why is the drug actinomycin used only on research applications or in the treatment of cancer? answer because it is active against both prokaryotic and eukaryotic cells
Full Answer
Why is actinomycin not used for chemotherapy?
Why is the drug actinomycin only used in research applications or in the treatment of cancer? because it is a very expensive drug because it is active against both prokaryotic and eukaryotic cells because it cannot be given orally, making it difficult to administer to patients because it causes severe allergic reactions in most patients
What is actinomycin D used for?
Why is the drug actinomycin used only in research applications or in the treatment of cancer? because it is active against both prokaryotic and eukaryotic cells The first true antibiotic was __________, which was discovered by __________.
Which Actinomycin is associated with SOS?
Although actinomycin is the first anticancer antibiotics, because of its severe toxicity, it was not used long in cancer chemotherapy; related molecules and analogues were subsequently discovered, and are now widely used for cancer chemotherapy.
Is actinomycin D the same as Cosmegen?
Although it differs from most intercalating drugs in that it lacks a positive charge, it has been suggested that this is compensated by its high dipole moment, arising from a non-symmetrical distribution of polar substituents. 15 Dactinomycin is used to treat sarcomas, pediatric solid tumors (e.g. Wilms' tumor, a type of renal tumor), germ cell cancers (testicular cancer), and …
Which of the following is a primary advantage of semisynthetic drugs?
Which of the following is a primary advantage of semisynthetic drugs? They are less stable and consequently have fewer side effects. They are more effective than the unmodified natural antibiotics.
How does mupirocin interfere with protein synthesis in Gram positive bacteria such as staphylococcus and streptococcus?
Mupirocin inhibits bacterial RNA and protein synthesis by binding to bacterial isoleucyl tRNA synthetase, which catalyzes the formation of isoleucyl tRNA from isoleucine and tRNA. This prevents incorporation of isoleucine into protein chains, leading to arrest of protein synthesis.
What is meant by selective toxicity?
Selective toxicity refers to: Antimicrobials that are toxic to both human and microbial cells. Antimicrobials that are toxic to neither human or microbial cells. Antimicrobials that are more toxic to human than microbial cells. Antimicrobials that are more toxic to microbial than human cells.
Which of the following need to be considered when selecting an antimicrobial?
The use of antibiotics requires a consideration of three elements: the antibiotic, the organism, and the patient. The antimicrobial susceptibility of a micro- organism can be determined easily.
What is mupirocin effective against?
Mupirocin apparently exerts its antimicrobial activity by reversibly inhibiting isoleucyl-transfer RNA, thereby inhibiting bacterial protein and RNA synthesis. Mupirocin has excellent in vitro activity against staphylococci and most streptococci but less activity against other gram-positive and gram-negative bacteria.
Why is mupirocin ointment used?
Descriptions. Mupirocin topical cream is used to treat secondarily infected traumatic skin lesions due to specific bacteria. Mupirocin topical ointment is used to treat impetigo. This medicine works by killing bacteria or preventing their growth.Feb 1, 2022
Why is the drug actinomycin?
Actinomycin D is a well-known antibiotic that exhibits high antibacterial and antitumor activity. It has been widely used in clinical practice since 1954 as an anticancer drug to treat many tumors, such as Wilms and Ewing tumors, testicular cancer, sarcomas, and choriocarcinoma.
Why selective toxicity is an important feature of antibiotics?
Antibiotics must have Selective Toxicity for the Microbe The reason for this is that only compounds with selective toxicity can be used clinically. The selective toxicity of antibiotics means that they must be highly effective against the microbe but have minimal or no toxicity to humans.
Why is selective toxicity important?
The selective toxicity is of great significance in the field of agriculture, and human and veterinary medicines. For instance, in agriculture different forms of life (e.g. weeds, insects, fungi, etc.) damage our crops as weeds, pests or pathogens and finally affect the agricultural production.Apr 6, 2020
Which of the following are the three factors that should be known before selecting an antimicrobial?
The WG agreed on the following basic criteria for the selection of antimicrobial agents: 1) the agent should be useful when screening various resistant bacteria, 2) the agent should serve as a useful guide for physicians and residents when selecting antimicrobial agents, and 3) the agent should be useful for ...
For which of the following reasons would antimicrobial susceptibility testing be performed?
You may need this test if you have an infection that has been shown to have antibiotic resistance or is otherwise hard to treat. These include tuberculosis, MRSA, and C. diff. You may also need this test if you have a bacterial or fungal infection that is not responding to standard treatments.Mar 9, 2021
What is the most effective antimicrobial?
Sterilizers are the strongest type of public health antimicrobial product. In addition to bacteria, algae, and fungi, they also control hard-to-kill spores. Many sterilizers are restricted-use pesticides.
What drugs block viral entry into cells?
Medications which block viral entry into cells include (adhesin/analog/attachment) antagonists. attachment. Some bacteria develop resistance to groups of drugs because the drugs are all structurally similar to each other; this is a phenomenon known as (cross/multiple/synergistic) resistance. cross.
What is the antimicrobial polymyxin?
the antimicrobial polymyxin. disrupts cytoplasmic membranes. External infections can be treated by (intramuscular/surface/topical) administration, in which a drug is applied directly to the site of infection. topical. There are relatively few antifungal medications available compared to antibacterial drugs. (T/F) true.
What is the mechanism of action of vancomycin?
The mechanism of action of the antibiotic vancomycin is. inhibition of cell wall synthesis. Antimicrobials that block protein synthesis by binding to the mRNA are. antisense nucleic acids. Nucleotide or nucleoside (acids/analogs/antisense) are antimicrobial agents that mimic the chemical structure of DNA building blocks.
Why are some antibiotics resistant to erythromycin?
Some bacteria are resistant to erythromycin as a result of mutation of their ribosomal RNA.
What is the term for a drug that is developed to combat resistance?
selective toxicity. Semisynthetic drugs developed to combat resistance are often called (analog/second generation/synergist) drugs. second generation. Secondary infections that result from the killing of some of the normal microbiota are called (antagonism/superinfections/resistance). superinfections.
What is resistance drug?
resistance. Any drug that acts against a disease is called a (n) (analog/antibiotic/chemotherapeutic) agent. chemotherapeutic agent. Most drugs that inhibit the synthesis of the cell wall act by.
What is selective toxicity?
Selective toxicity refers to the ability of an antimicrobial to kill microbes with minimal damage to the host. In order to gain FDA approval for your drug, you must elucidate its mechanism of action (MOA). MOA refers to the particular pathway/ process/molecule that will directly be impacted by your drug.
Natural Products Structural Diversity-II Secondary Metabolites: Sources, Structures and Chemical Biology
Sheo B. Singh, ... Fernando Peláez, in Comprehensive Natural Products II, 2010
Dynamics of Proteins and Nucleic Acids
Arnab Mukherjee, Wilbee D. Sasikala, in Advances in Protein Chemistry and Structural Biology, 2013
Amino Acids, Peptides and Proteins
Timothy J. Montavon, Steven D. Bruner, in Comprehensive Natural Products II, 2010
Other Anticancer Drugs Targeting DNA and DNA-Associated Enzymes
Carmen Avendaño, J. Carlos Menéndez, in Medicinal Chemistry of Anticancer Drugs (Second Edition), 2015
Antibiotics
Actinomycin D or dactinomycin (30.5.7 ), which is isolated from Streptomyces species, is the most significant member of the actinomycins, a family of structurally related chromopeptide antibiotics with a common phenoxazine chromophore attached to two pentapeptide lactone moieties, vary in their amino acid content.
Antineoplastic Agents
One of the older anticancer drugs and most commonly used in treatment of a variety of cancers is dactinomycin ( 28.1.108). It is the most significant member of actinomycin antibiotics, which are isolated from Streptomyces parvulus soil bacteria. It is a compound composed of two cyclic peptides attached to a phenoxazine ring system.
Apoptosis and Programmed Cell Death in Health and Disease
Apoptotic cells exhibit a reduced DNA stainability, independent of the type of DNA-specific fluorochrome applied, be it PI or dyes from the phenanthridinium, acridine, actinomycin, and chromomycinone groups (A1, A2, C20, D2, T4).
What is actinomycin used for?
Although not useful in antibiotic therapy, it remains a commonly used chemotherapeutic agent for the treatment of a variety of cancers. Actinomycin was first isolated from Streptomyces antibioticus and is produced by many Streptomyces strains. 5 The actinomycins are a family of bicyclic chromopeptide lactones sharing the chromophoric phenoxazinone dicarboxylic acid to which are attached two pentapeptide lactones of nonribosomal origin.6 Actinomycin D ( 2) acts as a transcription inhibitor, binding to DNA duplexes at the transcription initiation complex and preventing RNA polymerase elongation.7 Conformation of the molecule is extremely well adapted for intercalation into a right-handed DNA helix, favoring the establishment of hydrophobic interactions that stabilize the DNA/antibiotic complex.8–11 More than 41 actinomycins have been reported, mainly with variations in the peptide portion of the structures. The class is represented by actinomycin D ( 2 ), which is perhaps the most deeply studied member of the series.
What was the first antibiotic used to treat tuberculosis?
The discovery of this broad-spectrum antibiotic in 1944 was highly relevant due to its application as the first antibiotic useful to treat tuberculosis. 12 This discovery was followed by successive discoveries of many aminoglycosides such as neomycin, kanamycin, and gentamycin for the treatment of Gram-negative infections.
What is erythromycin 4?
Erythromycin ( 4) was the first macrolide introduced in the clinic 14 and was originally used as an alternative therapy to β-lactams to treat infections with Gram-positive pathogens such as Staphylococcus spp. and Streptococcus spp. This compound, produced by a strain of Saccharopolyspora erythraea, consists of a 14-membered macrocyclic lactone.
What did Brotzu find?
Brotzu’s findings were published in a rather obscure Italian University review, and it was pure chance that it came to the attention of a group of antibiotic hunters in Oxford. They then found out that the Acremonium produces not just one, but several related antibiotics.
What is doxorubicin?
Doxorubicin ( 18) produced by Streptomyces peucetius is a member of the anthracycline family of antibiotics that have been successful treating various forms of cancer. 32–34 These compounds have been used in the clinic, but the mode of action is still uncertain.
What is ivermectin used for?
Although ivermectin was discovered and first developed for the treatment of parasitic infections in animals, it was subsequently approved for the treatment of river blindness in humans and has been tremendously successful in eliminating this debilitating disease in parts of Africa. 29–31.
What is the role of amphotericin B in the cell membrane?
This binding disrupts the integrity of the membrane, causing the loss of ions, small molecules, and oxidative enzymes, resulting in cell death.
Why are antimicrobials toxic to all cells?
because it is active against both prokaryotic and eukaryotic cells. Because there are only very slight differences in the DNA of prokaryotic and eukaryotic cells, antimicrobial drugs that target nucleic acid synthesis can be very toxic to all cells.
Which drugs block the transport of NAG and NAM from the cytoplasm?
nucleic acid synthesis. cell wall synthesis. cell wall synthesis. Drugs such as bacitracin, which block the transport of NAG and NAM from the cytoplasm, are effective in preventing cell wall synthesis.
What is the magic bullet?
the concept of chemotherapy. sulfanilamide. Paul Ehrlich's idea of the "magic bullet" was the first step in the field of chemotherapy and resulted in the use of arsenic compounds in the treatment of syphilis. Sulfanilamide was the discovery of Gerhard Domagk.
What is the cell wall of a Gram positive bacteria?
The cell walls of Gram-positive bacteria have a thick peptidoglycan component.The damage from beta-lactam action affects a greater proportion of the Gram-positive cell walls than Gram-negative cell walls. YOU MIGHT ALSO LIKE... 12.
How long does it take for mycobacteria to reproduce?
Mycobacteria do not have cell walls. Mycobacteria reproduce very slowly. Mycobacteria take 12-24 hours to reproduce, in part due to their complex cell walls. Therefore, drugs against these bacteria must be administered over long periods of time.
Do bacteria have more efflux pumps?
Resistant bacteria may have a greater number of efflux pumps on their cell surfaces. Some bacteria can decrease the specificity of their efflux pumps, increasing the number of different antibiotics the pumps can eliminate. Some bacteria can change the chemical structure of the antibiotic.
Which cell is most susceptible to polyene?
Fungal; bacterial. Fungal cells are the most susceptible to the activity of polyene drugs due to the presence of ergosterol in their cytoplasmic membranes. Bacterial cells are the least susceptible because they usually have no sterols in their membranes.
What is dactinomycin D?
Dactinomycin (actinomycin D, Cosmegen Lyovac) Dactinomycin is a type of chemotherapy. It is also known as actinomycin D or by its brand name Cosmegen Lyovac. You might have it as a treatment for a number of different cancer types such as: Wilm's tumour. Ewing's sarcoma.
What do they check before and during a chemo treatment?
You have blood tests before and during your treatment. They check your levels of blood cells and other substances in the blood. They also check how well your liver and kidneys are working.
How long can you stay off live shots?
Don’t have immunisations with live vaccines while you’re having treatment and for up to 12 months afterwards. The length of time depends on the treatment you are having. Ask your doctor or pharmacist how long you should avoid live vaccinations.
How do you know if you have an infection?
Symptoms include a change in temperature, aching muscles, headaches, feeling cold and shivery and generally unwell. You might have other symptoms depending on where the infection is. Infections can sometimes be life threatening. You should contact your advice line urgently if you think you have an infection.
How to get rid of tiredness?
Various things can help you to reduce tiredness and cope with it, for example exercise. Some research has shown that taking gentle exercise can give you more energy. It is important to balance exercise with resting.
How long does it take for diarrhoea to go away?
Contact your advice line if you have diarrhoea, such as if you've had 4 or more loose watery poos (stools) in 24 hours. Or if you can't drink to replace the lost fluid. Or if it carries on for more than 3 days.
How to control sickness?
Feeling or being sick is usually well controlled with anti sickness medicines. Avoiding fatty or fried foods, eating small meals and snacks, drinking plenty of water, and relaxation techniques can all help.