Hormones substitutes

Zitzmann M, Nieschlag E Hormone substitution in male hypogonadism. Mol Cell Endocrinol 2000 161 73. 

Wildemeersch D, Schacht E, Wildemeersch P. Performance and acceptability of intrauterine release of levonorgestrel with a miniature delivery system for hormonal substitution therapy, contraception and treatment in peri- and postmenopausal women. Maturitas 2003 44 237 15. 

Hormone substitution is sometimes referred to as simple replacement therapy. However, the use of exogenous hormones to replace normal endocrine function can be a complicated task. Problems such as regulation of optimal dosage, the interaction of the exogenous drug with other endogenous hormone systems, and drug-induced side effects are frequendy encountered. 

There is no LH preparation presently available for clinical use. Human chorionic gonadotropin— with an almost identical structure—is available and can be used as a luteinizing hormone substitute. 

In contrast to other protein-bound drugs for which a loading dose is given to achieve rapid steady-state concentrations, a slow and stepwise increase in thyroid hormone replacement therapy is advisable. This is preferred mainly to avoid sudden cardiac adverse effects, especially in older patients with long-standing myxedema. Moreover, since thyroid hormone substitution can change the metabolic clearance of this drug, steady-state concentrations are obtained only after several months (SEDA-6, 363). 

In efforts to modulate the biological availability profile by molecular manipulation, special attention has been paid to preparations with a sustained action, or depot preparations. The use of such depot preparations is most frequent in hormonal substitution therapy. However, depot preparations have also been developed for other types of drugs, usually on basis of conversion of the mother compounds by molecular manipulation to products with low water-solubility. 

The importance of a-fluoro-p-ketoesters stems from their use as synthons in the preparation of biologically active monofluorinated heterocycles(45) and fluorinated isoprenyl derivatives (46) which have found application as hyperlipidemic drugs (47), as hormone substitutes (48), and in cancer chemotherapy (49). 

Note-. Treatment of diffuse or nodular nontoxic goiter requires substitution of iodine either alone or in combination with levothyroxine, while treatment of hypothyroidism unrelated to iodine deficiency is achieved by a pure hormone substitution. 

The 30-year-old female client is prescribed chorionic gonadotrophin (Chorigon), a hormone substitute. Which intervention should the nurse implement ... 

Children with growth hormone deficiency produce only trihydroxy bile acids and have a low intestinal bile salt concentration (165). Growth hormone treatment restores these abnormalities and leads to improved intestinal absorption. A patient with acromegaly exhibited, after hypophysectomy with an adequate thyroid and adrenal hormone substitution, a markedly augmented bile acid synthesis (593 mg/day) which, however, was normal when related to the body weight (88). 

Treatment of placental insufficiency has been directed at improving the functional capacity of the placenta by means of hormonal substitution or by improving placental circulation. In many instances, however, the results have been unsatisfactory. We have therefore, considered the possibility of providing the fetus with nutrients independent of placental function. 

In X-linked adrenoleukodystrophy, the usefulness of bone marrow transplantation has been encouraging in clinically mildly affected patients with the childhood form of X-linked ALD. Adrenocortical insufficiency should be treated with steroid-hormone substitution. 

It has been proposed that thyroxine present in milk may play a role in providing some hormone substitution for newborns with congenital hypothyroidism. What is your opinion ... 

Other biomedical and biological appHcations of mictocapsules continue to be developed. For example, the encapsulation of enzymes continues to attract interest even though loss of enzyme activity due to harshness of the encapsulation protocols used has been a persistent problem (59). The use of mictocapsules in antibody hormone immunoassays has been reviewed (60). The encapsulation of hemoglobin as a ted blood substitute has received much attention because of AIDS and blood transfusions (61). 

Halogen-substituted succinimides are a class of products with important appHcations. /V-Bromosuccinimide [128-08-5] mp 176—177°C, is the most important product ia this group, and is prepared by addition of bromine to a cold aqueous solution of succinimide (110,111) or by reaction of succinimide with NaBr02 iu the presence of HBr (112). It is used as a bromination and oxidation agent ia the synthesis of cortisone and other hormones. By its use it is possible to obtain selective bromine substitution at methylene groups adjacent to double bonds without addition reactions to the double bond (113). 

Biochemistry is carbonyl chemistiy. Almost all metabolic pathways used by living organisms involve one or more of the four fundamental carbonvl-group reactions we ve seen in Chapters 19 through 23. The digestion and metabolic breakdown of all the major classes of food molecules—fats, carbohydrates, and proteins—take place by nucleophilic addition reactions, nucleophilic acyl substitutions, a substitutions, and carbonyl condensations. Similarly, hormones and other crucial biological molecules are built up from smaller precursors by these same carbonyl-group reactions. 

Estrogens and progestins are diminished in menopausal or ovarectomized women. In hormone replacement therapy (HRT), these hormones are substituted to alleviate hot flushes, mood changes, sleep disorders, and osteoporosis. 

Thus, this is a global phenomenon of fundamental importance for life on Earth many pesticides and/or their transformation products may substitute their activity for the hormonal system. Many earlier known examples of pesticide activity take on a dire new side in light of these views. Let us provide some illustrations ... 

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