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Biomedical subjects

A Lucisano

Publications and source records attributed to A Lucisano.

At least 37 records · Page 2Linked to original sources

Distribution of the anthelmintic drug albendazole and its major metabolites in ovine milk and milk products after a single oral dose.

The distribution of albendazole (ABZ) and its main metabolites albendazole sulphoxide (ABZSO), albendazole sulphone (ABZSO2) and albendazole 2-aminosulphone (NH2ABZSO2) were investigated in bulk milk and milk products after administration of a single oral dose of the drug (12.5 mg/kg) to 80 Laticauda sheep. An analytical method was developed for this investigation from an existing procedure used for the determination of these compounds in plasma and digesta samples. No traces of the parent compound or NH2ABZSO2 were found in milk or milk products, with the exception of the milk collected 36 h after treatment in which 89 micrograms NH2ABZSO2/kg was detected. Results indicated that ABZ was rapidly oxidized to ABZSO and then to ABZSO2. These metabolites were found at high levels (1-4 mg/kg) in milk collected within 24 h after treatment. Products derived from such milk also contained high concentrations of the two oxidized metabolites, including up to 5 mg ABZSO/kg in Pecorino cheese. Only small quantities of these two metabolites were found in milk collected during the second day after treatment (range 50-500 micrograms/kg). They were no longer detectable in milk collected during the third day after dosing, nor were they found in products made from such milk. These findings confirm that the two polar metabolites ABZSO and ABZSO2 were efficiently excreted from the body. Considering that the established maximum residue limit for ovine milk is 100 micrograms/kg for ABZ plus its metabolites, our results confirmed the appropriateness of the currently prescribed withdrawal time (3 d) after the use of ABZ in lactating sheep. However, considerable levels of ABZSO were detected in milk collected within 24 h after treatment as well as in products and by-products derived from such milk. Owing to the known toxicity of the ABZSO, we stress the need for careful control to ensure adherence to the prescribed withdrawal time.

Albendazole↗

In vitro comparison of aldicarb oxidation in various food-producing animal species.

Aldicarb (ALD) metabolism was studied in vitro using hepatic microsomes from chickens, rabbits, sheep and pigs. The microsomal activities of mono-ooxygenase enzymes (flavin-containing and cytochrome P-450-dependent mixed function oxygenases) were compared by measuring the quantity of the 2 oxidized metabolites, ALD sulfoxide and ALD sulfone, produced during 60 min of incubation. Pig microsomes produced the greatest quantity of ALD sulfoxide and the lowest quantity of ALD sulfone; the latter being produced in greater quantities in sheep than in chickens and rabbits. Aldicarb and its metabolites were degraded fastest in rabbits, probably by hydrolytic reactions. These in vitro results, which are consistent both with the levels of cytochrome P450 found in hepatic microsomes and previous in vivo data on ALD kinetics in pigs, rabbits and chickens, indicate that preliminary in vitro studies can limit the necessary use of animals for drug metabolism experiments.

Aldicarb↗

Insulin, C-peptide, androgens, and beta-endorphin response to oral glucose in patients with polycystic ovary syndrome.

We examined the effects of an oral glucose load on plasma insulin, androgens, and beta-endorphin (beta EP) concentrations in patients carefully selected as having polycystic ovary syndrome (PCOS) and normal glucose tolerance. Our aim was to verify whether insulin resistance is a common feature of PCOS and to differentiate the metabolic abnormalities related to PCOS from those associated with obesity. Plasma immunoreactive insulin (IRI), C-peptide (C-PR), testosterone, androstenedione, dehydroepiandrosterone sulfate, ACTH, and beta EP responses to a 3-h oral glucose tolerance test (OGTT) were evaluated in 10 obese (OB-PCOS) and 10 nonobese (NO-PCOS) patients with PCOS and in 7 obese and 7 nonobese ovulatory controls. OB-PCOS and NO-PCOS did not differ significantly from weight-matched controls in the IRI response, but had a significantly higher C-PR response in terms of mean postglucose load levels and mean incremental areas. During OGTT, mean plasma levels of testosterone, androstenedione, and dehydroepiandrosterone sulfate declined in both PCOS groups as well as in controls, and no significant correlation between the plasma androgen and IRI or C-PR responses was found. The ACTH response in OB-PCOS and NO-PCOS was similar to that in controls, with a progressive decrease until 180 min. A similar decline in plasma beta EP was found in controls, whereas no change in plasma beta EP was observed in OB-PCOS and NO-PCOS. These findings indicate that independently of the presence of obesity, PCOS patients have enhanced insulin secretion in response to OGTT and show a peculiar pattern of changes in plasma beta EP.

Administration, Oral↗

The oxidative metabolism of aldicarb in pigs: in vivo-in vitro comparison.

Aldicarb was administered (1 mg/kg b.w.) to four female pigs and the kinetics of its major oxidized metabolites (sulfoxide and sulfone) was followed for 6 hours. The in vitro transformations of the carbamate pesticide into these two still active metabolites were also investigated in hepatocytes and in microsomes from pig livers. In all cases, aldicarb was quickly oxidized to the sulfoxide (major metabolite) and only a minor quantity of sulfone was produced. The in vivo toxic symptomatology was related to the peak serum concentration of sulfoxide, suggesting that this metabolite is principally responsible for the aldicarb toxicity. Selective in vitro inhibition of flavin-containing and cytochrome P-450 monooxygenases confirmed that the former enzymes catalyze mainly sulfoxide production whereas the latter that of sulfone.

Aldicarb↗

Chlamydial genital infections and laparoscopic findings in infertile women.

Several studies have shown that previous chlamydial genital infection, reflected by serological markers, is strongly associated with tubal damage leading to tubal infertility. In 105 women undergoing laparoscopy, multiple samples were collected from the lower (urethra and cervix) and upper (endometrium, peritoneal fluid, tubal lumen) genital tract, in order to isolate Chlamydia trachomatis in cell culture. Chlamydia trachomatis was isolated from at least one site in 13 (30.9%) of 42 infertile women with tubal infertility, in 5 (12.1%) of 41 women with unexplained infertility, in 1 of 4 women affected by acute salpingitis and in 1 (5.5%) of 18 women with endometriosis or uterine malformations. The latter group was the control group. Thirteen (65%) of the 20 positive women harboured Chlamydia trachomatis in their upper genital tract alone and 16 women were positive in one or both tubes. Only one of the positive women showed laparoscopic signs of acute pelvic infection. Four of the 5 positive women with unexplained infertility harboured Chlamydia trachomatis in the tubal lumen. This study confirms that chlamydial infection is strongly associated with tubal damage. It suggests that cervical cultures are inadequate for excluding a tubal infection and that chlamydial colonization of the tubal mucosa is possible in the absence of symptoms and laparoscopic signs of active infection.

Adult↗

Ultrasonic and endocrinologic aspects in gonadotropin releasing hormone induction of ovulation.

Ovarian growth, follicular size, 17 beta-estradiol (E2), androstenedione (A) and testosterone (T) peripheral levels were evaluated in 12 hypogonadotropic patients during the follicular phase on 12 cycles of pulsatile GnRH iv administration. During GnRH therapy, significant correlations between E2 plasma levels and volume of the dominant follicle (p less than 0.001) as well as total follicular volume (p less than 0.001) and total ovarian volume (p less than 0.01) were found. Plasma A was significantly related to the ultrasonic changes of ovarian stroma and those follicles which usually fail to ovulate. Plasma T showed a significant correlation with ovarian stroma (p less than 0.05). Significant correlations of E2/A and E2/T peripheral ratios with volume of the dominant follicle (p less than 0.01) were also found. In spontaneous ovulatory cycles, similar correlations between endocrine and morphological parameters have been already published. The findings of the present investigation indicate that in spontaneous and GnRH-induced cycles the endocrine events associated to the follicular development are quite similar. In hypogonadotropic patients, a "normal" follicular maturation may be obtained by means of this therapy.

Androstenedione↗

Salpingoscopy in patients with contralateral ectopic pregnancy.

Patients who experience a tubal pregnancy have a poor prognosis in terms of reproductive potential and are at increased risk of a repeat EP. Salpingoscopy is a new endoscopic technique that allows the detection of abnormalities of the tubal mucosa. In seven patients with a follow-up longer than 6 months, an IUP occurred only in patients with a normal ampullary mucosa, whereas a recurrent tubal pregnancy occurred in the patient that conceived with an abnormal tubal mucosa. These preliminary results suggest that salpingoscopy may constitute an important prognostic factor in these patients.

Adult↗

High prevalence of silent chlamydia colonization of the tubal mucosa in infertile women.

Thirty-four asymptomatic infertile patients without distal tubal occlusion were prospectively evaluated at laparoscopy for C. trachomatis infection. Samples were collected from the urethra, the cervical canal, the endometrium, the cul-de-sac peritoneal fluid and the endosalpinx. In 8 patients (24%), C. trachomatis was isolated from at least one site. In 6 patients C. trachomatis was isolated from at least one tube, demonstrating the possibility of silent chlamydial colonization of the tubal mucosa in the absence of signs of active pelvic infection.

Chlamydia Infections↗

[Partial deficiency in 21-hydroxylase in certain forms of hirsutism].

The ACTH test is important when hirsutism occurs in women with a slight 21-hydroxylase deficiency, and normal basal 17-OH Progesterone (17-OH-P/plasma levels). Extensive hormonal assays: LH, FSH, Prolactin, 17 beta-estradiol (E2), Estrone, 17OH-P, Androstenedione, Testosterone, Cortisol (C), Dehydroepiandrosterone-S (DEA-S) were carried out in 36 hirsute women. 13 of these presented hormone levels as found in polycystic ovary syndrome (PCOS), 6 women presented a slight 21-hydroxylase deficiency (increased plasma 17-OH-P and decreased C after ACTH test with significant, p less than 0.01, increase of 17-OH-P/C and 17 women presented idiopathic hirsutism (IH). The hormonal pattern, in the basal condition, is not different in IH or in slight 21-hydroxylase deficiency. The ACTH test is able to differentiate between IH and adrenal hirsutism.

17-alpha-Hydroxyprogesterone↗

Ovarian and peripheral androgen and oestrogen levels in post-menopausal women: correlations with ovarian histology.

Ovarian and peripheral plasma levels of oestrone (E1), oestradiol (E2), androstenedione (A) and testosterone (T) were assayed in 58 post-menopausal women who underwent hysterectomy and oophorectomy (35 for endometrial carcinoma and 23 for benign gynaecological diseases). No significant difference between the two groups was seen when they were matched for percentage of ideal weight. However, significant differences were found between the ovarian and peripheral levels of the four steroids investigated. To facilitate analysis of the data, 40 of these women were classified into three groups (1, 2 and 3) according to degree of stromal hyperplasia of the ovary. Group 1 comprised those with atrophic ovaries, group 2 those with slight stromal hyperplasia and group 3 those with moderate or marked stromal hyperplasia. Ovarian levels of A and T were significantly higher than peripheral levels in all three groups, but the ovarian/peripheral oestrogen differences were significant only in groups 1 and 2. The ovarian steroid levels in group 3 were significantly higher than those in groups 1 and 2 in the cases of E1 (P less than 0.01), E2 (P less than 0.001) and A (P less than 0.001), but not in that of T. It was concluded that ovaries showing marked stromal hyperplasia can produce significant amounts not only of androgens but also of E2, and hence that any evaluation of the hormonal pattern in post-menopausal women must also take into account the microscopic characteristics of the ovary.

Adenocarcinoma↗

Corpus luteum function during the early puerperium.

Progesterone and 17 beta-estradiol peripheral plasma levels have been determined during labor and after 1, 3, 6, 12, 24, 48, 72, 96, 120 and 144 h from delivery in a group of 7 women, whose corpus luteum had been removed at delivery and in a corresponding control group with intact corpus luteum. In both groups the results indicate a progressive fall of progesterone and 17 beta-estradiol, that is evident until 144 h for progesterone and 72 h from 17 beta-estradiol. The analysis of the two groups with the Student's t test has shown significantly lower levels in the group of women, whose corpus luteum had been removed, at the 6th h (p less than 0.01), 12th h (p less than 0.02) and 24th h (p less than 0.05) for progesterone and at 3rd h (p less than 0.01) and 6th (p less than 0.01) for 17 beta-estradiol. The significant difference for progesterone appearing later than for 17 beta-estradiol could be due to the fact that progesterone is also dismissed by the adipose tissue, where it is stored. A further statistical elaboration of the results, carried out by calculating the regression line and the transfer function, confirmed the different pattern in time of progesterone and 17 beta-estradiol plasma levels after delivery in the two groups of patients considered.

Adult↗

Amniotic membrane diffusion chambers: a new possibility for pancreatic islet transplantation.

In order to avoid the host foreign-body reaction which is probably responsible for the long-term failure of the artificial membrane diffusion chambers currently used for protecting the implanted islet tissue from rejection, we tested the human amniotic membrane as a possible new tool for enclosing transplanted islets of Langerhans. Bag-shaped chambers were made with human amniotic membranes and the diffusion of 125 I-Insulin out and of D-glucose into the chambers was measured. The diffusion patterns of insulin and glucose were shown to be better than those described for the best artificial membranes, the 50% diffusion being reached at min 42 for 125 I-Insulin and at min 11 for D-glucose. Moreover, it was shown that no lymphocytes diffused into the amniotic membrane chambers. These results, together with the already known characteristics of the human amniotic membrane, induce us to propose it as a suitable material for further experimental work in islet tissue transplantation.

Amnion↗

Ovarian and peripheral plasma levels of progestogens, androgens and oestrogens in post-menopausal women.

Ovarian and peripheral plasma concentrations of oestrone (E1), oestradiol (E2), androstenedione (A), testosterone (T), progesterone (P) and 17 alpha-hydroxy-progesterone (17 alpha OH-P) were assayed in 20 healthy post-menopausal women undergoing hysterectomy because of uterine fibromatosis. Significant differences were found between the ovarian and peripheral levels of E1 (P less than 0.01), E2 (P less than 0.001), A (P less than 0.01), T (P less than 0.001) and P (P less than 0.001). Analysis of the possible relationships between peripheral and ovarian levels of the six steroids considered and the patients' clinical characteristics revealed a positive correlation in only three cases, viz. between body weight and peripheral levels of E1 and E2, between E1 and E2 peripheral levels and between body weight and the E1/A ratio. The ovarian-peripheral gradient was calculated for each patient and was considered significant only if the ovarian peripheral difference exceeded the sum of each concentration multiplied by twice the maximal coefficient of variation of the assays used (12%). This gradient was significant in 75% of patients for T, in 45% for A, in 35% for E2, in 25% for E1, in 35% for P and in 30% for 17 17 alpha OH-P. Our findings confirm that circulating oestrogens in post-menopausal women originate mainly from the peripheral conversion of ovarian and adrenal androgens and that the ovary still continues to produce androgens. They also provide evidence that the ovary, at least in some post-menopausal subjects, can be a potential source of oestrogens and progestogens.

17-alpha-Hydroxyprogesterone↗

Evaluation of the feto-placental function by means of intraamniotic administration of dehydroepiandrosterone-sulphate.

It is well known that in pregnancy dehydroepiandrosterone-sulphate (DHEAS) (90% synthetized by the fetal adrenals, 10% by the maternal ones) is converted into estrogens mainly in the placenta. In order to evaluate the steroid metabolizing capacity of the placental enzymatic complex under load conditions, a test was devised based upon a rapid introduction of 200 mg of DHEAS into the amniotic compartment during the third trimester of gestation. The purpose of the present investigation was to establish the clinical utility of such a test in comparison with the simple urinary estrogen determination test.

Amnion↗

Perinatal fenvalerate exposure: behavioral and endocrinology changes in male rats.

The effects of maternal exposure to fenvalerate during the prenatal and postnatal periods of sexual brain differentiation were studied in adult male offspring. Behavioral (open field, stereotyped, and sexual behaviors), physical (sexual maturation, body and organ weights), endocrine (testosterone levels), and neurochemical (striatal and hypothalamic monoamine and respective metabolite levels) data were assessed. The results showed that there was no change in the age of testis descent or testis weight, nor were there changes in monoamine levels or stereotyped behavior. However, there were significant reductions in ductus deferens and seminal vesicle weights and plasma testosterone concentrations. In addition, treated offspring showed decreased male sexual behavior and increased immobility in the open field. These results indicate that perinatal exposure to fenvalerate during the critical periods of male brain sexual differentiation has long-term effects on the reproductive physiology and behavior of male rats.

Animals↗