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  • STEM research and resources for students | Scientia News

    Log In Welcome to Scientia News DELIVERING INFORMATIVE CONTENT Scientia News is full of STEM blogs, articles and resources freely available across the globe for students. Browse all of our fascinating content written by students and professionals showing their passion in STEM and other sciences. ​ We hope this platform helps you discover something that inspires your curiosity, and encourages you to learn more about important topics in STEM. Meet the Official Team NAVIGATE AND CLICK THE PHOTOS BELOW TO LEARN MORE ABOUT US! To play, press and hold the enter key. To stop, release the enter key. To play, press and hold the enter key. To stop, release the enter key. To play, press and hold the enter key. To stop, release the enter key. Latest Articles 01 How does moving houses impact your well-being? 18th July 2024 02 Neuromyelitis optica- how is it different to Multiple Sclerosis? 18th July 2024 03 A perspective on well-being 18th July 2024 04 Animal ethics: the good, the bad, and the ugly? 11th July 2024 05 Tracking the heavens- Chaco Canyon, New Mexico 11th July 2024 CONTACT CONTACT US Scientia News welcomes anyone who wants to share their ideas and write for our platform. If you are interested in writing for us AND live in the UK; and/ or would like to share any ideas or feedback: Email us at scientianewsorg@gmail.com or fill in our form below and we'll get in touch ... Follow us on our socials for the latest updates. Comment, like and share! Join our mailing list below for latest site content. You can also sign up to become a site member . SUBSCRIPTION Join our mailing list to receive alerts for new articles and other site content. Be sure to check your spam/ junk folders in case emails are sent there. Email Subscribe GET IN TOUCH First Name Last Name Email Message Send Thanks for submitting!

  • Medicine Articles 2 | Scientia News

    Medicine Articles (2) This page features articles which tackle imminent health problems such as smoking, childhood obesity and depression, and pre-diabetes. The use of emojis in healthcare, anaemias, and endometriosis are also explored. You may also like: Dentistry , Biology ​ The importance of emojis in healthcare Emojis were originated by Shigetaka Kurita in 1999 COMING SOON COMING SOON COMING SOON Previous

  • Advancements in Semiconductor Laser Technology | Scientia News

    Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Advancements in Semiconductor Laser Technology What they are, uses, and future outlook Lasers have revolutionized 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 is 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 milestones 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 article: The future of semi-conductor manufacturing Project Gallery

  • Huntington's disease | Scientia News

    Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Huntington's disease A hereditary neurodegenerative disorder Huntington’s disease (HD) is a neurodegenerative disorder causing cognitive decline, behavioural difficulties, and uncontrollable movements. It is a hereditary disease that has a devastating effect on the individual’s life and unfortunately is incurable. Genetic component What may come as a surprise, is that in everyone’s genetics there are two copies (one from each parent) of the Huntingtin’s gene coding for the Huntingtin protein. This gene is coded by CAG repeats. In healthy genes, the CAG sequence is repeated between 10 and 26 times. However, if the gene is faulty, CAG repeats over 40 times resulting in a dysfunctional Huntingtin protein. The disease is autosomal dominant meaning regardless of gender, if either parent is a carrier, their child has a 50% chance of inheriting the faulty gene. REMINDER: because the gene is dominant, it means those who inherit even one copy will develop the disease Effect on the brain The faulty Huntingtin protein accumulates in cells, leading to cell death and damage to the brain. If you were to look at the brains of individuals with Huntington’s Disease, you would see a reduction in volume of the caudate and putamen. These areas are part of the striatum, which is a subdivision of the basal ganglia, involved in fine tuning our voluntary movements, i.e., reaching out to grab a cup. As the disease progresses, this atrophy can extend to other areas of the brain including the thalamus, frontal lobe, and cerebellum. Symptoms The symptoms normally manifest in three categories: motor, cognitive and psychiatric. We know that the basal ganglia is involved in our voluntary movement, so the damage causes one of the most visible symptoms in HD- uncontrollable and jerky movements. Cognitive symptoms include personality changes, difficulties with planning and attention. There can also be impairments to how those with HD recognise emotions- all these symptoms can interact to make social interaction more difficult. Finally, the psychiatric symptoms often seen include irritability and aggression, depression, anxiety, and apathy. Impact on life and family At the age when diagnosis usually occurs (around 30 years old), patients are often buying houses, getting married and either having children or deciding to start a family. The diagnosis may change peoples outlook on having children and can put a great psychological burden on them if they have unknowingly passed it along to those already born. Diagnosis also brings consequences to seemingly mundane, but incredibly important issues such as gaining life insurance, with some companies not covering individuals with an official diagnosis. Subsequently this makes life harder for their families, as the patient will eventually be unable to work and there could be associated costs with the need for care facilities as the disease progresses. Unfortunately, this is a progressive neurodegenerative condition with no cure. The only treatment options available at present, are interventions which aim to alleviate the patients’ symptoms. Whilst these treatments will reduce the motor and psychiatric symptoms, they cannot stop the progression of Huntington’s disease. We have only scratched the surface on the impact Huntington’s disease has on a patient and their families. It is so important to understand ways in which everyone that is affected can be best supported during the disease progression, to give all those involved a better quality of life. By Alice Jayne Greenan Project Gallery

  • A comprehensive guide to the Relative Strength Index (RSI) | Scientia News

    Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link A comprehensive guide to the Relative Strength Index (RSI) The maths behind trading In this piece, we will delve into the essential concepts surrounding the Relative Strength Index (RSI). The RSI serves as a gauge for assessing the strength of price momentum and offers insights into whether a particular stock is in an overbought or oversold condition. Throughout this exploration, we will demystify the underlying calculations of RSI, explore its significance in evaluating market momentum, and unveil its practical applications for traders. From discerning opportune moments to buy or sell based on RSI values to identifying potential shifts in market trends, we will unravel the mathematical intricacies that underpin this critical trading indicator. Please note that none of the below content should be used as financial advice, but for educational purposes only. This article does not recommend that investors base their decisions on technical analysis alone. As indicated in the name, RSI measures the strength of a stock's momentum and can be used to show when a stock can be considered over- or under-bought, allowing us to make a more informed decision as to whether we should enter a position or hold off until a bit longer. It’s all very well and good to know that ‘you should buy when RSI is under 30 and sell when RSI is over 70' , but in this article, I will attempt to explain why this is the case and what RSI is really measuring. The calculations The relative strength index is an index of the relative strength of momentum in a market. This means that its values range from 0 to 100 and are simply a normalised relative strength. But what is the relative strength of momentum? Initial Average Gain = Sum of gains over the past 14 days / 14 Initial Average Loss = Sum of losses over the past 14 days / 14 Relative strength is the ratio of higher closes to lower closes. Over a fixed period of usually 14 days (but sometimes 21), we measure how much the price of the stock has increased in each trading day and find the mean average between them. We then repeat and do the same to find the average loss. The subsequent average gains and losses can then be calculated: Average Gain = [(Previous Avg. Gain * 13) + Current Day's Gain] / 14 Average Loss = [(Previous Avg. Loss * 13) + Current Day's Loss] / 14 With this, we can now calculate relative strength! Therefore, if our stock gained more than it lost in the past 14 days, then our RS value would be >1. On the other hand, if we lost more than we gained, then our RS value would be <1. Relative strength tells us whether buyers or sellers are in control of the price. If buyers were in control, then the average gain would be greater than the average loss, so the relative strength would be greater than 1. In a bearish market, if this begins to happen, we can say that there is an increase in buyers’ momentum; the momentum is strengthening. We can normalise relative strength into an index using the following equation: Relative Strength=Average Gain / Average Loss Traders then use the RSI in combination with other techniques to assess whether to buy or sell. When a market is ranging, which means that price is bouncing between support and resistance (has the same highs and lows for a period), we can use the RSI to see when we may be entering a trend. When the RSI is reaching 70, it is an indication that the price is being overbought, and in a ranging market, there is likely to be a correction and the price will fall so that the RSI stays at around 50. The opposite is likely to happen when the RSI dips to 30. Price action is deemed to be extreme, and a correction is likely. It should, however, be noted that this type of behaviour is only likely in assets presenting mean-reversion characteristics. In a trending market, RSI can be used to indicate a possible change in momentum. If prices are falling and the RSI reaches a low and then, a few days later, it reaches a higher low (therefore, the low is not as low as the first), it indicates a possible change in momentum; we say there is a bullish divergence. Divergences are rare when a stock is in a long-term trend but is nonetheless a powerful indicator. In conclusion, the relative strength index aims to describe changes in momentum in price action through analysing and comparing previous day's highs and lows. From this, a value is generated, and at the extremes, a change in momentum may take place. RSI is not supposed to be predictive but is very helpful in confirming trends indicated by other techniques. Written by George Chant Project Gallery

  • Advances in mass spectrometry technology | Scientia News

    Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Advances in mass spectrometry technology Pushing the boundaries of analytical chemistry In the rapidly evolving field of analytical chemistry, recent technological innovations in mass spectrometry have revolutionised the analysis and characterisation of molecules. These advancements, including high-resolution mass analysers, ion mobility spectrometry (IMS), and ambient ionisation techniques, are pushing the boundaries of what can be achieved in chemical analysis. Mass spectrometry is a powerful analytical technique that provides qualitative and quantitative information on an analyte. It is useful for measuring the mass-to-charge ratio (m/z) of one or more molecules present in a sample. The process consists of: Inlet - Allows the analyte to be connected to the mass spectrometre (MS). Could be direct inlet or gas chromotography (GC) / liquid chromatography (LC) to allow some separation before MS Ion source - Ensures that the analyte is ionised (i.e. carries a net charge) there are various types of ion sources depending on the analyte Analysers - Brings about a change in the velocity/trajectory of an ion from which the ions m/z can be determined i.e. characterises rate/velocity of ion. Multiple analysers are in tandem and different analysers can be combined to allow greater scope for analysis. A detection system is also required to amplify and measure ion signals. Analysers and detectors need to be held under low pressure - near vacuum. Detector - collects charge signals from ion beams. The computer then detects a spectrum. The electronic signals from the ions are then digitised to produce a mass spectrum of the analyte. High-resolution mass analysers One of the most significant breakthroughs in mass spectrometry is the development of high-resolution mass analysers. These instruments can differentiate between ions with extremely close mass-to-charge ratios, providing unprecedented levels of accuracy and specificity in compound identification. High-resolution mass spectrometry enables scientists to resolve complex mixtures and detect trace components with exceptional sensitivity, making it invaluable in fields such as metabolomics, environmental analysis, and drug discovery. Ion Mobility Spectrometry (IMS) Ion mobility spectrometry is another cutting-edge technology that enhances the capabilities of mass spectrometry. IMS separates ions based on their size, shape, and charge in the gas phase, providing an additional dimension of separation before mass analysis. This technique improves the resolution of complex samples, particularly for isomeric compounds that are challenging to distinguish using conventional methods. IMS coupled with mass spectrometry is widely applied in metabolomics, proteomics, and lipidomics research, enabling deeper insights into molecular structures and interactions. Ambient ionisation techniques Traditional mass spectrometry methods often require extensive sample preparation and ionisation processes in controlled laboratory environments. Ambient ionisation techniques have transformed this paradigm by enabling direct analysis of samples in their native states, including solids, liquids, and gases, without prior extraction or purification steps. Techniques such as desorption electrospray ionisation (DESI) and direct analysis in real-time (DART) have expanded the scope of mass spectrometry applications to fields like clinical diagnostics, food safety, and forensic analysis. Ambient ionisation allows for rapid, on-site measurements with minimal sample handling, revolutionising point-of-care testing and field analysis. In conclusion, the continuous evolution of mass spectrometry technology is reshaping the landscape of analytical chemistry. These innovations not only empower researchers to explore new realms of chemical analysis but also facilitate applications in areas such as precision medicine, environmental monitoring, and materials science. As these technologies continue to advance, the future holds even greater promise for pushing the boundaries of analytical chemistry and unlocking the mysteries of the molecular world. Written by Anam Ahmed Project Gallery

  • The dopamine connection | Scientia News

    Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link The dopamine connection How your gut influences your mood and behaviour Introduction to dopamine Dopamine is a neurotransmitter derived from an amino acid called phenylalanine, which must be obtained through the diet, through foods such as fish, meat, dairy and more. Dopamine is produced and released by dopaminergic neurons in the central nervous system and can be found in different brain regions. The neurotransmitter acts via two mechanisms: wiring transmission and volume transmission. In wiring transmission, dopamine is released to the synaptic cleft and acts on postsynaptic dopamine receptors. In volume transmission, extracellular dopamine arrives at neurons other than postsynaptic ones. Through methods such as diffusion, dopamine then reaches receptors in other neurons that are not in direct contact with the cell that has released the neurotransmitter. In both mechanisms, dopamine binds to the receptors, transmitting signals between neurons and affecting mood and behaviour. The link between dopamine and gut health Dopamine has been known to result in positive emotions, including pleasure, satisfaction and motivation, which can be influenced by gut health. Therefore, what you eat and other factors, including motivation, could impact your mood and behaviour. This was proven by a study (Hamamah et al., 2022), which looked at the bidirectional gut-brain connection. The study found that gut microbiota was important in maintaining the concentrations of dopamine via the gut-brain connection, also known as the gut microbiota-brain axis or vagal gut-to-brain axis. This is the communication pathway between the gut microbiota and the brain facilitated by the vagus nerve, and it is important in the neuronal reward pathway, which regulates motivational and emotional states. Activating the vagal gut-to-brain axis, which leads to dopamine release, suggests that modulating dopamine levels could be a potential treatment approach for dopamine-related disorders. Some examples of gut microbiota include Prevotella, Bacteroides, Lactobacillus, Bifidobacterium, Clostridium, Enterococcus, and Ruminococcus , and they can affect dopamine by modulating dopaminergic activity. These gut microbiota are able to produce neurotransmitters, including dopamine, and their functions and bioavailability in the central nervous system and periphery are influenced by the gut-brain axis. Gut dysbiosis is the disturbance of the healthy intestinal flora, and it can lead to dopamine-related disorders, including Parkinson's disease, ADHD, depression, anxiety, and autism. Gut microbes that produce butyrate, a short-chain fatty acid, positively impact dopamine and contribute to reducing symptoms and effects seen in neurodegenerative disorders. Dopamine as a treatment It is important to understand the link between dopamine and gut health, as this could provide information about new therapeutic targets and improve current methods that have been used to prevent and restore deficiencies in dopamine function in different disorders. Most cells in the immune system contain dopamine receptors, allowing processes such as antigen presentation, T-cell activation, and inflammation to be regulated. Further research into this could open up a new possibility for dopamine to be used as a medication to treat diseases by changing the activity of dopamine receptors. Therefore, dopamine is important in various physiological processes, both in the central nervous and immune systems. For example, studies have shown that schizophrenia can be treated with antipsychotic medications which target dopamine neurotransmission. In addition, schizophrenia has also been treated by targeting the dysregulation (decreasing the amount) of dopamine transmission. Studies have shown promising results regarding dopamine being used as a form of treatment. Nevertheless, further research is needed to understand the interactions between dopamine, motivation and gut health and explore how this knowledge can be used to create medications to treat conditions. Conclusion The bidirectional gut-brain connection shows the importance of gut microbiota in controlling dopamine levels. This connection influences mood and behaviour but also has the potential to lead to new and innovative dopamine-targeted treatments being developed (for conditions including dopamine-related disorders). For example, scientists could target and manipulate dopamine receptors in the immune system to regulate the above mentioned processes: antigen presentation, T-cell activation, and inflammation. While current research has shown some promising results, further investigations are needed to better comprehend the connection between gut health and dopamine levels. Nevertheless, through consistent studies, scientists can gain a deeper understanding of this mechanism to see how changes in gut microbiota could affect dopamine regulation and influence mood and behaviour. Written by Naoshin Haque Related articles: the gut microbiome / Crohn's disease Project Gallery

  • Genetically-engineered bacteria break down plastic in saltwater | Scientia News

    Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Genetically-engineered bacteria break down plastic in saltwater Unlocking the potential to tackle plastic pollution in oceans Groundbreaking discovery in the fight against plastic pollution North Carolina State University researchers have made a groundbreaking discovery in the fight against plastic pollution in marine environments. They have successfully genetically engineered a marine microorganism capable of breaking down polyethylene terephthalate (PET), a commonly used plastic found in water bottles and clothing, contributing to the growing problem of ocean microplastic pollution. Introducing foreign enzymes to V. natriegens The modified organism, created by incorporating genes from the bacterium Ideonella sakaiensis into the genome of Vibrio natriegens , can effectively degrade PET in saltwater conditions. This achievement marks the first time foreign enzymes have been successfully expressed on the surface of V. natriegens cells, making it a significant scientific breakthrough. PET microplastics pose a significant challenge in marine ecosystems, and current methods of removing them, such as extracting and disposing of them in landfills, are not sustainable. The researchers behind this study aim to find a more environmentally friendly solution by breaking down PET into reusable products, like thermoformed packaging (takeaway cartons) or textiles (clothing, duvets, pillows, carpeting). The team worked with two bacteria species, V. natriegens and I. sakaiensis . V. natriegens , known for its rapid reproduction in saltwater, served as the host organism, while I. sakaiensis provided the enzymes necessary for PET degradation. The researchers first rinsed the plastics collected from the ocean to remove high-concentration salts before initiating the plastic degradation process. Challenges ahead While this breakthrough is a significant step forward, three key challenges are still ahead. The researchers aim to incorporate the DNA responsible for enzyme production directly into the genome of V. natriegens to enhance stability. Because DNA is the genetic material responsible for the production of enzymes, and enzymes are proteins that are responsible for carrying out various chemical reactions in the body, by incorporating the DNA responsible for enzyme production into the genome of V. natriegens , the researchers can enhance the stability of the enzyme production. Thus, this DNA is essential for producing the enzymes necessary for PET degradation, as it contains the genetic information vital for encoding the proteins needed for PET breakdown. Additionally, the research team plans to modify V. natriegens further to feed on the byproducts generated during PET degradation. Lastly, they seek to engineer V. natriegens to produce a desirable end product from PET, such as a molecule that can be utilised in the chemical industry. Collaboration with industry groups Collaboration with industry groups is also crucial in determining the market demand for the molecules that V. natriegens can produce. The researchers are open to working with industry partners to explore the vast production scale and identify the most desirable molecules for commercial use. By introducing the genes responsible for PET degradation into V. natriegens using a plasmid, the researchers successfully induced the production of enzymes on the surface of the bacterial cells. The modified V. natriegens demonstrated its ability to break down PET microplastics in saltwater, providing a practical and economically feasible solution for addressing plastic pollution in marine environments. This research represents a significant advancement in the field, as it is the first time that V. natriegens has been genetically engineered to express foreign enzymes on its cell surface. This breakthrough opens up possibilities for further modifications, such as incorporating the DNA from I. sakaiensis directly into the genome of V. natriegens to make the production of plastic-degrading enzymes a more stable feature of the organism. The researchers aim to modify V. natriegens to feed on the byproducts produced during the breakdown of PET and create a desirable end product for the chemical industry. The researchers are open to collaborating with industry groups to identify the most desirable molecules to be engineered into V. natriegens for production. This groundbreaking research, published in the AIChE Journal with the support of the National Science Foundation under grant 2029327, paves the way for developing more efficient and sustainable methods for addressing plastic pollution in saltwater environments. Conclusion The research has made a breakthrough in the fight against plastic pollution in marine environments. By incorporating genes from the bacterium I. sakaiensis into the genome of V. natriegens , they created a genetically modified marine microorganism capable of breaking down PET. This achievement provides a practical and economically feasible solution to address plastic pollution in aquatic ecosystems. The researchers are now looking into further modifications to the organism to enable it to feed on byproducts and to produce a desirable end product that can be used in the chemical industry. This research highlights the potential of genetic engineering to create sustainable solutions to the growing problem of plastic pollution. Written by Sara Maria Majernikova Project Gallery

  • The Genetics of Ageing and Longevity | Scientia News

    Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link The Genetics of Ageing and Longevity A well-studied longevity gene is SIRT1 Ageing is a natural process inherent to all living organisms. Yet, its mechanisms remain somewhat enigmatic. While lifestyle factors undoubtedly influence longevity, recent advancements in genetic research have revealed the influence of our genomes on ageing. Through understanding these influences, we can unlock further knowledge on longevity, which can aid us in developing interventions to promote healthy ageing. This article delves into the world of ageing and longevity genetics and how we can use this understanding to our benefit. Longevity genes A number of longevity genes, such as APOE , FOXO3 , and CETP, have been identified. These genes influence various biological processes, including cellular repair, metabolism, and stress response mechanisms. A well-studied longevity gene is SIRT1 . Located on chromosome 10, SIRT1 encodes sirtuin 1, a histone deacetylase, transcription factor, and cofactor. Its roles include protecting cells against oxidative stress, regulating glucose and lipid metabolism, and promoting DNA repair and stability via deacetylation. Sirtuins are an evolutionarily conserved mediator of longevity in many organisms. One study looked at mice with knocked-out SIRT1 ; these mice had significantly lower lifespans when compared with WT mice1. The protective effects of SIRT1 are thought to be due to deacetylating p53, which promotes cell death2. SIRT1 also stimulates the cytoprotective and stress-resistance gene activator FoxO1A (see Figure 1 ), which upregulates catalase activity to prevent oxidative stress3. Genome-wide association studies (GWAS) have identified several genetic variants associated with ageing and age-related diseases. Such variants influence diverse aspects of ageing, such as cellular senescence, inflammation, and mitochondrial function. For example, certain polymorphisms in APOE are associated with an increased risk of age-related conditions like Alzheimer's and Parkinson’s disease4. These genes have a cumulative effect on the longevity of an organism. Epigenetics of ageing Epigenetic modifications, such as histone modifications and chromatin remodelling, regulate gene expression patterns without altering the DNA sequence. Studies have shown that epigenetic alterations accumulate with age and contribute to age-related changes in gene expression and cellular function. For example, DNA methylation is downregulated in human fibroblasts during ageing. Furthermore, ageing correlates with decreased nucleosome occupancy in human fibroblasts, thereby increasing the expression of genes unoccupied by nucleosomes. One specific marker of ageing in metazoans is H3K4me3, indicating the trimethylation of lysine 4 on histone 3; in fact, H3K4me3 demethylation extends lifespan. Similarly, H3K27me3 is also a marker of biological age. By using these markers as an epigenetic clock, we can predict biological age using molecular genetic techniques. As a rule of thumb, genome-wide hypomethylation and CpG island hypermethylation correlate with ageing, although this effect is tissue-specific5. Telomeres are regions of repetitive DNA at the terminal ends of linear chromosomes. Telomeres become shorter every time a cell divides (see Figure 2 ), and eventually, this can hinder their function of protecting the ends of chromosomes. As a result, cells have complex mechanisms in place to prevent telomere degradation. One of these is the enzyme telomerase, which maintains telomere length by adding G-rich DNA sequences. Another mechanism is the shelterin complex, which binds to ‘TTAGGG’ telomeric repeats to prevent degradation. Two major components of the shelterin complex are TRF1 and TRF2, which bind telomeric DNA. They are regulated by the chromatin remodelling enzyme BRM-SWI/SNF, which has been shown to be crucial in promoting genomic stability, preventing cell apoptosis, and maintaining telomeric integrity. BRM-SWI/SNF regulates TRF1/2, thereby, regulating the shelterin complex, by remodelling the TRF1/2 promoter region to convert it to euchromatin and increase transcription. BRM-SWI/SNF inactivating mutations have been shown to contribute to cancer and cellular ageing through telomere degradation6. Together, the mechanisms cells have in place to protect telomeres provide protection against cancer as well as cellular ageing. Future of anti-ageing drugs Anti-ageing drugs are big business in the biotechnology and cosmetics sector. For example, senolytics are compounds that decrease the number of senescent cells in an individual. Senescent cells are those that have permanently exited the cell cycle and now secrete pro-inflammatory molecules (see Figure 3); they are a major cause of cellular and organismal ageing. Senolytic drugs aim to provide anti-ageing benefits to an individual, whereby senescent cells are removed, therefore, decreasing inflammation. Currently, researchers are certain that removing senescent cells would have an anti-ageing effect, although senolytic drugs currently on the market are understudied, and so their side effects are unknown. Speculative drugs could include those that enhance telomerase or SIRT1 activity. Evidently, ageing is not purely determined by lifestyle and environmental factors alone but also by genetics. While longevity genes are hereditary, epigenetic modifications may be influenced by external factors. Therefore, we can attribute the complex interplay between various external factors and an individual’s genome to understanding the role of genetics in ageing. Perhaps we will see a new wave of anti-ageing treatments in the coming years, developed on the genetics of ageing. Written by Malintha Hewa Batage Related article: An introduction to epigenetics REFERENCES Cilic, U et al., (2015) ‘A Remarkable Age-Related Increase in SIRT1 Protein Expression against Oxidative Stress in Elderly: SIRT1 Gene Variants and Longevity in Human’, PLoS One , 10(3). Alcendor, R et al., (2004) ‘Silent information regulator 2alpha, a longevity factor and class III histone deacetylase, is an essential endogenous apoptosis inhibitor in cardiac myocytes’, Circulation Research , 95(10):971-80. Alcendor, R et al., (2007) ‘Sirt1 regulates aging and resistance to oxidative stress in the heart’, Circulation Research , 100(10):1512-21. Yin, Y & Wang, Z, (2018) ‘ApoE and Neurodegenerative Diseases in Aging’, Advances in Experimental Medicine and Biology , 1086:77-92. Wang, K et al., (2022) ‘Epigenetic regulation of aging: implications for interventions of aging and diseases’, Signal Transduction and Targeted Therapy , 7(1):374. Images made using BioRender. Project Gallery

  • Anaemia of chronic disease | Scientia News

    Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Anaemia of chronic disease Second most common anaemia This article is no. 3 of the anaemia series. Next article: sideroblastic anaemia Pathogenesis The second most prevalent anaemia is anaemia of chronic disease (ACD), it is more often seen alongside chronic infections or malignancies, other causes include infections, autoimmune diseases, and transplant rejection. The pathogenesis of the condition is greatly lead by the effectiveness of the immune system, the immune response to tumour cells and pathogens is to remove and deny access to iron, which is needed to thrive. The processes are mainly thought to be mediated through cytokines such as TNF, IL-6s and IFN as well as the acute phase protein hepcidin. IL-6 is a very powerful cytokine in that it can inhibit erythropoiesis through the downregulation of gene expression; SLC4a1 reducing haemoglobin production, it increases ferratin production whilst inhibiting TNF-α, it upregulates DMT-1 which is a protein (transmembrane) involved in iron uptake in macrophages and it upregulates the production of hepcidin. Hepicidin Hepcidin is a peptide hormone, 25 amino acid chain protein, derived mainly from hepatic cells its synthesis is induced as a response to iron overload or inflammation, its presence crucial in the diagnosis of ACD. IL-6 induces hepcidin release from hepatocytes, upregulation causes the transport protein (ferroportin) degradation inhibiting iron absorption in duodenum enterocytes and macrophage recycling via upregulation of dMT-1 and mobilization of stored iron resulting in low iron plasma. Clinical presentation A patient with ACD may have low haemoglobin (Hb) and the reticulocyte index (new RBC) count may be reduced also, this is a common feature of an iron deficient anaemia. A blood film may help diagnose the underlying condition, but the red cell morphology varies greatly, less than half can be microcytic or hypochromic. Iron studies are what helps ACD stand out from the other anaemias, raised IL-6, hepcidin and ferratin are the key markers; the presence of iron results with raised ferratin and iron will be seen if a blood film is stained correctly. There may also be reduced serum iron, % saturation and TIBC. Should erythrocyte sedimentation rates be high Rouleaux’s may be seen, which are aggregations of RBC. Conclusion The most efficient way to diagnose an anaemia is through serum biomarkers in a FBC and iron studies. Hepcidin and other chemical markers play a key role in the diagnosis of ACD. Iron studies help to paint a clearer picture when diagnosing anaemias but should be supported with a medical history alongside a clinical examination, as comorbidities may influence chronic inflammatory markers. By Lauren Kelly Project Gallery

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