Exam 1 Flashcards

Question

Phenicols

Answer 1

Chloramphenicol | Florfenicol

Answer 2

Cefalexin/Cephadroxil Cefpodoxime/Ceftiofur Cefovecin, Cefquinome

Answer 3

Erythromycin | Tiamulin, Tilmicosin

Answer 4

Lycomycin/Clindamycin

Answer 5

Streptomycin Gentamicin/Neomycin Amikacin

Answer 6

Colistin/Polymixin

Answer 7

Metronidazole

Answer 8

``` CARBAPENEMS- Imipenem/meropenem Ertapenem/doripenem GLYCOPEPTIDES- Vancomycin/Teicoplanin OXAZOLIDINONES- Linezolide ```

Answer 9

* Natural – produced by fungi and bacteria (antibiotics) * Semi-synthetic – chemically altered natural compounds * Synthetic – chemically designed by man

Answer 10

``` •Bactericidal drugs- kill •Bacteriostatic drugs- inhibt growth -- Some drugs may be bactericidal or bacteriostatic depending on: --> Drug concentration --> Presence of other drugs --> Bacterial species ```

Answer 11

* Penicillin G / V (narrow spectrum, Gram +) * Methicillin, oxacillin(antistaph penicillins) * Aminopenicillins (more active against Gram-) * Carbooxypenicillins (active against Pseudomonas and Proteus)

Answer 12

* 1st generation (mainly Gram+) * 2nd generation (more active against Gram-) * 3rd generation (broader spectrum incl. Pseudomonas) * 4th generation (both Gram+ and Gram+, less susceptibile to β-lactamases)

Answer 13

• Imipenem, meropenem (highly resistant to β-lactamases, injectable)

Answer 14

Good- •Penicilins •Aminopenicilins Bad- •Metronidazole

Answer 15

``` Good- •Amoxicillin/clavulanate •Cephalosporins •Sulfonamides •Aminoglycosides •Fluoroquinolones ``` Bad- •Penicilins •Aminopenicillins •Metronidazole

Answer 16

``` Good- •Amoxicillin/clavulanate •Cephalosporins •Fluoroquinolones •Aminoglycosides •Sulfonamides ``` ``` Bad- •Metronidazole •Penicillins •Lincosamides •Macrolides ```

Answer 17

``` Good- •Penicilins •Aminopenicillins •Lincosamides •Metronidazole ``` Bad- •Amino glycosides

Answer 18

--Time-dependent antibiotics (index: time over MIC) are most effective if their concentration is maintained above the MIC as long as possible (at least 50% of the dosing interval for beta-lactams). --Concentration-dependent antibiotics (index CMAX/CMI) are most effective if they reach a high concentration compared to the MIC at the site of infection, while the time that they maintain this concentration is less important. • Many antibacterial classes (e.g. macrolides, lincosamides and tetracyclines) fall into a third category, where efficacy depends both on concentration and time (index AUC/CMI).

Answer 19

Time-dependent Time>MIC --> Penicillins --> Cephalosporins AUC/MIC - -> Macrolides - -> Lincosamides - -> Tetracyclines Conc.-dependent Cmax/MIC --> Aminoglycosides --> Fluoroquinolones* *The efficacy of fluoroquinolones is also predicted by AUC/MIC > 100 for treatment of Gram-negative bacterial infections In order to maximize clinical efficacy: • High doses for concentration-dependent drugs • Regular dose intervals for time-dependent drugs

Answer 20

both are necessary and relation is positive for both

Answer 21

good for one, no problem for the other (eg. Most of the intestinal flora)

Answer 22

one takes advantage of the other

Answer 23

``` Facultative pathogenic • Endogenic infection ---- E. coli ---- S. aureus • Exogenic infection Obligate pathogenic ```

Answer 24

* Balanced: damage with recovery | * Unbalanced: high damage/death

Answer 25

• Invasion and multiplication of micro-organism, ev. with disease

Answer 26

``` • Structural and functional damage • Clinical/Subclinical --- Subclinical ex: Mastitis (in dairy cattle, reduced milk production) • Opportunistic • Septicaemiae/bacteraemia ```

Answer 27

``` • Not in all bacteria • Motility • H-antigens • Composition • Flagellin • Mainly in Gram-negative bacteria Ex: Listeria monocytogenes ```

Answer 28

Pili = fimbriae = fibrillae • Adhesion • F-antigens Ex: E. coli: ETEC, F4, F5,... Special pili = sex pili • Bacteria conjugation (plasmid transfer)

Answer 29

Extracellular • Thromboses, local use of nutrients/oxygen • Immunological reaction: oxygen radicals/enzymes by macrophages and neutrophils Facultative intracellular • Cell lysis Obligate intracellular • Cell lysis

Answer 30

- Capsule - Proteins that circumvent innate immunity - Iron uptake - Production of extracellular enzymes • Hyaluronidases • Collagenases • Fibrinolysins • Coagulases • Hemolysins • Leucocidins

Answer 31

``` • Not in all bacteria • Polysaccharides-proteins • Virulence factor ---> Colonisation ---> Invasion ---> Adhesion ---> Protection against : • phagocytosis • Complement • Environmental protection • Capsular antigens (K-antigens) ```

Answer 32

• Bacterial metabolites ---> Clostridium • Proteins with in general high molecular weight (are thus antigenic) -- Exceptions: eg. Heat stable enterotoxin (Sta, Stb) of ETEC • Types I, II, III • ‘Anatoxins’: chemically treated (eg. formalin) toxins --Toxicity:- -- Antigenicity: + (vaccination)

Answer 33

• Type I -Bind receptor - Disturbance of cell metabolism • Examples: • Sta of ETEC • Clostridiumperfringens • Staphylococci and Streptococci • Type II - Cell wall damage - Staphylococcus aureus: alfa-toxin (hemolysis) - Actinobacillus pleuropneumoniae: Apx Toxins (pore forming) • Type III - Intracellular toxins - A component: goes IC - B (binding) component: binds membrane • Examples: • Heat labile toxin (LT) of ETEC • Shiga toxin (ST) of VTEC, EHEC • Botulinum toxin • tetanospasmin

Answer 34

``` • Cell wall components • Damage +++ • Immune reaction + • LPS (heat stable) -- Protection against • Toxic products • Complement -- Acts as an endotoxin • Infection with a Gram-negative bacterium • Fever, general sickness • Tissue damage • Cardiovascular shock • Death ```

Answer 35

• Lipoteichoic acid (LTA) --- Example: Staphylococcus aureus • Lipoarabinomannan (Mycobacteria) (LAM) • Peptidoglycan • Fever, general sickness • Tissue damage • Cardiovascular shock • Death

Answer 36

``` Spheric structures • Lipid membrane (part of outer membrane) • Contain • Enzymes • exotoxins • DNA(Transformation) • Signalmolecules ``` ``` Roles • Pathogenesis • Signaling (quorum sensing) • Excretion of toxic products • Killing of competitors • Immunomodulation • Excretion of bacterial toxic products • Transformation ```

Answer 37

``` •Hard to treat • Bacteria in sessile form included • Composition: -- Polysaccharides -- Proteins -- Nucleic acids (DNA) • Bacterial persistence (endocarditis) • Reduction of host immunity • Local damage • Reduced susceptibility to antibiotics • Different surfaces: Catheters, pipelines (drinking water farms),... ```

Answer 38

* (Lipo)proteins-porins * Role: * Pathogenesis * Adhesion * Iron uptake * Physiological role

Answer 39

- By the cell wall proteins - In first line defense (innate defense) • No free iron in the body • Intracellular: • Epithelial cells: ferritin • Erythrocytes; hemoglobin • Muscular cells: myoglobin • Serum: transferrin • mucosae: lactoferrin • Infection: neutrophils ---> lactoferrin • Pathogenic bacteria can circumvent iron restriction • Alternative for iron • E.g. manganese in Borrelia burgdorferi • Expression of iron uptake system under iron restrictive conditions • Siderophorereceptor (neonatal E.colisepticaemiae) • Transferrine / lactoferrine receptor ** • Hemoglobinereceptor** (**Actinobacillus; pleuropneumoniae)

Answer 40

No complement activation • Sialic acid (E. coli) on the surface • Enzymes that degrade the complement system No lysis of bacterium • LPS • Capsule Inhibition of the complement mediated inflammation • Membrane vesicles • Expel of complement factors • Intracellular multiplication

Answer 41

Phagocytes • Macrophages • Neutrophils NK cells

Answer 42

* Extracellular bacteria * Capsule * Metabolites-exotoxins * Biofilm * Facultative intracellular

Answer 43

- Vaccines with living organisms (attenuated) - Vaccines without living organisms • DNA vaccines • Vaccines based on antigen ---> Toxoid: inactivated exotoxin • Isolated from bacterium or recombinant ---> Bacterins:inactivatedcompletebacterium ---> Subunit vaccines • Fimbriae, surface antigens • Isolated fro; bacterium or recombinant

Answer 44

``` Attenuation • Serial passages in Vitro (Pasteur & rabies) • Genetic manipulation - Culture + mutagen - Deletion mutants - Vector vaccines - Not so frequent against bacteria • BCG vaccine (TB) • Bordetellabronchiseptica • E. coli (APEC, ETEC swine) - Both cellular and humoral immunity - One vaccination • Care: no antibiotic treatment!! - Fast induction of protection - Vector vaccines • use of eg. attenuated Salmonella • Expression of immunogen epitope ```

Answer 45

* In general a lot of antigen present * Frequently an adjuvant added * 2 administrations with 3-4 w interval * Safe * Mainly production of antibodies *3 Main Types - Toxoid • Exotoxin + formol • Recombinant - Bacterins • Complete bacterium • Note: autovaccine ---> Bacterium isolated from diseased animal & inactivation (formol) ---> Care: side effects - Subunit • Fimbriae (ETEC) • Iron capture systems; transferrin binding proteins (APP)

Answer 46

• Bacterin + toxoid • Subunit + toxoid ---> ETEC: Fimbriae and LT

Answer 47

``` To equip you with information on parasites you will need as a veterinarian in North America: • which cause disease • clinically relevant • which are zoonoses • diagnostic tools • minimize impact on production • treatments used daily in practice • sustainable interventions to manage ```

Answer 48

helminths, ectoparasites (Arthropods) and protozoa.

Answer 49

SIS!!!! • Host Species • Site of Infection • Size of parasite

Answer 50

* Parasiticides * Sustainable management of the host * Management of the environment * Life cycle is used to determine treatment and prevention

Answer 51

``` Phylum Nemathelminthes (Roundworms) Class Nematoda (Roundworms) Phylum Platyhelminthes (Flatworms) Class Cestoda (Tapeworms) Class Trematoda (Flukes) Phylum Arthropoda Class Insecta Class Arachnida Subkingdom Protozoa Phylum Mastigophora Phylum Apicomplexa - Five orders (Helminths) Phylum Nemathelminthes (Roundworms) Class Nematoda (Roundworms) Phylum Platyhelminthes (Flatworms) Class Cestoda (Tapeworms) Class Trematoda (Flukes) ```

Answer 52

``` Helminths Phylum Nemathelminthes (Roundworms) Class Nematoda (Roundworms) ex: Ascaris suum • Free-living or parasitic • Elongate/cylindrical • Alimentary canal present • Sexes usually separate • Life cycle direct or indirect ```

Answer 53

``` Helminths Phylum Platyhelminthes (Flatworms) Class Cestoda (Tapeworms) ex: Dipylidium caninum • Flat body and no alimentary canal • Scolex (holdfast organ) • Strobila (body) with proglottids • Each proglottid- hermaphroditic • Indirect life cycle • Types of characteristic larval stages ```

Answer 54

``` Helminths Phylum Platyhelminthes (Flatworms) Class Trematoda ex: Fasciola hepatica • Dorso-ventrally flattened • Leaf-like • Oral and ventral suckers • Indirect life cycle- molluscan IH • Usually genitally independent ```

Answer 55

``` Phylum Arthropoda Class Insecta & Class Arachnida Insects • Flies(Diptera) • Fleas(Siphonaptera) • Lice(Phthiraptera) • Hemiptera --> Identification • Adults: 3 pairs of legs • Head, thorax, abdomen • Antenna ``` ``` Arachnids -- Acari • Ticks • Mites --> Identification • Nymphs and adults: 4 pairs of legs • Larvae: 3 pairs of legs • Body: cephalo-thorax and abdomen • No antennae, but palps ```

Answer 56

``` Subkingdom Protozoa Phylum Mastigophora Phylum Apicomplexa - Five orders ex: Giardia • Unicellular, eukaryotic animals • Classified based on their mode of locomotion • Locomotion is accomplished by: Pseudopodia Flagella Gliding movements Cilia ```

Answer 57

Ingestion: • Giardia, Balantidium coli, Toxoplasma gondii, Cryptosporidium, Cestodes, some Nematodes, some Trematodes Skin or mucosal penetration: • Hookworm, Strongyloides stercoralis; schistosomes Transplacental (prenatal) • Toxoplasma gondii, Toxocara canis, Strongyloides stercoralis Transmammary (milk) • Toxocara canis, T. cati, Ancylosotma caninum Arthropod bite (vector): • Babesia, heartworm, Leishmania, Trypanosomes Sexual contact • Tritrichomonas foetus

Answer 58

``` • Mechanical or biting mouthparts  • Oral cavity (capsule) • Attachment organs • Suction disk • Biting mouthparts • Direct penetration • Molecular interaction ```

Answer 59

Parasites Target Receptor Trypanosome cruzi Fibroblast Fibronectin & its receptor Leishmania mexicana macrophage Major surface protease (MSP or GP63) & CR2 Babesia spp. Red blood cells C3b receptor Giardia duodenalis Duodenal & jejunal Lectin and epithelium mannose-6- phosphate adherence molecule 1 on disk

Answer 60

``` • Blockage of internal organs: Ascaris, tapeworms, schistosomes, filarial worm • Pressure atrophy: Echinococcus, Cysticerci • Migration through tissues: Helminthic larvae ```

Answer 61

``` • Destructive enzymes: Anasakiasis, schistosome cercariae, hookworms • Endotoxins: African trypanosomes, malaria • Toxic secretions: Tickparalysis ```

Answer 62

• Competition with hosts for nutrients – Diphyllobothrium latum (fish tapeworm) • Interference with nutrient absorption – Giardia duodenalis & Strongylodies stercoralis • Nutrient loss – hookworm, iron loss;

Answer 63

Host immunity • Natural or innate immunity – A defense mechanism that does not depend upon prior exposure to the invader. -- Cytokines and cytokine receptors -- Antimicrobial molecules and pattern recognition receptors -- Cellular defense, phagocytosis • Acquired immunity – conferred by a host’s specific immunity response developed as a result of a previous parasitic infection. • Premunition: resistance to superinfection by presence of parasites in check by host immunity-malaria, toxoplasmosis • Concomitant immunity: a parasite elicits a protection against reinfection, but the parasite itself remains in the host, unaffected by the immune response- schistosomiasis

Answer 64

3 Pathways There are three pathways of complement activation, two initiated by microorganisms without the require- ment for antibody, called the alternative and lectin pathways, and a third initiated by immune complexes, called the classical pathway * all end up with the production of C3b, which is part of C5 convertase which will activate C5 in the downstream chain reaction - end effects = Cell lysis; inflammation; opsonization; clearance of immune complexes • activation factors, C3 and C5 convertase, terminal pathway and MAC, results of complement activation

Answer 65

* Humeral immunity * Primary and secondary humeral immune response * Antibody (type & structure) Two Distinct types of adaptive immune responses: ---> Humeoral immunity is mediated by antibodies secreted by antigen- activated B cells and their progeny plasma cells. ---> Cell mediated immunity is mediated by antigen- activated T cells and the cytokines they secrete. • CD8+Tcellsfunctionas cytotoxic T lymphocytes (CTL • CD4+TH1cellsandactivated macrophages function in DTH (delayed type hypersensitivity) responses.

Answer 66

Activator – binding of Ab to Ag; C1 reactive protein binding Initial complement component – C1q, C1r, C1s, C4, C2 C3 convertase – C4bC2b C5 convertase – C4bC2bC3b *** explained well on pages 30 + 31 in book

Answer 67

Activator – mannan binding lectin (MBL), MBL‐associated serine protease‐2 (MASP‐2) Initial complement component – C4, C2 C3 convertase – C4bC2b C5 convertase – C4bC2bC3b

Answer 68

Functions in normal host without prior expose to invading microbes ``` Includes: • Constitutional factors • Natural barriers & normal flora  Cytokines/Interferons •  Phagocytosis •  Complement ```

Answer 69

Adaptive, specific immune responses are induced by exposure to an antigen(s), the response is specific for the inducing antigen(s), and immunologic memory is generated. --Consists of antibody response (humoral) and lymphocyte‐ mediated response (cell‐mediated) response – tailored to particular microbial infection and characterised by memory

Answer 70

Making one species innately susceptible and another resistant to certain infections:  Genetic – between species  Age – the young more susceptible  Metabolic factors – hypoadrenal & hypothyroid states  Neuroendocrine factors  Environment – malnutrition, poor living conditions, overcrowding

Answer 71

--> Induce resistance to viral replication in all cells --> Increase MHC Class 1 expression and antigen presentation in all cells --> Activate NK cells to kill virus-infected cells IFN System ‐ Crucial for Antiviral Defense • Demonstrated in animal models – treatment with anti‐IFN Ab – gene knockout mice • Defective IFN response – reduced ability to contain infection – increased illness and death • Abrogation of IFN‐α/β – global increase in susceptibility – IFN‐γ – modest effect

Answer 72

``` Phagocytic cells • Polymorphonulcear neutrophils • Mononuclear phagocytes (monocytes in blood, macrophage in tissue) • Eosinophils ``` Lymphocytes B cells- Ab producing plasma cells T cells- Cell mediated immune response Help B cells in Ab production Large granular lymphocytes (null cells or NK cells)- Kill other rogue cells in a nonspecific manner against microbes

Answer 73

Engulfment & digestion of infectious agents or other foreign bodies by phagocytic cells Phagocytic cells – phagocytes- major 2: macrophages & neutrophils

Answer 74

• Innate immune system – Pattern recognition receptors (PRRs) • Toll‐likereceptors(TLRs) • Rig‐likereceptors(RLR) • complement – Missing/altered self receptors (NK cells) • Adaptive immune system – Antigen presentation (MHC) – Antibodies – T cell receptors

Answer 75

1) Bacterium becomes attached to membrane evaginations called pseudopodia 2) Bacterium is ingested, forming phagosome 3) Phagosome fuses with lysosome 4) Lysosomal enzymes digest captured material 5) Digestion products are released from cell **Just because a foreign body undergoes phagocytosis, doesn't necessarily mean it is automatically being destroyed or killed. Most are killed, but some pathogens have evolved methods to evade attachment, etc.

Answer 76

Type of phagocyte; Innate immunity - Primarily function to phagocytise and kill extracellular bacterial and yeasts pathogens in acute inflammation. - Live only ~ 1 day in tissues!! - Dead neutrophils are cleaned up by macrophages. Process- --> Neutrophils express receptors for many bacterial and fungal constituents --> Neutrophils bind bacteria, engulf then and destroy them with the toxic content of the neutrophil granules

Answer 77

Type of phagocyte; Innate immunity Process- --> The macrophage expresses several receptors specific for bacterial constituents --> Bacteria bind to macrophage receptors --> Macrophage engulfs and digests bound bacteria

Answer 78

Type of phagocyte; Innate immunity - Eosinophils are an important defense against helminths. - Eosinophils are 1-3% WBC but #’s increase in parasite infections and patients with type I hypersensitivities

Answer 79

• Abundant lymphocytes – 2% of circulating • Large, granular lymphocytes – lack antigen‐ specific receptors found on T and B cells • Number increases rapidly after viral infection ‐ stimulated to divide by IFN produced by infected cells and dendritic cells • On binding release mix of cytokines (IFN γ and TNFα) • Kill cells by releasing perforins and granzymes – perforate membranes and trigger caspase ‐ mediated cell death

Answer 80

• Recognize “altered self” • Two receptor‐binding interactions required for discrimination – one to activate and one to block if cell is not infected • Virus infection‐associated ligand – activating • MHC I molecule – blocking • Virus‐infected cells are prime targets (fewer MHC I on surface) *** good table for visualization on slide 27 of Host Defense 1 ppt

Answer 81

Activator – contact of microbial cell wall with C3 Initial complement component – C3, Factor B, Factor D, & properdin C3 convertase – C3bBb C5 convertase – C3bBbC3b

Answer 82

• the part of an antibody which recognizes an antigen, the antigen-binding site of an antibody • a small region (of 15–22 amino acids) of the antibody's Fab region ** know the type & structure of the antibodies (last ~9 slides of Host 2 ppt)