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FEVER The hypothalamus is the organ responsible for temperature regulation. It contains...

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FEVER The hypothalamus is the organ responsible for temperature regulation. It contains thermosensitive neurons to control thermoregulatory functions in response to information collected by temperature sensors. [4] For example, when pyrogens enter the body, they raise the hypothalamic set-point. Other factors also act to shift temperature.
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FEVERThe hypothalamus is the organ responsible for temperature regulation. It contains thermosensitive neurons to control thermoregulatory functions in response to information collected by temperature sensors.[4] For example, when pyrogens enter the body, they raise the hypothalamic set-point. Other factors also act to shift temperature.

Shivering generates heat while peripheral vasoconstriction prevents dermatological heat loss and conserves heat .Fever serves a function for the organism by enhancing neutrophil migration, increasing neutrophilic production of antibacterial substances, increasing interferon production, upregulating antiviral and antitumor activity, and increasing growth of T-cells

Usefulness of fever

Theoretically, fever has been conserved during evolution because of its advantage for host defense.There are certainly some important immunological reactions that are sped up by temperature, and some pathogens with strict temperature preferences could be hindered.The overall conclusion seems to be that both aggressive treatment of fever.and too little fever control.can be detrimental. This depends on the clinical situation, so careful assessment is needed.

Fevers may be useful to some extent since they allow the body to reach high temperatures. This causes an unbearable environment for some pathogens. White blood cells also rapidly proliferate due to the suitable environment and can also help fight off the harmful pathogens and microbes that invaded the body.

Prostaglandins

Prostaglandins were first discovered and isolated from human semen in the 1930s by Ulf von Euler of Sweden. Thinking they had come from the prostate gland, he named them prostaglandins. It has since been determined that they exist and are synthesized in virtually every cell of the body.

Functions of Prostaglandins

Activation of the inflammatory response, production of pain, and fever. When tissues are damaged, white blood cells flood to the site to try to minimize tissue destruction. Prostaglandins are produced as a result.

Blood clots form when a blood vessel is damaged. A type of prostaglandin called thromboxane stimulates constriction and clotting of platelets. Conversely, PGI2, is produced to have the opposite effect on the walls of blood vessels where clots should not be forming

Certain prostaglandins are involved with the induction of labor and other reproductive processes. PGE2 causes uterine contractions and has been used to induce labor.

Certain prostaglandins are involved with the induction of labor and other reproductive processes. PGE2 causes uterine contractions and has been used to induce labor.

Prostaglandins are involved in several other organs such as the gastrointestinal tract (inhibit acid synthesis and increase secretion of protective mucus), increase blood flow in kidneys, and leukotriens promote constriction of bronchi associated with asthma

Treatment

Fever should not necessarily be treated. Fever is an important signal that there's something wrong in the body, and it can be used for follow-up. Moreover, not all fevers are of infectious origin.

Even when treatment is not indicated, however, febrile patients are generally advised to keep themselves adequately hydrated, as the dehydration produced by a mild fever can be more dangerous than the fever itself.

Water is generally used for this purpose, but there is always a small risk of hyponatremia if the patient drinks too much water. For this reason, some patients drink sports drinks or products designed specifically for this purpose.

Treatment of fever should be based primarily on lowering the set-point, but facilitating heat loss may also contribute. The former is accomplished with antipyretics. Wet cloth or pads are also used for treatment, and applied to the forehead.

Heat loss may be an effect of (possibly a combination of) heat conduction, convection, radiation, or evaporation (sweating, perspiration). This may be particularly important in babies, where drugs should be avoided. However, if water that is too cold is used, it induces vasoconstriction and prevents adequate heat loss.

NSAIDs

Prostaglandins are a related family of chemicals that are produced by the cells of the body and have several important functions. They promote inflammation, pain, and fever, support the function of platelets that are necessary for the clotting of blood, and protect the lining of the stomach from the damaging effects of acid

Prostaglandins are produced within the body's cells by the enzyme cyclooxygenase (Cox). There actually are two Cox enzymes, Cox-1 and Cox-2. Both enzymes produce prostaglandins that promote inflammation, pain, and fever. However, only Cox-1 produces prostaglandins that support platelets and protect the stomach. Nonsteroidal anti-inflammatory drugs (NSAIDs) block the Cox enzymes and reduce prostaglandins throughout the body

As a consequence, ongoing inflammation, pain, and fever are reduced. Since the prostaglandins that protect the stomach and support the platelets and blood clotting also are reduced, NSAIDs can cause ulcers in the stomach and promote bleeding. NSAIDs differ in how strongly they inhibit Cox-1 and, therefore, in their tendency to cause ulcers and promote bleeding.

Effects of Aspirin and other Pain Killers:

When you see that prostaglandins induce inflammation, pain, and fever, what comes to mind but aspirin. Aspirin blocks an enzyme called cyclooxygenase, COX-1 and COX-2, which is involved with the ring closure and addition of oxygen to arachidonic acid converting to prostaglandins. The acetyl group on aspirin is hydrolzed and then bonded to the alcohol group of serine as an ester. This has the effect of blocking the channel in the enzyme and arachidonic can not enter the active site of the enzyme.

By inhibiting or blocking this enzyme, the synthesis of prostaglandins is blocked, which in turn relives some of the effects of pain and fever.

What are the side effects of NSAIDs?

NSAIDs are associated with a number of side effects. The frequency of side effects varies between the drugs. The most common side effects are nausea, vomiting, diarrhea, constipation, decreased appetite, rash, dizziness, headache, and drowsiness.

NSAIDs may also cause fluid retention, leading to edema. The most serious side effects are kidney failure, liver failure, ulcers and prolonged bleeding after an injury or surgery. Some individuals are allergic to NSAIDs and may develop shortness of breath when an NSAID is administered.


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