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BIO-CHEM
ENGINEERING
MATHS
PHYSICS
1
Introduction
With a new editorial team taking over, we have brought some fresh
ideas with us. We really hope you enjoy the new font, the new
Maths section, the book reviews and the “Intrigued?” page in
addition to the articles, which span from superhero science to
quantum tunnelling.
The team of writers and editors is very proud to welcome you to
the fifth issue of the Wilson’s Intrigue STEM, written for students
by students.
Our Mission
• Expand your knowledge
• Contribute to the Wilson’s community
• Make complicated parts of science more accessible
• Popularise science and make it more interesting
• Inspire creativity through wider research
Acknowledgements
The magazine simply could not be produced with such finesse
without the inquiring journalism of the writers and the multiple
zoom calls the new editors have attended to learn and master
formatting in Publisher. A massive thank you to all students
involved for their contributions!
A special thanks must go to Mr Benn, Mr Carew-Robinson, Dr
Cooper, Mr Jackson, Mr Lissimore, Miss Roberts and Dr Whiting for
proofreading and verifying the accuracy of our articles and the
magazine as a whole.
If you would like to write in the sixth issue of the STEM magazine to
research and discover a new aspect to the subjects, please email
me (Divy) at DAYALD@wilsonsschool.sutton.sch.uk for more
information.
Founded by Devanandh Murugesan and his team of
editors in September 2019
Front Cover: This majestic deep sea creature is known as a siphonophore. It is
estimated that there are 175 different species of this class, and although it appears
to be one large organism, it is in fact a colonial organism composed of two
specialised zooids.
2
The Wilson’s Intrigue Team
Editors
Divy Dayal (Chief Editor) Y12
Nabeel Abdul Rasheed Y12
Aditya Chougule Y12
Aditya Jain Y12
Atharva Narkhede Y12
Mann Patira Y12
Writers
Adam Ali Y12 Kinshuk Jain Y12 Sanuka
Arya Narang Y11 Karun Kirubananthan Gunawardena Y12
Dulain Gamage Y12 Y12 Shinujan
Folaju George Y11 Matteo Cascini Y11 Saravanamuthu Y12
Syed Shah Y12
Jonathan Peter-Rajan Mohamed Ahmed
Y11 Y12 Tathushan
Moksh Sachdeva Y12 Subenthiran Y12
Junaid Ali Y12
Junayd Soobratty Y12 Prabhas Vedagiri Y12
3
Contents
If you are viewing this digitally, you can click on the titles of the articles or sections.
BIO-CHEMISTRY MATHS
RNA Vaccines: The Copycats 6 Accuracy of Modelling 39
Inside the Cytokine Storm 8 Wonders of Euler’s Number 41
Curing Acute Lymphoblastic Leukaemia 10 Doomsday Argument 43
A Vaccine and a Virus 12 Prime Tuples 45
The Heart that Never Beats 14 Infinite Series and the Real World 47
Growing New Teeth 16
New: Intrigued? - Organ Donation 17
Can Chloroquine Treat Malaria? 19
How to Use Antibodies to Treat Asthma 21
COMPUTING PHYSICS
Neuromorphic Computing 25 Quantum Tunnelling 50
Quantum Computing: The Future? 27 Startling Subatomic Particles 52
Volumetric Displays 54
ENGINEERING
The Flying V 30
It’s Nanotech, You Like It? 32
Autonomous Vehicles 34
Hydrogen or Electric Cars? 35
How Accurate is the Flash? 36 REFERENCES 56
4
DID YOU KNOW?
Dragonflies were one of the first flying
winged insects (almost 320 million years
ago). Today the biggest dragonflies have a
wingspan of 14 cm, however, fossil records
suggest ancient dragonflies had wingspans
of up to two feet!
5
Bio-Chemistry Section
Inside the Cytokine Lymphoblastic Heart that Never Growing New Teeth
Storm Leukaemia Beats
What has
The immune system Cancer in the blood Artificial Hearts in translational dentistry
in action p8 p10 action p14 discovered? p16
One vial (0.45ml) contains 5 doses
of 30 micrograms of BNT162b2 RNA
entire complex in place while a peptide
bond forms between the two amino
acids through a condensation reaction.
The ribosome then moves along the
mRNA molecule, repeating this
process until a stop codon (UAA, UAG
or UGA) is reached. At this point, the
polypeptide chain stops growing and
detaches from the ribosome [5].
The polypeptide later folds into its
precise three-dimensional shape,
specifically an antigen of the infectious
agent that the vaccine is tailored
towards. In the case of Covid-19, this
antigen comes in the form of the
crown-like spike protein which gives
the coronavirus its name. As is typical
RNA Vaccines: The Copycats
during a primary immune response,
the antigen is displayed on the
surfaces of specific cells known as
antigen-presenting cells or APCs
How RNA vaccines are the key to future pandemics
(which include macrophages, dendritic
By Nabeel Abdul Rasheed (Y12) cells and B cells). Here, it acts as a
M
signal to trigger an immune response
any a GCSE biologist is well- enclosed within a special coating to which eventually leads to
acquainted with the protect the mRNA from extracellular immunological memory (through the
traditional vaccine – RNA-degrading enzymes in the body production of B memory cells and T
memorised religiously and (which detect and eliminate aberrant – memory cells). In effect, the immune
reproduced on exam paper as ‘a dead meaning atypical or deviant – mRNAs system can now respond much more
or weakened form of a disease- as part of cellular homeostasis) [2,3]. quickly and on a larger scale if the
causing pathogen’. But more recently, Once the mRNA reaches the target actual pathogen were to enter the
indeed in the last few weeks, scientific cells, it is thought to settle into small body [1,6].
discussion has shifted away from cup-like depressions in the plasma
Benefits and Drawbacks
these classical live-attenuated or membrane known as caveolae (Latin
inactivated versions and instead for ‘little caves’), before entering the As you might imagine, a novel
towards a newer, altogether more cell through caveolar endocytosis in technology like the RNA vaccine comes
exciting prospect: the RNA vaccine. membrane-bound sacs called vesicles with more than its fair share of risks
[4]
. and rewards. Chief among the
Details & Mechanism
advantages are:
Having entered the cell, the mRNA can
As is the case in all other types, the
then bind to a ribosome floating in the Safety: Despite the government’s best
purpose of the RNA vaccine is to train
cytoplasm or one attached to the efforts, the issue of vaccine safety is
your immune system to respond
rough endoplasmic reticulum, ready one of continued public concern, as
rapidly to a specific infection by
for the familiar process of protein illustrated by the ever-growing anti-
mimicking the infectious agent. What
translation. Two transfer RNA (tRNA) vaccine campaign. In the case of the
distinguishes it from more established
molecules, each carrying a specific RNA vaccine, there is no chance of
counterparts is the mechanism by
amino acid, align themselves next to infection because it is entirely free of
which this agent is introduced into the
mRNA codons which are pathogen particles. Once the antigen is
body: rather than injecting the
complementary to their own ‘memorised’ by B and T memory cells,
pathogen itself, the RNA vaccine
anticodons – the start codon being the mRNA is degraded by intracellular
comprises a messenger RNA (mRNA)
AUG, which codes for the amino acid ribosome-degrading enzymes – a
strand that codes for a disease-
methionine. The ribosome holds the process likened quite aptly by
specific antigen [1]. This sequence is
6
THE WILSON’S INTRIGUE | BIO-CHEMISTRY Issue 5 | April 2021
ScienceNews to “a Mission Impossible message that self- Delivery: As mentioned previously, the RNA-degrading
destructs once it has been played” [2,7]. enzymes in the body make delivery of the vaccine to body
cells quite challenging. The most common drug delivery
Efficacy: The most striking example of an effective RNA
system used to combat this are lipid nanoparticles, tiny
vaccine is undoubtedly the most recent one of them all.
spherical molecules which can carry lipid-soluble drugs in
BNT162b2, as it is fondly named, was developed by
their cell membrane bilayer. They contain protruding
biotechnology giants Pfizer and BioNTech and consists of
surface proteins known as homing peptides which allow
a modified mRNA encoding a mutated form of the SARS-
for specific, targeted drug delivery. What’s more, lipid
CoV-2 spike protein. Large-scale clinical trials involving
nanoparticles ensure high encapsulation efficiency of
more than 43,000 participants demonstrated a vaccine
mRNA, ease of transport and reduced risk to body cells
efficacy rate of 95%, measured from seven days after the
and immune system compared to alternative methods
second of two doses [8]. This was consistent across most [12]
.
demographics, so much so that in early December 2020,
the UK became the first country in the world to approve Storage: Many RNA vaccines need to be frozen or
the coronavirus vaccine – ordering over 800,000 within refrigerated, owing to the instability of the RNA molecule
the first few days [9]. Up to now, the largely successful itself and the temperature-sensitive nature of the lipid
results of this project serves as testament to the nanoparticles. The Pfizer-BioNTech vaccine must be
potential of the RNA vaccine. Even so, in the context of stored at -70°C, almost four times colder than the
vaccine trials, a sample size of 43,000 may not represent average household freezer [7]! Such demanding
all demographics to the degree of validity associated with requirements may be difficult to reach for countries with
other, non-emergency use vaccines – thus paving the way limited or no refrigeration facilities; even for those
for more extensive research in the near future. privileged with this infrastructure, the cost of
procurement and transportation acts as yet another
Production: RNA vaccines have the added advantage of
barrier to large-scale vaccine distribution [2].
being produced much more rapidly and easily in
standardised laboratory procedures than traditional The Future
vaccines. In fact, the German biopharmaceutical company
Unsurprisingly, a strong focus of current RNA vaccine
CureVac (which specialises in mRNA technology) believes
research is aimed at developing and improving the
that it would only take two months to produce an RNA
current mRNA sequences used in the COVID-19 vaccines –
vaccine for influenza. Perhaps more importantly, the
particularly minimising side-effects and making the
drastically lowered production period would enable swift
molecule more suitable to everyday conditions. However,
rollout of vaccines during pandemics, once again
this looks likely to be overshadowed by the even more
illustrated by the invaluable efforts of Pfizer and
daunting prospect of new, emerging variants of the virus
BioNTech [1,2].
– growing areas of concern for governments and
Equally, however, the problems associated with any biotechnological companies alike.
medical treatment cannot simply be ignored. Just as
Looking further ahead, RNA vaccines may well hold the
there have been major reasons to celebrate, we are also
key to further advances in multi-purpose treatment,
faced with numerous challenges when it comes to RNA
providing protection for more than one disease at a time
vaccines:
(as has already been achieved in conventional vaccines
Side-effects: While the RNA vaccine may be free of for a select few diseases – most notably the MMR vaccine
pathogenic material, it can on rare occasion induce which protects against measles, mumps and rubella) [3].
adverse effects on users, the most recent of which Research and clinical trials are also being carried out on
involved two NHS workers suffering allergic reactions to RNA vaccines that could be used to encode cancer
the Pfizer-BioNTech vaccine just one week after it was antigens and stimulate immune responses against
approved for use in the UK. Both suffered an malignant tumours [3]. This may even become a form of
anaphylactoid reaction (not to be confused with immune- personalised treatment by tailoring the mRNA to the
mediated and life-threatening anaphylaxis), but were unique properties of the tumour cells of that particular
later treated and soon restored to full health. Some individual [1].
allergists and immunologists believe this type of reaction
Whatever the future holds, it seems increasingly likely
to BNT162b2 could be linked to the compound
that RNA technology will play a major part in it, making it
polyethylene glycol (PEG) contained in lipid nanoparticles
of greater interest to us than ever before. Our role both
used to package the mRNA [10]. They believe that a small
as students and members of the public is to continue
number of people previously exposed to PEG may have
educating ourselves of the advances and the shortfalls
high levels of antibodies against it, putting them at risk –
encountered along the meanders of its development.
however small – of an anaphylactic reaction to the
Only then can we hope to leave behind a society rife with
vaccine [11]. Nevertheless, this theory is supported by
uncertainty and scepticism into one which offers hope
limited evidence as of yet, and the general consensus is
and remedy for all.
that initial side-effects are “common with new
vaccines” (the words of Professor Stephen Powis, medical Edited by Aditya Chougule
director for the NHS in England) [10].
7
THE WILSON’S INTRIGUE | BIO-CHEMISTRY Issue 5 | April 2021
Inside the Cytokine Storm
By Aditya Chougule (Y12)
O
ur immune system is both a blessing and a curse. Its intricacies allow for a phenomenal structured
defence against invaders but these intricacies also mean a great deal more places for mistakes to be
made. As such many diseases arise from malfunctioning of the immune system, the very organ that
swore to protect us. One poignant example of this is the cytokine storm. Particularly relevant at the
moment, the cytokine storm is a terrifying condition whereby an overabundance of cytokines can cause
hyperinflammation and can lead to multi-system organ failure and eventually death.
cellular apoptosis- programmed cell death- and
inhibit carcinogenesis and viral replication [3].
Essentially, all these cytokines play a wide variety of
roles and communicate with a multitude of organ
systems, making their betrayal even more
frightening.
Those reading this will likely have heard of cytokine
storm from the news in relation to COVID-19 but in
fact there are quite a few triggers for cytokine storm
besides a viral pathogen. Indeed, there are three
Cytokine distribution [1] types of cytokine storm: iatrogenic, pathogen-
induced and monogenic. Pathogen-induced cytokine
Key to the disease process of cytokine storms is (you
storm probably sounds more familiar than the other
guessed it) the role of cytokines; these tiny proteins
two since it is the most common cause for the
are tremendously important in coordinating the
condition; it results from naturally occurring
immune response since they act as regulatory
microbial infections and viral invaders. In sepsis-
signals that activate effector cells and also help to
associated cytokine storm (sepsis being a life-
resolve the immune response. There are a few
threatening reaction to an infection), very often the
cytokines that have a higher significance over others
collateral damage caused by the immune response
in the context of a cytokine storm- specifically
interferon-γ, interleukin-1, interleukin-6, and TNF-
and as such they are usually found in elevated
levels in the midst of a cytokine storm. Interferon-γ
is primarily secreted by activated T cells (Th1 and
cytotoxic T lymphocytes) and natural killer cells
and is a potent activator of macrophages, which
engulf pathogens and cells by phagocytosis [1]. The
interleukin-1 cytokines are a family of 11 cytokines
that have a wide range of biological functions,
including acting as a leukocytic pyrogen (mediator
of fever) and activating macrophages and Th17
cells, the latter acting as helper cells that
coordinate the immune response [2]. Interleukin-6 Cytokine storm pathway [1]
is one of the more complex cytokines since it is
produced by and acts on immune and nonimmune
cells across multiple organ systems- it is an
important mediator of the acute inflammatory
response and in increasing antibody production.
And last but not least, TNF (tumour necrosis factor)
is a proinflammatory cytokine with a vast array of
functions; although its primary role is to induce
fever, augment inflammation, and activate
antimicrobial responses through interleukin-1 and
interleukin-6 producing cells, TNF can also induce
8
THE WILSON’S INTRIGUE | BIO-CHEMISTRY Issue 5 | April 2021
as it attempts to clear the pathogen can be more (sensitivity measuring the proportion of positives
deadly than the pathogen itself, which is why that are correctly identified) and specificity of 0.73
sepsis has such a high mortality rate [4]. Iatrogenic (specificity measuring the proportion of negatives
and monogenic cytokine storms are quite different that are correctly identified) in patient trials- very
but equally as terrible. An iatrogenic trigger is that encouraging figures [6].
caused by medical treatment, for example,
As for treatment, very often it simply involves
infusion of CAR T cells (T cells which have been
supportive care to maintain critical organ function
genetically engineered to target cancer cells) has
as well as control of the underlying disease- in the
been shown to induce cytokine storm with excess
case of a bacterial trigger this would include
levels of interferon-γ and interleukin-6 [1]. antibiotics, for example- and immunosuppression,
Additional iatrogenic causes of cytokine storm such as with the use of corticosteroids like
include gene therapies, immune checkpoint dexamethasone, to limit collateral damage
inhibitors, cardiac-bypass surgery and allogeneic induced alongside the cytokine storm. Eliminating
stem-cell transplantation. Furthermore, a particular cytokine that is elevated in the blood
monogenic disorders- genetic disorders caused by using treatments such as anti-interleukin-6, anti-
a single gene mutation- can also trigger cytokine TNF, anti-interferon-γ, or anti-interleukin-1β
storm, although this is rare, along with
antibody therapies may be effective in some
autoimmune and neoplastic diseases. For
instances. However, it may also propagate the
example, in patients with primary HLH autosomal
underlying disease if given too soon, especially if
recessive monogenic abnormalities this leads to
the cytokine storm has been caused by a
defects in effector and regulatory mechanisms in
pathogenic invader. Hundreds of
the immune system, which results in overactive
immunomodulatory drugs are currently under
histiocytes and lymphocytes without a pathogenic
investigation for treatment of COVID-related
trigger [5]. In patients with secondary HLH, viral,
cytokine storm; successful examples include the
autoimmune or neoplastic disorders lead to a
interleukin-6 receptor antagonists tocilizumab and
cytokine storm. For example, patients lacking
sarilumab- drugs used to treat rheumatoid
functional perforin, which is critical for resolving
arthritis which have showed to reduce mortality
infections and inflammation, have prolonged T-cell
from 35.8% to 27.3% when compared with
production of interferon-γ and TNF, so when they standard care and found to significantly improve
are infected with a viral pathogen, secondary HLH- survival as well as cutting time spent in hospital by
associated cytokine storm develops and it a week to ten days in patients with severe COVID-
becomes very difficult to shut off the immune 19 (REMAP-CAP trial) [7].
response; a self-reinforcing inflammatory spiral
ensues, leading to multi-organ failure and likely I’d like to finish by lauding the work of healthcare
death [1]. professionals and scientists in helping the world
get a grip on this pandemic. While there are many
In the COVID-19 sphere, a distinct positive lessons to be learned from the past year, we must
correlation between the nasopharyngeal viral load stop to appreciate the selfless work that these
and cytokine levels in ICU patients suggests that people carry out and what they are willing to risk
those with high viral loads are more susceptible to to help others. So, THANK YOU!
cytokine storm [1]. Also, comorbidities such as
hypertension, diabetes and obesity are associated Edited by Mann Patira
with more severe cases of COVID-19, possibly
because of the pre-existing chronic inflammatory
state or a lower threshold for the development of
organ dysfunction, thereby increasing
susceptibility to cytokine storm in these patients.
Surprisingly, it has been found that classic
cytokine storm identification methods, such as the
2004 HLH criteria and the 2016 macrophage
activation syndrome criteria, each missed at least
75% of COVID-associated cytokine storm patients,
while classifying many others as false positives.
Lacking an acceptable scale, scientists at Temple
University in Philadelphia created their own
Temple Criteria using patient data to determine
whether a patient had cytokine storm from COVID-
19; the method had a sensitivity of 0.84
9
THE WILSON’S INTRIGUE | BIO-CHEMISTRY Issue 5 | April 2021
Can Stem Cells Help Cure Acute Lymphoblastic Leukaemia?
By Aditya Jain (Y12)
What is leukaemia? into a different type of cell, for example, a skin
L
cell cannot create a neuron. Our body does,
eukaemia is a cancer caused by the
however, have some multipotent stem cells left.
uncontrolled division of white blood
They are stored in the bone marrow, brain and
cells. There are two categories of
some other organs. There are three types of
leukaemia: fast spreading acute
stem cells: totipotent stem cells – the best
leukaemia and slow spreading chronic
example of which is the zygote and can
leukaemia [1]. Acute leukaemia further splits into
differentiate into any cell and create a whole
two categories: acute myeloid leukaemia and
organism; pluripotent stem cells – the ones in
acute lymphoblastic leukaemia. In this article I
the embryo four days after fertilisation which
will focus on acute lymphoblastic leukaemia
can also differentiate into any cell in the body
which, unfortunately, is one of the most
but not a whole organism; multipotent stem
common cancers in children.
cells – found in the foetus and in specific tissues
How does acute lymphoblastic leukaemia in the body and can only differentiate into those
occur? tissues [4].
Acute lymphoblastic leukaemia is a condition
that affects the bone marrow. The cells of the
bone marrow have a mutation in which portions
of two non-homologous chromosomes are
switched. As a result, the cells are stuck in the
early stages of development and are immature.
This means that they do not function effectively,
so lose their ability to properly produce mature
blood cells and uncontrollably divide,
overcrowding the bone marrow and causing
cytopenia. These faulty chromosomes also
cause the intracellular proteins of the cell to fold
incorrectly and so the cells cannot function and
divide as they normally would be able to. Acute
lymphoblastic leukaemia leads to the release of
large volumes of premature white blood cells. Stem cell potency hierarchy
As a result, this means that the number of red
blood cells and platelets are reduced (cytopenia) Why are stem cells vital?
which can cause tiredness and breathlessness.
Being premature, the white blood cells are The stem cells in our body help promote normal
ineffective in fighting off viruses and other function and allow the body to produce new
infections, allowing the viruses to proliferate to cells to repair minor damage, for example. The
other places like the brain and liver [2]. adult blood stem cell in our bone marrow can
differentiate into different types of cells that are
What are stem cells? vital to normal body function as displayed in the
Stem cells are undifferentiated human cells that diagram. Without the adult bone marrow stem
are able to develop into many different cell cell, we would not have any white blood cells
types. This can range from muscle cells to brain that protect us from pathogens or the red blood
cells. In some cases, they can also fix damaged cells that are essential to allow aerobic
tissues [3]. Most of the cells in our body are not respiration and not even the platelets that help
stem cells, they can only replicate through stop bleeding. Therefore, stem cells are
mitosis, creating copies of themselves. These extremely necessary & vital to the body. When
therefore are very specialised and adapted to stem cells stop functioning properly, the
their function; they cannot just suddenly turn patient’s immune system is likely to be
10THE WILSON’S INTRIGUE | BIO-CHEMISTRY Issue 5 | April 2021
compromised; the likelihood of catching with either healthy stem cells from a donor
infections, therefore, increases. (allogenic) or the patient’s own stem cells
(autologous), which are purged and frozen for
Blood stem cell differentiation preservation, removing any leukaemia cells from
the sample, and then infused back into the
blood, after chemotherapy [6].
This treatment can significantly improve the
survival chances of cancer patients. In a study of
508 patients the eight-year survival average was
65% in patients less than 30 and 38% in patients
less than 60 [7]. This treatment provides many
How does stem cell therapy help cure acute benefits and forms of the treatment are already
lymphoblastic leukaemia? in use. For example, in Europe, more than
26,000 patients are treated with blood stem
Stem cells are extraordinary in our body
cells and this is only going to grow with time [8].
considering their ability to develop into different
cell types. They can, therefore, help to prevent Drawbacks of therapy
or cure diseases such as heart disease, spinal There are many potential concerns with stem
cord injuries and diabetes, as well as cancer. As cell therapy:
part of multipotent stem cell therapy, the cells
used here form a specific germ layer after the • Risk of cancer: the stem cells could divide
differentiation of pluripotent stem cells, and can uncontrollably and cause cancer once
give rise to one or two specialised cells. This again; this means that it could actually
type of therapy is proven to be effective and has harm the person even further, affecting
been used for decades in haematopoietic stem their normal function and not actually
cell transplantation. Haematopoietic stem cell helping them.
transplantation uses either allogeneic stem cells • Rejection: the immune system attacks and
(stem cells from another individual) to replace destroys these stem cells since they are
the defective ones found in the bone marrow or foreign; to reduce risk of this the patient
autologous cells from the patient’s own body could take immunosuppressants and also
that have the leukaemia cells removed. These take cells from a blood relative to help
cells will now produce the correct lymphocytes reduce the chance of rejection.
that function properly and do not uncontrollably
divide. • Graft vs Host disease: transplanted stem
cells or bone marrow contains cells from
This type of stem cell therapy involves the use of the donor’s immune system; these cells
bone marrow as a treatment to haematologic can sometimes recognise your own tissues
and lymphoid cancers – mainly acute as being foreign and attack them.
lymphoblastic leukaemia. The underlying cause
of the cancer may be that the patient has faulty Although stem cell therapy is still in its infancy,
genes producing defective cells which can cause its benefits and widespread uses mean that it is
problems like the uncontrollable division of T- likely going to flourish in the future. With further
cells. The way this treatment works is that bone research and development, I believe stem cell
marrow from a healthy individual with matching therapy will be at the forefront of our fight
antigens (to help avoid rejection) is transplanted against cancer, and will be the next major
into the bone marrow of the patient. Replacing revolution in patient healthcare, just like
the bone marrow means that healthy antibiotics and vaccines were before it.
intracellular proteins are produced which yield Edited by Aditya Chougule and Atharva
healthy precursors, thereby, reducing the Narkhede
production of unhealthy and defective
lymphocytes [5]. The old cancerous cells are
either already killed due to previous
chemotherapy or surgery. These are replaced
11THE WILSON’S INTRIGUE | BIO-CHEMISTRY Issue 5 | April 2021
A Vaccine and a
Virus
By Moksh Sachdeva (Y12)
W
hat is a virus?
A virus is an
obligate
parasite made
of proteins and
sometimes a membrane
made of lipids containing
single stranded or
double stranded DNA or
RNA. Viruses cannot
replicate on their own
however they can
replicate in living cells. A spherical with themselves into a
virus can also affect the icosahedral symmetry. modified form of a cell
behaviour of the host Prolate – this is a membrane where either
cell. It is estimated that common arrangement an internal membrane
over one million different for bacteriophage (a (such as the nuclear
viruses infect virus that infects membrane) or the outer
invertebrates on earth. bacteria) heads and membrane (that
Viruses can be argued to consists of an surrounds the infected
be alive since they can icosahedron elongated host cell) allows them to
persist independently, along one axis. gain a viral envelope.
however some may Helical – this shape may Complex – this shape
argue viruses are not consist of a central cavity possesses a capsid that
alive since they are or hollow tube and tend is unlike the other
unable to replicate to form a helical shapes and may also
independently [1]. structure since they tend possess other structures
to be stacked a central such as a complex outer
What is the structure of axis. wall or a tail of protein.
a virus? Envelope – these types
Viruses don’t have a of viruses envelop
specific shape since they
display a variety of sizes
and shapes otherwise
known as morphologies.
In general, they can be
summarised into five
main morphological
virus types [1]:
Icosahedral - these are
most animal viruses
however some animal
viruses may be near
12THE WILSON’S INTRIGUE | BIO-CHEMISTRY Issue 5 | April 2021
A virion, which is more the surface antigens due weakened or inactive
commonly known as a to point mutations. A pathogen into the body
complete virus particle, point mutation is a where white blood cells
has a protective coat of genetic mutation where a then produce antibodies
protein called a capsid single nucleotide base is that would be able to
which surrounds the changed, inserted or combat the virus if it were
nucleic acid. The virus deleted from the DNA or encountered by
may also have gained a RNA sequence of an traditional infection.
lipid envelope from the organism. This results in Vaccines harness the
membrane of the host the wrong amino acid natural activity of the
cell. Proteins encoded being produced, thus immune system to better
from the viral genome altering the shape of the prepare it for the
make up the capsid and protein. Often, when a exposure of a particular
the shape of the capsid virus drifts a vaccine may virus [3].
allows for morphological still be effective. This is
distinction. due to the change in the The different types of
protein structure being vaccines [4]
How does a virus work? minimal and so the virus The Oxford vaccine is
Viruses work by attaching is still recognised by the composed of a weakened
onto specific molecules antibodies. However, version of the common
on the cell surface. A when a virus shifts the cold virus which has
penetration virus will be vaccine is no longer indeed been genetically
endocytosed into the cell. effective. When a virus engineered to produce
The capsid will remove shifts, a major change in proteins from the
the exposing nucleic acid the antigens surface coronavirus.
and then the replication occurs accompanied by Nuclei acid (mRNA) host
of nucleic acid and virus fusion. Virus fusion makes spike protein.
synthesis of protein coats can be described as the These are safe and quick
will occur allowing the process by which to develop but difficult to
virus to replicate. enveloped viruses enter store and this is similar to
the host cells. The shift the vaccine developed by
Why is it so hard to leads to a major change in Pfizer for Covid.
control viruses? the antigens and so they
Whilst a vaccine may help are much less likely to be Edited by Aditya
the body to produce recognised by the Chougule
antibodies to combat the antibodies which were
virus, the vaccine cannot produced in response to
eradicate the virus from the vaccine. Thus, the
the general population vaccination is not very
since it is not feasible to effective [2].
have everyone
vaccinated. Furthermore, What is a vaccine?
over time a vaccine may A vaccine is a device that
no longer be effective for helps prepare the body to
preparing the body to produce antibodies for a
produce the required virus so that it can fight
antibodies since the virus the virus when it
would have mutated. A encounters it. Vaccines
virus mutates through are designed to prevent
either drifting or shifting. the replication of a virus
When a virus drifts, a in a cell rather than treat
minor change occurs in them. A vaccine injects a
13THE WILSON’S INTRIGUE | BIO-CHEMISTRY Issue 5 | April 2021
The Hearts that Never Beat
By Shinujan Saravanamuthu (Y12)
T
he heart is the blood? Not quite. Jarvik began his work on
driver of the body, However, mechanical artificial organs in 1971
with a simple hearts may be humanity’s and the Jarvik-7 was
function yet with next evolution in our conceived around 1982 [3].
such complex intricacies, quest to become cyborgs;
giving it the strength to a hunk of titanium The Jarvik-7 was designed
channel up to 9000 litres strapped to the chest with to completely replace the
of blood a day. When the a motor spinning at heart so the diseased
heart fails many face the 10,000 RPM seems to be heart had to be removed
only option of a heart the vital next step- for its installation. It is
transplant- receiving a impractical maybe- but composed of two bell-
donor heart is life lifesaving indeed, and in shaped plastic, shown to
changing, a second chance the medical world that will the right and titanium
at life but granted at the do. pumps that take the place
expense of another. of the two ventricles (the
Unfortunately, however, main chambers that
this is not accessible to deliver the final flow of
everyone; as of July 2020 blood to the lungs and
there are 343 patients in body). It works by sewing
the UK who have been on the cuff end of the
placed onto a waiting list pump to portions of the
for a donor heart [1]. Even atria that remained when
though donor numbers the heart was originally
are increasing, with removed. After attaching
people now having to opt the pump the chest is
out of being a donor, it is closed, leaving two
still not meeting demand flexible plastic tubes
with patients having to Robert Koffler Jarvik extruding from the torso,
wait on average 1085 which are attached to an
days for a transplant- one external air compressor
in six patients do not With all great inventions, which draws and pumps
receive the heart they there is a mastermind, blood to the heart.
require in time [2]. Instead pioneer and successor; for
of a donor heart what else artificial organs it was
can be done… Robert Koffler Jarvik, with
permanently have the Jarvik-7. Born in
someone strapped to a Michigan, in 1946, he was
cardiopulmonary bypass a curious man: always
machine? As well as being either elbow deep into his
impractical, this machine research or a patient
does not maintain blood (quite literally) and
flow, can only sustain the inventing the surgical
body for 45 minutes and is stapler just as a teenager.
only used as a stopgap Working under the wing of
measure during surgery. Williem Johan Kloff- the Jarvik-7
Maybe implant vibranium inventor of the dialysis
to magnetically control machine during WW2-
14THE WILSON’S INTRIGUE | BIO-CHEMISTRY Issue 5 | April 2021
The first patient to receive 2000, and the birth of the implantations [6]. Finally,
the Jarvik-7 was retired Jarvik 2000: a motor the ‘bridges to transplant’
dentist Barney Clark on designed to fit onto the could evolve to become
December 2nd 1982. After heart with a maximum the ‘bridges to
the operation Clark awoke output of up to seven destination’, where the
and was able to live litres per minute [5]. It was pumps could take over
another 112 days; the first implanted into a 61- the heart either giving
Jarvik-7 had extended year old man with enough time for a donor
Clark’s life, but it could be cardiomyopathy- an to be found or for the
argued that he was not inspiring procedure… heart to recover again.
truly living as he was With the leading causes of
mostly bed bound during A skull pedestal, is death in the UK since 2001
this period, trapped within attached to the head as being ischaemic heart
the confines of the the connecting point disease and
hospital. The media between the motor on the cerebrovascular disease,
documented Clark’s heart and the external complete artificial hearts
condition on the road to battery. This is done demonstrate increasing
recovery, however, it was because the scalp tissue is potential in treating
soon clear that Clark was fixed closely to the skull today’s biggest diseases,
not to get any better with so can reduces risk of and with upcoming
the major problem being trauma and damage to inventions such as Total
that the site where the soft tissue- maceration. Artificial there is much
tubes were attached to more to look forward to
[7]
the chest were prone to Then a posterolateral .
infection; this resulted in thoracotomy incision- just
the lungs being below the shoulder blade- Edited by Aditya
compromised and is made and a cruciate Chougule
significantly weaker so (cross-shaped) incision is
unable to support the made at the apex of the
artificial heart. This was in heart, which is then cored,
addition to the high removing a section of
velocity blood that, due to myocardium. When this
constant compression occurs, the pump is then
from the pump, was being inserted to minimise
damaged resulting in the bleeding. The right motor
blood clotting and leading is connected at the now
to a stroke which left open ventricular apex and
Clark paralysed [3]. the blood is then run
through a Gore-Tex sleeve
This sequence of events which is connected to the
led to the fall of the Jarvik descending aorta. During
-7 with the media seeing implantation, the power
it as doctors playing God cable is carried from the
and extending life in apex up to the scapula
return for one at a lower where it is then connected
quality; which was also to the pedestal described
presented in the second above.
patient, William
Schroeder. Ultimately, the This miracle procedure
FDA discontinued the was performed by Dr
Jarvik pumps due to Stephen Westaby as well
quality control resulting in as Bud Fraizer, who
the end for the ‘bridges to impressively improvised
transplant’ [4]. much of the operation,
Fast forward 18 years, to paving the way for future
15THE WILSON’S INTRIGUE | BIO-CHEMISTRY Issue 5 | April 2021
Can We Grow New
Teeth?
By Mohamed Ahmed (Y12)
T
ranslational dentistry (a
collective term for
regenerative dental
medicine and dental
tissue engineering) has been an
active frontier of research over
the past 100 years and it seems
that it may soon be fit for use
today [1].
To understand why dentists
have been looking for ways to
effectively digest or obtain their the adult gum can respond to
grow new teeth back, we have to
food, which demonstrates that ‘tooth-inducing’ signals from
ask why we cannot replace our
evolution has favoured well embryonic tooth mesenchyme in
teeth- like many reptiles and
aligned teeth that are produced a way that is appropriate for in
fish who regrow a new set of
once. vitro (in a living organism)
teeth every few months [2]! In
growth, which would contribute
fact, leopard geckos have been While the process of tooth
to tooth formation.
the ideal model organisms to creation is complicated, it is
use when researching luckily well understood: The issue we face today is in the
mechanisms of teeth growth. essentially, soft and connective ethics of obtaining embryonic
tissue, nerves and blood vessels cells for tooth replacements,
(all found in the pulp at the which may be considered a
centre of the tooth) are bonded frivolous use of the resource
to 3 types of hard tissue: when extractions and other
dentine, enamel and cementum. treatments are available and
Using RNA sequencing, these cells could be used for
researches have deduced more critical procedures (or
differentiation pathways of certainly those who are ethically
stem cells to odontoblasts and opposed to the use of the
ameloblasts which are cell embryo in its entirety), and a
populations that give rise to lack of understanding in the cell
dentine (the softer- but still dynamics- how the cell interacts
In humans and other mammals, harder than bone- tissue closest with its environment- involved
the relevant stem cells needed to the pulp) and enamel (a over the differentiation process.
to build up the adult teeth when harder protective coating of the Research is currently being
we were children die later on in tooth) [4]. conducted to induce the same
our lives whereas these geckos differentiation pathways
The fruits of this research have
form new generations of teeth possible in embryonic stem cells
expedited efforts to replace
(from retained stem cells) which from adult stem cells and to
missing teeth in places such as
grow in size under the tissue, understand how these cell
King’s College London who have
until they surface and displace populations respond to a variety
published their research in the
the more mature tooth above of environmental factors.
Journal of Dental research
the tissue [3]. This is much rarer
where they are able to produce Edited by Aditya Chougule
in mammals due to the
dentine, enamel and roots by
specialization of our teeth in
cultivating adult human gingival
response to more specific and
tissue (from the gums)
evolved dietary needs. For
combined with embryonic tooth
example, carnivores and
mesenchyme (loose multipotent
omnivores have developed
cells in a protein and fluid
canine teeth and molar teeth
mesh). The epithelial cells from
respectively to allow them to
16Intrigued? Organ Donation
Here at the Wilson’s STEM Intrigue, we are very curious and this often leads to big discussions and
debates of scientific news within the magazine writers.
Our new “Intrigued?” section hopes to shed some light on one of our most heated debates, while
hoping to inform and update news you may have missed, and tackle the big questions with STEM.
We surveyed our editors and writers and below are some of the responses.
Poll One :
The New Law:
20th May 2020 marked a defining moment in the
history of organ donation as the new opt-out
system first came into effect in England. Also
known as Max and Keira’s law, this system means
that all adults in England will be “considered
potential donors unless they choose to opt out or
are excluded” (gov.uk). Those excluded from the
plans include: children under 18; people who lack
the mental capacity to understand the changes for
a significant period before their death; people who
have not lived in England for at least 12 months
before their death.
Great! From what I had heard, hospitals were
always short on organ donors, despite the
fact that so many people would happily Slightly queasy but it would help lots of
donate their organs to save other people's people
lives. Having sensible defaults is important William Y12
for anything, but especially where people's @Wilson’sIntrigueOrganDonation
lives are involved.
Michael Y13
@Wilson’sIntrigueOrganDonation The idea is there and it is a good one,
however, I feel that there has been a lack of
effort by the NHS that the law has changed;
I believe that it was a valid decision to make, yes I have seen and heard adverts to opt out
seeing as the majority will be willing to donate but I still don't believe that it it sufficient. Thus
their organs. This would ultimately make life it can lead to controversies and future
easier for many, whilst preserving the freedom problems for organ donation, however , it may
to choose. have seen daunting for people to think about
organ donation especially during the current
Ishan Y11 climate.
@Wilson’sIntrigueOrganDonation
Shinujan Y12
@Wilson’sIntrigueOrganDonation
Poll Two:
As a devout Muslim, my stance on most issues
of morality is motivated by my faith. In the
case of organ donation, many modern Islamic
scholars differ in opinion. Although the most
recent fatwā (Islamic scholarly opinion) is that
organ donation is permissible in Islam
following circulatory arrest, I would rather in
this case err on the side of caution.
Nabeel Y12
@Wilson’sIntrigueOrganDonation
17THE WILSON’S INTRIGUE | BIO-CHEMISTRY Issue 5 | April 2021
Arguments supporting this system include: 80% of people in England support organ donation but only
38% have opted in. This means that families are often left with a difficult decision when a loved one dies.
Moreover, in 2019, 408 patients died in the UK on the transplant waiting list and as part of the law, the
prospective donor’s family will continue to be involved prior to organ donation.
Nevertheless, there are concerns that inaction in an opt-out system may lead to false positives, where
individuals who do not wish to donate eventually become a donor. An opt-out system may also increase
proportions of deceased donations, which are less likely to be suitable on account of possible brain inju-
ry, trauma, hypoxia or cancer prior to death. In the UK, it is estimated that only around 1% of patients
who die do so in circumstances that allow organ donation to proceed. On top of this, some religious be-
lief systems discourage or prohibit organ donation, attaching greater ethical implications to any poten-
tial false positives.
More information can be found at:
https://www.organdonation.nhs.uk/helping-you-to-decide/about-organ-donation/faq/what-is-the-opt
-out-system/
https://www.gov.uk/government/news/opt-out-organ-donation-max-and-keira-s-bill-passed-into-law
Although I am in favour of the opt-out scheme
law, I believe that an opt-in donation scheme
would be better, because it ensures that everyone
who actually wishes to donate their organs are
doing so. It eliminates the cases of uncertainty
where it is unclear whether the donor actually
We need more organs. Opt-in may wishes to donate their organ(s).
prevent those pesky false positives,
Shanjeev
but there is always discussion with the
donor’s family beforehand whether or
not to proceed with the donation. In
most cases, the family should be It saves essential time, and
OPT-IN
aware of the donor’s decision. therefore lives, for those who
Koushikk are in need of organs, which
require extensive waiting lists Control over our own bodies, dead or
which can go on for years. alive, should not be superseded by a
OPT-OUT Opting out increases the need for organs in a hospital.
availability for organs in the Haris
future. However, in the
coming years use of stem cells
It is not worth giving people an opt in and dying hearts are becoming
system when thousands of people are increasingly promising and
dying - action needs to be taken to maybe the need for organs
help these people. Also, when people will decrease.
die, they wouldn’t care whether they
have their organs in their body or not Shinujan
so it shouldn’t be a problem for them
either. It’s a win-win situation.
Arya
What do you think: OPT-IN or
OPT-OUT?
18THE WILSON’S INTRIGUE | BIO-CHEMISTRY Issue 5 | April 2021
Is Chloroquine an
Effective Medication
for the Prevention
and Treatment of
Malaria?
Where Malaria Occurs Across the World
By Junaid Ali (Y12)
M
alaria is a parasitic causes the most deaths parasite must reproduce. To
disease spread by worldwide [5]. do this, it requires energy for
female Anopheles It is also capable of avoiding metabolic processes and
mosquitoes. It is detection from the immune amino acids to create new
widely spread in many tropical system. proteins. The parasite
regions, mainly areas in Africa, achieves this by breaking
Central/South America, Asia Whenever a red blood cell is down haemoglobin. As well as
and parts of the Middle East, infected by P. falciparum, it proteins, haemoglobin is also
because mosquitoes are able expresses a molecule on its made of a heme unit. The
reproduce and complete their surface: P. falciparum heme molecule is toxic to the
growth cycle in areas with Erythrocyte Membrane Protein parasite and soluble. To
high humidity and high -1 (PfEMP1). PfEMP1 is coded protect itself, the malarial
temperatures [1]. Symptoms by var genes in P.falciparum parasite crystallises heme into
may begin any time from 7 to and it is this protein that acts hemozoin – a non-toxic
18 days after being bitten by a as the antigen which should be molecule that forms insoluble
mosquito that carries the detected in an immune crystals.
pathogen. Symptoms can vary response. However, in a P.
and include a high falciparum genome, there are When chloroquine is taken
temperature (>38°c), 50-60 var genes and only one into the body, it enters red
headaches, vomiting, muscle gene is expressed at a time [6]. blood cells by diffusion and it
pains and diarrhoea [2]. This means that the surface occupies the parasite’s
antigen is able to repeatedly vacuole where the
Malaria is caused by single- change so that it is not haemoglobin is digested. The
celled eukaryotes known as detected by the host’s vacuole is acidic, so the
Plasmodium parasites [3]. immune system. In 2018, P. chloroquine gains H+ ions
Plasmodium species develop falciparum made up 99.7% of (protons) and it can no longer
in blood-feeding insect hosts. estimated malaria cases in the leave the vacuole by diffusion.
When the mosquito bites the World Health Organisation Chloroquine is able to limit the
host’s skin, the parasite enters (WHO) African Region, 71% of amount of hemozoin
their bloodstream through the cases in the Eastern molecules that the malarial
mosquito’s saliva. The Mediterranean and 65% in the parasite can crystallise.
parasite can then reproduce in Western Pacific [7]. Therefore, after a certain
the liver asexually. The new point, the parasite can no
parasites then infect red blood Chloroquine is a medicine that longer continue to crystallise
cells and begin to multiply is commonly used in the heme into hemozoin, so heme
asexually. This causes the cell treatment and prevention of begins to build up. Heme binds
to burst, allowing the malaria. It is composed of a to chloroquine to create an FP
parasites to infect more cells combination of various -chloroquine complex. FP-
and the cycle repeats. antimalarials and is typically chloroquine is very toxic to the
taken with another medication parasite and disturbs its usual
There are 5 different species called proguanil [8]. It is able to membrane function. In the
of Plasmodium: P. falciparum, prevent the spread of the end, the parasitic cells break
P. malariae, P. vivax, P. ovale malarial parasite by down and undergo lysis.
and P. knowlesi [4]. P. interfering with the processes
falciparum is the most carried out while it is in the Chloroquine was first
dangerous as it is the most host’s red blood cells. During discovered in 1934 by Hans
common malarial parasite and this phase of the lifecycle, the Andersag. Only in 1947 was
19THE WILSON’S INTRIGUE | BIO-CHEMISTRY Issue 5 | April 2021
enough learnt about its concern. For example, the malaria may arise if
properties for it to be interaction between chloroquine-resistant P.
incorporated into clinical chloroquine and another drug falciparum develop in a certain
practice [8]. Chloroquine is now named cimetidine may lead to area, which could lead to a
a part of the WHO’s Model List increased levels of chloroquine wider spread if it is not
of Essential Medicines and it is in the body due to the controlled. Chloroquine should
available as a general inhibition of chloroquine still be used, but I believe only
medication [9]. The first metabolism [8]. Additionally, under controlled
recorded resistance of the chloroquine in overdose has a circumstances for cases where
parasite towards chloroquine 20% chance of death and can there is shown to be no
was in the 1950s and ever cause problems with vision, resistance to it.
since, chloroquine has breathing, the heart or
gradually become less and less sleeping. Build-up of Edited by Aditya Jain
effective against P. falciparum chloroquine deposits in the
[10]
. This is because the body can result in blurred
parasites have evolved due to vision and blindness.
natural selection and are able
to channel chloroquine away Overall, it is clear that
from its vacuole. This means chloroquine is an invaluable
the drug is incapable of medicine as it is extremely
interfering with the parasitic useful in the prevention and
cell’s processes. Parasite cells treatment of malaria,
that have developed particularly malaria caused by
resistance can drain P. falciparum, which is a highly
chloroquine at 40x the rate of deadly infection. However, it is
a cell without chloroquine also clear that resistance to
resistance. chloroquine is becoming more
widespread across the world
In places where chloroquine with many countries opting to
resistance has not yet been use other treatments such as
discovered amongst P. artemisinin combination
falciparum, chloroquine is still therapy (ACT) as the first-line
shown to be highly effective as drug for the treatment against
a form of treatment. From P. falciparum. I believe that it
2008-9, a study was carried is necessary for countries (at
out in the municipality of high risk especially) to be
Puerto Lempira, Gracias a Dios, ready to use ACT if they are
Honduras, in order to evaluate not already using it, as the
the use of chloroquine. A total WHO advises ACT to be used in
of 68 patients from ages 6 areas where chloroquine-
months to 60 years of age resistant P. falciparum are
completed the entire trial and present [12]. Small outbreaks of
each patient was positive for
malaria due to P. falciparum
according to light microscopy.
Each patient was given a dose
of chloroquine of varying sizes
over the first 3 days,
depending on their body
weight. Patients received
supervised treatment until day
28. The data showed that the
parasite density in most
patients had dramatically
decreased by day 3 and by day
7 all patients were parasite
negative (shown by no
detected asexual stages in the
blood) [11].
Chloroquine can have several
side effects on the body,
including nausea, vomiting,
headaches and diarrhea. It also
has several interactions with
other drugs, which may be of
20THE WILSON’S INTRIGUE | BIO-CHEMISTRY Issue 5 | April 2021
What is the Effectiveness of the Use Of Antibodies when Treating
Paediatrics Patients with Mild/Severe, Acute/Chronic Asthma
Exacerbation?
By Junayd Soobratty (Y12)
A
n asthma exacerbation is distinguished part of the immune system produced in the bone
by the swelling or inflammation of the marrow. However, high levels of eosinophils can
airway [1]. Respiratory difficulties are cause inflammation in the airways, affecting the
caused due to the narrowed bronchial sinuses and nasal passages as well as the lower
tubes. The word exacerbation (more commonly airways [5]. The majority of asthmatic conditions
referred to as an attack) denotes the event can be controlled with conventional treatment
caused by a trigger such as an allergen leading such as inhaled corticosteroids (ICS) appropriate
to the airways constricting. Triggers may for their severity. However, some types of
include, animal fur, pollen, dust or exercise asthma, known as ‘refractory asthma’ which is
where the trachealis muscles contract, when the patient experiences persistent
producing more than standard levels of mucus. symptoms, frequent asthma attacks or low lung
Asthma is the most common obstructive function despite taking asthma medications as
pulmonary disease in children affecting one in they do not respond to high doses of this
eleven in the UK [2]. conventional treatment. Some refractory
An asthma exacerbation can be categorised in asthma patients have to take oral steroids such
two main ways which can further be subdivided as prednisone to manage their asthma.
into six classifications [3]: In general:
A) Intermittent asthma Short-term treatments [6]:
1) Mild intermittent asthma: where the • Short-acting beta-agonists; first choice for
paediatric patient will only experience quick relief of asthma symptoms as they
slight tightness of the airways on rare are used as muscle relaxants so decrease
occasions the contraction on the trachea by the
2) Moderate Intermittent asthma: where the Musculus trachealis
asthmatic will feel some respiratory • Anticholinergic agents; acts swiftly to
distress in exceptional cases instantly relax airways
3) Severe intermittent asthma: where the • Oral and intravenous corticosteroids;
person would feel significant tightness of relieve airway inflammation but can cause
the chest and pain sporadically serious side effects when used long term
B) Persistent asthma Treatment used in long-term:
1. Mild persistent asthma: where the person • Inhaled corticosteroids; the most effective
would be wheezing or whistling when long-term control medicine usually
breathing, with slight swollen airways; • Inhaled long-acting beta-agonists; open
symptoms occur more than twice a week the airways by relaxing the smooth
but less than once a day muscles around them
2. Moderate persistent asthma: wheezing to • Combination inhaled medicines; an inhaled
an extent of murmured speech, coughing, corticosteroid along with a long-acting
swollen airways, development of mucus in beta-agonist
the airways, some chest tightness or pain; • Biologics; target a cell or protein in the
experience asthma symptoms every day body to prevent airway inflammation
3. Severe persistent asthma: where the • Long-acting bronchodilators; possibly
paediatric patient will feel significant tiotropium (Spiriva) along with
respiratory distress. There may be a corticosteroids even though daily inhaled
display of nasal flaring and paradoxical steroid is taken. Long-acting
thoraco-abdominal movement; experience bronchodilators alone as a long-term
asthma symptoms every day and at least asthma treatment is ineffective as it does
one night per week [4]. not prevent and has short term effect for a
Key characteristics of an asthmatic paediatric long-term use
patient is the reversible airway obstruction,
airway hyper-responsiveness and chronic airway
inflammation typically with eosinophil
infiltration. Eosinophilic asthma involves
abnormally high levels of a particular type of
white blood cell called eosinophils which are
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