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J C Hendrick

Publications and source records attributed to J C Hendrick.

At least 37 records · Page 2Linked to original sources
PubMed1986

Presence of alpha-lactalbumin, epidermal growth factor, epithelial membrane antigen, and gross cystic disease fluid protein (15,000 daltons) in breast cyst fluid.

The frequency of gross cystic breast disease in premenopausal women and its possible association with increased breast cancer risk emphasize the importance of investigations relating to breast cyst fluid composition. In order to contribute to a better analysis of this medium, we have measured four proteins the presence of which in human milk was well documented. Breast cyst fluid specimens from 266 breast cyst disease patients were assayed and compared as to concentrations of alpha-lactalbumin, gross cystic disease fluid protein (GCDFP-15), epidermal growth factor (EGF), and epithelial membrane antigen (EMA). All the analyzed cyst fluids contained GCDFP-15, EMA, and EGF whereas alpha-lactalbumin was detected in only 14.2% of fluids assayed. Positive correlations were observed between GCDFP-15 and EMA concentrations (P less than 0.005), as well as GCDFP-15 and EGF concentrations (P less than 0.0005). The cyst fluid GCDFP-15 and EGF levels were higher when alpha-lactalbumin concentrations were below detection limits. This association was statistically significant for GCDFP-15 (P less than 0.03) and for EGF (P less than 0.001). These results suggest that GCDFP-15 and EMA could be the biochemical expression of apocrine metaplasia and epithelial hyperplasia, respectively, two histopathological features which characterize breast cystic disease. On the other hand, the occasional presence of alpha-lactalbumin in the cyst fluid would reflect the persistence of differentiated cells in the epithelium surrounding the cyst and would be inversely proportional to the degree of cellular proliferation. The omnipresence of EGF in the cyst fluid argues for the hypothesis of its production by the mammary gland. The highly significant relationship between GCDFP-15 and EGF levels in the medium remains to be elucidated but may be related to an androgen sensitivity in the breast epithelium surrounding the cyst.

Apolipoproteins↗
PubMed1984

Effect of the presence of females on the pituitary-testicular activity in male Japanese quail (Coturnix coturnix japonica).

Five experiments were carried out to study the role of the presence of a female on the reproductive endocrinology of male Japanese quail. In the first three experiments, exposure of an adult male raised in long days to a female for l0 min or l week failed to increase plasma testosterone and LH levels; in fact a significant transitory decrease in plasma testosterone was observed, associated with a preceding increase in plasma corticosterone. These changes are interpreted as a result of the stress caused by repeated bleeding or by the continuous presence of a female in a limited space. In the last two experiments, an increase in the maturation rate of immature males could be observed in birds maintained in the continuous presence of females by comparison with birds kept in isolation. The paired males had larger cloacal glands and testes and higher plasma levels of testosterone and LH than the isolated one. This effect of the female was observed in long days (l6L:8D) as well as in marginally stimulating short days (l2L:l2D).

Animals↗
PubMed1984

Testosterone metabolism and testosterone-dependent characteristics in Japanese quail.

In 2 independent experiments, we measured and correlated in maturing male Japanese quail the individual variations in sexual and aggressive behavior, cloacal gland size, testes weight, plasma testosterone concentrations and intracellular testosterone metabolism by hypothalamus and cloacal gland. Cloacal gland area was only weakly related to plasma testosterone levels but was positively correlated with the production of active androgenic metabolites and negatively related to the production of 5 beta-reduced androgens (inactive) in the glandular tissue. Several measures of behavior were correlated with aspects of the testosterone metabolism in the anterior hypothalamus. In both experiments, the behavior of the birds was also strongly correlated with their testes weight and their cloacal gland area but weakly or not at all with their plasma testosterone levels. These studies suggest that testosterone metabolism is involved in the control of hormone action in maturing animals.

Animals↗
PubMed1984

[Products of exocrine secretion of the breast and breast cancer].

The breast is an exocrine gland which secretes the proteins present in breast milk, such as casein and lactalbumin. The apocrine metaplasia which often accompanies cystic transformation may result in the production of proteins in the cystic fluid: GCDFP (Gross cystic disease fluid protein). The production of these proteins by breast cancer and their secretion into the blood enable them to be considered as markers of tumour differentiation. They are useful to the clinical oncologist as quantifiable parameters of tumour extension and response to treatment. In the future, they may provide an index of malignant transformation and hormone dependence.

Apolipoproteins↗
PubMed1983

[Immunoenzyme assay of human cartilaginous proteoglycans and their antibodies].

An ELISA has been developed to measure human cartilaginous proteoglycans (PG) and their auto-antibodies. The assay is described step by step: successively the nature of the microtiter wells, the concentration of the PG to be coated, the optimal dilution of the antiserum, the length of various incubations and their respective temperature, are described. Standard curve obtained with purified PG is linear in a logit-log representation. The sensitivity of the assay is 2 ng/tube. Finally, biological fluids-sérum and synovial fluid-show a good parallelism with PG.

Autoantibodies↗
PubMed1982

[Tumor markers].

Several substances, referred to as tumor markers, are associated with neoplasms development. The specificity of these cancer related substances or antigens depends on their nature (onco-fetal antigens, placental antigens) or on their concentration and physico-chemical forms (hormones, exocrine products, enzymes,...). On the basis of physico-chemical, immunochemical and biochemical analogies which exist between these tumor markers and substances normally found at particular times of life, a classification of these markers may be proposed. Tumor markers are almost constantly found within carcinoma cells by immunocytochemical techniques and are secreted by carcinoma explants in culture medium. On the hand, the release of tumor markers in biological fluids (blood, cerebrospinal fluid, urines,...) is less frequently detected by sensitive methods such as radioimmunoassay. Several factors are responsible for this discrepancy between the intra-tumoral presence of tumor markers and the lower incidence of their detection in biological fluids. These factors are discussed. These tumor markers have attracted considerable attention from pathologists and clinicians. Thus, detection of these substances, especially by immunocytochemical methods, may be related to a situation of neoplastic transformation and allow a functional classification superimposed to histological classification superimposed to histological classification of tumors. Moreover, ectopic production of hormones and/or neuromediators explains some clinical symptoms in cancer processes. Furthermore, products of normal cell activity at the origin of cancer (hormones, enzymes, exocrine products) when evidenced within the neoplastic cells or within serum might constitute a hormonal dependence index useful for therapeutical orientation. Finally, tumor marker levels are related to the local and systemic extension of the neoplasia and may be considered as valid index of prognosis. The determination of the levels of these tumor markers provides a quantitative criterion of the evolution of the neoplastic disorder and for following the efficacy or inefficacy of treatment.

Adrenocorticotropic Hormone↗
PubMed1981

Participation of glucocorticoids in the regulation of plasma LH levels in the male domestic duck (Anas platyrhynchos L.).

Adult male domestic ducks were treated in autumn for 14 consecutive days with either (i) long-acting ACTH (20 IU/day), (ii) corticosterone (25 mg/day), (iii) dexamethasone (0.25 mg/day) or (iv) a control solution. Blood samples were obtained from all birds after 1, 3, 7 and 14 injections of hormones; on each of these occasions, a sample was obtained 3 times during the day. The 3 hormonal treatments induced a marked and transient (observed on the 3rd and 7th, but not on the 1st and 14th days of injection) elevation of the LH plasma levels. This increase was not associated with any alteration of the testosterone plasma levels. The results are discussed in view of our knowledge of the influence of adrenal hormones on the pituitary-gonadal axis.

Adrenocorticotropic Hormone↗
PubMed1980

Changes in pituitary responsiveness to luteinizing hormone-releasing hormone during an annual cycle in the domestic duck, Anas platyrhynchos L.

On four occasions during an annual cycle, 5--7 male domestic ducks were injected with two different doses (5 and 20 micrograms) of synthetic luteinizing hormone-releasing hormone (LHRH) to study the possible changes in responsiveness of the pituitary. The luteinizing hormone (LH) and the follicle-stimulating hormone (FSH) were measured in the plasma samples collected after these injections. The induced release of LH changes from one period of the year to another, being minimum in March at the height of the reproductive season. The LHRH injection also induces the release of some FSH but only in limited amounts. The changes in pituitary responsiveness to LHRH are negatively correlated to changes in the circulating LH level (it is high when the plasma LH is low and vice versa). This suggests that the hypothalamic synthesis and release of LHRH must also change during the year.

Animals↗
PubMed1979

Detection of virus antigens in Swiss albino mice infected by milk-borne mouse mammary tumour virus: the effect of age, sex and reproductive status. II. Radioimmunoassay of two virus components, gp47 and p28 in serum and organ extracts.

Extracts of various organs, mammary tumours and sera from milk-borne MMTV infected Swiss albino mice of different age, sex and physiological conditions were tested by radioimmunoassay for the presence of gp47, the main envelope polypeptide, and p28, the main core protein of the virus. Except in brain, ovaries and testes, both antigens were found in all organs of old animals and of females after the onset of their first pregnancy. Antigens were not present in organs of weanlings or in whole foetuses. Higher values were found in mammary glands, mammary tumours, epididymis and seminal vesicles. These organs also harboured a greater amount of gp47 than p28. The serum generally contained gp47 but rarely p28. This indicates that gp47 is not virion-bound in blood. Pregnancy, lactation and especially the presence of mammary tumours increased the concentration of gp47 in serum. The results do not allow localization of target organs of MMTV infection in the interval between ingestion of the virus by the suckling mouse and the first pregnancy. Moreover, results obtained with one group of mice devoid of exogenous virus show that, as endogenous MMTV genome expresses p28, it might account for part of the p28 detected exogenous MMTV-infected mice.

Aging↗
PubMed1979

Specificity of short-loop feedback of luteinizing hormone in the rabbit.

The specificity of the gonadotropin short-loop feedback mechanism was investigated in castrated rabbits by blood sampling from an indwelling jugular venous catheter for follicle-stimulating hormone (FSH) after the intravenous administration of purified human luteinizing hormone (hLH). Although we have previously shown that such hLH administration results in a decrease of rabbit LH, no decrease in rabbit FSH was seen in these experiments. This specificity of LH feedback is compatible with the site of feedback being at the (1) pituitary level or (2) at the hypothalamic level provided two separate LH and FSH releasing factors exist.

Animals↗
PubMed1979

Effects of exogenous gonadotropic and steroid hormones on the social behaviour and gonadal maturation of male domestic ducklings Anas platyrhynchos L.

Male domestic ducklings were injected during their first month of life with mammalian gonadotrophins (ovine LH or FSH, HMG) or gonadal steroids (testosterone or oestradiol). LH and testosterone stimulated sexual behaviour while oestradiol inhibited the increase of aggression observed in control birds during the experiment. The mammalian gonadotrophins did not increase plasma testosterone but nevertheless they all stimulated the testis growth. Several hypotheses which could explain this finding (stimulation of spermatogenesis without any apparent effect on testosterone) are discussed and the possibility of a direct action of LH on the sexual behaviour is analysed. Social displays were only moderately stimulated by testosterone and not at all by gonadotrophins. The hormonal controls of these behaviour patterns remains thus largely unknown.

Aggression↗