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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.
31

Impact des facteurs maternels et paternels sur les résultats de FIV / ICSI et investigations génétiques des spermatozoïdes d'hommes infertiles / Impact of maternal and paternal factors on the results of IVF / ICSI and genetic investigations on the spermatozoa of infertile men

El Fekih, Sahar 20 December 2018 (has links)
L’infertilité concerne 8 à 12% des couples en âge de procréer. Face à ce problème, des prises en charge médicales peuvent être proposées comme la fécondation in vitro (FIV) et l’injection intracytoplasmique de spermatozoïde (ICSI). Toutefois, le taux d’échec de ces techniques reste relativement élevé. Dans la première partie, l’impact des facteurs maternels et paternels sur les résultats de 194 cycles de FIV et 586 cycles d’ICSI a été étudié. L’âge maternel, le nombre d’ovocytes ponctionnés et matures influencent principalement les résultats. Ni l’âge paternel ni les paramètres spermatiques (numération et mobilité) ne s’associent significativement à l’échec des techniques d’assistance médicale à la procréation (AMP). Seule la morphologie du spermatozoïde injecté a une influence sur la fécondation en ICSI. En deuxième partie, l’apoptose, la fragmentation de l’ADN et le contenu chromosomique avant et après tri cellulaire à l’aide des microbilles magnétiques ont été étudiés chez des hommes avec un taux de fragmentation de l’ADN spermatique anormal et chez des hommes porteurs d’une anomalie chromosomique constitutionnelle. Une diminution significative des spermatozoïdes apoptotiques avec un ADN fragmenté et chromosomiquement déséquilibrés a été observée. Le tri cellulaire aboutissant à une sélection de spermatozoïdes de meilleure qualité pourrait s’avérer une méthode de référence pour l’AMP. Dans une troisième partie, un protocole fiable a été élaboré pour étudier le transcriptome des spermatozoïdes. La mise au point de ces technologies permettra de mieux comprendre les causes d’échec des techniques d’AMP et ainsi améliorer leur taux de réussite. / Infertility concerns 8-12% of couples of reproductive age. Various medical treatments such as in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) are available to address this problem. However the rate of failure of these procedures remains relatively high.In the first part of this work the impact of maternal and paternal factors on the results of 194 IVF cycles and 586 ICSI cycles was studied. Results are mainly affected by maternal age, the number of oocytes retrieved and the number of mature oocytes collected. Neither paternal age nor spermatic parameters (number and mobility) are significantly associated with the failure of Assisted Reproductive Technologies (ART). Only the morphology of the sperm injected during ICSI influences fertilization rate.In the second part of this work apoptosis, DNA fragmentation and the chromosomal content before and after cell sorting with magnetic micro beads were studied in men with an abnormal level of sperm DNA fragmentation and in men with a constitutional chromosome abnormality. A significant decrease of apoptic spermatozoa with fragmented DNA and chromosome imbalance was observed. Thus cell sorting leading to the selection of better quality spermatozoa could become a reference method for ART.In a third part of the work a reliable protocol for the study of spermatic transcriptomes is designed.The development of these technologies will lead to a better understanding of the underlying causes ofART failure and thus increase the success rate.
32

Avaliação da função hormonal reprodutiva, parâmetros seminais e da fragmentação do DNA dos espermatozoides em pacientes com lúpus eritematoso sistêmico / Evaluation of sexual reproductive hormones, seminal parameters and sperm DNA fragmentation in patients with systemic lupus erythematosus

Tiseo, Bruno Camargo 25 June 2018 (has links)
Introdução: O lúpus eritematoso sistêmico (LES) é uma doença crônica autoimune com predomínio no sexo feminino e com evidente impacto em sua fertilidade. Por sua vez, em homens com LES foi observado alterações nos parâmetros seminais e nos níveis de hormônios sexuais. A análise seminal somente apresenta baixa correlação com potencial de fertilidade dos pacientes. Recentemente, a análise da integridade do DNA do espermatozoide tem mostrado melhor capacidade prognóstica para predizer a fertilidade do que os parâmetros seminais convencionais. Objetivo: Avaliar a fragmentação do DNA espermático de homens com LES sem azoospermia. Métodos: Vinte e oito pacientes homens, consecutivos, com LES (pelos critérios da ACR) e 34 controles foram avaliados conforme dados demográficos e de exposição ambiental, avaliação urológica, perfil hormonal e avaliação seminal (incluindo a fragmentação do DNA espermático). Aspectos clínicos, escores de atividade e dano cumulativo da doença e aspectos do tratamento também foram analisados. Resultados: Mediana da idade [33(20-52) vs. 36.5(25-54) anos, p=0.329] e frequência de varicocele (25% vs. 32%, p=0.183) foram similares entre o grupo de pacientes e o grupo controle. Na análise da fragmentação do DNA do espermatozoide observou-se quantidades significativamente mais altas de células classe III [44(9-88) vs. 16.5(0-80)%,p=0.001] e células classe IV [10.5(3-86) vs. 7(0-36)%,p=0.039] no grupo com LES. O índice de fragmentação do DNA espermático também foi significativamente mais alto em pacientes com LES [62(31-97) vs. 25.5(0-100)%, p < 0.001]. Parâmetros seminais convencionais (incluindo contagem espermática, motilidade e morfologia) foram similares em ambos os grupos. Dentro de grupo de pacientes com LES não foi observada correlação entre o índice de fragmentação do DNA espermático com idade, duração da doença, SLEDAI-2K e SLICC/ACR-DI ou dose cumulativa de predinisona, hidroxicloroquina, metotrexato, azatioprina, micofenolato mofetil ou ciclofosfamida intravenosa (CIC) (p > 0.05). Análises adicionais evidenciaram que motilidade espermática total foi significativamente menor no grupo que fez uso de CIC [64%(15-83) vs. 72%(57-86)%, p=0.024]. O índice de fragmentação do DNA espermático foi semelhante nos dois grupos [52.5(31-95) vs. 67.5(34-97)%, p=0.185]. Conclusões: Homens com SLE sem azoospermia apresentam maior índice de fragmentação do DNA espermático sem alteração dos parâmetros seminais ou hormonal. CIC não parece ter papel significativo nesta alteração. Estudos prospectivos futuros são necessários para determinar o impacto desta alteração na fertilidade destes pacientes / Introduction: Systemic lupus erythematosus (SLE) is a chronic autoimmune disease with a female predominance and have clear impact on fertility. In male SLE has been shown to alter seminal parameters and sexual hormonal levels. Recently, sperm DNA integrity analysis has shown better prognostic performance to predicting male fertility than seminal parameters. Objective: To evaluate sperm DNA fragmentation in non-azoospermic male SLE patients. Methods: Twenty-eight consecutive male SLE patients (ACR criteria) and 34 healthy controls were evaluated for demographic/exposures data, urologic evaluation, hormone profile and seminal analysis (including sperm DNA fragmentation). Clinical features, disease activity/damage scores and treatment were also assessed. Results: Median age [33(20-52) vs. 36.5(25-54) years, p=0.329] and frequency of varicocele (25% vs. 32%, p=0.183) were similar in SLE patients and healthy controls. Sperm DNA fragmentation showed significantly higher levels of cells class III [44(9-88) vs. 16.5(0-80)%, p=0.001] and cell class IV [10.5(3-86) vs. 7(0-36)%,p=0.039] in SLE. Sperm DNA fragmentation Index was also significantly higher in SLE patients [62(31-97) vs. 25.5(0-100)%, p < 0.001]. Conventional sperm parameters (including sperm count, motility and morphology) were similar in both groups. In SLE patients no correlations were observed between sperm DNA fragmentation index with age, disease duration, SLEDAI-2K and SLICC/ACR-DI scores, and cumulative dose of prednisone, hydroxychloroquine, intravenous cyclophosphamide (IVCYC), methotrexate, azathioprine and mycophenolate mofetil (p > 0.05). Further analysis of SLE patients treated with and without IVCYC showed that total sperm motility was significantly lower in the former group [64%(15-83) vs. 72%(57-86)%, p=0.024]. Sperm DNA fragmentation index was alike in both groups [52.5(31-95) vs. 67.5(34-97)%, p=0.185]. Conclusions: To our knowledge, this is the first demonstration that male non-azoospermic SLE patients have increased sperm DNA fragmentation without evident gonadal dysfunction. IVCYC does not seem to be a major determinant for this abnormality. Future prospective study is necessary to determine the impact of this alteration in these patients\' fertility
33

Impacto da obesidade e da cirurgia bariátrica na função erétil, hormônios reprodutivos, função testicular e fragmentação do DNA espermático / Impact of obesity and bariatric surgery on erectile function, reproductive hormones, testicular function, and sperm DNA fragmentation

Wood, Guilherme Jacom Abdulmassih 25 February 2019 (has links)
INTRODUÇÃO: A prevalência global da obesidade duplicou desde 1980, alcançando mais de 600 milhões de adultos obesos em 2014. Em paralelo a este aumento, alguns autores relataram uma tendência mundial de declínio da concentração de espermatozoides no ejaculado nas últimas décadas. Consequentemente, surge a hipótese da relação entre esses dois fatos temporais. Dentre todas as formas de tratamento da obesidade, a cirurgia bariátrica é a que apresenta melhores resultados em termos de perda de peso e melhor efetividade a longo-prazo. Há evidências na literatura que sugerem que a obesidade é capaz de alterar os níveis dos hormônios reprodutivos e função erétil. No entanto, seus efeitos sobre os parâmetros seminais clássicos e no índice de fragmentação do DNA espermático (IFD) são pouco estabelecidos. Além disso, o impacto da cirurgia bariátrica sobre estas alterações ainda não foi devidamente esclarecido. OBJETIVO: Identificar os efeitos da obesidade sobre a função erétil, hormônios reprodutivos, função testicular e IFD de homens obesos. Adicionalmente, avaliar se a cirurgia bariátrica é capaz de afetar estes mesmos parâmetros. MÉTODOS: Este estudo foi organizado em duas fases. Na primeira fase, indivíduos com índice de massa corpórea (IMC) menor que 30 kg/m2 e fertilidade comprovada foram comparados a pacientes obesos em programação para cirurgia bariátrica, com IMC maior que 35 kg/m2. Todos os pacientes foram submetidos a dosagem de hormônios reprodutivos, análise seminal e aferição do IFD pelo método do cometa alcalino. O questionário do Índice Internacional de Função Erétil (IIEF-5) foi aplicado. Na segunda fase, parte dos indivíduos obesos foi submetida à cirurgia bariátrica e todos foram convocados para reavaliação em 6 meses. RESULTADOS: Homens obesos apresentam maiores níveis séricos de estradiol, LH e FSH, e menores níveis séricos de testosterona total (TT) quando comparados com homens férteis eutróficos. Além disso, apresentam piores parâmetros seminais, com redução do volume ejaculado, concentração seminal, número total de espermatozoides no ejaculado, motilidade total, motilidade progressiva e percentual de espermatozoides com morfologia normal, e elevação do IFD. Na fase 2, homens obesos submetido a cirurgia bariátrica apresentaram elevação dos valores de FSH, SHBG, TT e testosterona livre (TL), e redução dos níveis de prolactina sérica. Além disso, apresentam queda da concentração seminal e do número total de espermatozoides no ejaculado, e queda na fragmentação do DNA espermático. Controles obesos, por outro lado, não apresentaram alterações nas variáveis estudadas. Além disso, maior intensidade da perda de peso esteve associada com alterações mais importantes do número total de espermatozoides no ejaculado, e dos níveis séricos de TT, TL, SHBG e FSH. CONCLUSÕES: A obesidade é capaz de induzir alterações importantes dos hormônios reprodutivos, parâmetros seminais e IFD. A cirurgia bariátrica, entretanto, pode reverter os efeitos deletérios sobre os hormônios reprodutivos e fragmentação do DNA, mas pode trazer piora de parâmetros seminais em 6 meses de seguimento / INTRODUCTION: Worldwide obesity prevalence has duplicated since 1980, reaching more than 600 million obese adults in 2014. Parallel to this increase, several authors have reported a global tendency of ejaculated sperm concentration decline in the last decades. Therefore, comes to light the hypothesis that these two temporal trends are related. Among all forms of obesity treatments, the one that reaches the best results and long-term effectiveness is the bariatric surgery. Growing evidence in the literature suggests that obesity is capable of altering reproductive hormones levels and erectile function. Effects on classic semen parameters and DNA fragmentation index (DFI), however, have not been properly established. OBJECTIVE: Determine the effects of obesity over erectile function, reproductive hormones, testicular function, and DFI in obese men. Additionally, evaluate if bariatric surgery can also impact those parameters. METHODS: This study was divided into two phases. On the first phase, individuals with body mass index (BMI) lower than 30 kg/m2 and proven fertility were compared to obese men, with BMI higher than 35 kg/m2, waiting to be submitted to bariatric surgery. Reproductive hormones evaluation, semen analysis and evaluation of DFI by the alkaline comet assay were performed in all patients. The International Index of Erectile Function (IIEF-5) was used to assess erectile function. On phase two, part of the obese patients was submitted to bariatric surgery, and all were invited to 6-month revaluation. RESULTS: Obese men have higher blood levels of estradiol, LH and FSH, and lower levels of total testosterone (TT) when compared to eutrophic fertile men. Additionally, they present worse semen parameters, with a reduction in ejaculated volume, sperm concentration, total number of sperm in the ejaculate, total motility, progressive motility, and percentage of normal sperm, and higher sperm DFI. On phase two, obese men submitted to bariatric surgery showed higher FSH, SHBG, TT, and free testosterone (FT) levels, and reduction of blood prolactin levels. Moreover, they exhibited a reduction in sperm concentration and total ejaculated sperm count, and a reduction in sperm DNA fragmentation. Obese controls, however, did not experience changes in the studied variables. Finally, the intensity of weight loss was associated with greater changes in total ejaculated sperm count and in TT, TL, SHBG and FSH blood levels. CONCLUSIONS: Obesity can induce important changes in reproductive hormones, semen parameters, and DFI. Bariatric surgery, however, can revert the deleterious effects in reproductive hormones and DFI, but can result in worsening of semen parameters on 6-month follow-up
34

Efeito da suplementação de melatonina e cafeína nas características estruturais e funcionais de espermatozoides pré-criopreservação e pós-descongelamento / Effect of melatonin and caffeine supplementation on the structural and functional characteristics of pre-cryopreservation and post-thaw spermatozoa

Pariz, Juliana Risso 18 August 2017 (has links)
A criopreservação de sêmen humano tem sido amplamente utilizada como método de preservação da fertilidade. A fim de reduzir os danos causados pelo processo de congelamento, diversos estudos utilizaram substâncias antioxidantes e estimulantes, porém, sua eficácia, bem como seu papel no controle funcional dos espermatozoides, não está bem estabelecida na literatura. Assim, o objetivo do estudo foi avaliar o efeito da suplementação de melatonina e cafeína nas características estruturais e funcionais de espermatozoides pré-criopreservação e pós-descongelamento. Para isso, este estudo prospectivo utilizou 30 amostras seminais de pacientes entre 19 e 45 anos de idade da rotina do Laboratório Androscience entre maio de 2013 e maio de 2017. Todas as amostras foram classificadas como normozoospérmicas, segundo análise seminal inicial de acordo com os critérios da Organização Mundial da Saúde (OMS). Em seguida, as amostras foram criopreservadas com Human Tubal Fluid modificado sem suplemento ou com 2mM de melatonina. Após o descongelamento, as amostras foram analisadas ou suplementadas com 2 mM de cafeína, incubadas por 15 minutos. Ao final dos experimentos, obtivemos 4 grupos: Amostras pós-descongelamento sem suplementação (CONT), amostras suplementadas com cafeína (CAF), melatonina (MEL) e cafeína + melatonina (CM). Parâmetros seminais de contagem, motilidade e cinética, analisados pelos critérios da OMS e pelo software SCA®, a atividade mitocondrial, pela coloração por diaminobenzidina, avaliação da taxa de fragmentação de DNA, pelo método SCSA® e a dosagem dos níveis de radicais livres de oxigênio (ROS), pelo método de luminescência, foram realizados pré-criopreservação e pós-descongelamento com ou sem suplementação. Os dados foram analisados pelo teste T de Student pareado e pela análise de variâncias de uma via com medidas repetidas, seguida pelo pós-teste de Holm-Sidak, e adotado um alfa de 5%. Observamos redução significativa concentração espermática (p < 0,001), motilidade total (p < 0,001) e progressiva (p < 0,001), parâmetros cinéticos (p < 0,009) e atividade mitocondrial (p < 0,001) e aumento das taxas de fragmentação de DNA (p=0,046) e ROS (p=0,052) nas amostras CONT quando comparadas com as amostras a fresco. Quando suplementadas com cafeína e melatonina, observamos aumento da motilidade progressiva nos grupos CAF (p=0,005) e CM (p=0,048) e aumento da atividade mitocondrial no grupo CM (p < 0,05). Podemos concluir que a associação da suplementação com cafeína e melatonina nas amostras pré-criopreservação e pós-descongelamento demonstrou ser uma ferramenta importante para ser aplicada em amostras criopreservadas para atuarem como substâncias estimuladoras de motilidade espermática / Human semen cryopreservation has been widely used as a method of preserving fertility. In order to reduce the damages caused by the freezing process, several studies used antioxidant and stimulant substances, however, their efficiency as well as their role in the functional control of spermatozoa have not been well established in literature. Thus, the goal of this study was to investigate the effect of melatonin and caffeine supplementation on the structural and functional characteristics of pre-cryopreservation and post-thaw spermatozoa. For this, this prospective study used 30 seminal samples from patients aged from 19 to 45 years in the routine of the Androscience Laboratory between May 2013 and May 2017. All samples were classified as normozoospermic, according to the initial seminal analysis following criteria of the World Health Organization (WHO). Then, the samples were cryopreserved with modified Human Tubal Fluid without supplement or with 2 mM of melatonin. After thawing, the samples were analyzed or supplemented with 2 mM of caffeine, and incubated for 15 minutes. At the end of the experiments, we obtained 4 groups: Post-thaw samples without supplementation (CONT), samples supplemented with caffeine (CAF), melatonin (MEL) and caffeine + melatonin (CM). Seminal parameters for count, motility and kinetics, analyzed by WHO criteria and by the SCA® software, mitochondrial activity, by diaminobenzidine staining, evaluation of DNA fragmentation rate, by the SCSA® method, and dosage of radical oxygen species (ROS) levels, by the luminescence method, pre-cryopreservation and post-thaw were carried out with or without supplementation. The data were analyzed by the paired Student\'s t-test and by one-way analysis of variance with repeated measurements, followed by the Holm-Sidak post-test, adopting an alpha of 5%. We observed a significant reduction in sperm concentration (p < 0.001), total (p < 0.001) and progressive (p < 0.001) motility, kinetic parameters (p < 0.009) and mitochondrial activity (p < 0.001), and increased rates of DNA fragmentation (p=0.046) and ROS (p=0.052) production in the CONT samples when compared with fresh sample. When supplemented with caffeine and melatonin, we observed an increase in progressive motility in the CAF (p=0.005) and CM (p=0.048) groups, and an increase in mitochondrial activity in CM group (p < 0.05). We can conclude that that the combination of caffeine and melatonin supplementation in pre-cryopreservation and post-thaw samples proved to be an important tool to be applied in cryopreserved samples to act as substances that stimulate sperm motility
35

Electric DNA chips for determination of pathogenic microorganisms

Liu, Yanling January 2008 (has links)
Silicon-based electric DNA chip arrays were utilized to fast identify pathogenic microorganisms with respect to the capacity to produce toxins involved in foodborne poisoning and infections. Bacteria of the B. cereus and the enterohemorrhagic E. coli (EHEC) groups contain different set-ups of various virulence factors that are encoded by the corresponding genes. The purpose of this work was to develop a fast and simple method for determination of the presence of these virulence genes in a colony from primary enrichment cultures. A target gene is detected through hybridization to a surface-immobilized specific capture probe and biotin-labeled detection probe. Following binding of an enzyme conjugate to this sandwich hybrid complex, a current signal is generated by electronic redox recycling of the enzymatic product paminophenol (pAP). Two versions of the assay were developed. In the first version the capture probes were immobilized on magnetic beads, which carried out all reactions until the pAP generation, while the final electric signal was created by transferring pAP to a single-electrode chip surface. In the second version a silicon chip array with 16 parallel sensing electrode positions each of them functionalized by capture probes, carried out all assay steps on the chip surface. This instrument can realize automatic and multiplexed gene detection. The kinetics of bacterial cell disruption and impact of DNA fragmentation by ultrasound were determined. The experimental data suggested that the increased signal after first minutes of ultrasonication were due to the accumulation of released DNA amount, while the further signal increase resulted from the improved hybridization with the shortened target DNA strands. Studies on probe localization on the 16-electrode chip assays indicated that the probe-targeting site, which was located at the 5’-end of strands, gave rise to the highest signal level due to the efficient targetprobes hybridization and the following enzyme binding. When these functionalized chip arrays were exposed to the cell homogenates, the sensing electrodes were fouled by cellular proteins and therefore led to dramatically decreased redox-recycling current. To circumvent this, samples were treated by DNA extraction after the 1st sonication and then DNA fragmentation by a 2nd time sonication. The DNA extract removed most of the interfering components from bacterial cell. This sample treatment was applied to characterize one “diarrheal” and one “emetic” strain of B. cereus with the chip arrays functionalized by eight DNA probes. The signal patterns of eight virulence genes from chip assays agreed well with PCR control analyses for both strains. By simply adding the SDS detergent to cell homogenates, chip surface blocking effect can be significantly reduced even without DNA extraction treatment. After optimization of some critical factors, the 16-electrode DNA chips with the improved sensing performance can directly detect multiple virulence genes from a single E. coli colony in 25 min after the introduction of supernatant of ultrasonicated cell lysate. / QC 20100824
36

Electric DNA arrays for determination of pathogenic Bacillus cereus

Liu, Yanling January 2007 (has links)
<p>Silicon-based electric chip arrays were developed for characterization of Bacillus</p><p>cereus with respect to the capacity to produce toxins involved in food poisoning and foodborne infections. Bacteria of the B. cereus group contain different sets of four toxins encoded by eight genes. The purpose of this work was to develop a fast method for determination of the presence of these genes in colonies from primary enrichment cultures. The specific DNA detection was based on immobilization of DNA capture probes, which hybridize to specific sites on the target genes. Biotin-labeled detection probes were designed to hybridize with the target DNA adjacent to the capture probes. An extravidin - alkaline phosphatase complex was subsequently bound to the hybridized detection probes. Finally, p-aminophenyl phosphate was added as substrate for the enzyme, and the product p-aminophenol was brought in contact with the interdigitated gold electrode on the silicon chips surface. The p-aminophenol was oxidized at the anode to quinoneimine, which was then reduced back to paminophenol at the cathode. This redox recycling generates a current that was used as the DNA-chip response to the target DNA. Two versions of the assay were used. In the first version the capture probes were immobilized on magnetic beads and all</p><p>chemical reactions until and including the enzymatic reaction took place in an</p><p>eppendorf tube while the redox recycling was used to measure the amount of paminophenol produced after transfer from the tube to the silicon chip surface. In the second version a silicon chip array was used with 16 parallel electrode positions, each activated by immobilization of one type of capture probes on the gold electrodes. With this system all chemical reactions took place at the chip surface. The kinetics of cell disruption and DNA fragmentation from B. cereus by ultrasonication was determined. Maximum cell disruption was achieved within 5 min and the chip response increased in proportion to the ultrasonic time. Further ultrasonication up to 10 min resulted in further increasing current although no further cell disruption was observed. If the sonication time was extended above 10 min the signal declined. Based on analysis of the DNA size distribution by early end-point PCR and gel electrophoresis, it is suggested that the first 5 min ultrasonication increased the signal by increasing the release of target DNA molecules. Thereafter the signal was increased by fragmentation of target DNA which increases the diffusion rate and also the accessibility of the hybridization site. Finally, the DNA fragment sizes approached that of the hybridization site (51-bp) which may reduce the signal because of cleavage of the target DNA in the hybridization region. These studies were performed with the bead-based hybridization assay. The assay was highly specific to the target gene (hblC) of both B. cereus and B. thuringiensis with no response from negative control</p><p>cells of B. subtilis. The 16 positions of the silicon chip array were activated by</p><p>immobilization of all known toxin-coding genes of B. cereus and also included both a positive control and a negative control electrode positions. When these chips were exposed to ultrasonicated B. cereus, the gold electrodes were fouled by some component in DNA cell lysates. To circumvent this, the released large DNA was first extracted and then ultrasonicated again, since the extract mainly contains large molecular weight DNA. This DNA extract was applied to characterize one “diarrheal” and one “emetic” strain of B. cereus with the DNA chip arrays. The results agreed with PCR control analysis which means that these electric DNA chip arrays can be used to characterize bacterial colonies with respect to the genes coding of all known toxins of B. cereus: haemolysin (hblA, hblC, hblD), non-haemolytic enterotoxin (nheA, nheB, nheC), cytotoxin K-2 (cytK-2), and cereulide (ces). The chip assay required about 30 min after application of DNA samples. Due to the generic properties of the chips, this technique should also be applicable for characterization of the pathogenicity potential of many other organisms. Keywords: Bacillus cereus, haemolysin, non-haemolytic enterotoxin, cytotoxin K-2, cereulide, toxin-coding genes, bacterial colony, electric DNA chip, ultrasonication, DNA fragmentation.</p>
37

Efeito da suplementação de melatonina e cafeína nas características estruturais e funcionais de espermatozoides pré-criopreservação e pós-descongelamento / Effect of melatonin and caffeine supplementation on the structural and functional characteristics of pre-cryopreservation and post-thaw spermatozoa

Juliana Risso Pariz 18 August 2017 (has links)
A criopreservação de sêmen humano tem sido amplamente utilizada como método de preservação da fertilidade. A fim de reduzir os danos causados pelo processo de congelamento, diversos estudos utilizaram substâncias antioxidantes e estimulantes, porém, sua eficácia, bem como seu papel no controle funcional dos espermatozoides, não está bem estabelecida na literatura. Assim, o objetivo do estudo foi avaliar o efeito da suplementação de melatonina e cafeína nas características estruturais e funcionais de espermatozoides pré-criopreservação e pós-descongelamento. Para isso, este estudo prospectivo utilizou 30 amostras seminais de pacientes entre 19 e 45 anos de idade da rotina do Laboratório Androscience entre maio de 2013 e maio de 2017. Todas as amostras foram classificadas como normozoospérmicas, segundo análise seminal inicial de acordo com os critérios da Organização Mundial da Saúde (OMS). Em seguida, as amostras foram criopreservadas com Human Tubal Fluid modificado sem suplemento ou com 2mM de melatonina. Após o descongelamento, as amostras foram analisadas ou suplementadas com 2 mM de cafeína, incubadas por 15 minutos. Ao final dos experimentos, obtivemos 4 grupos: Amostras pós-descongelamento sem suplementação (CONT), amostras suplementadas com cafeína (CAF), melatonina (MEL) e cafeína + melatonina (CM). Parâmetros seminais de contagem, motilidade e cinética, analisados pelos critérios da OMS e pelo software SCA®, a atividade mitocondrial, pela coloração por diaminobenzidina, avaliação da taxa de fragmentação de DNA, pelo método SCSA® e a dosagem dos níveis de radicais livres de oxigênio (ROS), pelo método de luminescência, foram realizados pré-criopreservação e pós-descongelamento com ou sem suplementação. Os dados foram analisados pelo teste T de Student pareado e pela análise de variâncias de uma via com medidas repetidas, seguida pelo pós-teste de Holm-Sidak, e adotado um alfa de 5%. Observamos redução significativa concentração espermática (p < 0,001), motilidade total (p < 0,001) e progressiva (p < 0,001), parâmetros cinéticos (p < 0,009) e atividade mitocondrial (p < 0,001) e aumento das taxas de fragmentação de DNA (p=0,046) e ROS (p=0,052) nas amostras CONT quando comparadas com as amostras a fresco. Quando suplementadas com cafeína e melatonina, observamos aumento da motilidade progressiva nos grupos CAF (p=0,005) e CM (p=0,048) e aumento da atividade mitocondrial no grupo CM (p < 0,05). Podemos concluir que a associação da suplementação com cafeína e melatonina nas amostras pré-criopreservação e pós-descongelamento demonstrou ser uma ferramenta importante para ser aplicada em amostras criopreservadas para atuarem como substâncias estimuladoras de motilidade espermática / Human semen cryopreservation has been widely used as a method of preserving fertility. In order to reduce the damages caused by the freezing process, several studies used antioxidant and stimulant substances, however, their efficiency as well as their role in the functional control of spermatozoa have not been well established in literature. Thus, the goal of this study was to investigate the effect of melatonin and caffeine supplementation on the structural and functional characteristics of pre-cryopreservation and post-thaw spermatozoa. For this, this prospective study used 30 seminal samples from patients aged from 19 to 45 years in the routine of the Androscience Laboratory between May 2013 and May 2017. All samples were classified as normozoospermic, according to the initial seminal analysis following criteria of the World Health Organization (WHO). Then, the samples were cryopreserved with modified Human Tubal Fluid without supplement or with 2 mM of melatonin. After thawing, the samples were analyzed or supplemented with 2 mM of caffeine, and incubated for 15 minutes. At the end of the experiments, we obtained 4 groups: Post-thaw samples without supplementation (CONT), samples supplemented with caffeine (CAF), melatonin (MEL) and caffeine + melatonin (CM). Seminal parameters for count, motility and kinetics, analyzed by WHO criteria and by the SCA® software, mitochondrial activity, by diaminobenzidine staining, evaluation of DNA fragmentation rate, by the SCSA® method, and dosage of radical oxygen species (ROS) levels, by the luminescence method, pre-cryopreservation and post-thaw were carried out with or without supplementation. The data were analyzed by the paired Student\'s t-test and by one-way analysis of variance with repeated measurements, followed by the Holm-Sidak post-test, adopting an alpha of 5%. We observed a significant reduction in sperm concentration (p < 0.001), total (p < 0.001) and progressive (p < 0.001) motility, kinetic parameters (p < 0.009) and mitochondrial activity (p < 0.001), and increased rates of DNA fragmentation (p=0.046) and ROS (p=0.052) production in the CONT samples when compared with fresh sample. When supplemented with caffeine and melatonin, we observed an increase in progressive motility in the CAF (p=0.005) and CM (p=0.048) groups, and an increase in mitochondrial activity in CM group (p < 0.05). We can conclude that that the combination of caffeine and melatonin supplementation in pre-cryopreservation and post-thaw samples proved to be an important tool to be applied in cryopreserved samples to act as substances that stimulate sperm motility
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Avaliação da função hormonal reprodutiva, parâmetros seminais e da fragmentação do DNA dos espermatozoides em pacientes com lúpus eritematoso sistêmico / Evaluation of sexual reproductive hormones, seminal parameters and sperm DNA fragmentation in patients with systemic lupus erythematosus

Bruno Camargo Tiseo 25 June 2018 (has links)
Introdução: O lúpus eritematoso sistêmico (LES) é uma doença crônica autoimune com predomínio no sexo feminino e com evidente impacto em sua fertilidade. Por sua vez, em homens com LES foi observado alterações nos parâmetros seminais e nos níveis de hormônios sexuais. A análise seminal somente apresenta baixa correlação com potencial de fertilidade dos pacientes. Recentemente, a análise da integridade do DNA do espermatozoide tem mostrado melhor capacidade prognóstica para predizer a fertilidade do que os parâmetros seminais convencionais. Objetivo: Avaliar a fragmentação do DNA espermático de homens com LES sem azoospermia. Métodos: Vinte e oito pacientes homens, consecutivos, com LES (pelos critérios da ACR) e 34 controles foram avaliados conforme dados demográficos e de exposição ambiental, avaliação urológica, perfil hormonal e avaliação seminal (incluindo a fragmentação do DNA espermático). Aspectos clínicos, escores de atividade e dano cumulativo da doença e aspectos do tratamento também foram analisados. Resultados: Mediana da idade [33(20-52) vs. 36.5(25-54) anos, p=0.329] e frequência de varicocele (25% vs. 32%, p=0.183) foram similares entre o grupo de pacientes e o grupo controle. Na análise da fragmentação do DNA do espermatozoide observou-se quantidades significativamente mais altas de células classe III [44(9-88) vs. 16.5(0-80)%,p=0.001] e células classe IV [10.5(3-86) vs. 7(0-36)%,p=0.039] no grupo com LES. O índice de fragmentação do DNA espermático também foi significativamente mais alto em pacientes com LES [62(31-97) vs. 25.5(0-100)%, p < 0.001]. Parâmetros seminais convencionais (incluindo contagem espermática, motilidade e morfologia) foram similares em ambos os grupos. Dentro de grupo de pacientes com LES não foi observada correlação entre o índice de fragmentação do DNA espermático com idade, duração da doença, SLEDAI-2K e SLICC/ACR-DI ou dose cumulativa de predinisona, hidroxicloroquina, metotrexato, azatioprina, micofenolato mofetil ou ciclofosfamida intravenosa (CIC) (p > 0.05). Análises adicionais evidenciaram que motilidade espermática total foi significativamente menor no grupo que fez uso de CIC [64%(15-83) vs. 72%(57-86)%, p=0.024]. O índice de fragmentação do DNA espermático foi semelhante nos dois grupos [52.5(31-95) vs. 67.5(34-97)%, p=0.185]. Conclusões: Homens com SLE sem azoospermia apresentam maior índice de fragmentação do DNA espermático sem alteração dos parâmetros seminais ou hormonal. CIC não parece ter papel significativo nesta alteração. Estudos prospectivos futuros são necessários para determinar o impacto desta alteração na fertilidade destes pacientes / Introduction: Systemic lupus erythematosus (SLE) is a chronic autoimmune disease with a female predominance and have clear impact on fertility. In male SLE has been shown to alter seminal parameters and sexual hormonal levels. Recently, sperm DNA integrity analysis has shown better prognostic performance to predicting male fertility than seminal parameters. Objective: To evaluate sperm DNA fragmentation in non-azoospermic male SLE patients. Methods: Twenty-eight consecutive male SLE patients (ACR criteria) and 34 healthy controls were evaluated for demographic/exposures data, urologic evaluation, hormone profile and seminal analysis (including sperm DNA fragmentation). Clinical features, disease activity/damage scores and treatment were also assessed. Results: Median age [33(20-52) vs. 36.5(25-54) years, p=0.329] and frequency of varicocele (25% vs. 32%, p=0.183) were similar in SLE patients and healthy controls. Sperm DNA fragmentation showed significantly higher levels of cells class III [44(9-88) vs. 16.5(0-80)%, p=0.001] and cell class IV [10.5(3-86) vs. 7(0-36)%,p=0.039] in SLE. Sperm DNA fragmentation Index was also significantly higher in SLE patients [62(31-97) vs. 25.5(0-100)%, p < 0.001]. Conventional sperm parameters (including sperm count, motility and morphology) were similar in both groups. In SLE patients no correlations were observed between sperm DNA fragmentation index with age, disease duration, SLEDAI-2K and SLICC/ACR-DI scores, and cumulative dose of prednisone, hydroxychloroquine, intravenous cyclophosphamide (IVCYC), methotrexate, azathioprine and mycophenolate mofetil (p > 0.05). Further analysis of SLE patients treated with and without IVCYC showed that total sperm motility was significantly lower in the former group [64%(15-83) vs. 72%(57-86)%, p=0.024]. Sperm DNA fragmentation index was alike in both groups [52.5(31-95) vs. 67.5(34-97)%, p=0.185]. Conclusions: To our knowledge, this is the first demonstration that male non-azoospermic SLE patients have increased sperm DNA fragmentation without evident gonadal dysfunction. IVCYC does not seem to be a major determinant for this abnormality. Future prospective study is necessary to determine the impact of this alteration in these patients\' fertility
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Noyau spermatique humatin et fertilité / Human sperm nucleus and fertility

Vorilhon, Solène 05 July 2019 (has links)
Chez l’Homme, les succès de la fécondation et d’un développement embryonnaire aboutissant à la naissance d’un enfant en bonne santé résident principalement dans la qualité des cellules reproductrices. Les dommages oxydants de l’ADN spermatique sont une cause majeure d’infertilité masculine. Afin de permettre une prise en charge thérapeutique optimale et adaptée, j’ai tout d’abord mis au point et validé un test diagnostique de l’oxydation de l’ADN spermatique par immunodétection du 8-hydroxy-2'-desoxyguanosine (8-OHdG), adduit majeur de l'oxydation nucléaire. Ce travail de thèse a déterminé, pour la première fois, un seuil d’oxydation de l’ADN spermatique en relation avec les paramètres conventionnels spermatiques. Dans un second temps, je me suis focalisée sur les atteintes de la chromatine et de l’ADN spermatique les plus fréquentes en cas d’infertilité masculine, à savoir les anomalies de condensation de la chromatine, la fragmentation et l’oxydation de l’ADN spermatique. Une corrélation entre l’oxydation de l’ADN, tout particulièrement la moyenne d’intensité de fluorescence, et le pourcentage de spermatozoïde fragmenté a été mise en évidence. Pour objectiver l’impact de ces dommages nucléaires spermatiques en pratique clinique, j’ai étudié, après cryopréservation, les effets bénéfiques d’une supplémentation en hypotaurine des milieux de sélection et de congélation/décongélation des échantillons. Une baisse de la cryocapacitation et du pourcentage de spermatozoïde fragmenté et décondensé ont été retrouvées ainsi qu’une amélioration de la vitalité et de la mobilité progressive spermatique. Enfin, comme le spermatozoïde a pour but ultime de participer à la genèse d’un nouvel individu, j’ai mis en évidence que la fragmentation et l’oxydation de l’ADN spermatique avaient un impact à des moments clés de la cinétique du développement embryonnaire précoce suite à une ICSI sans pour autant modifier l’obtention de blastocystes de bonne qualité. Ce travail de thèse a permis de mieux comprendre la physiopathologie de l’infertilité masculine et de mettre en évidence de nouveaux biomarqueurs spermatiques en lien avec un développement embryonnaire normal. / In humans, the success of fertilization and embryonic development leading to the birth of ahealthy child lies mainly in the quality of reproductive cells. Oxidative damage to sperm DNAis a major cause of male infertility. In order to provide optimal and appropriate therapeuticmanagement, I first developed and validated a diagnostic test for sperm DNA oxidation byimmunodetection of 8-hydroxy-2'-deoxyguanosine (8-OHdG), a major adduct of nuclearoxidation. This thesis work determined, for the first time, a threshold for the oxidation ofsperm DNA in relation to conventional sperm parameters. In a second step, I focused on themost common chromatin and sperm DNA disorders in male infertility, namely chromatincondensation anomalies, sperm DNA fragmentation and oxidation. A correlation betweenDNA oxidation, particularly the mean fluorescence intensity, and the percentage offragmented sperm was found. To objectify the impact of this nuclear sperm damage inclinical practice, I studied, after cryopreservation, the beneficial effects of hypotaurinesupplementation to the selection and freeze/thaw media of seed samples. A decrease incryocapacitation and the percentage of fragmented and decondensed sperm has beenfound, as well as an improvement in sperm vitality and progressive mobility. Finally, sincethe ultimate goal of the sperm cells is to participate in the genesis of a new individual, I haveshown that the fragmentation and oxidation of sperm DNA has an impact at key moments inthe kinetics of early embryonic development following ICSI without modifying the obtainingof good quality blastocysts. This thesis work has led to a better understanding of thepathophysiology of male infertility and the identification of new sperm biomarkers related tonormal embryonic development.
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Comparative evaluation of different extenders of bull semen stored under different conditions

Raseona, Andrea Motswetla 16 July 2015 (has links)
MSCAGR / Department of Animal Science / Preservation of semen is an important process to ensure that semen quality is sufficient for use in assisted reproductive technologies. This study evaluated the effectiveness of three different extenders to preserve bull semen stored under different conditions, as an alternative to frozen-thawed semen straws used for artificial insemination. Semen samples were collected from two Nguni bulls using an electro-ejaculator and transported to the laboratory at 37 °C for evaluation. Pooled semen was first aliquoted into three extenders namely Triladyl, Ham’s F10 and M199 at a dilution ratio of 1:4 (semen:extender), and then stored at controlled room temperature 24 °C. Secondly pooled semen was aliquoted into four groups of Ham’s F10 extender and diluted at a ratio of 1:4, then stored at 24 °C, 17 °C, 12 °C and 5 °C respectively. Sperm motility rates were analysed after 0, 24, 48 and 72 hours. Morphology, viability and sperm DNA fragmentation were analysed after 72 hours. The study was replicated four times and data was analysed by ANOVA. Triladyl had higher sperm viability rate and total motility rate for 72 hours (P<0.01). However, Ham’s F10 had higher progressive motility rate as compared to the other extenders. There was no significant difference (P<0.01), in the viability rate between Ham’s F10 and M199. No significant difference was also observed in total sperm abnormalities (absent tails, coiled tails and bent tails), except for reacted acrosomes (P>0.05), between the two Nguni bulls. Lower temperatures than 24 °C influenced sperm motility and viability in Ham’s F10. There was no significant difference in sperm DNA fragmentation rates (P<0.01), between all the four storage temperatures which indicated that temperature did not have an influence on sperm DNA fragmentation. In conclusion, bull semen can be preserved in Triladyl or Ham’s F10 and M199 culture media stored at 24 °C and stay alive for 72 hours. Triladyl proved to be the best suitable extender showing higher sperm viability and total motility rates as compared to Ham’s F10 and M199. Lower temperatures than 24 °C noticeably decreased sperm motility and viability in Ham’s F10 culture medium.

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