Search PubMed⌕ Search

Biomedical subjects

S Marina

Publications and source records attributed to S Marina.

At least 19 recordsLinked to original sources
PubMed2003

The births of five Spanish babies from cryopreserved donated oocytes.

BACKGROUND: The technique of freezing oocytes is still not widely used. Reasons cited for this include the technique's low efficacy and the risk of aneuploidy. However, the introduction of technical changes (the type and concentration of cryoprotective substances; slow freezing and rapid thawing; and fertilization by ICSI) has led to improved results. We present four pregnancies obtained using mature oocytes (in metaphase II) that had been frozen and thawed. The oocytes were donated by young women who were not patients. METHODS: The frozen oocytes (n = 88) came from seven donors aged 18-25 years. The metaphase II oocytes, morphologically normal in appearance, were denuded of their cumulus-corona complex. The cryoprotective freezing solution contained 1,2-propanediol (1.5 mol/l) and sucrose (0.3 mol/l). Freezing was slow and thawing rapid. The oocytes were fertilized by ICSI. RESULTS: Seventy-nine of the 88 thawed oocytes survived (89.8%); 58 were fertilized (73.4% of all those microinjected); and 26 were transferred (44.8% of all those fertilized). Four pregnancies were produced after seven transfers (57.1%). Five children were born from four pregnancies. CONCLUSIONS: With the freezing/thawing technique used, oocyte survival was high ( approximately 90%). The pregnancy rate with frozen oocytes was similar to that obtained using fresh oocytes from donors ( approximately 50%).

Adult↗
PubMed2000

The decision to cancel a preimplantation genetic diagnosis cycle.

It has been suggested that a minimum number (six) of cumulus-oocyte complexes (COCs) should be retrieved for fertilization to offer enough chances to ensure a pregnancy after a preimplantation genetic diagnosis (PGD) procedure. Therefore a decision to cancel a PGD cycle should be adequately weighted to offer the patients the highest chances to obtain a pregnancy. We describe a case where, after retrieving only three COCs suitable for fertilization, a triplet pregnancy was obtained. This case suggests that, although low numbers of COCs can reduce the effectiveness of the PGD procedure, other factors are involved in its final result. Thus, the opportunity of routinely cancelling such cycles should be reconsidered. In addition, this is, to our knowledge, the first case where sex selection was carried out to prevent the birth of carriers of the abnormal gene, and not of affected offspring.

Adult↗
PubMed1999

Oocyte donor selection from 554 candidates.

Oocyte donation is a technique in full expansion in the field of human reproduction. The main problem with this technique is the shortage of oocytes. In our programme, prospective donors are selected from anonymous, well-informed university students over 18 years of age, who give their informed consent in writing. Before being accepted as donors, the candidates' personal and family medical histories were taken and they were given a gynaecological examination, genital ultrasonography, and analysed for syphilis, acquired immune deficiency syndrome, hepatitis B and C, coagulation factor VIII, fetal haemoglobin and karyotype. The donors received economic compensation of about 750 euros. Over the last 6 years, 554 medical histories have been taken. Fifty-eight candidates (10.5%) were rejected because of previous family or personal pathologies. Only 243 out of 496 (49%) continued the study. Sixteen candidates (7%) were rejected as a result of gynaecological problems and ultrasonographic results; and 12 (4.9%) as a result of their blood test results; 215 donors were accepted (38.8% of the original population). Other options for recruiting oocyte donors are commented on and we argue that the methodology described here is the most suitable one.

Adult↗
PubMed1999

Triplet pregnancy achieved through intracytoplasmic sperm injection with spermatozoa obtained by prostatic massage of a paraplegic patient: case report.

Spinal cord-injured men with ejaculation disorders can have children thanks to assisted reproduction techniques. Spermatozoa from these patients are usually obtained through vibratory stimulation, electroejaculation or by puncturing the seminal duct or the testicle. We present the first published case, as far as we are aware, of spermatozoa obtained through prostatic massage of a paraplegic patient. Penile vibratory stimulation was unsuccessful in this patient. In-vitro fertilization (IVF) with intracytoplasmic sperm injection (ICSI) with spermatozoa obtained through electroejaculation was performed at another centre but pregnancy was not achieved. Through prostatic massage, we obtained a total semen volume of 6 ml containing a total count of 12.32x10(6) spermatozoa (6.24x10(6) with tails), 8% of which had motility (graded + and ++); and 16% of which had normal morphology. The spermatozoa obtained were then used to perform IVF with ICSI and a triplet pregnancy was achieved. Prostatic massage appears to be an easy, non-traumatic and risk-free method to obtain spermatozoa from paraplegic patients.

Adult↗
PubMed1998

Human immunodeficiency virus type 1--serodiscordant couples can bear healthy children after undergoing intrauterine insemination.

OBJECTIVE: To use semen from men who were seropositive for human immunodeficiency virus type 1 (HIV-1) to inseminate their partners without infecting them. DESIGN: Prospective study. SETTING: Private practice. PATIENT(S): Sixty-three HIV-1-seropositive men and their HIV-1-seronegative female partners. INTERVENTION(S): The men provided 107 semen samples that were prepared with the use of the Percoll and swim-up techniques. The presence of HIV-1 was determined in the fraction of motile spermatozoa obtained after washing. If HIV-1 was not detected. IUI was performed in stimulated cycles. MAIN OUTCOME MEASURE(S): Human immunodeficiency virus type 1 RNA and DNA were detected with the use of the polymerase chain reaction technique modified for spermatozoa. RESULT(S): One hundred seven semen samples were washed. Human immunodeficiency virus type 1 was not detected in 101 samples (94.4%) and was detected in 6 samples (5.6%). In the latter cases, IUI was not performed. One hundred one IUI procedures were performed in 63 women. Thirty-one pregnancies resulted, for a pregnancy rate of 30.7% per cycle and 49.2% per inseminated woman. Thirty-seven healthy children were born. The results of tests for the detection of HIV-1 and antibodies to HIV-1 in the inseminated women were negative. CONCLUSION(S): On the basis of these results, testing for HIV-1 with the use of the polymerase chain reaction technique on the semen fraction obtained after washing appears to prevent infection in the inseminated woman. This method makes it possible to help HIV-1-seropositive men to have children without infecting their female partners.

Adult↗
PubMed1998

Pregnancy following intracytoplasmic sperm injection from an HIV-1-seropositive man.

The first pregnancy achieved in a seronegative woman following in-vitro fecundation through intracytoplasmic sperm (ICSI) injection from a man with autoimmune deficiency syndrome (AIDS; HIV-1 carrier) is reported. The semen was prepared by PureSperm and swim-up techniques. Some of the motile spermatozoa obtained were used to detect the presence of HIV-1 using the polymerase chain reaction technique. HIV-1 in DNA or RNA form was not detected using this technique. The remaining spermatozoa were frozen. Ovarian stimulation in the woman was performed with long-protocol analogues and gonadotrophins. Thirteen mature oocytes were recovered, into which the thawed spermatozoa were microinjected. Nine embryos were obtained. Four were frozen, four transferred and one discarded. The woman became pregnant. Analyses for HIV-1 in the woman, performed in the first and third months of pregnancy, gave negative results. This case provides further experience with washed semen of sufficient quality for performing artificial insemination in HIV-1-serodiscordant couples (101 inseminations, 31 pregnancies, 28 deliveries, 37 babies, all healthy). In women with obstructed Fallopian tubes, or when the semen is not of sufficient quality for artificial insemination techniques to be performed, ICSI can be carried out using frozen, HIV-1-free semen.

Acquired Immunodeficiency Syndrome↗
PubMed1994

Quantitative characterization of the frequency and location of cell proliferation and death in prostate pathology.

This paper evaluates the use of quantitative methods to accurately assess cell proliferation and death in untreated and treated prostate lesions. The analysis of proliferating cell nuclear antigen (PCNA)-stained nuclei allow precise evaluation of the proliferating cells and exact identification of their location in the progression of untreated prostatic intraepithelial neoplasia (PIN) to prostatic adenocarcinoma (PAC). The evaluation of the frequency and location of apoptotic bodies (ABs) gives accurate information on the apoptotic phenomenon in PIN compared to normal prostate (NP) and PAC. In fact, the frequency of ABs increases from NP to PIN to PAC and parallels that observed with PCNA. However, the AB-related values were approximately one-eighth to one-tenth of those obtained with PCNA immunostaining. Combination endocrine therapy (CET) decreases the proliferative activity and enhances the apoptosis phenomenon in NP, PIN, and PAC. This might indicate that CET could induce a certain degree of regression not only of PAC, but also of PIN.

Adenocarcinoma↗
PubMed1991

XY-trivalent association and synaptic anomalies in a male carrier of a Robertsonian t(13;14) translocation.

Synaptonemal complexes were analysed in 91 pachytenes from a patient carrier of a Robertsonian translocation 45XY, t(13;14). Electron microscopic studies were carried out in 36 pachytenes. In some cases, sequential light microscopy/electron microscopic images were obtained (16/36). As the resolution of the light microscope does not allow an accurate characterization of anomalies, only EM images have been taken into account. Association of the trivalent and the sex vesicle was detected in 8 of 36 pachytenes (22.2%). Synaptic anomalies (25%), fragmentation of synaptonemal complexes (11.1%) or both (2.8%) were seen in 14 of 36 nuclei. According to previous studies, synaptic anomalies may produce a spermatogenic arrest. However, it has been suggested that synaptic anomalies may be the result of a process of cell degeneration, and not its cause. The non-random relationship between the sex vesicle and the translocation trivalent may result from the tendency of unpaired segments to associate with each other after homology search is relaxed and heterologous synaptic adjustment is allowed.

Adult↗
PubMed1990

Karyotype screening of potential sperm donors for artificial insemination.

Cytogenetic studies were carried out in 100 potential semen donors for artificial insemination (AI) before they underwent the routine procedures for acceptance or rejection into the programme, namely medical history, physical examination and blood and semen analyses. Results were only compared at the end of the study. In 80 cases, the karyotype was normal; 12 males showed polymorphic chromosome variants; seven had pericentric inversions of heterochromatic regions; one had a short inversion of chromosome 2; and in one case centromere fragility was observed. Six of the 12 males with normal variants were accepted into the programme and four of them had fathered from one to 13 normal children at the end of the study; the other six had been rejected, four of them because of abnormal seminograms, and another two because the motility control of the frozen semen was negative. Of the seven males with pericentric inversions, one dropped out of the programme; four were accepted and three of them had produced from two to five normal children at the end of the study; two had been rejected due to abnormal seminograms. The individual with centromere fragility was accepted and had produced four normal children at the end of the series. Our conclusion is that although cytogenetic studies of potential donors for AI would be desirable, routine screening for chromosome anomalies is not justified at present.

Genetic Testing↗
PubMed1990

[Xanthogranuloma juvenile combined with neurofibromatosis].

Xanthogranuloma juvenile is a rare condition of childhood. The disease typically begins in infancy or early childhood and despite the number of papules, eventuates in cure in two to five years. The present report describes an extremely rare combination of xanthogranuloma juvenile with neurofibromatosis.

Biopsy↗
PubMed1986

Meiotic chromosome studies and synaptonemal complex analyses by light and electron microscopy in 47 infertile or sterile males.

Mitotic and meiotic chromosome studies and synaptonemal complex analyses by light and electron microscopy have been carried out in a selected series of 47 infertile or sterile males with highly abnormal seminograms, affecting the number of spermatozoa, their morphology and/or motility. In 46 cases, the karyotype was 46,XY. One patient had a 13/14 translocation. With the exception of the patient with a 13/14 translocation, and three patients with desynapsis (8.5%), all other cases showed either normal or absent metaphase I figures. However, synaptonemal complex analysis by light and electron microscopy demonstrated the presence of pairing anomalies (desynapsis, fragmented or irregular synaptonemal complexes) in 31.9% of the patients studied. The total number of synaptic anomalies observed (40.4%) is higher than in a former light microscopy study of 111 infertile or sterile patients (28.8%) probably because the higher resolution of the electron microscope permits the characterization of some anomalies that cannot be detected with the light microscope. The electron microscope should therefore be used in all cases in which the light microscope provides doubtful results.

Chromosomes, Human↗
PubMed1984

Meiotic studies and synaptonemal complex analysis in two infertile males with a 13/14 balanced translocation.

Meiotic and synaptonemal complex studies by light and electron microscopy have been carried out in two infertile males with a balanced 13/14 translocation. As expected, all metaphase I figures in conventional meiotic preparations contained a chain trivalent. Synaptonemal complex studies showed typical trivalent images with incomplete pairing of the acrocentric elements in the cis configuration. A review of the literature shows that the fertility of these patients is quite variable. All of them show a slightly reduced number of chiasmata (mean 46.6). Pairing in cis, as detected by electron microscopic studies, does not seem to have a prognostic value.

Adult↗
PubMed1984

Development and behavior of synaptonemal complexes in human spermatocytes by light and electron microscopy.

We describe in this paper the human male synaptic cycle using light and electron microscopy and the distribution of cells in the different stages of prophase I. The pattern of chromosome pairing and synapsis is an important tool to determine accurately whether a given synaptic behavior in infertile or sterile men is really abnormal or not. The relationship of prepachytene to pachytene cells is also important for the diagnosis of the different types of meiotic arrest at the primary spermatocyte level.

Cell Nucleus↗
PubMed1983

Meiotic studies in a series of 1100 infertile and sterile males.

Meiotic studies have been carried out in a series of 1100 infertile and sterile males. Of these, 599 cases have been studied in testicular biopsy, and 501, in semen samples. This is the largest meiotic series published so far. The incidence of meiotic anomalies was 4.3%. The most frequent chromosome abnormality was desynapsis (3.7%). However, the number of cases with a meiotic arrest, usually due (73.9%) to synaptic anomalies in prophase I, was much higher (18.4%). An attempt is made to correlate the incidence of meiotic anomalies with the results of semen analysis. We discuss the prognosis of desynapsis, based on 41 cases studied, and reevaluate the results obtained in semen samples as compared with our previous results.

Chromosome Aberrations↗