Determine Whether Vitamin A Enhances Immune Response

October 27th, 2008 by admin

Determine Whether Vitamin A Enhances Immune Response

Several approaches have been taken in an attempt to determine whether Vitamin A supplementation enhances immune response and resistance or recovery from infection. In some investigations, researchers have attempted to correlate plasma concentrations of beta-carotene or retinol with immune response or susceptibility to infection. One limitation of this approach is related to the fact that plasma concentrations may have depressed plasma retinol levels as a result of disease. Therefore, it is not possible to establish whether low plasma retinol levels resulted in suppressed immune response or if plasma retinol levels decreased in response to disease or infection. Another approach used is to supplement the diet with retinol precursors and examine immune response at a later time point. This approach may be useful in examining the particular aspects of immunity that may be altered by supplementation, but additional studies are necessary to determine whether these effects have clinical significance in terms of disease outcome. Vitamin A has been fairly well studied in terms of its immunomodulatory effects, and we will review the evidence from randomized controlled trials as well as potential mechanisms of action. Vitamin A supplementation may afford some protection from infection in malnourished individuals, but the potential benefits of supplementation in normal wellnourished individuals remain to be established. There is evidence from several studies that suggests that vitamin A deficiency is associated with depressed immune function and an impaired response to influenza infection. Supplementation of vitamin A is associated with a reduction of mortality and morbidity among certain populations. It appears that populations suffering from malnutrition may benefit from adequate or additional vitamin A supplementation. However, it is less clear if normal, healthy, well-nourished individuals will benefit from additional supplementation with respect to enhanced immunity. The results from several studies involving beta-carotene supplementation in the diet of healthy individuals suggest that certain aspects of innate immunity, such as NK cytotoxicity and monocyte production of the cytokine TNFcx, are enhanced. It appears that lymphocyte subsets or the lymphocyte response to mitogens are not altered. In addition, one study of healthy older individuals found that vitamin A supplementation was associated with a reduction in the number of T lymphocytes. Whether these observed changes of immune function in response to supplementation actually result in reduced susceptibility to infection in healthy individuals is not well established. The results from one study demonstrated no association between vitamin A supplementation and incidence of bacterial infection. we are not aware of any long-term, randomized clinical trials that have evaluated the incidence of viral infection in response to supplementation with vitamin A alone. However, several studies have examined the possibility that supplementation with several multivitamins and or trace elements such as zinc, may alter susceptibility to infection. In general, the findings from these studies show no protection from infection in association with vitamin intake, but a slight decrease in the incidence of infection in those individuals consuming supplemental trace elements such as zinc and selenium. At this time, the potential benefits of vitamin A supplementation for healthy well-nourished individuals regarding susceptibility to infection remain to be established. A high beta-carotene intake has also been associated with a reduced risk of cancer. Earlier epidemiological studies suggested a high natural (fruits and vegetables) intake of beta-carotene was associated with reduced risk of cancer. However, more recent studies have not observed any benefit of beta-carotene intake on incidence of cancer and two studies actually observed an increased incidence of lung cancer in those participants consuming beta-carotene supplements. The presence of other carotenoids in fruits and vegetables has been suggested to be the protective factor in regards to cancer incidence in the early epidemiological studies based on the findings from these recent studies, dietary supplementation with high doses of synthetic beta-carotene may be contraindicated for smokers. As a reminder, it has been known for some time that a high intake of vitamin A results in adverse effects (neurologic, dermatologic, musculoskeletal, gastrointestinal, birth defects) and the results from the most recent studies suggest a potential risk of high doses of synthetic beta-carotene in certain populations. At this time it is probably safest to follow the National Cancer Institute recommendations that suggest five or more servings of fruits and vegetables per day. Immune Effects and Exercise We are currently aware of only one study that has examined whether vitamin A supplementation is associated with a reduced incidence of infection in athletes. Several studies have shown that the risk of upper respiratory infection is increased following competition in marathons or ultramarathons However, vitamin A supplementation before marathon competition did not reduce the incidence of infection in the postrace period. Therefore, to our knowledge, vitamin A supplementation has not been associated with enhanced resistance to infection in healthy athletes.

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Treatment of cystic hydatid disease of the liver

October 18th, 2008 by admin

Albenza is indicated for the treatment of parenchymal neurocysticercosis due to active lesions caused by larval forms of the pork tapeworm. This medicine may also be used for the treatment of cystic hydatid disease of the liver, lung, and peritoneum, caused by the larval form of the dog tapeworm. Medication and treatment for dog tapeworm.
Albendazole is a white to off-white powder. It is soluble in dimethylsulfoxide, strong acids, and strong bases. It is slightly soluble in methanol, chloroform, ethyl acetate, and acetonitrile. Albendazole is practically insoluble in water. Each white to off-white, film-coated tablet contains 200 mg of albendazole.
Inactive ingredients consist of: carnauba wax, hypromellose, lactose monohydrate, magnesium stearate, microcrystalline cellulose, povidone, sodium lauryl sulfate, sodium saccharin, sodium starch glycolate, and starch.

CLINICAL PHARMACOLOGY
Pharmacokinetics: Absorption and Metabolism: Albendazole is poorly absorbed from the gastrointestinal tract due to its low aqueous solubility. Albendazole concentrations are negligible or undetectable in plasma as it is rapidly converted to the sulfoxide metabolite prior to reaching the systemic circulation. The systemic anthelmintic activity has been attributed to the primary metabolite, albendazole sulfoxide. Oral bioavailability appears to be enhanced when albendazole is coadministered with a fatty meal (estimated fat content 40 g) as evidenced by higher (up to 5-fold on average) plasma concentrations of albendazole sulfoxide as compared to the fasted state.
Maximal plasma concentrations of albendazole sulfoxide are typically achieved 2 to 5 hours after dosing and are on average 1.31 mcg/mL (range 0.46 to 1.58 mcg/mL) following oral doses of albendazole (400 mg) in 6 hydatid disease patients, when administered with a fatty meal. Plasma concentrations of albendazole sulfoxide increase in a dose-proportional manner over the therapeutic dose range following ingestion of a fatty meal (fat content 43.1 g). The mean apparent terminal elimination half-life of albendazole sulfoxide typically ranges from 8 to 12 hours in 25 normal subjects, as well as in 14 hydatid and 8 neurocysticercosis patients.
Following 4 weeks of treatment with albendazole (200 mg three times daily), 12 patientsÂ’ plasma concentrations of albendazole sulfoxide were approximately 20% lower than those observed during the first half of the treatment period, suggesting that albendazole may induce its own metabolism.

INDICATIONS AND USAGE
ALBENZA is indicated for the treatment of the following infections:

Neurocysticercosis: ALBENZA is indicated for the treatment of parenchymal neurocysticercosis due to active lesions caused by larval forms of the pork tapeworm, Taenia solium.
Lesions considered responsive to albendazole therapy appear as nonenhancing cysts with no surrounding edema on contrast-enhanced computerized tomography. Clinical studies in patients with lesions of this type demonstrate a 74% to 88% reduction in number of cysts; 40% to 70% of albendazole-treated patients showed resolution of all active cysts.

Hydatid Disease: ALBENZA is indicated for the treatment of cystic hydatid disease of the liver, lung, and peritoneum, caused by the larval form of the dog tapeworm, Echinococcus granulosus.
This indication is based on combined clinical studies which demonstrated non-infectious cyst contents in approximately 80-90% of patients given ALBENZA for 3 cycles of therapy of 28 days each (see DOSAGE AND ADMINISTRATION). Clinical cure (disappearance of cysts) was seen in approximately 30% of these patients, and improvement (reduction in cyst diameter of =25%) was seen in an additional 40%.
NOTE: When medically feasible, surgery is considered the treatment of choice for hydatid disease. When administering ALBENZA in the pre- or post-surgical setting, optimal killing of cyst contents is achieved when 3 courses of therapy have been given.
NOTE: The efficacy of albendazole in the therapy of alveolar hydatid disease caused by Echinococcus multilocularis has not been clearly demonstrated in clinical studies.

Treatment for dog tape worm ::

Online pharmacy Albenza Arranged by Viagracialislevitra

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