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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
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for Crohn disease p. 389
cytochrome P-444 and p. 251
fluoroquinolones p. 192
mechanism (diagram) p. 184
meningococci p. 140
Mycobacterium avium- intracellulare p. , 193
prophylaxis p. 194
Pseudomonas aeruginosa p. , 141
Our bodies consist of eukaryotic cells, while bacterias consist of prokaryotic cells.
So, in order to treat bacterial infections we can develop antimicrobials that only target prokaryotic cells while leaving our cells mostly unharmed.
One of these targets is bacterial DNA, and we call these medications DNA inhibitors or nucleic acid inhibitors.
There are plenty of processes and enzymes involved that we can target and the quinolones and fluoroquinolones inhibit an enzyme called DNA topoisomerase.
So there are many different types of topoisomerases but we’ll be looking at topoisomerase II, also called DNA gyrase, and topoisomerase IV.
Both types of topoisomerases cause double strand breaks in DNA, but at different points during mitosis.
Topoisomerase II plays a role in condensing the chromosomes by making a double strand break in the DNA so that it can be more tightly wound, causing a supercoil.
When enough supercoils are induced, the DNA condenses.
Topoisomerase IV plays a role later on, after the chromosome has been replicated, where it causes a double strand break in the DNA so the new DNA strand can be disentangled from the original.
Now, quinolones are created to target bacterial topoisomerases, but it was soon discovered that by adding a fluorine molecule to the quinolones, they become more effective.
So these newer medications, called fluoroquinolones, replaced the older quinolones in most clinical settings.
Common fluoroquinolones include ciprofloxacin, ofloxacin, balofloxacin, levofloxacin, gemifloxacin, and moxifloxacin.
One way to tell a fluoroquinolone apart from other antimicrobials is that they all have the suffix “-floxacin.”
These medications can be taken peroral or via IV, but ciprofloxacin and ofloxacin are also available in otic formulations, while moxifloxacin is also available in ophthalmic solutions.
Now fluoroquinolones are broad spectrum bactericidal antibiotics and ciprofloxacin in particular is widely used.
They are very effective against gram negative bacterias like Enterobacteriaceae, Haemophilus, Legionella, Neisseria, Moraxella, and even Pseudomonas species.
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