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Biomedical subjects

H Rui

Publications and source records attributed to H Rui.

81 records · Page 5Linked to original sources

Two-dimensional electrophoresis of proteins in various fractions of the human split ejaculate.

Two-dimensional electrophoresis of six fractions of split ejaculates from normal men (median age 23 years, n = 6) revealed large differences in the pattern of proteins found between the prostate-enriched fractions and secretions associated with the seminal vesicles. The glandular contributions were assessed using the concentrations of spermine, zinc and prostatic acid phosphatase (PAP) for prostatic secretion, and fructose and prostaglandin E for seminal vesicle secretion in the various fractions. Aside from PAP, four additional proteins were apparently associated with the prostatic fraction, one of which shared the biochemical characteristics of the specific ventral lobe protein of the rat prostate, prostatein (molecular mass 16 000, pI 4.8). The presumptive vesicular fractions contained a large number of low molecular mass proteins (10-20 000), with widely varying pI-values. The concentration of albumin and transferrin appeared to be highest in the sperm cell enriched fractions, indicating a major contribution to the ejaculate of testicular/epididymal origin.

Adult↗

Current approaches to research on prostatic function and pathology.

This article describes some of the techniques and approaches currently in use in prostatic research which hopefully will provide new information and perspectives on the etiology of prostatic pathology. These techniques include a variety of methods for visualizing and quantitating protein hormone receptors, protein electrophoresis of prostatic tissue and fluids for protein markers, cell separation of the different cell populations of the prostate so that their interaction can be evaluated, and tests for the influence of low molecular weight peptides on prostatic function. Examples of the type of information which can be derived from each of the approaches are included and discussed.

Adenylyl Cyclases↗

Accessory sex gland function in normal young (20-25 years) and middle-aged (50-55 years) men.

A comparison of various parameters of prostatic and vesicular secretory function was made between the seminal plasma of young (20-25 years; n = 23) and middle-aged (50-55 years; n = 19) male volunteers. These parameters included prostatic acid phosphatase, zinc, citric acid, spermine, spermidine, putrescine (prostatic origin), fructose, and prostaglandin E (vesicular origin), in addition to protein and testosterone. Spermatozoa were counted and monitored for abnormalities. The concentration in the ejaculate of the majority of the parameters investigated did not change with age, although the total contribution to the ejaculate from the prostate and seminal vesicles was reduced significantly in the older men. The concentration of three constituents was significantly altered in the older age group: putrescine (P less than 0.001) and prostaglandin E (P less than 0.01) were reduced, while zinc levels were elevated (P less than 0.05). These changes are discussed in relation to possible disturbances of prostate function and pathology in the middle-aged man.

Acid Phosphatase↗

Effects of oestrogen-induced hyperprolactinemia on the rat prostate.

Exposure of intact rats to increasing doses of oestradiol-17 beta in the presence of a constant amount of exogenous androgen caused a dose-related increase in the concentration of zinc in the lateral lobes and a decrease in the levels of ventral lobe prolactin binding. These changes occurred concomitantly with a dose-dependent increase in plasma prolactin levels, and could not be obtained in hypophysectomized rats given the same steroid treatment. In the intact animals a dose-dependent decrease in the responsiveness of the prostaglandin E1-dependent adenylyl cyclase in the ventral lobe was observed, an effect which has earlier been shown to be prolactin mediated. The results indicate that oestrogen has indirect effects on specific parameters of prostate function by inducing a relative hyperprolactinemia. This model may be useful in studying effects of chronically and physiologically elevated levels of endogenous prolactin on the rat prostate.

Adenylyl Cyclases↗

Androgen interaction with the polyamine system of the rat prostate.

The ventral and dorsal lobes of the rat prostate contain larger quantities of the aliphatic amines putrescine, spermidine and spermine and higher activities of the enzyme ornithine decarboxylase (ODC; EC 4.1.1.17) than other accessory sex glands. In contrast, the coagulating glands and the seminal vesicles contain only small quantities of the amines but the highest activities of the arginase (ARG; EC 3.5.3.1). Lineweaver-Burk plots indicated that the Km-values for ARG in the coagulating gland and ODC in the ventral prostate lobe were 20 mM and 0.2 mM, respectively. Castration decreased ODC and ARG activities to 3 and 50% of control levels, respectively, after 3 days, whilst the Km-values were unaffected. Daily administration of 3 mg dihydrotestosterone (DHT) prevented these castrational changes. Oestrogen treatment alone had no effect on the activities of the enzymes, but appeared to exert a synergistic effect with androgen on the ODC. Administration of androgen to intact rats for 7 days caused a dose-related alteration in the ratios of the various amines, particularly the spermine: putrescine ratio. A minor but significant decrease was also recorded in the activity of the ODC, which was mirrored by an increase in the levels of putrescine in the tissue. The data suggest that androgen control of the polyamine pathway is biphasic, first stimulatory and later inhibitory with lesions occurring at the ODC, possibly via short loop feedback of its product putrescine, but also at subsequent enzymic steps in spermidine and spermine biosynthesis.

Animals↗

Life styles of men in barren couples and their relationship to sperm quality.

This study is based on a questionnaire which focused on the possible association between life-style factors and male fertility in a group of 252 men attending our laboratory in connection with a fertility investigation. Their answers were correlated to sperm quality. No association could be documented between sperm quality and smoking habits, coffee drinking, a moderate alcohol intake, exposure to heat (sauna, hot baths, type of underwear, sedentary activities), or physical activities in their leisure time. In contrast, the reported average ejaculation frequency was significantly positively correlated to the motility of the sperm (% progressive), and inversely related to the proportion of sperm with abnormal morphology and semen volume. This indicates that the life style of the subject has little if any impact on semen quality, at least within the limits recorded in the present study.

Alcohol Drinking↗

Application of flow cytometry to studies on the human acrosome.

This study describes the use of flow cytometry combined with specific labelling of the human sperm acrosome using a FITC-labelled plant lectin (Arachis hypogea agglutinin). Localization of the label to the acrosome was encouraged by freezing the sperm for at least 24 hours at -70 degrees C prior to labelling. Studies of sperm from 53 normospermic men revealed that acrosome labelling followed a single normal distribution without the presence of subpopulations. The average fluorescence and degree of variation within the sperm population differed markedly between sperm samples. These differences could not be predicted by any of the normal criteria of sperm quality, including sperm morphology, vitality, and motility. Exposure of washed sperm to the calcium ionophore A 23187 in the presence of calcium at 37 degrees C, caused a time-related leftward shift in the distribution of acrosome fluorescence, indicating that this technique can be also used to monitor the acrosome reaction.

Acrosome↗

Sperm adenylyl cyclase in young and middle-aged men.

The present report is an extension of a previous study of the accessory sex gland function in normal young (20-25 years) and middle-aged (50-55 years) men. In the same individuals, the basal and in vitro stimulated activities of the sperm adenylyl cyclase were determined. A high degree of individual variation existed in both basal and Gpp(NH)p-, forskolin- and acetate-stimulated sperm adenylyl cyclase, and no significant difference could be demonstrated between the means of the age groups. Furthermore, no significant correlation existed between the concentrations of the glandular secretory products (prostatic acid phosphatase, citric acid, zinc, spermine, spermidine, putrescine, fructose and prostaglandin E) in the ejaculate and the activity of the sperm adenylyl cyclase. Furthermore, the number of morphologically abnormal sperm cells in the ejaculate did not influence the activity of the enzyme. No inverse correlation existed between the magnitude of basal activity and the relative response to Gpp(NH)p, forskolin or acetate suggesting that the variation in the enzyme could not be explained by its partial desensitization by seminal plasma constituents during the liquefaction period. A lack of correlation between the response of the enzyme to Gpp(NH) p and forskolin on the one hand and acetate on the other, implied that these drugs activate the enzyme through different mechanisms.

Acetates↗