“MEDICAL ENGLISH ”

TEACHER:

Dra. Rosa Gonzales Llontop

STUDENTS:

Failoc Rojas Virgilio Fuentes Muro Oscar Gonzales Yovera Jhean Mas Golac Ciro Plasencia Dueñas

Esteban Alberto Sajami Puertas Jhonatan

INTRODUCTION

The Biochemistry is a science that studies the chemistry of living organisms, especially proteins, carbohydrates, lipids and nucleic acids, and other small molecules in cells and also the chemical reactions that these compounds (metabolism) allowing perform to obtain energy (catabolism) and generate biomolecules (anabolism).

The Pharmacology is a branch of the Biochemistry; this science studies the drug action. More specifically, it is the study of the interactions that occur between a living organism and chemicals that affect normal or abnormal biochemical function.

Actually the pharmacology has a great impact in medicine as in biochemistry, because the different types of drugs produce different effects in the same person, according with many factors as for example: the wheater and the emotional aspect.

BIOCHEMISTRY OF DRUG ABOSORCIÓN

DRUG TRANSPORT ACROSS CELL MEMBRANES:

Any movement of a drug molecule within the body requires passage through biological

membranes. This affects both the absorption mechanisms as in the distribution or elimination.

There are two mechanisms:

(A) through intercellular clefts: Filtration

(B) through cell membranes

Filtration depends on:

1) Molecular weight of the drug: the more Pm, more difficult to pass.

2) Concentration gradient: the drug passes from where there is more concentration where there

is less.

3) Distance between cells.

4) Pressure on either side of the wall: hydrostatic pressure, which makes the drug between, and

osmotic pressure, which causes him to stay.

The transport across cell membranes depends on:

Pm of the drug.

Concentration gradient.

Liposolubility

Degree of ionization

DISTRIBUTION OF A MEDICAMENT

The distribution is the transport of the medicament for the blood up to the place where he exercises his action. In the blood the molecules of medicament can go of three forms:

- Dissolved in the plasma.

- Inside certain cells.

- Joined plasmatic proteins: the interaction with plasmatic proteins is very frequent, though it is variable according to the medicaments. With much it is the albumen the protein that has major capacity of fixation. The union with the protein is realized generally by ionic bonds, though also covalent bonds exist, such as the forces of Walls Goes der. It is a chemical union that follows the law of action of masses: Medicament (F) + Protein (P) FP

DISPOSAL OF A DRUG

The excretion study ways to remove a drug and its active and inactive metabolites from the body to the outside.

Routes of excretion: they all contribute physiologically to expel the liquid and organic substances.

The drugs are excreted in the following ways: mainly by the kidney after biliary-enteric by.

The kidney: it is the most important route of excretion of drugs. Its importance in pharmacology decreases when a drug is metabolized in its entirety, and only eliminated by the kidney inactive metabolites.

Filtration and secretion are the duties of the kidney that help, not surprisingly, an increase in the amount of drug in the urine and the reabsorption opposite.Both secretion and reabsorption by active transport occur or by passive diffusion.

Biliary excretion: the drug is metabolized in the liver, biliary system passes, then the intestine and out through the feces. Sometimes part of the drug that goes by the gut and goes back to be reabsorbed back due to the movement leading to enterohepatic circulation (drug out through the bile, reabsorbed in the intestine through the portal system and again the liver, causing a vicious circle)

Pulmonary excretion: some drugs are excreted in the breath, such as alcohol and general anesthetics.

MECHANISMS OF ACTION ANTIBIOTICS

Some antibiotics work by inhibiting bacterial cell wall synthesis by interrupting the process at different stages and union transpeptidation of the peptidoglycan cell wall that are, eg penicillins, cephalosporins.

Agents that act by inhibiting the functions of the membrane permeability alter the bacterial cell membrane, eg the polymyxin, the polyenes.  The antimicrobials may inhibit bacterial protein synthesis reversiblede usually in the form of the following ways:- For the selective inhibition of DNA synthesis or replication of bacteria (nadilíxico acid, griseofulvin, metronidazole, etc.).- By inhibiting RNA polymerase, affecting nucleic acid metabolism and preventing the synthesis of all forms of bacterial RNA, eg rifampicin.According to the site of the antimicrobial action of these include:Inhibitors of folate synthesis eg sulfonamides.Inhibitors of cell wall synthesis example, lactams.Inhibitors of RNA polymerase enzyme eg Rifampicin.Cell membrane inhibitors eg ketoconazole.Protein synthesis inhibitors eg aminoglycosides, tetracyclines.

Inhibition of bacterial metabolism

MECHANISMS OF ACTION VIRICO

Virused are composed of genetic material and, sometimes, some enzymes, enveloped by a capsule made of protein, and rarely covered by a lipid layer. Viruses can not reproduce themselves and spread kidnapping cells to do the job for them.

To develop the first antiviral, researchers cultured cell populations and infected with the virus target. Then chemicals are introduced, and which seemed to have an effect, were selected for further study.

This test procedure was time consuming and error, in the absence of good knowledge of how the virus target is not very effective for the discovery of antivirals that have few side effects. It was not until the 1980's, when they began to be described the complete genetic sequences of viruses, the researchers began to learn its operation in detail exactly what kind of molecules are needed to attack the structure of the virus.

Bibliography

http://www.ucl.ac.uk/Pharmacology/what-is-pharmacology/what.htm

http://www.medscape.org/viewarticle/421137_1

Cathedra of scientist Medicals "Manuel Fajardo" [Side Web] Mechanisms of action [Available] http://www.uvfajardo.sld.cu/Members/Eneida/plonearticlemultipage.2007-07-19.0062603604/mecanismos-de-accion