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Body fluid compartments
Movement of water between body compartments
Acid-base disturbances: Pathology review
Diabetes insipidus and SIADH: Pathology review
Electrolyte disturbances: Pathology review
Renal failure: Pathology review
Acyanotic congenital heart defects: Pathology review
Adrenal masses: Pathology review
Bacterial and viral skin infections: Pathology review
Bone tumors: Pathology review
Coagulation disorders: Pathology review
Congenital neurological disorders: Pathology review
Cyanotic congenital heart defects: Pathology review
Extrinsic hemolytic normocytic anemia: Pathology review
Eye conditions: Inflammation, infections and trauma: Pathology review
Eye conditions: Refractive errors, lens disorders and glaucoma: Pathology review
Headaches: Pathology review
Intrinsic hemolytic normocytic anemia: Pathology review
Leukemias: Pathology review
Lymphomas: Pathology review
Macrocytic anemia: Pathology review
Microcytic anemia: Pathology review
Mixed platelet and coagulation disorders: Pathology review
Nasal, oral and pharyngeal diseases: Pathology review
Nephritic syndromes: Pathology review
Nephrotic syndromes: Pathology review
Non-hemolytic normocytic anemia: Pathology review
Pediatric brain tumors: Pathology review
Pediatric musculoskeletal disorders: Pathology review
Platelet disorders: Pathology review
Renal and urinary tract masses: Pathology review
Seizures: Pathology review
Viral exanthems of childhood: Pathology review
Adrenal insufficiency: Pathology review
Central nervous system infections: Pathology review
Childhood and early-onset psychological disorders: Pathology review
Congenital gastrointestinal disorders: Pathology review
Diabetes mellitus: Pathology review
Environmental and chemical toxicities: Pathology review
Gastrointestinal bleeding: Pathology review
GERD, peptic ulcers, gastritis, and stomach cancer: Pathology review
Inflammatory bowel disease: Pathology review
Medication overdoses and toxicities: Pathology review
Obstructive lung diseases: Pathology review
Pneumonia: Pathology review
Psychiatric emergencies: Pathology review
Shock: Pathology review
Supraventricular arrhythmias: Pathology review
Traumatic brain injury: Pathology review
Ventricular arrhythmias: Pathology review
Congenital TORCH infections: Pathology review
Jaundice: Pathology review
Respiratory distress syndrome: Pathology review
Autosomal trisomies: Pathology review
Cystic fibrosis: Pathology review
Disorders of sex chromosomes: Pathology review
HIV and AIDS: Pathology review
Miscellaneous genetic disorders: Pathology review
Papulosquamous and inflammatory skin disorders: Pathology review
Anxiety disorders, phobias and stress-related disorders: Pathology Review
Developmental and learning disorders: Pathology review
Eating disorders: Pathology review
Mood disorders: Pathology review
Pharmacodynamics: Agonist, partial agonist and antagonist
Pharmacodynamics: Desensitization and tolerance
Pharmacodynamics: Drug-receptor interactions
Pharmacokinetics: Drug absorption and distribution
Pharmacokinetics: Drug elimination and clearance
Pharmacokinetics: Drug metabolism
Androgens and antiandrogens
Estrogens and antiestrogens
Miscellaneous cell wall synthesis inhibitors
Protein synthesis inhibitors: Tetracyclines
Cell wall synthesis inhibitors: Penicillins
Antihistamines for allergies
Non-steroidal anti-inflammatory drugs
Antimetabolites: Sulfonamides and trimethoprim
Cell wall synthesis inhibitors: Cephalosporins
DNA synthesis inhibitors: Fluoroquinolones
DNA synthesis inhibitors: Metronidazole
Miscellaneous protein synthesis inhibitors
Protein synthesis inhibitors: Aminoglycosides
Bronchodilators: Beta 2-agonists and muscarinic antagonists
Bronchodilators: Leukotriene antagonists and methylxanthines
Pulmonary corticosteroids and mast cell inhibitors
Anticonvulsants and anxiolytics: Barbiturates
Anticonvulsants and anxiolytics: Benzodiazepines
0 / 53 complete
0 / 5 complete
0 / 9 complete
Ampicillin and Amoxicillin
Ampicillin, Amoxicillin, Piperacillin, Ticarcillin
Monobactams & Carbapenems
Nafcillin, Oxacillin, Methicillin & Dicloxacillin
clinical use p. 185
Haemophilus influenzae p. , 140
Helicobacter pylori p. , 144
Lyme disease p. 144
mechanism (diagram) p. 184
prophylaxis p. 194
Penicillins are antibiotics that got their name from the Penicillium mold, from which they were originally extracted.
They belong to the pharmacological group of beta-lactam antibiotics.
What all beta-lactams have in common is a beta-lactam ring in their structure, which gives them their name, and also the mechanism of action - the inhibition of cell wall synthesis in bacteria.
So, our body consists of multiple eukaryotic cells, while bacterias are prokaryotic, meaning they are primitive, single cellular organisms.
Most have a slimy capsule made out of polysaccharides and a cell wall which encapsulates and protects the bacteria like a suit of armor and offers structural support.
Bacterial cell walls are made of a substance called peptidoglycan, or murein.
Peptidoglycan is a molecule composed out of long strands of amino polysaccharides running in parallel.
These are made of segments of N-acetylglucosamine, or NAG, and N-acetylmuramic acid, or NAM, in an alternating pattern - so, NAG, NAM, NAG, NAM, and so on, like a pearl necklace.
At the tips of the NAM subunits are tetrapeptide and pentapeptide chains, protruding from NAM subunits.
These peptide chains can link to other peptide chains from the neighboring strands through a process known as transpeptidation.
This is carried out by an enzyme called DD-transpeptidases, or penicillin binding proteins, or PBPs.
Now these enzymes are like locks and there are specific binding area for the pentapeptides keys to fit into.
Once the key goes in the lock, the PBP enzymes fuse them together, creating a stable link between the two amino polysaccharide strands and strengthen the cell wall.
In essence, all beta lactam antibiotics, like the penicillins, somewhat resemble the tetrapeptide chains.
Inside the bacteria, PBP enzymes will mistakenly bind to the beta lactams antibiotic molecule instead of a tetrapeptide and stick inside the PBP forever, like chewing gum in a keyhole, permanently disabling it.
As more and more of PBPs gets disabled, the crosslinking fails to occur, and the wall becomes weak and unstable.
If the affected bacteria attempts to divide, their cell wall will collapse, killing them in the process!
Now, some bacteria have developed resistance to beta lactam antibiotics.
The most notable is the notorious staphylococcus aureus, which evolved an enzyme called beta lactamases or penicillinases that breaks down the beta lactam ring within the antibiotic, rendering it ineffective.
In response, we started adding beta lactamase inhibitors, such as clavulanic acid, that would bind to beta lactamases and inactivate them, like the gum into the keyhole.
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