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Fever is a trait observed in warm and cold-blooded vertebrates that has been conserved for hundreds of millions of years (Evans, 2015). Elevated body temperature stimulates the body's immune response against infectious viruses and bacteria. It also makes the body less favorable as a host for replicating viruses and bacteria, which are temperature sensitive ...


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Short Answer: Fever cannot cure Ebola simply because the virus is not temperature-sensitive. Background: Fever is a defense mechanism of the body which is specific to temperature-sensitive virus and bacteria. It is so because high temperature induces stronger immune response and makes the body hostile for the pathogen1. Ebola virus, on the other hand, is ...


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Most information here can be found broadly in Cellular and Molecular Immunology, 8th Ed. Here's how the flu vaccine works: Scientists forecast months in advance which strains they think stand to cause the most problems. The vaccine is often trivalent, protecting against three different strains on flu: Two influenza A and one influenza B. You can read about ...


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The goal of the vaccine is to provoke an immune response, therefore some degree of inflammation is expected in order for the vaccine to work. As swbarnes2 says, vaccines contain adjuvants, pro-inflammatory molecules that produces local inflammation and recruits immune cells to the site of the inoculation. Since you get the shot intramuscularily, ...


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Heated Honey and HMF In this paper, Studies on the physicochemical characteristics of heated honey, honey mixed with ghee and their food consumption pattern by rats, by Annapoorani, et.al.;International Quarterly Journal of Research in Ayurveda, 2010 Apr-Jun; 31(2): 141–146.doi: 10.4103/0974-8520.72363, the report finds a statistically significant increase ...


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In the US, infants are vaccinated against Hep B at birth and again a month or two later as well, because of the risk of maternal transmission. If the mother is known to be HepB positive, HBIG will also be administered. Perinatal HBV transmission can be prevented by identifying HBV-infected (i.e., hepatitis B surface antigen [HBsAg]-positive) pregnant ...


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Could you suggest a good source for beginners. - Louis Somers The interactions between the human body and its microbiome are quite complex. I am going to provide you with an answer that will be based on your comment that you would like an answer from a beginners perspective. For simplicity sake I will keep the answer to humans as the host organism, though ...


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The CD4 receptor is vital for the proper functioning of the immune system. It is found not only on T-Lymphocytes, but also on macrophages and dendritic cells. Its function on T-cells is to stabilize the interaction between the T-Cell receptor and the MHC Class 2 (often known as HLA II in humans) antigen complex on antigen presenting cells and improves the ...


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Article: How influenza virus infection might lead to gastrointestinal symptoms Source study: Respiratory influenza virus infection induces intestinal immune injury via microbiota-mediated Th17 cell-dependent inflammation. The idea is that Influenza virus infection originates in the respiratory tract. In response, the body produces these CCR9+CD4+ Th cells ...


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Fever normally under hypothalamic heat center's control which stays at limbic system of brain . Hypothalamus sets its own set point 36.4-37.2 in healthy peoples by some molecules named exogenous and endogenous pyrogens, especially PGE2 ,TNF and IL1. The most important mechanism for fever is directing blood flow from skin to deep vascular pools and ...


7

Since another posted answer addresses HepB vaccination at least as effectively as I would have, I'll say something about first-day scheduling for BCG, which is consistent with WHO guidelines (emphasis added): In countries with a high burden of TB, a single dose of BCG vaccine should be given to all infants as soon as possible after birth. Since ...


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This is an excellent question. You are on the right track with the random match idea. B-cells (as a group) develop receptors that bind every possible antigen and then get rid of the receptors that match antigens in our body. Some textbooks are a little more careful in their language, though, and say almost every possible antigen. See Alberts The ...


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Immunity can be a double edge sword. It is aimed to detect and destroy invading pathogens but it can also target the self, as exemplified in autoimmune diseases. To avoid this, many failsafe mechanisms exists. For example, imagine an innocuous foreign antigen gets into your body and reaches the lymph node. There it may find a naive B cell that has a ...


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Short Answer It should be noted that there are many non-pathogenic causes of sore throat, and I would suspect that you are not always distinguishing these causes from actual illness. In most cases, it would not be possible to build a response (immunological or otherwise) to avoid reacting to these stressors. Bacteria and viruses mutate frequently in ...


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All the body does is produce a ton of cells that can recognize single antigens. Each time you encounter pathogens, some of these naïve cells contact antigen that can activate them. The activated clone replicates itself, forming effector cells that can deal with pathogens. As the infection is cleared and the population of effector cells begins to contract (...


6

First: What your teacher says about the free floating antibodies is not correct. The first contact with a new antigen to generate specific immunity is done by naive B cells which have a membrane bound B cell receptor and their effector T cells. This contact can either happen directly or by the presentation of the antigen to the cell by antigen presenting ...


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Contrary to many beliefs our immune system needs no "training". It is permanently active and confronted with dozens to hundrets of antigens in our food, from dust we inhale and so on. This all happens to protect our body from the environment and the immune system is pretty efficient with that and certainly it is not getting lazy. By vaccinating against a ...


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We don't know. More precisely, we know of many, many different reasons why the immune system deteriorates with age, but we don't really know which are different measures of the same thing, which are independent factors, which factors actually cause problems and which are harmless and incidental, and so on. There are too many age-related phenomena to ...


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Short answer Aquagenic urticaria is though to be caused by dissolved allergens in water and not by water per se. background Aquagenic urticaria is a rare condition in which urticaria (hives) develop rapidly after the skin comes in contact with water, regardless of its temperature. Water allergy in itself is obviously a ridicule, as up to 60% of the human ...


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Molecular context is important here. E.coli in your colon is OK with the body, it is taken up by phagocytes as part of normal "surveillance". Your immune system will learn and gain "tolerence" to these mutualistic bacteria as long as they are in the correct environment. If that same E.coli is a pathogenic strain or finds a way into the blood stream (sepsis),...


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'Pore' is a confusing term. Sweat is produced in sweat glands, and subsequently excreted through a duct, as indicated in the image below (sudoriferous ~). In short, viruses cannot enter the body through these glands because the glands don't really open up into the body, but instead the inside of the sweat gland is lined with sweat-producing cells (fig 2 and ...


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In one small study, rhinovirus in the immunocompromised led to significant mortality from lower respiratory infection: Among high-risk patients with cancer, rhinovirus infections are often fatal. In a study of 22 immunocompromised blood and marrow transplant recipients who were hospitalized with rhinovirus infections, 7 (32%) developed fatal pneumonia. ...


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The immune system is capable of recognizing pathogenic ("bad") bacteria, either by components of the innate (non-specific) or adaptive (specific) immune system. Pathogenic bacteria will have antigen on their surface that mark them as 'foreign', leading to an immune response targeted to the bacteria. In contrast, the immune system tolerates the normal flora ...


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The Native Americans and smallpox First I want to note that some of the posted answers are not quite accurate. For example, smallpox ravaged the Native American population because they did not have high-affinity MHC molecules for it, which is an evolved trait. MHC molecules must be capable of binding to a large class of peptides, at least weakly, to allow ...


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The Body Story. --Have to add some characters for the system to be happy--


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Naive T cells are regularly matured in the thymus where they're released into the blood. A majority are CD4+, but many are also CD8+. As a caveat, many are TCRαß+, and few are TCRyδ+ (outside the scope here but fun to look up and read). From there, they home to the lymph node where they hang in the T cell zone until blood trafficking signals coax them into ...


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The short answer seems to be that fevers help combat microbes (a term I take herein to include viruses for brevity), which aren't a part of the threat addressed in an allergic reaction. While there's not a full consensus on which benefits, if any, a fever brings to the response to microbes, both humans and other warm-blooded vertebrates fare better with ...


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While you’re correct that NK cells are often activated (in part) by the absence of MHC-I, they require other signaling events to become fully activated: The Molecular Mechanism of Natural Killer Cells Function and Its Importance in Cancer Immunotherapy. Paul & Lal. Frontiers in Immunology. 2017. Activating Receptors on NK Cells Lack of MHC ...


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This answer focuses primarily on allergies, for which there is more reliable research, but touches on general immunity towards the end. It is certainly true that the prevalence of allergies is increasing worldwide, and seems to be related to a rise in the so-called 'modern lifestyle' which avoids exposure to potentially harmful environmental factors. The ...


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Here's a short and simplified explanation. The antibodies that arise in a flu infection are more "intended" to prevent future infections than to clear the present infection. Infections drive T cell responses as well as antibody responses, and the T cells appear a little earlier (peaking at maybe a week) and are probably very useful for clearing the present ...


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