(Chapter 10) Principles of Antimicrobial Therapy

A comprehensive set of vocabulary flashcards derived from the lecture on the principles of antimicrobial therapy in microbiology.

How does drug resistance occur in bacteria?

Drug resistance can occur through spontaneous mutations in critical chromosomal genes or acquisition of new genes via horizontal gene transfer. (Drug resistance can happen when cells mutate or pick up new genes.)

What is the mechanism of action of sulfonamides and trimethoprim?

Sulfonamides and trimethoprim block enzymes required for tetrahydrofolate synthesis, which is necessary for DNA and RNA synthesis. (Sulfonamides and trimethoprim are like superheroes that block enzymes needed to make tetrahydrofolate, which is super important for making DNA and RNA.)

How do bacteria develop resistance through horizontal gene transfer?

Bacteria can acquire resistance genes from other species through mechanisms like conjugation, transduction, and transformation. (Bacteria can pick up resistance genes from other species like sneaky little thieves! They do this through things like conjugation, transduction, and transformation.)

What role does the CDC report on antibiotic resistance play?

The CDC report highlights the urgent problem of antibiotic resistance, indicating a potentially catastrophic situation where some infections may become untreatable.

What is the significance of the Therapeutic Index (TI)?

The Therapeutic Index (TI) is the ratio of the dose of the drug that is toxic to humans compared to its minimum effective dose, with a high TI being desirable.

What are the implications of drug resistance for public health?

Drug resistance poses a significant threat to public health by complicating treatment options and increasing the risk of untreatable infections.

What are the challenges in developing new antibiotics?

Challenges include economic factors, the lengthy development process, and the emergence of resistant bacterial strains.

What is Prophylaxis in the context of antimicrobial therapy?

Prophylaxis refers to the use of a drug to prevent imminent infection of a person at risk.

What are the primary targets of antimicrobial drugs against bacteria?

Antimicrobial drugs primarily target the cell wall, cytoplasmic membrane, DNA/RNA, protein synthesis, and folic acid synthesis.

What is the difference between Narrow-Spectrum and Broad-Spectrum antimicrobials?

Narrow-Spectrum antimicrobials are effective against a limited array of microbial types, whereas Broad-Spectrum antimicrobials are effective against a wide variety of microbial types.

What is the role of normal microbiota in the context of antibiotic use?

Normal microbiota help protect against infection, and their disruption by antibiotics can lead to opportunistic infections.(Our friendly gut bacteria are like superheroes that keep us healthy, but antibiotics can mess with them and make us more susceptible to infections.)

What is Minimum Inhibitory Concentration (MIC)?

MIC is the lowest concentration of a drug that inhibits the visible growth of a microorganism.

What is the relationship between the MIC and the effectiveness of a drug?

The MIC indicates the minimum concentration of a drug required to inhibit microbial growth, guiding effective drug selection. (The MIC is like the magic number that tells us how much of a drug we need to stop bad bacteria from growing.)

What is a common consequence of using broad-spectrum antibiotics?

A common consequence is the disruption of normal microbiota, leading to overgrowth of resistant organisms.

What are the three major modes of action of antiviral agents?

The three major modes of action of antiviral agents include inhibiting virus entry or release, blocking transcription and translation of viral molecules, and preventing maturation of viral particles. (Antiviral agents work in three main ways: they stop viruses from getting into our cells, they stop viruses from making more of themselves, and they stop viruses from turning into infectious particles.)

What is the implication of a high therapeutic index?

A high therapeutic index indicates a larger margin of safety between the effective dose and toxic dose of a drug. (A high therapeutic index means a drug is super safe, with a big gap between the dose that works and the dose that’s too much.)

What are superinfections?

Superinfections occur when broad-spectrum antibiotics kill off normal biota, allowing other microbes to thrive.

How do Antibiotics function?

Antibiotics are substances produced by the natural metabolic processes of some microorganisms that can inhibit or destroy other microorganisms.

What is the impact of biofilms on antibiotic effectiveness?

Biofilms often protect bacteria from antimicrobials, making infections harder to treat as antibiotics cannot penetrate the sticky extracellular material surrounding them. (Biofilms are like bacterial shields that protect them from antibiotics. They’re like a sticky blanket that makes it hard for the antibiotics to get in and do their job.)

How can antibiotics contribute to the development of superinfections?

Antibiotics can lead to superinfections by eliminating normal flora, which allows resistant opportunistic pathogens to proliferate.

What is the impact of antibiotic-associated colitis?

Antibiotic-associated colitis occurs when normal gut flora is disrupted, allowing Clostridium difficile to overgrow and cause severe gastrointestinal symptoms.

Define Antimicrobial Chemotherapy.

Antimicrobial Chemotherapy is the use of chemotherapeutic drugs to control infection.

How does the presence of biofilms affect the treatment of bacterial infections?

Biofilms can shield bacteria from antibiotics, making infections more difficult to treat and often requiring alternative therapeutic approaches.

What distinguishes Semisynthetic Drugs from Synthetic Drugs?

Semisynthetic Drugs are chemically modified in the laboratory after being isolated from natural sources, while Synthetic Drugs are produced entirely by chemical reactions.

What is the definition of a Chemotherapeutic Drug?

A Chemotherapeutic Drug is any chemical used in the treatment, relief, or prophylaxis of a disease.

Why is the concept of 'magic bullets' significant in antimicrobial therapy?

The concept of 'magic bullets' emphasizes the need for targeted therapies that selectively kill pathogens without harming the host.

What is the significance of the 'shotgun' approach in antimicrobial therapy?

The 'shotgun' approach refers to the indiscriminate use of antibiotics, which can lead to increased resistance and superinfections. (The ‘shotgun’ approach to antibiotics is like throwing a grenade at a bacteria party - it can cause a lot of damage and make it harder to treat infections.)

What is the significance of the discovery of penicillin?

The discovery of penicillin marked the beginning of modern antibiotics, revolutionizing the treatment of bacterial infections.

What are superinfections and how do they occur?

Superinfections occur when broad-spectrum antibiotics disrupt normal microbiota, allowing opportunistic pathogens to overgrow.

What are Antimicrobials?

Antimicrobials is an all-inclusive term for any antimicrobial drug, regardless of its origin.

What is the function of DRACO in antiviral therapy?

DRACO is a novel antiviral agent being tested that activates cellular apoptosis in infected cells by targeting double-stranded RNA. (DRACO is a new antiviral drug that works by killing infected cells by targeting double-stranded RNA.)

How do beta-lactamases contribute to antibiotic resistance?

Beta-lactamases are enzymes produced by some bacteria that hydrolyze the beta-lactam ring of penicillins and cephalosporins, rendering them ineffective. (Beta-lactamases are enzymes made by some bacteria that break down the beta-lactam ring in penicillins and cephalosporins, making them useless.)

What are the mechanisms by which microbes develop drug resistance?

Microbes can develop drug resistance through new enzyme synthesis, decreased drug permeability, active drug elimination, altered drug binding sites, and metabolic pathway modifications. (Microbes can become drug-resistant in several ways, including making new enzymes, making drugs harder to get into cells, getting rid of drugs before they can do any damage, changing where drugs bind to cells, and changing how cells break down drugs.)

Describe the three major modes of action of antiviral agents.

Antiviral agents act by inhibiting virus entry or release, blocking transcription and translation of viral molecules, and preventing maturation of viral particles.

What is the significance of the CDC's 2013 Threat Report on antibiotic resistance?

The report highlighted the urgent and potentially catastrophic situation of antibiotic resistance, indicating the risk of entering a post-antibiotic era. (The report warned us about the seriousness of antibiotic resistance, saying we might soon run out of effective antibiotics.)

What is the role of probiotics in antimicrobial therapy?

Probiotics are live beneficial microbes that help restore normal microbiota balance and may prevent superinfections.

What is the relevance of the 'shotgun' approach in antimicrobial therapy?

The 'shotgun' approach involves using broad-spectrum antibiotics indiscriminately, which can lead to superinfections and increased resistance.

How does the use of antibiotics in livestock contribute to public health issues?

The use of antibiotics in livestock can lead to the development of resistant bacteria, which may be transmitted to humans through the food supply.

What are the consequences of decreased drug permeability in bacteria?

Decreased drug permeability can result from mutations that alter the bacterial cell surface, leading to reduced susceptibility to antibiotics. (Bacteria can become resistant to antibiotics when their cell surfaces change, making them less permeable to drugs.)

What is the importance of understanding the viral multiplication cycle in treatment?

Understanding the viral multiplication cycle helps in designing targeted antiviral therapies that disrupt specific stages of the virus's life cycle. (Gaining a grasp of the viral multiplication cycle is key to crafting targeted antiviral treatments that target specific stages of the virus’s life cycle.)

What is Horizontal Gene Transfer (HGT) and its role in drug resistance?

HGT allows bacteria to acquire new genes from other species, including those that confer drug resistance through mechanisms like conjugation, transduction, and transformation. (HGT lets bacteria steal genes from other species, including those that make them immune to drugs. This happens through processes like conjugation, transduction, and transformation.)

How do sulfonamides and trimethoprim affect microbial metabolism?

Sulfonamides and trimethoprim inhibit enzymes involved in folic acid synthesis, disrupting DNA and RNA synthesis in microbes.

What is the significance of the discovery of penicillin in medicine?

The discovery of penicillin marked the beginning of the antibiotic era, revolutionizing the treatment of bacterial infections.

What are the challenges faced by anti-helminthic drugs?

Anti-helminthic drugs face challenges due to the complex life cycles of helminths and the need for effective treatment across different stages. (Fighting worms is tough because they have crazy life cycles and we need to treat them at all the different stages.)

What are the key characteristics of broad-spectrum antibiotics?

Broad-spectrum antibiotics are effective against a wide variety of microbial types, making them useful for treating polymicrobial infections. (Broad-spectrum antibiotics are like Swiss Army knives of medicine, fighting off a wide range of germs. They’re great for treating infections caused by multiple types of bacteria.)

What is the primary challenge in treating viral infections?

The primary challenge is that viruses replicate inside host cells, making them difficult to target without harming the host. (The main challenge is that viruses hide inside host cells, making it tricky to attack them without hurting the host.)

What is the impact of biofilms on antibiotic susceptibility?

Bacteria in biofilms exhibit different antibiotic susceptibility profiles compared to free-living bacteria, often making them more resistant to treatment. (Bacteria in biofilms are like little troublemakers that can resist antibiotics, making them tricky to treat.)

What is the importance of the therapeutic index (TI) in drug administration?

The therapeutic index measures the safety margin of a drug, indicating the ratio between effective and toxic doses, with a higher TI being preferred.

What are the primary strategies for treating biofilms?

Strategies include interrupting quorum sensing pathways, using daptomycin, adding DNAse to antibiotics, and impregnating devices with antibiotics prior to implantation.(Here are some cool strategies to fight infections: interrupting quorum sensing pathways, using daptomycin, adding DNAse to antibiotics, and even impregnating devices with antibiotics before implantation.)

What challenges do synthesized quinolones face in treating malaria?

Synthesized quinolones face challenges due to the complex life cycle of Plasmodium, requiring multiple treatments for different stages.

What is the role of quorum sensing in biofilm formation?

Quorum sensing regulates gene expression in bacterial populations, facilitating biofilm formation and maintenance. (Quorum sensing is like a bacterial party trick that helps them make biofilms and stay together.)

What is the role of the Minimum Inhibitory Concentration (MIC) in antimicrobial therapy?

The MIC determines the lowest concentration of a drug needed to inhibit visible growth of a microorganism, guiding effective treatment. (The MIC is like the magic number that tells us the tiniest amount of a drug needed to stop a microorganism from growing. It’s super important for figuring out how to treat infections effectively.)

How do spontaneous mutations contribute to drug resistance in bacteria?

Spontaneous mutations can alter critical chromosomal genes, leading to changes that confer resistance to antimicrobial agents. (Mutations can happen randomly and change important genes in chromosomes. These changes can make bacteria resistant to antibiotics.)

What is the impact of antibiotics on gut microbiota?

Antibiotics can disrupt the balance of gut microbiota, potentially leading to conditions such as antibiotic-associated colitis.

What are the major types of antimicrobial drug producers?

Major antimicrobial drug producers include molds like Penicillium and Cephalosporium, and bacteria like Streptomyces and Bacillus. (Big names in the fight against infections are molds like Penicillium and Cephalosporium, and bacteria like Streptomyces and Bacillus.)

What are the implications of antibiotic resistance for future medical treatments?

The implications include the possibility of returning to a pre-antibiotic era where minor infections could become life-threatening.