56

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 ...


43

Short answer A bittering agent may be applied to therapeuticals to prevent pediatric poisonings, but many drugs inherently taste bitter by themselves. Background Bitter taste is thought to have evolved as a way to decrease the risk of ingesting toxic substances, which may explain why many drugs taste bitter. In other words, classes of compounds that may harm ...


35

There are multiple biological mechanisms that can be brought to bear for distinguishing between atoms. In addition to binding properties (e.g., ionic charge, electronegativity, bond strength), there is also the size of the atoms and even their vibrational properties. For one of these mechanisms to actually be used, however, it needs to be evolutionarily ...


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 ...


21

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 ...


19

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

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 ...


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

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 ...


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 ...


13

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 ...


12

"Irrational" design in these papers refers to combinatorial mutagenesis, which is put forward as the alternative to "rational" protein design. Rational design involves using existing information about a protein to choose residues to mutate. From Nixon et al.: Alteration of function by rational approaches can be achieved through single-point ...


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

Does one wing of fly contain harmful microbes and the other contain only antibodies? False. A healthy microdose of skepticism is all you would ever need here. It's just a silly attempt to prove a literal interpretation of a religious text with minimal effort. Unfortunately, the paper looks, reads, and smells like a joke. Ignoring its nonsensical title and ...


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 ...


9

Short answer Various inhalants, most notably organic solvents including those used in paint and glue suppress appetite. Background From the Division of Alcohol and Drug Abuse I learned the following: Initial effects [of various inhalants] include nausea [...], and a loss of appetite. And the Humanitarian Irin News reports the following on Nepali ...


9

This is true for the beginning of the disease. As a reaction to the reduced sensitivity of the cells in the body to insulin (and thus less uptake of glucose from the blood and a resulting hyperglycemia) the body produces more and more insulin to cope with this problem. At some point the insulin producing beta cells cannot increase the production anymore and ...


8

Firstly, most plants or other natural medicinals existed way before we knew about them; it's not that plants mimic drugs, its that drugs mimic plants. To answer your question succinctly, compounds that we can use for our own medical benefit often do other things, we just adapt them for our own purposes. Penicillin is probably the best example. It didn't ...


8

Short answer The causes of death after heroin, cocain or cannabis overdose are mainly due to cardiac and respiratory arrest, and not to neurotoxic effects. Background The cause of death after a lethal overdose of your mentioned drugs are the following : Cocaine (lethal dose: 30 mg - 5 g via mucus membrane (EMCDDA)): Cocaine-related deaths are often a ...


8

The issue is complicated. In general it depends on the specific spinal reflex and on the specific anaesthetic. But it seems that the modern general anaesthetics usually do NOT block monosynaptic spinal reflexes (such as knee-jerk). Here are two figures from Baars et al. 2009 that show that propofol and sevoflurane strongly inhibit withdrawal reflex (spinal ...


8

Opiate pain killers or pain killers that act on opioid receptors have a different mechanism of action than NSAIDs. They tend to act as receptor agonists which exert their effect on the CNS (oxycodone as an example). Opioid receptors are associated with analgesia, CNS depression, sedation, etc. Tylenol on the other hand is thought to exert its effect by ...


7

A mechanistic study aims to uncover a mechanism. It can be a mechanism of the disease (exactly how does the disease do damage to the body), or a mechanism of a drug (exactly how does the drug prevent or repair the damage) that is being investigated. Understanding mechanism, be it mechanism of disease or mechanism of the drug, is very important toward ...


7

Yes, there are a few. Mostly they are designed in combination with X-ray crystallography of the target which should be inhibited. Then molecules are designed which fit specifically into these targets. The oldest example I could find is Dorzolamide which acts as a carbonic anhydrase inhibitor. See here: "Application of the three-dimensional structures of ...


7

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

the first time you take them you will feel better, think sharper, and act better You are probably thinking of amphetamines, not opiates. Militaries have used amphetamines for just that purpose for decades, particularly for situations where long periods of attention are necessary. The problems are addiction, adaptation (lessening effects over time), ...


7

Fluorine has a combination of unique chemical properties, which makes it very useful in drug design : It is small, such that replacing a C-H with a C-F is often possible, from a sterical point of view. Halogens, which share some of the other desirable properties of fluorine, are much larger. It is very electronegative: it will attract electrons strongly, ...


7

Receptors Any drug or compound with specific effects has a receptor. You can read about this general concept in Goodman and Gillman's The Pharmacological Basis of Therapeutics. Chapter 1 introduces the concept, chapters 3 and 5 expand further. As far as the history of this concept is concerned, receptors mediating the specificity of action was first clearly ...


7

Aciclovir specifically targets HSV-family viruses. It is metabolized by a viral-specific enzyme into an inhibitor of the specific DNA polymerase expressed by the virus: in infected cells, HSV or VZV coded thymidine kinase facilitates the conversion of aciclovir to aciclovir monophosphate, which is then converted to aciclovir triphosphate by cellular ...


7

I've heard this rumor for years, both from pro- and anti-drug people, and it is not true. According to this review of LSD's pharmacology, its half-life in the body is about 5 hours, with it being completely cleared within about 15-28 hours. There is no evidence that it accumulates long-term in fat, cerebrospinal fluid (CSF), or anywhere else in any ...


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