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Biomedical subjects

F Vergara

Publications and source records attributed to F Vergara.

At least 19 recordsLinked to original sources
PubMed2005

External quality control program for semen analysis: Spanish experience.

PURPOSE: Results from an external quality control programme for semen analysis carried out in Spain are analysed. METHODS: Quality control materials were distributed and the following seminal parameters were determined: concentration, total motility, progressive motility, rapid progressive motility, morphology and sperm vitality. The between-laboratories coefficients of variation were assessed on different types of quality control material. RESULTS: The majority of participating laboratories utilised manual versus computer-assisted semen analysis methods. Some between-laboratories coefficients of variation ranges were: 20.8-33.8% for concentration (semen pool suspension); 13.9-19.2% for total motility (videotapes); 54.2-70.2% for sperm morphology (strict criteria using stained smears); and 9.8-41.1% for sperm vitality (stained smears). There was an inverse relation between mean percentage of sperm and coefficients of variation between laboratories for sperm motility, morphology and vitality. CONCLUSIONS: These data highlight the urgent need for improvement in the overall quality of andrology testing.

Clinical Laboratory Techniques↗
PubMed2003

Quantitative spectral analysis of EEG in psychiatry revisited: drawing signs out of numbers in a clinical setting.

OBJECTIVE: To evaluate the incidence, sensitivity and specificity of abnormal quantitative EEG (QEEG) measures in normal subjects and patients with mental disorders. METHODS: Normalized QEEG measures were blindly assessed in 67 normal human beings and 340 psychiatric patients. QEEG results were correlated to subject condition or diagnosis and magnetic resonance imaging (MRI) findings. RESULTS: QEEG was abnormal in 83% of patients, and 12% of normal subjects. The most frequent abnormality was a decrease in slow (delta and/or theta) bands, either alone, with beta increase, or with alpha decrease, followed by increase in beta band. No normal subject showed delta and/or theta decrease. Slow band decrease was more frequent in depression and mental disorders due to general medical condition, alcohol and drug dependence. However, no pattern was specific of any entity, and patients within the same diagnostic may present different patterns. Delta-theta decrease was correlated with cortical atrophy as seen in MRI. Beta increase was correlated with psychoactive medication. No association was found between any other QEEG pattern and MRI abnormalities, or medication. CONCLUSIONS: Decrease in the delta and theta bands of the QEEG can be regarded as a specific sign of brain dysfunction, and is correlated with cortical atrophy. However, this sign, as other QEEG abnormal patterns, can be found in many different disorders and none of them can be considered as pathognomonic of any specific disorder. SIGNIFICANCE: This work attempted to circumvent the alleged lack of Class I evidence of QEEG utility in the study of psychiatric patients by means of a prospective, blinded study, searching for specific signs of physiopathology in individual patients.

Adolescent↗
PubMed2003

Biological variation of seminal parameters in healthy subjects.

BACKGROUND: A study was undertaken to assess the components of biological variation of seminal parameters in healthy subjects. METHODS: Twenty donor candidates were included in a 10-week follow-up study. Within- and between-subject biological variation, indices of individuality and heterogeneity, coefficient of reliability, critical differences, analytical goals and the lowest value observed with a <5% probability of having a true value less than the World Health Organization (1999) reference value were estimated for the following seminal parameters: concentration, total motility (WHO grades a + b + c), progressive motility (grades a + b), rapid progressive motility (grade a), sperm morphology and vitality. All analysis was performed by a single technician according to WHO 1999 guidelines for routine semen analysis. Analytical variation was assessed on different types of quality control material (frozen straws, sperm suspension, videotape, and slides) and at different (low, medium, high) quality levels. RESULTS: The analytical variation observed depended on the quality control material used and the level of semen quality. Concentration was the semen parameter with highest within- and between-subject variation, and vitality the lowest. Indices of individuality were all <0.7, and coefficients of reliability were high (0.68-0.84). The critical difference for sequential values significant at P < 0.05 for vitality, progressive motility and morphology (34.4, 49.2 and 58.0% respectively) were lower than for concentration (77.8%). CONCLUSIONS: The study results showed that conventional reference values for seminal parameters have little diagnostic value because of their marked individuality, though seminal parameters can be useful for assessing differences in an individual's serial results, in particular of progressive motility, morphology and vitality.

Adult↗
PubMed2000

Lipid effects, effectiveness and acceptability of tibolone versus transdermic 17 beta-estradiol for hormonal replacement therapy in women with surgical menopause.

OBJECTIVE: To compare the effectiveness of tibolone and 17 beta-estradiol on climacteric symptoms, lipid and biochemical parameters in women with surgical menopause. METHODS: In a prospective randomised clinical trial group comparative study, the effects on the aforementioned parameters, as well as treatment compliance and side effects were studied with oral tibolone 2.5 mg per day and with transdermic 17 beta-estradiol at 50 microg per day for a period of 12 months. Statistical analysis was carried out using the Fisher-test, analysis of the variance (ANOVA) for the two factors and the Bouferoni test. RESULTS: Lipid metabolism analysis showed lower levels of HDL and triglycerides in the tibolone group. Other biochemical parameters were not affected. Similar reductions in climacteric symptoms were found in both the groups, but the tibolone group revealed a greater improvement in psychological problems and in sexual behaviour. No differences were observed with respect to compliance and side effects. CONCLUSIONS: Tibolone is as effective or more than 17 beta-estradiol in reducing climacteric symptoms, and shows greater triglyceride and total cholesterol improvements. Tibolone is a good alternative to estrogens in women with surgical menopause.

Administration, Cutaneous↗
PubMed1998

Increase of large granular lymphocytes in human ejaculate containing antisperm antibodies.

Using flow cytometry, we studied the expression of the CD16 antigen by lymphocytes present in human semen samples from three groups of patients: 60 fertile men attending for vasectomy, 60 sterile patients without antisperm antibodies (ASA) and 18 immunological sterile patients with ASA in their ejaculate. No significant difference was found in the concentration of leukocytes or subpopulations of these cells (monocytes, lymphocytes and granulocytes) between fertile, sterile without ASA and immunological sterile groups. However, we detected a predominance of macrophages/monocytes within the population of seminal leukocytes. No statistically significant difference was found in the absolute number of T and B lymphocytes between the three groups studied. However, a significant increase in the number of CD16+ lymphocytes was observed in the ejaculate of sterile patients with ASA as compared to the other groups. This finding might establish an important parameter in the follow-up and prognosis of patients with immunological sterility.

Adult↗
PubMed1995

CD4+ cells in human ejaculates.

Using flow cytometry, we studied the expression of the CD4 antigen within the different cells present in human ejaculate, both in spermatozoa and round cells. In all, 20 samples of semen were obtained from fertile males; in 11 of these, we detected the presence of leukocytes, using the peroxidase test. Swim-up was performed for the analysis of the spermatozoa. From our results it may be concluded that there is no expression of the CD4 antigen on the surface of human spermatozoa or on CD45- ejaculate cells (epithelial and germinal cells). However, we did detect the presence of the CD4 antigen on the surface of the leukocyte cells (CD45+). A better characterization of these CD45+ cells made it apparent that the CD4+ cells of ejaculate are composed of T lymphocytes (helper/inducer T lymphocytes) and monocytes. Thus we may conclude that human spermatozoa do not express the CD4 antigen, the cell surface receptor for human immunodeficiency virus. However, we did detect CD4+ T lymphocytes and CD4+ monocytes in semen.

CD4 Antigens↗
PubMed1995

Influence of incubation on the chromatin condensation and nuclear stability of human spermatozoa by flow cytometry.

Flow cytometry analysis was used for the accurate and objective evaluation of sperm chromatin condensation and chromatin stability of sperm nuclei. It was also possible to determine the influence of incubation on sperm chromatin. Different types of spermatozoa were studied: unprocessed spermatozoa at 1 and 45 min after ejaculation, after swim-up (migrated), spermatozoa incubated for 6 h in non-capacitating conditions (aged), or in B2 medium (capacitated) or B2 medium followed 1 h later with A23187 (reacted). All types of spermatozoa were analysed before and after treatment with various decondensation agents: sodium dodecyl sulphate (SDS), SDS plus EDTA and SDS plus disulphide-reducing agent [dithiotreitol (DTT)]. Sperm nuclei were enzymatically isolated and stained with propidium iodide. Three flow cytometric parameters were then measured: forward light scatter (cellular size), side light scatter (cellular complexity) and fluorescence (uptake of propidium iodide). Fluorescence was the most suitable parameter to study the degree of condensation and resistance to decondensation of DNA in the spermatozoa. Unprocessed spermatozoa 1 min after ejaculation underwent decondensation by all assessed treatments (anionic detergent, chelating or disulphide-reducing agents). Unprocessed spermatozoa 45 min after ejaculation and migrated spermatozoa did not undergo decondensation with SDS treatment, but decondensation occurred after treatment with SDS+EDTA or SDS+DTT. Spermatozoa incubated for 6 h under both non-capacitating (aged spermatozoa) and capacitating conditions (capacitated spermatozoa) and reacted spermatozoa were decondensed only after treatment with SDS+DTT.(ABSTRACT TRUNCATED AT 250 WORDS)

Calcimycin↗
PubMed1995

Undetectable expression of genomic progesterone receptor in human spermatozoa.

The expression of genomic progesterone receptor in human ejaculated spermatozoa was investigated. Spermatozoa from 10 fertile donors who exhibited normal semen parameters were analysed. Indirect immunofluorescence and an enzyme immunoassay using monoclonal antibodies against genomic progesterone receptor were used. Different types of spermatozoa were studied: fresh, post-swim-up (migrated), capacitated and post-artificial induction of the acrosome reaction by calcium ionophore A23187. Progestin receptor-rich T47D human breast cancer cells were used as a positive control, and progestin receptor-poor MDA-MB-231 human breast carcinoma cells were used as a negative control. Genomic progesterone receptor was not detected in fresh, migrated, capacitated and post-acrosome reaction induction human spermatozoa and MDA-MB-231 cells by either indirect immunofluorescence or enzyme immunoassay. However, in T47D cells a mean concentration of 1043.2 +/- 125.2 fmol genomic progesterone receptor/mg protein was observed by enzyme immunoassay, and indirect immunofluorescence results were positive using both flow cytometry and fluorescence microscopy. These findings suggest that the effect of progesterone on human spermatozoa is not mediated by genomic progesterone receptor.

Antibodies, Monoclonal↗
PubMed1994

Possible role of apamin-sensitive K+ channels in myotonic dystrophy.

Myotonic muscular dystrophy is a genetic disease characterized mainly by muscle atrophy and myotonia, a repetitive electrical activity of muscle. In the present study, the possible role of apamin-sensitive K+ channels in the genesis of myotonia was investigated. Apamin is a peptide from bee venom that specifically blocks small conductance Ca(2+)-activated K+ channels. The injection of a small amount of apamin (20-30 microliters, 10 mumol/L) into the thenar muscle of myotonic dystrophy patients decreased the basal electrical activity during the electromyogram in the 6 patients studied. Myotonic discharges after muscle percussion were more difficult to trigger and of smaller intensity and duration. In 2 controls and in 2 patients with generalized myotonia, as well as in 1 patient with myotonia congenita (where the defect is in chloride channels), apamin had no effect. These results suggest that apamin-sensitive K+ channels participate in the mechanism that generates myotonia in myotonic dystrophy.

Adult↗
PubMed1994

[Hypothyroid myopathy. Communication of 4 cases].

We report four patients with primary hypothyroidism (3 female, aged 47, 46, 49 and 34 years old) whose principal manifestation was muscle involvement. The diagnosis was oriented by the finding of myoedema and a slow relaxation phase of tendon reflexes. In one patient, an electromyographic and histological study was performed. Thyroid substitution lead to an improvement in myopathy in all patients.

Adult↗
PubMed1993

Efficacy of methylprednisolone administration in a case of continuous abnormal muscle activity syndrome.

We report a 20-year-old woman with continuous abnormal muscle activity syndrome in which pharmacological blockade of different sites of the motor unit demonstrates a peripheral nerve origin for the abnormal muscle activity. The case showed no markers of autoimmune disease. A rapid recovery after high dose i.v. methylprednisolone was observed supporting the hypothesis of an autoimmune pathogenesis.

Adult↗
PubMed1993

Lack of expression of HLA antigens on immature germ cells from ejaculates with antisperm antibodies.

PROBLEM: The lack of expression of HLA antigen on immature germ cells from ejaculates with antisperm antibodies has been reported. METHOD: The expression of human leukocyte antigens on immature germ cells from ejaculates with antisperm antibodies (ASA) was investigated by indirect immunofluorescence using a panel of monoclonal antibodies (MAb) and automated flow cytometry. Patients were divided into two groups: fertile (prevasectomic; N = 10), and ejaculates with ASA (10 samples with IgG and IgA ASA, and five semen samples with only IgG ASA). ASA were detected on sperm using the direct immunobead test. After centrifuging semen samples on a Ficoll-Hypaque gradient, round cells obtained at the gradient interface were gated by a flow cytometer. The "immature germ cell window" was defined in terms of cellular volume and granularity. RESULTS: The percentage of gated round cells from semen samples that reacted with anti-CD45 was always less than 5%, and with anti-CD44 less than 3%. This lack of reactivity of gated round cells with MAb specific for leukocytes and epithelial cells suggests that they were immature germ cells. Immature germ cells were unreactive with W6/32 and anti-beta-2-microglobulin MAb, which suggests that these cells do not express HLA class I molecules. Similarly, no reactivity of the immature germ cells with the MAb that recognize HLA class II molecules was found. No significant differences were observed in the expression of HLA molecules on immature germ cells between the different semen samples studied: fertile, and ejaculates with ASA. CONCLUSION: The presence of ASA in ejaculate is not associated with abnormal HLA antigen expression on immature germ cells.

Animals↗
PubMed1993

[Left heart catheterization by the transseptal route].

PURPOSE: To analyse the transseptal catheterization technique, its indications and possible complications. METHODS: The transseptal catheterization has been undertaken in 233 patients, 202 children (aged 0.1 to 16 years) with congenital heart disease and 31 adults (aged 37 to 73 years) submitted to mitral valvuloplasty. The Mullins technique was employed to access left heart chambers. RESULTS: In the pediatric group, the indications for transseptal catheterization were coarctation of the aorta and valvular or subvalvular aortic stenosis. By this technique, multiple diagnostic analysis and therapeutic procedures, such as blade atrioseptostomy and mitral valvuloplasty, became available. Among the complications in the 2 groups, pericardial perforation was the most frequent, depending on the laboratory practice with this technique. CONCLUSION: The transseptal cardiac catheterization is a safe and effective technique to investigate hemodynamic data in several congenital heart diseases and is essential to many therapeutic procedures. The technique has a low incidence of complications when employed by experienced teams.

Adolescent↗
PubMed1992

Adrenal hormones in human follicular fluid.

Considerable evidence indicates that adrenal hormones may affect gonadal function. To assess the role of some adrenal hormones in human follicular fluid and their relationship with the ability of the oocyte to be fertilized and then to cleave in vitro, cortisol and dehydroepiandrosterone sulfate were measured in follicular fluid obtained at the time of oocyte recovery for in vitro fertilization from cycles stimulated by clomiphene citrate, human menopausal gonadotropin and human chorionic gonadotropin. Thirty-six follicular fluid containing mature oocyte-corona-cumulus complexes and free of visible blood contamination were included in this study. There was no significant difference in follicular fluid dehydroepiandrosterone sulfate concentration between follicles with oocytes which did or did not fertilize (5.1 +/- 1.1 vs 5.8 +/- 2.0 mumol/l). However, follicular fluid from follicles whose oocytes were not fertilized had levels of cortisol significantly higher than those in follicular fluid from follicles containing successfully fertilized oocytes (406.0 +/- 75.9 vs 339.2 +/- 37.0 nmol/l; p < 0.005). No significant correlations were found between rates of embryo cleavage and cortisol and dehydroepiandrosterone levels in follicular fluid. We conclude that cortisol levels in follicular fluid may provide an index of fertilization outcome, at least in stimulated cycles by clomiphene citrate, human menopausal gonadotropin and human chorionic gonadotropin.

Adrenal Cortex Hormones↗
PubMed1992

Insulin and insulin-like growth factor I in follicular fluid after induction of ovulation in women undergoing in vitro fertilization.

This study was undertaken to evaluate the relationship between concentrations of insulin and insulin-like growth factor I (IGF-I) in follicular fluid and fertilization and cleavage of human oocytes fertilized in vitro. The concentration of oestradiol, progesterone, luteinizing hormone, follicle-stimulating hormone, testosterone, insulin and IGF-I was determined in 36 follicular fluids, free of visible blood contamination and containing mature oocyte-corona-cumulus complexes, obtained from 12 women undergoing in vitro fertilization. Follicular development was induced by clomiphene citrate and human menopausal gonadotrophin, and follicular aspiration was performed 35 h after an ovulatory dose of human chorionic gonadotrophin. Concentrations of IGF-I were significantly higher in follicular fluids associated with mature oocytes that fertilized and cleaved, than in follicular fluid associated with mature oocytes that did not fertilize (P < 0.001). There was no difference in the concentration of insulin between follicular fluids from which fertilized oocytes were obtained and those with oocytes that remained unfertilized. No significant correlations were found between rates of embryo cleavage, concentrations of insulin and IGF-I. Multiple linear regression analysis demonstrated that the concentrations of IGF-I in follicular fluid were predicted statistically by a negative regression coefficient for the concentration of testosterone, and by a positive regression coefficient for the concentration of progesterone in follicular fluid. No candidate variable was included in the model to predict concentrations of insulin. These data suggest an important role for IGF-I in the mature follicle.

Adult↗
PubMed1991

[Surgical treatment of uterine malformations].

Clinical data of 29 patients with uterine malformation treated at the Fertility Unit, Service and Department of Obstetrics and Gynecology, Dr. G. Grant B. Clinical Hospital, Concepción Chile from January 1978 to May 1990 are presented. Uterine septa (19 cases, 65.5%) were the most common uterine malformation found. Less frequent were: uterus bicornuous 7 cases (24.1%) and uterus didelphis 3 cases (10.4%). The high frequency (92.8%) of pregnancy wastage is detached. Surgical treatment was practiced in 24 patients. Thirteen Tompkins and 5 Jones techniques were performed in 18 uterine septa. Five Strassman techniques and one extirpation of a rudimentary not communicated horn were practised in the 6 cases with uterus bicornuous. In patients with adequate follow-up, the overall term birth rate after metroplasty is 84.6% compared with only 2.4% before surgical treatment. This study concludes that in despite of the lack of hysteroscopy as a new method of uterine septa treatment our patient's infertility was benefited with surgical treatment of uterine anomalies.

Abortion, Habitual↗
PubMed1991

[Anticardiolipin antibodies and primary antiphospholipid syndrome of the central nervous system: report of 10 clinical cases].

An association between anti-phospholipid antibodies and different disorders of the central nervous system has been described recently. We used an ELISA technique and detected anti-cardiolipin antibodies of the IgG or IgM variety in a series of 10 patients: 4 had occlusive stroke, 2 brain hemorrhage, 2 chorea, 1 a Sneddon syndrome and 1 vascular cephalea. The diagnosis of primary anti-phospholipid syndrome was suggested after ruling out systemic lupus in all patients.

Adult↗