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Dive into the research topics where G. Barrenetxea is active.

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Featured researches published by G. Barrenetxea.


Gene | 2013

Study of FMR1 gene association with ovarian dysfunction in a sample from the Basque Country

Maitane Barasoain; G. Barrenetxea; Iratxe Huerta; Mercedes Télez; Amaia Carrillo; Cristina Pérez; Begoña Criado; Isabel Arrieta

Premature ovarian failure (POF) is defined as cessation of menses before the age of 40. The most significant single gene associated with POF is the Fragile X Mental Retardation 1 gene (FMR1). In the present work we screened women with fertility problems from the Basque Country in order to determine, whether in these women, FMR1 CGG repeat size in the intermediate and premutation range was associated with their pathology, and whether intermediate and premutation carriers had endocrine signs of diminished ovarian function, using the most established measure of ovarian reserve, the gonadotropin FSH. A patient sample of 41 women with ovarian insufficiency and a control sample of 32 women with no fertility problems from the Basque Country were examined. The patient sample was classified into three categories according to the results of the retrospective assessment of their ovarian function. In group 2 of patients, women with irregular cycles, reduced fecundity and FSH levels ≥ 10IU/l, there is a significant increase in the number of intermediate and premutation FMR1 alleles (35-54 CGG repeats). In group 3 of patients, women with amenorrhea for at least four consecutive months and FSH levels ≥ 10IU/l, a significant increase in the number of intermediate FMR1 alleles (35-54 CGG repeats) was found in patients compared with controls. In this group all the patients had a serum concentration > 40 IU/l. The results suggest that in the analysed Basque sample the FMR1 gene has a role in the aetiology of POF. However, elevated FSH levels are more related to the menstrual cycle pattern than to the CGG repeat size.


Genes | 2016

Study of the Genetic Etiology of Primary Ovarian Insufficiency: FMR1 Gene

Maitane Barasoain; G. Barrenetxea; Iratxe Huerta; Mercedes Télez; Begoña Criado; Isabel Arrieta

Menopause is a period of women’s life characterized by the cessation of menses in a definitive way. The mean age for menopause is approximately 51 years. Primary ovarian insufficiency (POI) refers to ovarian dysfunction defined as irregular menses and elevated gonadotrophin levels before or at the age of 40 years. The etiology of POI is unknown but several genes have been reported as being of significance. The fragile X mental retardation 1 gene (FMR1) is one of the most important genes associated with POI. The FMR1 gene contains a highly polymorphic CGG repeat in the 5′ untranslated region of exon 1. Four allelic forms have been defined with respect to CGG repeat length and instability during transmission. Normal (5–44 CGG) alleles are usually transmitted from parent to offspring in a stable manner. The full mutation form consists of over 200 repeats, which induces hypermethylation of the FMR1 gene promoter and the subsequent silencing of the gene, associated with Fragile X Syndrome (FXS). Finally, FMR1 intermediate (45–54 CGG) and premutation (55–200 CGG) alleles have been principally associated with two phenotypes, fragile X tremor ataxia syndrome (FXTAS) and fragile X primary ovarian insufficiency (FXPOI).


Mutation Research-genetic Toxicology and Environmental Mutagenesis | 2014

Genotoxic evaluation of five Angiotesin II receptor blockers: In vivo and in vitro micronucleus assay

Iratxe Huerta; Maitane Barasoain; Mercedes Télez; Mikel Longa; Javier Muga; G. Barrenetxea; Eduardo Ortiz-Lastra; Javier J. González; Begoña Criado; Isabel Arrieta

Angiotensin II receptor blockers (ARBs) are a new class of drugs for the treatment of hypertension. In this study, we studied the potential genotoxic effects of five ARBs in vivo and in vitro in human peripheral blood lymphocytes (PBLs) by means of the cytokinesis-block micronucleous (CBMN) assay in combination with fluorescence in situ hybridization (FISH) with a centromeric probe. The nuclear division index (NDI) was used as a measure of cytotoxicity. We also analyzed the association between sex, age, duration of treatment and MN formation. The in vivo study was carried out in 55 hypertensive patients. The in vitro study was performed in 10 control individuals by adding the drugs to the culture medium at a final concentration similar to the levels found in plasma in patients. Our results showed a significant increase in the frequencies of MN and binucleated cells with MN (BNMN) in vivo and especially in vitro. We observed variability in the mean frequency of MN and BNMN among the five drugs analyzed. In vivo, patients treated with Candesartan, Telmisartan and Valsartan showed a statistical significant increase in these parameters, while Olmesartan showed the highest effect in vitro. We also found that the drugs inhibit the NDI in vitro and that Eprosartan, Olmesartan and Telmisartan are the ARBs studied with the highest effect in decreasing the proliferation of the cells. FISH analysis revealed no significant difference between patients and controls in the frequency of centromeric signals. A slight variability, without statistical significance, in the frequency of micronuclei with a centromere signal (CN(+)MN) was found among the different ARBs analyzed, ruling out an aneugenic potential. When accounting for risk factors, we found that in patients there is a positive correlation between MN, BNMN and sex and a negative correlation with duration of treatment.


European Journal of Obstetrics & Gynecology and Reproductive Biology | 1995

Angiosarcoma of the breast and pregnancy : a new therapeutic approach

G. Barrenetxea; J. Schneider; J.G. Tánago; C. Pérez; M.M. Centeno; F.J. Rodriguez-Escudero

A case of angiosarcoma of the breast managed primarily by a chemotherapeutic approach is referred. A 29-year-old patient presented complaining of a painful mass in her right breast. An incisional biopsy carried out under general anesthesia showed a moderately-differentiated angiosarcoma surrounded by fibrofatty tissue. Ruled out distant metastases, a decision was made to initiate neoadjuvant chemotherapy consisting of ifosfamide, vincristine and dactinimycin. After 2 courses of chemotherapy the tumor volume was reduced by 50% and the histologic examination of the mastectomy specimen revealed a well-differentiated angiosarcoma with widespread areas of necrosis probably produced by previous chemotherapic treatment. The patient is clinically free of disease after 24 months of follow-up. Although this is a single case report, and by no means can be considered a guideline for future treatments, we nevertheless feel that the result obtained with the chemotherapeutic approach with this patient is encouraging.


European Journal of Obstetrics & Gynecology and Reproductive Biology | 2012

Iatrogenic prion diseases in humans: an update

G. Barrenetxea

Although Creutzfeldt-Jakob disease (CJD) was first identified in 1920, prevention of transmission raised particular concern all over the world when a new variant of the disease was first described in 1996. There is good evidence of iatrogenic transmission of this new variant among human beings through blood, blood components, tissues and growth hormone. Furthermore, four cases of iatrogenic transmission of CJD through fertility treatment with human pituitary-derived gonadotrophins have been reported. It is important to distinguish the categories of infectivity and categories of risk, which require consideration not only of the level of infectivity of a given tissue or fluid, but also the amount of tissue/fluid to which a person is exposed, the duration of exposure and the route by which infection is transmitted. The potential presence and infectivity of prion proteins in human urinary gonadotrophin preparations is a matter of debate. Differences in the sensitivity of bioassay methods are of paramount importance when considering the infectivity of a tissue. Some new methods might detect small amounts of agent in some tissues currently thought to be free of infectivity. No cases of human prion disease due to the use of urinary gonadotrophins have been recognized to date. However, the detection of prions in the urine of experimental animals and in some urine-based preparations, and the young age of fertility drug recipients, require the application of the precautionary principle to urinary preparations.


Annals of Human Genetics | 2012

Single nucleotide polymorphism and FMR1 CGG repeat instability in two Basque valleys.

Maitane Barasoain; G. Barrenetxea; Eduardo Ortiz-Lastra; Javier J. González; Iratxe Huerta; Mercedes Télez; Juan Manuel Ramírez; Amaia Domínguez; Paula Gurtubay; Begoña Criado; Isabel Arrieta

Fragile X Syndrome (FXS, MIM 309550) is mainly due to the expansion of a CGG trinucleotide repeat sequence, found in the 5′ untranslated region of the FMR1 gene. Some studies suggest that stable markers, such as single nucleotide polymorphisms (SNPs) and the study of populations with genetic identity, could provide a distinct advance to investigate the origin of CGG repeat instability. In this study, seven SNPs (WEX28 rs17312728:G>T, WEX70 rs45631657:C>T, WEX1 rs10521868:A>C, ATL1 rs4949:A>G, FMRb rs25707:A>G, WEX17 rs12010481:C>T and WEX10 ss71651741:C>T) have been analyzed in two Basque valleys (Markina and Arratia). We examined the association between these SNPs and the CGG repeat size, the AGG interruption pattern and two microsatellite markers (FRAXAC1 and DXS548). The results suggest that in both valleys WEX28‐T, WEX70‐C, WEX1‐C, ATL1‐G, and WEX10‐C are preferably associated with cis‐acting sequences directly influencing instability. But comparison of the two valleys reveals also important differences with respect to: (1) frequency and structure of “susceptible” alleles and (2) association between “susceptible” alleles and STR and SNP haplotypes. These results may indicate that, in Arratia, SNP status does not identify a pool of susceptible alleles, as it does in Markina. In Arratia valley, the SNP haplotype association reveals also a potential new “protective” factor.


Reproductive Biomedicine & Society Online | 2018

Comparative economic study of the use of corifollitropin alfa and daily rFSH for controlled ovarian stimulation in older patients: Cost-minimization analysis based on the PURSUE study

G. Barrenetxea; Juan Antonio García-Velasco; Belén Aragón; Jordi Osset; Max Brosa; Noemí López-Martínez; Buenaventura Coroleu

This study presents an economic assessment of controlled ovarian stimulation in assisted reproductive technology procedures in Spain, comparing the use of corifollitropin alfa and various forms of recombinant follicle-stimulating hormone (rFSH) in women of advanced maternal age. A cost-minimization analysis (CMA) was performed to assess the cost per cycle of controlled controlled ovarian stimulation, including only direct costs associated with the stimulation phase. The CMA was based on the population characteristics, the protocol, and the results obtained from the PURSUE study, taking into account 9 days of controlled controlled ovarian stimulation and 300 IU rFSH/day. The primary analysis included pharmacological costs alone. Different scenarios were evaluated including various doses and possible additional days (0–5) for rFSH. For the alternative analyses, the total costs (direct pharmacological costs, costs of visits and follow-up tests, and any additional pharmacological costs) were considered in both the private and public sectors. Treatment with corifollitropin alfa resulted in a lower pharmacological cost compared with rFSH (€757.25 and €950.30, respectively), creating a saving of approximately -20%. The results of the scenario analyses showed that corifollitropin alfa reduced the pharmacological cost of controlled ovarian stimulation in comparison with daily administration of doses ≥ 250 IU rFSH (considering same daily dose for all days), regardless of the additional days required (7–12 days) (average -€223; range -€488 to -€44). In conclusion, in addition to the efficacy shown in the PURSUE study, the use of corifollitropin alfa results in a decrease in the direct costs associated with controlled ovarian stimulation in older women in Spain.


International Journal of Gynecology & Obstetrics | 2009

P692 Improvements in the screening of semen donors

C. Anarte; J. De Pablo; J.A. Agirregoikoa; I. Ausin; M. Barreiro; G. Barrenetxea

the birth of an unaffected and HLA identical newborn in the second cycle. Umbilical Cord hematopoietic stem cells were obtained and frozen for subsequent transplantation. The affected child is currently on treatment for hematopoietic stem cell transplantation. Conclusion: Preimplantation genetic diagnosis in combination with human leukocyte antigen offers to families the possibility of having unaffected children, but also a new therapeutic option for a sibling who needs HLA identical hematopoietic stem cell transplantation as therapy. In such situation, PGD-HLA may be the only approach for curative treatment in many cases.


International Journal of Gynecology & Obstetrics | 2009

P689 Is there any negative influence in ICSI results by using frozen sperm

J. De Pablo; J.A. Agirregoikoa; C. Anarte; I. Ausin; M. Jiménez; S. Guerra; G. Barrenetxea

the birth of an unaffected and HLA identical newborn in the second cycle. Umbilical Cord hematopoietic stem cells were obtained and frozen for subsequent transplantation. The affected child is currently on treatment for hematopoietic stem cell transplantation. Conclusion: Preimplantation genetic diagnosis in combination with human leukocyte antigen offers to families the possibility of having unaffected children, but also a new therapeutic option for a sibling who needs HLA identical hematopoietic stem cell transplantation as therapy. In such situation, PGD-HLA may be the only approach for curative treatment in many cases.


Fertility and Sterility | 2007

Heterotopic pregnancy: two cases and a comparative review

G. Barrenetxea; Lorea Barinaga-Rementeria; Arantza Lopez de Larruzea; Jon Ander Agirregoikoa; Miren Mandiola; Koldo Carbonero

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J.A. Agirregoikoa

University of the Basque Country

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Iratxe Huerta

University of the Basque Country

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Isabel Arrieta

University of the Basque Country

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Maitane Barasoain

University of the Basque Country

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Mercedes Télez

University of the Basque Country

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Begoña Criado

Instituto Politécnico Nacional

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Koldo Carbonero

University of the Basque Country

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Eduardo Ortiz-Lastra

University of the Basque Country

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Javier J. González

University of the Basque Country

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Miren Mandiola

University of the Basque Country

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