Generation Bridge Project

Today, I attended an event conducted at a nursing home as a part of The Generation Bridge Project. The project was introduced to us at school as a former student had founded it – throughout the year, I, along with my group did fundraising activities such as tombolas to raise money to fund the project.

The ultimate aim of the project is to reduce the isolation felt by the elderly population in society by engaging them in activities such as music, dance, board games etc. Although some outdoor activities had been planned, the rain didn’t allow for that, but we managed to have a good time indoors – we were even able to get some of the residents to do the macarena! 

I took part in the talent show part of the event by singing – the people present were extremely supportive and created a welcoming atmosphere for us to partake in. There were many entrancing performances that not only provided entertainment of the residents but also allowed us to grow in confidence. After this we were treated to food – pizza and a wide variety of desserts certainly made the day more enjoyable!

It was an incredibly rewarding experience as we had the opportunity to talk to some of the elderly and how much they valued our company was apparent. Some of the residents were challenging to approach as they had anger issues or could not understand us well enough to hold a proper conversation – however, finding ways to work around these problems added to the experience!

It was particularly inspiring to see members of the project who support the cause every year regardless of how busy their lives must be. The founder of the project at the end of the event made a speech that emphasised the importance of care workers in our country who dedicate their lives to improving those of people who are vulnerable, and highlighted the importance of appreciating the elderly – Britain is an ageing population and we will all, some day, grow old and it is vital that we treat the elderly population in our community with the same respect that we would want to be treated with. 

 

Lab Work Experience – University of Leicester

Hi everyone ! I’m sorry about not posting sooner, I’ve been quite busy with exams and things.

This week, I had the opportunity to shadow a research associate at the University of Leicester who was working to determine the role of dopamine in the motor control of vertebrates. Zebrafish were used to conduct experiments to investigate this. I will briefly summarise my four days there:

On my first day, I was given the opportunity to become more familiar with the microscopes used in a lab as being able to use them correctly played an essential role in almost all the experimental procedures carried out. After being shown a patch-clamping procedure, I was able to try it once myself – although it was very frustrating at times, I found it an enjoyable experience

On the second day, an experiment was carried out to observe startle and freeze responses in the fish. A looming stimulus was provided using a virtual reality setup and the behaviour of the fish was observed and recorded using a camera. We encountered some difficulties in this as the temperature of the room was difficult to maintain and as the fish prefer higher temperatures, they did not swim much. A control group of fish were compared to a group of fish that had their dopamine receptor cells removed. However, due to the described problem, it was difficult to obtain enough responses to reach a conclusion – further repeats would be needed to determine a relationship

On the third day, I had the opportunity to practice pinning the fish to the agar plate, which was an incredibly difficult task due to how delicate the fish were. It was particularly difficult in five-day old fish than in the younger ones as the older fish develop a gas bladder which allows it to float – this makes it difficult to hold the fish in place. Patching was done again, however a patch of cells in the brain were observed rather than single neurones as on the first day. I was also able to remove the brain from a fish that had been fixed overnight to determine whether the dopamine receptor cells were present, This took patience but I was able to obtain an intact brain in the end! It was an extremely rewarding task!

On the fourth day, as the research associate I was initially shadowing was on leave, I observed a different research associate in the same lab who was helping a student at the university with her behaviour experiments (which I had carried out on day 2). This allowed me to gain a new perspective on the experiment as this associate was particularly experienced in behavioural assays. After lunch, I switched over to a research associate who was working on locusts – I had the opportunity to place electrodes in the muscles of a locust leg to monitor the electrical signals delivered when the locust kicked. I was then able to dissect the thorax of the locust which revealed its relatively simple nervous system compared to that of humans. The nerve responsible for the fast extension of the locust leg was identified and cut to show its function – however I accidentally cut another nerve with it as it was difficult to distinguish between the different nerves when they were in a bundle-like arrangement.

Overall, I found this a very useful experience and I am sure the work will help me in the neuroscience aspect of Year 13 biology as well as my general understanding of the applications of science in a practical setting to investigate problems.

How do we benefit from the microorganisms that live within us?

Hi everyone! A short while ago, I submitted an entry for a Cambridge Essay Competition titled, “How do we benefit from the microorganisms that live within us?” and I would like to share it with you:

Introduction:

Not all microorganisms are pathogens, yet the terms are often used synonymously. It is important to distinguish between the microbes that are beneficial, the pathogens that cause illness, and the commensal microorganisms that neither help nor harm. Being unaware of these categories and how to preserve the useful microbes can lead to choices that may have adverse effects on our health.

The human microbiota:

There are microorganisms found in most parts of the body. One of the most highly diverse communities of microbes are found on the skin. These make up the normal skin microflora. Many of the microorganisms living here are beneficial to the host as they are involved in protecting the skin against invasion. For example, Bacillus subtilis is a bacterium dwelling on the skin that produces a toxin known as bacitracin which acts as an antibacterial agent against other microbes. It has also been suggested that the skin microflora may be involved in enhancing the ability of T-cells to respond appropriately to pathogens[1].

A healthy microbial population in the reproductive tract is important to reproduce successfully as they have roles in gamete production, pregnancy and delivery of babies. Lactobacillus sp. is a bacterium found in the vagina that produces lactic acid – this is thought to be significant in lowering the pH of the environment which is a protective measure that prevents many infections and diseases including sexually transmitted diseases and urinary tract infections. In men, microbes have been discovered in lower parts of the genital tract which have a mixture of effects. For example, some unknown strains of Corynebacterium have been linked to prostatitis as they are abundant when an individual experiences the condition but decrease in concentration during treatment[2]. However, different species of coryneform bacteria form a large part of the normal microbiota which implies that most of these are either commensal or play a role in protecting against invading pathogens. It has also been suggested that interactions may occur between the microbiomes of the male and female genital tracts but there is not enough evidence to indicate this.

Most of the microorganisms found in the human body are in the gastrointestinal tract. There are thousands of different species of microbes in the human gut microflora alone.

Bacteroidetes and Firmicutes are the most abundant phyla in the gut, followed by Actinobacteria[3]. Bacteroides species, though have been described in the past to have a commensal relationship, where they do not have any effect, with the host, it has been suggested that it may be more accurate to describe it as a symbiotic relationship where both the bacteria and the human host experience benefits. An example of the advantages of Bacteroides is that they, along with other bacteria residing in the intestines, ferment carbohydrates forming fatty acids that can be used as a source of energy by the host. The energy gained from this contributes significantly to meeting part of the host organism’s energy demand. This has been demonstrated by experiments where the calories required to maintain body mass in germfree rats compared to normal rates was observed. The results show that the rats lacking a microbial population needed 30% more calories[5].

The abundance profile of microbes in the digestive tract have been shown to be affected by diseases such as obesity and inflammatory bowel disease. Though different studies contradict each other, a link has been suggested between the Firmicutes-Bacteroidetes ratio and obesity and some evidence shows that measuring this ratio in children can reveal predispositions to conditions like obesity later in life. Conducting further research to understand the mechanisms involved in this may allow the non-invasive manipulation of the microbiota of our gut to be used as a preventative measure or as part of treatment for weight-related health conditions[6].

Inflammatory bowel disease is a term used to describe a range of conditions where inflammation of the intestines occurs. While it is often categorised as an autoimmune disease, studies have suggested that it may be due to the immune system attacking the non-pathogenic microbes in the gut. This leads to inflammation which then causes injury of the bowel[7]. In patients with inflammatory bowel disease, the proportion of Bacteroidetes were shown to be significantly lower than the Actinobacteria and Proteobacteria concentrations[8]. The correlations between the abundance of microbes and the phenotypes of disease can allow us to hypothesise more accurately about the causes of the disease. However, it is currently unknown how inflammation and the microbiome influence each other. Nonetheless it is clear that trying to gain an insight into the mechanisms that connect the microbiota and inflammatory bowel disease could transform methods of diagnosis or even treatment of the disease. 

The microorganisms in the gut have a key role in the prevention of infections due to pathogens. For example, Clostridium Difficile is a pathogen and exists in small numbers in the bowel but does not cause harm as the other bacteria present there create a balance. Taking antibiotics when they are not necessary or using broad-spectrum antibiotics can disrupt this balance as many species of microbes may be wiped out by antimicrobials. The consequent decrease in the diversity and abundance of the gut microbiota means that pathogenic microbes are more able to flourish as the harmless microbes that use up the resources found in the intestines are less prevalent, so there is not as much competition[9]. In the 1900s, when it was observed that mice treated with the antibiotic streptomycin were more susceptible to infection due to Salmonella, the idea that intestinal microorganisms may have the potential to prevent invading bacteria to grow successfully, by a mechanism known as colonisation resistance, was recognised. Colonisation resistance can be divided into two categories: direct and indirect; direct colonisation resistance is where the microorganisms in the gut directly compete with exogenous pathogens for a resource, such as carbohydrates, or produce inhibitors that restrict the growth of particular pathogens. In indirect colonisation resistance, the intestinal microbes induce a specific immune response to target groups of invading microorganisms. For example, B. thetaiotaomicron can stimulate the host to produce certain types of antimicrobial substances[10]

The gut microbiota, aside from preventing pathogenic proliferation, helps in the development of the mucosal immune system. The presence of commensal microorganisms allows the immune system to become familiar with the antigens of many harmless microbes so that it can distinguish them from pathogens. The toll-like receptors in the membranes of lymphoid and epithelial cells in the small intestine are central to this process of recognition. The molecular patterns associated with harmless microorganisms such as the components of some bacterial antigens are recognised by these receptors and they promote tolerance to the constituents of a normal healthy microbiota.

In the womb, a foetus is thought to be germ-free – the baby’s first exposure to microbes is when it passes through the vaginal canal during birth. In order to prevent an acute inflammatory response which could harm the baby when it first encounters microbes, the receptors decrease their activity for a short period of time after birth to allow a microbial community to establish itself [11]. This may indicate that the body acknowledges the microbiota as necessary for the maturation of the immune system. The microbes in the nasal cavity, though little is known about them, may also have a role in determining immune response. 

Conclusion

There are a myriad of ways in which we benefit from the microorganisms that live within us. Due to its wide range of beneficial roles that are vital in maintaining our health, the microbiota of our body is sometimes referred to as an organ[12] and should therefore be treated with care. 

Bibliography

[1] Anil Kumar, Nikita Chordia (2017) Role of Microbes in Human Health [online]

Available at: https://www.omicsonline.org/open-access/role-of-microbes-in-human-health-2471-9315-1000131.php?aid=88460 

[Accessed on: 06/03/2019]

[2] Silver Türk, Sandra Mazzoli, Jelena Štšepetova, Julia Kuznetsova, Reet Mändar (2014) Coryneform bacteria in human semen: inter-assay variability in species composition detection and biofilm production ability [online]

Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3927743/ 

[Accessed on: 07/03/2019]

[3] Sai Manasa Jandhyala, Rupjyoti Talukdar, Chivkula Subramanyam, Harish Vuyyuru, Mitnala Sasikala, D Nageshwar Reddy (2015) Role of the normal gut microbiota [online]

Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4528021/ 

[Accessed on: 04/03/2019]

[4] Thryve editors (2018) The Layout of the Human Microbiota [online]

Available at:  https://blog.thryveinside.com/the-layout-of-the-human-microbiota/

[Accessed on: 04/03/2019]

[5] Hannah M. Wexler (2007) Bacteroides: the Good, the Bad, and the Nitty-Gritty [online]

Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2176045/#r208 

[Accessed on: 05/03/2019]

[6] Liene Bervoets, Kim Van Hoorenbeeck, Ineke Kortleven, Caroline Van Noten, Niel Hens, Carl Vael, Herman Goossens, Kristine N Desager,and Vanessa Vankerckhoven (2013) Difference in gut microbiota composition between obese and lean children: a cross-sectional study [online]

Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3658928/#__sec13title 

[Accessed on: 05/03/2019]

[7] Minesh Khatri, MD (2017) Inflammatory Bowel Disease [online]

Available at: https://www.webmd.com/ibd-crohns-disease/inflammatory-bowel-syndrome#1

[Accessed on: 06/03/2019]

[8] Jun Kim Ph.D. (2018) Inflammatory Bowel Disease And Microbiome [online]

Available at: https://blog.thryveinside.com/inflammatory-bowel-disease-and-microbiome/

[Accessed on: 06/03/2019]

[9] Elana Pearl Ben-Joseph, MD (2015) The Danger of Antibiotic Overuse [online]

Available at: https://kidshealth.org/en/parents/antibiotic-overuse.html

[Accessed on: 05/03/2019]

[10] Wikipedia contributors (2019) Colonisation Resistance [online]

Available at: https://en.wikipedia.org/w/index.php?title=Colonization_resistance&oldid=882815428

[Accessed on: 06/03/2019]

[11] Veronica Lazar, Lia-Mara Ditu, Gratiela Gradisteanu Pircalabioru, Irina Gheorghe, Carmen Curutiu, Alina Maria Holban, Ariana Picu, Laura Petcu, Mariana Carmen Chifiriuc (2018) Aspects of Gut Microbiota and Immune System Interactions in Infectious Diseases, Immunopathology, and Cancer [online]

Available at: https://www.frontiersin.org/articles/10.3389/fimmu.2018.01830/full

[Accessed on: 06/03/2019]

[12] Eisen J. (2012) Meet your microbes

Retrieved from: https://www.ted.com/talks/jonathan_eisen_meet_your_microbes/up-next

[Accessed on: 04/03/2019]

Cambridge Subject Masterclass: Medicine

A few weeks ago, I attended a Medicine Masterclass held at the University of Cambridge and found it massively beneficial, so I thought I’d share it here.

It was a long drive to Cambridge and waking up at 5:30 to get there in time was a challenge, to say the least. Nonetheless the experience was worth it. As soon as we arrived, we ventured out of the safety of the parking lot to try and find some packed lunch. Thankfully, it wasn’t long before we located a café in the law faculty.

With a sausage roll and a packet of crisps in hand, I made my way to the lecture theatre. I was momentarily concerned by the idea of spending a whole day in a room full of strangers, but this worry soon faded away when I met someone who, like me, had travelled to get there and didn’t know anyone. The first thing I noticed about the hall was its size – it was huge! Luckily, my newly formed acquaintance and I had arrived relatively early and were able to choose our seats. I do not know if I was more stunned by the sheer size of the room or the fact that there were enough people attending to completely fill the space! 

The room that was buzzing with chatter quietened down as the stage lights came on and it was time to begin. The first talk was on pathology, done by one of the lecturers at the university. She briefly talked us through her academic and professional journey that led to her current position as an honorary consultant in pathology before tackling misconceptions about pathology and the role of pathologists. I was surprised that autopsies were the smallest part of being a pathologist! Regardless of this, she detailed how an autopsy would be carried out and a hypothetical case study was given where an elderly woman living alone had been found dead by a neighbour. The examination of the organs using photos allowed us to identify a perforated stomach. This led to discussions about peritonitis, how it can lead to death, and how it may be caused by a lymphoma. Tests that would be carried out to determine whether the woman suffered from lymphoma were also described. There was an interactive element to the session which I found particularly engaging as we had an opportunity to see how different people attending interpreted the information provided in a different way and how this may lead to misconceptions in our general understanding of several issues.

There was soon a short break where we were able to feast on our lunch as well as digest the information of the previous session. We made our way to the toilets, which thankfully did not have a mile-long queue, before reclaiming our seats in the lecture hall.

The next talk was on how blood moves around the body. I had initially been puzzled as to what could be explained about this topic beyond the circulatory system which we had been learning about for years in school. It turned out that the circulation of blood is far more complex than I ever could have imagined; I feel that I would need to do further research to extend my understanding on the subject. One of the most fascinating things about the talk was the idea that sometimes our body’s physiological mechanisms can worsen a problem in the body which means that medicine given to treat some conditions may be to first counter the physiological mechanisms to prevent further damage. However, these mechanisms are crucial in surviving periods of environmental stress such as starvation, for example. I hope to learn more in the future about the positive and negative effects of our physiological responses.  

When Breath Becomes Air

A short while ago, I read this amazing book, “When Breath Becomes Air” by Paul Kalanithi, and I wanted to share my thoughts about it here. So, this is the blurb:

What do you do when life is catastrophically interrupted?

What does it mean to have a child as your own life fades away?

What makes life worth living in the face of death?

At the age of thirty-six, on the verge of completing a decade’s training as a neurosurgeon, Paul Kalanithi was diagnosed with inoperable lung cancer. One day he was a doctor treating the dying, the next he was a patient struggling to live.

When Breath Becomes Air chronicles Kalanithi’s transformation from a medical student in search of what makes a virtuous and meaningful life into a neurosurgeon working in the core of human identity – the brain – and finally into a patient and a new father.

 

Being a fiction enthusiast, I would be lying if I said I wasn’t a little hesitant of trying an autobiography. I was expecting a dull narrative: a documentary on paper, almost. I could not have been more wrong.

When I saw the name of the author, I suspected that he might be South Indian as Kalanithi is a Tamil name, which piqued my interest. By the end of the book, my suspicions had been confirmed as his wife Lucy referred to eating dosa with the Kalanithi family which is a traditional Tamil dish. Being a Tamilian myself, knowing this made the book even more relatable; for example, when Paul describes his mother’s fears of a poor education for her children when they move to Arizona and her efforts in finding him books to prepare him for college, I felt that I could understand this since my family holds similar views on the importance of education. However, there are bounds to relatability; Afterall, there is only so much a person can find relatable in a Stanford, Cambridge and Yale graduate!

A quality that I grew to admire in Paul is the way he contemplated the world he lived in – he could have so easily been a philosopher instead of a neurosurgeon. Though some might say he was indeed a philosopher. Paul was a fully rounded person. He could not be seen just as a neurologist or a philosopher or a book-lover, because he was all those things and those different aspects to him somehow interact with each other as he seeks to find the connection between morality, literature, philosophy and science.

Kalanithi’s way of thinking and seeing the world certainly changed my own perspective. So, I suppose this book, if nothing else, taught me that autobiographies are not boring! I was quite astonished at how much I felt like I knew the person who had written this masterpiece. The idea of learning about the likes, dislikes, interests and insecurities, the little quirks of not a character in a fantasy world but a real person is quite mind-boggling (in a good way)

I hope to read more great books in the future that offer a new perspective on medicine as powerful and inspiring as this one.

Operating Theatre Live Experience

Recently, I attended an event called Operating Theatre Live and this consisted of a day full of talks on different aspects of the human anatomy and opportunities to dissect organs of a pig.

When I arrived at the venue after a long drive, everyone was given a stethoscope, scrubs and a face mask to prevent contamination and the spread of disease. We were also given a booklet with questions to fill in throughout the day (a tactic to ensure everyone was paying attention!).

We started the day by looking at the cranial cavity. I found the layers between the brain and the cranium bone known as the meninges particularly interesting because they were so varied in their functions. The outermost layer is the dura mater and as we were able to see during dissection, it is very tough and provides structural support for the brain. The next layer is the arachnoid mater which is sub arachnoid space filled with cerebral spinal fluids. This gives the brain its shock absorbance and distributes nutrients as it is rich in glucose. The layer closest to the brain is the pia mater which consists of thin vasculature. The dissection part, though it upset my nose, allowed the different meninges layers to be separated from each other and observed individually. I was particularly surprised by how small the brain was! The brain that my group were dissecting had lost some structural integrity and I learnt that this may be due to the brain beginning to break down after death.

After completing the brain dissection, I was grateful to have a breath of fresh air before my lunch of a sandwich and prawn and cocktail crisps (the best!). The next talk was going to be on the thoracic cavity.

Not knowing whether I should expect a bell to mark the end of lunch, I decided to not risk anything and rushed back to the hall as soon as I finished eating and arrived just in time. We started by learning about the ribs and how the last three ribs share a costal cartilage and then moved on to the heart and the lungs. When dissecting, we were able to feel how tough the trachea was and attempted to follow its path into the lungs to the very end (though this proved to be very difficult!). I was stunned by the sheer number of bronchioles that were present – there were probably hundreds, or even thousands!

Next, it was time to explore the heart. After learning the names of the various parts of the heart, we moved on to dissection. We cut the heart into horizontal sections from the bottom upwards and had to be careful to not change the orientation of any of the sections when arranging them in order. This method of dissection allowed us to see how much thicker the left wall of the heart is in comparison to the right and we could see whether the difference in thickness between the sides changes.

It was then time for dinner, after which the final session of the day on bones would be held. This session was optional, so the group sizes decreased dramatically. During this, I learnt about the structure of bones and the processes by which bones are built and broken down. However, the focus of the session was fractures and we learnt about different types of fractures such as spiral which is where twisting has occurred and compound – this is where the bone is no longer encompassed by soft tissue but is torn through it. For the dissection element, we carried out an amputation. This experience gave me insight into how strong bones are and how tendons and soft tissue play a significant role in protecting the bone from external damage.

This experience helped me understand the human body a bit more and I’m sure it will prove useful in my Biology A level as well as my medical career.

Hello!

Hi! I’m Keerthi, I’m doing Biology, Physics, Chemistry and Maths at A level and I would like to pursue a career in Medicine so here, I’ll post about any work experience or voluntary work or literally anything I think is relevant to that. In my free time, I play the keyboard, sing and dance.