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Beavers alter their landscape through dams, canals, and felling trees Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Beavers are back in Britain, ‘wood’ you like to know why? 09/07/25, 10:58 Last updated: Published: 03/12/24, 12:05 Beavers alter their landscape through dams, canals, and felling trees This is article no. 3 in a series on animal conservation. Next article: Pangolins: from poached to protected . Previous article: Conserving the California condor Eurasian beavers ( Castor fiber ) transform freshwater habitats so dramatically that they are nicknamed ‘ecosystem engineers’. Their dam-building and tree-felling activities could reduce flood risk and increase biodiversity. After being hunted to extinction centuries ago, beavers have been reintroduced to Britain in both organised and illicit ways. This article will describe where they have been reintroduced in Britain, and the impact they could have. Ecological importance of beavers By building dams, Eurasian beavers alter their habitat - often for the better. Beaver dams are made from wood, stones, and mud. They control the flow of river water, reducing the risk of floods and droughts. The resulting slower water is a good place for amphibians to lay eggs and undergo the aquatic part of their life cycle. As water builds up behind the dam, it converts the area into a wetland - a source of drinking water for animals like bats and an excellent carbon sink. Meanwhile, invertebrates can lay eggs or hide from predators in the spaces within beaver dams ( Figure 1 ). Further up the food chain, beaver dams have complex effects on fish. Although the still water provides habitat for overwintering and rearing young, dams restrict the movement of fish species like salmon. However, most studies have concluded that beaver dams benefit freshwater biodiversity. Dams are not the only way Eurasian beavers improve their landscape. To access food and construction materials easily, beavers dig canals – which make the habitat better drained and more complex. Moreover, beavers gnaw at tree trunks and branches, sometimes knocking over entire trees. This creates deadwood where terrestrial invertebrates can live. Felling trees also allow sunlight to reach the river surface, promoting aquatic plant growth. When beavers gnaw at willow trees, they create propagules, which disperse along the beaver-made canal network and grow downstream. These new willow trees stabilise the river bank and further reduce the flood risk. Humans often trim back trees to stimulate their growth – called coppicing – but beavers do this free of charge. Coppicing, dam building, and canal digging are just a few ways beavers save the human costs of restoring and protecting natural habitats. Extinction and reintroduction However, Eurasian beavers used to be more exploited than appreciated. They were hunted for their fur, meat, and a secretion called castoreum, which is used in perfume and pharmaceuticals. Exactly when and how the beaver population went extinct from Britain is unclear, but the last written record of a beaver is from 1526 in Scotland and 1780 in England. Since then, the British turned wetlands into farmland and forgot about beavers … until recently. After centuries, beavers returned to Scotland in the late 2000s. A handful of beavers were spotted in River Tay about 15 years ago, after either an enclosure escape or an illegal release. There are 114 families in this illegal population, which has genetic origins in Germany. The first official beaver reintroduction occurred in Knapdale Forest, Scotland, in 2009 – but this population did not grow as quickly as the River Tay one. With scepticism, the reintroduction of Eurasian beavers to Scotland was deemed a success, and they became a ‘European Protected Species’ in Scotland in 2019. Seeing Eurasian beavers thriving in Scotland encouraged reintroduction plans in England. In the English county of Devon, River Otter showed signs of beaver presence since 2008 and breeding since 2013. Authorities were worried these illegally released beavers would spread foreign diseases to local wildlife, but the public campaigned to let the beavers be. Public affection for beavers led to the River Otter Beaver Trial in 2015, where two breeding pairs were released into the river after thorough health checks. By 2019, the number of breeding pairs grew to seven ( Figure 2 ). Therefore, beavers have successfully returned to England. Conclusion Beavers alter their landscape through dams, canals, and felling trees. However, in Britain, they were hunted to extinction a long time ago. Although beavers first returned to England and Scotland illegally, they now live in healthy, growing populations. Hopefully they will remain protected and loved by the public, helping us to restore wetlands and improve British freshwater biodiversity. Written by Simran Patel Related article: Vicuna conservation REFERENCES Andersen, L.H. et al. (2023) ‘Can reintroduction of beavers improve insect biodiversity?’, Journal of Environmental Management , 337, p. 117719. Available at: https://doi.org/10.1016/j.jenvman.2023.117719 . Brazier, R.E., Elliott, M., Andison, E., Auster, R.E., Bridgewater, S., Burgess, P., Chant, J., Graham, H., Knott, E., Puttock, A.K., Sansum, P., Vowles, A., (2020) ‘River Otter Beaver Trial: Science and Evidence Report’. Brazier, R.E. et al. (2021) ‘Beaver: Nature’s ecosystem engineers’, WIREs Water , 8(1), p. e1494. Available at: https://doi.org/10.1002/wat2.1494 . Campbell-Palmer, R. et al. (2020) ‘Beaver genetic surveillance in Britain’, Global Ecology and Conservation , 24, p. e01275. Available at: https://doi.org/10.1016/j.gecco.2020.e01275 . Gaywood, M., Batty, D. and Galbraith, C. (2008) ‘Reintroducing the European Beaver in Britain’, British Wildlife , 19, pp. 381–391. Halley, D.J., Saveljev, A.P. and Rosell, F. (2021) ‘Population and distribution of beavers Castor fiber and Castor canadensis in Eurasia’, Mammal Review , 51(1), pp. 1–24. Available at: https://doi.org/10.1111/mam.12216 . Hooker, J. et al. (2024) ‘Re-establishing historic ecosystem links through targeted species reintroduction: Beaver-mediated wetlands support increased bat activity’, Science of The Total Environment , 951, p. 175661. Available at: https://doi.org/10.1016/j.scitotenv.2024.175661 . Wilson, J.B., Bradley, J. and Bremner-Harrison, S. (2024) ‘The short-term impact of Eurasian beavers ( Castor fiber ) post-reintroduction on amphibian abundance and diversity in a lentic environment’, The Glasgow Naturalist , 28(2). Available at: https://doi.org/10.37208/tgn28224 . Project Gallery

Applications of ancient DNA analysis Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Are aliens on Earth? 09/07/25, 10:52 Last updated: Published: 04/10/23, 17:13 Applications of ancient DNA analysis During a recent congressional hearing regarding UFOs held by Mexico, two alleged alien corpses were presented by UFO enthusiast Jaime Maussan. These artefacts were met with scepticism due to Maussan’s previous five claims to have found aliens, all debunked as mummified human remains. To verify the newly found remains as alien, various lab tests have been performed, one being a carbon-14 analysis by researchers at the Autonomous National University of Mexico. This analysis estimated the corpses to be approximately 1000 years old. Determination of the corpses’ genetic make-up is another essential technique for the verification of the supposed alien remains, but is it possible for these ancient remains to undergo DNA analysis? Yes; in fact, there are methods specialised for cases such as these that enable ancient DNA (aDNA) analysis. The relatively recent advent of high throughput sequencing technology has streamlined DNA sequencing into becoming a more rapid and inexpensive process. However, aDNA has fundamental qualities that complicate its analysis such as postmortem damage, extraneous co-extracted DNA and the presence of other contaminants. Therefore, extra steps are essential in the bioinformatics workflow to make sure that the aDNA is sequenced and analysed as accurately as possible. So, let’s talk about the importance of aDNA analysis in various areas and how looking at the genetics of the past, and potentially space, can unearth information for modern research. Applications of aDNA sequencing and analysis Analysis of ancient DNA is a useful technique for the discovery of human migration events from hundreds of centuries ago. For example, analyses of mitochondrial DNA (mtDNA) have repeatedly substantiated the “Recent African Origin” theory of modern human origins; the most common ancestor of human mtDNA was found to exist in Africa about 100,000-200,000 years ago. There have also been other recent studies within phylogeography; an aDNA study on skeletal remains of ancient northwestern Europeans carried out in 2022 showed that mediaeval society in England was likely the result of mass migration across the North Sea from the Netherlands, Germany and Denmark. Thus, these phylogeographic discoveries improve our knowledge of the historic evolution and migration of human populations. Paleopathology, the study of disease in antiquity, is another area for which ancient DNA analysis is important. Analysis of DNA from the victims of the Plague of Justinian and the Black Death facilitated the identification of Yersinia Pestis and determined it as the causal agent in these pandemics. The contribution of aDNA analysis is consequently important to reveal how diseases have affected past populations and this derived genetic information can be used to identify their prevalence in modern society. Exciting yet debatably ethical plans for the de-extinction of species have also been announced. The biotech company Colossal announced plans in 2021 to resurrect the woolly mammoth among other species such as the Tasmanian tiger and the dodo bird. Other groups plan to resurrect the Christmas Island rat and Steller’s sea cow. In theory, this is exciting, or scary from certain ecological perspectives, but is complicated in practice. Even though the number of nuclear genomes sequenced from extinct species exceeds 20, there has been no restoration of species to date. Are aliens on Earth? Thus, ancient DNA analysis can be applied to a multitude of areas to give historical information that we are able to carry into the modern world. But, finally, are these ‘alien’ corpses legitimately from outer space? José Zalce Benitez is the director of the Health Sciences Research Institute in the secretary of the Mexican Navy’s office and he reports on the scientists’ findings. The DNA tests were allegedly compared with over one million species and found not to be genetically related to “what is known or described up to this moment by science.” In essence, genetic testing has not conflicted with Maussan’s claim that these remains are alien so the possibility of their alien identity cannot yet be dismissed. However, this genetic testing does not appear to be peer-reviewed; NASA is reportedly interested in the DNA analysis of these corpses, so we await further findings. Ancient DNA analysis will undoubtedly provide intriguing information about life from outer space or, alternatively, how this DNA code was faked. Whatever the outcome, ancient DNA analysis remains an exciting area of research about life preceding us. Written by Isobel Cunningham Related article: Astro-geology of Lonar Lake Project Gallery

What they are, uses, and future outlook Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Advancements in Semiconductor Laser Technology 08/07/25, 16:19 Last updated: Published: 23/06/24, 09:39 What they are, uses, and future outlook Lasers have revolutionised many fields starting from the telecommunications, data storage to medical diagnostics and consumer electronics. And among the semiconductor laser technologies, Edge Emitting Lasers (EEL) and Vertical Cavity Surface Emitting Lasers (VCSEL) emerged as critical components due to their unique properties and performance. These lasers generate light through the recombination of electrons and holes in a semiconductor material. EELs are known for their high power and efficiency and they are extensively used in fiber optic communications and laser printing. VCSELs on the other hand are compact and are used for applications like 3D sensing. Traditionally VCSELs have struggled to match the efficiency levels of EELs however a recent breakthrough particularly in multi junction VCSEL, has demonstrated remarkable efficiency improvements which place the VCSELs to surpass EELs in various applications. This article focuses on the basics of these laser technologies and their recent advancements. EELs are a type of laser where light is emitted from the edge of the semiconductor wafer. This design contrasts with the VCSELs which emit light perpendicular to the wafer surface. EELs are known for their high power output and efficiency which makes them particularly suitable for applications that require long-distance light transmission such as fiber optic communications, laser printing and industrial machining. EELs consist of an active region where electron hole recombination occurs to produce light. This region is sandwiched between two mirrors forming a resonant optical cavity. The emitted light travels parallel to the plane of the semiconductor layers and exits from the edge of the device. This design allows EELs to achieve high gain and power output which makes them effective for transmitting light over long distances with minimal loss. VCSELs are a type of semiconductor laser that emits light perpendicular to the surface of the semiconductor wafer unlike the EELs which emit light from the edge. VCSELs have gained popularity due to their lower threshold currents and ability to form high density arrays. VCSELs consist of an active region where electron-hole recombination occurs to produce light. This region is situated between two highly reflective mirrors which forms a vertical resonant optical cavity. The light is emitted perpendicular to the wafer surface which allows for efficient vertical emission and easy integration into arrays. Recent advancements in VCSEL technology marked a significant milestone in the field of semiconductor lasers. And in particular the development of multi junction VCSEL which led to the improvements in power conversion efficiency (PCE) of the laser. Research conducted by Yao Xiao et al. and team has demonstrated the potential of a multi junction VCSELs to achieve efficiency levels which were previously thought unattainable. This research focuses on cascading multiple active regions within a single VCSEL to enhance gain and reduce threshold current which leads to higher overall efficiency. The study employed a multi-junction design where several active regions are stacked vertically within the VCSEL. This design increases the volume of the gain region and lowers the threshold current density resulting in higher efficiency. Experimental results from the study revealed that a 15-junction VCSEL achieved a PCE of 74% at room temperature when driven by nanosecond pulses. This efficiency is the highest ever reported for VCSELs and represents a significant leap forward from previous records. Simulations conducted as part of the study indicated that a 20-junction VCSEL could potentially reach a PCE exceeding 88% at room temperature. This suggests that further optimization and refinement of the multi-junction approach could yield even greater efficiencies. The implications of this research are profound for the future of VCSEL technology. Achieving such high efficiencies places VCSELs as strong competitors to EELs particularly in applications where energy efficiency and power density are critical. The multi junction VCSELs demonstrated in the study shows promise for a wide range of applications and future works may focus on optimizing the fabrication process, reducing thermal management issues and exploring new materials to further enhance performance. Integrating these high-efficiency VCSELs into commercial products could revolutionize industries reliant on laser technology. Written by Arun Sreeraj Related articles: The future of semi-conductor manufacturing / The search for a room-temperature superconductor / Advances in mass spectrometry Project Gallery

The future of precision healthcare: nanocarriers Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Nanomedicine and targeted drug delivery Last updated: 17/07/25, 10:53 Published: 17/07/25, 07:00 The future of precision healthcare: nanocarriers In recent years, nanomedicine - the application of nanotechnology in healthcare - has emerged as a powerful and versatile area of research and is rapidly developing with many promising opportunities in the medical sciences. Nanocarriers are being developed for pharmaceuticals for example, with uses in cancer treatment and in particular targeted drug delivery. In nanomedicine, the materials are engineered at the nanoscale, with sizes ranging from 100 to 1000 nm, and can be used to perform specific biomedical tasks. These nanomaterials, such as nanoparticles, are often made from crosslinked polymer chains and can encapsulate therapeutic molecules for delivery within the body. Their small sizes give them unique properties, as they can interact with cells at a molecular level, and be designed to respond at specific times and locations, which can be directed to specific tissues or environments. Since the coronavirus disease (COVID-19) pandemic, nanoparticle-based drug delivery platforms have been widely studied - lipid nanoparticles were used in the vaccine to combat the virus. Being highly successful, and looking ahead, research and development in nanomedicine-based drug delivery is expected to keep growing, as the interest in more precise and effective treatments continues to rise. How can nanoparticles be used for drug delivery? A significant challenge in conventional drug therapies lies in their limited solubility, which can reduce the effectiveness of a drug and cause harmful side effects. Nanoparticles offer a solution to this: they can encapsulate poorly soluble drugs, protecting them from degradation in the body, and this allows them to be carried safely to the targeted tissues. This localised delivery improves the drugs’ biodistribution, and reduces systemic toxicity, which is a common concern in treatments such as chemotherapy, where healthy tissues in the body are damaged. Nanoparticles in particular are exciting as they have tuneable surface properties and a high surface to area volume ratio. This means their physical and chemical behaviours can be adjusted - for example through changing their sizes, shapes, or surface chemistries - to match a specific medical application or target. In addition to this, nanoparticles undergo the enhanced permeability and retention (EPR) effect; a phenomenon where they naturally accumulate in tumour tissues due to the leaky nature of tumour blood vessels. This effect improves the targeting precision, and drugs can be delivered more efficiently to cancer cells, while sparing healthy ones one, avoiding unnecessary damage and side effects to the patient. While drug delivery is a major focus, nanomedicine research also plays a role in diagnostics. Nanoparticles can be engineered to function as contrast agents in medical imaging, helping doctors detect diseases earlier and monitor treatments more accurately. There is also a growing interest in using nanomaterials for tissue regeneration, by creating scaffolds that support the repair and regrowth of damaged tissues. As research continues, nanomedicine holds promise for tacking some of the most pressing challenges in modern healthcare - from treating cancer more safely to developing new vaccines and personalised therapies. Though there are some hurdles, particularly around large-scale manufacturing and regularly approval, the path ahead for nanomedicine has huge potential. As the field of nanomedicine continues to grow, it shows great promise in reshaping healthcare with treatments that are smarter, safer, and more effective - ultimately improving patient outcomes and transforming the way we fight disease. Written by Saanchi Agarwal Related articles: Nanomedicine / Nanoparticles and diabetes treatment / Nanoparticles and health / Nanogels Project Gallery

Its significant role in immunity Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link The mast cell 14/07/25, 14:57 Last updated: Published: 05/08/23, 09:55 Its significant role in immunity The mast cell The mast cell is the first white blood cell to respond to infection or injury; they are located in many connective tissues throughout the body, especially in areas that introduce foreign bodies such as the gastrointestinal tract, respiratory epithelium and the skin. Mast cells are a crucial part in adaptive and innate immunity- in response to pathogens, allergens and toxin exposure they release chemicals and recruit other immune cells. They are created from pluripotent progenitor cells of myeloid lineages; these cells differentiate due to exposure and influence of stem cell factors. There are two types of mast cells in the human body, the first is called TC mast cells and contains tryptase, proteases and chymotryptic proteinase, the second is know as a T mast cell which contains only tryptase. The two types of mast cells are mucosal and connective tissue mast cells: mucosal mast cell are found mostly in the respiratory tract and the gut. Mast cells are found in three forms, granulated, spreading and intact. Intact mast cells lay in the epithelial tissue, the less common spreading mast cells are found in the connective tissues, and granulated mast cells are those which have released their mediators. These mediators reside in the cytoplasm of the mast cell- these include tryptases, heparin, histamine, cytokines, chymase, leukotrienes, TNF- alpha and many more. Mast cells are coated in IgE antibodies that crosslink (bind) to allergen proteins, which ultimately triggers degranulation. Mast cell disorders Abnormal growth of mast cells leads to a variety of issues. Mast cell activation syndrome in its primary state is caused by mast cell clone overproduction resulting in mastocytosis. This can lead to hives, gastric symptoms, and anaphylaxis. In some cases aggressive mastocytosis can lead to death. Cutaneous mastocytosis causes redden lesions of the skin and is most common in infants; systemic mastocytosis is most common in adults, led by the accumulation of mast cells in the intestines, organs, and bone marrow. Systemic mastocytosis includes the rare leukaemia and sarcoma forms. Mast cell activation syndrome in its secondary state is in an IgE -mediated hypersensitive response to external factors, that contributes to the release of pro-inflammatory cytokines and increases blood flow. However, it is too abundant, as the mast cells trigger far more granulation than that which is required. Idopathic mast cell activation is severe responses to the exposure of pathogens, toxins and other triggers. In idiopathic mast cell activation many patients can develop anaphylactic allergic reactions, which can present as difficulty breathing, swelling and hives. Conclusion Mast cells play a crucial role in biological defence and are derived from stem cells in the bone marrow. They come in different forms and locations, delivering an efficient response to injury and infection. When unregulated, they can lead to the development of disorders- ranging from mild rashes to severe anaphylaxis. Written by Lauren Kelly Project Gallery

The 14-day rule and stem cell-based embryo models Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Regulation and policy of stem cell research Last updated: 20/10/25, 14:40 Published: 23/10/25, 07:00 The 14-day rule and stem cell-based embryo models This is the last article (article no. 3) in a three-part series on stem cells. Previous article: The role of mesenchymal stem cells in regenerative medicine. Welcome to the final article in this series of three articles about stem cells. Article 1 was an overview of stem cells, and Article 2 focused on mesenchymal stem cells. In Article 3, I will look at the regulation and policy of stem cell research, which is important given the rapidly changing landscape of stem cell research. Introduction If used effectively, stem cells can be used in treating diseases, understanding human development, and more. For example, a recent paper published in September 2025 explains how scientists created embryos from human skin DNA, in an experimental process they named “mitomeiosis”. Here, the scientists attempted to force the egg cell to divide to remove half of its chromosomes so it could be fertilised like a normal egg cell. While mitomeiosis was unsuccessful in creating viable egg cells, new advancements like this raise ethical questions about the use of stem cells, especially those derived from embryos. As a result, policies and regulations must be created and followed to ensure stem cells are used ethically and appropriately. Two major topics in this policy landscape are the 14-day rule for using human embryos and the creation of Stem Cell-Based Embryo Model (SCBEM) frameworks. The 14-day rule One of the most widely known restrictions in the field of stem cells is the 14-day rule. The 14-day rule prohibits scientists from culturing human embryos in vitro (in the laboratory) beyond 14 days or the appearance of the primitive streak. The primitive streak is a developmental marker signalling the point at which an embryo is biologically individualised. The appearance of this streak also marks the beginning of gastrulation, which is when embryonic cells start differentiating into the three primary germ layers: endoderm, mesoderm, and ectoderm. A timeline of human embryo development from day 0 to day 14 is shown in Figure 1 to help visualise the different stages. In the UK, the 14-day rule is a law under the Human Fertilisation and Embryology (HFE) Act 1990 (as amended 2008) . These human embryos are either donated with consent for research purposes due to no longer being needed, are unsuitable for fertility treatments, or are embryos created explicitly from donated sperm and eggs for research purposes. However, scientific advances have meant that human embryo cultures have now become advanced, resulting in embryos being destroyed at the 14-day deadline due to the law. For example, in 2016, researchers developed new in vitro culture systems that allowed human embryos to be maintained in the lab up to the 12th and 13th day of development. This had previously not been possible. Unfortunately, the experiments had to be stopped because they were approaching the 14-day legal limit. Therefore, scientists have questioned whether the 14-day rule is still fit-for-purpose, and if not, how it could be amended in a way that still ensures ethical and appropriate use of these cells. A specific area of development that scientists do not have a lot of information on is the “black box” period, which includes the moment of gastrulation, happening around day 14-15. Having further knowledge of gastrulation could be used to improve the success rate of In Vitro Fertilisation (IVF), by helping scientists to understand possible causes of early miscarriage and implantation failure, and working to mitigate those. Because of this debate, the Nuffield Council on Bioethics has launched a project to better understand the arguments for and against extensions to the 14-day limit on human embryo research. The Council aims to use this project to provide decision-makers, such as policymakers, with the evidence they need to decide whether to extend the time limit. Regulating Stem Cell-Based Embryo Models (SCBEMs) There is also the development of SCBEMs to consider, as seen in Figure 2 . SCBEMs are also called embryoids or embryo models. They are complex, organised three-dimensional structures derived from pluripotent stem cells, which are cells that can differentiate into all cells in the human body. SCBEMs replicate certain features and processes of embryonic development, meaning they can provide new insights into stages of early human development that have been normally inaccessible to scientists. However, SCBEMs are not defined as embryos under existing laws, like the HFE Act 1990, meaning there is a policy and regulation gap covering these structures. To fill this gap, researchers recently created the first-ever UK guidelines for generating and using SCBEMs in research. The new SCBEM Code of Practice was published in July 2024 and has clear guidance and standards, increasing the transparency of research that will be conducted using SCBEMs. The Code requires that research have well-justified scientific objectives and adhere to an approved culture period, the minimum duration needed to achieve the scientific objective. For example, the Code prohibits the transfer of human SCBEMs into a human or animal womb. Furthermore, adherence to the Code requires that a dedicated SCBEM Oversight Committee be created to review and approve proposed work. An SCBEM Register is also needed to record information about successful applications. Both of these increase the transparency and openness of research using SCBEMs. Future of regulation and policy of stem cell research Given the rapid pace of development in stem cell research, policies and regulations must be created and followed to ensure ethical and appropriate use of these cells. The review by the Nuffield Council on Bioethics regarding the 14-day rule will be important in determining if the rule should be extended. The extension could allow scientists to study developmental stages such as gastrulation, currently part of the “black box” period of development occurring after 14 days. The creation of the UK's first-ever SCBEM Code of Practice in July 2024 has introduced guidelines to fill the existing policy gap, requiring research using these models to have well-justified scientific objectives, follow approved culture periods, and be reviewed by an Oversight Committee to ensure transparency and ethical use. However, there is a need for stronger regulations, as opposed to guidelines, for using SCBEMs, and it is an important example of where policy needs to continue to be developed. Written by Naoshin Haque Related articles: Animal testing ethics / How colonialism, geopolitics and health are interwoven Project Gallery

And its chemical effects Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Exposing medication to extreme heat 09/07/25, 14:09 Last updated: Published: 08/10/23, 16:18 And its chemical effects Introduction The majority of us look forward to when summer is just around the corner. It is a time for parents to start planning days off to be able to go on holiday with their kids to relax from their studies and enjoy sunsets at the beach. But for people who take medication, whether this just be a week-long course of antibiotics or for long-term conditions, summer may also be a chance for some negligence to occur. Specifically, alongside making sure you have applied SPF to protect your skin from the sun’s rays, you should also protect your medicine as well. This applies to both oral and non-oral drugs. Experts at The Montreal Children’s Hospital say that “many prescription drugs are very sensitive to changes in temperature and humidity”; in this article, we will therefore discuss the effect of extreme heat on drugs from a medicinal chemistry perspective. Factors affecting drug activity due to heat Certain drugs may begin to degrade before their expiry date if not stored appropriately. This affects the efficacy, which is the maximum biological response that is achievable with a certain drug. A dose-response curve can be plotted (see Figure 1 ) to show the relationship between the two variables; the label Emax refers to the efficacy. During hot weather, the structure of the drug can change and therefore unable to bind to its target, causing a lowered and shifted Emax to be seen. Simply put, the medication will not relieve your symptoms as effectively. Another physiochemical property of a drug that can be altered in the heat is the potency. Many people confuse this term with efficacy, but potency refers to the concentration of a drug required to achieve 50% of its maximum therapeutic effect i.e., half the Emax. Potency is therefore also known as EC50, which abbreviates for ‘half maximal effective concentration’. The lower the concentration needed, the more potent your drug is. Like reduced efficacy, the drug’s potency will also decrease in the heat due to altered chemical structure. For drugs like antibiotics, it is crucial to note that if potency is reduced significantly, it could risk infection spreading to other parts of the body as the medication will not fight off bacteria as well as it should. Potentially dangerous! Finally, drug absorption is when a drug moves into the bloodstream after being administered. The chemical structure of the drug and the environment in which it is present hugely affects this; for example, if a lipophilic (‘fat loving’) drug is also present in a lipophilic surrounding, fast absorption is seen as they work well with each other. As you have probably guessed, high temperatures outside of the body can reduce drug absorption due to the above factors mentioned, as the drug is not in its optimal structure to be absorbed effectively. Examples of medicine that are heat sensitive Here is a list of some medicines that require extra care to prevent the above: 1) Nitroglycerin – used to treat chest pains for those with cardiovascular disease. It is especially sensitive to heat or light as it degrades very fast. Dr. Sarah Westberg, a professor at The University of Minnesota College of Pharmacy, says you should follow the storage instructions and replace them regularly. 2) Some antibiotics – research has shown that ampicillin, erythromycin, and furosemide show a reduction in activity in the heat, although this was found after storing them for a year in a car with a temperature exceeding 25 degrees Celsius. Other antibiotics such as cefoxitin are shown to have some “stability in warmer climates”. 3) Levothyroxine – used to treat an underactive thyroid, also known as hypothyroidism. This drug should be stored between 15 to 30 degrees Celsius, although even 30 is quite high so the lower the temperature the better. Interestingly, levothyroxine isn’t heat sensitive itself, it is the fact that the body becomes sensitive to the drug and may make a person feel strange in the heat. 4) Metoprolol succinate – used to treat high blood pressure, also known as hypertension, and heart failure in emergencies . The ideal storage conditions for this drug are 15 to 30 degrees Celsius, like Levothyroxine. Key things to look out for with your medicine in the heat Below are the 2 main things you should be checking for before taking your medicine in the summer: 1) Change in colour – Light can initiate all sorts of reactions, such as oxidation. If, for example, your medicine that is normally white has now changed into a different colour, this suggests that a reaction has taken place within your drug and will not be effective when administered. 2) Change in texture – Similar to change in colour, if a normally solid, oral tablet has become soft then this also suggests that the medication will not be as effective when consumed. How you can prevent your medicine from degrading To make sure you do not contribute to wasting medicine, you should do the following: 1) Check storage information – for any medication that you take, this will let you know how to store them correctly. 2) Travel with care – do not pack prescription drugs into your luggage, as it will almost always become very warm due to the surrounding environment. Instead, carry your medicine with you with the labels still on. 3) Do not leave medicine in any vehicle – everyday vehicles such as cars tend to get warm after a period , which can affect the colour and texture of your medicine. 4) Careful deliveries – for those who have their medicine delivered to them, you can request for your local pharmacy to deliver your medicine in temperature-controlled packages. Summary As discussed, chemicals in the majority of over-the-counter prescription drugs are heat sensitive and should therefore be handled with care, to prevent degradation of the drug. Changes in colour and texture are signs of degradation, which result in loss of efficacy, absorption, and potency. However, many other pharmacological factors interfere, so scientists especially involved in drug synthesis should (or continue to) take great precautions with the manufacturing process. Drugs are costly to make and require a lot of time, so the takeaway is to store them correctly! You should contact your pharmacist if you are still unsure about your prescription(s). Written by Harsimran Kaur Sarai Project Gallery

Explaining The Pain Gate Theory Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Gatekeepers of pain: how your body decides what hurts Last updated: 18/09/25, 08:40 Published: 18/09/25, 07:00 Explaining The Pain Gate Theory Pain is an unpleasant bodily sensation that’s usually linked to actual or potential tissue damage. It often acts as the body’s warning system, protecting us from further harm. Now picture this: you hit your leg, and it hurts—but then you instinctively start rubbing it, and the pain begins to ease. Why does that happen? That’s where the Pain Gate Theory (also known as The Gate Theory of Pain, or The Gate Control Theory of Pain) comes in. It’s one of the most fascinating ideas in pain science because it explains how pain isn’t just about injury— it’s also about how our nervous system processes it. Pain can vary greatly between individuals and even in the same person under different circumstances. This variation is due to the fact that pain is not just a physical experience, but also influenced by emotions, attention, and context. The Pain Gate Theory was first coined in 1965 by Ronald Melzack and Patrick Wall to explain this phenomenon. It states that a stimulus must travel through the substantia gelatinosa in the dorsal horn of the spinal cord, the transmission cells and the fibres in the dorsal column in order to have an effect. The substantia gelatinosa acts as a ‘gate’, mediating which signals are able to pass through the nervous system to the brain. As to whether the gate closes is influenced by an array of factors. How does it work? The below figure depicts the relationships in The Pain Gate Theory. The gate mechanism is influenced by the activity of the larger diameter fibres (A-beta) which usually inhibit transmission and the small diameter fibres (A-delta and C) which increase transmission. Take our analogy from earlier about rubbing your leg: when you do this, the large fibres carrying non painful stimuli like touch and pressure are activated. This causes the gate to be ‘closed’ which blocks the pain signals being transmitted by the small fibres. This concept is so interesting as it opens doors to viewing pain holistically; pain is influenced by touch, thoughts and emotions, which explains why you may not notice pain as much when your super excited about something or why placebos have been proven to work in some cases. In a clinical sphere, this theory has opened the door to many pain management techniques, for example Transcutaneous Electrical Nerve Stimulation (TENS), which selectively stimulates A-beta fibres leading to a consequential inhibition in A-delta and C fibres, preventing pain-related signals reaching the brain. It also has been utilised in physiotherapy, labour and chronic pain treatments. One main limitation of this model is its inability to explain certain types of pain like phantom limb since it relies on the assumption that pain requires an input from a limb to the spinal cord . This has led to the development of more advanced models like the neuromatrix model which acknowledges the fact that the brain can create pain on its own. In conclusion, the bottom line is that The Pain Gate Theory was groundbreaking in our understanding of how pain works. Understanding pain as a brain-and-body experience opens the door to innovative treatments that may one day make pain more manageable, or even preventable. Written by Blessing Amo-Konadu Related articles: Ibuprofen / Anthrax toxin to treat pain REFERENCES Cho, In-Chang, and Seung Ki Min. “Proposed New Pathophysiology of Chronic Prostatitis/Chronic Pelvic Pain Syndrome.” Urogenital Tract Infection , vol. 10, no. 2, 2015, p. 92, https://doi.org/10.14777/uti.2015.10.2.92 . Accessed 29 June 2020. Merrick, Mark. “Gate Control Theory - an Overview | ScienceDirect Topics.” Sciencedirect.com , 2012, www.sciencedirect.com/topics/medicine-and-dentistry/gate-control-theory . Tashani, O, and M Johnson. “Transcutaneous Electrical Nerve Stimulation (TENS). A Possible Aid for Pain Relief in Developing Countries?” Libyan Journal of Medicine , vol. 4, no. 2, 10 Dec. 2008, pp. 77–83, www.ncbi.nlm.nih.gov/pmc/articles/PMC3066716/pdf/LJM-4-062.pdf , https://doi.org/10.4176/090119 . The British Pain Society. “What Is Pain?” Britishpainsociety.org , July 2020, www.britishpainsociety.org/about/what-is-pain/ . Trachsel, Lindsay A., et al. “Pain Theory.” PubMed , StatPearls Publishing, 17 Apr. 2023, www.ncbi.nlm.nih.gov/books/NBK545194/ Project Gallery

Restoring cardiac tissue and reducing heart failure Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Why is there a need for cardiac regeneration? Last updated: 13/03/25, 11:37 Published: 06/03/25, 08:00 Restoring cardiac tissue and reducing heart failure Cardiovascular disease (CVD) remains a predominant cause of morbidity and mortality on a global scale. Among its various manifestations, heart failure (HF) stands out as a significant public health concern, with a prevalence exceeding 23 million individuals worldwide. Heart failure, especially after a heart attack (myocardial infarction) or ischemic heart disease, is a major challenge. The five-year survival rate is less than 50%. In these patients, functional cardiomyocytes are substantially lost (cardiomyocytes refer to cardiac muscle cells). The remaining cardiomyocytes often attempt to compensate for this loss; however, this compensatory mechanism can lead to scar tissue formation, subsequently compromising the overall functionality of the cardiac muscle. Despite numerous advancements in medical science and therapeutic interventions, restoring lost cardiomyocytes in the adult mammalian heart remains a significant obstacle due to its poor regenerative capacity. Consequently, there exists an urgent need for novel therapeutic approaches. Cardiac regeneration has emerged as a promising field of research focused on restoring cardiac tissue and reducing heart failure, offering hope for improved clinical outcomes in affected patients. Approaches for cardiac regeneration Cardiac regeneration has emerged as a pivotal area of research, and various innovative strategies, including stem cell therapies and gene therapy, are being explored. Stem cell therapies: Stem cell therapies utilise the ability of stem cells to differentiate into cardiomyocytes or release factors that promote tissue repair. Preclinical studies involving animal models and early-phase clinical trials have demonstrated that stem cell interventions can enhance cardiac function. However, significant challenges remain concerning the efficacy and safety of these therapies in human subjects, necessitating further investigation. Gene therapy: Gene therapy delivers specific genes that directly support cell proliferation, differentiation, and survival to damaged cardiac tissue. Introducing these genes can activate specific intracellular signalling pathways, resulting in the replication and maturation of cardiac muscle cells. Ultimately, this strategy aims to restore normal heart function and improve cardiac health. Benefits of cardiac regeneration Cardiac regeneration has the potential to significantly enhance survival rates and improve the quality of life for patients with heart conditions. Compared to heart transplantation, cardiac regeneration offers a less invasive alternative with fewer complications related to immune rejection and lifelong immunosuppressive therapy. Some of the potential benefits of cardiac regeneration are: Replacing the scar formation and improving heart function Reduce the dependency on medications Alternative to heart transplantation Reducing the healthcare costs Challenges to cardiac regeneration Cardiac regeneration remains a complex field marked by ethical considerations and scientific challenges that require thorough exploration. Stem cell therapy limitations include low engraftment rates, potential tumorigenesis, and difficulty effectively integrating host cardiac tissue. Additionally, immune rejection poses a substantial risk, affecting safety and efficacy. Beyond biological hurdles, the high cost of research, treatment development, and patient care presents a significant challenge to widespread adoption. Regulatory approval processes add another layer of complexity, as therapies must meet stringent safety and efficacy standards before clinical use. Furthermore, scalability remains an issue, as translating experimental techniques into large-scale, cost-effective treatments is a major obstacle in making cardiac regeneration accessible to a broader population. Moreover, it is imperative to deepen our understanding of the roles played by non-cardiomyocyte cell types such as endothelial cells, fibroblasts, and immune cells in cardiac regeneration. Conclusion Cardiac regeneration is a ray of hope for heart patients, significantly enhancing their chances of survival and quality of life. Therefore, cardiac regeneration demands thorough exploration, as it has the potential to transform the treatment and management of cardiovascular disease. Written by Prabha Rana Related article: Hypertension REFERENCES Baccouche, B. M., Elde, S., Wang, H., & Woo, Y. J. (2024). Structural, angiogenic, and immune responses influencing myocardial regeneration: a glimpse into the crucible. Npj Regenerative Medicine, 9(1), 18. https://doi.org/10.1038/s41536-024-00357-z Pezhouman, A., Nguyen, N. B., Kay, M., Kanjilal, B., Noshadi, I., & Ardehali, R. (2023). Cardiac regeneration - Past advancements, current challenges, and future directions. Journal of Molecular and Cellular Cardiology, 182, 75–85. https://doi.org/10.1016/j.yjmcc.2023.07.009 Sacco, A. M., Castaldo, C., di Meglio, F. di, Nurzynska, D., Palermi, S., Spera, R., Gnasso, R., Zinno, G., Romano, V., & Belviso, I. (2023). The Long and Winding Road to Cardiac Regeneration. Applied Sciences, 13(16), 9432. https://doi.org/10.3390/app13169432 van der Pol, A., & Bouten, C. V. C. (2021). A Brief History in Cardiac Regeneration, and How the Extra Cellular Matrix May Turn the Tide. Frontiers in Cardiovascular Medicine, 8. https://doi.org/10.3389/fcvm.2021.682342 Wang, J., An, M., Haubner, B. J., & Penninger, J. M. (2023). Cardiac regeneration: Options for repairing the injured heart. Frontiers in Cardiovascular Medicine, 9. https://doi.org/10.3389/fcvm.2022.981982 Project Gallery

Known as microbial endocrinology, it is a complex field Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Investigating the interplay of hormones and the microbiome 10/07/25, 10:19 Last updated: Published: 08/11/24, 12:00 Known as microbial endocrinology, it is a complex field The microbiome The human body hosts a vast ecosystem of bacteria, with trillions crawling on our skin, colonising our gut, and living throughout our bodies. Most of these microbes serve to protect us against infections influencing our metabolism and even our behaviour. However, scientists have started to question the mechanisms by which these bacteria affect our bodily functions and characteristics. Scientists have studied these communities of microorganisms residing within our bodies and the genes they contain, yielding new and exciting perspectives… …Welcome to the human microbiome. The microbiome is the dynamic community of microorganisms (like fungi, bacteria and viruses) that exist in a particular environment. In humans, the term is most often used to describe the collection of microorganisms that inhabit a particular body area, such as the gastrointestinal tract, mouth or skin. While a person’s core microbiome is established within the first few years of life, its composition can shift over time in response to factors like medication, such as potent antibiotics and environmental factors. Researchers have uncovered that the gastrointestinal microbiota can influence some physiological processes, including a direct line of communication between the gut and the brain. But what facilitates this dialogue? What mechanisms enable the gut to relay signals to the brain? The answer is hormones. Hormones and the endocrine system The endocrine system is a network of glands that produce and release chemical messengers known as hormones. They travel via the bloodstream and bind to specific receptors on their target tissues. This binding of hormones to their receptors triggers a response in the target tissue. For instance, during stressful situations, epinephrine (also known as adrenaline) is produced by the adrenal medulla, the inner region of the adrenal glands. This hormone, released into the bloodstream, acts on target tissues such as the heart, where it increases heart rate. Hormones regulate most of the body’s vital functions through their release. Some of these crucial processes include growth, metabolism, and reproduction. In the following sections, however, we specifically focus on how hormones influence the microbiome. The interactions between hormones and the microbiome Exploring the relationship between hormones and the microbiome is known as microbial endocrinology; it is a complex field because there are numerous interactions to account for, and the effects of each one can have lasting impacts on human physiology. For example, epinephrine and norepinephrine can lead to more bacteria, notably E. coli and Pseudomonas aeruginosa , signifying that imbalance could harm humans. Also, parts of the host, ranging from mood to gender, impact hormones, bacterial presence and activity ( Figure 3 ). An emerging area of microbial endocrinology is how the microbiome and sex hormones engage with each other in disease and female health. One paper noted that disorders from metabolic syndrome (MetS) to type 2 diabetes (T2D) have distinctions in the levels of sex hormones and gut microbiota, indicating that they are essential to understanding in developing those conditions. The influence of gut microbiota on sex hormones can occur through various mechanisms, such as bacteria controlling the activity and expression of endocrine receptors and even bacteria metabolising sex hormones; this knowledge can help create treatments against polycystic ovarian syndrome and ovarian cancer, among other diseases that usually impact females due to gut microbiome imbalances ( Figure 4 ). Another part of microbial endocrinology being researched is how the microbiome impacts human growth. In one study involving adult male mice, decreased growth hormone (GH) led to undeveloped microbiomes, while surplus GH was linked to an expanded microbiome; this depicts that bacteria influences development via the growth hormone-insulin-like growth factor 1 (GH-IGF-1) axis; maintaining a steady dynamic between the microbiome and this axis is vital for development ( Figure 5 ), particularly in children. In puberty, hormones and the gut microbiome interact, as observed in obesity and precocious puberty. Hence, a deeper awareness of the bacteria and sex hormones during puberty is crucial to designing targeted medicines for growth disorders. Moreover, patients with GH-secreting pituitary adenoma (GHPA) have modified gut microbiota, like increased Alistipes shahii and Odoribacter splanchnicus . Still, more research is needed to investigate this. Conclusion The microbiome refers to the millions of microorganisms on and within the human body that influence various physiological functions ranging from digesting food to outcompeting pathogens for resources. Also, the microbiome can affect the endocrine system, which consists of hormones that control glucose and reproduction, among other processes. This bridge, known as microbial endocrinology, has critical applications for understanding women’s health and growth disorders; this emerging area is growing, so it can address knowledge gaps in diseases like cancer and even improve other medical treatments. Written by Sam Jarada and Fozia Hassan The interactions between hormones and the microbiome, and Conclusion sections by Sam The microbiome, and Hormones and the endocrine system sections by Fozia Related articles: The gut microbiome / Dopamine and the gut / The power of probiotics / Vitamins REFERENCES “The Human Microbiome and Its Impacts on Health - PWOnlyIAS.” PWOnlyIAS , 18 Jan. 2024, pwonlyias.com/current-affairs/gut-microbiome-and-health/ . Accessed 17 Oct. 2024. Mittal, Rahul, et al. “Neurotransmitters: The Critical Modulators Regulating Gut-Brain Axis.” Journal of Cellular Physiology , vol. 232, no. 9, 10 Apr. 2017, pp. 2359–2372, www.ncbi.nlm.nih.gov/pmc/articles/PMC5772764/ , https://doi.org/10.1002/jcp.25518 . Accessed 17 Oct. 2024. Neuman, Hadar, et al. “Microbial Endocrinology: The Interplay between the Microbiota and the Endocrine System.” FEMS Microbiology Reviews , vol. 39, no. 4, 1 July 2015, pp. 509–521, academic.oup.com/femsre/article/39/4/509/2467625 , https://doi.org/10.1093/femsre/fuu010 . Hiller-Sturmhöfel S, Bartke A. The Endocrine System: An Overview. Alcohol Health and Research World. 2024;22(3):153. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC6761896/ Neuman H, Debelius JW, Knight R, Koren O. Microbial endocrinology: the interplay between the microbiota and the endocrine system. FEMS Microbiology Reviews [Internet]. 2015 Feb 19 [cited 2024 Sep 18];39(4):509–21. Available from: https://academic.oup.com/femsre/article/39/4/509/2467625?login=false Jose Antonio Santos-Marcos, Mora-Ortiz M, Tena-Sempere M, José López-Miranda, Camargo A. Interaction between gut microbiota and sex hormones and their relation to sexual dimorphism in metabolic diseases. Biology of Sex Differences. 2023 Feb 7;14(1). He S, Li H, Yu Z, Zhang F, Liang S, Liu H, et al. The Gut Microbiome and Sex Hormone-Related Diseases. Frontiers in Microbiology. 2021 Sep 28;12. Siddiqui R, Makhlouf Z, Alharbi AM, Alfahemi H, Khan NA. The Gut Microbiome and Female Health. Biology [Internet]. 2022 Nov 1;11(11):1683. Available from: https://www.mdpi.com/2079-7737/11/11/1683 Jensen E, Young JA, Jackson Z, Busken J, List EO, Ronan O’Carroll, et al. Growth Hormone Deficiency and Excess Alter the Gut Microbiome in Adult Male Mice. Endocrinology [Internet]. 2020 Feb 26 [cited 2023 Nov 9];161(4). Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7341558/ Jensen EA, Young JA, Mathes SC, List EO, Carroll RK, Kuhn J, et al. Crosstalk between the growth hormone/insulin-like growth factor-1 axis and the gut microbiome: A new frontier for microbial endocrinology. Growth Hormone & IGF Research. 2020 Aug;53-54:101333. Project Gallery