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Biomedical subjects

R Recio

Publications and source records attributed to R Recio.

At least 19 recordsLinked to original sources
PubMed2004

Organophosphorous pesticide exposure alters sperm chromatin structure in Mexican agricultural workers.

Our objective was to evaluate alterations in sperm chromatin structure in men occupationally exposed to a mixture of organophosphorus pesticides (OP) because these alterations have been proposed to compromise male fertility and offspring development. Chromatin susceptibility to in situ acid-induced denaturation structure was assessed by the sperm chromatin structure assay (SCSA). Urinary levels of alkylphosphates (DAP) were used to assess exposure. Diethylthiophosphate (DETP) was the most frequent OP metabolite found in urine samples indicating that compounds derived from thiophosphoric acid were mainly used. Chromatin structure was altered in most samples. About 75% of semen samples were classified as having poor fertility potential (>30% of Percentage of DNA Fragmentation Index [DFI%]), whereas individuals without OP occupational exposure showed average DFI% values of 9.9%. Most parameters of conventional semen analysis were within normality except for the presence of immature cells (IGC) in which 82% of the samples were above reference values. There were significant direct associations between urinary DETP concentrations and mean DFI and SD-DFI but marginally (P = 0.079) with DFI%, after adjustment for potential confounders, including IGC. This suggests that OP exposure alters sperm chromatin condensation, which could be reflected in an increased number of cells with greater susceptibility to DNA denaturation. This study showed that human sperm chromatin is a sensitive target to OP exposure and may contribute to adverse reproductive outcomes. Further studies on the relevance of protein phosphorylation as a possible mechanism by which OP alter sperm chromatin are required.

Adolescent↗
PubMed2002

Effects of levonorgestrel implant upon TSH and LH levels in male infants during lactation.

OBJECTIVES: The objective of the study is to evaluate the effects of levonorgestrel transferred through breast milk on thyroid stimulating hormone (TSH) and luteinizing hormone (LH) levels in full breast-fed infants. METHODS: Forty healthy postpartum women and their male newborns were recruited for the study. Women were randomly allocated to two study groups: Group 1, IUD users and group 2, Norplant users. Blood and milk samples were collected on the day of IUD or Norplant insertion and 3 and 6 months later for TSH and levonorgestrel measurements. RESULTS: The results disclosed a significant decrease in TSH levels, and a negative relationship between LNG levels and TSH concentration in breast feeding infants at 3 months after implant insertion. The lowest TSH levels were observed at 6 months in the women from group 2. CONCLUSIONS: The overall data indicate that the LNG levels transferred to fully breast-fed infants through breast milk from Norplant users significantly modified their TSH levels.

Breast Feeding↗
PubMed2001

Organophosphorous pesticide exposure increases the frequency of sperm sex null aneuploidy.

It has been estimated that 4 of 1,000 live births and 35% of spontaneous abortions are aneuploid and that an important proportion of embryo and newborn aneuploidy is of paternal origin. Exposure to organophosphorous pesticides (OP) has been associated with sperm hyperploidy/polyploidy. Therefore, we aimed to assess the frequency of sperm aneuploidy (X, Y, and 18) and its relationship with urinary OP metabolites in agricultural workers. We performed multicolor fluorescence in situ hybridization on samples from nine men obtained before and during the pesticide spraying season to assess sperm aneuploidy. We measured urinary OP metabolite levels by gas-liquid chromatography. Aneuploidies were found in 0.67% of total sperm nuclei. The most frequent aneuploidy was the lack of a sexual chromosome or sex null (0.19%), followed by XY18 (0.15%) and XY18-18 (0.06%). OP metabolites detected at higher concentrations were dimethylthiophosphate, dimethyldithiophosphate, and diethylphosphate (DEP). There were no differences in average aneuploidy frequency or urinary metabolite levels between samples collected before and after exposure. However, Poisson regression analysis adjusted for age, alcohol intake, and sperm concentration showed significant associations between OP metabolite concentrations and increased frequency of sperm aneuploidies. The association was more evident between DEP and sex null, and the risk increased further during the spraying season. Thus, OP exposure could interfere with sperm chromosome segregation and increase the risk for genetic syndromes, such as Turner's. Further studies are required to assess the prevalence of spontaneous abortions, birth defects, and genetic syndromes in agricultural communities.

Abortion, Spontaneous↗
PubMed2001

Stress fracture of the femoral neck in a child. Case report and review of the literature.

Fatigue fractures generally appear in normal bone following increased repetitive activity or strenuous exercise, when imbalance occurs between applied force and elastic resistance. Femoral neck fatigue fractures are most common in athletes and young military recruits; such fractures in children with open physes are very rare. This paper reports a fatigue fracture of the femoral neck in an 8-year-old girl presenting with pain in the anterior aspect of the right thigh, of one month duration and without evidence of previous injury. Bed rest and relief of weight bearing are indicated for nondisplaced compression fractures. Surgical treatment is indicated for tension fractures. In most cases, the outcome is favorable, and complications are rarely reported.

Bed Rest↗
PubMed1997

Effects of oral buserelin on urinary LH secretion in male infants.

In recent years, several potent gonadotropin-releasing hormone (GnRH) analogues have become available for female contraception and one of them (buserelin) has been tested in lactating women. However, the possible effects on infants due to the transference of the analogue through breast milk have not been studied. The present work evaluated the effect of oral buserelin on urinary LH secretion in male infants. A total of 19 healthy full-term boys (aged 2-4 months) were included in the study. Infants received orally a single dose of a GnRH agonist mixed with breast milk. Urine samples were collected prior to, and 4-6 and 24 h after treatment for LH measurement. The results disclosed a significant increase in LH urine level in the sample taken 4-6 h after buserelin administration. Twenty-four hours after GnRH agonist ingestion, the LH level returned to baseline level. The present study demonstrated that GnRH analogue administered orally to infants escapes from gastrointestinal inactivation and induces a significant rise in LH levels 4-6 h after treatment.

Breast Feeding↗
PubMed1997

Effects of low steroid doses administered in the mid and late follicular phase on the LH surge, ovarian steroids and follicular maturation in eumenorrheic women.

The effects of four low doses of synthetic steroids, administered orally and starting on day 8 (group I) or on day 10 of the menstrual cycle (group II), upon LH surge, ovarian steroidogenesis, follicular maturation and menstrual cycles were studied in 10 eumenorrheic women. The results revealed that the day before the LH surge, the highest level of estrone-3-glucuronide was observed in both groups. Twenty-four hours after the last dose, the maximum urinary LH levels were recorded in groups I (day 11), and II (day 13). Pregnanediol-3 alpha glucuronide remained low during the study in group I, whereas in group II a gradual rise of this hormone starting on day 13 was registered and the highest level was found at day 21 of the menstrual cycle. Follicular maturation and ovulation were observed only in women from group II. Short and normal length cycles were recorded in groups I and II, respectively. In summary, low doses of exogenous synthetic steroids administered on day 8, but not on day 10 of the cycle, inhibit follicular maturation and ovulation.

Adult↗
PubMed1995

Effects of storage and temperature upon soft jelly capsules containing nonoxynol as spermicide.

Recently, adverse effects of long periods of storage and high temperature on physical characteristics of the soft jelly capsule wall were observed. In the present study, the effects of both parameters upon the mean rupture time of the capsule, and the release of the active compound were evaluated in vivo in 40 women. The results disclosed that the storage for long time and the exposure of the capsules to high temperatures, delays significantly the mean rupture time and the release of the active compound. A rapid distribution, adequate storage, as well as a delay of intercourse after vaginal insertion of the device are suggested.

Adult↗
PubMed1994

Safety and efficacy of a combined oral contraceptive: gestodene 75 micrograms plus ethinyl estradiol 30 micrograms in Mexican women.

An open prospective clinical trial designed to evaluate the efficacy and safety of the combined hormonal oral contraceptive (OC) containing 75 micrograms gestodene plus 30 micrograms ethinyl estradiol was undertaken in a Mexican population. Sixty-nine healthy women of reproductive age took part in the study for a total of 627 woman-months of observation. The combination of gestodene and ethinyl estradiol proved its effectiveness in preventing pregnancy during the study. Side-effects were minimal and regular endometrial bleeding patterns were observed during one year of continuous use of this OC preparation. The discontinuation rate for medical reasons was 11.6% at one year. Among a sample of 10 women, the gestodene/ethinyl estradiol combination did not induce significant changes in the serum concentration of total cholesterol and LDL cholesterol after 12 months of continuous administration. An increase in serum triglycerides and HDL cholesterol was observed; this effect could be attributed to a lack of androgenic and/or the intrinsic estrogenic behavior of gestodene. It can be concluded that this preparation is highly effective as a combined oral contraceptive; it is well tolerated and might offer some advantages with respect to other oral contraceptive combinations in its short- and medium-term impact on lipid metabolism.

Adult↗
PubMed1994

Gonadotropin-releasing hormone antagonist for postpartum contraception: outcome for the mother and male offspring in the marmoset.

GnRH antagonists have potential for use in postpartum contraception, as it is likely that they would be effective in maintaining the inhibition of ovulation associated with lactation, but possible effects on the infant by transfer of antagonist via breast milk are unknown. The aim of this study was to establish whether chronic treatment with a GnRH antagonist would prevent ovulation throughout the period of lactation using the marmoset monkey as a model and to evaluate the effects of the presence of GnRH antagonist in breast milk on the postnatal rise in plasma testosterone concentrations in male infants. Mothers who had delivered male twins were selected. Starting within 3 days postpartum, mothers (n = 5/group) were treated with either 6.0 or 0.6 mg/kg of the GnRH antagonist antide, sc, once per week for 11 weeks. Ten postpartum lactating females acted as controls. All animals were housed in family groups with fertile males. To determine possible effects on the postnatal rise in testosterone, plasma samples were collected from the male infants of the high dose antide-treated mothers at weekly intervals for 12 weeks. Plasma progesterone concentrations were monitored in lactating mothers until establishment of pregnancy in both treated and control groups. Concentrations of antide were determined by RIA in plasma from mothers in the high dose group, in their milk, and in pooled plasma samples from their infants. Ovulation followed by pregnancy occurred in all of the control animals. No ovulations occurred during treatment with antide. Antide was present throughout treatment in plasma and breast milk in the mother. In male infants feeding from mothers receiving high dose treatment, antide was not detectable in infant plasma, and plasma testosterone concentrations were within the normal range for male neonates in our colony. These results indicate that the GnRH antagonist has potential as a method of contraception postpartum without affecting the postnatal rise in testosterone in male infants.

Animals↗
PubMed1994

Blockade of the neonatal rise in testosterone by a gonadotrophin-releasing hormone antagonist: effects on timing of puberty and sexual behaviour in the male marmoset monkey.

In primates, plasma testosterone concentrations are elevated for some 3 months from birth. The function of this rise is uncertain, but studies in rats suggest that its prevention by castration or administration of gonadotrophin hormone-releasing hormone (GnRH) analogues has effects on development and expression of social and sexual behaviours, and adverse long-term effects on fertility. The consequences of suppression of this rise in testosterone by treatment with the GnRH antagonist antide have been investigated in the marmoset monkey. Eight sets of male:male twins were used, one of each set receiving s.c. injections of antide (10 mg/kg), on days 0, 3 and 7, then weekly from birth to 98 days of age, with the twin receiving vehicle only. Plasma samples were taken at weekly intervals for the determination of testosterone concentrations from birth until 2 years of age. Treatment with antide completely abolished the neonatal rise in testosterone seen in control animals. The timing of the onset of the pubertal testosterone rise was not significantly affected by treatment; however, the subsequent pattern of circulating testosterone showed a tendency to decreased plasma concentrations in the neonatally treated group from weeks 25 to 42, relative to controls, and this difference was significant between 43 and 70 weeks. This was associated with a similar depression in bioactive LH concentrations around this time. Thereafter, the testosterone concentrations were similar between treated and control groups. There was no effect of treatment on growth, based on sequential body weight data. At 20 months the animals underwent behaviour tests with ovariectomized females.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Assessment of a new modified soft jelly capsule containing nonoxynol as spermicide contraceptive.

The mean rupture time, after its vaginal insertion, of a new modified soft jelly capsule containing nonoxynol-9 (DF-486) was investigated in 40 women. The subjects were randomly allocated to 8 study groups. The capsules remained in the vagina from 2-13 minutes. Vaginal infection, vaginal dryness, and multiparity, were recorded. Capsule rupture was not observed at minute 2; 20% of capsules that remained in the vagina 3 minutes suffered rupture, as did 80% of capsules that remained 4, 5 and 7 minutes, and 100% of those remaining 9 minutes or more. The mean rupture time of the studied capsules was 8.2 minutes with 95% confidence limits of 6.2 and 8.8 minutes. At minutes 2-7, vaginal infection, dryness and tone diminution probably accounted for lack of rupture; after minute 7, these factors did not influence capsule rupture.

Administration, Intravaginal↗
PubMed1990

Immature spermatogenic cells and leucocytes in normal and abnormal semen.

The frequency and ranges of the immature germinal cells (IGC) were established in 286 semen analyses from normozoospermic (group I), oligozoospermic (group II), and azoospermic (group III) subjects. The mean total count of IGC was greater between men from group I than between participants from groups II and III. Scd spermatids were the cells most frequently observed and the spermatogonia the most unfrequently seen. Sab and Scd spermatids were the most common cells observed in group I, whereas Scd and primary spermatocytes were the most common in group II, and Scd and secondary spermatocytes were the most common in group III. Correlation was found between sperm concentration and the IGC total count. Significant differences were not found when epithelial cell and leucocyte concentrations were compared between groups.

Adolescent↗
PubMed1989

Estrogen-progestogen once-a-month injectable contraceptives and serum prolactin.

To assess the effect of hormonal monthly injectable contraceptives upon the serum values of immunoreactive prolactin (Prl), three groups of women of reproductive age exposed to different estrogen-progestogen injectable formulation for a minimum of one year were studied. The first group (n = 10) received dihydroxyprogesterone acetophenide 150 mg and estradiol enanthate 10 mg (DHPA/E2-EN), Group 2 (n = 21) received medroxyprogesterone acetate 25 mg and estradiol cypionate 5 mg (MPA/E2-C) and Group 3 (n = 19) was exposed to norethisterone enanthate 50 mg and estradiol valerate 5 mg (NET-EN/E2-V). A group of IUD users (n = 16) served as the control group. Serum Prl and 17 beta-estradiol (E2) concentration were determined in blood samples (0 and 15 min.) on days 0 (day of last injection), 10, 20 and 30 after last contraceptive injection. The results demonstrated a slight though not significant increase (p greater than 0.05) in serum Prl in the three experimental groups as compared with the IUD control group. This increase in Prl levels observed on day 10 post-last injection never exceeded the upper limits of the normal range (20 ng/ml). Overall, the data demonstrated that the chronic administration of these estrogen/progestogen once-a-month injectable contraceptives does not affect the Prl baseline secretion in women.

Adult↗
PubMed1989

Comparative trial between two soft jelly capsules containing nonoxynol as spermicidal contraceptives.

The rupture time of two types of soft jelly capsules (treated and non-treated) containing Nonoxynol-9 after its vaginal insertion was investigated in 96 women. Subjects were allocated in four study groups: Group I (n = 24), women with clinical vaginal infection; Group II (n = 24), subjects without vaginal infection; Group III (n = 24), patients with vaginal infection; and Group IV (n = 24), women without vaginal infection. Groups I and II received the treated capsules, and Groups III and IV the non-treated capsules. The capsules remained in the vagina for 2.5 to 5 minutes. The weight of the capsules was measured before insertion and after their extraction. Additionally, vaginal pH and distribution of the compound were assessed. The results disclosed that in Groups I, III and IV, the capsules ruptured within 2.5 minutes, whereas in Group II the rupture did not occur until 3 minutes. The largest number of non-ruptured capsules was observed in Group II. The major capsule weight loss occurred at minute 5 in most of the groups. The conditions currently observed in cases of non-ruptured capsules were: alkaline pH, multiparity and vaginal dryness. The vaginal distribution of the compound was observed at its upper portion. In women with vaginal infections, there were more cases of rupture and a significant weight loss between the treated capsules than the non-treated capsules. Further postcoital tests are required to assess its effectiveness.

Administration, Intravaginal↗
PubMed1988

Serum estrogens and ovulation return in chronic users of a once-a-month injectable contraceptive.

To determine whether the long-term exposure to a monthly injectable contraceptive, containing dihydroxyprogesterone acetophenide 150 mg and estradiol enanthate 10 mg, induces significant changes on the serum estrogens profile and ovulation return in women, a study in chronic users was undertaken. Ovarian function was assessed for 3 months following a single injection of the contraceptive agent in a group of women (n = 7) who have been on this formulation for an average period of 6.7 years and in a non-user control group (n = 7). The serum concentrations of 17 beta-estradiol, estrone and progesterone were measured in samples drawn at regular intervals throughout the entire study. The endometrial bleeding pattern was recorded in all subjects. The results indicated that the post-injection serum estradiol maximum levels (exogenous peak) occurred significantly earlier (p less than 0.05) in chronic users as compared with the non-user control group. Baseline serum estrone concentrations were slightly higher in chronic users than those observed in the control group, while the values of serum 17 beta-estradiol did not exhibit significant differences among the two groups. Ovulation was documented within 60-90 days after injection in all subjects from both groups. A similar length of the first bleeding-free period was observed in all participants. The overall data provide evidence of a moderate increase of estrone, one of the still active metabolic conversion products of 17 beta-estradiol, in the sera of chronic users of this combined contraceptive without affecting its pharmacodynamics.

Adult↗
PubMed1986

Pharmacodynamic assessment of dihydroxyprogesterone acetophenide plus estradiol enanthate as a monthly injectable contraceptive.

The pharmacodynamics of the combination of dihydroxyprogesterone acetophenide (DHPA) and estradiol enanthate (E2-EN) following its intramuscular administration at two doses were studied in 16 healthy women of reproductive age. Subjects were randomly allocated in two groups: group I (n = 9) received the combination DHPA 150 mg + E2-EN 10 mg on three consecutive monthly injections, while group II (n = 7) received half-dose of the same formulation. Ovarian function and endometrial bleeding patterns were investigated in all participants for one pre-treatment cycle, three treatment intervals and two post-treatment cycles. The results disclosed that ovulation was inhibited for at least 30 days following DHPA/E2-EN administration in all participants from both groups. The circulating estradiol levels 30 days after last injection were slightly elevated as compared with those observed in normal early follicular phase. Return to ovulatory cycles was documented within 90 days after treatment. The length of the bleeding-free intervals during treatment was shortened in both groups, particularly in group II. No significant changes in HDL-cholesterol levels were observed throughout the study. It is envisaged however, that large modification of the formulation and additional long-term safety studies will be required prior to its recommendation.

Adult↗