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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 ...


47

Salt water may have anti-septic properties due to the effect it has on water potential. Pure water has a water potential (Ψ) of zero. A concentrated salt solution has a lower (more-negative) water potential. The water potential of the salt solution is likely to be more negative than that of the pathogen's cytoplasm; the salt solution is therefore referred ...


40

This information is all strictly for Entonox - a brand of analgesic gas comprising 50% Oxygen (O2) and 50% Nitrous Oxide (N2O), Laughing Gas. This mixture is known as 'Gas and Air' and is in very common use. The active ingredient in Entonox is of course the nitrous oxide, so the discussion of the mechanism below refers solely to the N2O as you asked for. ...


34

There are different polio vaccines - one live (attenuated) vaccine which is given orally and one inactivated, which is injected. The main reason for using the live orally vaccine is that it provides excellent immunity (better than the inactivated) since it uses the natural infection route (oral-faecal) in the body where it enters through cells in the ...


23

No There are several reasons why this might not be true, as Alexander has discussed. An antibiotic often has a molecular target that isn't present in all bacteria, it's extremely hard to get antibiotics to certain parts of your body, and some bacteria will be defended against a antibiotic attack by biofilms, resistance mechanisms, and sheer statistical ...


22

There are several issues here: 1) Any mucous membrane is a specialized tissue for absorption. Mucous membranes are indeed not so good for passive diffusion, that makes them absolutely perfect tools for active absorption of certain substances, almost independently from the membrane type. To provide some examples: many drugs like cocaine are inhaled and ...


20

Short Answer: No. Background: First of all, there is no such thing as vitamin B17. The compound, amygdalin or laetrile, which is referred to by this term, is not a vitamin1. Amygdalin is indeed a cyanogenic glycoside (like glucosinolates, see this answer) which is poisonous to organisms including humans, because it forms cyanide which is toxic2. See this ...


18

Bacteria have a mesh-like structure surrounding their plasma membrane called a cell wall. The cell wall is made up of peptidoglycan polymers that form a rigid crystalline structure that helps protect the osmotic pressure of the bacterial cytoplasm. Penicillin and other β-lactams work by inhibiting the final step of peptidoglycan synthesis, which ...


17

Just a quick answer: No, there is no way to kill all bacteria in your body once they are there. The only way to keep a person sterile is to prevent any bacteria entering the guts during and all time after the birth. Look for gnotobiology and gnotobionts to learn more about these organisms (including humans). Here are some reasons why: Most antibiotics have ...


17

Perhaps the question may also be phrased, "Why is it common for plants to produce chemicals that possess pharmacological or toxicological effects in man and animals?", and to that question it is often reasoned that plants, being sessile and otherwise defenceless food sources for predators, produce compounds that affect the physiology of animals in such a way ...


16

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, ...


16

Nice question! I will directly begin with the process through which methamphetamine causes damage to neurons, putting in as much details as are known, and adding appropriate citations wherever required. Methamphetamine (METH) is known to act by increasing concentration of dopamine in brain1. When excess of dopamine is produced, it causes oxidative damage to ...


15

It would also be logical to note that a chewed tablet increases its surface-area-to-volume ratio for absorption relative to an intact tablet, for any absorptive tissue.


14

IDPs are indeed attractive drug targets and there are ongoing efforts to develop drug molecules that block interactions between a disordered and a structured protein. According to this relatively recent paper, however, these efforts have not brought a drug on the market, yet. A few promising studies have shown drug-like molecules that inhibit protein-...


14

The situation is definitely an extremely complex one, and you should probably forget about having an exact equation to define it. When talking about the effects of a substance on the organism there are several factors to take into account. These are generally put together under the term pharmacodynamics. Some of the factor to take into account are: The ...


14

The methodology behind homeopathy is scientific nonsense. If you dilute anything a billion times, it will have no chemical effect, not even if you shake it all the while. So no, homeopathy does nothing for cancer, or any medical condition at all. Of course plants can have active compounds in them, once scientists have identified those compounds, they can ...


14

Short version: This is nonsense, cancer does not arise from nutritional deficiencies. Long version: The substance is called Amygdalin, a poisonous cyanogenic glycoside. It can be found in higher concentration in the kernels of several plants including apricots, plums, bitter almonds, peach, plum. The semisynthetic, modified form is called Laetrile. Taking ...


12

It's worth noting that earlier this month a large body of resveratrol research was retracted: The University of Connecticut, in what clearly seems like an attempt to get ahead of damaging news, has announced an “extensive” investigation into research misconduct involving one of its scientists, Dipak K. Das. According to a press release, the ...


11

Isn't it illogical to give more of insulin for a deficit amount of receptors? Seems like there is some confusion in the definition of type-2 DM itself. According to the American Diabetes Association: If you have type 2 diabetes your body does not use insulin properly. This is called insulin resistance. At first, your pancreas makes extra insulin to make ...


10

I have been working on this problem for quite some time now and believe me getting specific binding is a real issue with IDRs. Also, since these regions dont form core structure of the protein, the residues are less conserved (more prone to mutations). So in case of evolving drug-resistance contributing proteins this become a bottleneck. I have done some ...


10

In a nutshell: in order to pass through the blood-brain barrier (BBB) the substance has to mimick soee properties of the substances that are allowed to pass through. There are different types of "transporters" -- integral proteins going through the cell membranes and accounting for the active transport of the substances they can actively bind to. Smaller ...


10

The WHO has their own methodology, the Anatomical Therapeutic Chemical (ATC, thank you commenter) classification system, for organizing such data (its impetus is comparing results between studies). Also, if you have $900 sitting around, you can get a subscription for the United States Pharmacopeia. I'm not sure if that can be spread across multiple ...


10

Paracetamol is a pain killer, it does not treat the cause of your illness, it only alleviates the symptoms. From its wikipedia page: Paracetamol [...], chemically named N-acetyl-p-aminophenol, is a widely used over-the-counter analgesic (pain reliever) and antipyretic (fever reducer). So, paracetamol does not make you better. Your immune system ...


10

Short answer The mechanism of action of serotonin-specific reuptake inhibitors, a commonly-prescribed class of antidepressants, is a downregulation of 5HT1A receptors through negative feedback. This downregulation of receptors takes time. Background Serotonin-specific reuptake inhibitors (SSRIs) are a class of antidepressants commonly prescribed to treat ...


10

I agree with @inf3rno: caffeine is a stimulant that acts on the brain and various other parts of the body (Snyder et al., 1981) and I wish to elaborate on its psychopharmacology. Caffeine's effects in the brain are mediated through adenosine A1 and A2 receptors (Daly et al., 1983). This results in a variety of actions (Fredholm et al., 1999). Most notably, ...


10

Aspirine irreversibly inhibits the enzyme cyclooxygenase. This enzyme facilitates the reaction from arachidonic acid to prostaglandin G2/H2. The further reaction leads to the generation of Thromboxane A2 which is important for the activation and aggregation of platelets. See the figure (from here) for an overview: Thromboxane A2 usually stimulates the ...


9

If you search clinicaltrials.gov (maintained by the NIH) for "resveratrol", you'll find 44 clinical trials, many of them ongoing or not yet started. A recent review by Smoliga JM et al states in the abstract: "Although the supporting research in laboratory models is quite substantial, only recently data has emerged to describe the effects of resveratrol ...


9

Risperidone prevents dopamine from acting on the pituitary gland by blocking dopamine type 2 receptors. One of dopamine's effects on the pituitary is to suppress prolactin production. In patients taking risperidone, prolactin production thus increases and prolactin levels in the body are higher than normal. In younger males, this can result in abnormal ...


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