SC NATS 1670 Lecture & Written Notes PDF

FACTORS THAT AFFECT THE EMERGENCE OF DISEASES " Microbial adaptation drug resistance Human behaviour international travel sexual activity >Human susceptibility to infection poverty, malnutrition, poor sanitation ↳Changing ecosystems global warming Iclimate and weather ↳Wars (Polio in Afghanistan a...

FACTORS THAT AFFECT THE EMERGENCE OF DISEASES " Microbial adaptation drug resistance Human behaviour international travel sexual activity >Human susceptibility to infection poverty, malnutrition, poor sanitation ↳Changing ecosystems global warming Iclimate and weather ↳Wars (Polio in Afghanistan and Syria) - ANTIMICROBIAL DRUG RESISTANCE -Mycobacterium tuberculosis ↳ antibiotics ↳ helped -> Acinetobacter pathogen ↳ spread > Pseudomonas - -> ↳ through aeruginosa Staphylococcus aureus 40 % almost all is resistant to resistant hospitals antib 10+ (C) against eliminate bacteria Klebsiella pneumoniae -> => to a lot of He antibiotics SURGICAL TREATMENT FOR INFECTIOUS DISEASE: Back to pre antibiotics time -> infected remove parts of the lung in tuberculosis AMicrobes are outsmarting antibiotics Disease-causing bacteria colonized living tissue Penicillin kills bacteria (weakening walls) ->When walls collapse, bacteria die -> -> ->microbes reproduce by dividing into t wo replicating themselves each time random genetic changes in all livings are seen more frequently in microbes (reproduce rapidly as every 12 minutes) ->when enables a microbe to fend off an antibiotic -attack, there is a new stronger microbe ->resistant microbes can multiply quickly without competition ->Mutations, THE DEVELOPMENT OF T RESISTANT ORGANISM POPULATIONS - -> most cases , leave Slow evolution -> take ↳ -> If years When used 124 any -> for the Improve inappropriately hours later sanitation antibiotics antibiotics results is , resistance available resistant In alone bacteria drug for to be treatment strains resistant take , over strength developed takes a during in your while one night flow WHO SHOULD BE BLAMED FOR ANTIBIOTICS RESISTANCE? Earn financial alds extra ↓ • Misuse/abuse of antibiotics - farmers ( 80% of all antibiotics are used on factory farm animals) ⑤ - used as growth promoters, chicken farms used this antibiotics to gain weight (faster growth) - How antibiotics concentration ③health workers -> = to chance Increase the they problem) main come with resistance - antibiotics are recommended immediately and given right away ex: streptococcus obtains m protein and when developed immunity to this pathogen, once it is gone the, the immune system will turn against your heart rheumatic fever ↳ ↳> diseases auto immune - ↳ -> can that disease get , affecting treatment heart right away , joints , skin , brain mean develop antibiotic are meant - patients -hospitals 0 ↳ to avoid mutagens used be used for drugs as - for cancer COaX mutations IN att periods bacterial metal like drugs making = resistance hospital - /drugs A inflammatory the + antibiotics isENE (bacterial ceins) • Antibiotics policy in third world countries ↳ some countries ↳s treated ↳ greater for give it one exposure over the counter day (temporally fix) to antibiotics resistance - -> agrie rete twate • Antibiotics were developed from "natural product" ↳bacteria are exposed to antibiotics for billions of years part * of the Alexander evolution of microbe and other organisms flaming ↳selective pressure (induced evolution) -microbial “genetic internet” ↳ exchange of plasmid that often contain resistance genes for multiple drugs plasmids expressing genes -> these to used are for can find their pathogenic bacteria genes way from antibiotic non-pathogenic resistance and bacteria only necessary- when THE DEVELOPMENT OF RESISTANT ORGANISMS IN POPULATIONS ↳Resistance by bacteria acquired 2 ways New mutations if chromosomal genes - - slow process multiple steps Gene transfer - aacquisition of - fastest A-plasmids transformation , transduction conjugation , via and * cells whest bacterial sense Kill can IS going 76 them ⑤ -> batter cellslike gramnegative are to going pick up by mutations e ANTIBIOTIC DRUG RESISTANCE MECHANISM INACTIVATION OF ANTIBIOTICS ↳ Enzymes that alter th antibiotic to inactivate its function 2x : MODIFICATION ↳ modify ADATION - : Chloramphenicol a : acetyl drug by adding beta-lactamase ↳ enzymes that know a transferase certain chemical (penicillinase) how to destroy the beta lactam ring • Gram positive bacteria release the beta-lactanese enzyme from the c into the extracellular environment where it inactivates the drug bef enter the bacteria cell • in contrast, gram-negative bacteria retain the beta-lactamese with periplasmic space resulting in a more efficient mechanism than grampositive bacteria • the destruction of the betalactam ring of the antibiotic renders inca of binding penicillin, binding protein • Becomes resistant to that drug Clavulinic acid rescues the effect of the beta lactamases ↳ Binds strongly to beta lactamases -inhibits their activity ↳Synergistic effect with penicillin and cephalosporins > beta-lactamase -> clavulinc and can can ALTERED TARGET SITES destroy Inhibit penicillin-> enzymes beta-lactamase -> work enzymes stop again working The bacterial cell can alters or eliminate the target the sit for the antibiotics ->ex. Penicillin binding protein (transpeptidase) -> bacterial cells are trying to escape Ex. Production of altered penicillin binding proteins can still cross link the peptidoglycan layers of the cell wall but have a reduced affinity for beta-lactamase antibiotics thus rendering the bacteria resistant to the effects. Glen Collin and other beta-lactam agents -> -> If an organism gains resistant to an antibiotic that acts on the ribosome the target site of binding for the drug is caned and the drug no longer bunds another mechanism need five drugs Deta-lactam all -> to -> -> a destruction penicillin that beta are => by the lactam are NDM the are - 1 to going most be subjected important antibiotics around colistin ↳ a antibiotics -> polymyxin In high toxicity antibiotics * baserlaphage better than drug regular RETARDING RESISTANCE Limit use of antimicrobials to necessary cases High concentration of drug and long treatment Use antimicrobial agents in combination E > Combination ↳ Developing therapy , sulfer drog new variations if existing drugs -> novel side chains added to original molecules ↳ Developing of drugs for new targets ↳ Better diagnostic tools (DNA based) when drugs their have constant are structure ouhear own in bacteriophage survive evoluti bacterial , cell to Some key notes: • child mortality in the 1900s was quite high • as vaccines and other antibiotics come into play, the life expectancy in the USA from 1900 - 1928 had gone up approximately 25% • world population from 1950 - 20150 have also increased by billions; from 3 billion to about 6 billion • when AIDS was introduced, life expectancy went down to the age of 50 • from the 30 million people infected with HIV, less than 1 million of those people receive the drugs to cure them