By I. Zarkos. Trinity Baptist College. 2018.
While both houses might support some weight of strated in both elderly men and women and this is thought objects placed on the roof purchase tadora 20 mg overnight delivery impotence cure, the first house would be able to to be an important cause of senile osteoporosis as well tadora 20 mg on-line drugs used for erectile dysfunction. The walls of the second The cumulative effect of normal aging, dietary calcium house would only be able to support much lighter loads. While have a tendency to buckle and topple, like an osteoporotic it is commonly held that these effects are mediated by vertebral fracture. Taking the example one step further, stimulation of osteoclasts and inhibition of osteoblasts, consider the first house to be built with bricks made of the exact mechanisms by which they lead to age-related granite and the second house made of bricks of porous bone loss is still not well understood. The sandstone bricks would have a greater ten- dency to crumble with loads, as would the osteoporotic Geometry: effects of osteoporosis on cancellous bone vertebral body. Normal cancellous bone, such as that in the vertebral body, is composed of both horizontal and vertical trabec- Geometry: effects of osteoporosis on cortical bone ulae. These trabecular struts are interconnected, much like the scaffolding used to surround buildings during con- Decreases in bone mass occur throughout the skeleton. While the individual vertical and horizontal mem- the dense cortices of long bones are designed to withstand bers, are, by themselves, important in resisting loads in par- bending and torsional loads, decreases in bone mass would ticular directions (i. Fortunately, long bones interaction that gives cancellous bone its great compres- exhibit a compensatory mechanism to counteract the me- sive strength. In aging individ- Osteoporosis is a disorder in which total bone mass is uals, increased endosteal bone resorption and periosteal reduced yet the quality of the bone is normal. If a micro- bone deposition leads to an overall increased diameter of section of bone were to be biochemically analyzed, it bone. This relationship can be expressed as a formula for would demonstrate a normal ratio of osteoid to mineral. Long Though total bone mass is affected, there is a predisposi- bones resist failure in bending by their areal moment of tion to loss of the horizontal trabeculae. This leads to inertia and in torsion by their polar moment of inertia decreased interconnectivity of the internal scaffolding of properties. Without the support of cross- This phenomenon helps explain why mid-shaft long ing horizontal members, unsupported vertical beams of bone fractures do not occur in a proportionately higher bone easily succumb to minor, normally subcatastrophic, frequency in older than younger individuals. Clinically, this leads to crush of the cancellous bone this same adaptive mechanism does not appear to have a within the vertebral body, recognizable as an osteoporotic role in the vertebral column, as the cortical shell of the compression fracture, which may occur with low-energy vertebral body contributes only about 10% of its overall maneuvers such as picking up a bag of groceries. This The major mechanical role of the vertebral body is to mode of failure is most common in the thoracic spine, withstand compressive loads. Its broad transverse surface which has a physiologic degree of pre-existing kyphosis area and primarily trabecular composition are ideal to ful-. Decreases in cortical bone density with aging within fill these demands. The surface area of the vertebral endplates determines The lumbar spine is normally lordotic. Although ante- the compressive stress concentration imparted to the un- rior wedge compression fractures can occur in this region, derlying cancellous bone. In the best case scenario, sur- more commonly fractures demonstrate uniform compres- face area would be maximized and the compression would sion or central (biconcave) types. One might infer that loads are In some groups of people, the vertebrae are propor- concentrated within the center of the lumbar endplate if tionately smaller. Asians, for example, have a higher rate lordosis is maintained at the time of fracture. This the pattern of failure, and thus the type of fracture, is most is thought to be related to the smaller cross-sectional di- likely influenced by the position of the spine at the time of mensions of the Asian vertebral body. Greater hip axis length in Caucasians corre- sponds to a higher incidence of fracture than the shorter Conclusion lengths in Asians. This most likely is a result of differ- ences in cantilever bending forces, which would be higher As advances in medicine continue to prolong life, an un- with longer hip axis lengths, as well as with the greater derstanding of disorders related to aging becomes increas- body weights notable in the generally larger Caucasian. Osteoporosis and its complications have The pattern of loading is another important influence important detrimental effects on the quality of life of af- on the amount of weight that can be sustained by the ver- fected individuals. Normal spinal balance dictates that a weight- standing of the pathophysiology of the underlying disease bearing plumb line dropped from the base of the occiput process is crucial to effective decision making regarding should fall through the C7 vertebral body, T12–L1 junc- treatment. Recent advances in both the pharmacological tion, and caudally within or just anterior to the sacral (S2) and surgical treatment of osteoporosis and vertebral com- promontory.
People with pre-existing coronary artery disease may need a beta-adrenergic blocking agent (eg order tadora 20mg with amex erectile dysfunction doctor in delhi, propranolol) to counter- act these effects buy tadora 20 mg with amex impotence at 18. Carbidopa may heighten this adverse effect, and there is no way to prevent it except by decreasing levodopa dosage. Many people prefer dyskinesia to lowering drug dosage and subsequent return of the parkinsonism symptoms. With amantadine, observe for: (1) CNS stimulation—insomnia, hyperexcitability, ataxia, Compared with other antiparkinson drugs, amantadine produces dizziness, slurred speech, mental confusion, hallucinations few adverse effects. It usually on the legs occurs with long-term use of amantadine and disappears when the drug is discontinued. With bromocriptine and pergolide, observe for: (1) Nausea These symptoms are usually mild and can be minimized by start- (2) Confusion and hallucinations ing with low doses and increasing the dose gradually until the de- sired effect is achieved. If adverse effects do occur, they usually (3) Hypotension disappear with a decrease in dosage. With pramipexole and ropinirole, observe for: These effects occurred more commonly than others during clinical (1) Nausea trials. With selegiline, observe for: (1) CNS effects—agitation, ataxia, bradykinesia, confusion, dizziness, dyskinesias, hallucinations, insomnia (2) Nausea, abdominal pain g. With entocapone and tolcapone, observe for: These effects occurred more commonly than others during clinical (1) Anorexia, nausea, vomiting, diarrhea, constipation trials. Drugs that increase effects of anticholinergic drugs: (1) Antihistamines, disopyramide (Norpace), thiothixene These drugs have anticholinergic properties and produce additive (Navane), phenothiazines, and tricyclic antidepressants anticholinergic effects. Drugs that decrease effects of anticholinergic drugs: (1) Cholinergic agents These drugs counteract the inhibition of gastrointestinal motility and tone, which is a side effect of anticholinergic drug therapy. Heart palpitations, headache, hypertensive crisis, and stroke may occur. Also, levodopa should not be started within 3 weeks after an MAO-A inhibitor is discontinued. Effects of MAO-A inhibitors persist for 1–3 weeks after their discontinuation. These effects are unlikely to occur with selegiline, an MAO-B in- hibitor, which more selectively inhibits the metabolism of dopamine. However, selectivity may be lost at doses higher than the recom- mended 10 mg/d. Drugs that decrease effects of levodopa: (1) Anticholinergics Although anticholinergics are often given with levodopa for in- creased antiparkinson effects, they also may decrease effects of levodopa by delaying gastric emptying. This causes more levo- dopa to be metabolized in the stomach and decreases the amount available for absorption from the intestine. Phenothiazines block dopamine receptors dol (Haldol), and thiothixene (Navane) in the basal ganglia. As a result, more levodopa is metabo- lized in peripheral tissues, and less reaches the CNS, where anti- parkinson effects occur. Drugs that decrease effects of dopaminergic antiparkinson drugs: (1) Antipsychotic drugs These drugs are dopamine antagonists and therefore inhibit the effects of dopamine agonists. What are the advantages and disadvantages of the various How Can You Avoid This Medication Error? Why is it desirable to delay the start of levodopa therapy of levodopa was given to Mr. When administering a combi- and, once started, reduce dosage as much as possible? What is the rationale for various combinations of anti- of carbidopa and 250 mg of levodopa. What are the major adverse effects of antiparkinson drugs, 100 mg that was ordered. Both Sinemet and tricyclic antidepressants have Drug facts and comparisons. Louis: Facts and anticholinergic side effects, including urinary retention and con- Comparisons. Describe nonpharmacologic interventions to which skeletal muscle relaxants are used. Critical Thinking Scenario John Moore was in an automobile accident 5 days ago, sustaining trauma to his back and shoulder.
If untreated cheap tadora 20mg with visa erectile dysfunction korean ginseng, giardiasis may Pneumocystosis is caused by Pneumocystis carinii tadora 20 mg free shipping erectile dysfunction naturopathic treatment, a para- resolve spontaneously or progress to a chronic disease with sitic organism once considered a protozoan but now con- anorexia, nausea, malaise, weight loss, and continued diarrhea sidered a fungus. Sources and routes of spread have not with large, foul-smelling, light-colored, fatty stools. It is apparently widespread in cies of vitamin B12 and fat-soluble vitamins may occur. Adults the environment, and most people are exposed at an early and children older than 8 years with symptomatic giardiasis age. Infections are mild or asymptomatic in immunocom- should be treated with oral metronidazole. However, the organism can form cysts in the lungs, persist for long periods, and become activated in im- munocompromised hosts. Groups at risk include parts of the world, especially in tropical regions. In the United human immunodeficiency syndrome (HIV) seropositive States, malaria is rare and affects travelers or immigrants from persons; those receiving corticosteroids or antineoplastics malarious areas. Plasmodium vivax, Plasmodium malariae, and Plasmodium ovale cause recurrent malaria by Toxoplasmosis forming reservoirs in the human host. In these types of malaria, signs and symptoms may occur months or years after Toxoplasmosis is caused by Toxoplasma gondii, a parasite the initial attack. Plasmodium falciparum causes the most life- spread by ingesting undercooked meat or other food contain- threatening type of malaria but does not form a reservoir. This ing encysted forms of the organism, by contact with feces from type of malaria may be cured and prevented from recurring. Once infected, the organism may persist in tis- opment occurs within the human body. However, symptoms rarely bites a person with malaria, it ingests blood that contains ga- occur unless the immune system is impaired or becomes im- metocytes (male and female forms of the protozoan parasite). When the mosquito bites cancer or organ transplantation), it is especially common and 616 SECTION 6 DRUGS USED TO TREAT INFECTIONS serious in people with AIDS, in whom it often causes en- SCABIES AND PEDICULOSIS cephalitis and death. Scabies is caused by the itch mite (Sarcoptes scabiei), which Trichomoniasis burrows into the skin and lays eggs that hatch in 4 to 8 days. The burrows may produce visible skin lesions, most often be- The most common form of trichomoniasis is a vaginal in- tween the ﬁngers and on the wrists. Antitrichomonal drugs Pediculosis capitis (head lice) is the most common type of may be administered systemically (ie, metronidazole) or ap- pediculosis in the United States. It is diagnosed by ﬁnding plied locally as douche solutions or vaginal creams. Pediculosis corporis (body lice) is diagnosed by ﬁnding lice HELMINTHIASIS in clothing, especially in seams. Pediculosis pubis (pubic or crab lice) Helminthiasis, or infestation with parasitic worms, is a com- is diagnosed by the presence of nits in the pubic and genital mon ﬁnding in many parts of the world. Occasionally, pubic lice may infest the axillae, mustache, often found in the gastrointestinal (GI) tract. Pediculosis may infect persons of any socio- eral types of parasitic worms penetrate body tissues or pro- economic status. Although scabies and pediculosis are caused duce larvae that migrate to the blood, lymph channels, lungs, by different parasites, the conditions have several common liver, and other body tissues. Most anthelmintics act locally to kill or cause occur in any geographic area and socioeconomic group. The goal of anthelmintic therapy effects (eg, clothing, combs and hairbrushes, bed linens). In BOX 41–1 HELMINTHIC INFECTIONS Hookworm infections are caused by Necator americanus, a Tapeworms attach themselves to the intestinal wall and may species found in the United States, and Ancylostoma duodenale, grow as long as several yards. Segments called proglottids, which a species found in Europe, the Middle East, and North Africa. Tapeworms are Hookworm is spread by ova-containing feces from infected peo- transmitted by ingestion of contaminated, raw, or improperly ple. Beef and ﬁsh tapeworm infections are burrow through the skin (eg, if the person walks on the soil with not usually considered serious illnesses. Pork tapeworm, which is bare feet), enter blood vessels, and migrate through the lungs to uncommon in the United States, is more serious because it pro- the pharynx, where they are swallowed.