scholarly journals Some aspects of the use of oral contraceptives as growth-promoting agents in poultry

2021 ◽  
Vol 1 (2) ◽  
pp. 241-247
Author(s):  
Ismail A. Sadek
Keyword(s):  
Electron Microscopy ◽  
Oral Contraceptive ◽  
Oral Contraceptives ◽  
Ultrastructural Level ◽  
Farm Animals ◽  
Anabolic Agent ◽  
Rate Of Growth ◽  
Cytoplasmic Organelles ◽  
Contraceptive Steroids ◽  
Growth Promoting

There are now several hormone and hormone-like agents that can improve the rate of growth and efficiency of feed use of farm animals. Feeding chickens with oral contraceptive steroids at the dose used by some poultry growers in Egypt has led to the formation of high estrogen residues in the muscles and the liver compared with controls. Electron microscopy of the livers of treated chickens revealed changes at the ultrastructural level. These alterations involve both the nucleus and cytoplasmic organelles, and are similar to those induced by 7, 12 dimethylbenz [a] anthracene in chickens. It is concluded that the use of oral contraceptive steroids in chickens as anabolic agent is a specific risk to chickens and probably to the consumer

Drug Interactions with Oral Contraceptives

1986 ◽  
Vol 20 (5) ◽  
pp. 353-362 ◽  
Author(s):  
P. F. D'Arcy
Keyword(s):  
Oral Contraceptive ◽  
Drug Interactions ◽  
Oral Contraceptives ◽  
Contraceptive Use ◽  
Enzyme Inhibitors ◽  
Enterohepatic Circulation ◽  
Oral Contraceptive Use ◽  
Contraceptive Steroids ◽  
Increased Risk ◽  
Contraceptive Activity

In the very rare cases where a pregnancy occurs during oral contraceptive use, the blame is usually laid against the patient for having forgotten to take the pill. Evidence has started to accumulate to suggest that neither the patient nor the pill is at fault in some contraceptive failures. It may be because the patient is taking other medicines and these may be preventing the pill from suppressing ovulation. Most drug interactions reducing or negating contraceptive activity are due to concomitant use of drugs having microsomal enzyme-inducing activity (e.g., some antibiotics, especially rifampicin, and anticonvulsants, including phenobarbital, Phenytoin, and primidone. Other antibiotics (e.g., tetracycline) may also interact by interruption of the enterohepatic circulation of contraceptive steroids. Less well appreciated, oral contraceptive steroids may themselves modify the metabolism and pharmacological activity of various other drugs (e.g., anticoagulants, benzodiazepines, β-blockers, caffeine, corticosteroids, and tricyclic antidepressants); in this respect the oral contraceptives are acting as enzyme inhibitors. Contraceptive steroids may also interact with drugs that cause enzyme inhibition and this delays the metabolism of the hormonal agents. Interactions of this type would be expected to potentiate the action of the contraceptive steroids. It is suggested that the effects of such interaction might be presented in terms of increased incidence of side effects, including water retention, diabetogenic effects, hypertension, and an increased risk of thromboembolic disorders. The spectrum of interactions with oral contraceptives is presented in three tables.

Permeability of Endometrial Blood Vessels to Exogenous Horse Radish Peroxidase in Mice. Electron Microscope Study

1973 ◽  
Vol 31 ◽  
pp. 562-563
Author(s):  
M.C. Castillo-Jessen ◽  
A. González-Angulo
Keyword(s):  
Electron Microscopy ◽  
Blood Vessels ◽  
Electron Microscope Study ◽  
Ultrastructural Level ◽  
Low Molecular Weight ◽  
Horse Radish Peroxidase ◽  
Intravascular Injection ◽  
Normal Morphology ◽  
Functional Implications ◽  
Low Molecular Weight Proteins

Information regarding the normal morphology of uterine blood vessels at ultrastructural level in mammals is scarce Electron microscopy studies dealing with endometrial vasculature despite the functional implications due to hormone priming are not available. Light microscopy observations with combined injection of dyes and microradiography along with histochemical studies does not enable us to know the detailed fine structure of the possible various types of blood vessels in this tissue. The present work has been designed to characterize the blood vessels of endometrium of mice as well as the behavior of the endothelium to injection of low molecular weight proteins during the normal estrous cycle in this animal. One hundred and forty female albino mice were sacrificed after intravascular injection of horse radish peroxidase (HRP) at 30 seconds, 5, 15, 30 and 60 minutes.

Immunocytochemistry. A Review of Methodology for Electron Microscopic Applicaiton

1974 ◽  
Vol 32 ◽  
pp. 328-329
Author(s):  
Joseph E. Mazurkiewicz
Keyword(s):  
Electron Microscopy ◽  
Light Microscopy ◽  
Ultrastructural Level ◽  
Electron Microscopic ◽  
Biological Interest ◽  
Investigative Approach ◽  
Immunologic Activity ◽  
Dense Label

Immunocytochemistry is a powerful investigative approach in which one of the most exacting examples of specificity, that of the reaction of an antibody with its antigen, isused to localize tissue and cell specific molecules in situ. Following the introduction of fluorescent labeled antibodies in T950, a large number of molecules of biological interest had been studied with light microscopy, especially antigens involved in the pathogenesis of some diseases. However, with advances in electron microscopy, newer methods were needed which could reveal these reactions at the ultrastructural level. An electron dense label that could be coupled to an antibody without the loss of immunologic activity was desired.

Erythrophagocytosis by Entamoeba histolytica.- Ultrastructural Study

1972 ◽  
Vol 30 ◽  
pp. 156-157 ◽  
Author(s):  
Norberto Treviño ◽  
Alfredo Feria-Velasco ◽  
I. Ruiz de Chávez
Keyword(s):  
Electron Microscopy ◽  
Light Microscopy ◽  
Entamoeba Histolytica ◽  
Ultrastructural Study ◽  
Saline Solution ◽  
Physiological Saline ◽  
Ultrastructural Level ◽  
Hot Plate ◽  
Physiological Saline Solution ◽  
Axenic Conditions

Although erythrophagocytosis by various species of Entamoeba is a well known phenomenon this has not yet been studied in detail at the ultrastructural level. The present work deals with the description of the incorporation process of erythrocytes by trophozoites of E. histolytica. For this study, trophozoites of E. histolytica, HK-9:NIH strain cultured in axenic conditions and washed human erythrocytes were placed on a hot plate at 37°C in physiological saline solution. After 5 minutes, 2.5% glutarldehyde was added and the samples were processed according to conventional techniques for electron microscopy.Based upon light microscopy studies on living trophozoites in contact with erythrocytes, it seems that erythrophagocytosis only takes place in one pole of the parasite.

Urinary melatonin, LH, oestradiol, progesterone excretion during the menstrual cycle or in women taking oral contraceptives

1987 ◽  
Vol 116 (1) ◽  
pp. 145-149 ◽  
Author(s):  
Jocelyne Brun ◽  
Bruno Claustrat ◽  
Michel David
Keyword(s):  
Oral Contraceptive ◽  
Menstrual Cycle ◽  
Urinary Excretion ◽  
Oral Contraceptives ◽  
Coefficient Of Variation ◽  
Luteal Phase ◽  
Positive Relationship ◽  
Follicular Phase ◽  
The Other ◽  
Normal Women

Abstract. Nocturnal urinary excretion of melatonin, LH, progesterone and oestradiol was measured by radioimmunoassay in nine normal women during a complete cycle. In addition, these hormonal excretions were studied in two women taking an oral contraceptive. A high within-subject coefficient of variation was observed for melatonin excretion in the two groups. In the nine normal cycling women, melatonin excretion was not decreased at the time of ovulation, but was significantly increased during the luteal phase compared with that of the follicular phase (P < 0.01). These data are consistent with a positive relationship between melatonin and progesterone during the luteal phase. In the two women under an oral contraceptive, melatonin excretion was found within the same range as for the other nine. The results are discussed in terms of pineal investigation in human.

scholarly journals The risk of breast, cervical, endometrial and ovarian cancer in oral contraceptive users

2010 ◽  
Vol 63 (9-10) ◽  
pp. 657-661 ◽  
Author(s):  
Milena Veljkovic ◽  
Slavimir Veljkovic
Keyword(s):  
Breast Cancer ◽  
Ovarian Cancer ◽  
Cervical Cancer ◽  
Oral Contraceptive ◽  
Oral Contraceptives ◽  
Young Women ◽  
Contraceptive Use ◽  
Epidemiologic Studies ◽  
Oral Contraceptive Use ◽  
Increased Risk

Introduction. Oral contraceptives, mainly combined monophasic pills, are widely used by young women who expect their physicians to prescribe them safe drugs which will not harm their health and which will simplify their life. Numerous epidemiologic studies have been performed to determine the relation between oral contraceptive use and the development of neoplasms. Breast cancer. An increased incidence of breast cancer has occurred simultaneously with the growing use of oral contraceptives. The possibility of a link between the oral contraceptive use and breast cancer has led to intensive research, but studies have provided inconsistent results causing confusion among clinicians. It was noticed that the risk of breast cancer was slightly elevated in current and recent young oral contraceptives users. That finding could be influenced by a detection bias or could be due to the biologic effect of the pills. The absolute number of additional breast cancer cases will be very small because of low baseline incidence of the disease in young women. Oral contraceptives probably promote growth of the already existing cancer, they are probably promoters not initiators of breast cancer. The available data do not provide a conclusive answer that is need. Cervical cancer. Numerous factors may influence the development of cervical cancer. The evidence suggests that current and recent oral contraceptive users have an increased risk of cervical cancer which decline after discontinuation of the application of medication. Oral contraceptives might increase the biological vulnerability of the cervix. Cervical cancer develops slowly over a long time period and can be effectively prevented by periodic cervical screening. Fortunately, oral contraceptives do not mask abnormal cervical citology. Conclusions regarding invasive cervical cancer and oral contraceptive use are not definitive but if there is any increased risk, it is low. Endometrial cancer. In oral contraceptive users the endometrium is almost under the influence of progestin component which suppresses endometrial mitotic activity and its proliferation. Most epidemiologic studies show that oral contraceptives reduce the risk of endometrial cancer and that this protective effect exists many years after the discontinuation of medication. Ovarian cancer. It has been long known that the oral contraceptive use causes protective an ovulation and reduces the risk of ovarian cancer. This powerful reduction is the best demonstrated major benefit of oral contraception. This protection is especially observed in nulliparous and seems to persist for many years after the discontinuation of medication.

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