Questions tagged [pathogenesis]
Pathogenesis is the mechanism by which a disease is causing the disease. For bacteria this can be the secretion of a toxin which is toxic for the host.
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Can human pathogens present on plants become plant pathogens?
Since human pathogens sometimes live on the surface of plant leaves(read here and and here), and there are plant-pathogen microbes also living on leaf surfaces, is it possible for plant virulence ...
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Can the innate immune system defeat a pathogen by itself? Fast enough that we don't develop antibodies, etc.?
Would we have any way of knowing if our innate immune system destroyed a pathogen without involving the adaptive?
Could a symptomless person who tests positive for COVID-19 with the RNA test, e.g., ...
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From a hosts point of view, which comes first, effect of toxins on pathways or identification of toxins by immune system?
From a pure biology perspective, when a pathogen (gram-negative bacteria) affects a host by secreting toxins, what comes first, the effect of the toxin on the pathways or identification of the toxin ...
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Neisseria meningitidis transformation into a pathogen
I read the wikipedia article about Neisseria meningitidis, and it says that
N. meningitidis is a part of the normal nonpathogenic flora in the nasopharynx of up to 5–15% of adults
In some cases ...
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How could be the concentration of airborne pathogens in a specific indoor space be measured?
I wonder if it is possible to measure the concentration of airborne pathogens in a specific indoor space in order to extract a percentage value. This value would be helpful to determine specific ...
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Why are human feces riskier than urine with regard to spreading diseases?
I came across a Wikipedia article titled "Urine diversion". It explains different ways, including using special diversionary toilets, and treating the collection of human feces and urine ...
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Can a pathogen be totally resistant to the human immune system?
Can a pathogenic organism be totally resistant to the human immune system? For the purpose of this question, the organism in question must cause a disease.
Examples of organisms that would qualify as ...
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Are there any non-pathogenic gram-positive bacteria in human gut?
I wish to know if there are any non-pathogenic (not even opportunistic pathogen) gram-positive bacteria in the human gut? Is there any reference that shows there exists a non-pathogenic gram-positive ...
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What is the difference between transport proteins and effector proteins in gram-negative bacteria?
When considering pathogenic gram-negative bacteria, is there any difference between the function of transport proteins and effector proteins? Or are they of the same functionality? Any reference ...
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Is there any non-pathogenic gram negative bacteria?
In the category of Gram-negative bacteria, is there any non-pathogenic species? Is such a list of non-pathogenic gram-negative bacteria's available? Can you give maximum 5 examples of such bacteria ...
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Do non-pathogenic organism not have PAMPs? Are there any research paper which proves that a certain microbe is non-pathogenic?
According to this
PAMPs are delivered along with additional information that can be
used by the host to distinguish pathogenic from nonpathogenic
microbes and thereby guide the ensuing innate ...
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How can a pathogenic bacterium be avirulent?
Streptococcus pneumoniae R6 is a pathogenic bacterial strain but it is avirulent. How can a pathogen be avirulent. What does it mean if a pathogenic bacterium is avirulent?
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What is the step by step procedure that leads the T cell to release chemokines?
When T cell receptors bind to the receptor of an antigen presenting cell, is this what leads to the release of chemokines? I know that T cell release of chemokines leads to the migration of other T ...
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How is TB harmful in HIV patients?
The mycobacterium of TB doesn't secrete any toxins. The cause of disease in the immunocompetent is the collateral damage due to the immune response against disseminated infection. But then, when HIV ...
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What decides whether an ulcer/chancre is painful or painless?
In sexually transmitted infections, it is important to differentiate a painful ulcer from a painless one. This is because painless ulcers are seen in the chancre of primary syphilis while painful ...
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Do all tumors form the same way? [closed]
Do all tumors - both benign and malignant - form when proto-oncogenes and/or tumor suppressor genes experience mutations? Were all malignant tumors once benign?
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Availability of a database containing the proteins of Vibrio cholerae and their corresponding gene sequences
I wanted a list of all the proteins (amino acid sequences) and their corresponding gene sequences of Vibrio cholerae. I tried to search in patric, but the number of amino acid sequences and gene ...
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Quantity of toxin release by pathogen in host
I came across these lines from this paper:
Pathogenic microbes exert a broader sphere of influence by releasing a bolus of toxin that can act upon many cells within a given tissue and/or diffuse ...
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Why are sarcomas rare compared to carcinomas?
A sarcoma (from the Greek σάρξ sarx meaning "flesh") is a cancer that
arises from transformed cells of mesenchymal origin. Thus, malignant
tumors made of cancellous bone, cartilage, fat, muscle, ...
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Are there specific non-protein substances that pathogens release into their host?
Reading research articles, I have found out that proteins called effectors get released into the host cell when a pathogen attacks a host. My question is, whether pathogens also release non-protein ...
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Does a specific blood group enhance the Plasmodium growth?
I am maintaining Plasmodium falciparum cultures for past 6 months. For the blood culture, usually we lab members take turns and donate blood for the culture. I observed that the parasite's normal ...
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The effects of auto-brewery syndrome
Why are some people affected so differently by auto-brewery syndrome differently if the syndrome seems to be caused by the single organism saccharomyces cerevisiae? It is known that the syndrome has ...
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Why does histamine release in Type I hypersensitivity help in case of parasites?
The IgE system exists because the same events which lead to often-life threatening complications of allergy, in presence of parasites are helpful in their elimination.
The tissue injury mediated ...
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Pathogenesis of type IV hypersensitivity
In hypersensitivity, as I understand it, a normal immune response gets excessive, misdirected or wrongly regulated to cause tissue injury. The various types determine the various ways in which the ...
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relationship between cytokines
This is for a mathematical research. I am building a model to identify severe dengue patients through the interaction of cytokines S1P,IL1b,TNFa,PAF and IL10.
For this I would like to know if there ...
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What is a functional screen?
I was going through this paper, but did not understand a term.
What is the meaning of functional screen?
(I am not a biology student, I don't understand much, and a small simple explanation would ...
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Secretion in Gram negative bacteria
Among the 6 secretion systems in bacteria, can these 6 ways be sorted out in the order of how harmful it is to the human host? Like say type 3 is highly virulent so that comes first, but I don't know ...
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Difference between modules in KEGG Module
The KEGG module M00115 includes a set of reactions while M00542 does not have any; it just shows the list of enzymes. Is the reaction set for M00542 still unknown?
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Regulation of V. cholerae virulence factors
So I know that several different environmental signals, such as pH, bile, and temperature, regulate virulence gene expression in V. cholerae. Specifically, they control expression of the genes ...
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Why is knowledge of bacterial pathogenesis important? [closed]
Why is knowledge of pathogenesis increased more and more for common bacterial pathogens? Most of these studies lack a near application in disease control such as vaccines or antibiotics.
Examples:
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Do distinctions between dry, tickly and chesty coughs have any medical basis?
Background
At least in Britain you normally come across distinct kinds of cough medicine "chesty", "dry" and "tickly".
Questions
Are "chesty", "dry" and "tickly" coughs always due to microoganisms?
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What is the name of systemic tension of muscles?
I meat a overtrained friend (25 years old) who cannot rest.
He has all muscles and most of the skin very tense.
He is practising regularly in gym and sleep badly.
He moves like a stick figure and has ...
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Can inhibition of lymphocytes migration be a direct cause of chronic inflammation?
Here is the original slide:
I am thinking about the "cord factor" sentence in a more general case.
Assume you inhibit Leucocytes migration.
How does this lead to accumulation of macrophages in the ...
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Fibrinous inflammation, exudate and scarring in monotonous movements and ageing
I have palpated many hard organs during my work and studies.
I have seen many young and old people who have hard organs, like very hard shoulder - very common.
I have interviewed some of them, some ...
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What is the difference between fibrogenesis and fibrosis?
Fibrosis is the formation of excess fibrous connective tissue in an organ or tissue in a reparative or reactive process.
I used the word "fibrogenesis" as the outcome of acute inflammation (healing).
...
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Can pulmonary infarction be asymptomatic?
I think it can because there are many parts in lungs.
Like for some COPD patients.
However, I am not sure if COPD patients can have infarction.
Lungs have parallel circulation.
Red infarct is ...
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Pathogenesis of Chronic Venous Congestion in Lungs?
I am thinking how CVC in lungs lead to the left-sided heart failure.
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What is the pathogenuc mechanism of brown pigment lipofuscin in muscle atrophy?
I think it is autophagy. Lysosomal degradation. Autophagocytosis.
Example of the brown pigment (lipofuscin) here:
I am not sure if autophagy is the right answer to the "pathogenic" mechanism of ...
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Pathogenesis of chronic venous congestion in skin?
I think CVC cannot lead to heart failure primarily.
So let's think its pathogenesis in skin now only.
I think the pathogenesis is like this
dilation of veins and capillaries due to impaired venous ...
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Can systemic intravascular thrombosis cause brain infarction?
I wonder if the thrombus can pass through the brain-blood barrier because I think small molecules like O2, CO2 and ethanol can pass it.
Probably, in some diseases where the permeability of the barrier ...
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What are these white areas of coronary thrombosis?
Please, see the picture where the areas (1,2,3) look little yellow:
I think these areas are fat, platelets and/or air.
I think 3 is fat/platelets while 1 is air/platelets.
There also exists white ...
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Are there any forms of heart failure where cell size decreases?
I think hypertrophy happens in most of the cases. However, I am not sure if hypertrophy always happens. I started to think about wet lungs (pulmonary reason for the left-sided heart failure).
Can the ...
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Can systemic venous congestion caused by tumor?
I am thinking, if 1) little compressed superior caval vena and 2) some vein compression by tumor, can cause systemic venous congestion.
I think this is only in rare occasions.
However, the question ...
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What can thrombosis lead to?
I am thinking this question.
Thrombosis can result in
organisation of thrombus,
sepsis
thromboembolism,
fibrinoid swelling
adiposity.
I fibrinoid swelling (edema) (4) can occur.
Also, I think (3) ...
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Why do 6-8% of diphtheria patients do not develop natural immunity after being affected?
I am thinking of why some patients do not have natural immunity after exposure to the A-B toxin of diphthria.
I think the A-B exotoxin is the key factor causing this disease and should trigger memory ...
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How host defends against S. pneumoniae capsule?
The host response involves at least phagocytosis and probably localised acute inflammatory response at least after the colonisation.
I am thinking how the host can defend against pneumolysin which ...
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What does this sentence about toxemia and Clostridium tetani mean?
I know that Cl tetani is not invasive and strictly localised.
I think toxemia means spread in the blood.
I am thinking this sentence
The volume of infected tissue is small, and the disease is ...
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Pathogenesis of Group B Streptococci and C5a
I am thinking the pathogenesis of the C5a in GBS.
I think the pathogenesis happens like
C5a-peptidase in acid environment (Sialic acid, capsule) $\to$ cleaves C'-derived Neu chemoattractant C5a $\...
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