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Another inflammatory mediator, bradykinin , contributes to edema , which occurs when fluids and leukocytes leak out of the bloodstream and into tissues. It binds to receptors on cells in the capillary walls, causing the capillaries to dilate and become more permeable to fluids.

  • What do the three complement activation pathways have in common?
  • Explain autocrine, paracrine, and endocrine signals.
  • Name two important inflammation-eliciting mediators.

Part 2

To relieve the constriction of her airways, Angela is immediately treated with antihistamines and administered corticosteroids through an inhaler, and then monitored for a period of time. Though her condition does not worsen, the drugs do not seem to be alleviating her condition. She is admitted to the hospital for further observation, testing, and treatment.

Following admission, a clinician conducts allergy testing to try to determine if something in her environment might be triggering an allergic inflammatory response. A doctor orders blood analysis to check for levels of particular cytokines. A sputum sample is also taken and sent to the lab for microbial staining, culturing, and identification of pathogens that could be causing an infection.

  • Which aspects of the innate immune system could be contributing to Angela’s airway constriction?
  • Why was Angela treated with antihistamines?
  • Why would the doctor be interested in levels of cytokines in Angela’s blood?

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[link] provides a summary of the chemical defenses discussed in this section.

Chemical Defenses of Nonspecific Innate Immunity
Defense Examples Function
Chemicals and enzymes in body fluids Sebum from sebaceous glands Provides oil barrier protecting hair follicle pores from pathogens
Oleic acid from sebum and skin microbiota Lowers pH to inhibit pathogens
Lysozyme in secretions Kills bacteria by attacking cell wall
Acid in stomach, urine, and vagina Inhibits or kills bacteria
Digestive enzymes and bile Kill bacteria
Lactoferrin and transferrin Bind and sequester iron, inhibiting bacterial growth
Surfactant in lungs Kills bacteria
Antimicrobial peptides Defensins, bacteriocins, dermicidin, cathelicidin, histatins, Kill bacteria by attacking membranes or interfering with cell functions
Plasma protein mediators Acute-phase proteins (C-reactive protein, serum amyloid A, ferritin, fibrinogen, transferrin, and mannose-binding lectin) Inhibit the growth of bacteria and assist in the trapping and killing of bacteria
Complements C3b and C4b Opsonization of pathogens to aid phagocytosis
Complement C5a Chemoattractant for phagocytes
Complements C3a and C5a Proinflammatory anaphylatoxins
Cytokines Interleukins Stimulate and modulate most functions of immune system
Chemokines Recruit white blood cells to infected area
Interferons Alert cells to viral infection, induce apoptosis of virus-infected cells, induce antiviral defenses in infected and nearby uninfected cells, stimulate immune cells to attack virus-infected cells
Inflammation-eliciting mediators Histamine Promotes vasodilation, bronchoconstriction, smooth muscle contraction, increased secretion and mucus production
Leukotrienes Promote inflammation; stronger and longer lasting than histamine
Prostaglandins Promote inflammation and fever
Bradykinin Increases vasodilation and vascular permeability, leading to edema

Key concepts and summary

  • Numerous chemical mediators produced endogenously and exogenously exhibit nonspecific antimicrobial functions.
  • Many chemical mediators are found in body fluids such as sebum, saliva, mucus, gastric and intestinal fluids, urine, tears, cerumen, and vaginal secretions.
  • Antimicrobial peptides (AMPs) found on the skin and in other areas of the body are largely produced in response to the presence of pathogens. These include dermcidin, cathelicidin, defensins, histatins, and bacteriocins.
  • Plasma contains various proteins that serve as chemical mediators, including acute-phase proteins , complement proteins , and cytokines .
  • The complement system involves numerous precursor proteins that circulate in plasma. These proteins become activated in a cascading sequence in the presence of microbes, resulting in the opsonization of pathogens, chemoattraction of leukocytes, induction of inflammation, and cytolysis through the formation of a membrane attack complex (MAC) .
  • Cytokines are proteins that facilitate various nonspecific responses by innate immune cells, including production of other chemical mediators, cell proliferation, cell death, and differentiation.
  • Cytokines play a key role in the inflammatory response, triggering production of inflammation-eliciting mediators such as acute-phase proteins, histamine , leukotrienes, prostaglandins , and bradykinin .

Fill in the blank

________ are antimicrobial peptides produced by members of the normal microbiota.

bacteriocins

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________ is the fluid portion of a blood sample that has been drawn in the presence of an anticoagulant compound.

plasma

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The process by which cells are drawn or attracted to an area by a microbe invader is known as ________.

chemotaxis

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Short answer

Differentiate the main activation methods of the classic, alternative, and lectin complement cascades.

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What are the four protective outcomes of complement activation?

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Questions & Answers

it is the main memory of a person.
Kizza Reply
what is brain
Tope Reply
is the main memory of a person.
Kizza
it is the centre of the nervous system found in all vertebrates and most invertebrates.
Akhiomo
what are the two acids the skin produce
Caro Reply
alpha hydroxy and beta hydroxy there are water soluble compounds and often use as exfoliant
Enow
what must a positive strand of an RNA virus do first
Kelsi-Ann Reply
A positive-sense single-stranded RNA virus (or (+)ssRNA virus) is a virus that uses positive sense single stranded RNA as its genetic material. Single stranded RNA viruses are classified as positive or negative depending on the sense or polarity of the RNA.
Dejene
 The positive-sense viral RNA genome can serve as messenger RNA and can be translated into protein in the host cell. Positive-sense ssRNA viruses belong to Group IV in the Baltimore classification. Positive-sense RNA viruses account for a large fraction of known viruses, including many pathogens
Dejene
such as the hepaci virus C, West nail virus, dengue virus, SARS and MERS coronaviruses, and SARS-CoV-2 as well as less clinically serious pathogens such as the rhinoviruses that cause the common cold.
Dejene
Why strong acid and alkline are not harmful to mycobacterium bacili?
Brian
What are the types of bacteria
John Reply
Do you mean the shapes or the the two different types of bacteria? Bacteria are often described in terms of their general shape. Common shapes include spherical (coccus), rod-shaped (bacillus), or curved (spirillum, spirochete, or vibrio) The two different types are gram negative or gram positive.
Melanie
what other characteristics of prokaryotes a bacteria don't have?
Brian
Prokaryotes are single-celled organisms belonging to the domains Bacteria and Archaea. Prokaryotic cells are much smaller than eukaryotic cells, have no nucelus, and lack organelles. All prokaryotic cells are encased by a cell wall. Many also have a capsule or slime layer made of polysaccharide.
Dejene
gram positive bacteria and gram negative bacteria
mubeen
Most bacteria can be broadly classified as Gram positive or Gram negative. Gram positive bacteria have cell walls composed of thick layers of peptidoglycan.cells stain purple when subjected to a Gram stain procedure. Gram negative bacteria have cell walls with a thin layer of peptidoglycan.
Dejene
all of you are amazing microbiologists
demisew
thanks demisew....
Dejene
guys what are the two acids the skin produce
Caro
what are the bacteria's involved in the decaying of food
Enow Reply
Some pathogenic bacteria, such as Clostridium perfringens and Bacillus cereus, are capable of causing spoilage.
Dejene
Corona has a gray and black cell structure ....if yes explain..if no explain
Joshua Reply
multiple questions and answers in microbiology and bio chemistry
Lakshmi Reply
is the study of a bacteria and other organisms
isir
yes..this book is about bacteria & others organisms
Hasan
biochemistry is the branch of science that dealing of chemical compounds reactions and other processes
isir
have you any question?
Hasan
yess, Why scientists not search coronavirus vaccines in short time.
demisew
they are on
Monyditchol
what are the symptoms for tuberculosis
Chiamaka
Most people infected with the bacteria that cause tuberculosis don't have symptoms. When symptoms do occur, they usually include a cough (sometimes blood-tinged), weight loss, night sweats and fever.
Dejene
symptoms tuberculosis. Fever Chills Night sweats Cough Loss of appetite Weight loss Blood in the sputum (phlegm) Loss of energy
lourdes
can corona virus transmitted from mother to her child through placenta ?
Abdul
probably
Mad
no
Oke
no,but it can through trait
Falere
mutation occur in the genome of corona virus. thats why the corona vaccines forming just difficult
Muzamil
intersted
Do
no
Esther
No
John
Yes
Suhaib
yes
Benjamin
yes coz it's spread through the soft body parts more so the openings in our bodies
Rebecca
Yes
Ayan
what is relation between fear (from covid 19 ) and immune sys ?
Abdul
because it damages the immune system by reduction the action of WBC
mike
reducing pls
mike
how is it possible for a woman to be pregnant and still See's her period
Prince Reply
we term it as discharge
Monyditchol
what is immunity
evans Reply
What is a varuis
evans
A submicroscopic infectious organism, now understood to be a non-cellular structure consisting of a core of DNA or RNA surrounded by a protein coat. It requires a living cell to replicate, and often causes disease
Ebo
A virus is a biological agent that reproduces inside the cells of living hosts. When infected by a virus, a host cell is forced to produce thousands of identical copies of the original virus at an extraordinary rate
Dejene
A virus is a microorganism which invade our bodies causing diseases due to eliciting immune responses by the body against it, can replicate using our genome inducing production of proteins helping them to establish new life inside our bodies.
What are the important of capsules
Marriam Reply
what are the roles of male sex hormones
Marriam
Testosterone is the principal sex hormone inmales and is produced in the testes (testicles). Dihydrotestosterone is a hormonein which the double bond of testosterone has been reduced by enzyrne reactions in the body. ... The testes perform two functions: They produce sperm, and they producetestoster
Dejene
Capsules in bacteria protect them from phagocytosis of eukaryotic organisms. This is what makes them virulent and harmful without antibodies.
Lewis
any one told me definition of amoebic dysentery & amoebic liver dysentery?
Mira
Amoebiasis, also known amoebic dysentery, is an infection caused by any of the amobae of the Entamoeba group. Symptoms are most common during infection by Entamoeba histolytica. Amoebiasis can be present with no, mild, or severe symptoms. Symptoms may include abdominal pain, diarrhea....
Dejene
tnx
Mira
u welcome mira
Dejene
people explain for me this words in public health.tb prevention 1:promotive 2:preventive 3:curative 4:rehabilitative
Obrian
Capsules function similarly to endospores they provide an extra layer of protection especially in acidic or basic environments. It is also a thicker membrane which can change the osmosis process and can provides resistance to antibotics depending if it is gram negative or positive.
Melanie
...As some antibotics focus on breaking down the cell wall and is not able to.
Melanie
what are the clinical classification of amoxicillin?
Rebecca
how does a autoimmune diso ders develop
Oliver Reply
simply autoimmune disease is not completely understood. There are many variations from genetically inherited to acquired by viruses like HIV. Genetically they may not be prominent until an unknown point in one's life. I am far from an expert, I am just reciting what I have learned. Take rheumatoid
Lewis
what is anatomy
Mohamed Reply
Anatomy is the study of parts of the human body
Matilda
the branch of science concerned with the bodily structure of humans, animals, and other living organisms, especially as revealed by dissection and the separation of parts.
Dejene
Describe the halden effect
Suleiman
The Haldane effect is a property of haemoglobin first described by John ScottHaldane. Oxygenation of blood in the lungs displaces carbon dioxide from hemoglobin which increases the removal of carbon dioxide. This property is the Haldane effect.
Dejene
Difference between chief cells and parietal cells in the stomach
Suleiman
 Parietal cells are the epithelialcells that secrete HCl and intrinsic factor. They are located in the gastric glands found in lining of fundus and stomach. The gastric chief cells , are cells in the stomach that release pepsinogen and chymosin.
Dejene
is the study of structure and organs located in human life
isir
listen to Matilda
Lewis
essay on microbiology and how it contribute to the pharmacy assistant programme
Tagedevi Reply
I want to know how it contribute to the pharmacy assistant programme
chidiebube
Contribute how? If you want to contribute to pharmaceutical stuff you should look for websites with blogs that relate to your interests.
Lewis
hello i want to know how it contribute to microbiology programs
Dejene
Microbiology is the study of bacteria and and organisms such as viruses, fungi, and mold. How does this apply to medicine? It applies to medicine or pharmacology because when you get sick you are infected by a pathogen and understanding how these organisms interact with each other helps you to....
Melanie
develop medicine. A lot of bacteria infections can be cured with various medicines but not all medicines work equally. It depends if your sickness is based on gram positve or negative bacteria, if its s mold or fungus or a virius. Each medicine targets a certain one.
Melanie
If you need any ideas I recommend looking up Louis Pastar who used microbiology to invent a lot of medicines and contributed greatly to microbiology and pharmaceutical.
Melanie
what is a bacterial
Eric Reply
Bacteria is a microscopic organism belonging to the kingdom prokaryotic
John
what is prokaryotic
Oliver
if you are here, read this free book, it is mostly correct, there are a few pictures that should be corrected
Lewis
thanks
Eric
A prokaryotes does not have lipid- bilayer bound organelles, they can reproduce by binary fission, they have a DNA region, most have a cell well, contains a plasmid, 70s ribosomes, high mutation rate due lack of certain DNA replication enzymes.
Eric
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Source:  OpenStax, Microbiology. OpenStax CNX. Nov 01, 2016 Download for free at http://cnx.org/content/col12087/1.4
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