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The human race has witnessed ten influenza pandemics over the course of 300 years. COVID-19, the most recent, killed approximately 6.9 million people and infected nearly 757 million. Go Back Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link The world vs the next pandemic Last updated: 18/11/24 Published: 25/03/23 The human race has witnessed ten influenza pandemics over the course of 300 years. COVID-19, the most recent, killed approximately 6.9 million people and infected nearly 757 million. Though seemingly quite large, the number of deaths caused by the coronavirus is still comparatively fewer than the pandemics of the past, which have killed around 50–100 million people globally. These large numbers may seem like statistics from a century ago, but many scientists predict the same-scale destruction with future pandemics, heightening the concern about how prepared we are when the next big outbreak strikes. It is impossible to know when the next pandemic will hit or the number of casualties it will bring. The only certainty is that it cannot be avoided, which raises the question of how to mitigate the impact and reduce the effectiveness of large-scale losses. During the COVID-19 outbreak, we observed that preventive measures such as social distancing and face coverings could intervene in viral transmission to some degree. Additionally, strategies like complete lockdown, isolation and timely treatment can help in the containment and recovery of those already infected. These measures, however, can only be taken once the threat is detected promptly before infecting a larger population. To prevent an infection from becoming an outbreak, strategies that focus on the source of the disease can prove to be highly advantageous. Preventive measures may include: ● monitoring the mobilisation of wildlife that potentially carries harmful pathogens ● studying the interactions between different species in wildlife ● surveillance of the domestic and international markets for wildlife trade and strict imposition of biosecurity laws. Additionally, an effort needs to be made for sharing the generated data with global laboratories to promote scientific collaboration. Once the threat is identified, quick decision-making using the correct precautions needs to take place. Simultaneously, investments in research sectors promoting mRNA vaccine developments, novel drug treatments, and emerging technological advances need to be increased. In conclusion, the strategies for the management of the next pandemic need to operate on a multi-level governance with optimal coordination between different institutions involved in crisis management. There is a constant threat of pandemics looming over the world. The outbreak is inevitable, but its effect solely depends on the preparedness and response of the governmental bodies and global health institutions. Is it going to be a hurricane of destruction, or will it just pass by like a gush of wind? Only time will tell. Written by Navnidhi Sharma Related articles: Diabetes mellitus as an epidemic / Are pandemics becoming less severe? REFERENCES Coccia, M. (2021). Pandemic Prevention: Lessons from COVID-19. Encyclopedia, 1(2), 433–444. https://doi.org/10.3390/encyclopedia1020036 Cockerham, W. C., & Cockerham, G. B. (2021). The COVID-19 reader: the science and what it says about the social. Routledge. Frieden, T. R., Buissonnière, M., & McClelland, A. (2021). The world must prepare now for the next pandemic. BMJ Global Health, 6(3), e005184. https://doi.org/10.1136/bmjgh-2021-005184 Garrett, L. (2005). The Next Pandemic. Foreign Af airs, 84, 3. https://heinonline.org/HOL/LandingPage?handle=hein.journals/fora84&div=61&id=&page= WORLD HEALTH ORGANISATION. (2022). WHO Coronavirus (COVID-19) Dashboard. Covid19.Who. int. https://covid19.who.int/?mapFilter=deaths World Economic Forum. (2021, November 30). COVID-19: How much will it cost to prepare the world for the next pandemic? World Economic Forum. https://www.weforum.org/agenda/2021/11/preparing-for-next-pandemic-covid-19

To begin, there was the Humoral Theory, which looked at how disease was caused by gaps in fluids/humours which were: blood, yellow bile, black bile and phlegm, which equated to the elements of air, fire, earth and water respectively. The imbalance can come from habits like overeating Go back Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Key historical events and theories in public health Last updated: 17/11/24 Published: 10/02/23 Introduction Now more than ever, public health has become crucial, which looks at promoting health and preventing disease within a society. There have been numerous events and concepts that have helped shape our current health systems today because without them, it is possible that our health systems would not have advanced without previous knowledge to evolve from. This article will focus on certain key events and concepts. Humoral Theory (Ancient Greek and Roman times) To begin, there was the Humoral Theory, which looked at how disease was caused by gaps in fluids/humours which were: blood, yellow bile, black bile and phlegm, which equated to the elements of air, fire, earth and water respectively. The imbalance can come from habits like overeating and too little/much exercise or external factors such as the weather. This theory was thought to have originated from the Hippocratic Corpus, a compilation of 60 medical documents written during the Ancient Greek era by Hippocrates. Although this theory as we know now is flawed, it did provide a foundational understanding of the human body and was utilised in public health for centuries before being subsequently discredited for the Germ Theory established during the mid-19th century. Miasma Theory (Ancient Greek era to the 19th century) Another theory replaced by Germ Theory was the Miasma theory, which stated that diseases like the plague and cholera were spread due to toxic vapours from the ground/decomposing matter. This theory along with the Humoral theory was accepted for thousands of years since the Ancient Greek era. With regards to the cholera outbreaks in the Victorian era, John Snow’s theory of polluted water causing cholera was initially not accepted by the scientific community during his death in 1858. Eventually though, his theory became accepted when Joseph Bazalgette worked to fix London’s sewage to prevent more deaths by cholera. This event with the Germ Theory led to Miasma and Humoral theories to be disproved, although they provided foundational understanding of how diseases spread. The discovery of vaccines (late 18th century) Aside from theories such as the four humors from above, there were concepts or discoveries that advanced public health measures such as vaccination, which eradicated smallpox and is still used today to prevent the severity of diseases such as COVID-19, influenza and polio. The origins of successful vaccines could be traced back to Edward Jenner who in 1796, retrieved samples from cowpox lesions from a milkmaid because he noticed that contracting cowpox protected against smallpox. With this in mind, he inoculated an 8 year old boy and after this, the boy developed mild symptoms, but then became better. Without this event, it is likely that the human population would significantly decrease as there is more vulnerability to infectious diseases and public health systems being weaker or less stable. Image of a COVID-19 injection. Germ Theory (19th century) As for current scientific theories relating to public health, there is the widely accepted Germ Theory by Robert Koch during the 19th century in the 1860s, stating that microorganisms can cause diseases. He established this theory by looking at cow’s blood through a microscope to see that they died from anthrax and observed rod-shaped bacteria with his hypothesis that they caused anthrax. To test this, he infected mice with blood from the cows and the mice also developed anthrax. After these tests, he developed postulates and even though there are limitations to his postulates at the time like not taking into account prions or that certain bacteria do not satisfy the postulates, they are vital to the field of microbiology, in turn making them important to public health. The establishment of modern epidemiology (19th century) Another key concept for public health is epidemiology, which is the study of the factors as well as distribution of chronic and infectious diseases within populations. One of epidemiology’s key figures is John Snow, who explored the cholera epidemics in London 1854, where he discovered that contaminated water from specific water pumps was the source of the outbreaks. Moreover, John Snow’s work on cholera earned him the title of the “father of modern epidemiology” along with his work providing a basic understanding of cholera. Therefore, this event among others has paved the way for health systems to become more robust in controlling outbreaks such as influenza and measles. Conclusion Looking at the key events above, it is evident that each of them has played an essential role in building the public health systems today through the contributions of the scientists. However, public health, like any other science, is constantly evolving and there are still more future advancements to look forward to that can increase health knowledge. Written by Sam Jarada Related articles: Are pandemics becoming less severe? / Rare zoonotic diseases / How bioinformatics helped with COVID-19 vaccines REFERENCES Lagay F. The Legacy of Humoral Medicine. AMA Journal of Ethics. 2002 Jul 1;4(7). Earle R. Humoralism and the colonial body. Earle R, editor. Cambridge University Press. Cambridge: Cambridge University Press; 2012. Halliday S. Death and miasma in Victorian London: an obstinate belief. BMJ. 2001 Dec 22;323(7327):1469–71. Riedel S. Edward Jenner and the history of smallpox and vaccination. Proceedings (Baylor University Medical Center). 2005 Jan 18;18(1):21. National Research Council (US) Committee to Update Science, Medicine, and Animals. A Theory of Germs. Nih.gov. National Academies Press (US); 2017. Sagar Aryal. Robert Koch and Koch’s Postulates. Microbiology Notes. 2022. Tulchinsky TH. John Snow, Cholera, the Broad Street Pump; Waterborne Diseases Then and Now. National Library of Medicine. Elsevier; 2018. p. 77–99.

An introductory and comprehensive review of complex diseases and their environmental influences. Using schizophrenia as an example, we are interested in exploring one of the biggest questions that underlie complex diseases. Go Back Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link The environment on complex diseases: schizophrenia Last updated: 18/11/24 Published: 08/05/23 An introductory and comprehensive review of complex diseases and their environmental influences. Using schizophrenia as an example, we are interested in exploring one of the biggest questions that underlie complex diseases. Introduction: Not Exactly a Yes or No Question Many things in science revolve around questions. It is remarkable to find the number of questions left for scientists to answer or those that will remain unanswered. Indeed, one of the most daunting tasks for any scientist would be to see through every detail of a piece of information, even if everyone has seen it, but with different sets of lenses and asking different sets of questions. After all, “why did the apple fall from its tree?”. However, asking questions is one thing. Finding answers and, more importantly, the evidence or proof that supports them does not always yield conclusive results. Nevertheless, perhaps some findings may shine a new light on a previously unanswered question. We can categorise the study of genetics into two questions: “What happens if everything goes well?” and “What happens if it goes wrong?”. Whilst there are virtually limitless potential causes of any genetic disease, most genetic diseases are known to be heritable. A mutation in one gene that causes a disease can be inherited from the parents to their offspring. Often, genetic diseases are associated with a fault in one gene, known as a single-gene disorder, with notorious names including Huntington’s disease, cystic fibrosis, sickle cell anaemia, and familial hypercholesterolaemia. These diseases have different mechanisms, and the causes are also diverse. But all these diseases have one thing in common: they are all caused by a mutation or fault in one gene, and inheriting any specific genes may lead to disease development. In other words, “either you have it, or you do not”. The role of DNA and mutations in complex diseases. Image/ craiyon.com Multifactorial or complex diseases are a classification geneticists give to diseases caused by factors, faults or mutations in more than one gene. In other words, a polygenic disease. As a result, the research, diagnosis, and identification of complex diseases may not always produce a clear “black-and-white” conclusion. Furthermore, complex diseases make up most non-infectious diseases known. The diseases associated with leading causes of mortality are, in their respective ways, complex. Household names include heart diseases, Alzheimer’s and dementia, cancer, diabetes, and stroke. All of these diseases may employ many mechanisms of action, involving multiple risk factors instead of direct cause and effect, using environmental and genetic interactions or factors to their advantage, and in contrast to single-gene disorders, do not always follow clear or specific patterns of inheritance and always involve more than one problematic genes before the complete symptoms manifest. For these reasons, complex diseases are infamously more common and even more challenging to study and treat than many other non-infectious diseases. No longer the easy “yes or no” question. The Complex Disease Conundrum: Schizophrenia Here we look at the case of a particularly infamous and, arguably, notorious complex disease, schizophrenia (SCZ). SCZ is a severely debilitating and chronic neurodevelopmental disorder that affects around 1% of the world’s population. Like many other complex diseases, SCZ is highly polygenic. The NHS characterise SCZ as a “disease that tends to run in families, but no single gene is known to be directly responsible…having these genes does not necessarily mean one will develop SCZ”. As previously mentioned, many intricate factors are at play behind complex diseases. In contrast, there is neither a single known cause for SCZ nor a cure. Additionally, despite its discovery a century ago, SCZ is arguably not well understood, giving a clue to the sophisticated mechanisms that underlie SCZ. To further illustrate how such complexities may pose a challenge to future medical treatments, we shall consider a conundrum that diseases like SCZ may impose. The highly elaborate nature of complex diseases means that it is impossible to predict disease outcomes or inheritance with absolute certainty nor rule out potential specific causes of diseases. One of the most crucial aspects of research on complex diseases is their genetic architecture, just as a house is arguably only as good as its blueprint. Therefore, a fundamental understanding of the genes behind diseases can lead to a better knowledge of diseases’ pathogenesis, epidemiology, and potential drug target, and hopefully, one day bridge our current healthcare with predictive and personalised medicine. However, as mentioned by the NHS, one of the intricacies behind SCZ is that possessing variants of diseased genes does not translate to certainty in disease development or symptom manifestation. Our conundrum, and perhaps the biggest question on complex diseases like SCZ is: “Why, even when an individual possesses characteristic genes of a complex disease, they may not necessarily exhibit symptoms or have the disease?”. The enigma surrounding complex diseases lies in the elegant interactions between our genes, the blueprint of life, and “everything else”. Understanding the interplay of factors behind complex diseases may finally explain many of the intricacies behind diseases like SCZ. Genes and Environment: an Obvious Interaction? The gene-environment important implications on complex disease development were demonstrated using twin studies. A twin study, as its name suggests, is the study of twins by their similarities, differences, and many other traits that twins may exhibit to provide clues to the influences of genetic and external factors. Monozygotic (MZ) twins each share the same genome and, therefore, are genetically identical. Therefore, if one twin shows a phenotype, the other twin would theoretically also have said genes and should exhibit the corresponding trait. Experimentally, we calculate the concordance rate, which means the probability of both twins expressing a phenotype or characteristic, given that one twin has said characteristic. Furthermore, the heritability score may be mathematically approximated using MZ concordance and the concordance between dizygotic twins (twins that share around half a genome). These studies are and have been particularly useful in demonstrating the exact implications genetic factors have on phenotypes and how the expression of traits may have been influenced by confounding factors. In the case of SCZ, scientists have seen, over decades, a relatively low concordance rate but high heritability score. A recent study (published in 2018) through the Danish SCZ research cohort involved the analysis of around 31,500 twins born between the years 1951 and 2000, where researchers reported a concordance rate of 33% and estimated heritability score of 79%, with other older studies reporting a concordance rate up to and around 50%. The percentages suggest that SCZ is likely to be passed down. In other words, a genetically identical twin only has approximately 1 in 2 risks of also developing symptoms of SCZ if its opposite twin also displays SCZ. The scientists concluded that although genetic predisposition significantly affects one’s susceptibility or vulnerability against SCZ, it is not the single cause of SCZ. Demographically, there have been studies that directly link environmental risks to SCZ. Some risk factors, such as famines and malnutrition, are more evident than others. However, some studies also associate higher SCZ risk among highly industrialised countries and first or second-generation migrants. For instance, few studies point out an increased risk of SCZ within ethnic minorities and Afro-Caribbean immigrants in the United Kingdom. Hypotheses that may explain such data include stress during migration, potential maternal malnutrition, and even exposure to diseases. With this example, hopefully, we all may appreciate how the aetiology of SCZ and other complex diseases are confounded by environmental factors. In addition, how such factors may profoundly influence an individual’s genome. SCZ is a clear example of how genetic predisposition, the presence of essential gene variants characteristic of a disease, may act as a blueprint to a terrible disease waiting to be “built” by certain factors as if they promote such development. It is remarkable how genetic elements and their interactions with many other factors may contribute almost collectively to disease pathogenesis. We can reflect this to a famous quote amongst clinical geneticists: “genetics loads the gun, and environment pulls the trigger.” Carrying high-risk genes may increase the susceptibility to a complex disease, and an environment that promotes such disease may tip the balance in favour of the disease. However, finding and understanding the “blueprints” of SCZ, what executes this “blueprint”, and how it works is still an area of ongoing research. Furthermore, how the interplay between genetics and external factors can lead to profound effects like disease outcomes is still a relatively new subject. The Epigenome: the Environment’s Playground To review, it is clear that genes are crucial in complex disease aetiology. In the case of SCZ, high-risk genes and variances are highly attributed to disease onset and pathogenesis. However, we also see with twin studies that genetics alone cannot explain the high degree of differences between twins, particularly when referring to SCZ concordance between identical twins. In other words, external factors are at play, influencing one’s susceptibility and predisposition to SCZ. These differences can be explained by the effects epigenetics have on our genome. Epigenetic mechanisms regulate gene expression by modifying the genome. In short, on top of the DNA double strands, the genome consists of additional proteins, factors, and even chemical compounds that all aid the genetic functions our body heavily relies on. The key to epigenetics lies in these external factors’ ability to regulate gene expression, where some factors may promote gene expression whilst others may prevent it. Epigenetic changes alter gene functions as they can turn gene expression “on” and “off”. Furthermore, many researchers have also shown how epigenetic changes may accumulate and be inherited somatically with cell division and even passed down through generations. Therefore, epigenetic changes may occur without the need to change any of the DNA codes, yet, they may cause a profound effect by controlling gene expression throughout many levels of the living system. These underlying mechanisms are crucial for the environment’s effect on complex diseases. Some external factors may directly cause variances or even damage to the genome (e.g. UV, ionising radiation), and other sources may indirectly change gene expression by manipulating epigenetic changes. The exact molecular genetics behind epigenetic mechanisms are elaborate. However, we can generally find three common epigenetic mechanisms: DNA Methylation, Histone Modification, and Non-coding RNA. Although each method works differently, they achieve a common goal of promoting or silencing gene expression. All of these are done by the many molecular components of epigenetics, altering the genome without editing the gene sequence. We refer to the epigenome, which translates to “above the genome”, the genome itself and all the epigenetic modifiers that regulates gene expression on many levels. Environmental factors and exposure may influence epigenetic mechanisms, affecting gene expression in the cell or throughout the body, sometimes permanently. Therefore, it is clear how the epigenome may change throughout life as different individuals are exposed to numerous environmental factors. Furthermore, each individual may also have a unique epigenome. Depending on which tissues or cells are affected by these mechanisms, tissues or cells may even have a distinct epigenome, unlike the genome, which is theoretically identical in all cells. One example of this is the potential effects of DNA methylation on schizophrenia epidemiology. DNA methylation can silence genes via the enzymes DNA methyltransferases (DNMT), a family of enzymes capable of catalysing the addition of methyl groups directly into the DNA. The DNMT enzymes may methylate specific nucleotides on the gene, which usually would silence said gene. Many researchers have found that the dysregulation of DNA methylation may increase the risk towards the aetiology of numerous early onset neuro-developmental disorders. However, SCZ later-onset development also points towards the influence of environmental risk factors that target DNA methylation mechanisms. Studies show links between famines and SCZ increased prevalence, as the DNMT enzymes heavily rely on nutrients to supply essential amino acids. Malnutrition is thought to play a considerable role in DNA methylation changes and, therefore, the risk of SCZ. Small Piece of a Changing Puzzle Hopefully, we can see a bigger picture of the highly intricate foundation beneath complex diseases. Bear in mind that SCZ is only one of many complex diseases known. SCZ is ultimately not a pristine and impartial model to study complex disorders. For instance, concordance rates of complex diseases change depending on their genetic background. In addition, they may involve different mutations, variance, or dysregulation of differing pathways and epigenetic mechanisms. After all, complex diseases are complex. Finally, this article aimed to give a rundown of the epigenetics behind complex diseases like SCZ. However, it is only a snapshot compared to the larger world of the epigenome. Furthermore, some questions remain unanswered: the genetic background and architecture of complex diseases, and ways to study, diagnose, and treat complex diseases. This Scientia article is one of the articles in Scientia on the theme of complex disease science and genetics. Hopefully, this introductory article is an insight and can be used to reflect upon, especially when tackling more complicated subjects of complex diseases and precision medicine. Written by Stephanus Steven Related articles: Schizophrenia, Inflammation, and Accelerated Ageing / An Introduction to Epigenetics

By no means is this an exhaustive list on all the terminology relating to the COVID-19 pandemic. For more information, please refer to the World Health Organisation (WHO) and the Centers for Disease Control and Prevention (CDC). AAdenovirus- a group of related viruses. They were first removed from human adenoid glands (found at the back of the throat), hence the name. Asymptomatic- where a person is infected by the virus but does not present any symptoms. Go Back Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Glossary for COVID-19 terms Last updated: 23/01/25 Published: 28/12/22 Key terms By no means is this an exhaustive list on all the terminology relating to the COVID-19 pandemic. For more information, please refer to the World Health Organisation (WHO) and the Centers for Disease Control and Prevention (CDC). – A Adenovirus- a group of related viruses. They were first removed from human adenoid glands (found at the back of the throat), hence the name. Asymptomatic- where a person is infected by the virus but does not present any symptoms. Can still pass the virus and infection onto others. C Coronavirus- a group of related viruses that cause diseases in mammals and birds. Named after the crown-like spike protein on the virus’s surface- ‘corona’ in Latin for crown. COVID-19/ COVID – the disease that coronavirus causes D DNA- deoxyribonucleic acid, the cell’s code to life. DNA instructs how to make proteins, which are essential for function in the body. Double helix. E Epicentre- the central point of the virus outbreak. This changed during the COVID-19 pandemic depending on the variant of virus. Epidemic- an outbreak in a localised area at a particular time H Herd immunity- when enough people are protected against the disease, that it lends immunity to those who are not protected. Can achieve protection against the disease through either previous infection, and/ or vaccination. I Immunity- achieving immunity means to be protected from future infections by viruses, and bacteria for example. You can achieve immunity through either previous infection, and/ or vaccination. Immunosuppressed- the immune system is suppressed. In other words, people who are immunosuppressed have a reduced ability to fight diseases. Thus preventing them from being infected in the first place is of great importance. Infection- the unnormal invasion of microorganisms into the body. Some infections present symptoms- at least straight away- while others do not show any symptoms. L Lockdown- preventing people from leaving where they are, to stop the transmission and contain the virus in the COVID-19 pandemic. M Mass vaccination- vaccinating many people in a certain area at a particular time mRNA- messenger RNA (ribonucleic acid). Single helix. Acts as a go-between for DNA and the proteins that are being made. P Pandemic- a global, or national outbreak Protein- an important molecule. Used as a fuel source, a building block, a carrier among other things, in the human body. R Restrictions- impeding or hindering movement and travel during the COVID-19 pandemic, in order to contain the spread of the virus and curb transmission. S Shedding- (in biology) refers to viruses casting off viral particles which can then infect others Side effects- effects that are different and potentially harmful from the main, intended effects of a medication, treatment, or vaccine. Examples of some side effects: headaches, aches, pains, fever. Symptomatic- where a person is infected with the virus and does present symptoms. Can still pass the virus and infection onto others. Symptoms- the signs a person has been infected; this can be physical or mental. With COVID-19, you can show symptoms as symptomatic, or not present symptoms as asymptomatic, if infected. Examples of symptoms for COVID-19 include loss of taste and smell, a persistent cough, fever. T Transmission- how a particular disease, in this case coronavirus, is passed from one person to another. V Vaccination- the administration of vaccine into the body. Vaccine- a form of active immunity, where a weakened, live version of the infection agent is administered into the body. The immune system kicks in and destroys the infection agent, but not before taking note of the genetic material (e.g. mRNA or DNA from the protein) from the agent. The immune system will use this genetic material to ‘remember’ the infection next time it appears, so it can prepare a speedier, more efficient response. Vaccine hesitancy- uncertainty as to whether people should take the vaccine. This could be due to a variety of reasons: being unfamiliar with the vaccine and its contents, and/ or being distrusting of the government and those in the health organisation. Viral load- the amount of virus (or viral genetic material) a person has in their body at a particular time. A person not infected with the virus will have no viral load, whereas a person infected with the virus will have a much higher viral load. Virus- a microorganism. Some spread diseases as vectors, while some are ‘better’. To date, it is being argued whether viruses are alive or not. W Wuhan- Capital of Hubei Province in China. First epicentre of coronavirus. Written by Manisha Halkhoree Related article: The origins of COVID-19

Cortisol is a glucocorticoid steroid hormone produced by the zona fasciculata segment of the adrenal gland, following stimulation by the release of adrenocorticotropic hormones from the pituitary gland. Chronic stress is associated with excessive cortisol production and the development of neurodegenerative diseases.  Go Back Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Stress and neurodegeneration Last updated: 30/01/25 Published: 10/03/23 Cortisol is a glucocorticoid steroid hormone produced by the zona fasciculata segment of the adrenal gland, following stimulation by the release of adrenocorticotropic hormones from the pituitary gland. Chronic stress is associated with excessive cortisol production and the development of neurodegenerative diseases. Once cortisol is produced and released into circulation, it crosses the blood-brain barrier to bind to and activate nuclear glucocorticoid receptors (GR) in the hippocampus. Upon cortisol binding, the GR undergoes conformational changes, causing it to dissociate from its chaperone complex and consequently allowing for the transcription of target genes. One such pathway that is activated as a result of GR binding is the brain-derived neurotrophic factor (BDNF) and the cAMP response element-binding protein (CREB) pathway, which is important for long-term memory formation and consolidation. However, memory formation can be impaired following abnormal BDNF/ CREB pathway activation due to elevated cortisol levels. Moreover, high cortisol levels have been found to cause increased amyloid-beta (AB) deposition, which is evident in Alzheimer's disease patients. Therefore, increased blood cortisol levels result in increased activation of GR, causing impaired gene expression and affecting cellular functions. When GR are exposed to cortisol over a long period of time, such pathways become further impaired, resulting in the characteristic neurodegenerative disease pathology in affected individuals. A study conducted by Kline et. al assessed the relationship between high cortisol levels and neurodegenerative disease pathology in mice. In this study, it was noted that chronic stress reduced the diversity of the gut microbiome in mice, and such alterations resulted in increased gut permeability, promoting the movement of pathogens across the epithelial lining, and increasing AB deposition in affected mice. However, AB deposition can be reduced if cortisol levels are controlled. For example, xanamem, a drug currently in clinical trials, reduces cortisol levels by inhibiting the 11B-hydroxysteroid-1 ezyme, known to play a role in the activation of cortisol via the hypothalamus-pituitary-adrenal axis. Therefore, xanamem or similar compounds, if suitable following clinical testing, could be a means of decreasing AB deposition, thereby targeting one component of neurodegnerative disease pathology. If the putative hypotheses of Alzheimer's disease aetiology are correct, this would potentially ameliorate patient symptoms and offer a degree of improved quality of life for affected individuals. Written by Maria Zareef Kahloon Related articles: Tetris and PTSD / Mental health awareness / Physical and mental health

Manufacturing doubt is another strategy where facts are intentionally changed to promote an agenda. It is used in the tobacco industry and against the climate crisis. Meaning articles can maintain the façade of using scientific methods by referencing sources that are difficult to interpret whilst research supported by sound evidence is labelled and downplayed. Go back Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link How fake science websites hijack our trust in experts to misinform and confuse Last updated: 07/11/24 Published: 29/12/22 In science, all research is peer-reviewed by experts. Now, fake science websites are mimicking these disciplines. These websites capitalise on our trust in experts. In some cases, these websites are paid to publish fake science. This is becoming more common. In a recent global survey, almost 50% of respondents said they see false or misleading information online daily. By understanding the methods these sites use we can prevent their influence. Hyperlinking is a technique used to convince website users. They reassure the user that the content is credible, but most people don’t have experience in analytical techniques and so these links aren’t questioned. Repetition is used to increase the visibility of fake science content but also saturate search engines. This content can be repeated and spread across different sites. Users of “lateral reading” get multiple websites that corroborate the fake science from the initial source. Many of these sites only choose articles that agree with their perspective and depend on the audience not taking time to follow up. Manufacturing doubt is another strategy where facts are intentionally changed to promote an agenda. It is used in the tobacco industry and against the climate crisis. Meaning articles can maintain the façade of using scientific methods by referencing sources that are difficult to interpret whilst research supported by sound evidence is labelled and downplayed. On fake science websites first, check the hyperlinked articles. These websites will use sites with repeated content from disreputable sites. Next, look at the number of reposts a website has. Legitimate science posts are on credible websites. Some websites investigate websites that feature fake science. Ultimately, these websites thrive on users not having the time or skills to look deeper into the evidence, so doing so will help expose the fake websites. Written by Antonio Rodrigues Related articles: Digital disinformation / COVID-19 misconceptions

Lyra is a prominent constellation, largely due to Vega which forms one of its corners, and is one of the brightest stars in the sky. Interestingly, Vega is defined as the zero point of the magnitude scale - a logarithmic system used to measure the brightness of celestial objects. Technically, the brightness of all stars and galaxies are measured relative to Vega! Go back Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link The Lyrids meteor shower Last updated: 14/11/24 Published: 10/06/23 The Lyrids bring an end to the meteor shower drought that exists during the first few months of the year. On April 22nd, the shower is predicted to reach its peak, offering skygazers an opportunity to witness up to 20 bright, fast-moving meteors per hour which leave long, fiery trails across the sky, without any specialist equipment. The name Lyrids comes from the constellation Lyra - the lyre, or harp - which is the radiant point of this shower, i.e. the position on the sky from which the paths of the meteors appear to originate. In the Northern Hemisphere Lyra rises above the horizon in the northeast and reaches the zenith (directly overhead) shortly before dawn, making this the optimal time to observe the shower. Lyra is a prominent constellation, largely due to Vega which forms one of its corners, and is one of the brightest stars in the sky. Interestingly, Vega is defined as the zero point of the magnitude scale - a logarithmic system used to measure the brightness of celestial objects. Technically, the brightness of all stars and galaxies are measured relative to Vega! Have you ever wondered why meteor showers occur exactly one year apart and why they always radiate from the same defined point in the sky? The answer lies in the Earth's orbit around the Sun, which takes 365 days. During this time, Earth may encounter streams of debris left by a comet, composed of gas and dust particles that are released when an icy comet approaches the Sun and vaporizes. As the debris particles enter Earth’s atmosphere, they burn up due to friction, creating a streak of light known as a meteor. Meteorites are fragments that make it through the atmosphere to the ground. The reason that the Lyrids meteor shower peaks in mid-late April each year is that the Earth encounters the same debris stream at the point on its orbit corresponding to mid-late April. Comets and their debris trails have very eccentric, but predictable orbits, and the Earth passes through the trail of Comet Thatcher in mid-late April every year. Additionally, Earth’s orbit intersects the trail at approximately the same angle every year, and from the perspective of an observer on Earth, the constellation Lyra most accurately matches up with the radiant point of the meteors when they are mapped onto the canvas of background stars in the night sky. The Lyrids meteor shower peaks in mid-late April each year. Image/ EarthSky.org This year, there is a fortunate alignment of celestial events. New Moon occurs on April 20th, meaning that by the time the Lyrids reach their maximum intensity, the Moon is only 6% illuminated, resulting in darker skies and an increased chance to see this dazzling display. Written by Joseph Brennan

Your brain is truly an extraordinary structure, and it’s the reason you can do all the amazing things you do. This mass of wrinkly material weighs only about 1.3 kilograms, yet it controls every single thing you will ever do. It’s the engine that drives our behaviour and allows us to interact with the world.  Go Back Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Discovering the Wonders of the Human Brain Last updated: 18/11/24 Published: 13/04/23 Your brain is truly an extraordinary structure, and it’s the reason you can do all the amazing things you do. This mass of wrinkly material weighs only about 1.3 kilograms, yet it controls every single thing you will ever do. It’s the engine that drives our behaviour and allows us to interact with the world. Despite its relatively small size — the brain makes up only 2% of our body mass — it’s an incredibly energy-intensive organ. In fact, it consumes more than 20% of our oxygen supply and blood flow and uses more energy than any other tissue in the body. This is because it has a dense network of neurons, specialized cells that transmit signals throughout the nervous system. There are around 100 billion neurons in the human brain, each connected to thousands of other neurons, passing signals to each other via trillions of synapses. The human brain has more connections than there are stars in the Milky Way galaxy and it can process information at a speed of up to 120 meters per second! Even when you are asleep your brain never really “shuts off”! While you’re snoozing away, your brain is busy consolidating memories, processing emotions, flushing out harmful toxins and keeping your mind sharp and healthy. One more key feature that sets our brain apart is the cortex, the outer layer of the brain responsible for many of the higher cognitive functions that are unique to humans, such as abstract reasoning and language. While all mammals have a cerebral cortex, the human cortex is disproportionately large, accounting for 80% of our total brain mass, and it’s much more complex than any other animal. Now, have you ever wondered how the human brain compares to the brains of other animals? Some animals have much larger brains than we do. For instance, the brain of a sperm whale weighs around 8 kilograms, making it the largest brain of any animal on Earth. To put it into perspective, that’s about five times the size of a human brain! Similarly, the brains of elephants are also much larger than ours, weighing in at around 5 kilograms. Comparative neuronal morphology of the cerebellar cortex in afrotherians, carnivores, cetartiodactyls, and primates. We might not have the largest brain compared to other species however, the human brain is larger than most animal brains relative to body size. Why did humans evolve such large brains in the first place? The question has puzzled scientists for years, but there are a few theories that have gained traction. The “social brain” hypothesis suggests that our large brains evolved as a result of our ancestors’ increasingly complex social structures. As early humans began to live in larger groups, they needed to be able to navigate the complex social dynamics of their communities, for example cooperating for resources and maintaining social relationships. Another theory known as “ecological intelligence”, suggests that the pressure for larger brains was driven by environmental conditions. Our ancestors had to adapt to the challenges posed by the environment, such as finding food and shelter. Finally, the “cultural intelligence” hypothesis emphasizes the challenge of learning from different cultures and teaching their own. While each of these theories has some evidence to support it, there is still much debate among scientists about which theory (if any) is the most accurate. It is likely that all three theories played a role in the evolution of the human brain, to varying degrees. The human brain is a fascinating organ that has captivated scientists are researchers for centuries. Despite all our advances in neuroscience, however, there is still so much that we don’t know about how the brain works and what it is truly capable of. Written by Viviana Greco Related article: The brain-climate connection REFERENCES González-Forero, M., & Gardner, A., 2018. Inference of ecological and social drivers of human brain-size evolution. Nature, 557(7706), Article 7706. https://doi.org/10.1038/s41586-018-0127-x Jacobs, B., Johnson, N. L., Wahl, D., et. al, 2014. Comparative neuronal morphology of the cerebellar cortex in afrotherians, carnivores, cetartiodactyls, and primates. Frontiers in Neuroanatomy, 8. https://doi.org/10.3389/fnana.2014.00024

Obesity is one of the most common problems among many in all age groups. As per world health organisation obesity or overweight defined as abnormal or excessive fat accumulation that may cause impair health. Obesity measured by BMI (Body mass index), normal BMI for children is  range Go back Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link Childhood obesity Last updated: 18/11/24 Published: 25/03/23 Obesity is one of the most common problems among many in all age groups. As per the World Health Organisation, obesity or overweight is defined as abnormal or excessive fat accumulation that may cause impaired health. Obesity is measured by Body Mass Index (BMI). The normal BMI for children ranges from 13.53 to 20.08. Children are the most vulnerable age group for becoming overweight. Early prevention reduces the overall burden of health care system globally. Obesity causes: Obesity mainly results from imbalance between energy intake and utilisation of calorie intake. There are several reasons for becoming overweight. Five main causes for overweight are- Genetic factors Food quality and quantity Parental belief Sedentary lifestyle Environmental resource Symptoms of childhood obesity: Shortness of breath while physical activity Difficulty in breathing while sleeping. Easily fatigue. Gastric problems such as gastroesophageal reflux disease Fat deposits in various body parts such as breast, abdomen and thigh area Prevalence The prevalence of overweight children is increasing every year. In England, in the year 2019/2020, the prevalence of overweight increased rapidly. The National Child Measurement Program measure shows that in Reception (4-5 years old), the obesity rate was 9.9% and continued to increase to 21% in year 6. Childhood obesity is tackled early so complications can be managed before it worsens. There are many ways to prevent childhood obesity. Prevention The National Institute for Health and Care Excellence guidance currently recommends lifestyle intervention as the main treatment for prevention of childhood obesity. Diet management and physical activity are the main areas to focus on for obesity prevention. Dietary modification includes limited use of refined grains and sweets, potatoes, red meat, processed meat, sugary drinks, and alternatively increase intake of fresh fruits and vegetables, whole grain and adopt more healthier food options, instead of fatty and junk food. On top of that, add physical activity in daily routine. It is one of the key factors for reduction of obesity. Another way for communities to tackle obesity is to take part in government programmes such as Healthier You and NHS Digital weight management programme, which are helpful for handling obesity. Written by Chhaya Dhedhi Related articles: Depression in children / Childhood stunting in developing nations / Nature vs nurture in childhood intelligence

Chemistry is such a diverse science branching into many industries and its understanding is fundamental in unlocking solutions to overcome diseases, viruses and infections. The science has a central application in the pharmaceutical drug manufacturing process. In medicine, Chemistry helps understand diseases and medical samples through the various analytical and instrumental methods – which in turn aids medical research and the development and discovery of drugs. Go back Facebook X (Twitter) WhatsApp LinkedIn Pinterest Copy link The role of chemistry in medicine Last updated: 17/11/24 Published: 13/04/23 Chemistry is such a diverse science branching into many industries and its understanding is fundamental in unlocking solutions to overcome diseases, viruses and infections. The science has a central application in the pharmaceutical drug manufacturing process. In medicine, chemistry helps understand diseases and medical samples through the various analytical and instrumental methods – which in turn aids medical research and the development and discovery of drugs. Chemical synthesis has allowed scientists to synthesise new compounds which can be used to treat a range of diseases and medical conditions. The study and knowledge of chemistry is very essential for professionals involved in the healthcare sector including doctors and nurses. The fact is that it cannot be denied that chemistry plays a dominant role in the day-to-day life of a healthcare professional. With the help of chemistry alongside biochemistry and biology, diseases and disorders can be easily diagnosed. The knowledge of chemistry has allowed for the understanding of the science behind pregnancy tests and COVID-19 PCR tests using UV-VIS Spectroscopy. Chemistry also plays a key role in the development of new medical technologies, such as diagnostic tools and imaging equipment. Magnetic resonance imaging (MRI) relies on principles of chemistry and is an application of nuclear magnetic resonance (NMR), an analytical tool for chemists found in laboratories. The technique uses strong magnetic fields and radio waves to produce detailed images of organs and body tissues. The scan uses contrast agents using elements iron and gadolinium to enhance the clarity of images. Overall, chemistry is an essential discipline for advancing our understanding of health and disease, and for developing new treatments and technologies to improve human health. Interesting fact: vaccines for rabies and anthrax were discovered by Louis Pasteur – a famous chemist. Written by Khushleen Kaur Related articles: AI in medicinal chemistry / The role of chemistry in space