6. Insect circulatory system

6. Insect circulatory system


The roles of the circulatory system are
to transport essential metabolites from the fat body to the cells, carry waste
to the excretory system and provide immunity to harmful organisms. Insects have a simple open circulatory system. The circulatory system consists of a dorsal vessel running the length of the body. The dorsal vessel is divided into a posterior heart that contains intake valves called ostia and an anterior aorta The open space of the body is called the
hemocoel. The hemocoel is filled with insect blood called hemolymph. Since insect hemolymph does not transport oxygen, it does not contain hemoglobin and, therefore, lacks the red color that is characteristic of blood from
vertebrate animals. Hemolymph is pumped forward by the heart through the aorta, into the head and flows back through the body in the open hemocoel. Hemolymph re-enters the posterior heart through the ostial valves, and the cycle repeats. The hemocoel is always full of hemolymph, and the heart ensures it’s mixing. Auxilary, pulsatile hearts at the base of the antenna legs and wings pump hemolymph into those appendages.

Researchers tackle deadly blood infections

Researchers tackle deadly blood infections


(instrumental music) – [Narrator] Blood stream
infections, or sepsis, can be difficult to diagnosis and treat. And antibiotics appear to
be becoming less reliable in managing some of them. The University of Michigan Health System is utilizing a multidisciplinary approach to learn better ways to
diagnose and treat sepsis. Blood stream infections are infections that typically begin in
a local part of the body, say in the bladder or
in the skin or the lung, and then the bacteria that
caused those infections managed to, sort of, break
free from the usual defenses and make it into the bloodstream. And that gives the bacteria
an opportunity to go, essentially anywhere it wants. And once it’s in the
bloodstream it can travel to distant organs, it
can travel to the brain, it can travel to the heart. And it’s basically, sort
of, a horse out of the barn. Bloodstream infections are a problem because most of the defenses
that your body has built up to fight infections, are defenses that were built
against things like splinters and wound infections, and
you know, sore throats, and bladder infections, things like that. They’re defenses that
were built to go somewhere to do a thing. They’re a local defense. And the problem with bloodstream
infections is that it, when a bacteria is allowed to go anywhere, it has an opportunity
to rewrite the rules. And now defenses that were
local and designed to be local are suddenly being deployed everywhere. The standard treatment
for bacterial infections of the bloodstream or
elsewhere, are antibiotics. And what’s clear from the last 50 years, and antibiotics have
really only been around for about 50 years, is that they’re becoming
less and less reliable for taking care of infections. And so what we’re looking for, are ways of treating the disease and helping along the
host defense in such a way that doesn’t require antibiotics. And one of the ways that
we’re looking to do that, is we’re looking to find a
strategy to improve the ability of the bloodstream to
filter these things out. How can you get them out of
the bloodstream even faster? Are there mechanical
tricks that you can play on the bacterium that
don’t require antibiotics that will allow the body to grab it, pull it out of the bloodstream and resolve the infection faster. One of the things we’re
trying to understand are the rules for how bacteria
traffic in the bloodstream, and if you understand the
timing of those events you might be able to better understand how best to detect the
bloodstream infection when it’s present. That’s the first issue. The second thing that we’re working on, are looking for ways to
just fundamentally change the rules of engagement between
the bacteria and the host. There are mechanical features at play, in terms of getting these
bacteria and flowing blood out. If we can change the
mechanics of that event, then we can potentially have
a therapy that the bacteria doesn’t really have an
opportunity to defend against. That it doesn’t have the ability to develop a resistance against, and potentially can be a useful therapy. (instrumental music)

Immune System: Innate and Adaptive Immunity Explained

Immune System: Innate and Adaptive Immunity Explained


Our body has a powerful army that protects it from various types of threats. These threats can come in the form of mechanical injuries, the entry of germs, or the entry of other foreign particles like dust. This personal army is called the immune system. Every day, we encounter a huge number of bacteria, viruses and other disease-causing organisms. However, we don’t fall ill every other day. which is due to our immune system – an army of cells that is always roaming our body, ready to ward off any attack. The immune system can be broadly divided into
two parts – innate and adaptive immunity. Innate immunity or non-specific immunity is
the body’s first natural defense to any intruder. This system doesn’t care what it’s killing. Its primary goal is to prevent any intruder
from entering the body, and if it does enter, then the immune system kills this intruder. It doesn’t differentiate between one pathogen
and another. The first component of this defensive system
is your skin. Any organism trying to get into the body is
stopped by the skin, our largest organ, which covers us. Secondly, there is the mucous lining of all
our organs. The sticky, viscous fluid of this lining traps
any pathogens trying to get past it. These are the physical barriers. However, we also have chemical barriers, such
as the lysozyme in the eyes, or the acid in the stomach, which kill pathogens trying to
gain entry. The genitourinary tract and other places have
their own normal flora, or microbial community. These compete with pathogens for space and
food, and therefore also act as a barrier. The next line of defense is inflammation,
which is done by mast cells. These cells are constantly searching for suspicious
objects in the body. When they find something, they release a signal
in the form of histamine molecules. These alert the body, and blood is rushed
to the problem area. This causes inflammation and also brings leukocytes,
or white blood cells, which are soldiers in our body’s cellular army. Once they come, all hell breaks loose! Sometimes however, the intruder may not be
germ, but rather a harmless thing like a dust particle. The body still causes a full immune reaction to this intruder, which is how allergic reactions occur. In the fortress of our body, the leukocytes
are VIPs. They have an all-access pass to the body,
except, of course, to the brain and spinal cord. Our leukocytes come in many types. Those that belong to the innate system are the phagocytes. These cells can either patrol your body, like the neutrophils, or they can stay in certain places and wait for their cue. Neutrophils are the most abundant cells. They patrol the body and can therefore get
to a breach site very quickly. These cellular soldiers kill the infectious
cell and then die, which leads to pus formation. There are also the big bad wolves, or the
macrophages. These cells are like hungry, ravenous monsters
who simply engulf unwanted pathogens. Instead of roaming freely in our blood, they
are collected in certain places. These cells can consume about 100 pathogens
before they die, but they can also detect our own cells that have gone rogue, such as
cancer cells, and kill them too. Beyond that, we also have the Natural Killer
Cells. These cells can efficiently detect when our
own cells have gone rogue, or are infected with, say, a virus. NKCs detect a protein produced by normal cells,
called the Major Histocompatibility Complex or MHC. Basically, whenever a cell isn’t normal, it
stops producing this protein. The NKCs move around constantly, checking
our cells for this type of deficiency, and when they find an abnormal cell, they simply
bind to it and release chemicals that will destroy it. The last cells of our innate immune system
are the dendritic cells. These are found in places that come in contact
with the outside environment, such as the nose, lungs, etc. They are the link between our innate and adaptive immune systems. They eat a pathogen, and then carry information about it to our adaptive immune system cells. This information is produced and shared in
the form of antigens. Antigens are the traces that pathogens leave
around. They are molecules found on the surface on
pathogens that can be detected by our adaptive immune system for recognition. The dendritic cells pass on this information
to our T cells. However, macrophages can also perform this
function. Now, there is also the adaptive or acquired
immune system. This system is more efficient, as it can differentiate
between different types of pathogens. It has 2 main components – T lymphocytes and
B lymphocytes. T-cells come into play when an infection has
already occurred, thus bringing about the cell-mediated immune response. B-cells join the fight when the pathogens
have entered, but haven’t yet caused any disease. This is called the humoral immune response. Some T-cells take signals from the dendritic
cells or macrophages, and are thus called helper T-cells. They perform two key tasks: forming effector
T-cells, which are basically cells that cycle through the body and call in the cavalry,
namely other white blood cells. Helper T-cells also form memory T-cells, which
keep a record of this antigen for future reference. Sometimes, the some cells of our body know
that they have lost the battle. Essentially, the affected area or organ has
They have become heavily infected with pathogens, so there is no hope for them. At this point, the immune system brings out
the cytotoxic t cells. These cells rush over and perform a mercy
killing for the infected and dying cell. Furthermore, we have the B-cells. They produce chemicals called antibodies,
which fit on the antigens of pathogens, much like how a lock and key fit together. These antibodies crowd around a pathogen and
act like tags. They signal the macrophages to come and kill
the marked pathogen. B-cells also produce memory B-cells when they
encounter an antigen. The B- and T- memory cells jointly maintain
a record of all encountered infections, and thus strengthen and solidify the body’s
immune response to these infections. Our innate immune response is quicker, though
non-specific. It gets into action within hours and is pretty
strong. However, when things get out of hand, the
innate system calls for help from the acquired immune system. This system can take days to mount a response,
but the next time we encounter that pathogen, it won’t make us get sick. In short, every day that we spend being healthy is all thanks to our immune system. So, it definitely deserves our respect.

How can research save lives from the Ebola epidemic in the Democratic Republic of Congo?

How can research save lives from the Ebola epidemic in the Democratic Republic of Congo?


One of the deadliest diseases on the planet has been recurring in
central Africa since the 1970s – ever more frequently. It was first identified near
the eponymous Ebola river and kills 30-80% of those it infects. Ebola can never be eradicated – it’s endemic in animals of
the forests of central Africa in most of which it causes no symptoms. People may come into contact with blood,
urine or saliva of animals in the forest or whilst hunting, but the main hosts
are thought to be bats, which are often eaten as bushmeat. From them, the virus spreads between
people through bodily fluids. Initially, we humans experience
flu-like symptoms as the virus evades the immune system,
preventing immune cells identifying it. Without these immune guards,
the virus can enter many cells and replicate rapidly
whilst the body is defenceless. The virus damages many
types of cell when it invades – including those in the liver
which control blood clotting. The body is overwhelmed, with the virus
triggering a strong immune response, inducing uncontrolled inflammation. This causes many tiny
blood vessels to leak. Because the blood can’t clot, when these vessels leak,
bleeding results – internally, and sometimes externally,
from the eyes, ears and nose. This loss of blood and
widespread damage to cells stops the body’s vital organs working. The only way to survive is to keep the organs functioning
by replacing lost blood through transfusions
and intravenous fluids, keeping the patient alive
throughout the onslaught long enough for the immune system
to develop antibodies to the virus. Even if you survive, the virus can remain
in areas such as the eyes and testes, which can leave people infectious
for more than a year after recovery. Because there is currently no cure, getting ahead involves
preventing people getting ill – through containment of those
infected with the disease and the development of vaccines. Countries which have not
experienced an Ebola outbreak tend to have low public and clinical
awareness around the disease, as well as poor diagnostic tools, meaning the alarm may only be raised
once the disease has spread widely. Many people may become infected, with containment made more difficult
by inadequate health infrastructure. As a result of such conditions, the 2014
West Africa epidemic lasted for two years, affected eight countries, and more than 11,000 people died. There are six known Ebola species. Four of which cause disease in humans. These differ in the nature
of their surface proteins and are recognised differently
by our immune cells. This makes many different
targets for vaccines. A vaccine against the deadliest and most common
– the Zaire species – has been developed. But it takes years of field testing for
a vaccine like this to be officially approved. Developing a vaccine that can target all the species
that cause disease in humans would be ideal. Identifying the Ebola species and implementing drug trials and
vaccinations as soon as possible is why genomic sequencing of
all human occurrences of the virus needs to be part of the Ebola
outbreak emergency response. By tracing the evolution of the virus, genomic sequencing allows scientists to
locate who caught the disease from who, identifying transmission
routes and potential contacts. As viruses also keep changing and mutating,
they are also moving targets. Vitally, genomic sequencing allows us to know
which parts of the virus are preserved, which parts are integral to its function
and good targets for vaccines. In future, we may even be able to develop vaccines
which act against multiple species at once. Research funded by Wellcome and
others during the West Africa crisis allowed the first Zaire-species
vaccine to be trialled. It successfully protected
against the Ebola virus. This vaccine was stockpiled
ready for later use on health workers and potential contacts of
those with the disease. When an outbreak arose in 2018
in the Democratic Republic of Congo, Wellcome donated 2 million pounds,
partly to support a vaccination programme for all those who may have come into
contact with those with the disease – in this case upwards of 3,000 people. The rapid release of emergency funds enabled not just containment and care, but also scientific research to be incorporated
throughout the emergency response – crucial to progress in combatting the disease. Only because this response was
well-practised and coordinated, was it possible for help
to be quickly assembled and to implement international policies,
such as border checks. Although the DRC’s May 2018 outbreak was stamped out within weeks,
and 33 people died, a new appearance of Ebola in an active
conflict zone in a different part of the country demonstrated the enduring
nature of the threat. Such situations add complication
to the outbreak response, but the international community is
now better-equipped to combat Ebola. So by keeping the pressure up
on the scientific research, in the lulls between clear
and present dangers, we can get ahead of the threat
simmering below the surface and contain Ebola’s
next inevitable incursion.

First Aid for Insect Bites : How to Treat a Yellow Jacket Sting on Someone Who is Allergic

First Aid for Insect Bites : How to Treat a Yellow Jacket Sting on Someone Who is Allergic


Few things can cause the amount of fear and
discomfort that come with an allergic reaction from a yellowjacket sting. Hi, I’m Captain
Joe Bruni. Now what I’m going to talk about is how to deal with and treat the allergic
reaction to a yellowjacket type of sting. Yellowjackets will leave some type of stinger
in the area that must be removed with the backside of a credit card or dull object like
the backside of a butter knife. Scrape the stinger away from the skin to keep from further
injecting any toxin into the body. The allergic reaction known as anaphylacsis will surface
by hives forming on other areas of the body, a swelling of the face, tongue our throat,
and also difficulty in breathing, and in sever cases a loss of consciousness. If the person
has an epi-pen because they know they’re allergic to yellowjackets, help this individual administer
the epinephrine through the device known as the epi-pin into the thigh area. If the person
is showing signs of an allergic reaction, and is not aware that they have an allergy
towards yellowjackets, if possible administer some type of oral antihistamine and then transport
to a medical facility. Few things can be as scary as an anaphylactic reaction. Knowing
the proper steps to take can help with a positive outcome when dealing with an allergic reaction
to yellowjackets. I’m Captain Joe Bruni, stay safe and we’ll see you next time.

First Aid for Insect Bites : How to Treat a Brown Recluse Spider Bite

First Aid for Insect Bites : How to Treat a Brown Recluse Spider Bite


You know, one of the common insect bites that
can be very frustrating to deal with is that of the brown recluse spider. Hi, I’m Captain
Joe Bruni, and what I’m going to talk about is how to treat the bite that has occurred
from the brown recluse spider or fatal back spider. The brown recluse spider will form
some type of reddening area or possibly some type of pussy, pustule area followed by necroses
of some tissue after a brown recluse spider bite. Apply some type of antiseptic cream
or lotion to the bite area and then apply ice or a cold pack in intervals of twenty
minutes on, twenty minutes off to reduce swelling and pain. It would also be advisable to take
some type of pain reliever like Ibuprofen and not aspirin, as aspirin will thin the
blood. And then seek medical attention. If the pustule forms do not pop it or break it.
However, if it breaks on its own, re clean the area with soap and water, and antiseptic
as you seek medical attention. I’m Captain Joe Bruni. Stay safe, and we’ll see you next
time.

CSI Special Insects Unit: Forensic Entomology


Here’s a fascinating niche science that, if you ask me, we should see on prime-time TV way more often: forensic entomology, the study of insects and arthropods used in legal investigations. As it turns out, there are lots of cool ways insects can help us solve crimes. Fair warning, though: you may not want to watch this one over lunch! [music/intro] The field of forensic entomology is
actually pretty broad and is commonly divided up into three general areas: urban, stored product, and medico-legal. The urban specialty focuses on insects in human dwellings. Scientists who do this kind of work
could surely tell you all kinds of amazing things about what goes on in
your kitchen cabinets at night, but as forensic experts, they specialize in
investigating both civil and criminal cases helping in lawsuits involving, say, damages from a cockroach or bed bug infestation. Stored product entomology, meanwhile, usually deals with the contamination of commercial products, like if you find a
family of dead ants in your fast food burrito, or a bunch of moth wings in your candy bar, or spiders in your toilet paper roll. But
the medico-legal area is the most flashy, popularized part of the field. It’s what you might see on an episode of CSI and it often involves reading the signs of blood sucking or carrion-feeding
insects at violent crime scenes typically involving murder, suicide, abuse, and neglect. At a fresh crime scene, for example, forensic entomologist would know that tiny flecks of what look like spattered blood could actually be the prints of roaches
or flies that had walked through blood elsewhere at the scene. These experts can even match human DNA from the blood found in blood feeding insects, living or dead. One murder case in Italy was solved when investigators scraped a blood filled mosquito off the wall in a
suspect’s house and found it contained the blood of the victim. Take that, bad guys! Crime-solving, bug-loving scientists are also often called upon to help estimate a victim’s time of death. A dead body goes through a whole series of phases from putrefaction and
fermentation to dry decay and skeletonization, and each phase attracts different life
stages and types of insects. Forensic entomologists use this rotating cast of critters to help determine a body’s death in a couple of ways usually involving larval development and species succession. The larval development technique studies the size and
prevalence of maggots and other larva and is usually useful if the body is less
than a month old. If the corpse is older, it’s best to use the species succession
method. For example, blow flies are great quickly discovering dead meat because they like their food fresh and full of fluids, so determining what phase they’re in can often provide the most accurate estimates for time of death, but as the flesh dries out the blow flies
take off just as other species like the coffin fly arrive in force. Once the corpse is too dry for even
maggots, all the flies clear out. Then beetles often roll in. Some species like hide and carrion beetles have robust mouth parts they can work on the remaining
dried flesh and ligaments. Mites and moth larvae round out the final cleaning crew, consuming the remaining hair and leaving only a skeleton. So thanks to all the insects out there and
the scientists who study them for solving crimes and doing a job I would rather not do! And thanks for
watching this SciShow Dose especially to all of our subscribers on Subbable who make this whole channel possible. Did you know that you can be an honorary associate
producer of SciShow or even pick the topic for one of our episodes? To find out how you can go to subbable.com/scishow and you can always find us on Facebook and Twitter and if you want to keep getting smarter with us, don’t forget to go to youtube.com/scishow and subscribe! [music]

HUGE, INFECTED INGROWN TOENAIL + GRANULOMA REMOVAL


And, Action! today we’re here with Dr. Martin
we’re helping him out he’s had a little injury so we’re
gonna go ahead and proceed with another partial nail avulsion I’d like for you guys
come close we have an ingrown nail also known as a paronychia he has developed this pyogenic granuloma once again it’s a hyper-granulation piece of
tissue as a result of the ingrown nail the body actually creates that alone and
and I can rest assure that there is a very large piece of nail in
there and we’re gonna go ahead and we’re going to take this amount of the nail
out to make sure that this does not occur again it is very important these are very uncomfortable
what we’re gonna do first is we’ll just kind of lift everything up just check on
the patient is everything okay if feel any discomfort just please let us
know I’ll take our English anvil there’s other
podiatrists that will use other techniques there’s a couple of different
techniques just to get all the way back there but we have to be very, very
careful with the nail root go underneath the pyogenic granuloma this is a very large nail so basically
what we’ve done is this piece of nail as everyone can see this is
all the way back all the way back underneath the the proximal nail fold I’m gonna go ahead and check to make
sure four-by-four and the english anvil
again please sorry about that, sir we cannot leave any pieces behind if we’d leave any pieces behind
that’s not gonna be a good thing so now we’re gonna go to
the second part of the procedure as everyone can tell we have
this flap of skin of red tissue which is the pyogenic granuloma we can use this we can use a blade and I’m just going to show you guys here it’s kind of attached we’re not going to take a whole lot we’ll start from here
these pyogenic granulomas are very vascular and as everyone will see
there’s gonna be a quite a significant amount of blood here okay we’re gonna go
ahead and cut some more out and cut this out we’re not cutting the
healthy skin we’re only cutting away [the granuloma] just dry this up a little bit here so I just want everyone to see here this has been a clearly a relatively complex
ingrown nail this is part of the root of the pyogenic granuloma we’re
not gonna go ahead and remove that we’ve removed the entire ingrown nail which was actually just embedded into this nail fold and this is
actually silver nitrate silver nitrate is used to chemically cauterize which
means to stop the bleeding and we’ll go ahead and just kind of place that in
there I like to put a little bit of pressure there it turns white because
it is a reaction and again the purpose of the silver nitrate is to actually stop the bleeding these granulomas will bleed and
bleed and continue to bleed there’s still a little bit of bleeding here on
the side and again with time all this discoloration will disappear leave that there for
about five seconds and that should do it super it is extremely important especially for
diabetic patients for patients with vascular disease or patients from all
walks of life these ingrown toenails need to be
treated properly to make sure that there are no long-term complications he’s going to be very happy and so are we if you guys have any questions always
feel free to reach out to us at www.jawspodiatry.com thanks for watching

DHS investigating bloodstream bacterial infection

DHS investigating bloodstream bacterial infection


SHE STAYED ON THE SCENE, AND THEY DO NOT THINK SHE WAS IMPAIRED. KATHY: THANKS. WE’RE FOLLOWING A DEVELOPING STORY. STATE HEALTH OFFICIALS ARE INVESTIGATING A DEADLY OUTBREAK OF BLOODSTREAM INFECTIONS, AND THEY DON’T KNOW THE SOURCE. THE BACTERIA CALLED ELIZABETHKINGIA HAS BEEN FOUND IN 44 PATIENTS IN SOUTHEAST AND SOUTHERN WISCONSIN SINCE NOVEMBER. ALL PATIENTS HAVE HAD UNDERLYING HEALTH CONDITION MOST WERE OVER 65 YEARS OLD. EIGHTEEN HAVE DIED. THE STATE RELEASED A STATEME READING, “DETERMINING THE SOUR OF THE BACTERIA AFFECTING PATIENTS IN WISCONSIN IS A COMPLEX PROCESS. WHILE WE RECOGNIZE THERE WILL BE MANY QUESTIONS WE CANNOT YET ANSWER WE FEEL IT IS IMPORTANT , TO SHARE THE LIMITED INFORMATION WE HAVE ABOUT THE PRESENCE OF THE BACTERIA AS WE CONTINUE OUR WORK TO DETERMINE TH SOURCE.” IN 2011, A HARTLAND COMPANY RECALLED MEDICAL PRODUCTS AFTER THE FDA FOUND THE PRESENCE OF THE SAME BACTERIA. U.S. MARSHALS RAIDED THE PLANT