Тема: Антибиотики (Antibiotics) Lesson’s Vocabulary:

Learn the following words and word combinations:

Antibiotics антибиотики

Compounds соединения

Derived производные

Accomplish выполнять

Effectiveness эффективность

Toxicity токсичность

Side-effects побочные эффекты

Route of administration способ введения

Cell клетка

Cell wall – стенка клетки

Cell contents содержимое клетки

Bacterial spectrum – бактериальный спектр

Interfering – отрицательно действующий

Fluoroquinolones – фторхинолоны

Lincosamides - линкозамиды

Macrolides - макролиды

Type of activity тип активности

Multiplying умножение

Fluoroquinolones фторхинолоны

Efficacy эффективность

Protein белок

DNA replication удвоение ДНК

Resistance устойчивость

Capable способный

Prophylaxis профилактика

Worsen ухудшать  

Read and the text and answer the questions:

Antibiotics

 Infections are very common and responsible for a large number diseases  adversely affecting human health. Most of the infectious diseases are caused by  bacteria. Infections caused by bacteria can be prevented, managed and treated  through anti-bacterial group of compounds known as antibiotics.

 Antibiotics can be loosely defined as the variety of substances derived from  bacterial sources (microorganisms) that control the growth of or kill other bacteria.  However, Synthetic antibiotics, usually chemically related to natural antibiotics,  have since been produced that accomplish comparable tasks.

Classifications

A common classifications for antibiotics are: -Bacterial spectrum: a) broad;  b) narrow.

-Route of administration: a) injectable;  b) oral.

-Type of activity: a) bactericidal;  b) bacteriostatic.

Antibiotics can also be classified based on their chemical structure. A similar level  of effectiveness, toxicity and side-effects is rendered by the antibiotics of same  structural group. Broad spectrum antibiotics are effective against a broad range of  microorganisms in comparison to narrow spectrum antibiotics. Bactericidal antibiotics kill the bacteria whereas bacteriostatic antibiotics halt the growth of  bacteria.

How Do Antibiotics Work?

 Various types of antibiotics work in either of the following two ways:

1.                  A Bactericidal antibiotic kills the bacteria generally by either interfering with the  formation of the bacterium's cell wall or its cell contents.  

Penicillin, daptomycin, fluoroquinolones, metronidazole, nitrofurantoin and cotrimoxazole are some example of Bactericidal antibiotics.

2.                  A Bacteriostatic antibiotic stops bacteria from multiplying by interfering with  bacterial protein production, DNA replication, or other aspects of bacterial cellular  metabolism.  

 Some Bacteriostatic antibiotics are tetracyclines, spectinomycin, trimethoprim,  chloramphenicol, macrolides and lincosamides.

Antibiotics are extremely important in medicine, but unfortunately bacteria are  capable of developing resistance to them. The problem of antibiotic resistance is  worsened when antibiotics are used to treat disorders in which they have no  efficacy (e.g. antibiotics are not effective against infections caused by viruses), and  when they are used widely as prophylaxis rather than treatment.

Answer the questions:

1.What compounds are known as antibiotics?

2.   What are common classifications of antibiotics?

3.   What are types of antibiotics work?

4.   What is the problem of antibiotics?