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Biomedical subjects

A Rosado

Publications and source records attributed to A Rosado.

At least 91 records · Page 5Linked to original sources
PubMed1980

Species specific decondensation of human spermatozoa nuclei by heparin.

Decondensation of human spermatozoa nuclei has been induced by exposure of intact spermatozoa to heparin, while the spermatozoa of rabbit, ram, and bull remained highly condensed under similar experimental conditions. This process occurred in the complete absence of any disulfide bond cleaving reactant. Swelling of human spermatozoa nuclei commenced about 30 min after the addition of heparin and depended on heparin concentration reaching 83% of swelled nuclei after 6 hr. of incubation with 5000 USP of heparin per ml. Addition of 10 mg/ml of trypsin soybean inhibitor did not interfere with the swelling action of heparin. Electron microscope observations of human spermatozoa nuclei treated with heparin revealed that the chromatin is organized into "hublike" nuclear bodies joined by a network of cross-linked and branched chromatin fibers ranging in thickness from 25 to 1.5 nm.

Animals↗
PubMed1980

Changes in free aminoacid contents of erithrocytes and leukocytes during pregnancy.

Erythrocyte participation in the transfer and exchange of amino acids with tissues has been recently demonstrated. In this study, we show changes in erythrocytes, leukocytes and plasma free amino acid content, from peripheral blood in a group of 10 women after 25 weeks of gestation. Also tryptophan determinations in plasma and erythrocytes were made by fluorometric methods. During pregnancy, eleven of the 21 plasma amino acids studied are significantly different and the essential/nonessential ratio is not modified, although the total content diminished significantly. Conversely, in erythrocytes and leukocytes results indicate increase a in 2 and 3 fold respectively, in contents of aminoacid during gestation. The essential/nonessential ratio increases in the erythrocyte; In the essentials amino acids threonine, isoleucine and histidine show a greater increase. In leukocytes, the essential/nonessential ratio decreases during gestation due to a great increase of nonessentials, nevertheless, threonine, valine, methionine and leucine also show values significantly higher values during pregnancy. When amino acid content is calculated by mg of protein we see a certain increase in plasma, not significant, during pregnancy; in leukocytes, this increase corresponds almost to 90 per-cent with respect to the control group.

Adult↗
PubMed1980

Human fetal growth retardation. Metabolic response of leukocytes to phagocytosis.

The basal and stimulated metabolism of leukocytes obtained from fetally malnourished and normal children was comparatively studied. All basal activities of the leukocytes from malnourished children were significantly lower than those observed in normal children: Glucose-6-P-deydrogenase activity was 1.04 +/- 0.12 against 1.27 +/- 0.22 mumoles/min/10(8) cells; leukocyte-oxidase activity was 0.19 +/- 0.03 against 0.31 +/- 0.05 OD units/15 min/2.5 x 10(6) cells, oxygen uptake was 384 +/- 48 against 728 +/- 103 nmoles 0(2)/hr/10(8) cells. The conversion of glucose -1(14)C to 14CO2 was 83 +/- 10 nmoles/10(8) cells in malnourished children and 134 +/- 22 in controls. The response of all the parameters studied to the stimulation of phagocytosis was also significantly lower in fetally malnourished than in control babies.

Female↗
PubMed1979

Effect of prolactin on the calcium binding and/or transport of ejaculated and epididymal human spermatozoa.

The prolactin concentration in human seminal plasma and in human epididymal cauda fluid was assessed by radioimmunoassay. The prolactin concentration in cauda plasma was found to be similar to that found in male blood serum (5.5 to 9.1 ng/ml) and significantly lower than the concentration of the hormone found in seminal plasma obtained either from euspermic (48 +/- 12 ng/ml) or from vasectomized volunteers (50 +/- 10.2 ng/ml) (P less than 0.001). Calcium binding and/or transport in ejaculated spermatozoa were found to be little (0.29 +/- 0.08 nmoles/10(8) cells) and dependent on a quickly saturable process. The addition of 200 ng of human prolactin/ml induced a 60% increase in this parameter, while 50 ng of prolactin/ml were ineffective. Epididymal human spermatozoa differ from ejaculated sperm cells in showing greater, time-dependent, calcium binding and/or transport under basal conditions (2.00 +/- 0.35 nmoles/10(8) cells/hour), and in being more susceptible to the stimulating action of prolactin (4.4 +/- 0.68 nmoles/10(8) cells/hour in the presence of 50 ng of prolactin/ml).

Binding Sites↗
PubMed1979

Binding of 17-beta-estradiol to the outer surface and nucleus of human spermatozoa.

The binding of 3H-17-beta-estradiol to human ejaculated spermatozoa and to its subcellular structures was studied. The binding kinetics of the labeled steroid to whole spermatozoa followed a parabolic pattern. Scatchard-type plots showed the presence of high-affinity binding sites (1.56 +/- 0.23 X 10(4) per sperm cell) with an apparent Kd of 6.6 X 10(-10) M. In competition experiments testosterone was partially effective in decreasing 17-beta-estradiol binding, whereas progesterone and 17-alpha-estradiol were ineffective. Study of membrane fractions obtained from estradiol-labeled spermatozoa showed that under saturating conditions 75-84% of the bound steroid was bound to sperm membranes. Nuclear fractions obtained from estradiol-labeled spermatozoa showed only 10% of the total bound radioactivity. When isolated sperm nuclei were incubated in the presence of the purified receptor-17-beta-estradiol complex obtained from the high speed supernatant of human uterus almost no transfer of radioactivity to the nuclei was observed.

Binding, Competitive↗
PubMed1978

The human spermatozoa genome. Analysis by DNA reassociation kinetics.

The physicochemical characteristics of the human spermatozoa DNA have been analyzed by means of analytical ultracentrifugation and reassociation kinetics and compared with DNA from a somatic human cell, the leukocyte. Human spermatozoa DNA is composed of a major (86.7%) and a minor (13.3%) component with buoyant densities in neutral CsCl corresponding to 1.697 and 1.704 g/cm3, respectively. The DNA obtained from leukocytes contained only the first component. Reassociation kinetics of sheared DNA showed that the most rapidly-renatured repeated sequences consituted 12.1% of the sperm genome and only 9.2% of leukocyte genome. On the contrary single copy sequences were more abundant in leukocyte (64%) than in spermatozoa (59%) DNA. Reassociation kinetics with long DNA fragments (2000 nucleotides) were clearly different between sperm and leukocyte DNA, indicating the presence in sperm cells of a specific cluster of highly repetitive DNA. This entity may play a role in giving the spermatozoa nucleus its characteristic properties, involving supercoiling, quasi crystal structure, stability, lack of transcription, etc. and secondarily may function as an early pairing mechanism during syngamy.

Chromatin↗
PubMed1978

Calcium ion requirement for rabbit spermatozoal capacitation and enhancement of fertilizing ability by ionophore A23187 and cyclic adenosine 3':5'-monophosphate.

The presence of extracellular calcium is required for the in vitro occurrence of rabbit spermatozoal capacitation. However, calcium itself was found to be an inefficient agent for capacitating rabbit spermatozoa (following insemination with spermatozoa incubated for 10 hours in the presence of 2.5 X 10(-3) M calcium, only 9% of the ova cleaved). The addition of the divalent ionophore A23187 induced the early occurrence of capacitation and increased the percentage of full capacitated spermatozoa in a concentration-dependent manner (i.e, following insemination with spermatozoa incubated for 4 hours in the presence of 2.5 X 10(-3) M calcium and 2 X 10(-5) M A23187, 44% of the ova cleaved). Physiologic levels of capacitation were attained as estimated by the high proportion of ova that cleaved following in vitro insemination, when dibutyryl cyclic adenosine 3':5'-monophosphate (10(-6) m) was added in the presence of calcium (2.5 X 10(-3) M) and A23187 (2 X 10(-5) M) for treatment of spermatozoa.

Adenosine Monophosphate↗
PubMed1978

Metabolic changes induced in human spermatozoa by subagglutinating concentrations of specific antibodies.

The effects on sperm metabolism of subagglutinating concentrations of infertile female sera, containing antisperm antibody, were studied. Sera were selected by their differential agglutinating or immobilizing properties and by high titers of activity. Only the immobilizing antibodies were able to decrease sperm viability. Basal and succinate depending oxygen uptake, thus as progressive motility was decreased by sera producing mixed agglutination and more drastically by that producing immobilization independent of the presence of complement. The sera with head-to-head agglutination properties induced an increase in the above mentioned physiologic parameters. Tip of tail-to-tip of tail agglutinating sera having no effect on oxygen uptake were able to induce a significant increase in progressive motility. Conversion of 14C-Glucose to 14CO2 was decreased by sera that induced tip of tail-to-tip of tail agglutination and complement-independent immobilization. The sera which induced head-to=head agglutination and immobilization on the presence of complement, were without effect. None of the tested sera showed any acitivity over the conversion of 14C-Glucose to 14C-Lactate.

Antibodies↗
PubMed1978

[Post-natal growth of the child born with intra-uterine malnutrition].

Growth and morbidity were studied in a group of children at one and two years of age of which 10 were born with intrauterine malnutrition, 14 were prematures and nine had normal weight. All were evaluated , according to the Gesell test, at two years of age. Malnourished and premature children grew at greater rate than normals, reaching their size at one year of age. However, at the age of two, length of premature children was less than in normals. Gesell's test results were subnormal in 50 percent of the malnourished ones.

Age Factors↗
PubMed1978

[Changes in leucocyte metabolism during growth in children born with malnutrition].

Changes of energy metabolism in leucocytes have been studied longitudinally as well as cross-sectionally in three groups of children born: 1.- at term, with normal weight; 2.- with intra-uterine malnutrition; 3.- prematurely. The longitudinal study showed that, at birth, the activity of adenylate kinase as well as concentrations of ATP, ADP AND AMP were significantly lower in the malnourished than in the normal child. At one year of age, the values of enzyme activity are approximately equal in both groups, while the concentrations, of ATP and ADP are higher in malnourished children. Finally, at two years of age all values found, with the exception of AMP concentration, were higher in malnourished than in normal children born at term. In the data of the cross-sectional study this accelerated biochemical maturation is also shown.

Female↗
PubMed1977

Cyclic changes in salivary activity of N-acetyl-beta-d-glucosaminidase; a possible efficient indicator for predicting ovulation and pregnancy.

Salivary activity of N-acetyl-beta-D-glucosaminidase showed a characteristic pattern of changes during the normal menstrual cycle with a distinct peak on Day 13, 14, or 15 before the next menstruation. This peak of enzyme activity occurred withing one day of the nadir of basal body temperature and was absent in women with spontaneous or iatrogenic anovulatory cycles. These results are stongly suggestive that the salivary determination of this activity may be convenient indicatior for determining the day of ovulation.

Body Temperature↗
PubMed1977

Amino acid and protein concentrations of human follicular fluid.

The amino acid and protein composition of human follicular fluid, obtained during surgery from women with polycystic ovaries, and of a simultaneously obtained sample of blood plasma were studied. In general, amino acid concentrations were higher in follicular fluid than in blood plasma: only the concentration of Cys was significantly lower in follicular fluid than in plasma, while Asp, Thr, Glu, Glu-NH2, Gly, Ala, and Met showed concentrations that were not significantly different in either biologic fluid. The concentration of basic amino acids, taken as group, was almost twice as high in follicular fluid as in plasma. The total protein concentration in follicular fluid was not significantly different from that in blood plasma. However, the follicular fluid albumin concentration was higher and globulin concentration lower than the respective concentrations in plasma. Polyacrylamide gel disc electrophoresis of follicular fluid showed some consistent differences, particularly in the alpha-globulin region, with the pattern observed in blood plasma. These findings are discussed in relation to the possible role of follicular fluid in capacitation and egg segmentation.

Albumins↗
PubMed1977

Osmolality and conductance of normal and abnormal human seminal plasma.

The possible correlation between two important general properties of seminal plasma, osmolality and conductance, and the presence of some pathological conditions of human semen, asthenospermia and oligoasthenospermia, have been studied. Osmolality was measured under carefully controlled conditions by the freezing point depression method and conductance with a Wheatstone bridge. In addition, volume, by an isotopic dilution method, and pH were also determined. Osmolality of normal human seminal plasma (366 +/- 16 mOsm/Kg) was found to be higher than the osmolality of human blood serum. Abnormal seminal plasma showed a still higher value (428 +/- 38 and 457 +/- 49 mOsm/Kg respectively for astheno- and oligoasthenospermic subjects). Incubation of normal seminal plasma for 24 hours at room temperature produced a significant increase in osmolality (from 366 +/- 16 to 430 +/- 31 mOsm/Kg) while pathological seminal plasma failed to show any modification. Osmolality and conductance values were found to be correlated with semen ejaculated volume in normal subjects. No difference in mean conductance value was found between normal and asthenospermic individuals (10.4 +/- 1.2 against 9.9 +/- 1.0 mhos X 10(-3) respectively). Oligoasthenospermics showed, on the contrary, a significantly higher conductance (12.4 +/- 1.6 mhos X 10(-3)).

Adult↗