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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Produção de embriões humanos através da injeção intracitoplasmática de espermatozóides obtidos do ejaculado, epidídimo ou testículo / Production of human embryos with intracytoplasmic injection of sperm obtained from ejaculate, epididymis and testis

Pimentel, Anita Mylius 18 August 2006 (has links)
This retrospective study compared rates of fertilization, cleavage and quality of human embryos obtained by intracytoplasmic sperm injection (ICSI), with sperm from ejaculate, epididymis and testis. A total of 398 cycles of patients with some kind of male infertility were included and 3991 oocytes were inseminated. The spermatozoa from epididymis and testis were surgically obtained. Fertilization and cleavage rates with sperm from ejaculate (75% and 73%, respectively) were higher (P<0,0001) than those with sperm from the testis (59,7% e 56,8%, respectively) and from epididymis (61,9% e 59,3%). The production of viable embryos (grade I and II) was higher (P=0,0135) when the oocytes where inseminated with ejaculate sperm (89,4%) in relation to sperm from epididymis (82,9%) and testis (85,7%).The percentages of pregnancy were not different among groups (37,8% EJAC group, 27,6% EPID and 36,8% TEST group). In conclusion, sperm from ejaculate have a higher production of viable embryos. However, when sperm from the testis and epididymis are used for ICSI, the production of viable embryos is also considerable and can be seen as success in the assisted reproduction techniques. / Este estudo retrospectivo avaliou as taxas de fertilização, clivagem e qualidade de embriões humanos obtidos através da injeção intracitoplasmática (ICSI) de espermatozóides provenientes do ejaculado, epidídimo ou testículo. Foram incluídos 398 ciclos de pacientes que apresentaram algum tipo de infertilidade masculina, sendo inseminados 3991 oócitos. Os espermatozóides do epidídimo e do testículo foram recuperados cirurgicamente. As taxas de fertilização e de clivagem com espermatozóides do ejaculado (74,5% e 73%, respectivamente) foram maiores (P<0,0001) do que as do testículo (59,7% e 56,8%, respectivamente) e do epidídimo (61,9% e 59,3%). A produção de embriões viáveis (grau I e II) foi maior (P = 0,0135) quando os oócitos foram inseminados com espermatozóides do ejaculado (89,4%), em relação ao epidídimo (82,9%) e testículo (85,7%). As taxas de gestação não foram diferentes entre os grupos (37,8% no grupo EJAC, 27,6% EPID e 36,8% no grupo TEST). Em conclusão, espermatozóides do ejaculado produzem um maior número de embriões viáveis, com maiores taxas de fertilização e de clivagem. Entretanto, quando utilizados espermatozóides do epidídimo e do testículo na ICSI, a produção de embriões viáveis é considerável, obtendo êxito nas técnicas de reprodução assistida.
62

A "Cegonha tecnológica" no caminho do projeto parental : dialogando com a experiência de homens (in) férteis

Silva, Ellen Fernanda Gomes da 30 April 2014 (has links)
Made available in DSpace on 2017-06-01T18:08:53Z (GMT). No. of bitstreams: 1 ellen_fernanda_gomes_silva.pdf: 700030 bytes, checksum: 3c2c471bbb16fa66bf3657520388bf79 (MD5) Previous issue date: 2014-04-30 / The present research had the aim to understand the experience of infertile men. Specifically, it focused on masculinity and infertility interpretations, contextualizing them in contemporaneity; it also presented an existential phenomenological perspective as a possibility to thematize the body phenomenon as an expression of existence; as well as it described and understood the experience of infertile men who searched for the Assisted Human Reproduction service from the Institute of Integral Medicine of Pernambuco IMIP. This investigation is of qualitative nature, linked to the hermeneutic phenomenological perspective that privileges Gadamer s Philosophical Hermeneutic and Heideggerian ontological comprehensions. Narratives from collaborators and from the researcher s field journal were used in order to access such experience. Collaborators reports pointed to difficulties during the attempt for Assisted Reproduction methods, which led to uncomfortable experiences, as well as a lack of hope face to the services bureaucracy and slowness. The possibility of artificial procreation was revealed with certain awkwardness, with highlights to the over-valorization of biological parenthood. In such scenario, interlocutors narrated what they have lived regarding technical/medical procedures, unveiling, on one side, the utility of the technique for the parental project and, on the other side, the domain of scientific discourse, as well as the comprehension of men s bodies as raw material to be explored and improved. / A presente pesquisa teve como objetivo geral compreender a experiência de homens que vivenciam a infertilidade. E, especificamente, enfocou interpretações da masculinidade e infertilidade, contextualizando-as na contemporaneidade; apresentou a perspectiva fenomenológica existencial como possibilidade para tematizar o fenômeno do corpo enquanto expressão da existência; bem como descreveu e compreendeu a experiência de homens, na condição de inférteis, os quais procuram o serviço de Reprodução Humana Assistida do Instituto de Medicina Integral de Pernambuco IMIP. De natureza qualitativa, esta investigação está afinada à perspectiva fenomenológica hermenêutica, privilegiando a compreensão interpretativa fundada na Hermenêutica Filosófica de Gadamer, vinculada às compreensões ontológicas heideggerianas. Para acesso à experiência foi escolhida a narrativa, colhida tanto dos colaboradores, quanto dos registros feitos no diário de bordo da pesquisadora, a partir da sua inserção no lócus da pesquisa. Os relatos dos colaboradores apontaram para dificuldades vividas durante a tentativa de métodos de Reprodução Assistida, as quais levaram a experiências de desconforto, bem como de desesperança frente a burocracia e morosidade dos serviços. Aproximando-se desta via compreensiva, a possibilidade de procriação artificial foi revelada com certa estranheza, ressaltando a supervalorização da parentalidade biológica. Em tal cenário, os interlocutores narraram sua vivência frente aos procedimentos técnicos/médicos, desvelando de um lado a utilidade da técnica no projeto parental e, de outro, o seu domínio na hegemonia do discurso científico, bem como na compreensão do corpo masculino como matéria-prima a ser explorada e aperfeiçoada.
63

Imagerie Avancée du testicule : Echographie et IRM multiparamétriques / Advanced Testis Imaging : Multiparametric Ultrasound and MRI

Rocher, Laurence 09 December 2016 (has links)
Résumé : L’imagerie testiculaire développée dans notre unité a deux thématiques principales : l’infertilité et la caractérisation tumorale. Cette imagerie est basée sur l’échographie et l’IRM multiparamétriques. Nous avons défini des critères diagnostiques pour différentes pathologies, ayant un impact sur la prise en charge des patients, et évalué des modalités innovantes.Nous avons caractérisé l’aspect des testicules de patients infertiles porteurs d’un syndrome de Klinefelter. Nous avons déterminé l’aspect en Mode B et en Doppler couleur des tumeurs à cellules de Leydig dont la plupart sont actuellement découvertes de façon fortuite et peuvent bénéficier d’une surveillance ou d’une tumorectomie. Nous avons défini les critères diagnostiques des tumeurs éteintes ou «burned out tumors» découvertes en écho-Doppler chez des patients adressés pour bilan d’infertilité.Nous avons montré la capacité de l’IRM multiparamétrique à améliorer la caractérisation tumorale, par l’analyse qualitative et quantitative du rehaussement et par la valeur du coefficient de diffusion (ADC).L’échographie de contraste a montré des différences significatives entre les tumeurs éteintes et les autres lésions.L’élastographie par onde de cisaillement a montré des différences de dureté entre les testicules des patients infertiles par mécanisme obstructif et non obstructif mais le chevauchement des valeurs minimise l’impact clinique potentiel. Les tumeurs bénignes à cellules de Leydig étaient plus molles que les tumeurs malignes et les tumeurs éteintes. Le couplage des informations données par le mode B, le Doppler couleur, et l’élastographie ont permis une caractérisation optimale.Le Doppler ultrasensible a permis une analyse qualitative de l’architecture vasculaire des tumeurs, de la vascularisation testiculaire dans les urgences scrotales et une quantification de la vascularisation testiculaire. Nous avons objectivé une diminution de la vascularisation testiculaire pendant la manœuvre de Valsalva chez les patients avec varicocèle, ce qui représente une explication physiopathologique à l’infertilité par mécanisme hypoxique. / The testicular imaging we developped in our department focused on two main subjects: infertility and tumoral characterization. It is based on multiparametric ultrasound and MRI. We defined diagnostic criteria of several pathologies, which may change the patient’s management, and we evaluated new modalities.We characterized Klinefelter patient’s testis.We determined the Color-Doppler features of Leydig cell tumors which are currently incidentally discovered and can benefit from monitoring or tumorectomy.We defined multiparametric US and MRI diagnostic’s criteria of burned out tumors in patients referred for US infertility screening.We demonstrated the ability of multiparametric MRI to improve the tumoral characterization using qualitative and quantitative enhancement parameters and apparent diffusion coefficient values.CEUS showed significant differences between the burned out tumors and other lesions.. Shear Wave Elastography (SWE) showed significant differences in testicular stiffness between normal, obstructive azoospermia on one side and non-obstructive azoospermic patients, but overlapped values seemed to minimize the potential clinical impact. Benign Leydig cell were softer compared to malignant tumors and burned out tumors. Association of B mode, color Doppler, and elastography allowed an optimal characterization.Ultrasensitive Doppler allowed a qualitative evaluation of the tumoral vascular architecture, a testicular vascularization assessment in case of acute scrotum, and a testicular perfusion quantification. We demonstrated a decreased testicular vascularization during the Valsalva maneuver confirming the hypoxic physiopathological explanation of the infertility process.
64

Knockout mouse model generated by CRISPR technology to study the function of BSP proteins on male fertility in vivo

Eskandari Shahraki, Marzieh 04 1900 (has links)
No description available.
65

Interactions of the Human Recombinant Proteins JUNO and IZUMO1 / Interaktioner mellan de mänskliga, rekombinanta proteinerna JUNO och IZUMO1

Lundell, Emma January 2020 (has links)
Det uppskattas att 15% av alla par världen över lider avinfertilitet. Ungefär hälften beror på manlig infertilitet och 40% av dessa fall kan ännu inte förklaras. Därmed är nuvarande metoder för att diagnostisera manlig infertilitet otillräckliga och ytterligare tekniker behövs. En lyckad befruktning kräver att spermierna uttrycker membranproteinet Izumo1 som måste känna igen dess receptorprotein Juno, belägen vid ytan av äggmembranet. Bindningen mellan Juno och Izumo1 är essentiell för befruktning hos däggdjur då den bidrar till att gameternabinder och skapar en ny distinkt organism. Juno är ett relativt nyupptäckt protein och mekanismen med Izumo1 är fortfarande okänd. Ett nystartat företag vid namn Spermosens vill mäta interaktionen mellan Juno ochIzumo1 i ett nytt diagnostikverktyg som ska diagnostisera manlig infertilitet. Tanken är att Juno ska immobiliseras på guld-nanopartiklar och användas för att mätainteraktionen med spermaprover. Det nya verktyget ska hjälpa par att fastställa felet i befruktningen, vilket som en följd skulle hjälpa paret att välja lämplig assisteradreproduktionsmetod. I utvecklingen av det nya diagnostikverktyget behöver det konfirmeras att den Juno som används i enheten kan binda korrekt till mänskligt Izumo1. Därför måste interaktionerna mellan de mänskliga, rekombinanta proteinerna Juno och Izumo1 mätas och karakteriseras. Syftet med detta projekt var att utveckla en metod för att immobilisera Juno på guldnanopartiklar och sedan mäta interaktionerna med Izumo1 genom UV-Visspektroskopi. Detta är teoretiskt möjligt eftersom guld-nanopartiklarna framkallar ett fenomen som kallas lokaliserad ytplasmonresonans som varierar beroende påstorleken på guld-nanopartikelkomplexet. Immobiliseringsmetoden var en process som involverade flera steg som designades, polerades och förbättrades underarbetets gång. Dithiobis(C2-NTA) konjugerades till guldytan och koboltjonerkonjugerades till NTA. Det sista steget som innebar konjugering av Juno till kobolt genom en His-tag lyckades inte, och interaktionerna kunde därför inte mätas genom denna metod. Istället mättes protein-protein-interaktionen genom SPR-mätningar med Biacore, ett instrument som också är baserat på ytplasmonresonans. Interaktioner mellan Izumo1 och Juno kunde uppmätas både vid användning av Juno producerad från E. coli ochfrån däggdjursceller. Dissociationskonstanten (Kd) beräknades till 7-33 nM (för Junooch Izumo1 producerade i däggdjursceller) vilket kan jämföras med ett experimentfrån 2016 där 48 nM beräknades. Ett mer exakt Kd kunde inte fastställas och entrolig anledning till detta var att regenereringen av sensorytan som utfördes med NaOH varierade i effektivitet, vilket ledde till en osäkerhet då ytförhållandena kan ha varierat mellan mätningarna. De två Juno-proteinerna, som är producerade i olika organismer, visade två skilda affinitetsprofiler med Izumo1 vilket tyder på att glykosyleringen påverkar bindningsmekanismen mellan Juno och Izumo1. / It is estimated that 15% of all couples worldwide suffer from infertility. Roughly half is male-factor infertility and 40% of these cases cannot be explained. Thus, current methods for diagnosing male infertility are not enough and further techniques are needed. To have a successful fertilisation event, it is required that the sperm expresses membrane surface-protein Izumo1 which must recognise its counterpart protein Juno, located at the surface of the egg membrane. The recognition step between Juno and Izumo1 is essential in mammalian fertilisation for the gametes to bind and start the creation of a new distinct organism, but the molecular mechanism is still unknown.A start-up company named Spermosens want to measure the Juno-Izumo1 interaction in a new diagnostic device designed to diagnose male infertility. The idea is to have Juno immobilised on gold nanoparticles and measure the interaction between Juno and various semen samples. The new device is supposed to help couples pin-point the procreation issue which would help in the selection of suitable assisted reproductive technology. In the development of the new device, it had to be established that the Juno used in the device will bind correctly to human Izumo1. Therefore, the interactions between the human recombinant proteins Juno and Izumo1 had to be measured and characterized.The objectives of this project were to develop a method to immobilise Juno on gold nanoparticles and then measure the interactions with Izumo1 using UV-vis spectroscopy. This is theoretically possible since the gold nanoparticles exhibit a phenomenon called localized surface plasmon resonance that vary depending on the size of the gold nanoparticle-complex. The immobilisation procedure was a process involving several steps that were designed, polished and improved along the way. Dithiobis(C2-NTA) was conjugated to the gold surface and a cobalt ion was conjugated to the NTA. The last step involving conjugation of Juno to the cobalt through a His-tag was not succeeded, and the interactions could therefore not be measured this way.Instead, the protein-protein interaction was measured through SPR-measurements using Biacore, an instrument that is based on surface plasmon resonance as well. Interactions between Izumo1 and Juno could be detected using Juno produced in E. coli and in mammalian cells. The dissociation constant (Kd) could be calculated to 7-33 nM which can be compared to a previously published Kd of 48 nM. A more precise Kd could not be established, possibly due to that the regeneration of the sensor surface with NaOH varied in efficiency, leading to changing surface conditions during the measurements. The two Juno proteins, that were produced in different hosts, showed two different affinity profiles with Izumo1, which contributes to the suggestion that the glycosylation plays a role in the binding mechanism between Juno and Izumo1.
66

Comparaison de deux nouvelles méthodes d’évaluation de la fertilité masculine avec le spermogramme chez des patients ayant recours à la fécondation in vitro

Courchesne, Annick 12 1900 (has links)
Des facteurs masculins sont identifiés dans près de la moitié des cas d’infertilité. À ce jour, les tests évaluant la fertilité masculine demeurent peu prédictifs de la survenue d’une grossesse. Dans le but de pallier cette lacune, nous avons mis au point deux nouveaux tests mesurant l’intégrité de l’ADN et le temps de survie des spermatozoïdes. Nous avons effectué une étude prospective portant sur 42 couples infertiles suivis en fécondation in vitro (FIV). Le spermogramme a été effectué selon les critères de l’Organisation Mondiale de la Santé (OMS) et le temps de survie des spermatozoïdes exposés à un détergent cationique a été mesuré en observant la mobilité sous microscope. L’intégrité de l’ADN des spermatozoïdes a été vérifiée par la nouvelle méthode de marquage radioenzymatique et par analyse de la structure de la chromatine (SCSA). Tous les tests ont été réalisés sur la partie des échantillons de sperme non utilisée par la clinique de fertilité. Le projet a été approuvé par le comité d’éthique du Centre Hospitalier Universitaire de Montréal (CHUM) et les patients ont préalablement signé un formulaire de consentement éclairé. L’analyse des paramètres du spermogramme et de l’intégrité de l’ADN n’a montré aucune différence statistiquement significative entre les données chez les couples avec ou sans grossesse. Cependant, le taux de grossesse biochimique était statistiquement plus élevé chez les couples dont le temps de survie des spermatozoïdes était long (>250 s) comparativement à ceux dont ce temps était court (≤250 s): 66% vs 27% respectivement (p<0,05). Les taux de grossesse clinique et d’implantation étaient aussi plus élevés, mais les différences n’atteignaient pas le seuil de signification statistique. Nos résultats confirment que le spermogramme et la mesure de la fragmentation de l’ADN des spermatozoïdes ne sont pas de bons facteurs prédictifs des résultats de la FIV. Par contre, le test de survie des spermatozoïdes serait un meilleur indicateur de la possibilité d’une grossesse en FIV. L’amélioration de sa spécificité et un plus grand nombre de sujets sont nécessaires avant de proposer son application en clinique de fertilité. / Male factors are known to be involved in almost half of the couples consulting for infertility. To date, the tests for evaluating male fertility are poor predictors of pregnancy. We developed two new tests to evaluate sperm function: a sperm survival test and a new method to measure sperm DNA integrity. This prospective study was conducted on 42 infertile couples undergoing in vitro fertilization (IVF). Assessment of sperm parameters was done according to the World Health Organization (WHO) criteria, and sperm survival upon exposure to a cationic detergent was measured by observing motility under the microscope. Sperm DNA integrity was verified by our new radioenzymatic method as well as by the sperm chromatin structure analysis (SCSA) method. All testing was performed on a remainder aliquot of the semen samples. The study was approved by the ethics committee of the Centre Hospitalier Universitaire de Montréal (CHUM), and informed consent was obtained before inclusion. Neither conventional semen analysis, nor sperm DNA fragmentation showed statistically significant difference between conception and non-conception cycles. However, the biochemical pregnancy rate was statistically higher in couples where the sperm survival time was long (>250 s) compared to short (≤250 s): 66% vs. 27% respectively, (p < 0.05). The clinical pregnancy rate and implantation rate were also higher but the differences did not reach statistical significance. Our study confirms that conventional semen analysis and the assay for sperm DNA integrity are not reliable indicators of IVF outcome. In contrast, our new sperm survival test seems to be a better predictor of the pregnancy rate after IVF. Improvement of its specificity and a larger cohort of patients are necessary before proposing its regular application in IVF clinics.
67

Detecção de microdeleções do cromossomo Y em pacientes inférteis, comparando os resultados obtidos pelas técnicas de PCR e MLPA / Detection of Y chromosome microdeletions in infertile patients, comparing the results obtained by PCR and MLPA techniques

Camila Sommerauer Franchim 25 September 2018 (has links)
INTRODUÇÃO: O cromossomo Y contém genes primordiais para o desenvolvimento testicular e a espermatogênese. Sua conformação repetitiva predispõe à ocorrência de deleções e duplicações, que tem impacto clínico. As microdeleções nas regiões AZF afetam loci responsáveis pela espermatogênese e são uma das causas mais frequentes de azoospermia e oligozoospermia. Seu diagnóstico tem valor preditivo para o sucesso na recuperação cirúrgica de espermatozoides testiculares em homens azoospérmicos. A técnica utilizada para detectá-las é a reação de polimerização em cadeia (PCR), porém os protocolos divergem entre si, havendo muita variabilidade na incidência destas deleções. À vista disso, sugerimos utilizar a técnica de Amplificação de Múltiplas Sondas dependente de Ligação (MLPA). OBJETIVO: Comparar os resultados obtidos com as técnicas de PCR e MLPA na detecção de microdeleções do cromossomo Y em homens inférteis. RESULTADOS: Analisamos 43 pacientes inférteis (azoospérmicos e oligozoospérmicos) e 40 homens férteis (controle) pelas técnicas de PCR e MLPA. Encontramos 7 deleções por PCR (16,2%) e 9 por MLPA (21%), além de 5 duplicações e um mosaico. DISCUSSÂO: Além das deleções, as duplicações também podem gerar instabilidades nos genes do cromossomo, podendo levar a infertilidade. CONCLUSÕES: Os resultados obtidos por ambas as técnicas revela que a MLPA é uma técnica mais sensível que a técnica de PCR para detectar microdeleções do cromossomo Y / INTRODUCTION: The Y chromosome contains several genes responsible for testicular development and spermatogenesis. Its repetitive conformation predisposes this chromosome to deletions and duplications that have clinical impact. Microdeletions in the AZF regions affect loci responsible for spermatogenesis and are one of the most frequent causes of azoospermia and oligozoospermia. This diagnosis may have a predictive value for success in the surgical recovery of testicular spermatozoa in azoospermic men. The gold standard method for this detection is polymerase chain reaction (PCR), but protocols diverge among them, generating a great variability in the incidence of these deletions. PURPOSE: We evaluated another molecular diagnostic method, Multiplex Ligand Probe Dependent Amplification (MLPA), which generates more genomic data (such as duplications and rearrangements) in a single reaction, leading to a better understanding of these patients phenotype. OBJECTIVE: To compare the results obtained with PCR and MLPA techniques in the detection of Y chromosome microdeletions in infertile men. RESULTS: We analyzed 43 infertile patients (azoospermic and oligozoospermic) and 40 fertile men (control) by PCR and MLPA techniques. We found 7 deletions by PCR (16.2%) and 9 by MLPA (21%), in addition to 5 duplications and one mosaic. DISCUSSION: Besides deletions, duplications can also generate instability in the chromosome genes, which may lead to infertility, and it is important being capable to diagnose these alterations with a faster and more effectively method. CONCLUSIONS: The results obtained by both techniques reveal that MLPA is more sensitive than PCR to detect microdeletions of the Y chromosome
68

Detecção de microdeleções do cromossomo Y em pacientes inférteis, comparando os resultados obtidos pelas técnicas de PCR e MLPA / Detection of Y chromosome microdeletions in infertile patients, comparing the results obtained by PCR and MLPA techniques

Franchim, Camila Sommerauer 25 September 2018 (has links)
INTRODUÇÃO: O cromossomo Y contém genes primordiais para o desenvolvimento testicular e a espermatogênese. Sua conformação repetitiva predispõe à ocorrência de deleções e duplicações, que tem impacto clínico. As microdeleções nas regiões AZF afetam loci responsáveis pela espermatogênese e são uma das causas mais frequentes de azoospermia e oligozoospermia. Seu diagnóstico tem valor preditivo para o sucesso na recuperação cirúrgica de espermatozoides testiculares em homens azoospérmicos. A técnica utilizada para detectá-las é a reação de polimerização em cadeia (PCR), porém os protocolos divergem entre si, havendo muita variabilidade na incidência destas deleções. À vista disso, sugerimos utilizar a técnica de Amplificação de Múltiplas Sondas dependente de Ligação (MLPA). OBJETIVO: Comparar os resultados obtidos com as técnicas de PCR e MLPA na detecção de microdeleções do cromossomo Y em homens inférteis. RESULTADOS: Analisamos 43 pacientes inférteis (azoospérmicos e oligozoospérmicos) e 40 homens férteis (controle) pelas técnicas de PCR e MLPA. Encontramos 7 deleções por PCR (16,2%) e 9 por MLPA (21%), além de 5 duplicações e um mosaico. DISCUSSÂO: Além das deleções, as duplicações também podem gerar instabilidades nos genes do cromossomo, podendo levar a infertilidade. CONCLUSÕES: Os resultados obtidos por ambas as técnicas revela que a MLPA é uma técnica mais sensível que a técnica de PCR para detectar microdeleções do cromossomo Y / INTRODUCTION: The Y chromosome contains several genes responsible for testicular development and spermatogenesis. Its repetitive conformation predisposes this chromosome to deletions and duplications that have clinical impact. Microdeletions in the AZF regions affect loci responsible for spermatogenesis and are one of the most frequent causes of azoospermia and oligozoospermia. This diagnosis may have a predictive value for success in the surgical recovery of testicular spermatozoa in azoospermic men. The gold standard method for this detection is polymerase chain reaction (PCR), but protocols diverge among them, generating a great variability in the incidence of these deletions. PURPOSE: We evaluated another molecular diagnostic method, Multiplex Ligand Probe Dependent Amplification (MLPA), which generates more genomic data (such as duplications and rearrangements) in a single reaction, leading to a better understanding of these patients phenotype. OBJECTIVE: To compare the results obtained with PCR and MLPA techniques in the detection of Y chromosome microdeletions in infertile men. RESULTS: We analyzed 43 infertile patients (azoospermic and oligozoospermic) and 40 fertile men (control) by PCR and MLPA techniques. We found 7 deletions by PCR (16.2%) and 9 by MLPA (21%), in addition to 5 duplications and one mosaic. DISCUSSION: Besides deletions, duplications can also generate instability in the chromosome genes, which may lead to infertility, and it is important being capable to diagnose these alterations with a faster and more effectively method. CONCLUSIONS: The results obtained by both techniques reveal that MLPA is more sensitive than PCR to detect microdeletions of the Y chromosome
69

Comparaison de deux nouvelles méthodes d’évaluation de la fertilité masculine avec le spermogramme chez des patients ayant recours à la fécondation in vitro

Courchesne, Annick 12 1900 (has links)
Des facteurs masculins sont identifiés dans près de la moitié des cas d’infertilité. À ce jour, les tests évaluant la fertilité masculine demeurent peu prédictifs de la survenue d’une grossesse. Dans le but de pallier cette lacune, nous avons mis au point deux nouveaux tests mesurant l’intégrité de l’ADN et le temps de survie des spermatozoïdes. Nous avons effectué une étude prospective portant sur 42 couples infertiles suivis en fécondation in vitro (FIV). Le spermogramme a été effectué selon les critères de l’Organisation Mondiale de la Santé (OMS) et le temps de survie des spermatozoïdes exposés à un détergent cationique a été mesuré en observant la mobilité sous microscope. L’intégrité de l’ADN des spermatozoïdes a été vérifiée par la nouvelle méthode de marquage radioenzymatique et par analyse de la structure de la chromatine (SCSA). Tous les tests ont été réalisés sur la partie des échantillons de sperme non utilisée par la clinique de fertilité. Le projet a été approuvé par le comité d’éthique du Centre Hospitalier Universitaire de Montréal (CHUM) et les patients ont préalablement signé un formulaire de consentement éclairé. L’analyse des paramètres du spermogramme et de l’intégrité de l’ADN n’a montré aucune différence statistiquement significative entre les données chez les couples avec ou sans grossesse. Cependant, le taux de grossesse biochimique était statistiquement plus élevé chez les couples dont le temps de survie des spermatozoïdes était long (>250 s) comparativement à ceux dont ce temps était court (≤250 s): 66% vs 27% respectivement (p<0,05). Les taux de grossesse clinique et d’implantation étaient aussi plus élevés, mais les différences n’atteignaient pas le seuil de signification statistique. Nos résultats confirment que le spermogramme et la mesure de la fragmentation de l’ADN des spermatozoïdes ne sont pas de bons facteurs prédictifs des résultats de la FIV. Par contre, le test de survie des spermatozoïdes serait un meilleur indicateur de la possibilité d’une grossesse en FIV. L’amélioration de sa spécificité et un plus grand nombre de sujets sont nécessaires avant de proposer son application en clinique de fertilité. / Male factors are known to be involved in almost half of the couples consulting for infertility. To date, the tests for evaluating male fertility are poor predictors of pregnancy. We developed two new tests to evaluate sperm function: a sperm survival test and a new method to measure sperm DNA integrity. This prospective study was conducted on 42 infertile couples undergoing in vitro fertilization (IVF). Assessment of sperm parameters was done according to the World Health Organization (WHO) criteria, and sperm survival upon exposure to a cationic detergent was measured by observing motility under the microscope. Sperm DNA integrity was verified by our new radioenzymatic method as well as by the sperm chromatin structure analysis (SCSA) method. All testing was performed on a remainder aliquot of the semen samples. The study was approved by the ethics committee of the Centre Hospitalier Universitaire de Montréal (CHUM), and informed consent was obtained before inclusion. Neither conventional semen analysis, nor sperm DNA fragmentation showed statistically significant difference between conception and non-conception cycles. However, the biochemical pregnancy rate was statistically higher in couples where the sperm survival time was long (>250 s) compared to short (≤250 s): 66% vs. 27% respectively, (p < 0.05). The clinical pregnancy rate and implantation rate were also higher but the differences did not reach statistical significance. Our study confirms that conventional semen analysis and the assay for sperm DNA integrity are not reliable indicators of IVF outcome. In contrast, our new sperm survival test seems to be a better predictor of the pregnancy rate after IVF. Improvement of its specificity and a larger cohort of patients are necessary before proposing its regular application in IVF clinics.
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Μελέτη και σχεδίαση συστήματος ανάλυσης εικόνας κατατμημένου σπερματικού DNA με χρήση τεχνικών υπολογιστικής νοημοσύνης / Study and design of an image analysis system for sperm DNA fragmentation using computational intelligence techniques

Αλμπάνη, Ελένη 13 July 2010 (has links)
Ιατρικές έρευνες έχουν δείξει ότι η ανδρική υπογονιμότητα σχετίζεται άμεσα με την ύπαρξη κατατμημένου DNA στον πυρήνα των σπερματοζωαρίων. Οι διαταραχές στις τιμές της συγκέντρωσης σπερματοζωαρίων, της κινητικότητάς τους, του όγκου της εκσπερμάτισης και στη μορφολογία τους που παρατηρούνται σε ένα σπερμοδιάγραμμα έχουν σα βαθύτερο αίτιο την ύπαρξη κατατμημένου DNA. Το εργαστήριο πειραματικής εμβρυολογίας και ιστολογίας της Ιατρικής Αθηνών χρησιμοποιεί τη μέθοδο TUNEL (deoxynucleotidyl transferase-mediated dUTP nick end labeling) για να σηματοδοτήσει τα άκρα κάθε τμήματος του DNA με χρώμα διαφορετικό από αυτό που χρησιμοποιεί για το υπόλοιπο τμήμα του DNA. Αποτέλεσμα της επεξεργασίας που υφίστανται τα σπερματοζωάρια σε μια αντικειμενοφόρο πλάκα είναι ένα σύνολο από μπλε φθορίζοντα σπερματοζωάρια με πιθανό κόκκινο στο πυρήνα τους, στην περίπτωση που υπάρχει κατατμημένο DNA. Όσο μεγαλύτερος είναι ο βαθμός κατάτμησης, τόσο περισσότερο είναι το κόκκινο και τόσο περισσότερο παθολογικό το σπερματοζωάριο και άρα λιγότερο ικανό να γονιμοποιήσει. Τη διαδικασία της TUNEL ακολουθεί η φωτογράφηση της αντικειμενοφόρου πλάκας με κάμερα υψηλής ανάλυσης και μεγάλης ευαισθησίας, ειδική για εφαρμογές φθορισμού. Στη συνέχεια, οι εικόνες επεξεργάζονται με ειδικό λογισμικό, όπως έχει προταθεί στο «Automatic Analysis of TUNEL assay Microscope Images» από τους Kontaxakis et al. στο 2007 IEEE International Symposium on Signal Processing and Information Technology. Το αποτέλεσμα της επεξεργασίας των εικόνων είναι η ταξινόμηση των αντικειμένων που απεικονίζονται σε ομάδες από α) σπερματοζωάρια μονήρη β) επικαλυπτόμενα και γ) «σκουπίδια» όπως λευκοκύτταρα ή θραύσματα σπερματοζωαρίων. Στη συνέχεια για κάθε μονήρες σπερματοζωάριο γίνεται ο υπολογισμός των κόκκινων και μπλε pixels. Κατ’ αυτό τον τρόπο έχουμε ποσοτικοποιημένη την έκταση του κερματισμού κάθε σπερματοζωαρίου. Στόχος της διπλωματικής εργασίας είναι αρχικά η μελέτη και στη συνέχεια η σχεδίαση και υλοποίηση ενός συστήματος, το οποίο λαμβάνοντας υπόψη τα δεδομένα από την επεξεργασία εικόνας καθώς και δεδομένα που είναι γνωστά από το σπερμοδιάγραμμα, όπως η κινητικότητα και η συγκέντρωση των σπερματοζωαριών, χρησιμοποιώντας τεχνικές της υπολογιστικής νοημοσύνης θα εκπαιδεύεται και θα ταξινομεί αυτόματα ασθενείς ανάλογα με το συνολικό βαθμό κερματισμού του DNA τους. Τέλος, θα υπολογίζει και ένα κατώφλι ή μία περιοχή τιμών άνω της οποίας ένας ασθενής θα χαρακτηρίζεται ως στείρος. Απώτερος στόχος είναι να γίνει όλη η παραπάνω διαδικασία ένας έλεγχος ρουτίνας για τα εργαστήρια που ασχολούνται με την ανδρική υπογονιμότητα και την τεχνητή γονιμοποίηση, προφυλάσσοντας ζευγάρια από άσκοπες και επιβλαβείς για την υγεία της γυναίκας προσπάθειες τεχνητής γονιμοποίησης. / Studies have proven that male infertility is directly connected with the existence of fragmented DNA in sperm nucleus Structural disorders and functional abnormalities are often present in spermatozoa from infertile men, as they are the impact of DNA fragmentation. The histology and embryology laboratory in Medical School in Athens uses the TUNEL assay to mark the edges of DNA helix with color different from the rest of the helix. The result of this procedure is that the human spermatozoa are blue and in the interior of every cell, an area proportional to the degree of the cell DNA fragmentation has been stained in reddish color. The more reddish the area is, the more fragmented the DNA is and the more infertile the patient is. The TUNEL assay is followed by image collection using a camera of high sensitivity appropriate for fluorescence applications. Afterwards, the obtained images are processed as described in “Automatic Analysis of TUNEL assay Microscope Images” at IEEE International Symposium on Signal Processing and Information Technology in 2007. The results of the processing above is image segmentation, shapes classification in 3 groups, solitary spermatozoa, overlapped spermatozoa and debris and at last the area measurement of red pixel for each solitary spermatozoon. This way, we have in numbers how much fragmented the DNA is. This master thesis aims at the study and the design of a system, that taking into consideration the data from the image analysis accompanied by the data from the basic sperm analysis, like sperm concentration and motility, and using computational intelligence techniques, it will be trained and will automatically classify the patients according their DNA fragmentation degree. In the end, it will estimate a threshold or an area of values above which a patient will be considered as infertile. Our ultimate goal is the above procedure to be a routine for the labs that are dealing with male infertility and artificial insemination, so that couples are protected against pointless and prejudicial artificial insemination attempts.

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