Asian continent, the visiting leader said Kathmandu has embarked on a path of social and economic development after 2017 multi-level elections and urged greater connectivity, trade and electricity cooperation with India.
•“We need to ensure that bilateral as well as regional connectivity and transit arrangements run smoothly without any interruption at all times. Recourse to obstacles in the movement of goods, services and people should not have any place in today’s interconnected world and in interconnected neighbourhood ,” said Mr. Oli at a civic reception hosted by the India Foundation here.
•This was the first time that a Nepali Prime Minister has even obliquely referred to the blockade at a public meeting in Delhi. Minister of State for External Affairs General (Rtd.) V. K. Singh, speaking after Mr. Oli, said the visiting leader had made a set of ‘candid’ observations.
•The blockade, which lasted many months, took place during Mr. Oli’s last tenure as Prime Minister. Nepali leaders had then blamed India for supporting the Madhesi groups from the Nepal’s plains that had imposed the punitive measure seeking changes in the 2015 Constitution. India had maintained that the blockade was an internal matter and had to be resolved through dialogue among various parties.
📰 ‘Demolish illegal resorts in elephant corridor’
Amicus curiae highlights how laws were violated for exploitation of forest area
•All hotels and resorts constructed in brazen violation of forest, building and panchayat Acts in the country’s most critical elephant corridor in The Nilgiris should be sealed and demolished, according to a note submitted by A.D.N Rao, amicus curiae, in the Supreme Court.
•Mr. Rao stated that the construction and running of the hotels and resorts was a “commercial activity undertaken for profit in the elephant corridor in brazen violation of about half-a-dozen laws.” This was in a forest area and in gross violation of the orders of the Supreme Court. He urged that the orders of the Madras High Court dated April 7, 2011 may be affirmed.
Reducing conflict
•The note was submitted to the court on writ petition (civil) No. 897 of 1996 in the matter of A. Rangarajan and Others vs Union of India and others, raising the important issue of protecting elephants and their corridors to reduce man-elephant conflict.
•The Amicus Curiae requested the Supreme Court to consider issuing some directions to restore the most critical elephant corridor in the country.
•All hotels, lodges and resorts were operating after amalgamation of plots of more than one 250 sq. m. or of slightly less area to circumvent the law (TN Panchayat Building Rules 1997), he said.
•The Act prohibits diversion of forestland for non-forest use without the approval of the Central government.
📰 CSMCRI uses seaweed to remove lead, chromium and dyes from wastewater
The adsorbed iron does not get leached out even at low pH conditions
•Removing toxic metals such as lead and chromium and certain dyes from industrial wastewater much more effectively has become possible thanks to the work of Indian researchers. Researchers at CSIR-Central Salt & Marine Chemicals Research Institute, Bhavanagar, Gujarat have synthesised a graphene–iron sulphide nanocomposite to remove these toxic materials from wastewater.
•The nanocomposite was prepared by mixing dried green seaweed Ulva fasciatawith iron chloride and heated to 150 degree C for 30 minutes to remove all moisture and then heated at 800 degree C for three hours in inert condition. Hydrogen sulphide gas, which is produced when seaweed is heated, reacts with iron to form iron sulphide.
•“The graphene nanocomposite functionalised with iron sulphide facilitates the adsorption of heavy metals and dyes,” says Dr. Ramavatar Meena from CSMCRI, one of the corresponding authors of a paper published in the Journal of Hazardous Materials. The nanocomposite was found to have very high adsorption capacity for lead (645 mg/g) at neutral pH. “The amount of lead adsorbed is the highest ever reported for any biomass derived carbon material. Lead adsorption was irreversible even at low pH as the interaction of lead with the composite is very strong,” he says.
•The nanocomposite with adsorbed lead was found suitable for removing chromium (100 mg/g) too. However, the ability to adsorb chromium was dependent on the presence of adsorbed lead. “Lead has high affinity for chromate and dichromate leading to the formation of lead chromate or lead dichromate,” Dr. Meena says.
Complete recovery
•Unlike lead which cannot be recovered from the nanocomposite, it was possible to completely recover the adsorbed chromium by dispersing the material in basic solution (pH around 12) for a few seconds. Thus, it was possible to reuse the nanocomposite twice to remove chromium without any drop in efficiency.
Effective against dyes
•The nanocomposite showed very good ability to adsorb different dyes used in textile industry — methylene blue, methyl orange, crystal violet and congo red. Highest adsorption capacity of 970 mg/g was seen in the case of congo red followed by crystal violet (909 mg/g), methyl orange (664 mg/g), and methylene blue (402 mg/g). The adsorption capacity was tested for each dye individually and also in a mixed solution. “The material was highly efficient to fully remove all the dyes present in water,” he says.
•“The adsorption capacity remained more or less the same whether the solution contained single dye or a mixture. The adsorption capacity did not vary much even in the presence of high concentration of salts,” Dr. Meena says. Most importantly, the nanocomposite could be reused up to eight times to remove the dyes.
•The researchers tested the ability of the material to remove the toxic reactive black-5 dye in a continuous flow condition by coating a filter paper with a thin layer of the composite. “All the dye was removed and the water became colourless within five minutes of treatment. The surface area of the material was high as it was coated on the filter paper and so it was able to remove the dye quickly. When the composite is used as such it will take about three hours to completely remove the dye,” he says.
•The preliminary results using filter paper coated with the material highlights the potential of the composite to be used in combination with other membrane-based processes such as reverse osmosis and nanofiltration for complete and effective treatment of dye and textile industry wastewater.
📰 Tough terrain saves Sikkim’s high-altitude forests
Legal protection of high-reach forests could be key
•Being higher and out of reach is probably saving Sikkim’s high-altitude tropical forests. Scientists find that land-use patterns changed more drastically in the more-accessible lower regions, causing a staggering 16% decline in primary broadleaved forest cover in the Sikkim Himalaya.
•Primary forests, which host native vegetation and are still undisturbed by human activities, are declining worldwide. Globally, more than 40 million hectares of such forest have been converted for other uses since 2000. A majority of this has been in the tropics, where logging and clearing forests for industrial development are concerns. Human activities also transform primary forests into agricultural land and secondary forests (disturbed forests which replace logged primary forests).
•Unfortunately, this is common in the broadleaf forest tracts of India’s Sikkim Himalaya which thrive between 1,000-2,800 metres above mean sea level. When researcher Radhika Kanade of Bengaluru’s Ashoka Trust for Research in Ecology and Environment (ATREE) went looking for primary forest patches in the lower reaches (around 1,000 m) here, she could barely find any. However, most of the slightly higher reaches (2,000-2,800 metres, which were difficult to access due to the terrain), still supported primary forests.
•Wondering if topography, such as the presence of steep terrain, could be influencing this pattern, Kanade and Robert John (Indian Institute of Science Education and Research, Kolkata) studied satellite images from 1990 to 2013 to examine the land-use changes near Sikkim's Teesta river.
•They surveyed several areas between 2011 and 2013 to confirm current land use.
•The team's results, published in the journal Applied Geography, show a 16% decline in primary forest cover in this Eastern Himalaya biodiversity hotspot. This is higher than regional level declines reported so far (such as the 8.4% decline in Southeast Asian forest cover estimated by the Global Forest Resources Assessment in 2015). A staggering 14,740 hectares of primary forest was transformed during the 23-year period — some into secondary forest, parts of which again transitioned to agricultural land.
•The scientists’ hunch was right: elevation, slope and aspect (the direction a slope faces) influenced land-use patterns. Agricultural areas steadily expanded, mainly in the lower regions. Undisturbed primary broadleaved forest is now restricted to higher reaches that are relatively difficult to access and unsuitable for activities like agriculture and agroforestry.
•“These higher-altitude areas are also legally protected and this plays a role too,” says Kanade.
📰 Tackling a silent killer
Mumbai is readying a pilot project to target latent tuberculosis
•The civil administration in Mumbai firmly believes that ‘prevention is better than cure’ and is working on a plan to begin scouting for persons with latent tuberculosis infection (LTBI). These are people who harbour the TB-causing bacteria within, where it can lie dormant. While most never get sick, it can, without warning, manifest as disease in others.
•Mumbai, which is known to be an epicentre of the deadly disease, is already overburdened with active TB cases (as many as 130,000 cases according to latest estimates). It also sees many cases of the worst drug-resistant forms of the disease. Therefore, tackling LTBI may appear premature. However, some experts feel that it is never too early to attack the bacteria from all fronts.
The strategy
•“We have a high burden of active TB cases. But there are wider discussions going on at the Central government-level about LTBI. For Mumbai too, we are discussing the possibility of a pilot project that could help us target the bacteria in advance [of active infection],” says Dr. Daksha Shah, Mumbai TB officer. The authorities are holding consultations with the World Health Organisation (WHO) to take the project further. The civic body follows social contacts of active TB patients and screens them for signs of infection. If there are symptoms, doctors offer them preventive treatment, and if need be, schedule detailed follow-ups to detect signs of an LTBI.
•“In most countries, contacts with a latent infection are put on Isoniazid, a preventive. But can you imagine putting every patient’s contacts on preventives when each such patient may be sharing a room or rooms with 10 to 20 people?” asks Mumbai-based chest physician, Dr. Zarir Udwadia. He recommends sustained follow-ups: “I advise chest x-rays every six months for a patient’s family even if they claim to be feeling well. That way you are likely to detect the disease at an early stage and not when it’s too late.”
•He recollects the case of a young girl who recently went to the U.S. after completing her TB treatment. When her college heard that she had TB, they screened everyone there as a precautionary measure. “It is routine in the West. That’s how they have controlled the infection. But for us, LTBI treatment is not a priority given that we are unable to cope with the burden of drug-resistant TB,” says Dr. Udwadia.
•TB is caused by Mycobacterium tuberculosis , a species of pathogenic bacteria, that is spread through air. The bacteria most often attacks the lungs. When an infected patient sneezes or coughs, the droplets carrying the bacteria spread in the air and any person who inhales them may get infected.
•The WHO too lays emphasis on a specific strategy to tackle latent TB but only in high- and upper middle-income countries with a low incidence of the disease. According to a WHO report, approximately 10% of people with LTBI will develop TB, with the majority of them getting it within the first five years of infection. It says: “Systematic testing and treatment of LTBI in at-risk populations is a critical component of the WHO’s eight-point framework adapted from the ‘End TB Strategy’ to target pre-elimination and, ultimately, elimination in low incidence countries.”
•Other than the mode of air, the latent infection can also be contracted from an improper skin or blood test. Some experts aver that LTBI can often be tackled by maintaining good health and observing coughing and sneezing etiquette. “TB bacilli are extremely intelligent. They can gauge the body’s immunity without moving or multiplying. They lurk within the body for five to eight years and as soon as the body’s immunity weakens, they start multiplying and eating the lungs,” says Dr. Lalitkumar Anande, chief medical officer at the Sewri TB Hospital in Mumbai, and also Asia’s largest.
‘Prep up immunity’
•“Therefore, to win the war against the bacilli, one must keep the immune system upbeat. Additionally, people should not spread the droplets in the air by coughing and sneezing openly. The basic etiquette of using a handkerchief or at least the hand to cover the face should be followed,” says Dr. Anande, who believes that antioxidants and micronutrients are good immunity boosters. He says that the government’s call to end TB by 2025 can be achieved if the public focusses on these basic measures while the health administration aggressively targets active TB cases.
📰 People-centred health care
Technology can help achieve it but mindsets must change too
•The last fortnight saw a lot of high level activity on health care. April 7 was World Health Day, which has the theme of Universal Health Coverage: Everyone, Everywhere. A couple of weeks earlier, on March 24, which is observed as World TB Day, India set itself an extremely ambitious goal. Prime Minister Narendra Modi announced that by 2025, not as far off as you may think, India will completely eradicate TB (“Zero deaths, disease and poverty due to TB”).
An ambitious target
•This is a challenging target for a country that is home to the world’s largest number of TB patients in the world. Consider the facts: The disease kills an estimated 4.8 lakh Indians every year, or 1,400 every day. India adds the most number of TB patients every year — 2.9 million, or 27% of the world’s total. Worse, it is also home to the largest number of TB patients who are resistant to multiple drugs commonly used to treat the disease. India has a quarter of the world’s close to half a million multidrug resistant TB (MDR-TB) patients. According to the Global TB Report of 2017, treatment success rate among MDR-TB patients in India is about 46% and the death rate is around 20%.
•What does it mean to achieve the goal of a TB-free India by 2025? For starters, India needs to achieve a ten-fold increase in the reduction rate of TB every year, from the current baseline of 217 per 100,000 population (in 2015) to 44 per 100,000 population in less than a decade. According to the National Strategic Plan (NSP) for TB elimination, released last year, this will also involve reducing the mortality rate due to TB from the current 32 per lakh population to just three.
•Sounds ambitious? Chew on more facts. According to data in the NSP, this will require upping the number of patients actually notified as TB patients from the current 1.7 million to 3.6 million within the next three years. That may not sound difficult but the NSP report says that the proportion of identified “targeted key affected population” undergoing “active case finding” needs to be 100%. In 2015, this was zero. Targeted key affected population means health workers actively go and test those identified as vulnerable to TB — the poor, the malnourished and those resident in areas where TB is endemic. In other words, nobody was earlier going out and actively trying to find who has TB. Can India’s creaky health care system, even with global funding and support, take this number from zero to 100% in five years?
Challenges ahead
•One of the key problems in tackling TB lies in ensuring that patients, once identified, actually take the prescribed course of medication. To its credit, India does back the TB programme. Medicines are not really a problem, and are provided free to patients. But the course of treatment is long: typically six months to a year. India largely follows the WHO-prescribed DOTS system (Directly Observed Treatment, Short-Course) to deal with this problem. This means that the patient will have to come to the treatment centre for medicines, which will have to be taken in the presence of a health worker and certified.
•This sounds good on paper and does work to some extent (which is why India’s success rate is higher than the global average) but there are problems. For the poor, a trek to the health centre usually means loss of wages. And if the patient cannot make it due to travel, marriage, or livelihood commitments, the treatment is missed, leading to higher drug resistance and a more persistent problem to solve.
Technological solutions
•This is where technology can help. Global software giant Microsoft, for instance, has developed a programme called 99DOTS. In this, each dose is placed in an individual blister pack. Once the patient opens the pack and takes out the pill, a telephone number is seen. All she has to do is give a missed call to that number to log that she has taken the drug. Since the number is visible only after the drug is taken out, there is a high chance that the patient has actually taken the dose. Missed doses trigger SMS alerts and phone counselling by health workers.
•Delhi-based ZMQ Development, a technology-based social enterprise which was recognised last month asThe Hindu BusinessLine’s Change Maker of the Year in Digital Transformation, has come up with an even more foolproof solution. It uses the Video Observed Therapy approach. Patients shoot a selfie video while taking the dose at home with the smartphone provided by ZMQ and upload it. This gives a visual confirmation that the drug is taken. Missed doses trigger alerts and interventions by pre-identified support volunteers in the community.
•ZMQ calls this the Active Compliance System. What both Microsoft’s and ZMQ’s systems do, however, is something much more important — put the patient at the centre of the treatment, freeing them from the need to supplicatebabudom. This is the kind of mindset change that is needed if India is to achieve its ambitious health goals.
📰 Transforming yeast to become plant-like and produce medicines
Recruiting a microbe such as yeast to produce a specific molecule that a plant can make naturally is a true out-of-the-box idea
•Plants are rich sources of medicines and drugs. This has been known since we humans started living together in communities. (Indeed, it appears that even chimpanzees chose to pick and eat specific plants as medicines). Ayurveda, Unani, Siddha, tribal medicine, Oriental medicine and Homeopathy all use plant-based compounds as medicines and tonics. The discipline of organic chemistry has specific branches such as natural products chemistry and medicinal chemistry. Practitioners here collect chosen plants and try to isolate specific molecules from them, study their specific chemical structures, check their effectiveness against chosen diseases (an area called pharmaceutical chemistry).
•A given plant contains thousands of molecules and has them in varying amounts. Often, the ‘drug molecule’ one is looking for occurs in tiny amounts. It is thus not just a ‘needle in a haystack’ problem; one needs many haystacks in order to collect the target compound in a reasonable amount (say several grams) to work with. Natural products chemistry has thus been a very challenging area, and the successful practitioners are considered heroes and decorated with awards and honours. A recent example is the Chinese woman scientist, Dr. Youyou Tu, who was given the 2015 Nobel Prize in Physiology or Medicine for her back-breaking decades-long work of isolating the anti-malarial drug molecule called artemisinin from the Chinese herb Qinghao.
•Once the natural products chemist isolates and determines the actual chemical structure of the drug molecule, he/she attempts to make (synthesise) it in the laboratory. This is yet another challenging and back-breaking task. Since the molecule is three-dimensional in shape, its architecture (or the spatial arrangement of atoms within) can be quite complex. To build such complex molecules in the lab is somewhat akin to the job of an architect putting together a building from bricks and mortar. (Here too, heroes are recognised. One such is the late Professor Robert Woodward of Harvard, whose decades-long successful achievement of the synthesis of several complex molecules fetched him the Nobel Prize in Chemistry in 1965). It was with this analogy in mind that the late Professor Subramania Ranganathan, an outstanding organic chemist, wrote a monograph titled: “The Art of Organic Synthesis”.
•How does Qinghao make artemisinin? It involves over a dozen steps, many of them catalysed by enzymes which are protein molecules. We have been able to decipher each of these steps, and the genes involved in synthesising these enzymes in the plant cells, in fact the whole gene cluster involved in the process. Now, given this knowledge, and given the advances in genetics and genetic engineering, can we make artemisinin in the lab, using genetic engineering methods, rather than organic chemical methods? And if we were to insert this gene cluster into a microbe, say baker’s yeast, will the yeast produce artemisinin? If we can do this, we need not harvest tonnes (‘haystack’) of the herb, but brew the yeast in large cultures, and manufacture the drug in kilogram quantities!
•This idea of recruiting a microbe to make artemisinin (or for that matter any molecule that a plant makes) is a true “Out of the Box” one. If we succeed, we would have made a ‘plant’ out of baker’s yeast - which has been used in homes and bakeries for the last five millennia or more! But this demands that the yeast cells contain (besides their own genome) the genetic cluster that the plant has, in order to produce the desired drug.
Idea worth pursuing
•Thanks to the advances in genetics and genetic engineering, this idea is no longer foolhardy but worth pursuing; so argued Professor Jay Keasling of the University of California, Berkeley, and Dr. Neil Renninger of the company called Amyris. Aided by a grant from the Gates Foundation, their team chemically synthesised the entire gene cluster used by the herb to produce the drug, modified it to suit the yeast cells, and inserted the cluster into yeast cells. Culturing the genetically modified yeast in the laboratory, they found that they could produce artemisinin from yeast. (This landmark paper by V. Hale et al., inAm. J. Trop. Med. Hyg., 77, 198-202, 2007 is accessible free on the web). By 2013, the group had improved the method and has been able to produce as much as 25 grams of this anti-malarial medicine per litre of the culture medium.
•During the last a few years, several other drugs, naturally found in plants and herbs, have been produced in yeast. The most recent is a paper by Li et al., from UC Riverside and Stanford, published in PNAS last month, where they made the anti-cancer drug noscapine (found in the opium-making poppy plant), again using yeast (www.pnas.org/cgi/doi/10.1073/pnas.1721469115). The trick is to identify the cluster of genes involved in making the molecule in the plant cells, make them in the lab, insert them in yeast, optimise the conditions and generate the molecule in yeast, the new plant ‘avatar’. Baker’s yeast (or Khmer as the Arabs call it), known for over five millennia, to leaven bread and to brew alcohol, now has another equally useful role.
📰 Initial step to treat breast, prostate cancer
IIT Gandhinagar team finds biologically active protein yielded by E. coli to be effective
•By using a smartly designed, customised E. coli vector, researchers at Indian Institute of Technology (IIT) Gandhinagar have successfully produced a large quantity (15 mg/ml) of a biologically active protein (human tousled-like kinase-1b or TLK1b) in pure form.
•The reported yield for this protein using bacteria is only about 1 mg/litre. The protein is mainly involved in DNA damage response pathway in breast and prostate cancer cells.
•The team led by Dr. Sivapriya Kirubakaran and Dr. Vijay Thiruvenkatam from the institute’s Discipline of Biological Engineering found a handful of the 120 small molecules they had designed and synthesised were able to inhibit the protein.
•Though the protein is produced in excess in cancer cells, the inhibition, which was as high as 75%, prevents the protein from repairing the DNA damage leading to death of cancer cells.
•DNA gets damaged when cells are exposed to radiotherapy, chemotherapy or other environmental factors.
•The researchers were able to get high yield of the protein by inserting a recombinant DNA into E. coli. The recombinant DNA has a gene that expresses both TLK1b protein and the bacteriophage lambda phosphatase protein.
•The simultaneous expression of both the proteins is responsible for the high yield,” says Dr. Thiruvenkatam, one of the corresponding authors of a paper published in Scientific Reports.
•In the absence of the bacteriophage lambda phosphatase gene, the TLK1b protein produced is not active as it remains insoluble. “The lambda phosphatase gene removes the phosphate so we were able to get the pure, active protein. Getting pure, active protein from bacteria has been a challenge so far,” says Dr. Kirubakaran, the other corresponding author.
•Since the yield has been much more than expected, the researchers are testing the bioactivity and the 3D crystallographic structure of the protein. “There is limited information on this protein’s expression. So we intend studying the protein function and mechanism biochemically and structurally,” she says.
•The team has already biochemically confirmed that the protein produced by the bacteria is active. The next task is to know the precise structure the protein takes inside the cells. “Knowing the crystal structure of the protein will help in identifying the mechanism of DNA repair. It will help us in knowing the amino acid sequence that is responsible for DNA repair,” he says.
•Though a handful of small molecules were found to be effective in inhibiting the protein, the researchers are yet to study the mechanism of inhibition. “By knowing the crystal structure of the protein we can tell the sites where the small molecules get attached leading to inhibition. It will also help us design better small molecule inhibitors,” Dr. Thiruvenkatam says.
•“We are working on two other proteins in the DNA repair pathway which when inhibited using small molecules will increase the chances of cancer cell death. The inhibitors should be used along with chemotherapy or radiotherapy for best results,” says Althaf Shaik, a co-author of the paper.
•“The work we are currently doing is preliminary in nature. Our long-term goal is to know which functional groups on the small molecules needs to be modified to make them more specific so that they target the TLK1b protein present only in the cancer cells,” says Siddhant Bhoir, first author of the paper.
📰 Healing wounds with leather, meat waste
•Protein extracted from discarded animal tissues can now be put to better use — wound healing and human tissue engineering. This waste-to-wealth feat was demonstrated by researchers from the Chennai-based CSIR-Central Leather Research Institute (CSIR-CLRI).
•In the meat industry, tonnes of animal tissues that are rich in collagen (protein) go waste. The researchers have found that various collagenous tissues available as inedible by-products in abattoirs can be successfully used for the production of collagen-based products for biomedical applications. “Collagen has been reported to play a major role in healing of tissues, but their low mechanical strength and fast biodegration has restricted its use. We tried to overcome these limitations by incorporating the collagen with another biopolymer, chitosan, obtained from shells of crustaceans,” says Dr. Chellan Rose, the corresponding author of the paper published in RSC Advances, who has now retired from CLRI.
•The collagen-chitosan scaffold was cross-linked with an amino-acid L-arginine to impart stability. It also helps avoid side-effects caused by toxic chemical cross linkers.
•The freshly prepared 3D scaffolds were first tested in vitro on mouse fibroblasts. The cell population increased significantly in 48 hours suggesting that they were able to anchor to the 3D scaffold and proliferate. For in vivostudies, a small cutaneous wound was created on a lab rat and treated with the new scaffold and covered using micropore tape. Complete wound closure was seen at the end of 14 days with no scar formation.
•Computer simulation studies further examined the possible interactions of the collagen with arginine and chitosan. Molecular docking revealed that the compounds bind well and the arginine helped the stability of collagen-chitosan interaction.
•Scanning electron microscopy studies showed that the scaffold had a uniform, interconnected porous structure with pore size of about 50-400 micrometre. The decreased pore size but high porosity of the material helped in water uptake by the scaffold and facilitated cell migration, adherence and proliferation.
•“This hybrid scaffold is specifically developed for highly exudating wounds to absorb the fluid and to keep the wound dry for faster healing,” explains Mr. S. Udhayakumar, first author of the paper.
•“Even the collagen scraps generated during the different operations of leather making can be used as biomaterial in the field of regenerative medicine. The scaffolds will cost less than the existing collagen-based healing products. Human clinical trials are in progress and the results are encouraging,” says Dr. C. Muralidharan at the Leather Processing Division, CLRI and one of the authors of the paper.
